xref: /dflybsd-src/contrib/gcc-8.0/gcc/tree-cfg.c (revision fb3c2c0caaaa0e5d800e088b7dd7983e9ab009ec)
1 /* Control flow functions for trees.
2    Copyright (C) 2001-2018 Free Software Foundation, Inc.
3    Contributed by Diego Novillo <dnovillo@redhat.com>
4 
5 This file is part of GCC.
6 
7 GCC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 3, or (at your option)
10 any later version.
11 
12 GCC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15 GNU General Public License for more details.
16 
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3.  If not see
19 <http://www.gnu.org/licenses/>.  */
20 
21 #include "config.h"
22 #include "system.h"
23 #include "coretypes.h"
24 #include "backend.h"
25 #include "target.h"
26 #include "rtl.h"
27 #include "tree.h"
28 #include "gimple.h"
29 #include "cfghooks.h"
30 #include "tree-pass.h"
31 #include "ssa.h"
32 #include "cgraph.h"
33 #include "gimple-pretty-print.h"
34 #include "diagnostic-core.h"
35 #include "fold-const.h"
36 #include "trans-mem.h"
37 #include "stor-layout.h"
38 #include "print-tree.h"
39 #include "cfganal.h"
40 #include "gimple-fold.h"
41 #include "tree-eh.h"
42 #include "gimple-iterator.h"
43 #include "gimplify-me.h"
44 #include "gimple-walk.h"
45 #include "tree-cfg.h"
46 #include "tree-ssa-loop-manip.h"
47 #include "tree-ssa-loop-niter.h"
48 #include "tree-into-ssa.h"
49 #include "tree-dfa.h"
50 #include "tree-ssa.h"
51 #include "except.h"
52 #include "cfgloop.h"
53 #include "tree-ssa-propagate.h"
54 #include "value-prof.h"
55 #include "tree-inline.h"
56 #include "tree-ssa-live.h"
57 #include "omp-general.h"
58 #include "omp-expand.h"
59 #include "tree-cfgcleanup.h"
60 #include "gimplify.h"
61 #include "attribs.h"
62 #include "selftest.h"
63 #include "opts.h"
64 #include "asan.h"
65 
66 /* This file contains functions for building the Control Flow Graph (CFG)
67    for a function tree.  */
68 
69 /* Local declarations.  */
70 
71 /* Initial capacity for the basic block array.  */
72 static const int initial_cfg_capacity = 20;
73 
74 /* This hash table allows us to efficiently lookup all CASE_LABEL_EXPRs
75    which use a particular edge.  The CASE_LABEL_EXPRs are chained together
76    via their CASE_CHAIN field, which we clear after we're done with the
77    hash table to prevent problems with duplication of GIMPLE_SWITCHes.
78 
79    Access to this list of CASE_LABEL_EXPRs allows us to efficiently
80    update the case vector in response to edge redirections.
81 
82    Right now this table is set up and torn down at key points in the
83    compilation process.  It would be nice if we could make the table
84    more persistent.  The key is getting notification of changes to
85    the CFG (particularly edge removal, creation and redirection).  */
86 
87 static hash_map<edge, tree> *edge_to_cases;
88 
89 /* If we record edge_to_cases, this bitmap will hold indexes
90    of basic blocks that end in a GIMPLE_SWITCH which we touched
91    due to edge manipulations.  */
92 
93 static bitmap touched_switch_bbs;
94 
95 /* CFG statistics.  */
96 struct cfg_stats_d
97 {
98   long num_merged_labels;
99 };
100 
101 static struct cfg_stats_d cfg_stats;
102 
103 /* Data to pass to replace_block_vars_by_duplicates_1.  */
104 struct replace_decls_d
105 {
106   hash_map<tree, tree> *vars_map;
107   tree to_context;
108 };
109 
110 /* Hash table to store last discriminator assigned for each locus.  */
111 struct locus_discrim_map
112 {
113   location_t locus;
114   int discriminator;
115 };
116 
117 /* Hashtable helpers.  */
118 
119 struct locus_discrim_hasher : free_ptr_hash <locus_discrim_map>
120 {
121   static inline hashval_t hash (const locus_discrim_map *);
122   static inline bool equal (const locus_discrim_map *,
123 			    const locus_discrim_map *);
124 };
125 
126 /* Trivial hash function for a location_t.  ITEM is a pointer to
127    a hash table entry that maps a location_t to a discriminator.  */
128 
129 inline hashval_t
130 locus_discrim_hasher::hash (const locus_discrim_map *item)
131 {
132   return LOCATION_LINE (item->locus);
133 }
134 
135 /* Equality function for the locus-to-discriminator map.  A and B
136    point to the two hash table entries to compare.  */
137 
138 inline bool
139 locus_discrim_hasher::equal (const locus_discrim_map *a,
140 			     const locus_discrim_map *b)
141 {
142   return LOCATION_LINE (a->locus) == LOCATION_LINE (b->locus);
143 }
144 
145 static hash_table<locus_discrim_hasher> *discriminator_per_locus;
146 
147 /* Basic blocks and flowgraphs.  */
148 static void make_blocks (gimple_seq);
149 
150 /* Edges.  */
151 static void make_edges (void);
152 static void assign_discriminators (void);
153 static void make_cond_expr_edges (basic_block);
154 static void make_gimple_switch_edges (gswitch *, basic_block);
155 static bool make_goto_expr_edges (basic_block);
156 static void make_gimple_asm_edges (basic_block);
157 static edge gimple_redirect_edge_and_branch (edge, basic_block);
158 static edge gimple_try_redirect_by_replacing_jump (edge, basic_block);
159 
160 /* Various helpers.  */
161 static inline bool stmt_starts_bb_p (gimple *, gimple *);
162 static int gimple_verify_flow_info (void);
163 static void gimple_make_forwarder_block (edge);
164 static gimple *first_non_label_stmt (basic_block);
165 static bool verify_gimple_transaction (gtransaction *);
166 static bool call_can_make_abnormal_goto (gimple *);
167 
168 /* Flowgraph optimization and cleanup.  */
169 static void gimple_merge_blocks (basic_block, basic_block);
170 static bool gimple_can_merge_blocks_p (basic_block, basic_block);
171 static void remove_bb (basic_block);
172 static edge find_taken_edge_computed_goto (basic_block, tree);
173 static edge find_taken_edge_cond_expr (const gcond *, tree);
174 static edge find_taken_edge_switch_expr (const gswitch *, tree);
175 static tree find_case_label_for_value (const gswitch *, tree);
176 static void lower_phi_internal_fn ();
177 
178 void
179 init_empty_tree_cfg_for_function (struct function *fn)
180 {
181   /* Initialize the basic block array.  */
182   init_flow (fn);
183   profile_status_for_fn (fn) = PROFILE_ABSENT;
184   n_basic_blocks_for_fn (fn) = NUM_FIXED_BLOCKS;
185   last_basic_block_for_fn (fn) = NUM_FIXED_BLOCKS;
186   vec_alloc (basic_block_info_for_fn (fn), initial_cfg_capacity);
187   vec_safe_grow_cleared (basic_block_info_for_fn (fn),
188 			 initial_cfg_capacity);
189 
190   /* Build a mapping of labels to their associated blocks.  */
191   vec_alloc (label_to_block_map_for_fn (fn), initial_cfg_capacity);
192   vec_safe_grow_cleared (label_to_block_map_for_fn (fn),
193 			 initial_cfg_capacity);
194 
195   SET_BASIC_BLOCK_FOR_FN (fn, ENTRY_BLOCK, ENTRY_BLOCK_PTR_FOR_FN (fn));
196   SET_BASIC_BLOCK_FOR_FN (fn, EXIT_BLOCK, EXIT_BLOCK_PTR_FOR_FN (fn));
197 
198   ENTRY_BLOCK_PTR_FOR_FN (fn)->next_bb
199     = EXIT_BLOCK_PTR_FOR_FN (fn);
200   EXIT_BLOCK_PTR_FOR_FN (fn)->prev_bb
201     = ENTRY_BLOCK_PTR_FOR_FN (fn);
202 }
203 
204 void
205 init_empty_tree_cfg (void)
206 {
207   init_empty_tree_cfg_for_function (cfun);
208 }
209 
210 /*---------------------------------------------------------------------------
211 			      Create basic blocks
212 ---------------------------------------------------------------------------*/
213 
214 /* Entry point to the CFG builder for trees.  SEQ is the sequence of
215    statements to be added to the flowgraph.  */
216 
217 static void
218 build_gimple_cfg (gimple_seq seq)
219 {
220   /* Register specific gimple functions.  */
221   gimple_register_cfg_hooks ();
222 
223   memset ((void *) &cfg_stats, 0, sizeof (cfg_stats));
224 
225   init_empty_tree_cfg ();
226 
227   make_blocks (seq);
228 
229   /* Make sure there is always at least one block, even if it's empty.  */
230   if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS)
231     create_empty_bb (ENTRY_BLOCK_PTR_FOR_FN (cfun));
232 
233   /* Adjust the size of the array.  */
234   if (basic_block_info_for_fn (cfun)->length ()
235       < (size_t) n_basic_blocks_for_fn (cfun))
236     vec_safe_grow_cleared (basic_block_info_for_fn (cfun),
237 			   n_basic_blocks_for_fn (cfun));
238 
239   /* To speed up statement iterator walks, we first purge dead labels.  */
240   cleanup_dead_labels ();
241 
242   /* Group case nodes to reduce the number of edges.
243      We do this after cleaning up dead labels because otherwise we miss
244      a lot of obvious case merging opportunities.  */
245   group_case_labels ();
246 
247   /* Create the edges of the flowgraph.  */
248   discriminator_per_locus = new hash_table<locus_discrim_hasher> (13);
249   make_edges ();
250   assign_discriminators ();
251   lower_phi_internal_fn ();
252   cleanup_dead_labels ();
253   delete discriminator_per_locus;
254   discriminator_per_locus = NULL;
255 }
256 
257 /* Look for ANNOTATE calls with loop annotation kind in BB; if found, remove
258    them and propagate the information to LOOP.  We assume that the annotations
259    come immediately before the condition in BB, if any.  */
260 
261 static void
262 replace_loop_annotate_in_block (basic_block bb, struct loop *loop)
263 {
264   gimple_stmt_iterator gsi = gsi_last_bb (bb);
265   gimple *stmt = gsi_stmt (gsi);
266 
267   if (!(stmt && gimple_code (stmt) == GIMPLE_COND))
268     return;
269 
270   for (gsi_prev_nondebug (&gsi); !gsi_end_p (gsi); gsi_prev (&gsi))
271     {
272       stmt = gsi_stmt (gsi);
273       if (gimple_code (stmt) != GIMPLE_CALL)
274 	break;
275       if (!gimple_call_internal_p (stmt)
276 	  || gimple_call_internal_fn (stmt) != IFN_ANNOTATE)
277 	break;
278 
279       switch ((annot_expr_kind) tree_to_shwi (gimple_call_arg (stmt, 1)))
280 	{
281 	case annot_expr_ivdep_kind:
282 	  loop->safelen = INT_MAX;
283 	  break;
284 	case annot_expr_unroll_kind:
285 	  loop->unroll
286 	    = (unsigned short) tree_to_shwi (gimple_call_arg (stmt, 2));
287 	  cfun->has_unroll = true;
288 	  break;
289 	case annot_expr_no_vector_kind:
290 	  loop->dont_vectorize = true;
291 	  break;
292 	case annot_expr_vector_kind:
293 	  loop->force_vectorize = true;
294 	  cfun->has_force_vectorize_loops = true;
295 	  break;
296 	case annot_expr_parallel_kind:
297 	  loop->can_be_parallel = true;
298 	  loop->safelen = INT_MAX;
299 	  break;
300 	default:
301 	  gcc_unreachable ();
302 	}
303 
304       stmt = gimple_build_assign (gimple_call_lhs (stmt),
305 				  gimple_call_arg (stmt, 0));
306       gsi_replace (&gsi, stmt, true);
307     }
308 }
309 
310 /* Look for ANNOTATE calls with loop annotation kind; if found, remove
311    them and propagate the information to the loop.  We assume that the
312    annotations come immediately before the condition of the loop.  */
313 
314 static void
315 replace_loop_annotate (void)
316 {
317   struct loop *loop;
318   basic_block bb;
319   gimple_stmt_iterator gsi;
320   gimple *stmt;
321 
322   FOR_EACH_LOOP (loop, 0)
323     {
324       /* First look into the header.  */
325       replace_loop_annotate_in_block (loop->header, loop);
326 
327       /* Then look into the latch, if any.  */
328       if (loop->latch)
329 	replace_loop_annotate_in_block (loop->latch, loop);
330     }
331 
332   /* Remove IFN_ANNOTATE.  Safeguard for the case loop->latch == NULL.  */
333   FOR_EACH_BB_FN (bb, cfun)
334     {
335       for (gsi = gsi_last_bb (bb); !gsi_end_p (gsi); gsi_prev (&gsi))
336 	{
337 	  stmt = gsi_stmt (gsi);
338 	  if (gimple_code (stmt) != GIMPLE_CALL)
339 	    continue;
340 	  if (!gimple_call_internal_p (stmt)
341 	      || gimple_call_internal_fn (stmt) != IFN_ANNOTATE)
342 	    continue;
343 
344 	  switch ((annot_expr_kind) tree_to_shwi (gimple_call_arg (stmt, 1)))
345 	    {
346 	    case annot_expr_ivdep_kind:
347 	    case annot_expr_unroll_kind:
348 	    case annot_expr_no_vector_kind:
349 	    case annot_expr_vector_kind:
350 	    case annot_expr_parallel_kind:
351 	      break;
352 	    default:
353 	      gcc_unreachable ();
354 	    }
355 
356 	  warning_at (gimple_location (stmt), 0, "ignoring loop annotation");
357 	  stmt = gimple_build_assign (gimple_call_lhs (stmt),
358 				      gimple_call_arg (stmt, 0));
359 	  gsi_replace (&gsi, stmt, true);
360 	}
361     }
362 }
363 
364 /* Lower internal PHI function from GIMPLE FE.  */
365 
366 static void
367 lower_phi_internal_fn ()
368 {
369   basic_block bb, pred = NULL;
370   gimple_stmt_iterator gsi;
371   tree lhs;
372   gphi *phi_node;
373   gimple *stmt;
374 
375   /* After edge creation, handle __PHI function from GIMPLE FE.  */
376   FOR_EACH_BB_FN (bb, cfun)
377     {
378       for (gsi = gsi_after_labels (bb); !gsi_end_p (gsi);)
379 	{
380 	  stmt = gsi_stmt (gsi);
381 	  if (! gimple_call_internal_p (stmt, IFN_PHI))
382 	    break;
383 
384 	  lhs = gimple_call_lhs (stmt);
385 	  phi_node = create_phi_node (lhs, bb);
386 
387 	  /* Add arguments to the PHI node.  */
388 	  for (unsigned i = 0; i < gimple_call_num_args (stmt); ++i)
389 	    {
390 	      tree arg = gimple_call_arg (stmt, i);
391 	      if (TREE_CODE (arg) == LABEL_DECL)
392 		pred = label_to_block (arg);
393 	      else
394 		{
395 		  edge e = find_edge (pred, bb);
396 		  add_phi_arg (phi_node, arg, e, UNKNOWN_LOCATION);
397 		}
398 	    }
399 
400 	  gsi_remove (&gsi, true);
401 	}
402     }
403 }
404 
405 static unsigned int
406 execute_build_cfg (void)
407 {
408   gimple_seq body = gimple_body (current_function_decl);
409 
410   build_gimple_cfg (body);
411   gimple_set_body (current_function_decl, NULL);
412   if (dump_file && (dump_flags & TDF_DETAILS))
413     {
414       fprintf (dump_file, "Scope blocks:\n");
415       dump_scope_blocks (dump_file, dump_flags);
416     }
417   cleanup_tree_cfg ();
418   loop_optimizer_init (AVOID_CFG_MODIFICATIONS);
419   replace_loop_annotate ();
420   return 0;
421 }
422 
423 namespace {
424 
425 const pass_data pass_data_build_cfg =
426 {
427   GIMPLE_PASS, /* type */
428   "cfg", /* name */
429   OPTGROUP_NONE, /* optinfo_flags */
430   TV_TREE_CFG, /* tv_id */
431   PROP_gimple_leh, /* properties_required */
432   ( PROP_cfg | PROP_loops ), /* properties_provided */
433   0, /* properties_destroyed */
434   0, /* todo_flags_start */
435   0, /* todo_flags_finish */
436 };
437 
438 class pass_build_cfg : public gimple_opt_pass
439 {
440 public:
441   pass_build_cfg (gcc::context *ctxt)
442     : gimple_opt_pass (pass_data_build_cfg, ctxt)
443   {}
444 
445   /* opt_pass methods: */
446   virtual unsigned int execute (function *) { return execute_build_cfg (); }
447 
448 }; // class pass_build_cfg
449 
450 } // anon namespace
451 
452 gimple_opt_pass *
453 make_pass_build_cfg (gcc::context *ctxt)
454 {
455   return new pass_build_cfg (ctxt);
456 }
457 
458 
459 /* Return true if T is a computed goto.  */
460 
461 bool
462 computed_goto_p (gimple *t)
463 {
464   return (gimple_code (t) == GIMPLE_GOTO
465 	  && TREE_CODE (gimple_goto_dest (t)) != LABEL_DECL);
466 }
467 
468 /* Returns true if the sequence of statements STMTS only contains
469    a call to __builtin_unreachable ().  */
470 
471 bool
472 gimple_seq_unreachable_p (gimple_seq stmts)
473 {
474   if (stmts == NULL
475       /* Return false if -fsanitize=unreachable, we don't want to
476 	 optimize away those calls, but rather turn them into
477 	 __ubsan_handle_builtin_unreachable () or __builtin_trap ()
478 	 later.  */
479       || sanitize_flags_p (SANITIZE_UNREACHABLE))
480     return false;
481 
482   gimple_stmt_iterator gsi = gsi_last (stmts);
483 
484   if (!gimple_call_builtin_p (gsi_stmt (gsi), BUILT_IN_UNREACHABLE))
485     return false;
486 
487   for (gsi_prev (&gsi); !gsi_end_p (gsi); gsi_prev (&gsi))
488     {
489       gimple *stmt = gsi_stmt (gsi);
490       if (gimple_code (stmt) != GIMPLE_LABEL
491 	  && !is_gimple_debug (stmt)
492 	  && !gimple_clobber_p (stmt))
493       return false;
494     }
495   return true;
496 }
497 
498 /* Returns true for edge E where e->src ends with a GIMPLE_COND and
499    the other edge points to a bb with just __builtin_unreachable ().
500    I.e. return true for C->M edge in:
501    <bb C>:
502    ...
503    if (something)
504      goto <bb N>;
505    else
506      goto <bb M>;
507    <bb N>:
508    __builtin_unreachable ();
509    <bb M>:  */
510 
511 bool
512 assert_unreachable_fallthru_edge_p (edge e)
513 {
514   basic_block pred_bb = e->src;
515   gimple *last = last_stmt (pred_bb);
516   if (last && gimple_code (last) == GIMPLE_COND)
517     {
518       basic_block other_bb = EDGE_SUCC (pred_bb, 0)->dest;
519       if (other_bb == e->dest)
520 	other_bb = EDGE_SUCC (pred_bb, 1)->dest;
521       if (EDGE_COUNT (other_bb->succs) == 0)
522 	return gimple_seq_unreachable_p (bb_seq (other_bb));
523     }
524   return false;
525 }
526 
527 
528 /* Initialize GF_CALL_CTRL_ALTERING flag, which indicates the call
529    could alter control flow except via eh. We initialize the flag at
530    CFG build time and only ever clear it later.  */
531 
532 static void
533 gimple_call_initialize_ctrl_altering (gimple *stmt)
534 {
535   int flags = gimple_call_flags (stmt);
536 
537   /* A call alters control flow if it can make an abnormal goto.  */
538   if (call_can_make_abnormal_goto (stmt)
539       /* A call also alters control flow if it does not return.  */
540       || flags & ECF_NORETURN
541       /* TM ending statements have backedges out of the transaction.
542 	 Return true so we split the basic block containing them.
543 	 Note that the TM_BUILTIN test is merely an optimization.  */
544       || ((flags & ECF_TM_BUILTIN)
545 	  && is_tm_ending_fndecl (gimple_call_fndecl (stmt)))
546       /* BUILT_IN_RETURN call is same as return statement.  */
547       || gimple_call_builtin_p (stmt, BUILT_IN_RETURN)
548       /* IFN_UNIQUE should be the last insn, to make checking for it
549 	 as cheap as possible.  */
550       || (gimple_call_internal_p (stmt)
551 	  && gimple_call_internal_unique_p (stmt)))
552     gimple_call_set_ctrl_altering (stmt, true);
553   else
554     gimple_call_set_ctrl_altering (stmt, false);
555 }
556 
557 
558 /* Insert SEQ after BB and build a flowgraph.  */
559 
560 static basic_block
561 make_blocks_1 (gimple_seq seq, basic_block bb)
562 {
563   gimple_stmt_iterator i = gsi_start (seq);
564   gimple *stmt = NULL;
565   gimple *prev_stmt = NULL;
566   bool start_new_block = true;
567   bool first_stmt_of_seq = true;
568 
569   while (!gsi_end_p (i))
570     {
571       /* PREV_STMT should only be set to a debug stmt if the debug
572 	 stmt is before nondebug stmts.  Once stmt reaches a nondebug
573 	 nonlabel, prev_stmt will be set to it, so that
574 	 stmt_starts_bb_p will know to start a new block if a label is
575 	 found.  However, if stmt was a label after debug stmts only,
576 	 keep the label in prev_stmt even if we find further debug
577 	 stmts, for there may be other labels after them, and they
578 	 should land in the same block.  */
579       if (!prev_stmt || !stmt || !is_gimple_debug (stmt))
580 	prev_stmt = stmt;
581       stmt = gsi_stmt (i);
582 
583       if (stmt && is_gimple_call (stmt))
584 	gimple_call_initialize_ctrl_altering (stmt);
585 
586       /* If the statement starts a new basic block or if we have determined
587 	 in a previous pass that we need to create a new block for STMT, do
588 	 so now.  */
589       if (start_new_block || stmt_starts_bb_p (stmt, prev_stmt))
590 	{
591 	  if (!first_stmt_of_seq)
592 	    gsi_split_seq_before (&i, &seq);
593 	  bb = create_basic_block (seq, bb);
594 	  start_new_block = false;
595 	  prev_stmt = NULL;
596 	}
597 
598       /* Now add STMT to BB and create the subgraphs for special statement
599 	 codes.  */
600       gimple_set_bb (stmt, bb);
601 
602       /* If STMT is a basic block terminator, set START_NEW_BLOCK for the
603 	 next iteration.  */
604       if (stmt_ends_bb_p (stmt))
605 	{
606 	  /* If the stmt can make abnormal goto use a new temporary
607 	     for the assignment to the LHS.  This makes sure the old value
608 	     of the LHS is available on the abnormal edge.  Otherwise
609 	     we will end up with overlapping life-ranges for abnormal
610 	     SSA names.  */
611 	  if (gimple_has_lhs (stmt)
612 	      && stmt_can_make_abnormal_goto (stmt)
613 	      && is_gimple_reg_type (TREE_TYPE (gimple_get_lhs (stmt))))
614 	    {
615 	      tree lhs = gimple_get_lhs (stmt);
616 	      tree tmp = create_tmp_var (TREE_TYPE (lhs));
617 	      gimple *s = gimple_build_assign (lhs, tmp);
618 	      gimple_set_location (s, gimple_location (stmt));
619 	      gimple_set_block (s, gimple_block (stmt));
620 	      gimple_set_lhs (stmt, tmp);
621 	      if (TREE_CODE (TREE_TYPE (tmp)) == COMPLEX_TYPE
622 		  || TREE_CODE (TREE_TYPE (tmp)) == VECTOR_TYPE)
623 		DECL_GIMPLE_REG_P (tmp) = 1;
624 	      gsi_insert_after (&i, s, GSI_SAME_STMT);
625 	    }
626 	  start_new_block = true;
627 	}
628 
629       gsi_next (&i);
630       first_stmt_of_seq = false;
631     }
632   return bb;
633 }
634 
635 /* Build a flowgraph for the sequence of stmts SEQ.  */
636 
637 static void
638 make_blocks (gimple_seq seq)
639 {
640   /* Look for debug markers right before labels, and move the debug
641      stmts after the labels.  Accepting labels among debug markers
642      adds no value, just complexity; if we wanted to annotate labels
643      with view numbers (so sequencing among markers would matter) or
644      somesuch, we're probably better off still moving the labels, but
645      adding other debug annotations in their original positions or
646      emitting nonbind or bind markers associated with the labels in
647      the original position of the labels.
648 
649      Moving labels would probably be simpler, but we can't do that:
650      moving labels assigns label ids to them, and doing so because of
651      debug markers makes for -fcompare-debug and possibly even codegen
652      differences.  So, we have to move the debug stmts instead.  To
653      that end, we scan SEQ backwards, marking the position of the
654      latest (earliest we find) label, and moving debug stmts that are
655      not separated from it by nondebug nonlabel stmts after the
656      label.  */
657   if (MAY_HAVE_DEBUG_MARKER_STMTS)
658     {
659       gimple_stmt_iterator label = gsi_none ();
660 
661       for (gimple_stmt_iterator i = gsi_last (seq); !gsi_end_p (i); gsi_prev (&i))
662 	{
663 	  gimple *stmt = gsi_stmt (i);
664 
665 	  /* If this is the first label we encounter (latest in SEQ)
666 	     before nondebug stmts, record its position.  */
667 	  if (is_a <glabel *> (stmt))
668 	    {
669 	      if (gsi_end_p (label))
670 		label = i;
671 	      continue;
672 	    }
673 
674 	  /* Without a recorded label position to move debug stmts to,
675 	     there's nothing to do.  */
676 	  if (gsi_end_p (label))
677 	    continue;
678 
679 	  /* Move the debug stmt at I after LABEL.  */
680 	  if (is_gimple_debug (stmt))
681 	    {
682 	      gcc_assert (gimple_debug_nonbind_marker_p (stmt));
683 	      /* As STMT is removed, I advances to the stmt after
684 		 STMT, so the gsi_prev in the for "increment"
685 		 expression gets us to the stmt we're to visit after
686 		 STMT.  LABEL, however, would advance to the moved
687 		 stmt if we passed it to gsi_move_after, so pass it a
688 		 copy instead, so as to keep LABEL pointing to the
689 		 LABEL.  */
690 	      gimple_stmt_iterator copy = label;
691 	      gsi_move_after (&i, &copy);
692 	      continue;
693 	    }
694 
695 	  /* There aren't any (more?) debug stmts before label, so
696 	     there isn't anything else to move after it.  */
697 	  label = gsi_none ();
698 	}
699     }
700 
701   make_blocks_1 (seq, ENTRY_BLOCK_PTR_FOR_FN (cfun));
702 }
703 
704 /* Create and return a new empty basic block after bb AFTER.  */
705 
706 static basic_block
707 create_bb (void *h, void *e, basic_block after)
708 {
709   basic_block bb;
710 
711   gcc_assert (!e);
712 
713   /* Create and initialize a new basic block.  Since alloc_block uses
714      GC allocation that clears memory to allocate a basic block, we do
715      not have to clear the newly allocated basic block here.  */
716   bb = alloc_block ();
717 
718   bb->index = last_basic_block_for_fn (cfun);
719   bb->flags = BB_NEW;
720   set_bb_seq (bb, h ? (gimple_seq) h : NULL);
721 
722   /* Add the new block to the linked list of blocks.  */
723   link_block (bb, after);
724 
725   /* Grow the basic block array if needed.  */
726   if ((size_t) last_basic_block_for_fn (cfun)
727       == basic_block_info_for_fn (cfun)->length ())
728     {
729       size_t new_size =
730 	(last_basic_block_for_fn (cfun)
731 	 + (last_basic_block_for_fn (cfun) + 3) / 4);
732       vec_safe_grow_cleared (basic_block_info_for_fn (cfun), new_size);
733     }
734 
735   /* Add the newly created block to the array.  */
736   SET_BASIC_BLOCK_FOR_FN (cfun, last_basic_block_for_fn (cfun), bb);
737 
738   n_basic_blocks_for_fn (cfun)++;
739   last_basic_block_for_fn (cfun)++;
740 
741   return bb;
742 }
743 
744 
745 /*---------------------------------------------------------------------------
746 				 Edge creation
747 ---------------------------------------------------------------------------*/
748 
749 /* If basic block BB has an abnormal edge to a basic block
750    containing IFN_ABNORMAL_DISPATCHER internal call, return
751    that the dispatcher's basic block, otherwise return NULL.  */
752 
753 basic_block
754 get_abnormal_succ_dispatcher (basic_block bb)
755 {
756   edge e;
757   edge_iterator ei;
758 
759   FOR_EACH_EDGE (e, ei, bb->succs)
760     if ((e->flags & (EDGE_ABNORMAL | EDGE_EH)) == EDGE_ABNORMAL)
761       {
762 	gimple_stmt_iterator gsi
763 	  = gsi_start_nondebug_after_labels_bb (e->dest);
764 	gimple *g = gsi_stmt (gsi);
765 	if (g && gimple_call_internal_p (g, IFN_ABNORMAL_DISPATCHER))
766 	  return e->dest;
767       }
768   return NULL;
769 }
770 
771 /* Helper function for make_edges.  Create a basic block with
772    with ABNORMAL_DISPATCHER internal call in it if needed, and
773    create abnormal edges from BBS to it and from it to FOR_BB
774    if COMPUTED_GOTO is false, otherwise factor the computed gotos.  */
775 
776 static void
777 handle_abnormal_edges (basic_block *dispatcher_bbs,
778 		       basic_block for_bb, int *bb_to_omp_idx,
779 		       auto_vec<basic_block> *bbs, bool computed_goto)
780 {
781   basic_block *dispatcher = dispatcher_bbs + (computed_goto ? 1 : 0);
782   unsigned int idx = 0;
783   basic_block bb;
784   bool inner = false;
785 
786   if (bb_to_omp_idx)
787     {
788       dispatcher = dispatcher_bbs + 2 * bb_to_omp_idx[for_bb->index];
789       if (bb_to_omp_idx[for_bb->index] != 0)
790 	inner = true;
791     }
792 
793   /* If the dispatcher has been created already, then there are basic
794      blocks with abnormal edges to it, so just make a new edge to
795      for_bb.  */
796   if (*dispatcher == NULL)
797     {
798       /* Check if there are any basic blocks that need to have
799 	 abnormal edges to this dispatcher.  If there are none, return
800 	 early.  */
801       if (bb_to_omp_idx == NULL)
802 	{
803 	  if (bbs->is_empty ())
804 	    return;
805 	}
806       else
807 	{
808 	  FOR_EACH_VEC_ELT (*bbs, idx, bb)
809 	    if (bb_to_omp_idx[bb->index] == bb_to_omp_idx[for_bb->index])
810 	      break;
811 	  if (bb == NULL)
812 	    return;
813 	}
814 
815       /* Create the dispatcher bb.  */
816       *dispatcher = create_basic_block (NULL, for_bb);
817       if (computed_goto)
818 	{
819 	  /* Factor computed gotos into a common computed goto site.  Also
820 	     record the location of that site so that we can un-factor the
821 	     gotos after we have converted back to normal form.  */
822 	  gimple_stmt_iterator gsi = gsi_start_bb (*dispatcher);
823 
824 	  /* Create the destination of the factored goto.  Each original
825 	     computed goto will put its desired destination into this
826 	     variable and jump to the label we create immediately below.  */
827 	  tree var = create_tmp_var (ptr_type_node, "gotovar");
828 
829 	  /* Build a label for the new block which will contain the
830 	     factored computed goto.  */
831 	  tree factored_label_decl
832 	    = create_artificial_label (UNKNOWN_LOCATION);
833 	  gimple *factored_computed_goto_label
834 	    = gimple_build_label (factored_label_decl);
835 	  gsi_insert_after (&gsi, factored_computed_goto_label, GSI_NEW_STMT);
836 
837 	  /* Build our new computed goto.  */
838 	  gimple *factored_computed_goto = gimple_build_goto (var);
839 	  gsi_insert_after (&gsi, factored_computed_goto, GSI_NEW_STMT);
840 
841 	  FOR_EACH_VEC_ELT (*bbs, idx, bb)
842 	    {
843 	      if (bb_to_omp_idx
844 		  && bb_to_omp_idx[bb->index] != bb_to_omp_idx[for_bb->index])
845 		continue;
846 
847 	      gsi = gsi_last_bb (bb);
848 	      gimple *last = gsi_stmt (gsi);
849 
850 	      gcc_assert (computed_goto_p (last));
851 
852 	      /* Copy the original computed goto's destination into VAR.  */
853 	      gimple *assignment
854 		= gimple_build_assign (var, gimple_goto_dest (last));
855 	      gsi_insert_before (&gsi, assignment, GSI_SAME_STMT);
856 
857 	      edge e = make_edge (bb, *dispatcher, EDGE_FALLTHRU);
858 	      e->goto_locus = gimple_location (last);
859 	      gsi_remove (&gsi, true);
860 	    }
861 	}
862       else
863 	{
864 	  tree arg = inner ? boolean_true_node : boolean_false_node;
865 	  gimple *g = gimple_build_call_internal (IFN_ABNORMAL_DISPATCHER,
866 						 1, arg);
867 	  gimple_stmt_iterator gsi = gsi_after_labels (*dispatcher);
868 	  gsi_insert_after (&gsi, g, GSI_NEW_STMT);
869 
870 	  /* Create predecessor edges of the dispatcher.  */
871 	  FOR_EACH_VEC_ELT (*bbs, idx, bb)
872 	    {
873 	      if (bb_to_omp_idx
874 		  && bb_to_omp_idx[bb->index] != bb_to_omp_idx[for_bb->index])
875 		continue;
876 	      make_edge (bb, *dispatcher, EDGE_ABNORMAL);
877 	    }
878 	}
879     }
880 
881   make_edge (*dispatcher, for_bb, EDGE_ABNORMAL);
882 }
883 
884 /* Creates outgoing edges for BB.  Returns 1 when it ends with an
885    computed goto, returns 2 when it ends with a statement that
886    might return to this function via an nonlocal goto, otherwise
887    return 0.  Updates *PCUR_REGION with the OMP region this BB is in.  */
888 
889 static int
890 make_edges_bb (basic_block bb, struct omp_region **pcur_region, int *pomp_index)
891 {
892   gimple *last = last_stmt (bb);
893   bool fallthru = false;
894   int ret = 0;
895 
896   if (!last)
897     return ret;
898 
899   switch (gimple_code (last))
900     {
901     case GIMPLE_GOTO:
902       if (make_goto_expr_edges (bb))
903 	ret = 1;
904       fallthru = false;
905       break;
906     case GIMPLE_RETURN:
907       {
908 	edge e = make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), 0);
909 	e->goto_locus = gimple_location (last);
910 	fallthru = false;
911       }
912       break;
913     case GIMPLE_COND:
914       make_cond_expr_edges (bb);
915       fallthru = false;
916       break;
917     case GIMPLE_SWITCH:
918       make_gimple_switch_edges (as_a <gswitch *> (last), bb);
919       fallthru = false;
920       break;
921     case GIMPLE_RESX:
922       make_eh_edges (last);
923       fallthru = false;
924       break;
925     case GIMPLE_EH_DISPATCH:
926       fallthru = make_eh_dispatch_edges (as_a <geh_dispatch *> (last));
927       break;
928 
929     case GIMPLE_CALL:
930       /* If this function receives a nonlocal goto, then we need to
931 	 make edges from this call site to all the nonlocal goto
932 	 handlers.  */
933       if (stmt_can_make_abnormal_goto (last))
934 	ret = 2;
935 
936       /* If this statement has reachable exception handlers, then
937 	 create abnormal edges to them.  */
938       make_eh_edges (last);
939 
940       /* BUILTIN_RETURN is really a return statement.  */
941       if (gimple_call_builtin_p (last, BUILT_IN_RETURN))
942 	{
943 	  make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), 0);
944 	  fallthru = false;
945 	}
946       /* Some calls are known not to return.  */
947       else
948 	fallthru = !gimple_call_noreturn_p (last);
949       break;
950 
951     case GIMPLE_ASSIGN:
952       /* A GIMPLE_ASSIGN may throw internally and thus be considered
953 	 control-altering.  */
954       if (is_ctrl_altering_stmt (last))
955 	make_eh_edges (last);
956       fallthru = true;
957       break;
958 
959     case GIMPLE_ASM:
960       make_gimple_asm_edges (bb);
961       fallthru = true;
962       break;
963 
964     CASE_GIMPLE_OMP:
965       fallthru = omp_make_gimple_edges (bb, pcur_region, pomp_index);
966       break;
967 
968     case GIMPLE_TRANSACTION:
969       {
970         gtransaction *txn = as_a <gtransaction *> (last);
971 	tree label1 = gimple_transaction_label_norm (txn);
972 	tree label2 = gimple_transaction_label_uninst (txn);
973 
974 	if (label1)
975 	  make_edge (bb, label_to_block (label1), EDGE_FALLTHRU);
976 	if (label2)
977 	  make_edge (bb, label_to_block (label2),
978 		     EDGE_TM_UNINSTRUMENTED | (label1 ? 0 : EDGE_FALLTHRU));
979 
980 	tree label3 = gimple_transaction_label_over (txn);
981 	if (gimple_transaction_subcode (txn)
982 	    & (GTMA_HAVE_ABORT | GTMA_IS_OUTER))
983 	  make_edge (bb, label_to_block (label3), EDGE_TM_ABORT);
984 
985 	fallthru = false;
986       }
987       break;
988 
989     default:
990       gcc_assert (!stmt_ends_bb_p (last));
991       fallthru = true;
992       break;
993     }
994 
995   if (fallthru)
996     make_edge (bb, bb->next_bb, EDGE_FALLTHRU);
997 
998   return ret;
999 }
1000 
1001 /* Join all the blocks in the flowgraph.  */
1002 
1003 static void
1004 make_edges (void)
1005 {
1006   basic_block bb;
1007   struct omp_region *cur_region = NULL;
1008   auto_vec<basic_block> ab_edge_goto;
1009   auto_vec<basic_block> ab_edge_call;
1010   int *bb_to_omp_idx = NULL;
1011   int cur_omp_region_idx = 0;
1012 
1013   /* Create an edge from entry to the first block with executable
1014      statements in it.  */
1015   make_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun),
1016 	     BASIC_BLOCK_FOR_FN (cfun, NUM_FIXED_BLOCKS),
1017 	     EDGE_FALLTHRU);
1018 
1019   /* Traverse the basic block array placing edges.  */
1020   FOR_EACH_BB_FN (bb, cfun)
1021     {
1022       int mer;
1023 
1024       if (bb_to_omp_idx)
1025 	bb_to_omp_idx[bb->index] = cur_omp_region_idx;
1026 
1027       mer = make_edges_bb (bb, &cur_region, &cur_omp_region_idx);
1028       if (mer == 1)
1029 	ab_edge_goto.safe_push (bb);
1030       else if (mer == 2)
1031 	ab_edge_call.safe_push (bb);
1032 
1033       if (cur_region && bb_to_omp_idx == NULL)
1034 	bb_to_omp_idx = XCNEWVEC (int, n_basic_blocks_for_fn (cfun));
1035     }
1036 
1037   /* Computed gotos are hell to deal with, especially if there are
1038      lots of them with a large number of destinations.  So we factor
1039      them to a common computed goto location before we build the
1040      edge list.  After we convert back to normal form, we will un-factor
1041      the computed gotos since factoring introduces an unwanted jump.
1042      For non-local gotos and abnormal edges from calls to calls that return
1043      twice or forced labels, factor the abnormal edges too, by having all
1044      abnormal edges from the calls go to a common artificial basic block
1045      with ABNORMAL_DISPATCHER internal call and abnormal edges from that
1046      basic block to all forced labels and calls returning twice.
1047      We do this per-OpenMP structured block, because those regions
1048      are guaranteed to be single entry single exit by the standard,
1049      so it is not allowed to enter or exit such regions abnormally this way,
1050      thus all computed gotos, non-local gotos and setjmp/longjmp calls
1051      must not transfer control across SESE region boundaries.  */
1052   if (!ab_edge_goto.is_empty () || !ab_edge_call.is_empty ())
1053     {
1054       gimple_stmt_iterator gsi;
1055       basic_block dispatcher_bb_array[2] = { NULL, NULL };
1056       basic_block *dispatcher_bbs = dispatcher_bb_array;
1057       int count = n_basic_blocks_for_fn (cfun);
1058 
1059       if (bb_to_omp_idx)
1060 	dispatcher_bbs = XCNEWVEC (basic_block, 2 * count);
1061 
1062       FOR_EACH_BB_FN (bb, cfun)
1063 	{
1064 	  for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
1065 	    {
1066 	      glabel *label_stmt = dyn_cast <glabel *> (gsi_stmt (gsi));
1067 	      tree target;
1068 
1069 	      if (!label_stmt)
1070 		break;
1071 
1072 	      target = gimple_label_label (label_stmt);
1073 
1074 	      /* Make an edge to every label block that has been marked as a
1075 		 potential target for a computed goto or a non-local goto.  */
1076 	      if (FORCED_LABEL (target))
1077 		handle_abnormal_edges (dispatcher_bbs, bb, bb_to_omp_idx,
1078 				       &ab_edge_goto, true);
1079 	      if (DECL_NONLOCAL (target))
1080 		{
1081 		  handle_abnormal_edges (dispatcher_bbs, bb, bb_to_omp_idx,
1082 					 &ab_edge_call, false);
1083 		  break;
1084 		}
1085 	    }
1086 
1087 	  if (!gsi_end_p (gsi) && is_gimple_debug (gsi_stmt (gsi)))
1088 	    gsi_next_nondebug (&gsi);
1089 	  if (!gsi_end_p (gsi))
1090 	    {
1091 	      /* Make an edge to every setjmp-like call.  */
1092 	      gimple *call_stmt = gsi_stmt (gsi);
1093 	      if (is_gimple_call (call_stmt)
1094 		  && ((gimple_call_flags (call_stmt) & ECF_RETURNS_TWICE)
1095 		      || gimple_call_builtin_p (call_stmt,
1096 						BUILT_IN_SETJMP_RECEIVER)))
1097 		handle_abnormal_edges (dispatcher_bbs, bb, bb_to_omp_idx,
1098 				       &ab_edge_call, false);
1099 	    }
1100 	}
1101 
1102       if (bb_to_omp_idx)
1103 	XDELETE (dispatcher_bbs);
1104     }
1105 
1106   XDELETE (bb_to_omp_idx);
1107 
1108   omp_free_regions ();
1109 }
1110 
1111 /* Add SEQ after GSI.  Start new bb after GSI, and created further bbs as
1112    needed.  Returns true if new bbs were created.
1113    Note: This is transitional code, and should not be used for new code.  We
1114    should be able to get rid of this by rewriting all target va-arg
1115    gimplification hooks to use an interface gimple_build_cond_value as described
1116    in https://gcc.gnu.org/ml/gcc-patches/2015-02/msg01194.html.  */
1117 
1118 bool
1119 gimple_find_sub_bbs (gimple_seq seq, gimple_stmt_iterator *gsi)
1120 {
1121   gimple *stmt = gsi_stmt (*gsi);
1122   basic_block bb = gimple_bb (stmt);
1123   basic_block lastbb, afterbb;
1124   int old_num_bbs = n_basic_blocks_for_fn (cfun);
1125   edge e;
1126   lastbb = make_blocks_1 (seq, bb);
1127   if (old_num_bbs == n_basic_blocks_for_fn (cfun))
1128     return false;
1129   e = split_block (bb, stmt);
1130   /* Move e->dest to come after the new basic blocks.  */
1131   afterbb = e->dest;
1132   unlink_block (afterbb);
1133   link_block (afterbb, lastbb);
1134   redirect_edge_succ (e, bb->next_bb);
1135   bb = bb->next_bb;
1136   while (bb != afterbb)
1137     {
1138       struct omp_region *cur_region = NULL;
1139       profile_count cnt = profile_count::zero ();
1140       bool all = true;
1141 
1142       int cur_omp_region_idx = 0;
1143       int mer = make_edges_bb (bb, &cur_region, &cur_omp_region_idx);
1144       gcc_assert (!mer && !cur_region);
1145       add_bb_to_loop (bb, afterbb->loop_father);
1146 
1147       edge e;
1148       edge_iterator ei;
1149       FOR_EACH_EDGE (e, ei, bb->preds)
1150 	{
1151 	  if (e->count ().initialized_p ())
1152 	    cnt += e->count ();
1153 	  else
1154 	    all = false;
1155 	}
1156       tree_guess_outgoing_edge_probabilities (bb);
1157       if (all || profile_status_for_fn (cfun) == PROFILE_READ)
1158         bb->count = cnt;
1159 
1160       bb = bb->next_bb;
1161     }
1162   return true;
1163 }
1164 
1165 /* Find the next available discriminator value for LOCUS.  The
1166    discriminator distinguishes among several basic blocks that
1167    share a common locus, allowing for more accurate sample-based
1168    profiling.  */
1169 
1170 static int
1171 next_discriminator_for_locus (location_t locus)
1172 {
1173   struct locus_discrim_map item;
1174   struct locus_discrim_map **slot;
1175 
1176   item.locus = locus;
1177   item.discriminator = 0;
1178   slot = discriminator_per_locus->find_slot_with_hash (
1179       &item, LOCATION_LINE (locus), INSERT);
1180   gcc_assert (slot);
1181   if (*slot == HTAB_EMPTY_ENTRY)
1182     {
1183       *slot = XNEW (struct locus_discrim_map);
1184       gcc_assert (*slot);
1185       (*slot)->locus = locus;
1186       (*slot)->discriminator = 0;
1187     }
1188   (*slot)->discriminator++;
1189   return (*slot)->discriminator;
1190 }
1191 
1192 /* Return TRUE if LOCUS1 and LOCUS2 refer to the same source line.  */
1193 
1194 static bool
1195 same_line_p (location_t locus1, location_t locus2)
1196 {
1197   expanded_location from, to;
1198 
1199   if (locus1 == locus2)
1200     return true;
1201 
1202   from = expand_location (locus1);
1203   to = expand_location (locus2);
1204 
1205   if (from.line != to.line)
1206     return false;
1207   if (from.file == to.file)
1208     return true;
1209   return (from.file != NULL
1210           && to.file != NULL
1211           && filename_cmp (from.file, to.file) == 0);
1212 }
1213 
1214 /* Assign discriminators to each basic block.  */
1215 
1216 static void
1217 assign_discriminators (void)
1218 {
1219   basic_block bb;
1220 
1221   FOR_EACH_BB_FN (bb, cfun)
1222     {
1223       edge e;
1224       edge_iterator ei;
1225       gimple *last = last_stmt (bb);
1226       location_t locus = last ? gimple_location (last) : UNKNOWN_LOCATION;
1227 
1228       if (locus == UNKNOWN_LOCATION)
1229 	continue;
1230 
1231       FOR_EACH_EDGE (e, ei, bb->succs)
1232 	{
1233 	  gimple *first = first_non_label_stmt (e->dest);
1234 	  gimple *last = last_stmt (e->dest);
1235 	  if ((first && same_line_p (locus, gimple_location (first)))
1236 	      || (last && same_line_p (locus, gimple_location (last))))
1237 	    {
1238 	      if (e->dest->discriminator != 0 && bb->discriminator == 0)
1239 		bb->discriminator = next_discriminator_for_locus (locus);
1240 	      else
1241 		e->dest->discriminator = next_discriminator_for_locus (locus);
1242 	    }
1243 	}
1244     }
1245 }
1246 
1247 /* Create the edges for a GIMPLE_COND starting at block BB.  */
1248 
1249 static void
1250 make_cond_expr_edges (basic_block bb)
1251 {
1252   gcond *entry = as_a <gcond *> (last_stmt (bb));
1253   gimple *then_stmt, *else_stmt;
1254   basic_block then_bb, else_bb;
1255   tree then_label, else_label;
1256   edge e;
1257 
1258   gcc_assert (entry);
1259   gcc_assert (gimple_code (entry) == GIMPLE_COND);
1260 
1261   /* Entry basic blocks for each component.  */
1262   then_label = gimple_cond_true_label (entry);
1263   else_label = gimple_cond_false_label (entry);
1264   then_bb = label_to_block (then_label);
1265   else_bb = label_to_block (else_label);
1266   then_stmt = first_stmt (then_bb);
1267   else_stmt = first_stmt (else_bb);
1268 
1269   e = make_edge (bb, then_bb, EDGE_TRUE_VALUE);
1270   e->goto_locus = gimple_location (then_stmt);
1271   e = make_edge (bb, else_bb, EDGE_FALSE_VALUE);
1272   if (e)
1273     e->goto_locus = gimple_location (else_stmt);
1274 
1275   /* We do not need the labels anymore.  */
1276   gimple_cond_set_true_label (entry, NULL_TREE);
1277   gimple_cond_set_false_label (entry, NULL_TREE);
1278 }
1279 
1280 
1281 /* Called for each element in the hash table (P) as we delete the
1282    edge to cases hash table.
1283 
1284    Clear all the CASE_CHAINs to prevent problems with copying of
1285    SWITCH_EXPRs and structure sharing rules, then free the hash table
1286    element.  */
1287 
1288 bool
1289 edge_to_cases_cleanup (edge const &, tree const &value, void *)
1290 {
1291   tree t, next;
1292 
1293   for (t = value; t; t = next)
1294     {
1295       next = CASE_CHAIN (t);
1296       CASE_CHAIN (t) = NULL;
1297     }
1298 
1299   return true;
1300 }
1301 
1302 /* Start recording information mapping edges to case labels.  */
1303 
1304 void
1305 start_recording_case_labels (void)
1306 {
1307   gcc_assert (edge_to_cases == NULL);
1308   edge_to_cases = new hash_map<edge, tree>;
1309   touched_switch_bbs = BITMAP_ALLOC (NULL);
1310 }
1311 
1312 /* Return nonzero if we are recording information for case labels.  */
1313 
1314 static bool
1315 recording_case_labels_p (void)
1316 {
1317   return (edge_to_cases != NULL);
1318 }
1319 
1320 /* Stop recording information mapping edges to case labels and
1321    remove any information we have recorded.  */
1322 void
1323 end_recording_case_labels (void)
1324 {
1325   bitmap_iterator bi;
1326   unsigned i;
1327   edge_to_cases->traverse<void *, edge_to_cases_cleanup> (NULL);
1328   delete edge_to_cases;
1329   edge_to_cases = NULL;
1330   EXECUTE_IF_SET_IN_BITMAP (touched_switch_bbs, 0, i, bi)
1331     {
1332       basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i);
1333       if (bb)
1334 	{
1335 	  gimple *stmt = last_stmt (bb);
1336 	  if (stmt && gimple_code (stmt) == GIMPLE_SWITCH)
1337 	    group_case_labels_stmt (as_a <gswitch *> (stmt));
1338 	}
1339     }
1340   BITMAP_FREE (touched_switch_bbs);
1341 }
1342 
1343 /* If we are inside a {start,end}_recording_cases block, then return
1344    a chain of CASE_LABEL_EXPRs from T which reference E.
1345 
1346    Otherwise return NULL.  */
1347 
1348 static tree
1349 get_cases_for_edge (edge e, gswitch *t)
1350 {
1351   tree *slot;
1352   size_t i, n;
1353 
1354   /* If we are not recording cases, then we do not have CASE_LABEL_EXPR
1355      chains available.  Return NULL so the caller can detect this case.  */
1356   if (!recording_case_labels_p ())
1357     return NULL;
1358 
1359   slot = edge_to_cases->get (e);
1360   if (slot)
1361     return *slot;
1362 
1363   /* If we did not find E in the hash table, then this must be the first
1364      time we have been queried for information about E & T.  Add all the
1365      elements from T to the hash table then perform the query again.  */
1366 
1367   n = gimple_switch_num_labels (t);
1368   for (i = 0; i < n; i++)
1369     {
1370       tree elt = gimple_switch_label (t, i);
1371       tree lab = CASE_LABEL (elt);
1372       basic_block label_bb = label_to_block (lab);
1373       edge this_edge = find_edge (e->src, label_bb);
1374 
1375       /* Add it to the chain of CASE_LABEL_EXPRs referencing E, or create
1376 	 a new chain.  */
1377       tree &s = edge_to_cases->get_or_insert (this_edge);
1378       CASE_CHAIN (elt) = s;
1379       s = elt;
1380     }
1381 
1382   return *edge_to_cases->get (e);
1383 }
1384 
1385 /* Create the edges for a GIMPLE_SWITCH starting at block BB.  */
1386 
1387 static void
1388 make_gimple_switch_edges (gswitch *entry, basic_block bb)
1389 {
1390   size_t i, n;
1391 
1392   n = gimple_switch_num_labels (entry);
1393 
1394   for (i = 0; i < n; ++i)
1395     {
1396       tree lab = CASE_LABEL (gimple_switch_label (entry, i));
1397       basic_block label_bb = label_to_block (lab);
1398       make_edge (bb, label_bb, 0);
1399     }
1400 }
1401 
1402 
1403 /* Return the basic block holding label DEST.  */
1404 
1405 basic_block
1406 label_to_block_fn (struct function *ifun, tree dest)
1407 {
1408   int uid = LABEL_DECL_UID (dest);
1409 
1410   /* We would die hard when faced by an undefined label.  Emit a label to
1411      the very first basic block.  This will hopefully make even the dataflow
1412      and undefined variable warnings quite right.  */
1413   if (seen_error () && uid < 0)
1414     {
1415       gimple_stmt_iterator gsi =
1416 	gsi_start_bb (BASIC_BLOCK_FOR_FN (cfun, NUM_FIXED_BLOCKS));
1417       gimple *stmt;
1418 
1419       stmt = gimple_build_label (dest);
1420       gsi_insert_before (&gsi, stmt, GSI_NEW_STMT);
1421       uid = LABEL_DECL_UID (dest);
1422     }
1423   if (vec_safe_length (ifun->cfg->x_label_to_block_map) <= (unsigned int) uid)
1424     return NULL;
1425   return (*ifun->cfg->x_label_to_block_map)[uid];
1426 }
1427 
1428 /* Create edges for a goto statement at block BB.  Returns true
1429    if abnormal edges should be created.  */
1430 
1431 static bool
1432 make_goto_expr_edges (basic_block bb)
1433 {
1434   gimple_stmt_iterator last = gsi_last_bb (bb);
1435   gimple *goto_t = gsi_stmt (last);
1436 
1437   /* A simple GOTO creates normal edges.  */
1438   if (simple_goto_p (goto_t))
1439     {
1440       tree dest = gimple_goto_dest (goto_t);
1441       basic_block label_bb = label_to_block (dest);
1442       edge e = make_edge (bb, label_bb, EDGE_FALLTHRU);
1443       e->goto_locus = gimple_location (goto_t);
1444       gsi_remove (&last, true);
1445       return false;
1446     }
1447 
1448   /* A computed GOTO creates abnormal edges.  */
1449   return true;
1450 }
1451 
1452 /* Create edges for an asm statement with labels at block BB.  */
1453 
1454 static void
1455 make_gimple_asm_edges (basic_block bb)
1456 {
1457   gasm *stmt = as_a <gasm *> (last_stmt (bb));
1458   int i, n = gimple_asm_nlabels (stmt);
1459 
1460   for (i = 0; i < n; ++i)
1461     {
1462       tree label = TREE_VALUE (gimple_asm_label_op (stmt, i));
1463       basic_block label_bb = label_to_block (label);
1464       make_edge (bb, label_bb, 0);
1465     }
1466 }
1467 
1468 /*---------------------------------------------------------------------------
1469 			       Flowgraph analysis
1470 ---------------------------------------------------------------------------*/
1471 
1472 /* Cleanup useless labels in basic blocks.  This is something we wish
1473    to do early because it allows us to group case labels before creating
1474    the edges for the CFG, and it speeds up block statement iterators in
1475    all passes later on.
1476    We rerun this pass after CFG is created, to get rid of the labels that
1477    are no longer referenced.  After then we do not run it any more, since
1478    (almost) no new labels should be created.  */
1479 
1480 /* A map from basic block index to the leading label of that block.  */
1481 static struct label_record
1482 {
1483   /* The label.  */
1484   tree label;
1485 
1486   /* True if the label is referenced from somewhere.  */
1487   bool used;
1488 } *label_for_bb;
1489 
1490 /* Given LABEL return the first label in the same basic block.  */
1491 
1492 static tree
1493 main_block_label (tree label)
1494 {
1495   basic_block bb = label_to_block (label);
1496   tree main_label = label_for_bb[bb->index].label;
1497 
1498   /* label_to_block possibly inserted undefined label into the chain.  */
1499   if (!main_label)
1500     {
1501       label_for_bb[bb->index].label = label;
1502       main_label = label;
1503     }
1504 
1505   label_for_bb[bb->index].used = true;
1506   return main_label;
1507 }
1508 
1509 /* Clean up redundant labels within the exception tree.  */
1510 
1511 static void
1512 cleanup_dead_labels_eh (void)
1513 {
1514   eh_landing_pad lp;
1515   eh_region r;
1516   tree lab;
1517   int i;
1518 
1519   if (cfun->eh == NULL)
1520     return;
1521 
1522   for (i = 1; vec_safe_iterate (cfun->eh->lp_array, i, &lp); ++i)
1523     if (lp && lp->post_landing_pad)
1524       {
1525 	lab = main_block_label (lp->post_landing_pad);
1526 	if (lab != lp->post_landing_pad)
1527 	  {
1528 	    EH_LANDING_PAD_NR (lp->post_landing_pad) = 0;
1529 	    EH_LANDING_PAD_NR (lab) = lp->index;
1530 	  }
1531       }
1532 
1533   FOR_ALL_EH_REGION (r)
1534     switch (r->type)
1535       {
1536       case ERT_CLEANUP:
1537       case ERT_MUST_NOT_THROW:
1538 	break;
1539 
1540       case ERT_TRY:
1541 	{
1542 	  eh_catch c;
1543 	  for (c = r->u.eh_try.first_catch; c ; c = c->next_catch)
1544 	    {
1545 	      lab = c->label;
1546 	      if (lab)
1547 		c->label = main_block_label (lab);
1548 	    }
1549 	}
1550 	break;
1551 
1552       case ERT_ALLOWED_EXCEPTIONS:
1553 	lab = r->u.allowed.label;
1554 	if (lab)
1555 	  r->u.allowed.label = main_block_label (lab);
1556 	break;
1557       }
1558 }
1559 
1560 
1561 /* Cleanup redundant labels.  This is a three-step process:
1562      1) Find the leading label for each block.
1563      2) Redirect all references to labels to the leading labels.
1564      3) Cleanup all useless labels.  */
1565 
1566 void
1567 cleanup_dead_labels (void)
1568 {
1569   basic_block bb;
1570   label_for_bb = XCNEWVEC (struct label_record, last_basic_block_for_fn (cfun));
1571 
1572   /* Find a suitable label for each block.  We use the first user-defined
1573      label if there is one, or otherwise just the first label we see.  */
1574   FOR_EACH_BB_FN (bb, cfun)
1575     {
1576       gimple_stmt_iterator i;
1577 
1578       for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
1579 	{
1580 	  tree label;
1581 	  glabel *label_stmt = dyn_cast <glabel *> (gsi_stmt (i));
1582 
1583 	  if (!label_stmt)
1584 	    break;
1585 
1586 	  label = gimple_label_label (label_stmt);
1587 
1588 	  /* If we have not yet seen a label for the current block,
1589 	     remember this one and see if there are more labels.  */
1590 	  if (!label_for_bb[bb->index].label)
1591 	    {
1592 	      label_for_bb[bb->index].label = label;
1593 	      continue;
1594 	    }
1595 
1596 	  /* If we did see a label for the current block already, but it
1597 	     is an artificially created label, replace it if the current
1598 	     label is a user defined label.  */
1599 	  if (!DECL_ARTIFICIAL (label)
1600 	      && DECL_ARTIFICIAL (label_for_bb[bb->index].label))
1601 	    {
1602 	      label_for_bb[bb->index].label = label;
1603 	      break;
1604 	    }
1605 	}
1606     }
1607 
1608   /* Now redirect all jumps/branches to the selected label.
1609      First do so for each block ending in a control statement.  */
1610   FOR_EACH_BB_FN (bb, cfun)
1611     {
1612       gimple *stmt = last_stmt (bb);
1613       tree label, new_label;
1614 
1615       if (!stmt)
1616 	continue;
1617 
1618       switch (gimple_code (stmt))
1619 	{
1620 	case GIMPLE_COND:
1621 	  {
1622 	    gcond *cond_stmt = as_a <gcond *> (stmt);
1623 	    label = gimple_cond_true_label (cond_stmt);
1624 	    if (label)
1625 	      {
1626 		new_label = main_block_label (label);
1627 		if (new_label != label)
1628 		  gimple_cond_set_true_label (cond_stmt, new_label);
1629 	      }
1630 
1631 	    label = gimple_cond_false_label (cond_stmt);
1632 	    if (label)
1633 	      {
1634 		new_label = main_block_label (label);
1635 		if (new_label != label)
1636 		  gimple_cond_set_false_label (cond_stmt, new_label);
1637 	      }
1638 	  }
1639 	  break;
1640 
1641 	case GIMPLE_SWITCH:
1642 	  {
1643 	    gswitch *switch_stmt = as_a <gswitch *> (stmt);
1644 	    size_t i, n = gimple_switch_num_labels (switch_stmt);
1645 
1646 	    /* Replace all destination labels.  */
1647 	    for (i = 0; i < n; ++i)
1648 	      {
1649 		tree case_label = gimple_switch_label (switch_stmt, i);
1650 		label = CASE_LABEL (case_label);
1651 		new_label = main_block_label (label);
1652 		if (new_label != label)
1653 		  CASE_LABEL (case_label) = new_label;
1654 	      }
1655 	    break;
1656 	  }
1657 
1658 	case GIMPLE_ASM:
1659 	  {
1660 	    gasm *asm_stmt = as_a <gasm *> (stmt);
1661 	    int i, n = gimple_asm_nlabels (asm_stmt);
1662 
1663 	    for (i = 0; i < n; ++i)
1664 	      {
1665 		tree cons = gimple_asm_label_op (asm_stmt, i);
1666 		tree label = main_block_label (TREE_VALUE (cons));
1667 		TREE_VALUE (cons) = label;
1668 	      }
1669 	    break;
1670 	  }
1671 
1672 	/* We have to handle gotos until they're removed, and we don't
1673 	   remove them until after we've created the CFG edges.  */
1674 	case GIMPLE_GOTO:
1675 	  if (!computed_goto_p (stmt))
1676 	    {
1677 	      ggoto *goto_stmt = as_a <ggoto *> (stmt);
1678 	      label = gimple_goto_dest (goto_stmt);
1679 	      new_label = main_block_label (label);
1680 	      if (new_label != label)
1681 		gimple_goto_set_dest (goto_stmt, new_label);
1682 	    }
1683 	  break;
1684 
1685 	case GIMPLE_TRANSACTION:
1686 	  {
1687 	    gtransaction *txn = as_a <gtransaction *> (stmt);
1688 
1689 	    label = gimple_transaction_label_norm (txn);
1690 	    if (label)
1691 	      {
1692 		new_label = main_block_label (label);
1693 		if (new_label != label)
1694 		  gimple_transaction_set_label_norm (txn, new_label);
1695 	      }
1696 
1697 	    label = gimple_transaction_label_uninst (txn);
1698 	    if (label)
1699 	      {
1700 		new_label = main_block_label (label);
1701 		if (new_label != label)
1702 		  gimple_transaction_set_label_uninst (txn, new_label);
1703 	      }
1704 
1705 	    label = gimple_transaction_label_over (txn);
1706 	    if (label)
1707 	      {
1708 		new_label = main_block_label (label);
1709 		if (new_label != label)
1710 		  gimple_transaction_set_label_over (txn, new_label);
1711 	      }
1712 	  }
1713 	  break;
1714 
1715 	default:
1716 	  break;
1717       }
1718     }
1719 
1720   /* Do the same for the exception region tree labels.  */
1721   cleanup_dead_labels_eh ();
1722 
1723   /* Finally, purge dead labels.  All user-defined labels and labels that
1724      can be the target of non-local gotos and labels which have their
1725      address taken are preserved.  */
1726   FOR_EACH_BB_FN (bb, cfun)
1727     {
1728       gimple_stmt_iterator i;
1729       tree label_for_this_bb = label_for_bb[bb->index].label;
1730 
1731       if (!label_for_this_bb)
1732 	continue;
1733 
1734       /* If the main label of the block is unused, we may still remove it.  */
1735       if (!label_for_bb[bb->index].used)
1736 	label_for_this_bb = NULL;
1737 
1738       for (i = gsi_start_bb (bb); !gsi_end_p (i); )
1739 	{
1740 	  tree label;
1741 	  glabel *label_stmt = dyn_cast <glabel *> (gsi_stmt (i));
1742 
1743 	  if (!label_stmt)
1744 	    break;
1745 
1746 	  label = gimple_label_label (label_stmt);
1747 
1748 	  if (label == label_for_this_bb
1749 	      || !DECL_ARTIFICIAL (label)
1750 	      || DECL_NONLOCAL (label)
1751 	      || FORCED_LABEL (label))
1752 	    gsi_next (&i);
1753 	  else
1754 	    gsi_remove (&i, true);
1755 	}
1756     }
1757 
1758   free (label_for_bb);
1759 }
1760 
1761 /* Scan the sorted vector of cases in STMT (a GIMPLE_SWITCH) and combine
1762    the ones jumping to the same label.
1763    Eg. three separate entries 1: 2: 3: become one entry 1..3:  */
1764 
1765 bool
1766 group_case_labels_stmt (gswitch *stmt)
1767 {
1768   int old_size = gimple_switch_num_labels (stmt);
1769   int i, next_index, new_size;
1770   basic_block default_bb = NULL;
1771 
1772   default_bb = label_to_block (CASE_LABEL (gimple_switch_default_label (stmt)));
1773 
1774   /* Look for possible opportunities to merge cases.  */
1775   new_size = i = 1;
1776   while (i < old_size)
1777     {
1778       tree base_case, base_high;
1779       basic_block base_bb;
1780 
1781       base_case = gimple_switch_label (stmt, i);
1782 
1783       gcc_assert (base_case);
1784       base_bb = label_to_block (CASE_LABEL (base_case));
1785 
1786       /* Discard cases that have the same destination as the default case or
1787 	 whose destiniation blocks have already been removed as unreachable.  */
1788       if (base_bb == NULL || base_bb == default_bb)
1789 	{
1790 	  i++;
1791 	  continue;
1792 	}
1793 
1794       base_high = CASE_HIGH (base_case)
1795 	  ? CASE_HIGH (base_case)
1796 	  : CASE_LOW (base_case);
1797       next_index = i + 1;
1798 
1799       /* Try to merge case labels.  Break out when we reach the end
1800 	 of the label vector or when we cannot merge the next case
1801 	 label with the current one.  */
1802       while (next_index < old_size)
1803 	{
1804 	  tree merge_case = gimple_switch_label (stmt, next_index);
1805 	  basic_block merge_bb = label_to_block (CASE_LABEL (merge_case));
1806 	  wide_int bhp1 = wi::to_wide (base_high) + 1;
1807 
1808 	  /* Merge the cases if they jump to the same place,
1809 	     and their ranges are consecutive.  */
1810 	  if (merge_bb == base_bb
1811 	      && wi::to_wide (CASE_LOW (merge_case)) == bhp1)
1812 	    {
1813 	      base_high = CASE_HIGH (merge_case) ?
1814 		  CASE_HIGH (merge_case) : CASE_LOW (merge_case);
1815 	      CASE_HIGH (base_case) = base_high;
1816 	      next_index++;
1817 	    }
1818 	  else
1819 	    break;
1820 	}
1821 
1822       /* Discard cases that have an unreachable destination block.  */
1823       if (EDGE_COUNT (base_bb->succs) == 0
1824 	  && gimple_seq_unreachable_p (bb_seq (base_bb))
1825 	  /* Don't optimize this if __builtin_unreachable () is the
1826 	     implicitly added one by the C++ FE too early, before
1827 	     -Wreturn-type can be diagnosed.  We'll optimize it later
1828 	     during switchconv pass or any other cfg cleanup.  */
1829 	  && (gimple_in_ssa_p (cfun)
1830 	      || (LOCATION_LOCUS (gimple_location (last_stmt (base_bb)))
1831 		  != BUILTINS_LOCATION)))
1832 	{
1833 	  edge base_edge = find_edge (gimple_bb (stmt), base_bb);
1834 	  if (base_edge != NULL)
1835 	    remove_edge_and_dominated_blocks (base_edge);
1836 	  i = next_index;
1837 	  continue;
1838 	}
1839 
1840       if (new_size < i)
1841 	gimple_switch_set_label (stmt, new_size,
1842 				 gimple_switch_label (stmt, i));
1843       i = next_index;
1844       new_size++;
1845     }
1846 
1847   gcc_assert (new_size <= old_size);
1848 
1849   if (new_size < old_size)
1850     gimple_switch_set_num_labels (stmt, new_size);
1851 
1852   return new_size < old_size;
1853 }
1854 
1855 /* Look for blocks ending in a multiway branch (a GIMPLE_SWITCH),
1856    and scan the sorted vector of cases.  Combine the ones jumping to the
1857    same label.  */
1858 
1859 bool
1860 group_case_labels (void)
1861 {
1862   basic_block bb;
1863   bool changed = false;
1864 
1865   FOR_EACH_BB_FN (bb, cfun)
1866     {
1867       gimple *stmt = last_stmt (bb);
1868       if (stmt && gimple_code (stmt) == GIMPLE_SWITCH)
1869 	changed |= group_case_labels_stmt (as_a <gswitch *> (stmt));
1870     }
1871 
1872   return changed;
1873 }
1874 
1875 /* Checks whether we can merge block B into block A.  */
1876 
1877 static bool
1878 gimple_can_merge_blocks_p (basic_block a, basic_block b)
1879 {
1880   gimple *stmt;
1881 
1882   if (!single_succ_p (a))
1883     return false;
1884 
1885   if (single_succ_edge (a)->flags & EDGE_COMPLEX)
1886     return false;
1887 
1888   if (single_succ (a) != b)
1889     return false;
1890 
1891   if (!single_pred_p (b))
1892     return false;
1893 
1894   if (a == ENTRY_BLOCK_PTR_FOR_FN (cfun)
1895       || b == EXIT_BLOCK_PTR_FOR_FN (cfun))
1896     return false;
1897 
1898   /* If A ends by a statement causing exceptions or something similar, we
1899      cannot merge the blocks.  */
1900   stmt = last_stmt (a);
1901   if (stmt && stmt_ends_bb_p (stmt))
1902     return false;
1903 
1904   /* Do not allow a block with only a non-local label to be merged.  */
1905   if (stmt)
1906     if (glabel *label_stmt = dyn_cast <glabel *> (stmt))
1907       if (DECL_NONLOCAL (gimple_label_label (label_stmt)))
1908 	return false;
1909 
1910   /* Examine the labels at the beginning of B.  */
1911   for (gimple_stmt_iterator gsi = gsi_start_bb (b); !gsi_end_p (gsi);
1912        gsi_next (&gsi))
1913     {
1914       tree lab;
1915       glabel *label_stmt = dyn_cast <glabel *> (gsi_stmt (gsi));
1916       if (!label_stmt)
1917 	break;
1918       lab = gimple_label_label (label_stmt);
1919 
1920       /* Do not remove user forced labels or for -O0 any user labels.  */
1921       if (!DECL_ARTIFICIAL (lab) && (!optimize || FORCED_LABEL (lab)))
1922 	return false;
1923     }
1924 
1925   /* Protect simple loop latches.  We only want to avoid merging
1926      the latch with the loop header or with a block in another
1927      loop in this case.  */
1928   if (current_loops
1929       && b->loop_father->latch == b
1930       && loops_state_satisfies_p (LOOPS_HAVE_SIMPLE_LATCHES)
1931       && (b->loop_father->header == a
1932 	  || b->loop_father != a->loop_father))
1933     return false;
1934 
1935   /* It must be possible to eliminate all phi nodes in B.  If ssa form
1936      is not up-to-date and a name-mapping is registered, we cannot eliminate
1937      any phis.  Symbols marked for renaming are never a problem though.  */
1938   for (gphi_iterator gsi = gsi_start_phis (b); !gsi_end_p (gsi);
1939        gsi_next (&gsi))
1940     {
1941       gphi *phi = gsi.phi ();
1942       /* Technically only new names matter.  */
1943       if (name_registered_for_update_p (PHI_RESULT (phi)))
1944 	return false;
1945     }
1946 
1947   /* When not optimizing, don't merge if we'd lose goto_locus.  */
1948   if (!optimize
1949       && single_succ_edge (a)->goto_locus != UNKNOWN_LOCATION)
1950     {
1951       location_t goto_locus = single_succ_edge (a)->goto_locus;
1952       gimple_stmt_iterator prev, next;
1953       prev = gsi_last_nondebug_bb (a);
1954       next = gsi_after_labels (b);
1955       if (!gsi_end_p (next) && is_gimple_debug (gsi_stmt (next)))
1956 	gsi_next_nondebug (&next);
1957       if ((gsi_end_p (prev)
1958 	   || gimple_location (gsi_stmt (prev)) != goto_locus)
1959 	  && (gsi_end_p (next)
1960 	      || gimple_location (gsi_stmt (next)) != goto_locus))
1961 	return false;
1962     }
1963 
1964   return true;
1965 }
1966 
1967 /* Replaces all uses of NAME by VAL.  */
1968 
1969 void
1970 replace_uses_by (tree name, tree val)
1971 {
1972   imm_use_iterator imm_iter;
1973   use_operand_p use;
1974   gimple *stmt;
1975   edge e;
1976 
1977   FOR_EACH_IMM_USE_STMT (stmt, imm_iter, name)
1978     {
1979       /* Mark the block if we change the last stmt in it.  */
1980       if (cfgcleanup_altered_bbs
1981 	  && stmt_ends_bb_p (stmt))
1982 	bitmap_set_bit (cfgcleanup_altered_bbs, gimple_bb (stmt)->index);
1983 
1984       FOR_EACH_IMM_USE_ON_STMT (use, imm_iter)
1985         {
1986 	  replace_exp (use, val);
1987 
1988 	  if (gimple_code (stmt) == GIMPLE_PHI)
1989 	    {
1990 	      e = gimple_phi_arg_edge (as_a <gphi *> (stmt),
1991 				       PHI_ARG_INDEX_FROM_USE (use));
1992 	      if (e->flags & EDGE_ABNORMAL
1993 		  && !SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val))
1994 		{
1995 		  /* This can only occur for virtual operands, since
1996 		     for the real ones SSA_NAME_OCCURS_IN_ABNORMAL_PHI (name))
1997 		     would prevent replacement.  */
1998 		  gcc_checking_assert (virtual_operand_p (name));
1999 		  SSA_NAME_OCCURS_IN_ABNORMAL_PHI (val) = 1;
2000 		}
2001 	    }
2002 	}
2003 
2004       if (gimple_code (stmt) != GIMPLE_PHI)
2005 	{
2006 	  gimple_stmt_iterator gsi = gsi_for_stmt (stmt);
2007 	  gimple *orig_stmt = stmt;
2008 	  size_t i;
2009 
2010 	  /* FIXME.  It shouldn't be required to keep TREE_CONSTANT
2011 	     on ADDR_EXPRs up-to-date on GIMPLE.  Propagation will
2012 	     only change sth from non-invariant to invariant, and only
2013 	     when propagating constants.  */
2014 	  if (is_gimple_min_invariant (val))
2015 	    for (i = 0; i < gimple_num_ops (stmt); i++)
2016 	      {
2017 		tree op = gimple_op (stmt, i);
2018 		/* Operands may be empty here.  For example, the labels
2019 		   of a GIMPLE_COND are nulled out following the creation
2020 		   of the corresponding CFG edges.  */
2021 		if (op && TREE_CODE (op) == ADDR_EXPR)
2022 		  recompute_tree_invariant_for_addr_expr (op);
2023 	      }
2024 
2025 	  if (fold_stmt (&gsi))
2026 	    stmt = gsi_stmt (gsi);
2027 
2028 	  if (maybe_clean_or_replace_eh_stmt (orig_stmt, stmt))
2029 	    gimple_purge_dead_eh_edges (gimple_bb (stmt));
2030 
2031 	  update_stmt (stmt);
2032 	}
2033     }
2034 
2035   gcc_checking_assert (has_zero_uses (name));
2036 
2037   /* Also update the trees stored in loop structures.  */
2038   if (current_loops)
2039     {
2040       struct loop *loop;
2041 
2042       FOR_EACH_LOOP (loop, 0)
2043 	{
2044 	  substitute_in_loop_info (loop, name, val);
2045 	}
2046     }
2047 }
2048 
2049 /* Merge block B into block A.  */
2050 
2051 static void
2052 gimple_merge_blocks (basic_block a, basic_block b)
2053 {
2054   gimple_stmt_iterator last, gsi;
2055   gphi_iterator psi;
2056 
2057   if (dump_file)
2058     fprintf (dump_file, "Merging blocks %d and %d\n", a->index, b->index);
2059 
2060   /* Remove all single-valued PHI nodes from block B of the form
2061      V_i = PHI <V_j> by propagating V_j to all the uses of V_i.  */
2062   gsi = gsi_last_bb (a);
2063   for (psi = gsi_start_phis (b); !gsi_end_p (psi); )
2064     {
2065       gimple *phi = gsi_stmt (psi);
2066       tree def = gimple_phi_result (phi), use = gimple_phi_arg_def (phi, 0);
2067       gimple *copy;
2068       bool may_replace_uses = (virtual_operand_p (def)
2069 			       || may_propagate_copy (def, use));
2070 
2071       /* In case we maintain loop closed ssa form, do not propagate arguments
2072 	 of loop exit phi nodes.  */
2073       if (current_loops
2074 	  && loops_state_satisfies_p (LOOP_CLOSED_SSA)
2075 	  && !virtual_operand_p (def)
2076 	  && TREE_CODE (use) == SSA_NAME
2077 	  && a->loop_father != b->loop_father)
2078 	may_replace_uses = false;
2079 
2080       if (!may_replace_uses)
2081 	{
2082 	  gcc_assert (!virtual_operand_p (def));
2083 
2084 	  /* Note that just emitting the copies is fine -- there is no problem
2085 	     with ordering of phi nodes.  This is because A is the single
2086 	     predecessor of B, therefore results of the phi nodes cannot
2087 	     appear as arguments of the phi nodes.  */
2088 	  copy = gimple_build_assign (def, use);
2089 	  gsi_insert_after (&gsi, copy, GSI_NEW_STMT);
2090           remove_phi_node (&psi, false);
2091 	}
2092       else
2093         {
2094 	  /* If we deal with a PHI for virtual operands, we can simply
2095 	     propagate these without fussing with folding or updating
2096 	     the stmt.  */
2097 	  if (virtual_operand_p (def))
2098 	    {
2099 	      imm_use_iterator iter;
2100 	      use_operand_p use_p;
2101 	      gimple *stmt;
2102 
2103 	      FOR_EACH_IMM_USE_STMT (stmt, iter, def)
2104 		FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
2105 		  SET_USE (use_p, use);
2106 
2107 	      if (SSA_NAME_OCCURS_IN_ABNORMAL_PHI (def))
2108 		SSA_NAME_OCCURS_IN_ABNORMAL_PHI (use) = 1;
2109 	    }
2110 	  else
2111             replace_uses_by (def, use);
2112 
2113           remove_phi_node (&psi, true);
2114         }
2115     }
2116 
2117   /* Ensure that B follows A.  */
2118   move_block_after (b, a);
2119 
2120   gcc_assert (single_succ_edge (a)->flags & EDGE_FALLTHRU);
2121   gcc_assert (!last_stmt (a) || !stmt_ends_bb_p (last_stmt (a)));
2122 
2123   /* Remove labels from B and set gimple_bb to A for other statements.  */
2124   for (gsi = gsi_start_bb (b); !gsi_end_p (gsi);)
2125     {
2126       gimple *stmt = gsi_stmt (gsi);
2127       if (glabel *label_stmt = dyn_cast <glabel *> (stmt))
2128 	{
2129 	  tree label = gimple_label_label (label_stmt);
2130 	  int lp_nr;
2131 
2132 	  gsi_remove (&gsi, false);
2133 
2134 	  /* Now that we can thread computed gotos, we might have
2135 	     a situation where we have a forced label in block B
2136 	     However, the label at the start of block B might still be
2137 	     used in other ways (think about the runtime checking for
2138 	     Fortran assigned gotos).  So we can not just delete the
2139 	     label.  Instead we move the label to the start of block A.  */
2140 	  if (FORCED_LABEL (label))
2141 	    {
2142 	      gimple_stmt_iterator dest_gsi = gsi_start_bb (a);
2143 	      gsi_insert_before (&dest_gsi, stmt, GSI_NEW_STMT);
2144 	    }
2145 	  /* Other user labels keep around in a form of a debug stmt.  */
2146 	  else if (!DECL_ARTIFICIAL (label) && MAY_HAVE_DEBUG_BIND_STMTS)
2147 	    {
2148 	      gimple *dbg = gimple_build_debug_bind (label,
2149 						     integer_zero_node,
2150 						     stmt);
2151 	      gimple_debug_bind_reset_value (dbg);
2152 	      gsi_insert_before (&gsi, dbg, GSI_SAME_STMT);
2153 	    }
2154 
2155 	  lp_nr = EH_LANDING_PAD_NR (label);
2156 	  if (lp_nr)
2157 	    {
2158 	      eh_landing_pad lp = get_eh_landing_pad_from_number (lp_nr);
2159 	      lp->post_landing_pad = NULL;
2160 	    }
2161 	}
2162       else
2163 	{
2164 	  gimple_set_bb (stmt, a);
2165 	  gsi_next (&gsi);
2166 	}
2167     }
2168 
2169   /* When merging two BBs, if their counts are different, the larger count
2170      is selected as the new bb count. This is to handle inconsistent
2171      profiles.  */
2172   if (a->loop_father == b->loop_father)
2173     {
2174       a->count = a->count.merge (b->count);
2175     }
2176 
2177   /* Merge the sequences.  */
2178   last = gsi_last_bb (a);
2179   gsi_insert_seq_after (&last, bb_seq (b), GSI_NEW_STMT);
2180   set_bb_seq (b, NULL);
2181 
2182   if (cfgcleanup_altered_bbs)
2183     bitmap_set_bit (cfgcleanup_altered_bbs, a->index);
2184 }
2185 
2186 
2187 /* Return the one of two successors of BB that is not reachable by a
2188    complex edge, if there is one.  Else, return BB.  We use
2189    this in optimizations that use post-dominators for their heuristics,
2190    to catch the cases in C++ where function calls are involved.  */
2191 
2192 basic_block
2193 single_noncomplex_succ (basic_block bb)
2194 {
2195   edge e0, e1;
2196   if (EDGE_COUNT (bb->succs) != 2)
2197     return bb;
2198 
2199   e0 = EDGE_SUCC (bb, 0);
2200   e1 = EDGE_SUCC (bb, 1);
2201   if (e0->flags & EDGE_COMPLEX)
2202     return e1->dest;
2203   if (e1->flags & EDGE_COMPLEX)
2204     return e0->dest;
2205 
2206   return bb;
2207 }
2208 
2209 /* T is CALL_EXPR.  Set current_function_calls_* flags.  */
2210 
2211 void
2212 notice_special_calls (gcall *call)
2213 {
2214   int flags = gimple_call_flags (call);
2215 
2216   if (flags & ECF_MAY_BE_ALLOCA)
2217     cfun->calls_alloca = true;
2218   if (flags & ECF_RETURNS_TWICE)
2219     cfun->calls_setjmp = true;
2220 }
2221 
2222 
2223 /* Clear flags set by notice_special_calls.  Used by dead code removal
2224    to update the flags.  */
2225 
2226 void
2227 clear_special_calls (void)
2228 {
2229   cfun->calls_alloca = false;
2230   cfun->calls_setjmp = false;
2231 }
2232 
2233 /* Remove PHI nodes associated with basic block BB and all edges out of BB.  */
2234 
2235 static void
2236 remove_phi_nodes_and_edges_for_unreachable_block (basic_block bb)
2237 {
2238   /* Since this block is no longer reachable, we can just delete all
2239      of its PHI nodes.  */
2240   remove_phi_nodes (bb);
2241 
2242   /* Remove edges to BB's successors.  */
2243   while (EDGE_COUNT (bb->succs) > 0)
2244     remove_edge (EDGE_SUCC (bb, 0));
2245 }
2246 
2247 
2248 /* Remove statements of basic block BB.  */
2249 
2250 static void
2251 remove_bb (basic_block bb)
2252 {
2253   gimple_stmt_iterator i;
2254 
2255   if (dump_file)
2256     {
2257       fprintf (dump_file, "Removing basic block %d\n", bb->index);
2258       if (dump_flags & TDF_DETAILS)
2259 	{
2260 	  dump_bb (dump_file, bb, 0, TDF_BLOCKS);
2261 	  fprintf (dump_file, "\n");
2262 	}
2263     }
2264 
2265   if (current_loops)
2266     {
2267       struct loop *loop = bb->loop_father;
2268 
2269       /* If a loop gets removed, clean up the information associated
2270 	 with it.  */
2271       if (loop->latch == bb
2272 	  || loop->header == bb)
2273 	free_numbers_of_iterations_estimates (loop);
2274     }
2275 
2276   /* Remove all the instructions in the block.  */
2277   if (bb_seq (bb) != NULL)
2278     {
2279       /* Walk backwards so as to get a chance to substitute all
2280 	 released DEFs into debug stmts.  See
2281 	 eliminate_unnecessary_stmts() in tree-ssa-dce.c for more
2282 	 details.  */
2283       for (i = gsi_last_bb (bb); !gsi_end_p (i);)
2284 	{
2285 	  gimple *stmt = gsi_stmt (i);
2286 	  glabel *label_stmt = dyn_cast <glabel *> (stmt);
2287 	  if (label_stmt
2288 	      && (FORCED_LABEL (gimple_label_label (label_stmt))
2289 		  || DECL_NONLOCAL (gimple_label_label (label_stmt))))
2290 	    {
2291 	      basic_block new_bb;
2292 	      gimple_stmt_iterator new_gsi;
2293 
2294 	      /* A non-reachable non-local label may still be referenced.
2295 		 But it no longer needs to carry the extra semantics of
2296 		 non-locality.  */
2297 	      if (DECL_NONLOCAL (gimple_label_label (label_stmt)))
2298 		{
2299 		  DECL_NONLOCAL (gimple_label_label (label_stmt)) = 0;
2300 		  FORCED_LABEL (gimple_label_label (label_stmt)) = 1;
2301 		}
2302 
2303 	      new_bb = bb->prev_bb;
2304 	      /* Don't move any labels into ENTRY block.  */
2305 	      if (new_bb == ENTRY_BLOCK_PTR_FOR_FN (cfun))
2306 		{
2307 		  new_bb = single_succ (new_bb);
2308 		  gcc_assert (new_bb != bb);
2309 		}
2310 	      new_gsi = gsi_start_bb (new_bb);
2311 	      gsi_remove (&i, false);
2312 	      gsi_insert_before (&new_gsi, stmt, GSI_NEW_STMT);
2313 	    }
2314 	  else
2315 	    {
2316 	      /* Release SSA definitions.  */
2317 	      release_defs (stmt);
2318 	      gsi_remove (&i, true);
2319 	    }
2320 
2321 	  if (gsi_end_p (i))
2322 	    i = gsi_last_bb (bb);
2323 	  else
2324 	    gsi_prev (&i);
2325 	}
2326     }
2327 
2328   remove_phi_nodes_and_edges_for_unreachable_block (bb);
2329   bb->il.gimple.seq = NULL;
2330   bb->il.gimple.phi_nodes = NULL;
2331 }
2332 
2333 
2334 /* Given a basic block BB and a value VAL for use in the final statement
2335    of the block (if a GIMPLE_COND, GIMPLE_SWITCH, or computed goto), return
2336    the edge that will be taken out of the block.
2337    If VAL is NULL_TREE, then the current value of the final statement's
2338    predicate or index is used.
2339    If the value does not match a unique edge, NULL is returned.  */
2340 
2341 edge
2342 find_taken_edge (basic_block bb, tree val)
2343 {
2344   gimple *stmt;
2345 
2346   stmt = last_stmt (bb);
2347 
2348   /* Handle ENTRY and EXIT.  */
2349   if (!stmt)
2350     return NULL;
2351 
2352   if (gimple_code (stmt) == GIMPLE_COND)
2353     return find_taken_edge_cond_expr (as_a <gcond *> (stmt), val);
2354 
2355   if (gimple_code (stmt) == GIMPLE_SWITCH)
2356     return find_taken_edge_switch_expr (as_a <gswitch *> (stmt), val);
2357 
2358   if (computed_goto_p (stmt))
2359     {
2360       /* Only optimize if the argument is a label, if the argument is
2361 	 not a label then we can not construct a proper CFG.
2362 
2363          It may be the case that we only need to allow the LABEL_REF to
2364          appear inside an ADDR_EXPR, but we also allow the LABEL_REF to
2365          appear inside a LABEL_EXPR just to be safe.  */
2366       if (val
2367 	  && (TREE_CODE (val) == ADDR_EXPR || TREE_CODE (val) == LABEL_EXPR)
2368 	  && TREE_CODE (TREE_OPERAND (val, 0)) == LABEL_DECL)
2369 	return find_taken_edge_computed_goto (bb, TREE_OPERAND (val, 0));
2370     }
2371 
2372   /* Otherwise we only know the taken successor edge if it's unique.  */
2373   return single_succ_p (bb) ? single_succ_edge (bb) : NULL;
2374 }
2375 
2376 /* Given a constant value VAL and the entry block BB to a GOTO_EXPR
2377    statement, determine which of the outgoing edges will be taken out of the
2378    block.  Return NULL if either edge may be taken.  */
2379 
2380 static edge
2381 find_taken_edge_computed_goto (basic_block bb, tree val)
2382 {
2383   basic_block dest;
2384   edge e = NULL;
2385 
2386   dest = label_to_block (val);
2387   if (dest)
2388     e = find_edge (bb, dest);
2389 
2390   /* It's possible for find_edge to return NULL here on invalid code
2391      that abuses the labels-as-values extension (e.g. code that attempts to
2392      jump *between* functions via stored labels-as-values; PR 84136).
2393      If so, then we simply return that NULL for the edge.
2394      We don't currently have a way of detecting such invalid code, so we
2395      can't assert that it was the case when a NULL edge occurs here.  */
2396 
2397   return e;
2398 }
2399 
2400 /* Given COND_STMT and a constant value VAL for use as the predicate,
2401    determine which of the two edges will be taken out of
2402    the statement's block.  Return NULL if either edge may be taken.
2403    If VAL is NULL_TREE, then the current value of COND_STMT's predicate
2404    is used.  */
2405 
2406 static edge
2407 find_taken_edge_cond_expr (const gcond *cond_stmt, tree val)
2408 {
2409   edge true_edge, false_edge;
2410 
2411   if (val == NULL_TREE)
2412     {
2413       /* Use the current value of the predicate.  */
2414       if (gimple_cond_true_p (cond_stmt))
2415 	val = integer_one_node;
2416       else if (gimple_cond_false_p (cond_stmt))
2417 	val = integer_zero_node;
2418       else
2419 	return NULL;
2420     }
2421   else if (TREE_CODE (val) != INTEGER_CST)
2422     return NULL;
2423 
2424   extract_true_false_edges_from_block (gimple_bb (cond_stmt),
2425 				       &true_edge, &false_edge);
2426 
2427   return (integer_zerop (val) ? false_edge : true_edge);
2428 }
2429 
2430 /* Given SWITCH_STMT and an INTEGER_CST VAL for use as the index, determine
2431    which edge will be taken out of the statement's block.  Return NULL if any
2432    edge may be taken.
2433    If VAL is NULL_TREE, then the current value of SWITCH_STMT's index
2434    is used.  */
2435 
2436 static edge
2437 find_taken_edge_switch_expr (const gswitch *switch_stmt, tree val)
2438 {
2439   basic_block dest_bb;
2440   edge e;
2441   tree taken_case;
2442 
2443   if (gimple_switch_num_labels (switch_stmt) == 1)
2444     taken_case = gimple_switch_default_label (switch_stmt);
2445   else
2446     {
2447       if (val == NULL_TREE)
2448 	val = gimple_switch_index (switch_stmt);
2449       if (TREE_CODE (val) != INTEGER_CST)
2450 	return NULL;
2451       else
2452 	taken_case = find_case_label_for_value (switch_stmt, val);
2453     }
2454   dest_bb = label_to_block (CASE_LABEL (taken_case));
2455 
2456   e = find_edge (gimple_bb (switch_stmt), dest_bb);
2457   gcc_assert (e);
2458   return e;
2459 }
2460 
2461 
2462 /* Return the CASE_LABEL_EXPR that SWITCH_STMT will take for VAL.
2463    We can make optimal use here of the fact that the case labels are
2464    sorted: We can do a binary search for a case matching VAL.  */
2465 
2466 static tree
2467 find_case_label_for_value (const gswitch *switch_stmt, tree val)
2468 {
2469   size_t low, high, n = gimple_switch_num_labels (switch_stmt);
2470   tree default_case = gimple_switch_default_label (switch_stmt);
2471 
2472   for (low = 0, high = n; high - low > 1; )
2473     {
2474       size_t i = (high + low) / 2;
2475       tree t = gimple_switch_label (switch_stmt, i);
2476       int cmp;
2477 
2478       /* Cache the result of comparing CASE_LOW and val.  */
2479       cmp = tree_int_cst_compare (CASE_LOW (t), val);
2480 
2481       if (cmp > 0)
2482 	high = i;
2483       else
2484 	low = i;
2485 
2486       if (CASE_HIGH (t) == NULL)
2487 	{
2488 	  /* A singe-valued case label.  */
2489 	  if (cmp == 0)
2490 	    return t;
2491 	}
2492       else
2493 	{
2494 	  /* A case range.  We can only handle integer ranges.  */
2495 	  if (cmp <= 0 && tree_int_cst_compare (CASE_HIGH (t), val) >= 0)
2496 	    return t;
2497 	}
2498     }
2499 
2500   return default_case;
2501 }
2502 
2503 
2504 /* Dump a basic block on stderr.  */
2505 
2506 void
2507 gimple_debug_bb (basic_block bb)
2508 {
2509   dump_bb (stderr, bb, 0, TDF_VOPS|TDF_MEMSYMS|TDF_BLOCKS);
2510 }
2511 
2512 
2513 /* Dump basic block with index N on stderr.  */
2514 
2515 basic_block
2516 gimple_debug_bb_n (int n)
2517 {
2518   gimple_debug_bb (BASIC_BLOCK_FOR_FN (cfun, n));
2519   return BASIC_BLOCK_FOR_FN (cfun, n);
2520 }
2521 
2522 
2523 /* Dump the CFG on stderr.
2524 
2525    FLAGS are the same used by the tree dumping functions
2526    (see TDF_* in dumpfile.h).  */
2527 
2528 void
2529 gimple_debug_cfg (dump_flags_t flags)
2530 {
2531   gimple_dump_cfg (stderr, flags);
2532 }
2533 
2534 
2535 /* Dump the program showing basic block boundaries on the given FILE.
2536 
2537    FLAGS are the same used by the tree dumping functions (see TDF_* in
2538    tree.h).  */
2539 
2540 void
2541 gimple_dump_cfg (FILE *file, dump_flags_t flags)
2542 {
2543   if (flags & TDF_DETAILS)
2544     {
2545       dump_function_header (file, current_function_decl, flags);
2546       fprintf (file, ";; \n%d basic blocks, %d edges, last basic block %d.\n\n",
2547 	       n_basic_blocks_for_fn (cfun), n_edges_for_fn (cfun),
2548 	       last_basic_block_for_fn (cfun));
2549 
2550       brief_dump_cfg (file, flags);
2551       fprintf (file, "\n");
2552     }
2553 
2554   if (flags & TDF_STATS)
2555     dump_cfg_stats (file);
2556 
2557   dump_function_to_file (current_function_decl, file, flags | TDF_BLOCKS);
2558 }
2559 
2560 
2561 /* Dump CFG statistics on FILE.  */
2562 
2563 void
2564 dump_cfg_stats (FILE *file)
2565 {
2566   static long max_num_merged_labels = 0;
2567   unsigned long size, total = 0;
2568   long num_edges;
2569   basic_block bb;
2570   const char * const fmt_str   = "%-30s%-13s%12s\n";
2571   const char * const fmt_str_1 = "%-30s%13d%11lu%c\n";
2572   const char * const fmt_str_2 = "%-30s%13ld%11lu%c\n";
2573   const char * const fmt_str_3 = "%-43s%11lu%c\n";
2574   const char *funcname = current_function_name ();
2575 
2576   fprintf (file, "\nCFG Statistics for %s\n\n", funcname);
2577 
2578   fprintf (file, "---------------------------------------------------------\n");
2579   fprintf (file, fmt_str, "", "  Number of  ", "Memory");
2580   fprintf (file, fmt_str, "", "  instances  ", "used ");
2581   fprintf (file, "---------------------------------------------------------\n");
2582 
2583   size = n_basic_blocks_for_fn (cfun) * sizeof (struct basic_block_def);
2584   total += size;
2585   fprintf (file, fmt_str_1, "Basic blocks", n_basic_blocks_for_fn (cfun),
2586 	   SCALE (size), LABEL (size));
2587 
2588   num_edges = 0;
2589   FOR_EACH_BB_FN (bb, cfun)
2590     num_edges += EDGE_COUNT (bb->succs);
2591   size = num_edges * sizeof (struct edge_def);
2592   total += size;
2593   fprintf (file, fmt_str_2, "Edges", num_edges, SCALE (size), LABEL (size));
2594 
2595   fprintf (file, "---------------------------------------------------------\n");
2596   fprintf (file, fmt_str_3, "Total memory used by CFG data", SCALE (total),
2597 	   LABEL (total));
2598   fprintf (file, "---------------------------------------------------------\n");
2599   fprintf (file, "\n");
2600 
2601   if (cfg_stats.num_merged_labels > max_num_merged_labels)
2602     max_num_merged_labels = cfg_stats.num_merged_labels;
2603 
2604   fprintf (file, "Coalesced label blocks: %ld (Max so far: %ld)\n",
2605 	   cfg_stats.num_merged_labels, max_num_merged_labels);
2606 
2607   fprintf (file, "\n");
2608 }
2609 
2610 
2611 /* Dump CFG statistics on stderr.  Keep extern so that it's always
2612    linked in the final executable.  */
2613 
2614 DEBUG_FUNCTION void
2615 debug_cfg_stats (void)
2616 {
2617   dump_cfg_stats (stderr);
2618 }
2619 
2620 /*---------------------------------------------------------------------------
2621 			     Miscellaneous helpers
2622 ---------------------------------------------------------------------------*/
2623 
2624 /* Return true if T, a GIMPLE_CALL, can make an abnormal transfer of control
2625    flow.  Transfers of control flow associated with EH are excluded.  */
2626 
2627 static bool
2628 call_can_make_abnormal_goto (gimple *t)
2629 {
2630   /* If the function has no non-local labels, then a call cannot make an
2631      abnormal transfer of control.  */
2632   if (!cfun->has_nonlocal_label
2633       && !cfun->calls_setjmp)
2634    return false;
2635 
2636   /* Likewise if the call has no side effects.  */
2637   if (!gimple_has_side_effects (t))
2638     return false;
2639 
2640   /* Likewise if the called function is leaf.  */
2641   if (gimple_call_flags (t) & ECF_LEAF)
2642     return false;
2643 
2644   return true;
2645 }
2646 
2647 
2648 /* Return true if T can make an abnormal transfer of control flow.
2649    Transfers of control flow associated with EH are excluded.  */
2650 
2651 bool
2652 stmt_can_make_abnormal_goto (gimple *t)
2653 {
2654   if (computed_goto_p (t))
2655     return true;
2656   if (is_gimple_call (t))
2657     return call_can_make_abnormal_goto (t);
2658   return false;
2659 }
2660 
2661 
2662 /* Return true if T represents a stmt that always transfers control.  */
2663 
2664 bool
2665 is_ctrl_stmt (gimple *t)
2666 {
2667   switch (gimple_code (t))
2668     {
2669     case GIMPLE_COND:
2670     case GIMPLE_SWITCH:
2671     case GIMPLE_GOTO:
2672     case GIMPLE_RETURN:
2673     case GIMPLE_RESX:
2674       return true;
2675     default:
2676       return false;
2677     }
2678 }
2679 
2680 
2681 /* Return true if T is a statement that may alter the flow of control
2682    (e.g., a call to a non-returning function).  */
2683 
2684 bool
2685 is_ctrl_altering_stmt (gimple *t)
2686 {
2687   gcc_assert (t);
2688 
2689   switch (gimple_code (t))
2690     {
2691     case GIMPLE_CALL:
2692       /* Per stmt call flag indicates whether the call could alter
2693 	 controlflow.  */
2694       if (gimple_call_ctrl_altering_p (t))
2695 	return true;
2696       break;
2697 
2698     case GIMPLE_EH_DISPATCH:
2699       /* EH_DISPATCH branches to the individual catch handlers at
2700 	 this level of a try or allowed-exceptions region.  It can
2701 	 fallthru to the next statement as well.  */
2702       return true;
2703 
2704     case GIMPLE_ASM:
2705       if (gimple_asm_nlabels (as_a <gasm *> (t)) > 0)
2706 	return true;
2707       break;
2708 
2709     CASE_GIMPLE_OMP:
2710       /* OpenMP directives alter control flow.  */
2711       return true;
2712 
2713     case GIMPLE_TRANSACTION:
2714       /* A transaction start alters control flow.  */
2715       return true;
2716 
2717     default:
2718       break;
2719     }
2720 
2721   /* If a statement can throw, it alters control flow.  */
2722   return stmt_can_throw_internal (t);
2723 }
2724 
2725 
2726 /* Return true if T is a simple local goto.  */
2727 
2728 bool
2729 simple_goto_p (gimple *t)
2730 {
2731   return (gimple_code (t) == GIMPLE_GOTO
2732 	  && TREE_CODE (gimple_goto_dest (t)) == LABEL_DECL);
2733 }
2734 
2735 
2736 /* Return true if STMT should start a new basic block.  PREV_STMT is
2737    the statement preceding STMT.  It is used when STMT is a label or a
2738    case label.  Labels should only start a new basic block if their
2739    previous statement wasn't a label.  Otherwise, sequence of labels
2740    would generate unnecessary basic blocks that only contain a single
2741    label.  */
2742 
2743 static inline bool
2744 stmt_starts_bb_p (gimple *stmt, gimple *prev_stmt)
2745 {
2746   if (stmt == NULL)
2747     return false;
2748 
2749   /* PREV_STMT is only set to a debug stmt if the debug stmt is before
2750      any nondebug stmts in the block.  We don't want to start another
2751      block in this case: the debug stmt will already have started the
2752      one STMT would start if we weren't outputting debug stmts.  */
2753   if (prev_stmt && is_gimple_debug (prev_stmt))
2754     return false;
2755 
2756   /* Labels start a new basic block only if the preceding statement
2757      wasn't a label of the same type.  This prevents the creation of
2758      consecutive blocks that have nothing but a single label.  */
2759   if (glabel *label_stmt = dyn_cast <glabel *> (stmt))
2760     {
2761       /* Nonlocal and computed GOTO targets always start a new block.  */
2762       if (DECL_NONLOCAL (gimple_label_label (label_stmt))
2763 	  || FORCED_LABEL (gimple_label_label (label_stmt)))
2764 	return true;
2765 
2766       if (prev_stmt && gimple_code (prev_stmt) == GIMPLE_LABEL)
2767 	{
2768 	  if (DECL_NONLOCAL (gimple_label_label (
2769 			       as_a <glabel *> (prev_stmt))))
2770 	    return true;
2771 
2772 	  cfg_stats.num_merged_labels++;
2773 	  return false;
2774 	}
2775       else
2776 	return true;
2777     }
2778   else if (gimple_code (stmt) == GIMPLE_CALL)
2779     {
2780       if (gimple_call_flags (stmt) & ECF_RETURNS_TWICE)
2781 	/* setjmp acts similar to a nonlocal GOTO target and thus should
2782 	   start a new block.  */
2783 	return true;
2784       if (gimple_call_internal_p (stmt, IFN_PHI)
2785 	  && prev_stmt
2786 	  && gimple_code (prev_stmt) != GIMPLE_LABEL
2787 	  && (gimple_code (prev_stmt) != GIMPLE_CALL
2788 	      || ! gimple_call_internal_p (prev_stmt, IFN_PHI)))
2789 	/* PHI nodes start a new block unless preceeded by a label
2790 	   or another PHI.  */
2791 	return true;
2792     }
2793 
2794   return false;
2795 }
2796 
2797 
2798 /* Return true if T should end a basic block.  */
2799 
2800 bool
2801 stmt_ends_bb_p (gimple *t)
2802 {
2803   return is_ctrl_stmt (t) || is_ctrl_altering_stmt (t);
2804 }
2805 
2806 /* Remove block annotations and other data structures.  */
2807 
2808 void
2809 delete_tree_cfg_annotations (struct function *fn)
2810 {
2811   vec_free (label_to_block_map_for_fn (fn));
2812 }
2813 
2814 /* Return the virtual phi in BB.  */
2815 
2816 gphi *
2817 get_virtual_phi (basic_block bb)
2818 {
2819   for (gphi_iterator gsi = gsi_start_phis (bb);
2820        !gsi_end_p (gsi);
2821        gsi_next (&gsi))
2822     {
2823       gphi *phi = gsi.phi ();
2824 
2825       if (virtual_operand_p (PHI_RESULT (phi)))
2826 	return phi;
2827     }
2828 
2829   return NULL;
2830 }
2831 
2832 /* Return the first statement in basic block BB.  */
2833 
2834 gimple *
2835 first_stmt (basic_block bb)
2836 {
2837   gimple_stmt_iterator i = gsi_start_bb (bb);
2838   gimple *stmt = NULL;
2839 
2840   while (!gsi_end_p (i) && is_gimple_debug ((stmt = gsi_stmt (i))))
2841     {
2842       gsi_next (&i);
2843       stmt = NULL;
2844     }
2845   return stmt;
2846 }
2847 
2848 /* Return the first non-label statement in basic block BB.  */
2849 
2850 static gimple *
2851 first_non_label_stmt (basic_block bb)
2852 {
2853   gimple_stmt_iterator i = gsi_start_bb (bb);
2854   while (!gsi_end_p (i) && gimple_code (gsi_stmt (i)) == GIMPLE_LABEL)
2855     gsi_next (&i);
2856   return !gsi_end_p (i) ? gsi_stmt (i) : NULL;
2857 }
2858 
2859 /* Return the last statement in basic block BB.  */
2860 
2861 gimple *
2862 last_stmt (basic_block bb)
2863 {
2864   gimple_stmt_iterator i = gsi_last_bb (bb);
2865   gimple *stmt = NULL;
2866 
2867   while (!gsi_end_p (i) && is_gimple_debug ((stmt = gsi_stmt (i))))
2868     {
2869       gsi_prev (&i);
2870       stmt = NULL;
2871     }
2872   return stmt;
2873 }
2874 
2875 /* Return the last statement of an otherwise empty block.  Return NULL
2876    if the block is totally empty, or if it contains more than one
2877    statement.  */
2878 
2879 gimple *
2880 last_and_only_stmt (basic_block bb)
2881 {
2882   gimple_stmt_iterator i = gsi_last_nondebug_bb (bb);
2883   gimple *last, *prev;
2884 
2885   if (gsi_end_p (i))
2886     return NULL;
2887 
2888   last = gsi_stmt (i);
2889   gsi_prev_nondebug (&i);
2890   if (gsi_end_p (i))
2891     return last;
2892 
2893   /* Empty statements should no longer appear in the instruction stream.
2894      Everything that might have appeared before should be deleted by
2895      remove_useless_stmts, and the optimizers should just gsi_remove
2896      instead of smashing with build_empty_stmt.
2897 
2898      Thus the only thing that should appear here in a block containing
2899      one executable statement is a label.  */
2900   prev = gsi_stmt (i);
2901   if (gimple_code (prev) == GIMPLE_LABEL)
2902     return last;
2903   else
2904     return NULL;
2905 }
2906 
2907 /* Reinstall those PHI arguments queued in OLD_EDGE to NEW_EDGE.  */
2908 
2909 static void
2910 reinstall_phi_args (edge new_edge, edge old_edge)
2911 {
2912   edge_var_map *vm;
2913   int i;
2914   gphi_iterator phis;
2915 
2916   vec<edge_var_map> *v = redirect_edge_var_map_vector (old_edge);
2917   if (!v)
2918     return;
2919 
2920   for (i = 0, phis = gsi_start_phis (new_edge->dest);
2921        v->iterate (i, &vm) && !gsi_end_p (phis);
2922        i++, gsi_next (&phis))
2923     {
2924       gphi *phi = phis.phi ();
2925       tree result = redirect_edge_var_map_result (vm);
2926       tree arg = redirect_edge_var_map_def (vm);
2927 
2928       gcc_assert (result == gimple_phi_result (phi));
2929 
2930       add_phi_arg (phi, arg, new_edge, redirect_edge_var_map_location (vm));
2931     }
2932 
2933   redirect_edge_var_map_clear (old_edge);
2934 }
2935 
2936 /* Returns the basic block after which the new basic block created
2937    by splitting edge EDGE_IN should be placed.  Tries to keep the new block
2938    near its "logical" location.  This is of most help to humans looking
2939    at debugging dumps.  */
2940 
2941 basic_block
2942 split_edge_bb_loc (edge edge_in)
2943 {
2944   basic_block dest = edge_in->dest;
2945   basic_block dest_prev = dest->prev_bb;
2946 
2947   if (dest_prev)
2948     {
2949       edge e = find_edge (dest_prev, dest);
2950       if (e && !(e->flags & EDGE_COMPLEX))
2951 	return edge_in->src;
2952     }
2953   return dest_prev;
2954 }
2955 
2956 /* Split a (typically critical) edge EDGE_IN.  Return the new block.
2957    Abort on abnormal edges.  */
2958 
2959 static basic_block
2960 gimple_split_edge (edge edge_in)
2961 {
2962   basic_block new_bb, after_bb, dest;
2963   edge new_edge, e;
2964 
2965   /* Abnormal edges cannot be split.  */
2966   gcc_assert (!(edge_in->flags & EDGE_ABNORMAL));
2967 
2968   dest = edge_in->dest;
2969 
2970   after_bb = split_edge_bb_loc (edge_in);
2971 
2972   new_bb = create_empty_bb (after_bb);
2973   new_bb->count = edge_in->count ();
2974 
2975   e = redirect_edge_and_branch (edge_in, new_bb);
2976   gcc_assert (e == edge_in);
2977 
2978   new_edge = make_single_succ_edge (new_bb, dest, EDGE_FALLTHRU);
2979   reinstall_phi_args (new_edge, e);
2980 
2981   return new_bb;
2982 }
2983 
2984 
2985 /* Verify properties of the address expression T with base object BASE.  */
2986 
2987 static tree
2988 verify_address (tree t, tree base)
2989 {
2990   bool old_constant;
2991   bool old_side_effects;
2992   bool new_constant;
2993   bool new_side_effects;
2994 
2995   old_constant = TREE_CONSTANT (t);
2996   old_side_effects = TREE_SIDE_EFFECTS (t);
2997 
2998   recompute_tree_invariant_for_addr_expr (t);
2999   new_side_effects = TREE_SIDE_EFFECTS (t);
3000   new_constant = TREE_CONSTANT (t);
3001 
3002   if (old_constant != new_constant)
3003     {
3004       error ("constant not recomputed when ADDR_EXPR changed");
3005       return t;
3006     }
3007   if (old_side_effects != new_side_effects)
3008     {
3009       error ("side effects not recomputed when ADDR_EXPR changed");
3010       return t;
3011     }
3012 
3013   if (!(VAR_P (base)
3014 	|| TREE_CODE (base) == PARM_DECL
3015 	|| TREE_CODE (base) == RESULT_DECL))
3016     return NULL_TREE;
3017 
3018   if (DECL_GIMPLE_REG_P (base))
3019     {
3020       error ("DECL_GIMPLE_REG_P set on a variable with address taken");
3021       return base;
3022     }
3023 
3024   return NULL_TREE;
3025 }
3026 
3027 /* Callback for walk_tree, check that all elements with address taken are
3028    properly noticed as such.  The DATA is an int* that is 1 if TP was seen
3029    inside a PHI node.  */
3030 
3031 static tree
3032 verify_expr (tree *tp, int *walk_subtrees, void *data ATTRIBUTE_UNUSED)
3033 {
3034   tree t = *tp, x;
3035 
3036   if (TYPE_P (t))
3037     *walk_subtrees = 0;
3038 
3039   /* Check operand N for being valid GIMPLE and give error MSG if not.  */
3040 #define CHECK_OP(N, MSG) \
3041   do { if (!is_gimple_val (TREE_OPERAND (t, N)))		\
3042        { error (MSG); return TREE_OPERAND (t, N); }} while (0)
3043 
3044   switch (TREE_CODE (t))
3045     {
3046     case SSA_NAME:
3047       if (SSA_NAME_IN_FREE_LIST (t))
3048 	{
3049 	  error ("SSA name in freelist but still referenced");
3050 	  return *tp;
3051 	}
3052       break;
3053 
3054     case PARM_DECL:
3055     case VAR_DECL:
3056     case RESULT_DECL:
3057       {
3058 	tree context = decl_function_context (t);
3059 	if (context != cfun->decl
3060 	    && !SCOPE_FILE_SCOPE_P (context)
3061 	    && !TREE_STATIC (t)
3062 	    && !DECL_EXTERNAL (t))
3063 	  {
3064 	    error ("Local declaration from a different function");
3065 	    return t;
3066 	  }
3067       }
3068       break;
3069 
3070     case INDIRECT_REF:
3071       error ("INDIRECT_REF in gimple IL");
3072       return t;
3073 
3074     case MEM_REF:
3075       x = TREE_OPERAND (t, 0);
3076       if (!POINTER_TYPE_P (TREE_TYPE (x))
3077 	  || !is_gimple_mem_ref_addr (x))
3078 	{
3079 	  error ("invalid first operand of MEM_REF");
3080 	  return x;
3081 	}
3082       if (!poly_int_tree_p (TREE_OPERAND (t, 1))
3083 	  || !POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 1))))
3084 	{
3085 	  error ("invalid offset operand of MEM_REF");
3086 	  return TREE_OPERAND (t, 1);
3087 	}
3088       if (TREE_CODE (x) == ADDR_EXPR)
3089 	{
3090 	  tree va = verify_address (x, TREE_OPERAND (x, 0));
3091 	  if (va)
3092 	    return va;
3093 	  x = TREE_OPERAND (x, 0);
3094 	}
3095       walk_tree (&x, verify_expr, data, NULL);
3096       *walk_subtrees = 0;
3097       break;
3098 
3099     case ASSERT_EXPR:
3100       x = fold (ASSERT_EXPR_COND (t));
3101       if (x == boolean_false_node)
3102 	{
3103 	  error ("ASSERT_EXPR with an always-false condition");
3104 	  return *tp;
3105 	}
3106       break;
3107 
3108     case MODIFY_EXPR:
3109       error ("MODIFY_EXPR not expected while having tuples");
3110       return *tp;
3111 
3112     case ADDR_EXPR:
3113       {
3114 	tree tem;
3115 
3116 	gcc_assert (is_gimple_address (t));
3117 
3118 	/* Skip any references (they will be checked when we recurse down the
3119 	   tree) and ensure that any variable used as a prefix is marked
3120 	   addressable.  */
3121 	for (x = TREE_OPERAND (t, 0);
3122 	     handled_component_p (x);
3123 	     x = TREE_OPERAND (x, 0))
3124 	  ;
3125 
3126 	if ((tem = verify_address (t, x)))
3127 	  return tem;
3128 
3129 	if (!(VAR_P (x)
3130 	      || TREE_CODE (x) == PARM_DECL
3131 	      || TREE_CODE (x) == RESULT_DECL))
3132 	  return NULL;
3133 
3134 	if (!TREE_ADDRESSABLE (x))
3135 	  {
3136 	    error ("address taken, but ADDRESSABLE bit not set");
3137 	    return x;
3138 	  }
3139 
3140 	break;
3141       }
3142 
3143     case COND_EXPR:
3144       x = COND_EXPR_COND (t);
3145       if (!INTEGRAL_TYPE_P (TREE_TYPE (x)))
3146 	{
3147 	  error ("non-integral used in condition");
3148 	  return x;
3149 	}
3150       if (!is_gimple_condexpr (x))
3151         {
3152 	  error ("invalid conditional operand");
3153 	  return x;
3154 	}
3155       break;
3156 
3157     case NON_LVALUE_EXPR:
3158     case TRUTH_NOT_EXPR:
3159       gcc_unreachable ();
3160 
3161     CASE_CONVERT:
3162     case FIX_TRUNC_EXPR:
3163     case FLOAT_EXPR:
3164     case NEGATE_EXPR:
3165     case ABS_EXPR:
3166     case BIT_NOT_EXPR:
3167       CHECK_OP (0, "invalid operand to unary operator");
3168       break;
3169 
3170     case REALPART_EXPR:
3171     case IMAGPART_EXPR:
3172     case BIT_FIELD_REF:
3173       if (!is_gimple_reg_type (TREE_TYPE (t)))
3174 	{
3175 	  error ("non-scalar BIT_FIELD_REF, IMAGPART_EXPR or REALPART_EXPR");
3176 	  return t;
3177 	}
3178 
3179       if (TREE_CODE (t) == BIT_FIELD_REF)
3180 	{
3181 	  tree t0 = TREE_OPERAND (t, 0);
3182 	  tree t1 = TREE_OPERAND (t, 1);
3183 	  tree t2 = TREE_OPERAND (t, 2);
3184 	  poly_uint64 size, bitpos;
3185 	  if (!poly_int_tree_p (t1, &size)
3186 	      || !poly_int_tree_p (t2, &bitpos)
3187 	      || !types_compatible_p (bitsizetype, TREE_TYPE (t1))
3188 	      || !types_compatible_p (bitsizetype, TREE_TYPE (t2)))
3189 	    {
3190 	      error ("invalid position or size operand to BIT_FIELD_REF");
3191 	      return t;
3192 	    }
3193 	  if (INTEGRAL_TYPE_P (TREE_TYPE (t))
3194 	      && maybe_ne (TYPE_PRECISION (TREE_TYPE (t)), size))
3195 	    {
3196 	      error ("integral result type precision does not match "
3197 		     "field size of BIT_FIELD_REF");
3198 	      return t;
3199 	    }
3200 	  else if (!INTEGRAL_TYPE_P (TREE_TYPE (t))
3201 		   && TYPE_MODE (TREE_TYPE (t)) != BLKmode
3202 		   && maybe_ne (GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (t))),
3203 				size))
3204 	    {
3205 	      error ("mode size of non-integral result does not "
3206 		     "match field size of BIT_FIELD_REF");
3207 	      return t;
3208 	    }
3209 	  if (!AGGREGATE_TYPE_P (TREE_TYPE (t0))
3210 	      && maybe_gt (size + bitpos,
3211 			   tree_to_poly_uint64 (TYPE_SIZE (TREE_TYPE (t0)))))
3212 	    {
3213 	      error ("position plus size exceeds size of referenced object in "
3214 		     "BIT_FIELD_REF");
3215 	      return t;
3216 	    }
3217 	}
3218       t = TREE_OPERAND (t, 0);
3219 
3220       /* Fall-through.  */
3221     case COMPONENT_REF:
3222     case ARRAY_REF:
3223     case ARRAY_RANGE_REF:
3224     case VIEW_CONVERT_EXPR:
3225       /* We have a nest of references.  Verify that each of the operands
3226 	 that determine where to reference is either a constant or a variable,
3227 	 verify that the base is valid, and then show we've already checked
3228 	 the subtrees.  */
3229       while (handled_component_p (t))
3230 	{
3231 	  if (TREE_CODE (t) == COMPONENT_REF && TREE_OPERAND (t, 2))
3232 	    CHECK_OP (2, "invalid COMPONENT_REF offset operator");
3233 	  else if (TREE_CODE (t) == ARRAY_REF
3234 		   || TREE_CODE (t) == ARRAY_RANGE_REF)
3235 	    {
3236 	      CHECK_OP (1, "invalid array index");
3237 	      if (TREE_OPERAND (t, 2))
3238 		CHECK_OP (2, "invalid array lower bound");
3239 	      if (TREE_OPERAND (t, 3))
3240 		CHECK_OP (3, "invalid array stride");
3241 	    }
3242 	  else if (TREE_CODE (t) == BIT_FIELD_REF
3243 		   || TREE_CODE (t) == REALPART_EXPR
3244 		   || TREE_CODE (t) == IMAGPART_EXPR)
3245 	    {
3246 	      error ("non-top-level BIT_FIELD_REF, IMAGPART_EXPR or "
3247 		     "REALPART_EXPR");
3248 	      return t;
3249 	    }
3250 
3251 	  t = TREE_OPERAND (t, 0);
3252 	}
3253 
3254       if (!is_gimple_min_invariant (t) && !is_gimple_lvalue (t))
3255 	{
3256 	  error ("invalid reference prefix");
3257 	  return t;
3258 	}
3259       walk_tree (&t, verify_expr, data, NULL);
3260       *walk_subtrees = 0;
3261       break;
3262     case PLUS_EXPR:
3263     case MINUS_EXPR:
3264       /* PLUS_EXPR and MINUS_EXPR don't work on pointers, they should be done using
3265 	 POINTER_PLUS_EXPR. */
3266       if (POINTER_TYPE_P (TREE_TYPE (t)))
3267 	{
3268 	  error ("invalid operand to plus/minus, type is a pointer");
3269 	  return t;
3270 	}
3271       CHECK_OP (0, "invalid operand to binary operator");
3272       CHECK_OP (1, "invalid operand to binary operator");
3273       break;
3274 
3275     case POINTER_DIFF_EXPR:
3276       if (!POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 0)))
3277 	  || !POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 1))))
3278 	{
3279 	  error ("invalid operand to pointer diff, operand is not a pointer");
3280 	  return t;
3281 	}
3282       if (TREE_CODE (TREE_TYPE (t)) != INTEGER_TYPE
3283 	  || TYPE_UNSIGNED (TREE_TYPE (t))
3284 	  || (TYPE_PRECISION (TREE_TYPE (t))
3285 	      != TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (t, 0)))))
3286 	{
3287 	  error ("invalid type for pointer diff");
3288 	  return t;
3289 	}
3290       CHECK_OP (0, "invalid operand to pointer diff");
3291       CHECK_OP (1, "invalid operand to pointer diff");
3292       break;
3293 
3294     case POINTER_PLUS_EXPR:
3295       /* Check to make sure the first operand is a pointer or reference type. */
3296       if (!POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (t, 0))))
3297 	{
3298 	  error ("invalid operand to pointer plus, first operand is not a pointer");
3299 	  return t;
3300 	}
3301       /* Check to make sure the second operand is a ptrofftype.  */
3302       if (!ptrofftype_p (TREE_TYPE (TREE_OPERAND (t, 1))))
3303 	{
3304 	  error ("invalid operand to pointer plus, second operand is not an "
3305 		 "integer type of appropriate width");
3306 	  return t;
3307 	}
3308       /* FALLTHROUGH */
3309     case LT_EXPR:
3310     case LE_EXPR:
3311     case GT_EXPR:
3312     case GE_EXPR:
3313     case EQ_EXPR:
3314     case NE_EXPR:
3315     case UNORDERED_EXPR:
3316     case ORDERED_EXPR:
3317     case UNLT_EXPR:
3318     case UNLE_EXPR:
3319     case UNGT_EXPR:
3320     case UNGE_EXPR:
3321     case UNEQ_EXPR:
3322     case LTGT_EXPR:
3323     case MULT_EXPR:
3324     case TRUNC_DIV_EXPR:
3325     case CEIL_DIV_EXPR:
3326     case FLOOR_DIV_EXPR:
3327     case ROUND_DIV_EXPR:
3328     case TRUNC_MOD_EXPR:
3329     case CEIL_MOD_EXPR:
3330     case FLOOR_MOD_EXPR:
3331     case ROUND_MOD_EXPR:
3332     case RDIV_EXPR:
3333     case EXACT_DIV_EXPR:
3334     case MIN_EXPR:
3335     case MAX_EXPR:
3336     case LSHIFT_EXPR:
3337     case RSHIFT_EXPR:
3338     case LROTATE_EXPR:
3339     case RROTATE_EXPR:
3340     case BIT_IOR_EXPR:
3341     case BIT_XOR_EXPR:
3342     case BIT_AND_EXPR:
3343       CHECK_OP (0, "invalid operand to binary operator");
3344       CHECK_OP (1, "invalid operand to binary operator");
3345       break;
3346 
3347     case CONSTRUCTOR:
3348       if (TREE_CONSTANT (t) && TREE_CODE (TREE_TYPE (t)) == VECTOR_TYPE)
3349 	*walk_subtrees = 0;
3350       break;
3351 
3352     case CASE_LABEL_EXPR:
3353       if (CASE_CHAIN (t))
3354 	{
3355 	  error ("invalid CASE_CHAIN");
3356 	  return t;
3357 	}
3358       break;
3359 
3360     default:
3361       break;
3362     }
3363   return NULL;
3364 
3365 #undef CHECK_OP
3366 }
3367 
3368 
3369 /* Verify if EXPR is either a GIMPLE ID or a GIMPLE indirect reference.
3370    Returns true if there is an error, otherwise false.  */
3371 
3372 static bool
3373 verify_types_in_gimple_min_lval (tree expr)
3374 {
3375   tree op;
3376 
3377   if (is_gimple_id (expr))
3378     return false;
3379 
3380   if (TREE_CODE (expr) != TARGET_MEM_REF
3381       && TREE_CODE (expr) != MEM_REF)
3382     {
3383       error ("invalid expression for min lvalue");
3384       return true;
3385     }
3386 
3387   /* TARGET_MEM_REFs are strange beasts.  */
3388   if (TREE_CODE (expr) == TARGET_MEM_REF)
3389     return false;
3390 
3391   op = TREE_OPERAND (expr, 0);
3392   if (!is_gimple_val (op))
3393     {
3394       error ("invalid operand in indirect reference");
3395       debug_generic_stmt (op);
3396       return true;
3397     }
3398   /* Memory references now generally can involve a value conversion.  */
3399 
3400   return false;
3401 }
3402 
3403 /* Verify if EXPR is a valid GIMPLE reference expression.  If
3404    REQUIRE_LVALUE is true verifies it is an lvalue.  Returns true
3405    if there is an error, otherwise false.  */
3406 
3407 static bool
3408 verify_types_in_gimple_reference (tree expr, bool require_lvalue)
3409 {
3410   while (handled_component_p (expr))
3411     {
3412       tree op = TREE_OPERAND (expr, 0);
3413 
3414       if (TREE_CODE (expr) == ARRAY_REF
3415 	  || TREE_CODE (expr) == ARRAY_RANGE_REF)
3416 	{
3417 	  if (!is_gimple_val (TREE_OPERAND (expr, 1))
3418 	      || (TREE_OPERAND (expr, 2)
3419 		  && !is_gimple_val (TREE_OPERAND (expr, 2)))
3420 	      || (TREE_OPERAND (expr, 3)
3421 		  && !is_gimple_val (TREE_OPERAND (expr, 3))))
3422 	    {
3423 	      error ("invalid operands to array reference");
3424 	      debug_generic_stmt (expr);
3425 	      return true;
3426 	    }
3427 	}
3428 
3429       /* Verify if the reference array element types are compatible.  */
3430       if (TREE_CODE (expr) == ARRAY_REF
3431 	  && !useless_type_conversion_p (TREE_TYPE (expr),
3432 					 TREE_TYPE (TREE_TYPE (op))))
3433 	{
3434 	  error ("type mismatch in array reference");
3435 	  debug_generic_stmt (TREE_TYPE (expr));
3436 	  debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3437 	  return true;
3438 	}
3439       if (TREE_CODE (expr) == ARRAY_RANGE_REF
3440 	  && !useless_type_conversion_p (TREE_TYPE (TREE_TYPE (expr)),
3441 					 TREE_TYPE (TREE_TYPE (op))))
3442 	{
3443 	  error ("type mismatch in array range reference");
3444 	  debug_generic_stmt (TREE_TYPE (TREE_TYPE (expr)));
3445 	  debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3446 	  return true;
3447 	}
3448 
3449       if ((TREE_CODE (expr) == REALPART_EXPR
3450 	   || TREE_CODE (expr) == IMAGPART_EXPR)
3451 	  && !useless_type_conversion_p (TREE_TYPE (expr),
3452 					 TREE_TYPE (TREE_TYPE (op))))
3453 	{
3454 	  error ("type mismatch in real/imagpart reference");
3455 	  debug_generic_stmt (TREE_TYPE (expr));
3456 	  debug_generic_stmt (TREE_TYPE (TREE_TYPE (op)));
3457 	  return true;
3458 	}
3459 
3460       if (TREE_CODE (expr) == COMPONENT_REF
3461 	  && !useless_type_conversion_p (TREE_TYPE (expr),
3462 					 TREE_TYPE (TREE_OPERAND (expr, 1))))
3463 	{
3464 	  error ("type mismatch in component reference");
3465 	  debug_generic_stmt (TREE_TYPE (expr));
3466 	  debug_generic_stmt (TREE_TYPE (TREE_OPERAND (expr, 1)));
3467 	  return true;
3468 	}
3469 
3470       if (TREE_CODE (expr) == VIEW_CONVERT_EXPR)
3471 	{
3472 	  /* For VIEW_CONVERT_EXPRs which are allowed here too, we only check
3473 	     that their operand is not an SSA name or an invariant when
3474 	     requiring an lvalue (this usually means there is a SRA or IPA-SRA
3475 	     bug).  Otherwise there is nothing to verify, gross mismatches at
3476 	     most invoke undefined behavior.  */
3477 	  if (require_lvalue
3478 	      && (TREE_CODE (op) == SSA_NAME
3479 		  || is_gimple_min_invariant (op)))
3480 	    {
3481 	      error ("conversion of an SSA_NAME on the left hand side");
3482 	      debug_generic_stmt (expr);
3483 	      return true;
3484 	    }
3485 	  else if (TREE_CODE (op) == SSA_NAME
3486 		   && TYPE_SIZE (TREE_TYPE (expr)) != TYPE_SIZE (TREE_TYPE (op)))
3487 	    {
3488 	      error ("conversion of register to a different size");
3489 	      debug_generic_stmt (expr);
3490 	      return true;
3491 	    }
3492 	  else if (!handled_component_p (op))
3493 	    return false;
3494 	}
3495 
3496       expr = op;
3497     }
3498 
3499   if (TREE_CODE (expr) == MEM_REF)
3500     {
3501       if (!is_gimple_mem_ref_addr (TREE_OPERAND (expr, 0)))
3502 	{
3503 	  error ("invalid address operand in MEM_REF");
3504 	  debug_generic_stmt (expr);
3505 	  return true;
3506 	}
3507       if (!poly_int_tree_p (TREE_OPERAND (expr, 1))
3508 	  || !POINTER_TYPE_P (TREE_TYPE (TREE_OPERAND (expr, 1))))
3509 	{
3510 	  error ("invalid offset operand in MEM_REF");
3511 	  debug_generic_stmt (expr);
3512 	  return true;
3513 	}
3514     }
3515   else if (TREE_CODE (expr) == TARGET_MEM_REF)
3516     {
3517       if (!TMR_BASE (expr)
3518 	  || !is_gimple_mem_ref_addr (TMR_BASE (expr)))
3519 	{
3520 	  error ("invalid address operand in TARGET_MEM_REF");
3521 	  return true;
3522 	}
3523       if (!TMR_OFFSET (expr)
3524 	  || !poly_int_tree_p (TMR_OFFSET (expr))
3525 	  || !POINTER_TYPE_P (TREE_TYPE (TMR_OFFSET (expr))))
3526 	{
3527 	  error ("invalid offset operand in TARGET_MEM_REF");
3528 	  debug_generic_stmt (expr);
3529 	  return true;
3530 	}
3531     }
3532 
3533   return ((require_lvalue || !is_gimple_min_invariant (expr))
3534 	  && verify_types_in_gimple_min_lval (expr));
3535 }
3536 
3537 /* Returns true if there is one pointer type in TYPE_POINTER_TO (SRC_OBJ)
3538    list of pointer-to types that is trivially convertible to DEST.  */
3539 
3540 static bool
3541 one_pointer_to_useless_type_conversion_p (tree dest, tree src_obj)
3542 {
3543   tree src;
3544 
3545   if (!TYPE_POINTER_TO (src_obj))
3546     return true;
3547 
3548   for (src = TYPE_POINTER_TO (src_obj); src; src = TYPE_NEXT_PTR_TO (src))
3549     if (useless_type_conversion_p (dest, src))
3550       return true;
3551 
3552   return false;
3553 }
3554 
3555 /* Return true if TYPE1 is a fixed-point type and if conversions to and
3556    from TYPE2 can be handled by FIXED_CONVERT_EXPR.  */
3557 
3558 static bool
3559 valid_fixed_convert_types_p (tree type1, tree type2)
3560 {
3561   return (FIXED_POINT_TYPE_P (type1)
3562 	  && (INTEGRAL_TYPE_P (type2)
3563 	      || SCALAR_FLOAT_TYPE_P (type2)
3564 	      || FIXED_POINT_TYPE_P (type2)));
3565 }
3566 
3567 /* Verify the contents of a GIMPLE_CALL STMT.  Returns true when there
3568    is a problem, otherwise false.  */
3569 
3570 static bool
3571 verify_gimple_call (gcall *stmt)
3572 {
3573   tree fn = gimple_call_fn (stmt);
3574   tree fntype, fndecl;
3575   unsigned i;
3576 
3577   if (gimple_call_internal_p (stmt))
3578     {
3579       if (fn)
3580 	{
3581 	  error ("gimple call has two targets");
3582 	  debug_generic_stmt (fn);
3583 	  return true;
3584 	}
3585       /* FIXME : for passing label as arg in internal fn PHI from GIMPLE FE*/
3586       else if (gimple_call_internal_fn (stmt) == IFN_PHI)
3587 	{
3588 	  return false;
3589 	}
3590     }
3591   else
3592     {
3593       if (!fn)
3594 	{
3595 	  error ("gimple call has no target");
3596 	  return true;
3597 	}
3598     }
3599 
3600   if (fn && !is_gimple_call_addr (fn))
3601     {
3602       error ("invalid function in gimple call");
3603       debug_generic_stmt (fn);
3604       return true;
3605     }
3606 
3607   if (fn
3608       && (!POINTER_TYPE_P (TREE_TYPE (fn))
3609 	  || (TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != FUNCTION_TYPE
3610 	      && TREE_CODE (TREE_TYPE (TREE_TYPE (fn))) != METHOD_TYPE)))
3611     {
3612       error ("non-function in gimple call");
3613       return true;
3614     }
3615 
3616    fndecl = gimple_call_fndecl (stmt);
3617    if (fndecl
3618        && TREE_CODE (fndecl) == FUNCTION_DECL
3619        && DECL_LOOPING_CONST_OR_PURE_P (fndecl)
3620        && !DECL_PURE_P (fndecl)
3621        && !TREE_READONLY (fndecl))
3622      {
3623        error ("invalid pure const state for function");
3624        return true;
3625      }
3626 
3627   tree lhs = gimple_call_lhs (stmt);
3628   if (lhs
3629       && (!is_gimple_lvalue (lhs)
3630 	  || verify_types_in_gimple_reference (lhs, true)))
3631     {
3632       error ("invalid LHS in gimple call");
3633       return true;
3634     }
3635 
3636   if (gimple_call_ctrl_altering_p (stmt)
3637       && gimple_call_noreturn_p (stmt)
3638       && should_remove_lhs_p (lhs))
3639     {
3640       error ("LHS in noreturn call");
3641       return true;
3642     }
3643 
3644   fntype = gimple_call_fntype (stmt);
3645   if (fntype
3646       && lhs
3647       && !useless_type_conversion_p (TREE_TYPE (lhs), TREE_TYPE (fntype))
3648       /* ???  At least C++ misses conversions at assignments from
3649 	 void * call results.
3650 	 For now simply allow arbitrary pointer type conversions.  */
3651       && !(POINTER_TYPE_P (TREE_TYPE (lhs))
3652 	   && POINTER_TYPE_P (TREE_TYPE (fntype))))
3653     {
3654       error ("invalid conversion in gimple call");
3655       debug_generic_stmt (TREE_TYPE (lhs));
3656       debug_generic_stmt (TREE_TYPE (fntype));
3657       return true;
3658     }
3659 
3660   if (gimple_call_chain (stmt)
3661       && !is_gimple_val (gimple_call_chain (stmt)))
3662     {
3663       error ("invalid static chain in gimple call");
3664       debug_generic_stmt (gimple_call_chain (stmt));
3665       return true;
3666     }
3667 
3668   /* If there is a static chain argument, the call should either be
3669      indirect, or the decl should have DECL_STATIC_CHAIN set.  */
3670   if (gimple_call_chain (stmt)
3671       && fndecl
3672       && !DECL_STATIC_CHAIN (fndecl))
3673     {
3674       error ("static chain with function that doesn%'t use one");
3675       return true;
3676     }
3677 
3678   if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
3679     {
3680       switch (DECL_FUNCTION_CODE (fndecl))
3681 	{
3682 	case BUILT_IN_UNREACHABLE:
3683 	case BUILT_IN_TRAP:
3684 	  if (gimple_call_num_args (stmt) > 0)
3685 	    {
3686 	      /* Built-in unreachable with parameters might not be caught by
3687 		 undefined behavior sanitizer.  Front-ends do check users do not
3688 		 call them that way but we also produce calls to
3689 		 __builtin_unreachable internally, for example when IPA figures
3690 		 out a call cannot happen in a legal program.  In such cases,
3691 		 we must make sure arguments are stripped off.  */
3692 	      error ("__builtin_unreachable or __builtin_trap call with "
3693 		     "arguments");
3694 	      return true;
3695 	    }
3696 	  break;
3697 	default:
3698 	  break;
3699 	}
3700     }
3701 
3702   /* ???  The C frontend passes unpromoted arguments in case it
3703      didn't see a function declaration before the call.  So for now
3704      leave the call arguments mostly unverified.  Once we gimplify
3705      unit-at-a-time we have a chance to fix this.  */
3706 
3707   for (i = 0; i < gimple_call_num_args (stmt); ++i)
3708     {
3709       tree arg = gimple_call_arg (stmt, i);
3710       if ((is_gimple_reg_type (TREE_TYPE (arg))
3711 	   && !is_gimple_val (arg))
3712 	  || (!is_gimple_reg_type (TREE_TYPE (arg))
3713 	      && !is_gimple_lvalue (arg)))
3714 	{
3715 	  error ("invalid argument to gimple call");
3716 	  debug_generic_expr (arg);
3717 	  return true;
3718 	}
3719     }
3720 
3721   return false;
3722 }
3723 
3724 /* Verifies the gimple comparison with the result type TYPE and
3725    the operands OP0 and OP1, comparison code is CODE.  */
3726 
3727 static bool
3728 verify_gimple_comparison (tree type, tree op0, tree op1, enum tree_code code)
3729 {
3730   tree op0_type = TREE_TYPE (op0);
3731   tree op1_type = TREE_TYPE (op1);
3732 
3733   if (!is_gimple_val (op0) || !is_gimple_val (op1))
3734     {
3735       error ("invalid operands in gimple comparison");
3736       return true;
3737     }
3738 
3739   /* For comparisons we do not have the operations type as the
3740      effective type the comparison is carried out in.  Instead
3741      we require that either the first operand is trivially
3742      convertible into the second, or the other way around.
3743      Because we special-case pointers to void we allow
3744      comparisons of pointers with the same mode as well.  */
3745   if (!useless_type_conversion_p (op0_type, op1_type)
3746       && !useless_type_conversion_p (op1_type, op0_type)
3747       && (!POINTER_TYPE_P (op0_type)
3748 	  || !POINTER_TYPE_P (op1_type)
3749 	  || TYPE_MODE (op0_type) != TYPE_MODE (op1_type)))
3750     {
3751       error ("mismatching comparison operand types");
3752       debug_generic_expr (op0_type);
3753       debug_generic_expr (op1_type);
3754       return true;
3755     }
3756 
3757   /* The resulting type of a comparison may be an effective boolean type.  */
3758   if (INTEGRAL_TYPE_P (type)
3759       && (TREE_CODE (type) == BOOLEAN_TYPE
3760 	  || TYPE_PRECISION (type) == 1))
3761     {
3762       if ((TREE_CODE (op0_type) == VECTOR_TYPE
3763 	   || TREE_CODE (op1_type) == VECTOR_TYPE)
3764 	  && code != EQ_EXPR && code != NE_EXPR
3765 	  && !VECTOR_BOOLEAN_TYPE_P (op0_type)
3766 	  && !VECTOR_INTEGER_TYPE_P (op0_type))
3767 	{
3768 	  error ("unsupported operation or type for vector comparison"
3769 		 " returning a boolean");
3770 	  debug_generic_expr (op0_type);
3771 	  debug_generic_expr (op1_type);
3772 	  return true;
3773         }
3774     }
3775   /* Or a boolean vector type with the same element count
3776      as the comparison operand types.  */
3777   else if (TREE_CODE (type) == VECTOR_TYPE
3778 	   && TREE_CODE (TREE_TYPE (type)) == BOOLEAN_TYPE)
3779     {
3780       if (TREE_CODE (op0_type) != VECTOR_TYPE
3781 	  || TREE_CODE (op1_type) != VECTOR_TYPE)
3782         {
3783           error ("non-vector operands in vector comparison");
3784           debug_generic_expr (op0_type);
3785           debug_generic_expr (op1_type);
3786           return true;
3787         }
3788 
3789       if (maybe_ne (TYPE_VECTOR_SUBPARTS (type),
3790 		    TYPE_VECTOR_SUBPARTS (op0_type)))
3791         {
3792           error ("invalid vector comparison resulting type");
3793           debug_generic_expr (type);
3794           return true;
3795         }
3796     }
3797   else
3798     {
3799       error ("bogus comparison result type");
3800       debug_generic_expr (type);
3801       return true;
3802     }
3803 
3804   return false;
3805 }
3806 
3807 /* Verify a gimple assignment statement STMT with an unary rhs.
3808    Returns true if anything is wrong.  */
3809 
3810 static bool
3811 verify_gimple_assign_unary (gassign *stmt)
3812 {
3813   enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3814   tree lhs = gimple_assign_lhs (stmt);
3815   tree lhs_type = TREE_TYPE (lhs);
3816   tree rhs1 = gimple_assign_rhs1 (stmt);
3817   tree rhs1_type = TREE_TYPE (rhs1);
3818 
3819   if (!is_gimple_reg (lhs))
3820     {
3821       error ("non-register as LHS of unary operation");
3822       return true;
3823     }
3824 
3825   if (!is_gimple_val (rhs1))
3826     {
3827       error ("invalid operand in unary operation");
3828       return true;
3829     }
3830 
3831   /* First handle conversions.  */
3832   switch (rhs_code)
3833     {
3834     CASE_CONVERT:
3835       {
3836 	/* Allow conversions from pointer type to integral type only if
3837 	   there is no sign or zero extension involved.
3838 	   For targets were the precision of ptrofftype doesn't match that
3839 	   of pointers we need to allow arbitrary conversions to ptrofftype.  */
3840 	if ((POINTER_TYPE_P (lhs_type)
3841 	     && INTEGRAL_TYPE_P (rhs1_type))
3842 	    || (POINTER_TYPE_P (rhs1_type)
3843 		&& INTEGRAL_TYPE_P (lhs_type)
3844 		&& (TYPE_PRECISION (rhs1_type) >= TYPE_PRECISION (lhs_type)
3845 		    || ptrofftype_p (sizetype))))
3846 	  return false;
3847 
3848 	/* Allow conversion from integral to offset type and vice versa.  */
3849 	if ((TREE_CODE (lhs_type) == OFFSET_TYPE
3850 	     && INTEGRAL_TYPE_P (rhs1_type))
3851 	    || (INTEGRAL_TYPE_P (lhs_type)
3852 		&& TREE_CODE (rhs1_type) == OFFSET_TYPE))
3853 	  return false;
3854 
3855 	/* Otherwise assert we are converting between types of the
3856 	   same kind.  */
3857 	if (INTEGRAL_TYPE_P (lhs_type) != INTEGRAL_TYPE_P (rhs1_type))
3858 	  {
3859 	    error ("invalid types in nop conversion");
3860 	    debug_generic_expr (lhs_type);
3861 	    debug_generic_expr (rhs1_type);
3862 	    return true;
3863 	  }
3864 
3865 	return false;
3866       }
3867 
3868     case ADDR_SPACE_CONVERT_EXPR:
3869       {
3870 	if (!POINTER_TYPE_P (rhs1_type) || !POINTER_TYPE_P (lhs_type)
3871 	    || (TYPE_ADDR_SPACE (TREE_TYPE (rhs1_type))
3872 		== TYPE_ADDR_SPACE (TREE_TYPE (lhs_type))))
3873 	  {
3874 	    error ("invalid types in address space conversion");
3875 	    debug_generic_expr (lhs_type);
3876 	    debug_generic_expr (rhs1_type);
3877 	    return true;
3878 	  }
3879 
3880 	return false;
3881       }
3882 
3883     case FIXED_CONVERT_EXPR:
3884       {
3885 	if (!valid_fixed_convert_types_p (lhs_type, rhs1_type)
3886 	    && !valid_fixed_convert_types_p (rhs1_type, lhs_type))
3887 	  {
3888 	    error ("invalid types in fixed-point conversion");
3889 	    debug_generic_expr (lhs_type);
3890 	    debug_generic_expr (rhs1_type);
3891 	    return true;
3892 	  }
3893 
3894 	return false;
3895       }
3896 
3897     case FLOAT_EXPR:
3898       {
3899 	if ((!INTEGRAL_TYPE_P (rhs1_type) || !SCALAR_FLOAT_TYPE_P (lhs_type))
3900 	    && (!VECTOR_INTEGER_TYPE_P (rhs1_type)
3901 	        || !VECTOR_FLOAT_TYPE_P (lhs_type)))
3902 	  {
3903 	    error ("invalid types in conversion to floating point");
3904 	    debug_generic_expr (lhs_type);
3905 	    debug_generic_expr (rhs1_type);
3906 	    return true;
3907 	  }
3908 
3909         return false;
3910       }
3911 
3912     case FIX_TRUNC_EXPR:
3913       {
3914         if ((!INTEGRAL_TYPE_P (lhs_type) || !SCALAR_FLOAT_TYPE_P (rhs1_type))
3915             && (!VECTOR_INTEGER_TYPE_P (lhs_type)
3916                 || !VECTOR_FLOAT_TYPE_P (rhs1_type)))
3917 	  {
3918 	    error ("invalid types in conversion to integer");
3919 	    debug_generic_expr (lhs_type);
3920 	    debug_generic_expr (rhs1_type);
3921 	    return true;
3922 	  }
3923 
3924         return false;
3925       }
3926 
3927     case VEC_UNPACK_HI_EXPR:
3928     case VEC_UNPACK_LO_EXPR:
3929     case VEC_UNPACK_FLOAT_HI_EXPR:
3930     case VEC_UNPACK_FLOAT_LO_EXPR:
3931       /* FIXME.  */
3932       return false;
3933 
3934     case NEGATE_EXPR:
3935     case ABS_EXPR:
3936     case BIT_NOT_EXPR:
3937     case PAREN_EXPR:
3938     case CONJ_EXPR:
3939       break;
3940 
3941     case VEC_DUPLICATE_EXPR:
3942       if (TREE_CODE (lhs_type) != VECTOR_TYPE
3943 	  || !useless_type_conversion_p (TREE_TYPE (lhs_type), rhs1_type))
3944 	{
3945 	  error ("vec_duplicate should be from a scalar to a like vector");
3946 	  debug_generic_expr (lhs_type);
3947 	  debug_generic_expr (rhs1_type);
3948 	  return true;
3949 	}
3950       return false;
3951 
3952     default:
3953       gcc_unreachable ();
3954     }
3955 
3956   /* For the remaining codes assert there is no conversion involved.  */
3957   if (!useless_type_conversion_p (lhs_type, rhs1_type))
3958     {
3959       error ("non-trivial conversion in unary operation");
3960       debug_generic_expr (lhs_type);
3961       debug_generic_expr (rhs1_type);
3962       return true;
3963     }
3964 
3965   return false;
3966 }
3967 
3968 /* Verify a gimple assignment statement STMT with a binary rhs.
3969    Returns true if anything is wrong.  */
3970 
3971 static bool
3972 verify_gimple_assign_binary (gassign *stmt)
3973 {
3974   enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
3975   tree lhs = gimple_assign_lhs (stmt);
3976   tree lhs_type = TREE_TYPE (lhs);
3977   tree rhs1 = gimple_assign_rhs1 (stmt);
3978   tree rhs1_type = TREE_TYPE (rhs1);
3979   tree rhs2 = gimple_assign_rhs2 (stmt);
3980   tree rhs2_type = TREE_TYPE (rhs2);
3981 
3982   if (!is_gimple_reg (lhs))
3983     {
3984       error ("non-register as LHS of binary operation");
3985       return true;
3986     }
3987 
3988   if (!is_gimple_val (rhs1)
3989       || !is_gimple_val (rhs2))
3990     {
3991       error ("invalid operands in binary operation");
3992       return true;
3993     }
3994 
3995   /* First handle operations that involve different types.  */
3996   switch (rhs_code)
3997     {
3998     case COMPLEX_EXPR:
3999       {
4000 	if (TREE_CODE (lhs_type) != COMPLEX_TYPE
4001 	    || !(INTEGRAL_TYPE_P (rhs1_type)
4002 	         || SCALAR_FLOAT_TYPE_P (rhs1_type))
4003 	    || !(INTEGRAL_TYPE_P (rhs2_type)
4004 	         || SCALAR_FLOAT_TYPE_P (rhs2_type)))
4005 	  {
4006 	    error ("type mismatch in complex expression");
4007 	    debug_generic_expr (lhs_type);
4008 	    debug_generic_expr (rhs1_type);
4009 	    debug_generic_expr (rhs2_type);
4010 	    return true;
4011 	  }
4012 
4013 	return false;
4014       }
4015 
4016     case LSHIFT_EXPR:
4017     case RSHIFT_EXPR:
4018     case LROTATE_EXPR:
4019     case RROTATE_EXPR:
4020       {
4021 	/* Shifts and rotates are ok on integral types, fixed point
4022 	   types and integer vector types.  */
4023 	if ((!INTEGRAL_TYPE_P (rhs1_type)
4024 	     && !FIXED_POINT_TYPE_P (rhs1_type)
4025 	     && !(TREE_CODE (rhs1_type) == VECTOR_TYPE
4026 		  && INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))))
4027 	    || (!INTEGRAL_TYPE_P (rhs2_type)
4028 		/* Vector shifts of vectors are also ok.  */
4029 		&& !(TREE_CODE (rhs1_type) == VECTOR_TYPE
4030 		     && INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))
4031 		     && TREE_CODE (rhs2_type) == VECTOR_TYPE
4032 		     && INTEGRAL_TYPE_P (TREE_TYPE (rhs2_type))))
4033 	    || !useless_type_conversion_p (lhs_type, rhs1_type))
4034 	  {
4035 	    error ("type mismatch in shift expression");
4036 	    debug_generic_expr (lhs_type);
4037 	    debug_generic_expr (rhs1_type);
4038 	    debug_generic_expr (rhs2_type);
4039 	    return true;
4040 	  }
4041 
4042 	return false;
4043       }
4044 
4045     case WIDEN_LSHIFT_EXPR:
4046       {
4047         if (!INTEGRAL_TYPE_P (lhs_type)
4048             || !INTEGRAL_TYPE_P (rhs1_type)
4049             || TREE_CODE (rhs2) != INTEGER_CST
4050             || (2 * TYPE_PRECISION (rhs1_type) > TYPE_PRECISION (lhs_type)))
4051           {
4052             error ("type mismatch in widening vector shift expression");
4053             debug_generic_expr (lhs_type);
4054             debug_generic_expr (rhs1_type);
4055             debug_generic_expr (rhs2_type);
4056             return true;
4057           }
4058 
4059         return false;
4060       }
4061 
4062     case VEC_WIDEN_LSHIFT_HI_EXPR:
4063     case VEC_WIDEN_LSHIFT_LO_EXPR:
4064       {
4065         if (TREE_CODE (rhs1_type) != VECTOR_TYPE
4066             || TREE_CODE (lhs_type) != VECTOR_TYPE
4067             || !INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))
4068             || !INTEGRAL_TYPE_P (TREE_TYPE (lhs_type))
4069             || TREE_CODE (rhs2) != INTEGER_CST
4070             || (2 * TYPE_PRECISION (TREE_TYPE (rhs1_type))
4071                 > TYPE_PRECISION (TREE_TYPE (lhs_type))))
4072           {
4073             error ("type mismatch in widening vector shift expression");
4074             debug_generic_expr (lhs_type);
4075             debug_generic_expr (rhs1_type);
4076             debug_generic_expr (rhs2_type);
4077             return true;
4078           }
4079 
4080         return false;
4081       }
4082 
4083     case PLUS_EXPR:
4084     case MINUS_EXPR:
4085       {
4086 	tree lhs_etype = lhs_type;
4087 	tree rhs1_etype = rhs1_type;
4088 	tree rhs2_etype = rhs2_type;
4089 	if (TREE_CODE (lhs_type) == VECTOR_TYPE)
4090 	  {
4091 	    if (TREE_CODE (rhs1_type) != VECTOR_TYPE
4092 		|| TREE_CODE (rhs2_type) != VECTOR_TYPE)
4093 	      {
4094 		error ("invalid non-vector operands to vector valued plus");
4095 		return true;
4096 	      }
4097 	    lhs_etype = TREE_TYPE (lhs_type);
4098 	    rhs1_etype = TREE_TYPE (rhs1_type);
4099 	    rhs2_etype = TREE_TYPE (rhs2_type);
4100 	  }
4101 	if (POINTER_TYPE_P (lhs_etype)
4102 	    || POINTER_TYPE_P (rhs1_etype)
4103 	    || POINTER_TYPE_P (rhs2_etype))
4104 	  {
4105 	    error ("invalid (pointer) operands to plus/minus");
4106 	    return true;
4107 	  }
4108 
4109 	/* Continue with generic binary expression handling.  */
4110 	break;
4111       }
4112 
4113     case POINTER_PLUS_EXPR:
4114       {
4115 	if (!POINTER_TYPE_P (rhs1_type)
4116 	    || !useless_type_conversion_p (lhs_type, rhs1_type)
4117 	    || !ptrofftype_p (rhs2_type))
4118 	  {
4119 	    error ("type mismatch in pointer plus expression");
4120 	    debug_generic_stmt (lhs_type);
4121 	    debug_generic_stmt (rhs1_type);
4122 	    debug_generic_stmt (rhs2_type);
4123 	    return true;
4124 	  }
4125 
4126 	return false;
4127       }
4128 
4129     case POINTER_DIFF_EXPR:
4130       {
4131 	if (!POINTER_TYPE_P (rhs1_type)
4132 	    || !POINTER_TYPE_P (rhs2_type)
4133 	    /* Because we special-case pointers to void we allow difference
4134 	       of arbitrary pointers with the same mode.  */
4135 	    || TYPE_MODE (rhs1_type) != TYPE_MODE (rhs2_type)
4136 	    || TREE_CODE (lhs_type) != INTEGER_TYPE
4137 	    || TYPE_UNSIGNED (lhs_type)
4138 	    || TYPE_PRECISION (lhs_type) != TYPE_PRECISION (rhs1_type))
4139 	  {
4140 	    error ("type mismatch in pointer diff expression");
4141 	    debug_generic_stmt (lhs_type);
4142 	    debug_generic_stmt (rhs1_type);
4143 	    debug_generic_stmt (rhs2_type);
4144 	    return true;
4145 	  }
4146 
4147 	return false;
4148       }
4149 
4150     case TRUTH_ANDIF_EXPR:
4151     case TRUTH_ORIF_EXPR:
4152     case TRUTH_AND_EXPR:
4153     case TRUTH_OR_EXPR:
4154     case TRUTH_XOR_EXPR:
4155 
4156       gcc_unreachable ();
4157 
4158     case LT_EXPR:
4159     case LE_EXPR:
4160     case GT_EXPR:
4161     case GE_EXPR:
4162     case EQ_EXPR:
4163     case NE_EXPR:
4164     case UNORDERED_EXPR:
4165     case ORDERED_EXPR:
4166     case UNLT_EXPR:
4167     case UNLE_EXPR:
4168     case UNGT_EXPR:
4169     case UNGE_EXPR:
4170     case UNEQ_EXPR:
4171     case LTGT_EXPR:
4172       /* Comparisons are also binary, but the result type is not
4173 	 connected to the operand types.  */
4174       return verify_gimple_comparison (lhs_type, rhs1, rhs2, rhs_code);
4175 
4176     case WIDEN_MULT_EXPR:
4177       if (TREE_CODE (lhs_type) != INTEGER_TYPE)
4178 	return true;
4179       return ((2 * TYPE_PRECISION (rhs1_type) > TYPE_PRECISION (lhs_type))
4180 	      || (TYPE_PRECISION (rhs1_type) != TYPE_PRECISION (rhs2_type)));
4181 
4182     case WIDEN_SUM_EXPR:
4183       {
4184         if (((TREE_CODE (rhs1_type) != VECTOR_TYPE
4185 	      || TREE_CODE (lhs_type) != VECTOR_TYPE)
4186 	     && ((!INTEGRAL_TYPE_P (rhs1_type)
4187 		  && !SCALAR_FLOAT_TYPE_P (rhs1_type))
4188 		 || (!INTEGRAL_TYPE_P (lhs_type)
4189 		     && !SCALAR_FLOAT_TYPE_P (lhs_type))))
4190 	    || !useless_type_conversion_p (lhs_type, rhs2_type)
4191 	    || maybe_lt (GET_MODE_SIZE (element_mode (rhs2_type)),
4192 			 2 * GET_MODE_SIZE (element_mode (rhs1_type))))
4193           {
4194             error ("type mismatch in widening sum reduction");
4195             debug_generic_expr (lhs_type);
4196             debug_generic_expr (rhs1_type);
4197             debug_generic_expr (rhs2_type);
4198             return true;
4199           }
4200         return false;
4201       }
4202 
4203     case VEC_WIDEN_MULT_HI_EXPR:
4204     case VEC_WIDEN_MULT_LO_EXPR:
4205     case VEC_WIDEN_MULT_EVEN_EXPR:
4206     case VEC_WIDEN_MULT_ODD_EXPR:
4207       {
4208         if (TREE_CODE (rhs1_type) != VECTOR_TYPE
4209             || TREE_CODE (lhs_type) != VECTOR_TYPE
4210 	    || !types_compatible_p (rhs1_type, rhs2_type)
4211 	    || maybe_ne (GET_MODE_SIZE (element_mode (lhs_type)),
4212 			 2 * GET_MODE_SIZE (element_mode (rhs1_type))))
4213           {
4214             error ("type mismatch in vector widening multiplication");
4215             debug_generic_expr (lhs_type);
4216             debug_generic_expr (rhs1_type);
4217             debug_generic_expr (rhs2_type);
4218             return true;
4219           }
4220         return false;
4221       }
4222 
4223     case VEC_PACK_TRUNC_EXPR:
4224       /* ???  We currently use VEC_PACK_TRUNC_EXPR to simply concat
4225 	 vector boolean types.  */
4226       if (VECTOR_BOOLEAN_TYPE_P (lhs_type)
4227 	  && VECTOR_BOOLEAN_TYPE_P (rhs1_type)
4228 	  && types_compatible_p (rhs1_type, rhs2_type)
4229 	  && known_eq (TYPE_VECTOR_SUBPARTS (lhs_type),
4230 		       2 * TYPE_VECTOR_SUBPARTS (rhs1_type)))
4231 	return false;
4232 
4233       /* Fallthru.  */
4234     case VEC_PACK_SAT_EXPR:
4235     case VEC_PACK_FIX_TRUNC_EXPR:
4236       {
4237         if (TREE_CODE (rhs1_type) != VECTOR_TYPE
4238             || TREE_CODE (lhs_type) != VECTOR_TYPE
4239             || !((rhs_code == VEC_PACK_FIX_TRUNC_EXPR
4240 		  && SCALAR_FLOAT_TYPE_P (TREE_TYPE (rhs1_type))
4241 		  && INTEGRAL_TYPE_P (TREE_TYPE (lhs_type)))
4242 		 || (INTEGRAL_TYPE_P (TREE_TYPE (rhs1_type))
4243 		     == INTEGRAL_TYPE_P (TREE_TYPE (lhs_type))))
4244 	    || !types_compatible_p (rhs1_type, rhs2_type)
4245 	    || maybe_ne (GET_MODE_SIZE (element_mode (rhs1_type)),
4246 			 2 * GET_MODE_SIZE (element_mode (lhs_type))))
4247           {
4248             error ("type mismatch in vector pack expression");
4249             debug_generic_expr (lhs_type);
4250             debug_generic_expr (rhs1_type);
4251             debug_generic_expr (rhs2_type);
4252             return true;
4253           }
4254 
4255         return false;
4256       }
4257 
4258     case MULT_EXPR:
4259     case MULT_HIGHPART_EXPR:
4260     case TRUNC_DIV_EXPR:
4261     case CEIL_DIV_EXPR:
4262     case FLOOR_DIV_EXPR:
4263     case ROUND_DIV_EXPR:
4264     case TRUNC_MOD_EXPR:
4265     case CEIL_MOD_EXPR:
4266     case FLOOR_MOD_EXPR:
4267     case ROUND_MOD_EXPR:
4268     case RDIV_EXPR:
4269     case EXACT_DIV_EXPR:
4270     case MIN_EXPR:
4271     case MAX_EXPR:
4272     case BIT_IOR_EXPR:
4273     case BIT_XOR_EXPR:
4274     case BIT_AND_EXPR:
4275       /* Continue with generic binary expression handling.  */
4276       break;
4277 
4278     case VEC_SERIES_EXPR:
4279       if (!useless_type_conversion_p (rhs1_type, rhs2_type))
4280 	{
4281 	  error ("type mismatch in series expression");
4282 	  debug_generic_expr (rhs1_type);
4283 	  debug_generic_expr (rhs2_type);
4284 	  return true;
4285 	}
4286       if (TREE_CODE (lhs_type) != VECTOR_TYPE
4287 	  || !useless_type_conversion_p (TREE_TYPE (lhs_type), rhs1_type))
4288 	{
4289 	  error ("vector type expected in series expression");
4290 	  debug_generic_expr (lhs_type);
4291 	  return true;
4292 	}
4293       return false;
4294 
4295     default:
4296       gcc_unreachable ();
4297     }
4298 
4299   if (!useless_type_conversion_p (lhs_type, rhs1_type)
4300       || !useless_type_conversion_p (lhs_type, rhs2_type))
4301     {
4302       error ("type mismatch in binary expression");
4303       debug_generic_stmt (lhs_type);
4304       debug_generic_stmt (rhs1_type);
4305       debug_generic_stmt (rhs2_type);
4306       return true;
4307     }
4308 
4309   return false;
4310 }
4311 
4312 /* Verify a gimple assignment statement STMT with a ternary rhs.
4313    Returns true if anything is wrong.  */
4314 
4315 static bool
4316 verify_gimple_assign_ternary (gassign *stmt)
4317 {
4318   enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
4319   tree lhs = gimple_assign_lhs (stmt);
4320   tree lhs_type = TREE_TYPE (lhs);
4321   tree rhs1 = gimple_assign_rhs1 (stmt);
4322   tree rhs1_type = TREE_TYPE (rhs1);
4323   tree rhs2 = gimple_assign_rhs2 (stmt);
4324   tree rhs2_type = TREE_TYPE (rhs2);
4325   tree rhs3 = gimple_assign_rhs3 (stmt);
4326   tree rhs3_type = TREE_TYPE (rhs3);
4327 
4328   if (!is_gimple_reg (lhs))
4329     {
4330       error ("non-register as LHS of ternary operation");
4331       return true;
4332     }
4333 
4334   if (((rhs_code == VEC_COND_EXPR || rhs_code == COND_EXPR)
4335        ? !is_gimple_condexpr (rhs1) : !is_gimple_val (rhs1))
4336       || !is_gimple_val (rhs2)
4337       || !is_gimple_val (rhs3))
4338     {
4339       error ("invalid operands in ternary operation");
4340       return true;
4341     }
4342 
4343   /* First handle operations that involve different types.  */
4344   switch (rhs_code)
4345     {
4346     case WIDEN_MULT_PLUS_EXPR:
4347     case WIDEN_MULT_MINUS_EXPR:
4348       if ((!INTEGRAL_TYPE_P (rhs1_type)
4349 	   && !FIXED_POINT_TYPE_P (rhs1_type))
4350 	  || !useless_type_conversion_p (rhs1_type, rhs2_type)
4351 	  || !useless_type_conversion_p (lhs_type, rhs3_type)
4352 	  || 2 * TYPE_PRECISION (rhs1_type) > TYPE_PRECISION (lhs_type)
4353 	  || TYPE_PRECISION (rhs1_type) != TYPE_PRECISION (rhs2_type))
4354 	{
4355 	  error ("type mismatch in widening multiply-accumulate expression");
4356 	  debug_generic_expr (lhs_type);
4357 	  debug_generic_expr (rhs1_type);
4358 	  debug_generic_expr (rhs2_type);
4359 	  debug_generic_expr (rhs3_type);
4360 	  return true;
4361 	}
4362       break;
4363 
4364     case FMA_EXPR:
4365       if (!useless_type_conversion_p (lhs_type, rhs1_type)
4366 	  || !useless_type_conversion_p (lhs_type, rhs2_type)
4367 	  || !useless_type_conversion_p (lhs_type, rhs3_type))
4368 	{
4369 	  error ("type mismatch in fused multiply-add expression");
4370 	  debug_generic_expr (lhs_type);
4371 	  debug_generic_expr (rhs1_type);
4372 	  debug_generic_expr (rhs2_type);
4373 	  debug_generic_expr (rhs3_type);
4374 	  return true;
4375 	}
4376       break;
4377 
4378     case VEC_COND_EXPR:
4379       if (!VECTOR_BOOLEAN_TYPE_P (rhs1_type)
4380 	  || maybe_ne (TYPE_VECTOR_SUBPARTS (rhs1_type),
4381 		       TYPE_VECTOR_SUBPARTS (lhs_type)))
4382 	{
4383 	  error ("the first argument of a VEC_COND_EXPR must be of a "
4384 		 "boolean vector type of the same number of elements "
4385 		 "as the result");
4386 	  debug_generic_expr (lhs_type);
4387 	  debug_generic_expr (rhs1_type);
4388 	  return true;
4389 	}
4390       /* Fallthrough.  */
4391     case COND_EXPR:
4392       if (!useless_type_conversion_p (lhs_type, rhs2_type)
4393 	  || !useless_type_conversion_p (lhs_type, rhs3_type))
4394 	{
4395 	  error ("type mismatch in conditional expression");
4396 	  debug_generic_expr (lhs_type);
4397 	  debug_generic_expr (rhs2_type);
4398 	  debug_generic_expr (rhs3_type);
4399 	  return true;
4400 	}
4401       break;
4402 
4403     case VEC_PERM_EXPR:
4404       if (!useless_type_conversion_p (lhs_type, rhs1_type)
4405 	  || !useless_type_conversion_p (lhs_type, rhs2_type))
4406 	{
4407 	  error ("type mismatch in vector permute expression");
4408 	  debug_generic_expr (lhs_type);
4409 	  debug_generic_expr (rhs1_type);
4410 	  debug_generic_expr (rhs2_type);
4411 	  debug_generic_expr (rhs3_type);
4412 	  return true;
4413 	}
4414 
4415       if (TREE_CODE (rhs1_type) != VECTOR_TYPE
4416 	  || TREE_CODE (rhs2_type) != VECTOR_TYPE
4417 	  || TREE_CODE (rhs3_type) != VECTOR_TYPE)
4418 	{
4419 	  error ("vector types expected in vector permute expression");
4420 	  debug_generic_expr (lhs_type);
4421 	  debug_generic_expr (rhs1_type);
4422 	  debug_generic_expr (rhs2_type);
4423 	  debug_generic_expr (rhs3_type);
4424 	  return true;
4425 	}
4426 
4427       if (maybe_ne (TYPE_VECTOR_SUBPARTS (rhs1_type),
4428 		    TYPE_VECTOR_SUBPARTS (rhs2_type))
4429 	  || maybe_ne (TYPE_VECTOR_SUBPARTS (rhs2_type),
4430 		       TYPE_VECTOR_SUBPARTS (rhs3_type))
4431 	  || maybe_ne (TYPE_VECTOR_SUBPARTS (rhs3_type),
4432 		       TYPE_VECTOR_SUBPARTS (lhs_type)))
4433 	{
4434 	  error ("vectors with different element number found "
4435 		 "in vector permute expression");
4436 	  debug_generic_expr (lhs_type);
4437 	  debug_generic_expr (rhs1_type);
4438 	  debug_generic_expr (rhs2_type);
4439 	  debug_generic_expr (rhs3_type);
4440 	  return true;
4441 	}
4442 
4443       if (TREE_CODE (TREE_TYPE (rhs3_type)) != INTEGER_TYPE
4444 	  || (TREE_CODE (rhs3) != VECTOR_CST
4445 	      && (GET_MODE_BITSIZE (SCALAR_INT_TYPE_MODE
4446 				    (TREE_TYPE (rhs3_type)))
4447 		  != GET_MODE_BITSIZE (SCALAR_TYPE_MODE
4448 				       (TREE_TYPE (rhs1_type))))))
4449 	{
4450 	  error ("invalid mask type in vector permute expression");
4451 	  debug_generic_expr (lhs_type);
4452 	  debug_generic_expr (rhs1_type);
4453 	  debug_generic_expr (rhs2_type);
4454 	  debug_generic_expr (rhs3_type);
4455 	  return true;
4456 	}
4457 
4458       return false;
4459 
4460     case SAD_EXPR:
4461       if (!useless_type_conversion_p (rhs1_type, rhs2_type)
4462 	  || !useless_type_conversion_p (lhs_type, rhs3_type)
4463 	  || 2 * GET_MODE_UNIT_BITSIZE (TYPE_MODE (TREE_TYPE (rhs1_type)))
4464 	       > GET_MODE_UNIT_BITSIZE (TYPE_MODE (TREE_TYPE (lhs_type))))
4465 	{
4466 	  error ("type mismatch in sad expression");
4467 	  debug_generic_expr (lhs_type);
4468 	  debug_generic_expr (rhs1_type);
4469 	  debug_generic_expr (rhs2_type);
4470 	  debug_generic_expr (rhs3_type);
4471 	  return true;
4472 	}
4473 
4474       if (TREE_CODE (rhs1_type) != VECTOR_TYPE
4475 	  || TREE_CODE (rhs2_type) != VECTOR_TYPE
4476 	  || TREE_CODE (rhs3_type) != VECTOR_TYPE)
4477 	{
4478 	  error ("vector types expected in sad expression");
4479 	  debug_generic_expr (lhs_type);
4480 	  debug_generic_expr (rhs1_type);
4481 	  debug_generic_expr (rhs2_type);
4482 	  debug_generic_expr (rhs3_type);
4483 	  return true;
4484 	}
4485 
4486       return false;
4487 
4488     case BIT_INSERT_EXPR:
4489       if (! useless_type_conversion_p (lhs_type, rhs1_type))
4490 	{
4491 	  error ("type mismatch in BIT_INSERT_EXPR");
4492 	  debug_generic_expr (lhs_type);
4493 	  debug_generic_expr (rhs1_type);
4494 	  return true;
4495 	}
4496       if (! ((INTEGRAL_TYPE_P (rhs1_type)
4497 	      && INTEGRAL_TYPE_P (rhs2_type))
4498 	     || (VECTOR_TYPE_P (rhs1_type)
4499 		 && types_compatible_p (TREE_TYPE (rhs1_type), rhs2_type))))
4500 	{
4501 	  error ("not allowed type combination in BIT_INSERT_EXPR");
4502 	  debug_generic_expr (rhs1_type);
4503 	  debug_generic_expr (rhs2_type);
4504 	  return true;
4505 	}
4506       if (! tree_fits_uhwi_p (rhs3)
4507 	  || ! types_compatible_p (bitsizetype, TREE_TYPE (rhs3))
4508 	  || ! tree_fits_uhwi_p (TYPE_SIZE (rhs2_type)))
4509 	{
4510 	  error ("invalid position or size in BIT_INSERT_EXPR");
4511 	  return true;
4512 	}
4513       if (INTEGRAL_TYPE_P (rhs1_type))
4514 	{
4515 	  unsigned HOST_WIDE_INT bitpos = tree_to_uhwi (rhs3);
4516 	  if (bitpos >= TYPE_PRECISION (rhs1_type)
4517 	      || (bitpos + TYPE_PRECISION (rhs2_type)
4518 		  > TYPE_PRECISION (rhs1_type)))
4519 	    {
4520 	      error ("insertion out of range in BIT_INSERT_EXPR");
4521 	      return true;
4522 	    }
4523 	}
4524       else if (VECTOR_TYPE_P (rhs1_type))
4525 	{
4526 	  unsigned HOST_WIDE_INT bitpos = tree_to_uhwi (rhs3);
4527 	  unsigned HOST_WIDE_INT bitsize = tree_to_uhwi (TYPE_SIZE (rhs2_type));
4528 	  if (bitpos % bitsize != 0)
4529 	    {
4530 	      error ("vector insertion not at element boundary");
4531 	      return true;
4532 	    }
4533 	}
4534       return false;
4535 
4536     case DOT_PROD_EXPR:
4537       {
4538         if (((TREE_CODE (rhs1_type) != VECTOR_TYPE
4539 	      || TREE_CODE (lhs_type) != VECTOR_TYPE)
4540 	     && ((!INTEGRAL_TYPE_P (rhs1_type)
4541 		  && !SCALAR_FLOAT_TYPE_P (rhs1_type))
4542 		 || (!INTEGRAL_TYPE_P (lhs_type)
4543 		     && !SCALAR_FLOAT_TYPE_P (lhs_type))))
4544 	    || !types_compatible_p (rhs1_type, rhs2_type)
4545 	    || !useless_type_conversion_p (lhs_type, rhs3_type)
4546 	    || maybe_lt (GET_MODE_SIZE (element_mode (rhs3_type)),
4547 			 2 * GET_MODE_SIZE (element_mode (rhs1_type))))
4548           {
4549             error ("type mismatch in dot product reduction");
4550             debug_generic_expr (lhs_type);
4551             debug_generic_expr (rhs1_type);
4552             debug_generic_expr (rhs2_type);
4553             return true;
4554           }
4555         return false;
4556       }
4557 
4558     case REALIGN_LOAD_EXPR:
4559       /* FIXME.  */
4560       return false;
4561 
4562     default:
4563       gcc_unreachable ();
4564     }
4565   return false;
4566 }
4567 
4568 /* Verify a gimple assignment statement STMT with a single rhs.
4569    Returns true if anything is wrong.  */
4570 
4571 static bool
4572 verify_gimple_assign_single (gassign *stmt)
4573 {
4574   enum tree_code rhs_code = gimple_assign_rhs_code (stmt);
4575   tree lhs = gimple_assign_lhs (stmt);
4576   tree lhs_type = TREE_TYPE (lhs);
4577   tree rhs1 = gimple_assign_rhs1 (stmt);
4578   tree rhs1_type = TREE_TYPE (rhs1);
4579   bool res = false;
4580 
4581   if (!useless_type_conversion_p (lhs_type, rhs1_type))
4582     {
4583       error ("non-trivial conversion at assignment");
4584       debug_generic_expr (lhs_type);
4585       debug_generic_expr (rhs1_type);
4586       return true;
4587     }
4588 
4589   if (gimple_clobber_p (stmt)
4590       && !(DECL_P (lhs) || TREE_CODE (lhs) == MEM_REF))
4591     {
4592       error ("non-decl/MEM_REF LHS in clobber statement");
4593       debug_generic_expr (lhs);
4594       return true;
4595     }
4596 
4597   if (handled_component_p (lhs)
4598       || TREE_CODE (lhs) == MEM_REF
4599       || TREE_CODE (lhs) == TARGET_MEM_REF)
4600     res |= verify_types_in_gimple_reference (lhs, true);
4601 
4602   /* Special codes we cannot handle via their class.  */
4603   switch (rhs_code)
4604     {
4605     case ADDR_EXPR:
4606       {
4607 	tree op = TREE_OPERAND (rhs1, 0);
4608 	if (!is_gimple_addressable (op))
4609 	  {
4610 	    error ("invalid operand in unary expression");
4611 	    return true;
4612 	  }
4613 
4614 	/* Technically there is no longer a need for matching types, but
4615 	   gimple hygiene asks for this check.  In LTO we can end up
4616 	   combining incompatible units and thus end up with addresses
4617 	   of globals that change their type to a common one.  */
4618 	if (!in_lto_p
4619 	    && !types_compatible_p (TREE_TYPE (op),
4620 				    TREE_TYPE (TREE_TYPE (rhs1)))
4621 	    && !one_pointer_to_useless_type_conversion_p (TREE_TYPE (rhs1),
4622 							  TREE_TYPE (op)))
4623 	  {
4624 	    error ("type mismatch in address expression");
4625 	    debug_generic_stmt (TREE_TYPE (rhs1));
4626 	    debug_generic_stmt (TREE_TYPE (op));
4627 	    return true;
4628 	  }
4629 
4630 	return verify_types_in_gimple_reference (op, true);
4631       }
4632 
4633     /* tcc_reference  */
4634     case INDIRECT_REF:
4635       error ("INDIRECT_REF in gimple IL");
4636       return true;
4637 
4638     case COMPONENT_REF:
4639     case BIT_FIELD_REF:
4640     case ARRAY_REF:
4641     case ARRAY_RANGE_REF:
4642     case VIEW_CONVERT_EXPR:
4643     case REALPART_EXPR:
4644     case IMAGPART_EXPR:
4645     case TARGET_MEM_REF:
4646     case MEM_REF:
4647       if (!is_gimple_reg (lhs)
4648 	  && is_gimple_reg_type (TREE_TYPE (lhs)))
4649 	{
4650 	  error ("invalid rhs for gimple memory store");
4651 	  debug_generic_stmt (lhs);
4652 	  debug_generic_stmt (rhs1);
4653 	  return true;
4654 	}
4655       return res || verify_types_in_gimple_reference (rhs1, false);
4656 
4657     /* tcc_constant  */
4658     case SSA_NAME:
4659     case INTEGER_CST:
4660     case REAL_CST:
4661     case FIXED_CST:
4662     case COMPLEX_CST:
4663     case VECTOR_CST:
4664     case STRING_CST:
4665       return res;
4666 
4667     /* tcc_declaration  */
4668     case CONST_DECL:
4669       return res;
4670     case VAR_DECL:
4671     case PARM_DECL:
4672       if (!is_gimple_reg (lhs)
4673 	  && !is_gimple_reg (rhs1)
4674 	  && is_gimple_reg_type (TREE_TYPE (lhs)))
4675 	{
4676 	  error ("invalid rhs for gimple memory store");
4677 	  debug_generic_stmt (lhs);
4678 	  debug_generic_stmt (rhs1);
4679 	  return true;
4680 	}
4681       return res;
4682 
4683     case CONSTRUCTOR:
4684       if (TREE_CODE (rhs1_type) == VECTOR_TYPE)
4685 	{
4686 	  unsigned int i;
4687 	  tree elt_i, elt_v, elt_t = NULL_TREE;
4688 
4689 	  if (CONSTRUCTOR_NELTS (rhs1) == 0)
4690 	    return res;
4691 	  /* For vector CONSTRUCTORs we require that either it is empty
4692 	     CONSTRUCTOR, or it is a CONSTRUCTOR of smaller vector elements
4693 	     (then the element count must be correct to cover the whole
4694 	     outer vector and index must be NULL on all elements, or it is
4695 	     a CONSTRUCTOR of scalar elements, where we as an exception allow
4696 	     smaller number of elements (assuming zero filling) and
4697 	     consecutive indexes as compared to NULL indexes (such
4698 	     CONSTRUCTORs can appear in the IL from FEs).  */
4699 	  FOR_EACH_CONSTRUCTOR_ELT (CONSTRUCTOR_ELTS (rhs1), i, elt_i, elt_v)
4700 	    {
4701 	      if (elt_t == NULL_TREE)
4702 		{
4703 		  elt_t = TREE_TYPE (elt_v);
4704 		  if (TREE_CODE (elt_t) == VECTOR_TYPE)
4705 		    {
4706 		      tree elt_t = TREE_TYPE (elt_v);
4707 		      if (!useless_type_conversion_p (TREE_TYPE (rhs1_type),
4708 						      TREE_TYPE (elt_t)))
4709 			{
4710 			  error ("incorrect type of vector CONSTRUCTOR"
4711 				 " elements");
4712 			  debug_generic_stmt (rhs1);
4713 			  return true;
4714 			}
4715 		      else if (maybe_ne (CONSTRUCTOR_NELTS (rhs1)
4716 					 * TYPE_VECTOR_SUBPARTS (elt_t),
4717 					 TYPE_VECTOR_SUBPARTS (rhs1_type)))
4718 			{
4719 			  error ("incorrect number of vector CONSTRUCTOR"
4720 				 " elements");
4721 			  debug_generic_stmt (rhs1);
4722 			  return true;
4723 			}
4724 		    }
4725 		  else if (!useless_type_conversion_p (TREE_TYPE (rhs1_type),
4726 						       elt_t))
4727 		    {
4728 		      error ("incorrect type of vector CONSTRUCTOR elements");
4729 		      debug_generic_stmt (rhs1);
4730 		      return true;
4731 		    }
4732 		  else if (maybe_gt (CONSTRUCTOR_NELTS (rhs1),
4733 				     TYPE_VECTOR_SUBPARTS (rhs1_type)))
4734 		    {
4735 		      error ("incorrect number of vector CONSTRUCTOR elements");
4736 		      debug_generic_stmt (rhs1);
4737 		      return true;
4738 		    }
4739 		}
4740 	      else if (!useless_type_conversion_p (elt_t, TREE_TYPE (elt_v)))
4741 		{
4742 		  error ("incorrect type of vector CONSTRUCTOR elements");
4743 		  debug_generic_stmt (rhs1);
4744 		  return true;
4745 		}
4746 	      if (elt_i != NULL_TREE
4747 		  && (TREE_CODE (elt_t) == VECTOR_TYPE
4748 		      || TREE_CODE (elt_i) != INTEGER_CST
4749 		      || compare_tree_int (elt_i, i) != 0))
4750 		{
4751 		  error ("vector CONSTRUCTOR with non-NULL element index");
4752 		  debug_generic_stmt (rhs1);
4753 		  return true;
4754 		}
4755 	      if (!is_gimple_val (elt_v))
4756 		{
4757 		  error ("vector CONSTRUCTOR element is not a GIMPLE value");
4758 		  debug_generic_stmt (rhs1);
4759 		  return true;
4760 		}
4761 	    }
4762 	}
4763       else if (CONSTRUCTOR_NELTS (rhs1) != 0)
4764 	{
4765 	  error ("non-vector CONSTRUCTOR with elements");
4766 	  debug_generic_stmt (rhs1);
4767 	  return true;
4768 	}
4769       return res;
4770     case OBJ_TYPE_REF:
4771     case ASSERT_EXPR:
4772     case WITH_SIZE_EXPR:
4773       /* FIXME.  */
4774       return res;
4775 
4776     default:;
4777     }
4778 
4779   return res;
4780 }
4781 
4782 /* Verify the contents of a GIMPLE_ASSIGN STMT.  Returns true when there
4783    is a problem, otherwise false.  */
4784 
4785 static bool
4786 verify_gimple_assign (gassign *stmt)
4787 {
4788   switch (gimple_assign_rhs_class (stmt))
4789     {
4790     case GIMPLE_SINGLE_RHS:
4791       return verify_gimple_assign_single (stmt);
4792 
4793     case GIMPLE_UNARY_RHS:
4794       return verify_gimple_assign_unary (stmt);
4795 
4796     case GIMPLE_BINARY_RHS:
4797       return verify_gimple_assign_binary (stmt);
4798 
4799     case GIMPLE_TERNARY_RHS:
4800       return verify_gimple_assign_ternary (stmt);
4801 
4802     default:
4803       gcc_unreachable ();
4804     }
4805 }
4806 
4807 /* Verify the contents of a GIMPLE_RETURN STMT.  Returns true when there
4808    is a problem, otherwise false.  */
4809 
4810 static bool
4811 verify_gimple_return (greturn *stmt)
4812 {
4813   tree op = gimple_return_retval (stmt);
4814   tree restype = TREE_TYPE (TREE_TYPE (cfun->decl));
4815 
4816   /* We cannot test for present return values as we do not fix up missing
4817      return values from the original source.  */
4818   if (op == NULL)
4819     return false;
4820 
4821   if (!is_gimple_val (op)
4822       && TREE_CODE (op) != RESULT_DECL)
4823     {
4824       error ("invalid operand in return statement");
4825       debug_generic_stmt (op);
4826       return true;
4827     }
4828 
4829   if ((TREE_CODE (op) == RESULT_DECL
4830        && DECL_BY_REFERENCE (op))
4831       || (TREE_CODE (op) == SSA_NAME
4832 	  && SSA_NAME_VAR (op)
4833 	  && TREE_CODE (SSA_NAME_VAR (op)) == RESULT_DECL
4834 	  && DECL_BY_REFERENCE (SSA_NAME_VAR (op))))
4835     op = TREE_TYPE (op);
4836 
4837   if (!useless_type_conversion_p (restype, TREE_TYPE (op)))
4838     {
4839       error ("invalid conversion in return statement");
4840       debug_generic_stmt (restype);
4841       debug_generic_stmt (TREE_TYPE (op));
4842       return true;
4843     }
4844 
4845   return false;
4846 }
4847 
4848 
4849 /* Verify the contents of a GIMPLE_GOTO STMT.  Returns true when there
4850    is a problem, otherwise false.  */
4851 
4852 static bool
4853 verify_gimple_goto (ggoto *stmt)
4854 {
4855   tree dest = gimple_goto_dest (stmt);
4856 
4857   /* ???  We have two canonical forms of direct goto destinations, a
4858      bare LABEL_DECL and an ADDR_EXPR of a LABEL_DECL.  */
4859   if (TREE_CODE (dest) != LABEL_DECL
4860       && (!is_gimple_val (dest)
4861 	  || !POINTER_TYPE_P (TREE_TYPE (dest))))
4862     {
4863       error ("goto destination is neither a label nor a pointer");
4864       return true;
4865     }
4866 
4867   return false;
4868 }
4869 
4870 /* Verify the contents of a GIMPLE_SWITCH STMT.  Returns true when there
4871    is a problem, otherwise false.  */
4872 
4873 static bool
4874 verify_gimple_switch (gswitch *stmt)
4875 {
4876   unsigned int i, n;
4877   tree elt, prev_upper_bound = NULL_TREE;
4878   tree index_type, elt_type = NULL_TREE;
4879 
4880   if (!is_gimple_val (gimple_switch_index (stmt)))
4881     {
4882       error ("invalid operand to switch statement");
4883       debug_generic_stmt (gimple_switch_index (stmt));
4884       return true;
4885     }
4886 
4887   index_type = TREE_TYPE (gimple_switch_index (stmt));
4888   if (! INTEGRAL_TYPE_P (index_type))
4889     {
4890       error ("non-integral type switch statement");
4891       debug_generic_expr (index_type);
4892       return true;
4893     }
4894 
4895   elt = gimple_switch_label (stmt, 0);
4896   if (CASE_LOW (elt) != NULL_TREE || CASE_HIGH (elt) != NULL_TREE)
4897     {
4898       error ("invalid default case label in switch statement");
4899       debug_generic_expr (elt);
4900       return true;
4901     }
4902 
4903   n = gimple_switch_num_labels (stmt);
4904   for (i = 1; i < n; i++)
4905     {
4906       elt = gimple_switch_label (stmt, i);
4907 
4908       if (! CASE_LOW (elt))
4909 	{
4910 	  error ("invalid case label in switch statement");
4911 	  debug_generic_expr (elt);
4912 	  return true;
4913 	}
4914       if (CASE_HIGH (elt)
4915 	  && ! tree_int_cst_lt (CASE_LOW (elt), CASE_HIGH (elt)))
4916 	{
4917 	  error ("invalid case range in switch statement");
4918 	  debug_generic_expr (elt);
4919 	  return true;
4920 	}
4921 
4922       if (elt_type)
4923 	{
4924 	  if (TREE_TYPE (CASE_LOW (elt)) != elt_type
4925 	      || (CASE_HIGH (elt) && TREE_TYPE (CASE_HIGH (elt)) != elt_type))
4926 	    {
4927 	      error ("type mismatch for case label in switch statement");
4928 	      debug_generic_expr (elt);
4929 	      return true;
4930 	    }
4931 	}
4932       else
4933 	{
4934 	  elt_type = TREE_TYPE (CASE_LOW (elt));
4935 	  if (TYPE_PRECISION (index_type) < TYPE_PRECISION (elt_type))
4936 	    {
4937 	      error ("type precision mismatch in switch statement");
4938 	      return true;
4939 	    }
4940 	}
4941 
4942       if (prev_upper_bound)
4943 	{
4944 	  if (! tree_int_cst_lt (prev_upper_bound, CASE_LOW (elt)))
4945 	    {
4946 	      error ("case labels not sorted in switch statement");
4947 	      return true;
4948 	    }
4949 	}
4950 
4951       prev_upper_bound = CASE_HIGH (elt);
4952       if (! prev_upper_bound)
4953 	prev_upper_bound = CASE_LOW (elt);
4954     }
4955 
4956   return false;
4957 }
4958 
4959 /* Verify a gimple debug statement STMT.
4960    Returns true if anything is wrong.  */
4961 
4962 static bool
4963 verify_gimple_debug (gimple *stmt ATTRIBUTE_UNUSED)
4964 {
4965   /* There isn't much that could be wrong in a gimple debug stmt.  A
4966      gimple debug bind stmt, for example, maps a tree, that's usually
4967      a VAR_DECL or a PARM_DECL, but that could also be some scalarized
4968      component or member of an aggregate type, to another tree, that
4969      can be an arbitrary expression.  These stmts expand into debug
4970      insns, and are converted to debug notes by var-tracking.c.  */
4971   return false;
4972 }
4973 
4974 /* Verify a gimple label statement STMT.
4975    Returns true if anything is wrong.  */
4976 
4977 static bool
4978 verify_gimple_label (glabel *stmt)
4979 {
4980   tree decl = gimple_label_label (stmt);
4981   int uid;
4982   bool err = false;
4983 
4984   if (TREE_CODE (decl) != LABEL_DECL)
4985     return true;
4986   if (!DECL_NONLOCAL (decl) && !FORCED_LABEL (decl)
4987       && DECL_CONTEXT (decl) != current_function_decl)
4988     {
4989       error ("label's context is not the current function decl");
4990       err |= true;
4991     }
4992 
4993   uid = LABEL_DECL_UID (decl);
4994   if (cfun->cfg
4995       && (uid == -1
4996 	  || (*label_to_block_map_for_fn (cfun))[uid] != gimple_bb (stmt)))
4997     {
4998       error ("incorrect entry in label_to_block_map");
4999       err |= true;
5000     }
5001 
5002   uid = EH_LANDING_PAD_NR (decl);
5003   if (uid)
5004     {
5005       eh_landing_pad lp = get_eh_landing_pad_from_number (uid);
5006       if (decl != lp->post_landing_pad)
5007 	{
5008 	  error ("incorrect setting of landing pad number");
5009 	  err |= true;
5010 	}
5011     }
5012 
5013   return err;
5014 }
5015 
5016 /* Verify a gimple cond statement STMT.
5017    Returns true if anything is wrong.  */
5018 
5019 static bool
5020 verify_gimple_cond (gcond *stmt)
5021 {
5022   if (TREE_CODE_CLASS (gimple_cond_code (stmt)) != tcc_comparison)
5023     {
5024       error ("invalid comparison code in gimple cond");
5025       return true;
5026     }
5027   if (!(!gimple_cond_true_label (stmt)
5028 	|| TREE_CODE (gimple_cond_true_label (stmt)) == LABEL_DECL)
5029       || !(!gimple_cond_false_label (stmt)
5030 	   || TREE_CODE (gimple_cond_false_label (stmt)) == LABEL_DECL))
5031     {
5032       error ("invalid labels in gimple cond");
5033       return true;
5034     }
5035 
5036   return verify_gimple_comparison (boolean_type_node,
5037 				   gimple_cond_lhs (stmt),
5038 				   gimple_cond_rhs (stmt),
5039 				   gimple_cond_code (stmt));
5040 }
5041 
5042 /* Verify the GIMPLE statement STMT.  Returns true if there is an
5043    error, otherwise false.  */
5044 
5045 static bool
5046 verify_gimple_stmt (gimple *stmt)
5047 {
5048   switch (gimple_code (stmt))
5049     {
5050     case GIMPLE_ASSIGN:
5051       return verify_gimple_assign (as_a <gassign *> (stmt));
5052 
5053     case GIMPLE_LABEL:
5054       return verify_gimple_label (as_a <glabel *> (stmt));
5055 
5056     case GIMPLE_CALL:
5057       return verify_gimple_call (as_a <gcall *> (stmt));
5058 
5059     case GIMPLE_COND:
5060       return verify_gimple_cond (as_a <gcond *> (stmt));
5061 
5062     case GIMPLE_GOTO:
5063       return verify_gimple_goto (as_a <ggoto *> (stmt));
5064 
5065     case GIMPLE_SWITCH:
5066       return verify_gimple_switch (as_a <gswitch *> (stmt));
5067 
5068     case GIMPLE_RETURN:
5069       return verify_gimple_return (as_a <greturn *> (stmt));
5070 
5071     case GIMPLE_ASM:
5072       return false;
5073 
5074     case GIMPLE_TRANSACTION:
5075       return verify_gimple_transaction (as_a <gtransaction *> (stmt));
5076 
5077     /* Tuples that do not have tree operands.  */
5078     case GIMPLE_NOP:
5079     case GIMPLE_PREDICT:
5080     case GIMPLE_RESX:
5081     case GIMPLE_EH_DISPATCH:
5082     case GIMPLE_EH_MUST_NOT_THROW:
5083       return false;
5084 
5085     CASE_GIMPLE_OMP:
5086       /* OpenMP directives are validated by the FE and never operated
5087 	 on by the optimizers.  Furthermore, GIMPLE_OMP_FOR may contain
5088 	 non-gimple expressions when the main index variable has had
5089 	 its address taken.  This does not affect the loop itself
5090 	 because the header of an GIMPLE_OMP_FOR is merely used to determine
5091 	 how to setup the parallel iteration.  */
5092       return false;
5093 
5094     case GIMPLE_DEBUG:
5095       return verify_gimple_debug (stmt);
5096 
5097     default:
5098       gcc_unreachable ();
5099     }
5100 }
5101 
5102 /* Verify the contents of a GIMPLE_PHI.  Returns true if there is a problem,
5103    and false otherwise.  */
5104 
5105 static bool
5106 verify_gimple_phi (gimple *phi)
5107 {
5108   bool err = false;
5109   unsigned i;
5110   tree phi_result = gimple_phi_result (phi);
5111   bool virtual_p;
5112 
5113   if (!phi_result)
5114     {
5115       error ("invalid PHI result");
5116       return true;
5117     }
5118 
5119   virtual_p = virtual_operand_p (phi_result);
5120   if (TREE_CODE (phi_result) != SSA_NAME
5121       || (virtual_p
5122 	  && SSA_NAME_VAR (phi_result) != gimple_vop (cfun)))
5123     {
5124       error ("invalid PHI result");
5125       err = true;
5126     }
5127 
5128   for (i = 0; i < gimple_phi_num_args (phi); i++)
5129     {
5130       tree t = gimple_phi_arg_def (phi, i);
5131 
5132       if (!t)
5133 	{
5134 	  error ("missing PHI def");
5135 	  err |= true;
5136 	  continue;
5137 	}
5138       /* Addressable variables do have SSA_NAMEs but they
5139 	 are not considered gimple values.  */
5140       else if ((TREE_CODE (t) == SSA_NAME
5141 		&& virtual_p != virtual_operand_p (t))
5142 	       || (virtual_p
5143 		   && (TREE_CODE (t) != SSA_NAME
5144 		       || SSA_NAME_VAR (t) != gimple_vop (cfun)))
5145 	       || (!virtual_p
5146 		   && !is_gimple_val (t)))
5147 	{
5148 	  error ("invalid PHI argument");
5149 	  debug_generic_expr (t);
5150 	  err |= true;
5151 	}
5152 #ifdef ENABLE_TYPES_CHECKING
5153       if (!useless_type_conversion_p (TREE_TYPE (phi_result), TREE_TYPE (t)))
5154 	{
5155 	  error ("incompatible types in PHI argument %u", i);
5156 	  debug_generic_stmt (TREE_TYPE (phi_result));
5157 	  debug_generic_stmt (TREE_TYPE (t));
5158 	  err |= true;
5159 	}
5160 #endif
5161     }
5162 
5163   return err;
5164 }
5165 
5166 /* Verify the GIMPLE statements inside the sequence STMTS.  */
5167 
5168 static bool
5169 verify_gimple_in_seq_2 (gimple_seq stmts)
5170 {
5171   gimple_stmt_iterator ittr;
5172   bool err = false;
5173 
5174   for (ittr = gsi_start (stmts); !gsi_end_p (ittr); gsi_next (&ittr))
5175     {
5176       gimple *stmt = gsi_stmt (ittr);
5177 
5178       switch (gimple_code (stmt))
5179         {
5180 	case GIMPLE_BIND:
5181 	  err |= verify_gimple_in_seq_2 (
5182                    gimple_bind_body (as_a <gbind *> (stmt)));
5183 	  break;
5184 
5185 	case GIMPLE_TRY:
5186 	  err |= verify_gimple_in_seq_2 (gimple_try_eval (stmt));
5187 	  err |= verify_gimple_in_seq_2 (gimple_try_cleanup (stmt));
5188 	  break;
5189 
5190 	case GIMPLE_EH_FILTER:
5191 	  err |= verify_gimple_in_seq_2 (gimple_eh_filter_failure (stmt));
5192 	  break;
5193 
5194 	case GIMPLE_EH_ELSE:
5195 	  {
5196 	    geh_else *eh_else = as_a <geh_else *> (stmt);
5197 	    err |= verify_gimple_in_seq_2 (gimple_eh_else_n_body (eh_else));
5198 	    err |= verify_gimple_in_seq_2 (gimple_eh_else_e_body (eh_else));
5199 	  }
5200 	  break;
5201 
5202 	case GIMPLE_CATCH:
5203 	  err |= verify_gimple_in_seq_2 (gimple_catch_handler (
5204 					   as_a <gcatch *> (stmt)));
5205 	  break;
5206 
5207 	case GIMPLE_TRANSACTION:
5208 	  err |= verify_gimple_transaction (as_a <gtransaction *> (stmt));
5209 	  break;
5210 
5211 	default:
5212 	  {
5213 	    bool err2 = verify_gimple_stmt (stmt);
5214 	    if (err2)
5215 	      debug_gimple_stmt (stmt);
5216 	    err |= err2;
5217 	  }
5218 	}
5219     }
5220 
5221   return err;
5222 }
5223 
5224 /* Verify the contents of a GIMPLE_TRANSACTION.  Returns true if there
5225    is a problem, otherwise false.  */
5226 
5227 static bool
5228 verify_gimple_transaction (gtransaction *stmt)
5229 {
5230   tree lab;
5231 
5232   lab = gimple_transaction_label_norm (stmt);
5233   if (lab != NULL && TREE_CODE (lab) != LABEL_DECL)
5234     return true;
5235   lab = gimple_transaction_label_uninst (stmt);
5236   if (lab != NULL && TREE_CODE (lab) != LABEL_DECL)
5237     return true;
5238   lab = gimple_transaction_label_over (stmt);
5239   if (lab != NULL && TREE_CODE (lab) != LABEL_DECL)
5240     return true;
5241 
5242   return verify_gimple_in_seq_2 (gimple_transaction_body (stmt));
5243 }
5244 
5245 
5246 /* Verify the GIMPLE statements inside the statement list STMTS.  */
5247 
5248 DEBUG_FUNCTION void
5249 verify_gimple_in_seq (gimple_seq stmts)
5250 {
5251   timevar_push (TV_TREE_STMT_VERIFY);
5252   if (verify_gimple_in_seq_2 (stmts))
5253     internal_error ("verify_gimple failed");
5254   timevar_pop (TV_TREE_STMT_VERIFY);
5255 }
5256 
5257 /* Return true when the T can be shared.  */
5258 
5259 static bool
5260 tree_node_can_be_shared (tree t)
5261 {
5262   if (IS_TYPE_OR_DECL_P (t)
5263       || is_gimple_min_invariant (t)
5264       || TREE_CODE (t) == SSA_NAME
5265       || t == error_mark_node
5266       || TREE_CODE (t) == IDENTIFIER_NODE)
5267     return true;
5268 
5269   if (TREE_CODE (t) == CASE_LABEL_EXPR)
5270     return true;
5271 
5272   if (DECL_P (t))
5273     return true;
5274 
5275   return false;
5276 }
5277 
5278 /* Called via walk_tree.  Verify tree sharing.  */
5279 
5280 static tree
5281 verify_node_sharing_1 (tree *tp, int *walk_subtrees, void *data)
5282 {
5283   hash_set<void *> *visited = (hash_set<void *> *) data;
5284 
5285   if (tree_node_can_be_shared (*tp))
5286     {
5287       *walk_subtrees = false;
5288       return NULL;
5289     }
5290 
5291   if (visited->add (*tp))
5292     return *tp;
5293 
5294   return NULL;
5295 }
5296 
5297 /* Called via walk_gimple_stmt.  Verify tree sharing.  */
5298 
5299 static tree
5300 verify_node_sharing (tree *tp, int *walk_subtrees, void *data)
5301 {
5302   struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
5303   return verify_node_sharing_1 (tp, walk_subtrees, wi->info);
5304 }
5305 
5306 static bool eh_error_found;
5307 bool
5308 verify_eh_throw_stmt_node (gimple *const &stmt, const int &,
5309 			   hash_set<gimple *> *visited)
5310 {
5311   if (!visited->contains (stmt))
5312     {
5313       error ("dead STMT in EH table");
5314       debug_gimple_stmt (stmt);
5315       eh_error_found = true;
5316     }
5317   return true;
5318 }
5319 
5320 /* Verify if the location LOCs block is in BLOCKS.  */
5321 
5322 static bool
5323 verify_location (hash_set<tree> *blocks, location_t loc)
5324 {
5325   tree block = LOCATION_BLOCK (loc);
5326   if (block != NULL_TREE
5327       && !blocks->contains (block))
5328     {
5329       error ("location references block not in block tree");
5330       return true;
5331     }
5332   if (block != NULL_TREE)
5333     return verify_location (blocks, BLOCK_SOURCE_LOCATION (block));
5334   return false;
5335 }
5336 
5337 /* Called via walk_tree.  Verify that expressions have no blocks.  */
5338 
5339 static tree
5340 verify_expr_no_block (tree *tp, int *walk_subtrees, void *)
5341 {
5342   if (!EXPR_P (*tp))
5343     {
5344       *walk_subtrees = false;
5345       return NULL;
5346     }
5347 
5348   location_t loc = EXPR_LOCATION (*tp);
5349   if (LOCATION_BLOCK (loc) != NULL)
5350     return *tp;
5351 
5352   return NULL;
5353 }
5354 
5355 /* Called via walk_tree.  Verify locations of expressions.  */
5356 
5357 static tree
5358 verify_expr_location_1 (tree *tp, int *walk_subtrees, void *data)
5359 {
5360   hash_set<tree> *blocks = (hash_set<tree> *) data;
5361 
5362   if (VAR_P (*tp) && DECL_HAS_DEBUG_EXPR_P (*tp))
5363     {
5364       tree t = DECL_DEBUG_EXPR (*tp);
5365       tree addr = walk_tree (&t, verify_expr_no_block, NULL, NULL);
5366       if (addr)
5367 	return addr;
5368     }
5369   if ((VAR_P (*tp)
5370        || TREE_CODE (*tp) == PARM_DECL
5371        || TREE_CODE (*tp) == RESULT_DECL)
5372       && DECL_HAS_VALUE_EXPR_P (*tp))
5373     {
5374       tree t = DECL_VALUE_EXPR (*tp);
5375       tree addr = walk_tree (&t, verify_expr_no_block, NULL, NULL);
5376       if (addr)
5377 	return addr;
5378     }
5379 
5380   if (!EXPR_P (*tp))
5381     {
5382       *walk_subtrees = false;
5383       return NULL;
5384     }
5385 
5386   location_t loc = EXPR_LOCATION (*tp);
5387   if (verify_location (blocks, loc))
5388     return *tp;
5389 
5390   return NULL;
5391 }
5392 
5393 /* Called via walk_gimple_op.  Verify locations of expressions.  */
5394 
5395 static tree
5396 verify_expr_location (tree *tp, int *walk_subtrees, void *data)
5397 {
5398   struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
5399   return verify_expr_location_1 (tp, walk_subtrees, wi->info);
5400 }
5401 
5402 /* Insert all subblocks of BLOCK into BLOCKS and recurse.  */
5403 
5404 static void
5405 collect_subblocks (hash_set<tree> *blocks, tree block)
5406 {
5407   tree t;
5408   for (t = BLOCK_SUBBLOCKS (block); t; t = BLOCK_CHAIN (t))
5409     {
5410       blocks->add (t);
5411       collect_subblocks (blocks, t);
5412     }
5413 }
5414 
5415 /* Verify the GIMPLE statements in the CFG of FN.  */
5416 
5417 DEBUG_FUNCTION void
5418 verify_gimple_in_cfg (struct function *fn, bool verify_nothrow)
5419 {
5420   basic_block bb;
5421   bool err = false;
5422 
5423   timevar_push (TV_TREE_STMT_VERIFY);
5424   hash_set<void *> visited;
5425   hash_set<gimple *> visited_stmts;
5426 
5427   /* Collect all BLOCKs referenced by the BLOCK tree of FN.  */
5428   hash_set<tree> blocks;
5429   if (DECL_INITIAL (fn->decl))
5430     {
5431       blocks.add (DECL_INITIAL (fn->decl));
5432       collect_subblocks (&blocks, DECL_INITIAL (fn->decl));
5433     }
5434 
5435   FOR_EACH_BB_FN (bb, fn)
5436     {
5437       gimple_stmt_iterator gsi;
5438 
5439       for (gphi_iterator gpi = gsi_start_phis (bb);
5440 	   !gsi_end_p (gpi);
5441 	   gsi_next (&gpi))
5442 	{
5443 	  gphi *phi = gpi.phi ();
5444 	  bool err2 = false;
5445 	  unsigned i;
5446 
5447 	  visited_stmts.add (phi);
5448 
5449 	  if (gimple_bb (phi) != bb)
5450 	    {
5451 	      error ("gimple_bb (phi) is set to a wrong basic block");
5452 	      err2 = true;
5453 	    }
5454 
5455 	  err2 |= verify_gimple_phi (phi);
5456 
5457 	  /* Only PHI arguments have locations.  */
5458 	  if (gimple_location (phi) != UNKNOWN_LOCATION)
5459 	    {
5460 	      error ("PHI node with location");
5461 	      err2 = true;
5462 	    }
5463 
5464 	  for (i = 0; i < gimple_phi_num_args (phi); i++)
5465 	    {
5466 	      tree arg = gimple_phi_arg_def (phi, i);
5467 	      tree addr = walk_tree (&arg, verify_node_sharing_1,
5468 				     &visited, NULL);
5469 	      if (addr)
5470 		{
5471 		  error ("incorrect sharing of tree nodes");
5472 		  debug_generic_expr (addr);
5473 		  err2 |= true;
5474 		}
5475 	      location_t loc = gimple_phi_arg_location (phi, i);
5476 	      if (virtual_operand_p (gimple_phi_result (phi))
5477 		  && loc != UNKNOWN_LOCATION)
5478 		{
5479 		  error ("virtual PHI with argument locations");
5480 		  err2 = true;
5481 		}
5482 	      addr = walk_tree (&arg, verify_expr_location_1, &blocks, NULL);
5483 	      if (addr)
5484 		{
5485 		  debug_generic_expr (addr);
5486 		  err2 = true;
5487 		}
5488 	      err2 |= verify_location (&blocks, loc);
5489 	    }
5490 
5491 	  if (err2)
5492 	    debug_gimple_stmt (phi);
5493 	  err |= err2;
5494 	}
5495 
5496       for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5497 	{
5498 	  gimple *stmt = gsi_stmt (gsi);
5499 	  bool err2 = false;
5500 	  struct walk_stmt_info wi;
5501 	  tree addr;
5502 	  int lp_nr;
5503 
5504 	  visited_stmts.add (stmt);
5505 
5506 	  if (gimple_bb (stmt) != bb)
5507 	    {
5508 	      error ("gimple_bb (stmt) is set to a wrong basic block");
5509 	      err2 = true;
5510 	    }
5511 
5512 	  err2 |= verify_gimple_stmt (stmt);
5513 	  err2 |= verify_location (&blocks, gimple_location (stmt));
5514 
5515 	  memset (&wi, 0, sizeof (wi));
5516 	  wi.info = (void *) &visited;
5517 	  addr = walk_gimple_op (stmt, verify_node_sharing, &wi);
5518 	  if (addr)
5519 	    {
5520 	      error ("incorrect sharing of tree nodes");
5521 	      debug_generic_expr (addr);
5522 	      err2 |= true;
5523 	    }
5524 
5525 	  memset (&wi, 0, sizeof (wi));
5526 	  wi.info = (void *) &blocks;
5527 	  addr = walk_gimple_op (stmt, verify_expr_location, &wi);
5528 	  if (addr)
5529 	    {
5530 	      debug_generic_expr (addr);
5531 	      err2 |= true;
5532 	    }
5533 
5534 	  /* ???  Instead of not checking these stmts at all the walker
5535 	     should know its context via wi.  */
5536 	  if (!is_gimple_debug (stmt)
5537 	      && !is_gimple_omp (stmt))
5538 	    {
5539 	      memset (&wi, 0, sizeof (wi));
5540 	      addr = walk_gimple_op (stmt, verify_expr, &wi);
5541 	      if (addr)
5542 		{
5543 		  debug_generic_expr (addr);
5544 		  inform (gimple_location (stmt), "in statement");
5545 		  err2 |= true;
5546 		}
5547 	    }
5548 
5549 	  /* If the statement is marked as part of an EH region, then it is
5550 	     expected that the statement could throw.  Verify that when we
5551 	     have optimizations that simplify statements such that we prove
5552 	     that they cannot throw, that we update other data structures
5553 	     to match.  */
5554 	  lp_nr = lookup_stmt_eh_lp (stmt);
5555 	  if (lp_nr > 0)
5556 	    {
5557 	      if (!stmt_could_throw_p (stmt))
5558 		{
5559 		  if (verify_nothrow)
5560 		    {
5561 		      error ("statement marked for throw, but doesn%'t");
5562 		      err2 |= true;
5563 		    }
5564 		}
5565 	      else if (!gsi_one_before_end_p (gsi))
5566 		{
5567 		  error ("statement marked for throw in middle of block");
5568 		  err2 |= true;
5569 		}
5570 	    }
5571 
5572 	  if (err2)
5573 	    debug_gimple_stmt (stmt);
5574 	  err |= err2;
5575 	}
5576     }
5577 
5578   eh_error_found = false;
5579   hash_map<gimple *, int> *eh_table = get_eh_throw_stmt_table (cfun);
5580   if (eh_table)
5581     eh_table->traverse<hash_set<gimple *> *, verify_eh_throw_stmt_node>
5582       (&visited_stmts);
5583 
5584   if (err || eh_error_found)
5585     internal_error ("verify_gimple failed");
5586 
5587   verify_histograms ();
5588   timevar_pop (TV_TREE_STMT_VERIFY);
5589 }
5590 
5591 
5592 /* Verifies that the flow information is OK.  */
5593 
5594 static int
5595 gimple_verify_flow_info (void)
5596 {
5597   int err = 0;
5598   basic_block bb;
5599   gimple_stmt_iterator gsi;
5600   gimple *stmt;
5601   edge e;
5602   edge_iterator ei;
5603 
5604   if (ENTRY_BLOCK_PTR_FOR_FN (cfun)->il.gimple.seq
5605       || ENTRY_BLOCK_PTR_FOR_FN (cfun)->il.gimple.phi_nodes)
5606     {
5607       error ("ENTRY_BLOCK has IL associated with it");
5608       err = 1;
5609     }
5610 
5611   if (EXIT_BLOCK_PTR_FOR_FN (cfun)->il.gimple.seq
5612       || EXIT_BLOCK_PTR_FOR_FN (cfun)->il.gimple.phi_nodes)
5613     {
5614       error ("EXIT_BLOCK has IL associated with it");
5615       err = 1;
5616     }
5617 
5618   FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (cfun)->preds)
5619     if (e->flags & EDGE_FALLTHRU)
5620       {
5621 	error ("fallthru to exit from bb %d", e->src->index);
5622 	err = 1;
5623       }
5624 
5625   FOR_EACH_BB_FN (bb, cfun)
5626     {
5627       bool found_ctrl_stmt = false;
5628 
5629       stmt = NULL;
5630 
5631       /* Skip labels on the start of basic block.  */
5632       for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi))
5633 	{
5634 	  tree label;
5635 	  gimple *prev_stmt = stmt;
5636 
5637 	  stmt = gsi_stmt (gsi);
5638 
5639 	  if (gimple_code (stmt) != GIMPLE_LABEL)
5640 	    break;
5641 
5642 	  label = gimple_label_label (as_a <glabel *> (stmt));
5643 	  if (prev_stmt && DECL_NONLOCAL (label))
5644 	    {
5645 	      error ("nonlocal label ");
5646 	      print_generic_expr (stderr, label);
5647 	      fprintf (stderr, " is not first in a sequence of labels in bb %d",
5648 		       bb->index);
5649 	      err = 1;
5650 	    }
5651 
5652 	  if (prev_stmt && EH_LANDING_PAD_NR (label) != 0)
5653 	    {
5654 	      error ("EH landing pad label ");
5655 	      print_generic_expr (stderr, label);
5656 	      fprintf (stderr, " is not first in a sequence of labels in bb %d",
5657 		       bb->index);
5658 	      err = 1;
5659 	    }
5660 
5661 	  if (label_to_block (label) != bb)
5662 	    {
5663 	      error ("label ");
5664 	      print_generic_expr (stderr, label);
5665 	      fprintf (stderr, " to block does not match in bb %d",
5666 		       bb->index);
5667 	      err = 1;
5668 	    }
5669 
5670 	  if (decl_function_context (label) != current_function_decl)
5671 	    {
5672 	      error ("label ");
5673 	      print_generic_expr (stderr, label);
5674 	      fprintf (stderr, " has incorrect context in bb %d",
5675 		       bb->index);
5676 	      err = 1;
5677 	    }
5678 	}
5679 
5680       /* Verify that body of basic block BB is free of control flow.  */
5681       for (; !gsi_end_p (gsi); gsi_next (&gsi))
5682 	{
5683 	  gimple *stmt = gsi_stmt (gsi);
5684 
5685 	  if (found_ctrl_stmt)
5686 	    {
5687 	      error ("control flow in the middle of basic block %d",
5688 		     bb->index);
5689 	      err = 1;
5690 	    }
5691 
5692 	  if (stmt_ends_bb_p (stmt))
5693 	    found_ctrl_stmt = true;
5694 
5695 	  if (glabel *label_stmt = dyn_cast <glabel *> (stmt))
5696 	    {
5697 	      error ("label ");
5698 	      print_generic_expr (stderr, gimple_label_label (label_stmt));
5699 	      fprintf (stderr, " in the middle of basic block %d", bb->index);
5700 	      err = 1;
5701 	    }
5702 	}
5703 
5704       gsi = gsi_last_nondebug_bb (bb);
5705       if (gsi_end_p (gsi))
5706 	continue;
5707 
5708       stmt = gsi_stmt (gsi);
5709 
5710       if (gimple_code (stmt) == GIMPLE_LABEL)
5711 	continue;
5712 
5713       err |= verify_eh_edges (stmt);
5714 
5715       if (is_ctrl_stmt (stmt))
5716 	{
5717 	  FOR_EACH_EDGE (e, ei, bb->succs)
5718 	    if (e->flags & EDGE_FALLTHRU)
5719 	      {
5720 		error ("fallthru edge after a control statement in bb %d",
5721 		       bb->index);
5722 		err = 1;
5723 	      }
5724 	}
5725 
5726       if (gimple_code (stmt) != GIMPLE_COND)
5727 	{
5728 	  /* Verify that there are no edges with EDGE_TRUE/FALSE_FLAG set
5729 	     after anything else but if statement.  */
5730 	  FOR_EACH_EDGE (e, ei, bb->succs)
5731 	    if (e->flags & (EDGE_TRUE_VALUE | EDGE_FALSE_VALUE))
5732 	      {
5733 		error ("true/false edge after a non-GIMPLE_COND in bb %d",
5734 		       bb->index);
5735 		err = 1;
5736 	      }
5737 	}
5738 
5739       switch (gimple_code (stmt))
5740 	{
5741 	case GIMPLE_COND:
5742 	  {
5743 	    edge true_edge;
5744 	    edge false_edge;
5745 
5746 	    extract_true_false_edges_from_block (bb, &true_edge, &false_edge);
5747 
5748 	    if (!true_edge
5749 		|| !false_edge
5750 		|| !(true_edge->flags & EDGE_TRUE_VALUE)
5751 		|| !(false_edge->flags & EDGE_FALSE_VALUE)
5752 		|| (true_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
5753 		|| (false_edge->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL))
5754 		|| EDGE_COUNT (bb->succs) >= 3)
5755 	      {
5756 		error ("wrong outgoing edge flags at end of bb %d",
5757 		       bb->index);
5758 		err = 1;
5759 	      }
5760 	  }
5761 	  break;
5762 
5763 	case GIMPLE_GOTO:
5764 	  if (simple_goto_p (stmt))
5765 	    {
5766 	      error ("explicit goto at end of bb %d", bb->index);
5767 	      err = 1;
5768 	    }
5769 	  else
5770 	    {
5771 	      /* FIXME.  We should double check that the labels in the
5772 		 destination blocks have their address taken.  */
5773 	      FOR_EACH_EDGE (e, ei, bb->succs)
5774 		if ((e->flags & (EDGE_FALLTHRU | EDGE_TRUE_VALUE
5775 				 | EDGE_FALSE_VALUE))
5776 		    || !(e->flags & EDGE_ABNORMAL))
5777 		  {
5778 		    error ("wrong outgoing edge flags at end of bb %d",
5779 			   bb->index);
5780 		    err = 1;
5781 		  }
5782 	    }
5783 	  break;
5784 
5785 	case GIMPLE_CALL:
5786 	  if (!gimple_call_builtin_p (stmt, BUILT_IN_RETURN))
5787 	    break;
5788 	  /* fallthru */
5789 	case GIMPLE_RETURN:
5790 	  if (!single_succ_p (bb)
5791 	      || (single_succ_edge (bb)->flags
5792 		  & (EDGE_FALLTHRU | EDGE_ABNORMAL
5793 		     | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
5794 	    {
5795 	      error ("wrong outgoing edge flags at end of bb %d", bb->index);
5796 	      err = 1;
5797 	    }
5798 	  if (single_succ (bb) != EXIT_BLOCK_PTR_FOR_FN (cfun))
5799 	    {
5800 	      error ("return edge does not point to exit in bb %d",
5801 		     bb->index);
5802 	      err = 1;
5803 	    }
5804 	  break;
5805 
5806 	case GIMPLE_SWITCH:
5807 	  {
5808 	    gswitch *switch_stmt = as_a <gswitch *> (stmt);
5809 	    tree prev;
5810 	    edge e;
5811 	    size_t i, n;
5812 
5813 	    n = gimple_switch_num_labels (switch_stmt);
5814 
5815 	    /* Mark all the destination basic blocks.  */
5816 	    for (i = 0; i < n; ++i)
5817 	      {
5818 		tree lab = CASE_LABEL (gimple_switch_label (switch_stmt, i));
5819 		basic_block label_bb = label_to_block (lab);
5820 		gcc_assert (!label_bb->aux || label_bb->aux == (void *)1);
5821 		label_bb->aux = (void *)1;
5822 	      }
5823 
5824 	    /* Verify that the case labels are sorted.  */
5825 	    prev = gimple_switch_label (switch_stmt, 0);
5826 	    for (i = 1; i < n; ++i)
5827 	      {
5828 		tree c = gimple_switch_label (switch_stmt, i);
5829 		if (!CASE_LOW (c))
5830 		  {
5831 		    error ("found default case not at the start of "
5832 			   "case vector");
5833 		    err = 1;
5834 		    continue;
5835 		  }
5836 		if (CASE_LOW (prev)
5837 		    && !tree_int_cst_lt (CASE_LOW (prev), CASE_LOW (c)))
5838 		  {
5839 		    error ("case labels not sorted: ");
5840 		    print_generic_expr (stderr, prev);
5841 		    fprintf (stderr," is greater than ");
5842 		    print_generic_expr (stderr, c);
5843 		    fprintf (stderr," but comes before it.\n");
5844 		    err = 1;
5845 		  }
5846 		prev = c;
5847 	      }
5848 	    /* VRP will remove the default case if it can prove it will
5849 	       never be executed.  So do not verify there always exists
5850 	       a default case here.  */
5851 
5852 	    FOR_EACH_EDGE (e, ei, bb->succs)
5853 	      {
5854 		if (!e->dest->aux)
5855 		  {
5856 		    error ("extra outgoing edge %d->%d",
5857 			   bb->index, e->dest->index);
5858 		    err = 1;
5859 		  }
5860 
5861 		e->dest->aux = (void *)2;
5862 		if ((e->flags & (EDGE_FALLTHRU | EDGE_ABNORMAL
5863 				 | EDGE_TRUE_VALUE | EDGE_FALSE_VALUE)))
5864 		  {
5865 		    error ("wrong outgoing edge flags at end of bb %d",
5866 			   bb->index);
5867 		    err = 1;
5868 		  }
5869 	      }
5870 
5871 	    /* Check that we have all of them.  */
5872 	    for (i = 0; i < n; ++i)
5873 	      {
5874 		tree lab = CASE_LABEL (gimple_switch_label (switch_stmt, i));
5875 		basic_block label_bb = label_to_block (lab);
5876 
5877 		if (label_bb->aux != (void *)2)
5878 		  {
5879 		    error ("missing edge %i->%i", bb->index, label_bb->index);
5880 		    err = 1;
5881 		  }
5882 	      }
5883 
5884 	    FOR_EACH_EDGE (e, ei, bb->succs)
5885 	      e->dest->aux = (void *)0;
5886 	  }
5887 	  break;
5888 
5889 	case GIMPLE_EH_DISPATCH:
5890 	  err |= verify_eh_dispatch_edge (as_a <geh_dispatch *> (stmt));
5891 	  break;
5892 
5893 	default:
5894 	  break;
5895 	}
5896     }
5897 
5898   if (dom_info_state (CDI_DOMINATORS) >= DOM_NO_FAST_QUERY)
5899     verify_dominators (CDI_DOMINATORS);
5900 
5901   return err;
5902 }
5903 
5904 
5905 /* Updates phi nodes after creating a forwarder block joined
5906    by edge FALLTHRU.  */
5907 
5908 static void
5909 gimple_make_forwarder_block (edge fallthru)
5910 {
5911   edge e;
5912   edge_iterator ei;
5913   basic_block dummy, bb;
5914   tree var;
5915   gphi_iterator gsi;
5916 
5917   dummy = fallthru->src;
5918   bb = fallthru->dest;
5919 
5920   if (single_pred_p (bb))
5921     return;
5922 
5923   /* If we redirected a branch we must create new PHI nodes at the
5924      start of BB.  */
5925   for (gsi = gsi_start_phis (dummy); !gsi_end_p (gsi); gsi_next (&gsi))
5926     {
5927       gphi *phi, *new_phi;
5928 
5929       phi = gsi.phi ();
5930       var = gimple_phi_result (phi);
5931       new_phi = create_phi_node (var, bb);
5932       gimple_phi_set_result (phi, copy_ssa_name (var, phi));
5933       add_phi_arg (new_phi, gimple_phi_result (phi), fallthru,
5934 		   UNKNOWN_LOCATION);
5935     }
5936 
5937   /* Add the arguments we have stored on edges.  */
5938   FOR_EACH_EDGE (e, ei, bb->preds)
5939     {
5940       if (e == fallthru)
5941 	continue;
5942 
5943       flush_pending_stmts (e);
5944     }
5945 }
5946 
5947 
5948 /* Return a non-special label in the head of basic block BLOCK.
5949    Create one if it doesn't exist.  */
5950 
5951 tree
5952 gimple_block_label (basic_block bb)
5953 {
5954   gimple_stmt_iterator i, s = gsi_start_bb (bb);
5955   bool first = true;
5956   tree label;
5957   glabel *stmt;
5958 
5959   for (i = s; !gsi_end_p (i); first = false, gsi_next (&i))
5960     {
5961       stmt = dyn_cast <glabel *> (gsi_stmt (i));
5962       if (!stmt)
5963 	break;
5964       label = gimple_label_label (stmt);
5965       if (!DECL_NONLOCAL (label))
5966 	{
5967 	  if (!first)
5968 	    gsi_move_before (&i, &s);
5969 	  return label;
5970 	}
5971     }
5972 
5973   label = create_artificial_label (UNKNOWN_LOCATION);
5974   stmt = gimple_build_label (label);
5975   gsi_insert_before (&s, stmt, GSI_NEW_STMT);
5976   return label;
5977 }
5978 
5979 
5980 /* Attempt to perform edge redirection by replacing a possibly complex
5981    jump instruction by a goto or by removing the jump completely.
5982    This can apply only if all edges now point to the same block.  The
5983    parameters and return values are equivalent to
5984    redirect_edge_and_branch.  */
5985 
5986 static edge
5987 gimple_try_redirect_by_replacing_jump (edge e, basic_block target)
5988 {
5989   basic_block src = e->src;
5990   gimple_stmt_iterator i;
5991   gimple *stmt;
5992 
5993   /* We can replace or remove a complex jump only when we have exactly
5994      two edges.  */
5995   if (EDGE_COUNT (src->succs) != 2
5996       /* Verify that all targets will be TARGET.  Specifically, the
5997 	 edge that is not E must also go to TARGET.  */
5998       || EDGE_SUCC (src, EDGE_SUCC (src, 0) == e)->dest != target)
5999     return NULL;
6000 
6001   i = gsi_last_bb (src);
6002   if (gsi_end_p (i))
6003     return NULL;
6004 
6005   stmt = gsi_stmt (i);
6006 
6007   if (gimple_code (stmt) == GIMPLE_COND || gimple_code (stmt) == GIMPLE_SWITCH)
6008     {
6009       gsi_remove (&i, true);
6010       e = ssa_redirect_edge (e, target);
6011       e->flags = EDGE_FALLTHRU;
6012       return e;
6013     }
6014 
6015   return NULL;
6016 }
6017 
6018 
6019 /* Redirect E to DEST.  Return NULL on failure.  Otherwise, return the
6020    edge representing the redirected branch.  */
6021 
6022 static edge
6023 gimple_redirect_edge_and_branch (edge e, basic_block dest)
6024 {
6025   basic_block bb = e->src;
6026   gimple_stmt_iterator gsi;
6027   edge ret;
6028   gimple *stmt;
6029 
6030   if (e->flags & EDGE_ABNORMAL)
6031     return NULL;
6032 
6033   if (e->dest == dest)
6034     return NULL;
6035 
6036   if (e->flags & EDGE_EH)
6037     return redirect_eh_edge (e, dest);
6038 
6039   if (e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun))
6040     {
6041       ret = gimple_try_redirect_by_replacing_jump (e, dest);
6042       if (ret)
6043 	return ret;
6044     }
6045 
6046   gsi = gsi_last_nondebug_bb (bb);
6047   stmt = gsi_end_p (gsi) ? NULL : gsi_stmt (gsi);
6048 
6049   switch (stmt ? gimple_code (stmt) : GIMPLE_ERROR_MARK)
6050     {
6051     case GIMPLE_COND:
6052       /* For COND_EXPR, we only need to redirect the edge.  */
6053       break;
6054 
6055     case GIMPLE_GOTO:
6056       /* No non-abnormal edges should lead from a non-simple goto, and
6057 	 simple ones should be represented implicitly.  */
6058       gcc_unreachable ();
6059 
6060     case GIMPLE_SWITCH:
6061       {
6062 	gswitch *switch_stmt = as_a <gswitch *> (stmt);
6063 	tree label = gimple_block_label (dest);
6064         tree cases = get_cases_for_edge (e, switch_stmt);
6065 
6066 	/* If we have a list of cases associated with E, then use it
6067 	   as it's a lot faster than walking the entire case vector.  */
6068 	if (cases)
6069 	  {
6070 	    edge e2 = find_edge (e->src, dest);
6071 	    tree last, first;
6072 
6073 	    first = cases;
6074 	    while (cases)
6075 	      {
6076 		last = cases;
6077 		CASE_LABEL (cases) = label;
6078 		cases = CASE_CHAIN (cases);
6079 	      }
6080 
6081 	    /* If there was already an edge in the CFG, then we need
6082 	       to move all the cases associated with E to E2.  */
6083 	    if (e2)
6084 	      {
6085 		tree cases2 = get_cases_for_edge (e2, switch_stmt);
6086 
6087 		CASE_CHAIN (last) = CASE_CHAIN (cases2);
6088 		CASE_CHAIN (cases2) = first;
6089 	      }
6090 	    bitmap_set_bit (touched_switch_bbs, gimple_bb (stmt)->index);
6091 	  }
6092 	else
6093 	  {
6094 	    size_t i, n = gimple_switch_num_labels (switch_stmt);
6095 
6096 	    for (i = 0; i < n; i++)
6097 	      {
6098 		tree elt = gimple_switch_label (switch_stmt, i);
6099 		if (label_to_block (CASE_LABEL (elt)) == e->dest)
6100 		  CASE_LABEL (elt) = label;
6101 	      }
6102 	  }
6103       }
6104       break;
6105 
6106     case GIMPLE_ASM:
6107       {
6108 	gasm *asm_stmt = as_a <gasm *> (stmt);
6109 	int i, n = gimple_asm_nlabels (asm_stmt);
6110 	tree label = NULL;
6111 
6112 	for (i = 0; i < n; ++i)
6113 	  {
6114 	    tree cons = gimple_asm_label_op (asm_stmt, i);
6115 	    if (label_to_block (TREE_VALUE (cons)) == e->dest)
6116 	      {
6117 		if (!label)
6118 		  label = gimple_block_label (dest);
6119 		TREE_VALUE (cons) = label;
6120 	      }
6121 	  }
6122 
6123 	/* If we didn't find any label matching the former edge in the
6124 	   asm labels, we must be redirecting the fallthrough
6125 	   edge.  */
6126 	gcc_assert (label || (e->flags & EDGE_FALLTHRU));
6127       }
6128       break;
6129 
6130     case GIMPLE_RETURN:
6131       gsi_remove (&gsi, true);
6132       e->flags |= EDGE_FALLTHRU;
6133       break;
6134 
6135     case GIMPLE_OMP_RETURN:
6136     case GIMPLE_OMP_CONTINUE:
6137     case GIMPLE_OMP_SECTIONS_SWITCH:
6138     case GIMPLE_OMP_FOR:
6139       /* The edges from OMP constructs can be simply redirected.  */
6140       break;
6141 
6142     case GIMPLE_EH_DISPATCH:
6143       if (!(e->flags & EDGE_FALLTHRU))
6144 	redirect_eh_dispatch_edge (as_a <geh_dispatch *> (stmt), e, dest);
6145       break;
6146 
6147     case GIMPLE_TRANSACTION:
6148       if (e->flags & EDGE_TM_ABORT)
6149 	gimple_transaction_set_label_over (as_a <gtransaction *> (stmt),
6150 				           gimple_block_label (dest));
6151       else if (e->flags & EDGE_TM_UNINSTRUMENTED)
6152 	gimple_transaction_set_label_uninst (as_a <gtransaction *> (stmt),
6153 				             gimple_block_label (dest));
6154       else
6155 	gimple_transaction_set_label_norm (as_a <gtransaction *> (stmt),
6156 				           gimple_block_label (dest));
6157       break;
6158 
6159     default:
6160       /* Otherwise it must be a fallthru edge, and we don't need to
6161 	 do anything besides redirecting it.  */
6162       gcc_assert (e->flags & EDGE_FALLTHRU);
6163       break;
6164     }
6165 
6166   /* Update/insert PHI nodes as necessary.  */
6167 
6168   /* Now update the edges in the CFG.  */
6169   e = ssa_redirect_edge (e, dest);
6170 
6171   return e;
6172 }
6173 
6174 /* Returns true if it is possible to remove edge E by redirecting
6175    it to the destination of the other edge from E->src.  */
6176 
6177 static bool
6178 gimple_can_remove_branch_p (const_edge e)
6179 {
6180   if (e->flags & (EDGE_ABNORMAL | EDGE_EH))
6181     return false;
6182 
6183   return true;
6184 }
6185 
6186 /* Simple wrapper, as we can always redirect fallthru edges.  */
6187 
6188 static basic_block
6189 gimple_redirect_edge_and_branch_force (edge e, basic_block dest)
6190 {
6191   e = gimple_redirect_edge_and_branch (e, dest);
6192   gcc_assert (e);
6193 
6194   return NULL;
6195 }
6196 
6197 
6198 /* Splits basic block BB after statement STMT (but at least after the
6199    labels).  If STMT is NULL, BB is split just after the labels.  */
6200 
6201 static basic_block
6202 gimple_split_block (basic_block bb, void *stmt)
6203 {
6204   gimple_stmt_iterator gsi;
6205   gimple_stmt_iterator gsi_tgt;
6206   gimple_seq list;
6207   basic_block new_bb;
6208   edge e;
6209   edge_iterator ei;
6210 
6211   new_bb = create_empty_bb (bb);
6212 
6213   /* Redirect the outgoing edges.  */
6214   new_bb->succs = bb->succs;
6215   bb->succs = NULL;
6216   FOR_EACH_EDGE (e, ei, new_bb->succs)
6217     e->src = new_bb;
6218 
6219   /* Get a stmt iterator pointing to the first stmt to move.  */
6220   if (!stmt || gimple_code ((gimple *) stmt) == GIMPLE_LABEL)
6221     gsi = gsi_after_labels (bb);
6222   else
6223     {
6224       gsi = gsi_for_stmt ((gimple *) stmt);
6225       gsi_next (&gsi);
6226     }
6227 
6228   /* Move everything from GSI to the new basic block.  */
6229   if (gsi_end_p (gsi))
6230     return new_bb;
6231 
6232   /* Split the statement list - avoid re-creating new containers as this
6233      brings ugly quadratic memory consumption in the inliner.
6234      (We are still quadratic since we need to update stmt BB pointers,
6235      sadly.)  */
6236   gsi_split_seq_before (&gsi, &list);
6237   set_bb_seq (new_bb, list);
6238   for (gsi_tgt = gsi_start (list);
6239        !gsi_end_p (gsi_tgt); gsi_next (&gsi_tgt))
6240     gimple_set_bb (gsi_stmt (gsi_tgt), new_bb);
6241 
6242   return new_bb;
6243 }
6244 
6245 
6246 /* Moves basic block BB after block AFTER.  */
6247 
6248 static bool
6249 gimple_move_block_after (basic_block bb, basic_block after)
6250 {
6251   if (bb->prev_bb == after)
6252     return true;
6253 
6254   unlink_block (bb);
6255   link_block (bb, after);
6256 
6257   return true;
6258 }
6259 
6260 
6261 /* Return TRUE if block BB has no executable statements, otherwise return
6262    FALSE.  */
6263 
6264 static bool
6265 gimple_empty_block_p (basic_block bb)
6266 {
6267   /* BB must have no executable statements.  */
6268   gimple_stmt_iterator gsi = gsi_after_labels (bb);
6269   if (phi_nodes (bb))
6270     return false;
6271   if (gsi_end_p (gsi))
6272     return true;
6273   if (is_gimple_debug (gsi_stmt (gsi)))
6274     gsi_next_nondebug (&gsi);
6275   return gsi_end_p (gsi);
6276 }
6277 
6278 
6279 /* Split a basic block if it ends with a conditional branch and if the
6280    other part of the block is not empty.  */
6281 
6282 static basic_block
6283 gimple_split_block_before_cond_jump (basic_block bb)
6284 {
6285   gimple *last, *split_point;
6286   gimple_stmt_iterator gsi = gsi_last_nondebug_bb (bb);
6287   if (gsi_end_p (gsi))
6288     return NULL;
6289   last = gsi_stmt (gsi);
6290   if (gimple_code (last) != GIMPLE_COND
6291       && gimple_code (last) != GIMPLE_SWITCH)
6292     return NULL;
6293   gsi_prev (&gsi);
6294   split_point = gsi_stmt (gsi);
6295   return split_block (bb, split_point)->dest;
6296 }
6297 
6298 
6299 /* Return true if basic_block can be duplicated.  */
6300 
6301 static bool
6302 gimple_can_duplicate_bb_p (const_basic_block bb ATTRIBUTE_UNUSED)
6303 {
6304   return true;
6305 }
6306 
6307 /* Create a duplicate of the basic block BB.  NOTE: This does not
6308    preserve SSA form.  */
6309 
6310 static basic_block
6311 gimple_duplicate_bb (basic_block bb)
6312 {
6313   basic_block new_bb;
6314   gimple_stmt_iterator gsi_tgt;
6315 
6316   new_bb = create_empty_bb (EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb);
6317 
6318   /* Copy the PHI nodes.  We ignore PHI node arguments here because
6319      the incoming edges have not been setup yet.  */
6320   for (gphi_iterator gpi = gsi_start_phis (bb);
6321        !gsi_end_p (gpi);
6322        gsi_next (&gpi))
6323     {
6324       gphi *phi, *copy;
6325       phi = gpi.phi ();
6326       copy = create_phi_node (NULL_TREE, new_bb);
6327       create_new_def_for (gimple_phi_result (phi), copy,
6328 			  gimple_phi_result_ptr (copy));
6329       gimple_set_uid (copy, gimple_uid (phi));
6330     }
6331 
6332   gsi_tgt = gsi_start_bb (new_bb);
6333   for (gimple_stmt_iterator gsi = gsi_start_bb (bb);
6334        !gsi_end_p (gsi);
6335        gsi_next (&gsi))
6336     {
6337       def_operand_p def_p;
6338       ssa_op_iter op_iter;
6339       tree lhs;
6340       gimple *stmt, *copy;
6341 
6342       stmt = gsi_stmt (gsi);
6343       if (gimple_code (stmt) == GIMPLE_LABEL)
6344 	continue;
6345 
6346       /* Don't duplicate label debug stmts.  */
6347       if (gimple_debug_bind_p (stmt)
6348 	  && TREE_CODE (gimple_debug_bind_get_var (stmt))
6349 	     == LABEL_DECL)
6350 	continue;
6351 
6352       /* Create a new copy of STMT and duplicate STMT's virtual
6353 	 operands.  */
6354       copy = gimple_copy (stmt);
6355       gsi_insert_after (&gsi_tgt, copy, GSI_NEW_STMT);
6356 
6357       maybe_duplicate_eh_stmt (copy, stmt);
6358       gimple_duplicate_stmt_histograms (cfun, copy, cfun, stmt);
6359 
6360       /* When copying around a stmt writing into a local non-user
6361 	 aggregate, make sure it won't share stack slot with other
6362 	 vars.  */
6363       lhs = gimple_get_lhs (stmt);
6364       if (lhs && TREE_CODE (lhs) != SSA_NAME)
6365 	{
6366 	  tree base = get_base_address (lhs);
6367 	  if (base
6368 	      && (VAR_P (base) || TREE_CODE (base) == RESULT_DECL)
6369 	      && DECL_IGNORED_P (base)
6370 	      && !TREE_STATIC (base)
6371 	      && !DECL_EXTERNAL (base)
6372 	      && (!VAR_P (base) || !DECL_HAS_VALUE_EXPR_P (base)))
6373 	    DECL_NONSHAREABLE (base) = 1;
6374 	}
6375 
6376       /* Create new names for all the definitions created by COPY and
6377 	 add replacement mappings for each new name.  */
6378       FOR_EACH_SSA_DEF_OPERAND (def_p, copy, op_iter, SSA_OP_ALL_DEFS)
6379 	create_new_def_for (DEF_FROM_PTR (def_p), copy, def_p);
6380     }
6381 
6382   return new_bb;
6383 }
6384 
6385 /* Adds phi node arguments for edge E_COPY after basic block duplication.  */
6386 
6387 static void
6388 add_phi_args_after_copy_edge (edge e_copy)
6389 {
6390   basic_block bb, bb_copy = e_copy->src, dest;
6391   edge e;
6392   edge_iterator ei;
6393   gphi *phi, *phi_copy;
6394   tree def;
6395   gphi_iterator psi, psi_copy;
6396 
6397   if (gimple_seq_empty_p (phi_nodes (e_copy->dest)))
6398     return;
6399 
6400   bb = bb_copy->flags & BB_DUPLICATED ? get_bb_original (bb_copy) : bb_copy;
6401 
6402   if (e_copy->dest->flags & BB_DUPLICATED)
6403     dest = get_bb_original (e_copy->dest);
6404   else
6405     dest = e_copy->dest;
6406 
6407   e = find_edge (bb, dest);
6408   if (!e)
6409     {
6410       /* During loop unrolling the target of the latch edge is copied.
6411 	 In this case we are not looking for edge to dest, but to
6412 	 duplicated block whose original was dest.  */
6413       FOR_EACH_EDGE (e, ei, bb->succs)
6414 	{
6415 	  if ((e->dest->flags & BB_DUPLICATED)
6416 	      && get_bb_original (e->dest) == dest)
6417 	    break;
6418 	}
6419 
6420       gcc_assert (e != NULL);
6421     }
6422 
6423   for (psi = gsi_start_phis (e->dest),
6424        psi_copy = gsi_start_phis (e_copy->dest);
6425        !gsi_end_p (psi);
6426        gsi_next (&psi), gsi_next (&psi_copy))
6427     {
6428       phi = psi.phi ();
6429       phi_copy = psi_copy.phi ();
6430       def = PHI_ARG_DEF_FROM_EDGE (phi, e);
6431       add_phi_arg (phi_copy, def, e_copy,
6432 		   gimple_phi_arg_location_from_edge (phi, e));
6433     }
6434 }
6435 
6436 
6437 /* Basic block BB_COPY was created by code duplication.  Add phi node
6438    arguments for edges going out of BB_COPY.  The blocks that were
6439    duplicated have BB_DUPLICATED set.  */
6440 
6441 void
6442 add_phi_args_after_copy_bb (basic_block bb_copy)
6443 {
6444   edge e_copy;
6445   edge_iterator ei;
6446 
6447   FOR_EACH_EDGE (e_copy, ei, bb_copy->succs)
6448     {
6449       add_phi_args_after_copy_edge (e_copy);
6450     }
6451 }
6452 
6453 /* Blocks in REGION_COPY array of length N_REGION were created by
6454    duplication of basic blocks.  Add phi node arguments for edges
6455    going from these blocks.  If E_COPY is not NULL, also add
6456    phi node arguments for its destination.*/
6457 
6458 void
6459 add_phi_args_after_copy (basic_block *region_copy, unsigned n_region,
6460 			 edge e_copy)
6461 {
6462   unsigned i;
6463 
6464   for (i = 0; i < n_region; i++)
6465     region_copy[i]->flags |= BB_DUPLICATED;
6466 
6467   for (i = 0; i < n_region; i++)
6468     add_phi_args_after_copy_bb (region_copy[i]);
6469   if (e_copy)
6470     add_phi_args_after_copy_edge (e_copy);
6471 
6472   for (i = 0; i < n_region; i++)
6473     region_copy[i]->flags &= ~BB_DUPLICATED;
6474 }
6475 
6476 /* Duplicates a REGION (set of N_REGION basic blocks) with just a single
6477    important exit edge EXIT.  By important we mean that no SSA name defined
6478    inside region is live over the other exit edges of the region.  All entry
6479    edges to the region must go to ENTRY->dest.  The edge ENTRY is redirected
6480    to the duplicate of the region.  Dominance and loop information is
6481    updated if UPDATE_DOMINANCE is true, but not the SSA web.  If
6482    UPDATE_DOMINANCE is false then we assume that the caller will update the
6483    dominance information after calling this function.  The new basic
6484    blocks are stored to REGION_COPY in the same order as they had in REGION,
6485    provided that REGION_COPY is not NULL.
6486    The function returns false if it is unable to copy the region,
6487    true otherwise.  */
6488 
6489 bool
6490 gimple_duplicate_sese_region (edge entry, edge exit,
6491 			    basic_block *region, unsigned n_region,
6492 			    basic_block *region_copy,
6493 			    bool update_dominance)
6494 {
6495   unsigned i;
6496   bool free_region_copy = false, copying_header = false;
6497   struct loop *loop = entry->dest->loop_father;
6498   edge exit_copy;
6499   vec<basic_block> doms = vNULL;
6500   edge redirected;
6501   profile_count total_count = profile_count::uninitialized ();
6502   profile_count entry_count = profile_count::uninitialized ();
6503 
6504   if (!can_copy_bbs_p (region, n_region))
6505     return false;
6506 
6507   /* Some sanity checking.  Note that we do not check for all possible
6508      missuses of the functions.  I.e. if you ask to copy something weird,
6509      it will work, but the state of structures probably will not be
6510      correct.  */
6511   for (i = 0; i < n_region; i++)
6512     {
6513       /* We do not handle subloops, i.e. all the blocks must belong to the
6514 	 same loop.  */
6515       if (region[i]->loop_father != loop)
6516 	return false;
6517 
6518       if (region[i] != entry->dest
6519 	  && region[i] == loop->header)
6520 	return false;
6521     }
6522 
6523   /* In case the function is used for loop header copying (which is the primary
6524      use), ensure that EXIT and its copy will be new latch and entry edges.  */
6525   if (loop->header == entry->dest)
6526     {
6527       copying_header = true;
6528 
6529       if (!dominated_by_p (CDI_DOMINATORS, loop->latch, exit->src))
6530 	return false;
6531 
6532       for (i = 0; i < n_region; i++)
6533 	if (region[i] != exit->src
6534 	    && dominated_by_p (CDI_DOMINATORS, region[i], exit->src))
6535 	  return false;
6536     }
6537 
6538   initialize_original_copy_tables ();
6539 
6540   if (copying_header)
6541     set_loop_copy (loop, loop_outer (loop));
6542   else
6543     set_loop_copy (loop, loop);
6544 
6545   if (!region_copy)
6546     {
6547       region_copy = XNEWVEC (basic_block, n_region);
6548       free_region_copy = true;
6549     }
6550 
6551   /* Record blocks outside the region that are dominated by something
6552      inside.  */
6553   if (update_dominance)
6554     {
6555       doms.create (0);
6556       doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
6557     }
6558 
6559   if (entry->dest->count.initialized_p ())
6560     {
6561       total_count = entry->dest->count;
6562       entry_count = entry->count ();
6563       /* Fix up corner cases, to avoid division by zero or creation of negative
6564 	 frequencies.  */
6565       if (entry_count > total_count)
6566 	entry_count = total_count;
6567     }
6568 
6569   copy_bbs (region, n_region, region_copy, &exit, 1, &exit_copy, loop,
6570 	    split_edge_bb_loc (entry), update_dominance);
6571   if (total_count.initialized_p () && entry_count.initialized_p ())
6572     {
6573       scale_bbs_frequencies_profile_count (region, n_region,
6574 				           total_count - entry_count,
6575 				           total_count);
6576       scale_bbs_frequencies_profile_count (region_copy, n_region, entry_count,
6577 				           total_count);
6578     }
6579 
6580   if (copying_header)
6581     {
6582       loop->header = exit->dest;
6583       loop->latch = exit->src;
6584     }
6585 
6586   /* Redirect the entry and add the phi node arguments.  */
6587   redirected = redirect_edge_and_branch (entry, get_bb_copy (entry->dest));
6588   gcc_assert (redirected != NULL);
6589   flush_pending_stmts (entry);
6590 
6591   /* Concerning updating of dominators:  We must recount dominators
6592      for entry block and its copy.  Anything that is outside of the
6593      region, but was dominated by something inside needs recounting as
6594      well.  */
6595   if (update_dominance)
6596     {
6597       set_immediate_dominator (CDI_DOMINATORS, entry->dest, entry->src);
6598       doms.safe_push (get_bb_original (entry->dest));
6599       iterate_fix_dominators (CDI_DOMINATORS, doms, false);
6600       doms.release ();
6601     }
6602 
6603   /* Add the other PHI node arguments.  */
6604   add_phi_args_after_copy (region_copy, n_region, NULL);
6605 
6606   if (free_region_copy)
6607     free (region_copy);
6608 
6609   free_original_copy_tables ();
6610   return true;
6611 }
6612 
6613 /* Checks if BB is part of the region defined by N_REGION BBS.  */
6614 static bool
6615 bb_part_of_region_p (basic_block bb, basic_block* bbs, unsigned n_region)
6616 {
6617   unsigned int n;
6618 
6619   for (n = 0; n < n_region; n++)
6620     {
6621      if (bb == bbs[n])
6622        return true;
6623     }
6624   return false;
6625 }
6626 
6627 /* Duplicates REGION consisting of N_REGION blocks.  The new blocks
6628    are stored to REGION_COPY in the same order in that they appear
6629    in REGION, if REGION_COPY is not NULL.  ENTRY is the entry to
6630    the region, EXIT an exit from it.  The condition guarding EXIT
6631    is moved to ENTRY.  Returns true if duplication succeeds, false
6632    otherwise.
6633 
6634    For example,
6635 
6636    some_code;
6637    if (cond)
6638      A;
6639    else
6640      B;
6641 
6642    is transformed to
6643 
6644    if (cond)
6645      {
6646        some_code;
6647        A;
6648      }
6649    else
6650      {
6651        some_code;
6652        B;
6653      }
6654 */
6655 
6656 bool
6657 gimple_duplicate_sese_tail (edge entry, edge exit,
6658 			  basic_block *region, unsigned n_region,
6659 			  basic_block *region_copy)
6660 {
6661   unsigned i;
6662   bool free_region_copy = false;
6663   struct loop *loop = exit->dest->loop_father;
6664   struct loop *orig_loop = entry->dest->loop_father;
6665   basic_block switch_bb, entry_bb, nentry_bb;
6666   vec<basic_block> doms;
6667   profile_count total_count = profile_count::uninitialized (),
6668 		exit_count = profile_count::uninitialized ();
6669   edge exits[2], nexits[2], e;
6670   gimple_stmt_iterator gsi;
6671   gimple *cond_stmt;
6672   edge sorig, snew;
6673   basic_block exit_bb;
6674   gphi_iterator psi;
6675   gphi *phi;
6676   tree def;
6677   struct loop *target, *aloop, *cloop;
6678 
6679   gcc_assert (EDGE_COUNT (exit->src->succs) == 2);
6680   exits[0] = exit;
6681   exits[1] = EDGE_SUCC (exit->src, EDGE_SUCC (exit->src, 0) == exit);
6682 
6683   if (!can_copy_bbs_p (region, n_region))
6684     return false;
6685 
6686   initialize_original_copy_tables ();
6687   set_loop_copy (orig_loop, loop);
6688 
6689   target= loop;
6690   for (aloop = orig_loop->inner; aloop; aloop = aloop->next)
6691     {
6692       if (bb_part_of_region_p (aloop->header, region, n_region))
6693 	{
6694 	  cloop = duplicate_loop (aloop, target);
6695 	  duplicate_subloops (aloop, cloop);
6696 	}
6697     }
6698 
6699   if (!region_copy)
6700     {
6701       region_copy = XNEWVEC (basic_block, n_region);
6702       free_region_copy = true;
6703     }
6704 
6705   gcc_assert (!need_ssa_update_p (cfun));
6706 
6707   /* Record blocks outside the region that are dominated by something
6708      inside.  */
6709   doms = get_dominated_by_region (CDI_DOMINATORS, region, n_region);
6710 
6711   total_count = exit->src->count;
6712   exit_count = exit->count ();
6713   /* Fix up corner cases, to avoid division by zero or creation of negative
6714      frequencies.  */
6715   if (exit_count > total_count)
6716     exit_count = total_count;
6717 
6718   copy_bbs (region, n_region, region_copy, exits, 2, nexits, orig_loop,
6719 	    split_edge_bb_loc (exit), true);
6720   if (total_count.initialized_p () && exit_count.initialized_p ())
6721     {
6722       scale_bbs_frequencies_profile_count (region, n_region,
6723 				           total_count - exit_count,
6724 				           total_count);
6725       scale_bbs_frequencies_profile_count (region_copy, n_region, exit_count,
6726 				           total_count);
6727     }
6728 
6729   /* Create the switch block, and put the exit condition to it.  */
6730   entry_bb = entry->dest;
6731   nentry_bb = get_bb_copy (entry_bb);
6732   if (!last_stmt (entry->src)
6733       || !stmt_ends_bb_p (last_stmt (entry->src)))
6734     switch_bb = entry->src;
6735   else
6736     switch_bb = split_edge (entry);
6737   set_immediate_dominator (CDI_DOMINATORS, nentry_bb, switch_bb);
6738 
6739   gsi = gsi_last_bb (switch_bb);
6740   cond_stmt = last_stmt (exit->src);
6741   gcc_assert (gimple_code (cond_stmt) == GIMPLE_COND);
6742   cond_stmt = gimple_copy (cond_stmt);
6743 
6744   gsi_insert_after (&gsi, cond_stmt, GSI_NEW_STMT);
6745 
6746   sorig = single_succ_edge (switch_bb);
6747   sorig->flags = exits[1]->flags;
6748   sorig->probability = exits[1]->probability;
6749   snew = make_edge (switch_bb, nentry_bb, exits[0]->flags);
6750   snew->probability = exits[0]->probability;
6751 
6752 
6753   /* Register the new edge from SWITCH_BB in loop exit lists.  */
6754   rescan_loop_exit (snew, true, false);
6755 
6756   /* Add the PHI node arguments.  */
6757   add_phi_args_after_copy (region_copy, n_region, snew);
6758 
6759   /* Get rid of now superfluous conditions and associated edges (and phi node
6760      arguments).  */
6761   exit_bb = exit->dest;
6762 
6763   e = redirect_edge_and_branch (exits[0], exits[1]->dest);
6764   PENDING_STMT (e) = NULL;
6765 
6766   /* The latch of ORIG_LOOP was copied, and so was the backedge
6767      to the original header.  We redirect this backedge to EXIT_BB.  */
6768   for (i = 0; i < n_region; i++)
6769     if (get_bb_original (region_copy[i]) == orig_loop->latch)
6770       {
6771 	gcc_assert (single_succ_edge (region_copy[i]));
6772 	e = redirect_edge_and_branch (single_succ_edge (region_copy[i]), exit_bb);
6773 	PENDING_STMT (e) = NULL;
6774 	for (psi = gsi_start_phis (exit_bb);
6775 	     !gsi_end_p (psi);
6776 	     gsi_next (&psi))
6777 	  {
6778 	    phi = psi.phi ();
6779 	    def = PHI_ARG_DEF (phi, nexits[0]->dest_idx);
6780 	    add_phi_arg (phi, def, e, gimple_phi_arg_location_from_edge (phi, e));
6781 	  }
6782       }
6783   e = redirect_edge_and_branch (nexits[1], nexits[0]->dest);
6784   PENDING_STMT (e) = NULL;
6785 
6786   /* Anything that is outside of the region, but was dominated by something
6787      inside needs to update dominance info.  */
6788   iterate_fix_dominators (CDI_DOMINATORS, doms, false);
6789   doms.release ();
6790   /* Update the SSA web.  */
6791   update_ssa (TODO_update_ssa);
6792 
6793   if (free_region_copy)
6794     free (region_copy);
6795 
6796   free_original_copy_tables ();
6797   return true;
6798 }
6799 
6800 /* Add all the blocks dominated by ENTRY to the array BBS_P.  Stop
6801    adding blocks when the dominator traversal reaches EXIT.  This
6802    function silently assumes that ENTRY strictly dominates EXIT.  */
6803 
6804 void
6805 gather_blocks_in_sese_region (basic_block entry, basic_block exit,
6806 			      vec<basic_block> *bbs_p)
6807 {
6808   basic_block son;
6809 
6810   for (son = first_dom_son (CDI_DOMINATORS, entry);
6811        son;
6812        son = next_dom_son (CDI_DOMINATORS, son))
6813     {
6814       bbs_p->safe_push (son);
6815       if (son != exit)
6816 	gather_blocks_in_sese_region (son, exit, bbs_p);
6817     }
6818 }
6819 
6820 /* Replaces *TP with a duplicate (belonging to function TO_CONTEXT).
6821    The duplicates are recorded in VARS_MAP.  */
6822 
6823 static void
6824 replace_by_duplicate_decl (tree *tp, hash_map<tree, tree> *vars_map,
6825 			   tree to_context)
6826 {
6827   tree t = *tp, new_t;
6828   struct function *f = DECL_STRUCT_FUNCTION (to_context);
6829 
6830   if (DECL_CONTEXT (t) == to_context)
6831     return;
6832 
6833   bool existed;
6834   tree &loc = vars_map->get_or_insert (t, &existed);
6835 
6836   if (!existed)
6837     {
6838       if (SSA_VAR_P (t))
6839 	{
6840 	  new_t = copy_var_decl (t, DECL_NAME (t), TREE_TYPE (t));
6841 	  add_local_decl (f, new_t);
6842 	}
6843       else
6844 	{
6845 	  gcc_assert (TREE_CODE (t) == CONST_DECL);
6846 	  new_t = copy_node (t);
6847 	}
6848       DECL_CONTEXT (new_t) = to_context;
6849 
6850       loc = new_t;
6851     }
6852   else
6853     new_t = loc;
6854 
6855   *tp = new_t;
6856 }
6857 
6858 
6859 /* Creates an ssa name in TO_CONTEXT equivalent to NAME.
6860    VARS_MAP maps old ssa names and var_decls to the new ones.  */
6861 
6862 static tree
6863 replace_ssa_name (tree name, hash_map<tree, tree> *vars_map,
6864 		  tree to_context)
6865 {
6866   tree new_name;
6867 
6868   gcc_assert (!virtual_operand_p (name));
6869 
6870   tree *loc = vars_map->get (name);
6871 
6872   if (!loc)
6873     {
6874       tree decl = SSA_NAME_VAR (name);
6875       if (decl)
6876 	{
6877 	  gcc_assert (!SSA_NAME_IS_DEFAULT_DEF (name));
6878 	  replace_by_duplicate_decl (&decl, vars_map, to_context);
6879 	  new_name = make_ssa_name_fn (DECL_STRUCT_FUNCTION (to_context),
6880 				       decl, SSA_NAME_DEF_STMT (name));
6881 	}
6882       else
6883 	new_name = copy_ssa_name_fn (DECL_STRUCT_FUNCTION (to_context),
6884 				     name, SSA_NAME_DEF_STMT (name));
6885 
6886       /* Now that we've used the def stmt to define new_name, make sure it
6887 	 doesn't define name anymore.  */
6888       SSA_NAME_DEF_STMT (name) = NULL;
6889 
6890       vars_map->put (name, new_name);
6891     }
6892   else
6893     new_name = *loc;
6894 
6895   return new_name;
6896 }
6897 
6898 struct move_stmt_d
6899 {
6900   tree orig_block;
6901   tree new_block;
6902   tree from_context;
6903   tree to_context;
6904   hash_map<tree, tree> *vars_map;
6905   htab_t new_label_map;
6906   hash_map<void *, void *> *eh_map;
6907   bool remap_decls_p;
6908 };
6909 
6910 /* Helper for move_block_to_fn.  Set TREE_BLOCK in every expression
6911    contained in *TP if it has been ORIG_BLOCK previously and change the
6912    DECL_CONTEXT of every local variable referenced in *TP.  */
6913 
6914 static tree
6915 move_stmt_op (tree *tp, int *walk_subtrees, void *data)
6916 {
6917   struct walk_stmt_info *wi = (struct walk_stmt_info *) data;
6918   struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
6919   tree t = *tp;
6920 
6921   if (EXPR_P (t))
6922     {
6923       tree block = TREE_BLOCK (t);
6924       if (block == NULL_TREE)
6925 	;
6926       else if (block == p->orig_block
6927 	       || p->orig_block == NULL_TREE)
6928 	TREE_SET_BLOCK (t, p->new_block);
6929       else if (flag_checking)
6930 	{
6931 	  while (block && TREE_CODE (block) == BLOCK && block != p->orig_block)
6932 	    block = BLOCK_SUPERCONTEXT (block);
6933 	  gcc_assert (block == p->orig_block);
6934 	}
6935     }
6936   else if (DECL_P (t) || TREE_CODE (t) == SSA_NAME)
6937     {
6938       if (TREE_CODE (t) == SSA_NAME)
6939 	*tp = replace_ssa_name (t, p->vars_map, p->to_context);
6940       else if (TREE_CODE (t) == PARM_DECL
6941 	       && gimple_in_ssa_p (cfun))
6942 	*tp = *(p->vars_map->get (t));
6943       else if (TREE_CODE (t) == LABEL_DECL)
6944 	{
6945 	  if (p->new_label_map)
6946 	    {
6947 	      struct tree_map in, *out;
6948 	      in.base.from = t;
6949 	      out = (struct tree_map *)
6950 		htab_find_with_hash (p->new_label_map, &in, DECL_UID (t));
6951 	      if (out)
6952 		*tp = t = out->to;
6953 	    }
6954 
6955 	  /* For FORCED_LABELs we can end up with references from other
6956 	     functions if some SESE regions are outlined.  It is UB to
6957 	     jump in between them, but they could be used just for printing
6958 	     addresses etc.  In that case, DECL_CONTEXT on the label should
6959 	     be the function containing the glabel stmt with that LABEL_DECL,
6960 	     rather than whatever function a reference to the label was seen
6961 	     last time.  */
6962 	  if (!FORCED_LABEL (t) && !DECL_NONLOCAL (t))
6963 	    DECL_CONTEXT (t) = p->to_context;
6964 	}
6965       else if (p->remap_decls_p)
6966 	{
6967 	  /* Replace T with its duplicate.  T should no longer appear in the
6968 	     parent function, so this looks wasteful; however, it may appear
6969 	     in referenced_vars, and more importantly, as virtual operands of
6970 	     statements, and in alias lists of other variables.  It would be
6971 	     quite difficult to expunge it from all those places.  ??? It might
6972 	     suffice to do this for addressable variables.  */
6973 	  if ((VAR_P (t) && !is_global_var (t))
6974 	      || TREE_CODE (t) == CONST_DECL)
6975 	    replace_by_duplicate_decl (tp, p->vars_map, p->to_context);
6976 	}
6977       *walk_subtrees = 0;
6978     }
6979   else if (TYPE_P (t))
6980     *walk_subtrees = 0;
6981 
6982   return NULL_TREE;
6983 }
6984 
6985 /* Helper for move_stmt_r.  Given an EH region number for the source
6986    function, map that to the duplicate EH regio number in the dest.  */
6987 
6988 static int
6989 move_stmt_eh_region_nr (int old_nr, struct move_stmt_d *p)
6990 {
6991   eh_region old_r, new_r;
6992 
6993   old_r = get_eh_region_from_number (old_nr);
6994   new_r = static_cast<eh_region> (*p->eh_map->get (old_r));
6995 
6996   return new_r->index;
6997 }
6998 
6999 /* Similar, but operate on INTEGER_CSTs.  */
7000 
7001 static tree
7002 move_stmt_eh_region_tree_nr (tree old_t_nr, struct move_stmt_d *p)
7003 {
7004   int old_nr, new_nr;
7005 
7006   old_nr = tree_to_shwi (old_t_nr);
7007   new_nr = move_stmt_eh_region_nr (old_nr, p);
7008 
7009   return build_int_cst (integer_type_node, new_nr);
7010 }
7011 
7012 /* Like move_stmt_op, but for gimple statements.
7013 
7014    Helper for move_block_to_fn.  Set GIMPLE_BLOCK in every expression
7015    contained in the current statement in *GSI_P and change the
7016    DECL_CONTEXT of every local variable referenced in the current
7017    statement.  */
7018 
7019 static tree
7020 move_stmt_r (gimple_stmt_iterator *gsi_p, bool *handled_ops_p,
7021 	     struct walk_stmt_info *wi)
7022 {
7023   struct move_stmt_d *p = (struct move_stmt_d *) wi->info;
7024   gimple *stmt = gsi_stmt (*gsi_p);
7025   tree block = gimple_block (stmt);
7026 
7027   if (block == p->orig_block
7028       || (p->orig_block == NULL_TREE
7029 	  && block != NULL_TREE))
7030     gimple_set_block (stmt, p->new_block);
7031 
7032   switch (gimple_code (stmt))
7033     {
7034     case GIMPLE_CALL:
7035       /* Remap the region numbers for __builtin_eh_{pointer,filter}.  */
7036       {
7037 	tree r, fndecl = gimple_call_fndecl (stmt);
7038 	if (fndecl && DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL)
7039 	  switch (DECL_FUNCTION_CODE (fndecl))
7040 	    {
7041 	    case BUILT_IN_EH_COPY_VALUES:
7042 	      r = gimple_call_arg (stmt, 1);
7043 	      r = move_stmt_eh_region_tree_nr (r, p);
7044 	      gimple_call_set_arg (stmt, 1, r);
7045 	      /* FALLTHRU */
7046 
7047 	    case BUILT_IN_EH_POINTER:
7048 	    case BUILT_IN_EH_FILTER:
7049 	      r = gimple_call_arg (stmt, 0);
7050 	      r = move_stmt_eh_region_tree_nr (r, p);
7051 	      gimple_call_set_arg (stmt, 0, r);
7052 	      break;
7053 
7054 	    default:
7055 	      break;
7056 	    }
7057       }
7058       break;
7059 
7060     case GIMPLE_RESX:
7061       {
7062 	gresx *resx_stmt = as_a <gresx *> (stmt);
7063 	int r = gimple_resx_region (resx_stmt);
7064 	r = move_stmt_eh_region_nr (r, p);
7065 	gimple_resx_set_region (resx_stmt, r);
7066       }
7067       break;
7068 
7069     case GIMPLE_EH_DISPATCH:
7070       {
7071 	geh_dispatch *eh_dispatch_stmt = as_a <geh_dispatch *> (stmt);
7072 	int r = gimple_eh_dispatch_region (eh_dispatch_stmt);
7073 	r = move_stmt_eh_region_nr (r, p);
7074 	gimple_eh_dispatch_set_region (eh_dispatch_stmt, r);
7075       }
7076       break;
7077 
7078     case GIMPLE_OMP_RETURN:
7079     case GIMPLE_OMP_CONTINUE:
7080       break;
7081 
7082     case GIMPLE_LABEL:
7083       {
7084 	/* For FORCED_LABEL, move_stmt_op doesn't adjust DECL_CONTEXT,
7085 	   so that such labels can be referenced from other regions.
7086 	   Make sure to update it when seeing a GIMPLE_LABEL though,
7087 	   that is the owner of the label.  */
7088 	walk_gimple_op (stmt, move_stmt_op, wi);
7089 	*handled_ops_p = true;
7090 	tree label = gimple_label_label (as_a <glabel *> (stmt));
7091 	if (FORCED_LABEL (label) || DECL_NONLOCAL (label))
7092 	  DECL_CONTEXT (label) = p->to_context;
7093       }
7094       break;
7095 
7096     default:
7097       if (is_gimple_omp (stmt))
7098 	{
7099 	  /* Do not remap variables inside OMP directives.  Variables
7100 	     referenced in clauses and directive header belong to the
7101 	     parent function and should not be moved into the child
7102 	     function.  */
7103 	  bool save_remap_decls_p = p->remap_decls_p;
7104 	  p->remap_decls_p = false;
7105 	  *handled_ops_p = true;
7106 
7107 	  walk_gimple_seq_mod (gimple_omp_body_ptr (stmt), move_stmt_r,
7108 			       move_stmt_op, wi);
7109 
7110 	  p->remap_decls_p = save_remap_decls_p;
7111 	}
7112       break;
7113     }
7114 
7115   return NULL_TREE;
7116 }
7117 
7118 /* Move basic block BB from function CFUN to function DEST_FN.  The
7119    block is moved out of the original linked list and placed after
7120    block AFTER in the new list.  Also, the block is removed from the
7121    original array of blocks and placed in DEST_FN's array of blocks.
7122    If UPDATE_EDGE_COUNT_P is true, the edge counts on both CFGs is
7123    updated to reflect the moved edges.
7124 
7125    The local variables are remapped to new instances, VARS_MAP is used
7126    to record the mapping.  */
7127 
7128 static void
7129 move_block_to_fn (struct function *dest_cfun, basic_block bb,
7130 		  basic_block after, bool update_edge_count_p,
7131 		  struct move_stmt_d *d)
7132 {
7133   struct control_flow_graph *cfg;
7134   edge_iterator ei;
7135   edge e;
7136   gimple_stmt_iterator si;
7137   unsigned old_len, new_len;
7138 
7139   /* Remove BB from dominance structures.  */
7140   delete_from_dominance_info (CDI_DOMINATORS, bb);
7141 
7142   /* Move BB from its current loop to the copy in the new function.  */
7143   if (current_loops)
7144     {
7145       struct loop *new_loop = (struct loop *)bb->loop_father->aux;
7146       if (new_loop)
7147 	bb->loop_father = new_loop;
7148     }
7149 
7150   /* Link BB to the new linked list.  */
7151   move_block_after (bb, after);
7152 
7153   /* Update the edge count in the corresponding flowgraphs.  */
7154   if (update_edge_count_p)
7155     FOR_EACH_EDGE (e, ei, bb->succs)
7156       {
7157 	cfun->cfg->x_n_edges--;
7158 	dest_cfun->cfg->x_n_edges++;
7159       }
7160 
7161   /* Remove BB from the original basic block array.  */
7162   (*cfun->cfg->x_basic_block_info)[bb->index] = NULL;
7163   cfun->cfg->x_n_basic_blocks--;
7164 
7165   /* Grow DEST_CFUN's basic block array if needed.  */
7166   cfg = dest_cfun->cfg;
7167   cfg->x_n_basic_blocks++;
7168   if (bb->index >= cfg->x_last_basic_block)
7169     cfg->x_last_basic_block = bb->index + 1;
7170 
7171   old_len = vec_safe_length (cfg->x_basic_block_info);
7172   if ((unsigned) cfg->x_last_basic_block >= old_len)
7173     {
7174       new_len = cfg->x_last_basic_block + (cfg->x_last_basic_block + 3) / 4;
7175       vec_safe_grow_cleared (cfg->x_basic_block_info, new_len);
7176     }
7177 
7178   (*cfg->x_basic_block_info)[bb->index] = bb;
7179 
7180   /* Remap the variables in phi nodes.  */
7181   for (gphi_iterator psi = gsi_start_phis (bb);
7182        !gsi_end_p (psi); )
7183     {
7184       gphi *phi = psi.phi ();
7185       use_operand_p use;
7186       tree op = PHI_RESULT (phi);
7187       ssa_op_iter oi;
7188       unsigned i;
7189 
7190       if (virtual_operand_p (op))
7191 	{
7192 	  /* Remove the phi nodes for virtual operands (alias analysis will be
7193 	     run for the new function, anyway).  */
7194           remove_phi_node (&psi, true);
7195 	  continue;
7196 	}
7197 
7198       SET_PHI_RESULT (phi,
7199 		      replace_ssa_name (op, d->vars_map, dest_cfun->decl));
7200       FOR_EACH_PHI_ARG (use, phi, oi, SSA_OP_USE)
7201 	{
7202 	  op = USE_FROM_PTR (use);
7203 	  if (TREE_CODE (op) == SSA_NAME)
7204 	    SET_USE (use, replace_ssa_name (op, d->vars_map, dest_cfun->decl));
7205 	}
7206 
7207       for (i = 0; i < EDGE_COUNT (bb->preds); i++)
7208 	{
7209 	  location_t locus = gimple_phi_arg_location (phi, i);
7210 	  tree block = LOCATION_BLOCK (locus);
7211 
7212 	  if (locus == UNKNOWN_LOCATION)
7213 	    continue;
7214 	  if (d->orig_block == NULL_TREE || block == d->orig_block)
7215 	    {
7216 	      locus = set_block (locus, d->new_block);
7217 	      gimple_phi_arg_set_location (phi, i, locus);
7218 	    }
7219 	}
7220 
7221       gsi_next (&psi);
7222     }
7223 
7224   for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
7225     {
7226       gimple *stmt = gsi_stmt (si);
7227       struct walk_stmt_info wi;
7228 
7229       memset (&wi, 0, sizeof (wi));
7230       wi.info = d;
7231       walk_gimple_stmt (&si, move_stmt_r, move_stmt_op, &wi);
7232 
7233       if (glabel *label_stmt = dyn_cast <glabel *> (stmt))
7234 	{
7235 	  tree label = gimple_label_label (label_stmt);
7236 	  int uid = LABEL_DECL_UID (label);
7237 
7238 	  gcc_assert (uid > -1);
7239 
7240 	  old_len = vec_safe_length (cfg->x_label_to_block_map);
7241 	  if (old_len <= (unsigned) uid)
7242 	    {
7243 	      new_len = 3 * uid / 2 + 1;
7244 	      vec_safe_grow_cleared (cfg->x_label_to_block_map, new_len);
7245 	    }
7246 
7247 	  (*cfg->x_label_to_block_map)[uid] = bb;
7248 	  (*cfun->cfg->x_label_to_block_map)[uid] = NULL;
7249 
7250 	  gcc_assert (DECL_CONTEXT (label) == dest_cfun->decl);
7251 
7252 	  if (uid >= dest_cfun->cfg->last_label_uid)
7253 	    dest_cfun->cfg->last_label_uid = uid + 1;
7254 	}
7255 
7256       maybe_duplicate_eh_stmt_fn (dest_cfun, stmt, cfun, stmt, d->eh_map, 0);
7257       remove_stmt_from_eh_lp_fn (cfun, stmt);
7258 
7259       gimple_duplicate_stmt_histograms (dest_cfun, stmt, cfun, stmt);
7260       gimple_remove_stmt_histograms (cfun, stmt);
7261 
7262       /* We cannot leave any operands allocated from the operand caches of
7263 	 the current function.  */
7264       free_stmt_operands (cfun, stmt);
7265       push_cfun (dest_cfun);
7266       update_stmt (stmt);
7267       pop_cfun ();
7268     }
7269 
7270   FOR_EACH_EDGE (e, ei, bb->succs)
7271     if (e->goto_locus != UNKNOWN_LOCATION)
7272       {
7273 	tree block = LOCATION_BLOCK (e->goto_locus);
7274 	if (d->orig_block == NULL_TREE
7275 	    || block == d->orig_block)
7276 	  e->goto_locus = set_block (e->goto_locus, d->new_block);
7277       }
7278 }
7279 
7280 /* Examine the statements in BB (which is in SRC_CFUN); find and return
7281    the outermost EH region.  Use REGION as the incoming base EH region.  */
7282 
7283 static eh_region
7284 find_outermost_region_in_block (struct function *src_cfun,
7285 				basic_block bb, eh_region region)
7286 {
7287   gimple_stmt_iterator si;
7288 
7289   for (si = gsi_start_bb (bb); !gsi_end_p (si); gsi_next (&si))
7290     {
7291       gimple *stmt = gsi_stmt (si);
7292       eh_region stmt_region;
7293       int lp_nr;
7294 
7295       lp_nr = lookup_stmt_eh_lp_fn (src_cfun, stmt);
7296       stmt_region = get_eh_region_from_lp_number_fn (src_cfun, lp_nr);
7297       if (stmt_region)
7298 	{
7299 	  if (region == NULL)
7300 	    region = stmt_region;
7301 	  else if (stmt_region != region)
7302 	    {
7303 	      region = eh_region_outermost (src_cfun, stmt_region, region);
7304 	      gcc_assert (region != NULL);
7305 	    }
7306 	}
7307     }
7308 
7309   return region;
7310 }
7311 
7312 static tree
7313 new_label_mapper (tree decl, void *data)
7314 {
7315   htab_t hash = (htab_t) data;
7316   struct tree_map *m;
7317   void **slot;
7318 
7319   gcc_assert (TREE_CODE (decl) == LABEL_DECL);
7320 
7321   m = XNEW (struct tree_map);
7322   m->hash = DECL_UID (decl);
7323   m->base.from = decl;
7324   m->to = create_artificial_label (UNKNOWN_LOCATION);
7325   LABEL_DECL_UID (m->to) = LABEL_DECL_UID (decl);
7326   if (LABEL_DECL_UID (m->to) >= cfun->cfg->last_label_uid)
7327     cfun->cfg->last_label_uid = LABEL_DECL_UID (m->to) + 1;
7328 
7329   slot = htab_find_slot_with_hash (hash, m, m->hash, INSERT);
7330   gcc_assert (*slot == NULL);
7331 
7332   *slot = m;
7333 
7334   return m->to;
7335 }
7336 
7337 /* Tree walker to replace the decls used inside value expressions by
7338    duplicates.  */
7339 
7340 static tree
7341 replace_block_vars_by_duplicates_1 (tree *tp, int *walk_subtrees, void *data)
7342 {
7343   struct replace_decls_d *rd = (struct replace_decls_d *)data;
7344 
7345   switch (TREE_CODE (*tp))
7346     {
7347     case VAR_DECL:
7348     case PARM_DECL:
7349     case RESULT_DECL:
7350       replace_by_duplicate_decl (tp, rd->vars_map, rd->to_context);
7351       break;
7352     default:
7353       break;
7354     }
7355 
7356   if (IS_TYPE_OR_DECL_P (*tp))
7357     *walk_subtrees = false;
7358 
7359   return NULL;
7360 }
7361 
7362 /* Change DECL_CONTEXT of all BLOCK_VARS in block, including
7363    subblocks.  */
7364 
7365 static void
7366 replace_block_vars_by_duplicates (tree block, hash_map<tree, tree> *vars_map,
7367 				  tree to_context)
7368 {
7369   tree *tp, t;
7370 
7371   for (tp = &BLOCK_VARS (block); *tp; tp = &DECL_CHAIN (*tp))
7372     {
7373       t = *tp;
7374       if (!VAR_P (t) && TREE_CODE (t) != CONST_DECL)
7375 	continue;
7376       replace_by_duplicate_decl (&t, vars_map, to_context);
7377       if (t != *tp)
7378 	{
7379 	  if (VAR_P (*tp) && DECL_HAS_VALUE_EXPR_P (*tp))
7380 	    {
7381 	      tree x = DECL_VALUE_EXPR (*tp);
7382 	      struct replace_decls_d rd = { vars_map, to_context };
7383 	      unshare_expr (x);
7384 	      walk_tree (&x, replace_block_vars_by_duplicates_1, &rd, NULL);
7385 	      SET_DECL_VALUE_EXPR (t, x);
7386 	      DECL_HAS_VALUE_EXPR_P (t) = 1;
7387 	    }
7388 	  DECL_CHAIN (t) = DECL_CHAIN (*tp);
7389 	  *tp = t;
7390 	}
7391     }
7392 
7393   for (block = BLOCK_SUBBLOCKS (block); block; block = BLOCK_CHAIN (block))
7394     replace_block_vars_by_duplicates (block, vars_map, to_context);
7395 }
7396 
7397 /* Fixup the loop arrays and numbers after moving LOOP and its subloops
7398    from FN1 to FN2.  */
7399 
7400 static void
7401 fixup_loop_arrays_after_move (struct function *fn1, struct function *fn2,
7402 			      struct loop *loop)
7403 {
7404   /* Discard it from the old loop array.  */
7405   (*get_loops (fn1))[loop->num] = NULL;
7406 
7407   /* Place it in the new loop array, assigning it a new number.  */
7408   loop->num = number_of_loops (fn2);
7409   vec_safe_push (loops_for_fn (fn2)->larray, loop);
7410 
7411   /* Recurse to children.  */
7412   for (loop = loop->inner; loop; loop = loop->next)
7413     fixup_loop_arrays_after_move (fn1, fn2, loop);
7414 }
7415 
7416 /* Verify that the blocks in BBS_P are a single-entry, single-exit region
7417    delimited by ENTRY_BB and EXIT_BB, possibly containing noreturn blocks.  */
7418 
7419 DEBUG_FUNCTION void
7420 verify_sese (basic_block entry, basic_block exit, vec<basic_block> *bbs_p)
7421 {
7422   basic_block bb;
7423   edge_iterator ei;
7424   edge e;
7425   bitmap bbs = BITMAP_ALLOC (NULL);
7426   int i;
7427 
7428   gcc_assert (entry != NULL);
7429   gcc_assert (entry != exit);
7430   gcc_assert (bbs_p != NULL);
7431 
7432   gcc_assert (bbs_p->length () > 0);
7433 
7434   FOR_EACH_VEC_ELT (*bbs_p, i, bb)
7435     bitmap_set_bit (bbs, bb->index);
7436 
7437   gcc_assert (bitmap_bit_p (bbs, entry->index));
7438   gcc_assert (exit == NULL || bitmap_bit_p (bbs, exit->index));
7439 
7440   FOR_EACH_VEC_ELT (*bbs_p, i, bb)
7441     {
7442       if (bb == entry)
7443 	{
7444 	  gcc_assert (single_pred_p (entry));
7445 	  gcc_assert (!bitmap_bit_p (bbs, single_pred (entry)->index));
7446 	}
7447       else
7448 	for (ei = ei_start (bb->preds); !ei_end_p (ei); ei_next (&ei))
7449 	  {
7450 	    e = ei_edge (ei);
7451 	    gcc_assert (bitmap_bit_p (bbs, e->src->index));
7452 	  }
7453 
7454       if (bb == exit)
7455 	{
7456 	  gcc_assert (single_succ_p (exit));
7457 	  gcc_assert (!bitmap_bit_p (bbs, single_succ (exit)->index));
7458 	}
7459       else
7460 	for (ei = ei_start (bb->succs); !ei_end_p (ei); ei_next (&ei))
7461 	  {
7462 	    e = ei_edge (ei);
7463 	    gcc_assert (bitmap_bit_p (bbs, e->dest->index));
7464 	  }
7465     }
7466 
7467   BITMAP_FREE (bbs);
7468 }
7469 
7470 /* If FROM is an SSA_NAME, mark the version in bitmap DATA.  */
7471 
7472 bool
7473 gather_ssa_name_hash_map_from (tree const &from, tree const &, void *data)
7474 {
7475   bitmap release_names = (bitmap)data;
7476 
7477   if (TREE_CODE (from) != SSA_NAME)
7478     return true;
7479 
7480   bitmap_set_bit (release_names, SSA_NAME_VERSION (from));
7481   return true;
7482 }
7483 
7484 /* Return LOOP_DIST_ALIAS call if present in BB.  */
7485 
7486 static gimple *
7487 find_loop_dist_alias (basic_block bb)
7488 {
7489   gimple *g = last_stmt (bb);
7490   if (g == NULL || gimple_code (g) != GIMPLE_COND)
7491     return NULL;
7492 
7493   gimple_stmt_iterator gsi = gsi_for_stmt (g);
7494   gsi_prev (&gsi);
7495   if (gsi_end_p (gsi))
7496     return NULL;
7497 
7498   g = gsi_stmt (gsi);
7499   if (gimple_call_internal_p (g, IFN_LOOP_DIST_ALIAS))
7500     return g;
7501   return NULL;
7502 }
7503 
7504 /* Fold loop internal call G like IFN_LOOP_VECTORIZED/IFN_LOOP_DIST_ALIAS
7505    to VALUE and update any immediate uses of it's LHS.  */
7506 
7507 void
7508 fold_loop_internal_call (gimple *g, tree value)
7509 {
7510   tree lhs = gimple_call_lhs (g);
7511   use_operand_p use_p;
7512   imm_use_iterator iter;
7513   gimple *use_stmt;
7514   gimple_stmt_iterator gsi = gsi_for_stmt (g);
7515 
7516   update_call_from_tree (&gsi, value);
7517   FOR_EACH_IMM_USE_STMT (use_stmt, iter, lhs)
7518     {
7519       FOR_EACH_IMM_USE_ON_STMT (use_p, iter)
7520 	SET_USE (use_p, value);
7521       update_stmt (use_stmt);
7522     }
7523 }
7524 
7525 /* Move a single-entry, single-exit region delimited by ENTRY_BB and
7526    EXIT_BB to function DEST_CFUN.  The whole region is replaced by a
7527    single basic block in the original CFG and the new basic block is
7528    returned.  DEST_CFUN must not have a CFG yet.
7529 
7530    Note that the region need not be a pure SESE region.  Blocks inside
7531    the region may contain calls to abort/exit.  The only restriction
7532    is that ENTRY_BB should be the only entry point and it must
7533    dominate EXIT_BB.
7534 
7535    Change TREE_BLOCK of all statements in ORIG_BLOCK to the new
7536    functions outermost BLOCK, move all subblocks of ORIG_BLOCK
7537    to the new function.
7538 
7539    All local variables referenced in the region are assumed to be in
7540    the corresponding BLOCK_VARS and unexpanded variable lists
7541    associated with DEST_CFUN.
7542 
7543    TODO: investigate whether we can reuse gimple_duplicate_sese_region to
7544    reimplement move_sese_region_to_fn by duplicating the region rather than
7545    moving it.  */
7546 
7547 basic_block
7548 move_sese_region_to_fn (struct function *dest_cfun, basic_block entry_bb,
7549 		        basic_block exit_bb, tree orig_block)
7550 {
7551   vec<basic_block> bbs, dom_bbs;
7552   basic_block dom_entry = get_immediate_dominator (CDI_DOMINATORS, entry_bb);
7553   basic_block after, bb, *entry_pred, *exit_succ, abb;
7554   struct function *saved_cfun = cfun;
7555   int *entry_flag, *exit_flag;
7556   profile_probability *entry_prob, *exit_prob;
7557   unsigned i, num_entry_edges, num_exit_edges, num_nodes;
7558   edge e;
7559   edge_iterator ei;
7560   htab_t new_label_map;
7561   hash_map<void *, void *> *eh_map;
7562   struct loop *loop = entry_bb->loop_father;
7563   struct loop *loop0 = get_loop (saved_cfun, 0);
7564   struct move_stmt_d d;
7565 
7566   /* If ENTRY does not strictly dominate EXIT, this cannot be an SESE
7567      region.  */
7568   gcc_assert (entry_bb != exit_bb
7569               && (!exit_bb
7570 		  || dominated_by_p (CDI_DOMINATORS, exit_bb, entry_bb)));
7571 
7572   /* Collect all the blocks in the region.  Manually add ENTRY_BB
7573      because it won't be added by dfs_enumerate_from.  */
7574   bbs.create (0);
7575   bbs.safe_push (entry_bb);
7576   gather_blocks_in_sese_region (entry_bb, exit_bb, &bbs);
7577 
7578   if (flag_checking)
7579     verify_sese (entry_bb, exit_bb, &bbs);
7580 
7581   /* The blocks that used to be dominated by something in BBS will now be
7582      dominated by the new block.  */
7583   dom_bbs = get_dominated_by_region (CDI_DOMINATORS,
7584 				     bbs.address (),
7585 				     bbs.length ());
7586 
7587   /* Detach ENTRY_BB and EXIT_BB from CFUN->CFG.  We need to remember
7588      the predecessor edges to ENTRY_BB and the successor edges to
7589      EXIT_BB so that we can re-attach them to the new basic block that
7590      will replace the region.  */
7591   num_entry_edges = EDGE_COUNT (entry_bb->preds);
7592   entry_pred = XNEWVEC (basic_block, num_entry_edges);
7593   entry_flag = XNEWVEC (int, num_entry_edges);
7594   entry_prob = XNEWVEC (profile_probability, num_entry_edges);
7595   i = 0;
7596   for (ei = ei_start (entry_bb->preds); (e = ei_safe_edge (ei)) != NULL;)
7597     {
7598       entry_prob[i] = e->probability;
7599       entry_flag[i] = e->flags;
7600       entry_pred[i++] = e->src;
7601       remove_edge (e);
7602     }
7603 
7604   if (exit_bb)
7605     {
7606       num_exit_edges = EDGE_COUNT (exit_bb->succs);
7607       exit_succ = XNEWVEC (basic_block, num_exit_edges);
7608       exit_flag = XNEWVEC (int, num_exit_edges);
7609       exit_prob = XNEWVEC (profile_probability, num_exit_edges);
7610       i = 0;
7611       for (ei = ei_start (exit_bb->succs); (e = ei_safe_edge (ei)) != NULL;)
7612 	{
7613 	  exit_prob[i] = e->probability;
7614 	  exit_flag[i] = e->flags;
7615 	  exit_succ[i++] = e->dest;
7616 	  remove_edge (e);
7617 	}
7618     }
7619   else
7620     {
7621       num_exit_edges = 0;
7622       exit_succ = NULL;
7623       exit_flag = NULL;
7624       exit_prob = NULL;
7625     }
7626 
7627   /* Switch context to the child function to initialize DEST_FN's CFG.  */
7628   gcc_assert (dest_cfun->cfg == NULL);
7629   push_cfun (dest_cfun);
7630 
7631   init_empty_tree_cfg ();
7632 
7633   /* Initialize EH information for the new function.  */
7634   eh_map = NULL;
7635   new_label_map = NULL;
7636   if (saved_cfun->eh)
7637     {
7638       eh_region region = NULL;
7639 
7640       FOR_EACH_VEC_ELT (bbs, i, bb)
7641 	region = find_outermost_region_in_block (saved_cfun, bb, region);
7642 
7643       init_eh_for_function ();
7644       if (region != NULL)
7645 	{
7646 	  new_label_map = htab_create (17, tree_map_hash, tree_map_eq, free);
7647 	  eh_map = duplicate_eh_regions (saved_cfun, region, 0,
7648 					 new_label_mapper, new_label_map);
7649 	}
7650     }
7651 
7652   /* Initialize an empty loop tree.  */
7653   struct loops *loops = ggc_cleared_alloc<struct loops> ();
7654   init_loops_structure (dest_cfun, loops, 1);
7655   loops->state = LOOPS_MAY_HAVE_MULTIPLE_LATCHES;
7656   set_loops_for_fn (dest_cfun, loops);
7657 
7658   vec<loop_p, va_gc> *larray = get_loops (saved_cfun)->copy ();
7659 
7660   /* Move the outlined loop tree part.  */
7661   num_nodes = bbs.length ();
7662   FOR_EACH_VEC_ELT (bbs, i, bb)
7663     {
7664       if (bb->loop_father->header == bb)
7665 	{
7666 	  struct loop *this_loop = bb->loop_father;
7667 	  struct loop *outer = loop_outer (this_loop);
7668 	  if (outer == loop
7669 	      /* If the SESE region contains some bbs ending with
7670 		 a noreturn call, those are considered to belong
7671 		 to the outermost loop in saved_cfun, rather than
7672 		 the entry_bb's loop_father.  */
7673 	      || outer == loop0)
7674 	    {
7675 	      if (outer != loop)
7676 		num_nodes -= this_loop->num_nodes;
7677 	      flow_loop_tree_node_remove (bb->loop_father);
7678 	      flow_loop_tree_node_add (get_loop (dest_cfun, 0), this_loop);
7679 	      fixup_loop_arrays_after_move (saved_cfun, cfun, this_loop);
7680 	    }
7681 	}
7682       else if (bb->loop_father == loop0 && loop0 != loop)
7683 	num_nodes--;
7684 
7685       /* Remove loop exits from the outlined region.  */
7686       if (loops_for_fn (saved_cfun)->exits)
7687 	FOR_EACH_EDGE (e, ei, bb->succs)
7688 	  {
7689 	    struct loops *l = loops_for_fn (saved_cfun);
7690 	    loop_exit **slot
7691 	      = l->exits->find_slot_with_hash (e, htab_hash_pointer (e),
7692 					       NO_INSERT);
7693 	    if (slot)
7694 	      l->exits->clear_slot (slot);
7695 	  }
7696     }
7697 
7698   /* Adjust the number of blocks in the tree root of the outlined part.  */
7699   get_loop (dest_cfun, 0)->num_nodes = bbs.length () + 2;
7700 
7701   /* Setup a mapping to be used by move_block_to_fn.  */
7702   loop->aux = current_loops->tree_root;
7703   loop0->aux = current_loops->tree_root;
7704 
7705   /* Fix up orig_loop_num.  If the block referenced in it has been moved
7706      to dest_cfun, update orig_loop_num field, otherwise clear it.  */
7707   struct loop *dloop;
7708   signed char *moved_orig_loop_num = NULL;
7709   FOR_EACH_LOOP_FN (dest_cfun, dloop, 0)
7710     if (dloop->orig_loop_num)
7711       {
7712 	if (moved_orig_loop_num == NULL)
7713 	  moved_orig_loop_num
7714 	    = XCNEWVEC (signed char, vec_safe_length (larray));
7715 	if ((*larray)[dloop->orig_loop_num] != NULL
7716 	    && get_loop (saved_cfun, dloop->orig_loop_num) == NULL)
7717 	  {
7718 	    if (moved_orig_loop_num[dloop->orig_loop_num] >= 0
7719 		&& moved_orig_loop_num[dloop->orig_loop_num] < 2)
7720 	      moved_orig_loop_num[dloop->orig_loop_num]++;
7721 	    dloop->orig_loop_num = (*larray)[dloop->orig_loop_num]->num;
7722 	  }
7723 	else
7724 	  {
7725 	    moved_orig_loop_num[dloop->orig_loop_num] = -1;
7726 	    dloop->orig_loop_num = 0;
7727 	  }
7728       }
7729   pop_cfun ();
7730 
7731   if (moved_orig_loop_num)
7732     {
7733       FOR_EACH_VEC_ELT (bbs, i, bb)
7734 	{
7735 	  gimple *g = find_loop_dist_alias (bb);
7736 	  if (g == NULL)
7737 	    continue;
7738 
7739 	  int orig_loop_num = tree_to_shwi (gimple_call_arg (g, 0));
7740 	  gcc_assert (orig_loop_num
7741 		      && (unsigned) orig_loop_num < vec_safe_length (larray));
7742 	  if (moved_orig_loop_num[orig_loop_num] == 2)
7743 	    {
7744 	      /* If we have moved both loops with this orig_loop_num into
7745 		 dest_cfun and the LOOP_DIST_ALIAS call is being moved there
7746 		 too, update the first argument.  */
7747 	      gcc_assert ((*larray)[dloop->orig_loop_num] != NULL
7748 			  && (get_loop (saved_cfun, dloop->orig_loop_num)
7749 			      == NULL));
7750 	      tree t = build_int_cst (integer_type_node,
7751 				      (*larray)[dloop->orig_loop_num]->num);
7752 	      gimple_call_set_arg (g, 0, t);
7753 	      update_stmt (g);
7754 	      /* Make sure the following loop will not update it.  */
7755 	      moved_orig_loop_num[orig_loop_num] = 0;
7756 	    }
7757 	  else
7758 	    /* Otherwise at least one of the loops stayed in saved_cfun.
7759 	       Remove the LOOP_DIST_ALIAS call.  */
7760 	    fold_loop_internal_call (g, gimple_call_arg (g, 1));
7761 	}
7762       FOR_EACH_BB_FN (bb, saved_cfun)
7763 	{
7764 	  gimple *g = find_loop_dist_alias (bb);
7765 	  if (g == NULL)
7766 	    continue;
7767 	  int orig_loop_num = tree_to_shwi (gimple_call_arg (g, 0));
7768 	  gcc_assert (orig_loop_num
7769 		      && (unsigned) orig_loop_num < vec_safe_length (larray));
7770 	  if (moved_orig_loop_num[orig_loop_num])
7771 	    /* LOOP_DIST_ALIAS call remained in saved_cfun, if at least one
7772 	       of the corresponding loops was moved, remove it.  */
7773 	    fold_loop_internal_call (g, gimple_call_arg (g, 1));
7774 	}
7775       XDELETEVEC (moved_orig_loop_num);
7776     }
7777   ggc_free (larray);
7778 
7779   /* Move blocks from BBS into DEST_CFUN.  */
7780   gcc_assert (bbs.length () >= 2);
7781   after = dest_cfun->cfg->x_entry_block_ptr;
7782   hash_map<tree, tree> vars_map;
7783 
7784   memset (&d, 0, sizeof (d));
7785   d.orig_block = orig_block;
7786   d.new_block = DECL_INITIAL (dest_cfun->decl);
7787   d.from_context = cfun->decl;
7788   d.to_context = dest_cfun->decl;
7789   d.vars_map = &vars_map;
7790   d.new_label_map = new_label_map;
7791   d.eh_map = eh_map;
7792   d.remap_decls_p = true;
7793 
7794   if (gimple_in_ssa_p (cfun))
7795     for (tree arg = DECL_ARGUMENTS (d.to_context); arg; arg = DECL_CHAIN (arg))
7796       {
7797 	tree narg = make_ssa_name_fn (dest_cfun, arg, gimple_build_nop ());
7798 	set_ssa_default_def (dest_cfun, arg, narg);
7799 	vars_map.put (arg, narg);
7800       }
7801 
7802   FOR_EACH_VEC_ELT (bbs, i, bb)
7803     {
7804       /* No need to update edge counts on the last block.  It has
7805 	 already been updated earlier when we detached the region from
7806 	 the original CFG.  */
7807       move_block_to_fn (dest_cfun, bb, after, bb != exit_bb, &d);
7808       after = bb;
7809     }
7810 
7811   loop->aux = NULL;
7812   loop0->aux = NULL;
7813   /* Loop sizes are no longer correct, fix them up.  */
7814   loop->num_nodes -= num_nodes;
7815   for (struct loop *outer = loop_outer (loop);
7816        outer; outer = loop_outer (outer))
7817     outer->num_nodes -= num_nodes;
7818   loop0->num_nodes -= bbs.length () - num_nodes;
7819 
7820   if (saved_cfun->has_simduid_loops || saved_cfun->has_force_vectorize_loops)
7821     {
7822       struct loop *aloop;
7823       for (i = 0; vec_safe_iterate (loops->larray, i, &aloop); i++)
7824 	if (aloop != NULL)
7825 	  {
7826 	    if (aloop->simduid)
7827 	      {
7828 		replace_by_duplicate_decl (&aloop->simduid, d.vars_map,
7829 					   d.to_context);
7830 		dest_cfun->has_simduid_loops = true;
7831 	      }
7832 	    if (aloop->force_vectorize)
7833 	      dest_cfun->has_force_vectorize_loops = true;
7834 	  }
7835     }
7836 
7837   /* Rewire BLOCK_SUBBLOCKS of orig_block.  */
7838   if (orig_block)
7839     {
7840       tree block;
7841       gcc_assert (BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
7842 		  == NULL_TREE);
7843       BLOCK_SUBBLOCKS (DECL_INITIAL (dest_cfun->decl))
7844 	= BLOCK_SUBBLOCKS (orig_block);
7845       for (block = BLOCK_SUBBLOCKS (orig_block);
7846 	   block; block = BLOCK_CHAIN (block))
7847 	BLOCK_SUPERCONTEXT (block) = DECL_INITIAL (dest_cfun->decl);
7848       BLOCK_SUBBLOCKS (orig_block) = NULL_TREE;
7849     }
7850 
7851   replace_block_vars_by_duplicates (DECL_INITIAL (dest_cfun->decl),
7852 				    &vars_map, dest_cfun->decl);
7853 
7854   if (new_label_map)
7855     htab_delete (new_label_map);
7856   if (eh_map)
7857     delete eh_map;
7858 
7859   if (gimple_in_ssa_p (cfun))
7860     {
7861       /* We need to release ssa-names in a defined order, so first find them,
7862 	 and then iterate in ascending version order.  */
7863       bitmap release_names = BITMAP_ALLOC (NULL);
7864       vars_map.traverse<void *, gather_ssa_name_hash_map_from> (release_names);
7865       bitmap_iterator bi;
7866       unsigned i;
7867       EXECUTE_IF_SET_IN_BITMAP (release_names, 0, i, bi)
7868 	release_ssa_name (ssa_name (i));
7869       BITMAP_FREE (release_names);
7870     }
7871 
7872   /* Rewire the entry and exit blocks.  The successor to the entry
7873      block turns into the successor of DEST_FN's ENTRY_BLOCK_PTR in
7874      the child function.  Similarly, the predecessor of DEST_FN's
7875      EXIT_BLOCK_PTR turns into the predecessor of EXIT_BLOCK_PTR.  We
7876      need to switch CFUN between DEST_CFUN and SAVED_CFUN so that the
7877      various CFG manipulation function get to the right CFG.
7878 
7879      FIXME, this is silly.  The CFG ought to become a parameter to
7880      these helpers.  */
7881   push_cfun (dest_cfun);
7882   ENTRY_BLOCK_PTR_FOR_FN (cfun)->count = entry_bb->count;
7883   make_single_succ_edge (ENTRY_BLOCK_PTR_FOR_FN (cfun), entry_bb, EDGE_FALLTHRU);
7884   if (exit_bb)
7885     {
7886       make_single_succ_edge (exit_bb,  EXIT_BLOCK_PTR_FOR_FN (cfun), 0);
7887       EXIT_BLOCK_PTR_FOR_FN (cfun)->count = exit_bb->count;
7888     }
7889   else
7890     EXIT_BLOCK_PTR_FOR_FN (cfun)->count = profile_count::zero ();
7891   pop_cfun ();
7892 
7893   /* Back in the original function, the SESE region has disappeared,
7894      create a new basic block in its place.  */
7895   bb = create_empty_bb (entry_pred[0]);
7896   if (current_loops)
7897     add_bb_to_loop (bb, loop);
7898   for (i = 0; i < num_entry_edges; i++)
7899     {
7900       e = make_edge (entry_pred[i], bb, entry_flag[i]);
7901       e->probability = entry_prob[i];
7902     }
7903 
7904   for (i = 0; i < num_exit_edges; i++)
7905     {
7906       e = make_edge (bb, exit_succ[i], exit_flag[i]);
7907       e->probability = exit_prob[i];
7908     }
7909 
7910   set_immediate_dominator (CDI_DOMINATORS, bb, dom_entry);
7911   FOR_EACH_VEC_ELT (dom_bbs, i, abb)
7912     set_immediate_dominator (CDI_DOMINATORS, abb, bb);
7913   dom_bbs.release ();
7914 
7915   if (exit_bb)
7916     {
7917       free (exit_prob);
7918       free (exit_flag);
7919       free (exit_succ);
7920     }
7921   free (entry_prob);
7922   free (entry_flag);
7923   free (entry_pred);
7924   bbs.release ();
7925 
7926   return bb;
7927 }
7928 
7929 /* Dump default def DEF to file FILE using FLAGS and indentation
7930    SPC.  */
7931 
7932 static void
7933 dump_default_def (FILE *file, tree def, int spc, dump_flags_t flags)
7934 {
7935   for (int i = 0; i < spc; ++i)
7936     fprintf (file, " ");
7937   dump_ssaname_info_to_file (file, def, spc);
7938 
7939   print_generic_expr (file, TREE_TYPE (def), flags);
7940   fprintf (file, " ");
7941   print_generic_expr (file, def, flags);
7942   fprintf (file, " = ");
7943   print_generic_expr (file, SSA_NAME_VAR (def), flags);
7944   fprintf (file, ";\n");
7945 }
7946 
7947 /* Print no_sanitize attribute to FILE for a given attribute VALUE.  */
7948 
7949 static void
7950 print_no_sanitize_attr_value (FILE *file, tree value)
7951 {
7952   unsigned int flags = tree_to_uhwi (value);
7953   bool first = true;
7954   for (int i = 0; sanitizer_opts[i].name != NULL; ++i)
7955     {
7956       if ((sanitizer_opts[i].flag & flags) == sanitizer_opts[i].flag)
7957 	{
7958 	  if (!first)
7959 	    fprintf (file, " | ");
7960 	  fprintf (file, "%s", sanitizer_opts[i].name);
7961 	  first = false;
7962 	}
7963     }
7964 }
7965 
7966 /* Dump FUNCTION_DECL FN to file FILE using FLAGS (see TDF_* in dumpfile.h)
7967    */
7968 
7969 void
7970 dump_function_to_file (tree fndecl, FILE *file, dump_flags_t flags)
7971 {
7972   tree arg, var, old_current_fndecl = current_function_decl;
7973   struct function *dsf;
7974   bool ignore_topmost_bind = false, any_var = false;
7975   basic_block bb;
7976   tree chain;
7977   bool tmclone = (TREE_CODE (fndecl) == FUNCTION_DECL
7978 		  && decl_is_tm_clone (fndecl));
7979   struct function *fun = DECL_STRUCT_FUNCTION (fndecl);
7980 
7981   if (DECL_ATTRIBUTES (fndecl) != NULL_TREE)
7982     {
7983       fprintf (file, "__attribute__((");
7984 
7985       bool first = true;
7986       tree chain;
7987       for (chain = DECL_ATTRIBUTES (fndecl); chain;
7988 	   first = false, chain = TREE_CHAIN (chain))
7989 	{
7990 	  if (!first)
7991 	    fprintf (file, ", ");
7992 
7993 	  tree name = get_attribute_name (chain);
7994 	  print_generic_expr (file, name, dump_flags);
7995 	  if (TREE_VALUE (chain) != NULL_TREE)
7996 	    {
7997 	      fprintf (file, " (");
7998 
7999 	      if (strstr (IDENTIFIER_POINTER (name), "no_sanitize"))
8000 		print_no_sanitize_attr_value (file, TREE_VALUE (chain));
8001 	      else
8002 		print_generic_expr (file, TREE_VALUE (chain), dump_flags);
8003 	      fprintf (file, ")");
8004 	    }
8005 	}
8006 
8007       fprintf (file, "))\n");
8008     }
8009 
8010   current_function_decl = fndecl;
8011   if (flags & TDF_GIMPLE)
8012     {
8013       print_generic_expr (file, TREE_TYPE (TREE_TYPE (fndecl)),
8014 			  dump_flags | TDF_SLIM);
8015       fprintf (file, " __GIMPLE ()\n%s (", function_name (fun));
8016     }
8017   else
8018     fprintf (file, "%s %s(", function_name (fun), tmclone ? "[tm-clone] " : "");
8019 
8020   arg = DECL_ARGUMENTS (fndecl);
8021   while (arg)
8022     {
8023       print_generic_expr (file, TREE_TYPE (arg), dump_flags);
8024       fprintf (file, " ");
8025       print_generic_expr (file, arg, dump_flags);
8026       if (DECL_CHAIN (arg))
8027 	fprintf (file, ", ");
8028       arg = DECL_CHAIN (arg);
8029     }
8030   fprintf (file, ")\n");
8031 
8032   dsf = DECL_STRUCT_FUNCTION (fndecl);
8033   if (dsf && (flags & TDF_EH))
8034     dump_eh_tree (file, dsf);
8035 
8036   if (flags & TDF_RAW && !gimple_has_body_p (fndecl))
8037     {
8038       dump_node (fndecl, TDF_SLIM | flags, file);
8039       current_function_decl = old_current_fndecl;
8040       return;
8041     }
8042 
8043   /* When GIMPLE is lowered, the variables are no longer available in
8044      BIND_EXPRs, so display them separately.  */
8045   if (fun && fun->decl == fndecl && (fun->curr_properties & PROP_gimple_lcf))
8046     {
8047       unsigned ix;
8048       ignore_topmost_bind = true;
8049 
8050       fprintf (file, "{\n");
8051       if (gimple_in_ssa_p (fun)
8052 	  && (flags & TDF_ALIAS))
8053 	{
8054 	  for (arg = DECL_ARGUMENTS (fndecl); arg != NULL;
8055 	       arg = DECL_CHAIN (arg))
8056 	    {
8057 	      tree def = ssa_default_def (fun, arg);
8058 	      if (def)
8059 		dump_default_def (file, def, 2, flags);
8060 	    }
8061 
8062 	  tree res = DECL_RESULT (fun->decl);
8063 	  if (res != NULL_TREE
8064 	      && DECL_BY_REFERENCE (res))
8065 	    {
8066 	      tree def = ssa_default_def (fun, res);
8067 	      if (def)
8068 		dump_default_def (file, def, 2, flags);
8069 	    }
8070 
8071 	  tree static_chain = fun->static_chain_decl;
8072 	  if (static_chain != NULL_TREE)
8073 	    {
8074 	      tree def = ssa_default_def (fun, static_chain);
8075 	      if (def)
8076 		dump_default_def (file, def, 2, flags);
8077 	    }
8078 	}
8079 
8080       if (!vec_safe_is_empty (fun->local_decls))
8081 	FOR_EACH_LOCAL_DECL (fun, ix, var)
8082 	  {
8083 	    print_generic_decl (file, var, flags);
8084 	    fprintf (file, "\n");
8085 
8086 	    any_var = true;
8087 	  }
8088 
8089       tree name;
8090 
8091       if (gimple_in_ssa_p (cfun))
8092 	FOR_EACH_SSA_NAME (ix, name, cfun)
8093 	  {
8094 	    if (!SSA_NAME_VAR (name))
8095 	      {
8096 		fprintf (file, "  ");
8097 		print_generic_expr (file, TREE_TYPE (name), flags);
8098 		fprintf (file, " ");
8099 		print_generic_expr (file, name, flags);
8100 		fprintf (file, ";\n");
8101 
8102 		any_var = true;
8103 	      }
8104 	  }
8105     }
8106 
8107   if (fun && fun->decl == fndecl
8108       && fun->cfg
8109       && basic_block_info_for_fn (fun))
8110     {
8111       /* If the CFG has been built, emit a CFG-based dump.  */
8112       if (!ignore_topmost_bind)
8113 	fprintf (file, "{\n");
8114 
8115       if (any_var && n_basic_blocks_for_fn (fun))
8116 	fprintf (file, "\n");
8117 
8118       FOR_EACH_BB_FN (bb, fun)
8119 	dump_bb (file, bb, 2, flags);
8120 
8121       fprintf (file, "}\n");
8122     }
8123   else if (fun->curr_properties & PROP_gimple_any)
8124     {
8125       /* The function is now in GIMPLE form but the CFG has not been
8126 	 built yet.  Emit the single sequence of GIMPLE statements
8127 	 that make up its body.  */
8128       gimple_seq body = gimple_body (fndecl);
8129 
8130       if (gimple_seq_first_stmt (body)
8131 	  && gimple_seq_first_stmt (body) == gimple_seq_last_stmt (body)
8132 	  && gimple_code (gimple_seq_first_stmt (body)) == GIMPLE_BIND)
8133 	print_gimple_seq (file, body, 0, flags);
8134       else
8135 	{
8136 	  if (!ignore_topmost_bind)
8137 	    fprintf (file, "{\n");
8138 
8139 	  if (any_var)
8140 	    fprintf (file, "\n");
8141 
8142 	  print_gimple_seq (file, body, 2, flags);
8143 	  fprintf (file, "}\n");
8144 	}
8145     }
8146   else
8147     {
8148       int indent;
8149 
8150       /* Make a tree based dump.  */
8151       chain = DECL_SAVED_TREE (fndecl);
8152       if (chain && TREE_CODE (chain) == BIND_EXPR)
8153 	{
8154 	  if (ignore_topmost_bind)
8155 	    {
8156 	      chain = BIND_EXPR_BODY (chain);
8157 	      indent = 2;
8158 	    }
8159 	  else
8160 	    indent = 0;
8161 	}
8162       else
8163 	{
8164 	  if (!ignore_topmost_bind)
8165 	    {
8166 	      fprintf (file, "{\n");
8167 	      /* No topmost bind, pretend it's ignored for later.  */
8168 	      ignore_topmost_bind = true;
8169 	    }
8170 	  indent = 2;
8171 	}
8172 
8173       if (any_var)
8174 	fprintf (file, "\n");
8175 
8176       print_generic_stmt_indented (file, chain, flags, indent);
8177       if (ignore_topmost_bind)
8178 	fprintf (file, "}\n");
8179     }
8180 
8181   if (flags & TDF_ENUMERATE_LOCALS)
8182     dump_enumerated_decls (file, flags);
8183   fprintf (file, "\n\n");
8184 
8185   current_function_decl = old_current_fndecl;
8186 }
8187 
8188 /* Dump FUNCTION_DECL FN to stderr using FLAGS (see TDF_* in tree.h)  */
8189 
8190 DEBUG_FUNCTION void
8191 debug_function (tree fn, dump_flags_t flags)
8192 {
8193   dump_function_to_file (fn, stderr, flags);
8194 }
8195 
8196 
8197 /* Print on FILE the indexes for the predecessors of basic_block BB.  */
8198 
8199 static void
8200 print_pred_bbs (FILE *file, basic_block bb)
8201 {
8202   edge e;
8203   edge_iterator ei;
8204 
8205   FOR_EACH_EDGE (e, ei, bb->preds)
8206     fprintf (file, "bb_%d ", e->src->index);
8207 }
8208 
8209 
8210 /* Print on FILE the indexes for the successors of basic_block BB.  */
8211 
8212 static void
8213 print_succ_bbs (FILE *file, basic_block bb)
8214 {
8215   edge e;
8216   edge_iterator ei;
8217 
8218   FOR_EACH_EDGE (e, ei, bb->succs)
8219     fprintf (file, "bb_%d ", e->dest->index);
8220 }
8221 
8222 /* Print to FILE the basic block BB following the VERBOSITY level.  */
8223 
8224 void
8225 print_loops_bb (FILE *file, basic_block bb, int indent, int verbosity)
8226 {
8227   char *s_indent = (char *) alloca ((size_t) indent + 1);
8228   memset ((void *) s_indent, ' ', (size_t) indent);
8229   s_indent[indent] = '\0';
8230 
8231   /* Print basic_block's header.  */
8232   if (verbosity >= 2)
8233     {
8234       fprintf (file, "%s  bb_%d (preds = {", s_indent, bb->index);
8235       print_pred_bbs (file, bb);
8236       fprintf (file, "}, succs = {");
8237       print_succ_bbs (file, bb);
8238       fprintf (file, "})\n");
8239     }
8240 
8241   /* Print basic_block's body.  */
8242   if (verbosity >= 3)
8243     {
8244       fprintf (file, "%s  {\n", s_indent);
8245       dump_bb (file, bb, indent + 4, TDF_VOPS|TDF_MEMSYMS);
8246       fprintf (file, "%s  }\n", s_indent);
8247     }
8248 }
8249 
8250 static void print_loop_and_siblings (FILE *, struct loop *, int, int);
8251 
8252 /* Pretty print LOOP on FILE, indented INDENT spaces.  Following
8253    VERBOSITY level this outputs the contents of the loop, or just its
8254    structure.  */
8255 
8256 static void
8257 print_loop (FILE *file, struct loop *loop, int indent, int verbosity)
8258 {
8259   char *s_indent;
8260   basic_block bb;
8261 
8262   if (loop == NULL)
8263     return;
8264 
8265   s_indent = (char *) alloca ((size_t) indent + 1);
8266   memset ((void *) s_indent, ' ', (size_t) indent);
8267   s_indent[indent] = '\0';
8268 
8269   /* Print loop's header.  */
8270   fprintf (file, "%sloop_%d (", s_indent, loop->num);
8271   if (loop->header)
8272     fprintf (file, "header = %d", loop->header->index);
8273   else
8274     {
8275       fprintf (file, "deleted)\n");
8276       return;
8277     }
8278   if (loop->latch)
8279     fprintf (file, ", latch = %d", loop->latch->index);
8280   else
8281     fprintf (file, ", multiple latches");
8282   fprintf (file, ", niter = ");
8283   print_generic_expr (file, loop->nb_iterations);
8284 
8285   if (loop->any_upper_bound)
8286     {
8287       fprintf (file, ", upper_bound = ");
8288       print_decu (loop->nb_iterations_upper_bound, file);
8289     }
8290   if (loop->any_likely_upper_bound)
8291     {
8292       fprintf (file, ", likely_upper_bound = ");
8293       print_decu (loop->nb_iterations_likely_upper_bound, file);
8294     }
8295 
8296   if (loop->any_estimate)
8297     {
8298       fprintf (file, ", estimate = ");
8299       print_decu (loop->nb_iterations_estimate, file);
8300     }
8301   if (loop->unroll)
8302     fprintf (file, ", unroll = %d", loop->unroll);
8303   fprintf (file, ")\n");
8304 
8305   /* Print loop's body.  */
8306   if (verbosity >= 1)
8307     {
8308       fprintf (file, "%s{\n", s_indent);
8309       FOR_EACH_BB_FN (bb, cfun)
8310 	if (bb->loop_father == loop)
8311 	  print_loops_bb (file, bb, indent, verbosity);
8312 
8313       print_loop_and_siblings (file, loop->inner, indent + 2, verbosity);
8314       fprintf (file, "%s}\n", s_indent);
8315     }
8316 }
8317 
8318 /* Print the LOOP and its sibling loops on FILE, indented INDENT
8319    spaces.  Following VERBOSITY level this outputs the contents of the
8320    loop, or just its structure.  */
8321 
8322 static void
8323 print_loop_and_siblings (FILE *file, struct loop *loop, int indent,
8324 			 int verbosity)
8325 {
8326   if (loop == NULL)
8327     return;
8328 
8329   print_loop (file, loop, indent, verbosity);
8330   print_loop_and_siblings (file, loop->next, indent, verbosity);
8331 }
8332 
8333 /* Follow a CFG edge from the entry point of the program, and on entry
8334    of a loop, pretty print the loop structure on FILE.  */
8335 
8336 void
8337 print_loops (FILE *file, int verbosity)
8338 {
8339   basic_block bb;
8340 
8341   bb = ENTRY_BLOCK_PTR_FOR_FN (cfun);
8342   fprintf (file, "\nLoops in function: %s\n", current_function_name ());
8343   if (bb && bb->loop_father)
8344     print_loop_and_siblings (file, bb->loop_father, 0, verbosity);
8345 }
8346 
8347 /* Dump a loop.  */
8348 
8349 DEBUG_FUNCTION void
8350 debug (struct loop &ref)
8351 {
8352   print_loop (stderr, &ref, 0, /*verbosity*/0);
8353 }
8354 
8355 DEBUG_FUNCTION void
8356 debug (struct loop *ptr)
8357 {
8358   if (ptr)
8359     debug (*ptr);
8360   else
8361     fprintf (stderr, "<nil>\n");
8362 }
8363 
8364 /* Dump a loop verbosely.  */
8365 
8366 DEBUG_FUNCTION void
8367 debug_verbose (struct loop &ref)
8368 {
8369   print_loop (stderr, &ref, 0, /*verbosity*/3);
8370 }
8371 
8372 DEBUG_FUNCTION void
8373 debug_verbose (struct loop *ptr)
8374 {
8375   if (ptr)
8376     debug (*ptr);
8377   else
8378     fprintf (stderr, "<nil>\n");
8379 }
8380 
8381 
8382 /* Debugging loops structure at tree level, at some VERBOSITY level.  */
8383 
8384 DEBUG_FUNCTION void
8385 debug_loops (int verbosity)
8386 {
8387   print_loops (stderr, verbosity);
8388 }
8389 
8390 /* Print on stderr the code of LOOP, at some VERBOSITY level.  */
8391 
8392 DEBUG_FUNCTION void
8393 debug_loop (struct loop *loop, int verbosity)
8394 {
8395   print_loop (stderr, loop, 0, verbosity);
8396 }
8397 
8398 /* Print on stderr the code of loop number NUM, at some VERBOSITY
8399    level.  */
8400 
8401 DEBUG_FUNCTION void
8402 debug_loop_num (unsigned num, int verbosity)
8403 {
8404   debug_loop (get_loop (cfun, num), verbosity);
8405 }
8406 
8407 /* Return true if BB ends with a call, possibly followed by some
8408    instructions that must stay with the call.  Return false,
8409    otherwise.  */
8410 
8411 static bool
8412 gimple_block_ends_with_call_p (basic_block bb)
8413 {
8414   gimple_stmt_iterator gsi = gsi_last_nondebug_bb (bb);
8415   return !gsi_end_p (gsi) && is_gimple_call (gsi_stmt (gsi));
8416 }
8417 
8418 
8419 /* Return true if BB ends with a conditional branch.  Return false,
8420    otherwise.  */
8421 
8422 static bool
8423 gimple_block_ends_with_condjump_p (const_basic_block bb)
8424 {
8425   gimple *stmt = last_stmt (CONST_CAST_BB (bb));
8426   return (stmt && gimple_code (stmt) == GIMPLE_COND);
8427 }
8428 
8429 
8430 /* Return true if statement T may terminate execution of BB in ways not
8431    explicitly represtented in the CFG.  */
8432 
8433 bool
8434 stmt_can_terminate_bb_p (gimple *t)
8435 {
8436   tree fndecl = NULL_TREE;
8437   int call_flags = 0;
8438 
8439   /* Eh exception not handled internally terminates execution of the whole
8440      function.  */
8441   if (stmt_can_throw_external (t))
8442     return true;
8443 
8444   /* NORETURN and LONGJMP calls already have an edge to exit.
8445      CONST and PURE calls do not need one.
8446      We don't currently check for CONST and PURE here, although
8447      it would be a good idea, because those attributes are
8448      figured out from the RTL in mark_constant_function, and
8449      the counter incrementation code from -fprofile-arcs
8450      leads to different results from -fbranch-probabilities.  */
8451   if (is_gimple_call (t))
8452     {
8453       fndecl = gimple_call_fndecl (t);
8454       call_flags = gimple_call_flags (t);
8455     }
8456 
8457   if (is_gimple_call (t)
8458       && fndecl
8459       && DECL_BUILT_IN (fndecl)
8460       && (call_flags & ECF_NOTHROW)
8461       && !(call_flags & ECF_RETURNS_TWICE)
8462       /* fork() doesn't really return twice, but the effect of
8463          wrapping it in __gcov_fork() which calls __gcov_flush()
8464 	 and clears the counters before forking has the same
8465 	 effect as returning twice.  Force a fake edge.  */
8466       && !(DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
8467 	   && DECL_FUNCTION_CODE (fndecl) == BUILT_IN_FORK))
8468     return false;
8469 
8470   if (is_gimple_call (t))
8471     {
8472       edge_iterator ei;
8473       edge e;
8474       basic_block bb;
8475 
8476       if (call_flags & (ECF_PURE | ECF_CONST)
8477 	  && !(call_flags & ECF_LOOPING_CONST_OR_PURE))
8478 	return false;
8479 
8480       /* Function call may do longjmp, terminate program or do other things.
8481 	 Special case noreturn that have non-abnormal edges out as in this case
8482 	 the fact is sufficiently represented by lack of edges out of T.  */
8483       if (!(call_flags & ECF_NORETURN))
8484 	return true;
8485 
8486       bb = gimple_bb (t);
8487       FOR_EACH_EDGE (e, ei, bb->succs)
8488 	if ((e->flags & EDGE_FAKE) == 0)
8489 	  return true;
8490     }
8491 
8492   if (gasm *asm_stmt = dyn_cast <gasm *> (t))
8493     if (gimple_asm_volatile_p (asm_stmt) || gimple_asm_input_p (asm_stmt))
8494       return true;
8495 
8496   return false;
8497 }
8498 
8499 
8500 /* Add fake edges to the function exit for any non constant and non
8501    noreturn calls (or noreturn calls with EH/abnormal edges),
8502    volatile inline assembly in the bitmap of blocks specified by BLOCKS
8503    or to the whole CFG if BLOCKS is zero.  Return the number of blocks
8504    that were split.
8505 
8506    The goal is to expose cases in which entering a basic block does
8507    not imply that all subsequent instructions must be executed.  */
8508 
8509 static int
8510 gimple_flow_call_edges_add (sbitmap blocks)
8511 {
8512   int i;
8513   int blocks_split = 0;
8514   int last_bb = last_basic_block_for_fn (cfun);
8515   bool check_last_block = false;
8516 
8517   if (n_basic_blocks_for_fn (cfun) == NUM_FIXED_BLOCKS)
8518     return 0;
8519 
8520   if (! blocks)
8521     check_last_block = true;
8522   else
8523     check_last_block = bitmap_bit_p (blocks,
8524 				     EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb->index);
8525 
8526   /* In the last basic block, before epilogue generation, there will be
8527      a fallthru edge to EXIT.  Special care is required if the last insn
8528      of the last basic block is a call because make_edge folds duplicate
8529      edges, which would result in the fallthru edge also being marked
8530      fake, which would result in the fallthru edge being removed by
8531      remove_fake_edges, which would result in an invalid CFG.
8532 
8533      Moreover, we can't elide the outgoing fake edge, since the block
8534      profiler needs to take this into account in order to solve the minimal
8535      spanning tree in the case that the call doesn't return.
8536 
8537      Handle this by adding a dummy instruction in a new last basic block.  */
8538   if (check_last_block)
8539     {
8540       basic_block bb = EXIT_BLOCK_PTR_FOR_FN (cfun)->prev_bb;
8541       gimple_stmt_iterator gsi = gsi_last_nondebug_bb (bb);
8542       gimple *t = NULL;
8543 
8544       if (!gsi_end_p (gsi))
8545 	t = gsi_stmt (gsi);
8546 
8547       if (t && stmt_can_terminate_bb_p (t))
8548 	{
8549 	  edge e;
8550 
8551 	  e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun));
8552 	  if (e)
8553 	    {
8554 	      gsi_insert_on_edge (e, gimple_build_nop ());
8555 	      gsi_commit_edge_inserts ();
8556 	    }
8557 	}
8558     }
8559 
8560   /* Now add fake edges to the function exit for any non constant
8561      calls since there is no way that we can determine if they will
8562      return or not...  */
8563   for (i = 0; i < last_bb; i++)
8564     {
8565       basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i);
8566       gimple_stmt_iterator gsi;
8567       gimple *stmt, *last_stmt;
8568 
8569       if (!bb)
8570 	continue;
8571 
8572       if (blocks && !bitmap_bit_p (blocks, i))
8573 	continue;
8574 
8575       gsi = gsi_last_nondebug_bb (bb);
8576       if (!gsi_end_p (gsi))
8577 	{
8578 	  last_stmt = gsi_stmt (gsi);
8579 	  do
8580 	    {
8581 	      stmt = gsi_stmt (gsi);
8582 	      if (stmt_can_terminate_bb_p (stmt))
8583 		{
8584 		  edge e;
8585 
8586 		  /* The handling above of the final block before the
8587 		     epilogue should be enough to verify that there is
8588 		     no edge to the exit block in CFG already.
8589 		     Calling make_edge in such case would cause us to
8590 		     mark that edge as fake and remove it later.  */
8591 		  if (flag_checking && stmt == last_stmt)
8592 		    {
8593 		      e = find_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun));
8594 		      gcc_assert (e == NULL);
8595 		    }
8596 
8597 		  /* Note that the following may create a new basic block
8598 		     and renumber the existing basic blocks.  */
8599 		  if (stmt != last_stmt)
8600 		    {
8601 		      e = split_block (bb, stmt);
8602 		      if (e)
8603 			blocks_split++;
8604 		    }
8605 		  e = make_edge (bb, EXIT_BLOCK_PTR_FOR_FN (cfun), EDGE_FAKE);
8606 		  e->probability = profile_probability::guessed_never ();
8607 		}
8608 	      gsi_prev (&gsi);
8609 	    }
8610 	  while (!gsi_end_p (gsi));
8611 	}
8612     }
8613 
8614   if (blocks_split)
8615     checking_verify_flow_info ();
8616 
8617   return blocks_split;
8618 }
8619 
8620 /* Removes edge E and all the blocks dominated by it, and updates dominance
8621    information.  The IL in E->src needs to be updated separately.
8622    If dominance info is not available, only the edge E is removed.*/
8623 
8624 void
8625 remove_edge_and_dominated_blocks (edge e)
8626 {
8627   vec<basic_block> bbs_to_remove = vNULL;
8628   vec<basic_block> bbs_to_fix_dom = vNULL;
8629   edge f;
8630   edge_iterator ei;
8631   bool none_removed = false;
8632   unsigned i;
8633   basic_block bb, dbb;
8634   bitmap_iterator bi;
8635 
8636   /* If we are removing a path inside a non-root loop that may change
8637      loop ownership of blocks or remove loops.  Mark loops for fixup.  */
8638   if (current_loops
8639       && loop_outer (e->src->loop_father) != NULL
8640       && e->src->loop_father == e->dest->loop_father)
8641     loops_state_set (LOOPS_NEED_FIXUP);
8642 
8643   if (!dom_info_available_p (CDI_DOMINATORS))
8644     {
8645       remove_edge (e);
8646       return;
8647     }
8648 
8649   /* No updating is needed for edges to exit.  */
8650   if (e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
8651     {
8652       if (cfgcleanup_altered_bbs)
8653 	bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
8654       remove_edge (e);
8655       return;
8656     }
8657 
8658   /* First, we find the basic blocks to remove.  If E->dest has a predecessor
8659      that is not dominated by E->dest, then this set is empty.  Otherwise,
8660      all the basic blocks dominated by E->dest are removed.
8661 
8662      Also, to DF_IDOM we store the immediate dominators of the blocks in
8663      the dominance frontier of E (i.e., of the successors of the
8664      removed blocks, if there are any, and of E->dest otherwise).  */
8665   FOR_EACH_EDGE (f, ei, e->dest->preds)
8666     {
8667       if (f == e)
8668 	continue;
8669 
8670       if (!dominated_by_p (CDI_DOMINATORS, f->src, e->dest))
8671 	{
8672 	  none_removed = true;
8673 	  break;
8674 	}
8675     }
8676 
8677   auto_bitmap df, df_idom;
8678   if (none_removed)
8679     bitmap_set_bit (df_idom,
8680 		    get_immediate_dominator (CDI_DOMINATORS, e->dest)->index);
8681   else
8682     {
8683       bbs_to_remove = get_all_dominated_blocks (CDI_DOMINATORS, e->dest);
8684       FOR_EACH_VEC_ELT (bbs_to_remove, i, bb)
8685 	{
8686 	  FOR_EACH_EDGE (f, ei, bb->succs)
8687 	    {
8688 	      if (f->dest != EXIT_BLOCK_PTR_FOR_FN (cfun))
8689 		bitmap_set_bit (df, f->dest->index);
8690 	    }
8691 	}
8692       FOR_EACH_VEC_ELT (bbs_to_remove, i, bb)
8693 	bitmap_clear_bit (df, bb->index);
8694 
8695       EXECUTE_IF_SET_IN_BITMAP (df, 0, i, bi)
8696 	{
8697 	  bb = BASIC_BLOCK_FOR_FN (cfun, i);
8698 	  bitmap_set_bit (df_idom,
8699 			  get_immediate_dominator (CDI_DOMINATORS, bb)->index);
8700 	}
8701     }
8702 
8703   if (cfgcleanup_altered_bbs)
8704     {
8705       /* Record the set of the altered basic blocks.  */
8706       bitmap_set_bit (cfgcleanup_altered_bbs, e->src->index);
8707       bitmap_ior_into (cfgcleanup_altered_bbs, df);
8708     }
8709 
8710   /* Remove E and the cancelled blocks.  */
8711   if (none_removed)
8712     remove_edge (e);
8713   else
8714     {
8715       /* Walk backwards so as to get a chance to substitute all
8716 	 released DEFs into debug stmts.  See
8717 	 eliminate_unnecessary_stmts() in tree-ssa-dce.c for more
8718 	 details.  */
8719       for (i = bbs_to_remove.length (); i-- > 0; )
8720 	delete_basic_block (bbs_to_remove[i]);
8721     }
8722 
8723   /* Update the dominance information.  The immediate dominator may change only
8724      for blocks whose immediate dominator belongs to DF_IDOM:
8725 
8726      Suppose that idom(X) = Y before removal of E and idom(X) != Y after the
8727      removal.  Let Z the arbitrary block such that idom(Z) = Y and
8728      Z dominates X after the removal.  Before removal, there exists a path P
8729      from Y to X that avoids Z.  Let F be the last edge on P that is
8730      removed, and let W = F->dest.  Before removal, idom(W) = Y (since Y
8731      dominates W, and because of P, Z does not dominate W), and W belongs to
8732      the dominance frontier of E.  Therefore, Y belongs to DF_IDOM.  */
8733   EXECUTE_IF_SET_IN_BITMAP (df_idom, 0, i, bi)
8734     {
8735       bb = BASIC_BLOCK_FOR_FN (cfun, i);
8736       for (dbb = first_dom_son (CDI_DOMINATORS, bb);
8737 	   dbb;
8738 	   dbb = next_dom_son (CDI_DOMINATORS, dbb))
8739 	bbs_to_fix_dom.safe_push (dbb);
8740     }
8741 
8742   iterate_fix_dominators (CDI_DOMINATORS, bbs_to_fix_dom, true);
8743 
8744   bbs_to_remove.release ();
8745   bbs_to_fix_dom.release ();
8746 }
8747 
8748 /* Purge dead EH edges from basic block BB.  */
8749 
8750 bool
8751 gimple_purge_dead_eh_edges (basic_block bb)
8752 {
8753   bool changed = false;
8754   edge e;
8755   edge_iterator ei;
8756   gimple *stmt = last_stmt (bb);
8757 
8758   if (stmt && stmt_can_throw_internal (stmt))
8759     return false;
8760 
8761   for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
8762     {
8763       if (e->flags & EDGE_EH)
8764 	{
8765 	  remove_edge_and_dominated_blocks (e);
8766 	  changed = true;
8767 	}
8768       else
8769 	ei_next (&ei);
8770     }
8771 
8772   return changed;
8773 }
8774 
8775 /* Purge dead EH edges from basic block listed in BLOCKS.  */
8776 
8777 bool
8778 gimple_purge_all_dead_eh_edges (const_bitmap blocks)
8779 {
8780   bool changed = false;
8781   unsigned i;
8782   bitmap_iterator bi;
8783 
8784   EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
8785     {
8786       basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i);
8787 
8788       /* Earlier gimple_purge_dead_eh_edges could have removed
8789 	 this basic block already.  */
8790       gcc_assert (bb || changed);
8791       if (bb != NULL)
8792 	changed |= gimple_purge_dead_eh_edges (bb);
8793     }
8794 
8795   return changed;
8796 }
8797 
8798 /* Purge dead abnormal call edges from basic block BB.  */
8799 
8800 bool
8801 gimple_purge_dead_abnormal_call_edges (basic_block bb)
8802 {
8803   bool changed = false;
8804   edge e;
8805   edge_iterator ei;
8806   gimple *stmt = last_stmt (bb);
8807 
8808   if (!cfun->has_nonlocal_label
8809       && !cfun->calls_setjmp)
8810     return false;
8811 
8812   if (stmt && stmt_can_make_abnormal_goto (stmt))
8813     return false;
8814 
8815   for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); )
8816     {
8817       if (e->flags & EDGE_ABNORMAL)
8818 	{
8819 	  if (e->flags & EDGE_FALLTHRU)
8820 	    e->flags &= ~EDGE_ABNORMAL;
8821 	  else
8822 	    remove_edge_and_dominated_blocks (e);
8823 	  changed = true;
8824 	}
8825       else
8826 	ei_next (&ei);
8827     }
8828 
8829   return changed;
8830 }
8831 
8832 /* Purge dead abnormal call edges from basic block listed in BLOCKS.  */
8833 
8834 bool
8835 gimple_purge_all_dead_abnormal_call_edges (const_bitmap blocks)
8836 {
8837   bool changed = false;
8838   unsigned i;
8839   bitmap_iterator bi;
8840 
8841   EXECUTE_IF_SET_IN_BITMAP (blocks, 0, i, bi)
8842     {
8843       basic_block bb = BASIC_BLOCK_FOR_FN (cfun, i);
8844 
8845       /* Earlier gimple_purge_dead_abnormal_call_edges could have removed
8846 	 this basic block already.  */
8847       gcc_assert (bb || changed);
8848       if (bb != NULL)
8849 	changed |= gimple_purge_dead_abnormal_call_edges (bb);
8850     }
8851 
8852   return changed;
8853 }
8854 
8855 /* This function is called whenever a new edge is created or
8856    redirected.  */
8857 
8858 static void
8859 gimple_execute_on_growing_pred (edge e)
8860 {
8861   basic_block bb = e->dest;
8862 
8863   if (!gimple_seq_empty_p (phi_nodes (bb)))
8864     reserve_phi_args_for_new_edge (bb);
8865 }
8866 
8867 /* This function is called immediately before edge E is removed from
8868    the edge vector E->dest->preds.  */
8869 
8870 static void
8871 gimple_execute_on_shrinking_pred (edge e)
8872 {
8873   if (!gimple_seq_empty_p (phi_nodes (e->dest)))
8874     remove_phi_args (e);
8875 }
8876 
8877 /*---------------------------------------------------------------------------
8878   Helper functions for Loop versioning
8879   ---------------------------------------------------------------------------*/
8880 
8881 /* Adjust phi nodes for 'first' basic block.  'second' basic block is a copy
8882    of 'first'. Both of them are dominated by 'new_head' basic block. When
8883    'new_head' was created by 'second's incoming edge it received phi arguments
8884    on the edge by split_edge(). Later, additional edge 'e' was created to
8885    connect 'new_head' and 'first'. Now this routine adds phi args on this
8886    additional edge 'e' that new_head to second edge received as part of edge
8887    splitting.  */
8888 
8889 static void
8890 gimple_lv_adjust_loop_header_phi (basic_block first, basic_block second,
8891 				  basic_block new_head, edge e)
8892 {
8893   gphi *phi1, *phi2;
8894   gphi_iterator psi1, psi2;
8895   tree def;
8896   edge e2 = find_edge (new_head, second);
8897 
8898   /* Because NEW_HEAD has been created by splitting SECOND's incoming
8899      edge, we should always have an edge from NEW_HEAD to SECOND.  */
8900   gcc_assert (e2 != NULL);
8901 
8902   /* Browse all 'second' basic block phi nodes and add phi args to
8903      edge 'e' for 'first' head. PHI args are always in correct order.  */
8904 
8905   for (psi2 = gsi_start_phis (second),
8906        psi1 = gsi_start_phis (first);
8907        !gsi_end_p (psi2) && !gsi_end_p (psi1);
8908        gsi_next (&psi2),  gsi_next (&psi1))
8909     {
8910       phi1 = psi1.phi ();
8911       phi2 = psi2.phi ();
8912       def = PHI_ARG_DEF (phi2, e2->dest_idx);
8913       add_phi_arg (phi1, def, e, gimple_phi_arg_location_from_edge (phi2, e2));
8914     }
8915 }
8916 
8917 
8918 /* Adds a if else statement to COND_BB with condition COND_EXPR.
8919    SECOND_HEAD is the destination of the THEN and FIRST_HEAD is
8920    the destination of the ELSE part.  */
8921 
8922 static void
8923 gimple_lv_add_condition_to_bb (basic_block first_head ATTRIBUTE_UNUSED,
8924 			       basic_block second_head ATTRIBUTE_UNUSED,
8925 			       basic_block cond_bb, void *cond_e)
8926 {
8927   gimple_stmt_iterator gsi;
8928   gimple *new_cond_expr;
8929   tree cond_expr = (tree) cond_e;
8930   edge e0;
8931 
8932   /* Build new conditional expr */
8933   new_cond_expr = gimple_build_cond_from_tree (cond_expr,
8934 					       NULL_TREE, NULL_TREE);
8935 
8936   /* Add new cond in cond_bb.  */
8937   gsi = gsi_last_bb (cond_bb);
8938   gsi_insert_after (&gsi, new_cond_expr, GSI_NEW_STMT);
8939 
8940   /* Adjust edges appropriately to connect new head with first head
8941      as well as second head.  */
8942   e0 = single_succ_edge (cond_bb);
8943   e0->flags &= ~EDGE_FALLTHRU;
8944   e0->flags |= EDGE_FALSE_VALUE;
8945 }
8946 
8947 
8948 /* Do book-keeping of basic block BB for the profile consistency checker.
8949    If AFTER_PASS is 0, do pre-pass accounting, or if AFTER_PASS is 1
8950    then do post-pass accounting.  Store the counting in RECORD.  */
8951 static void
8952 gimple_account_profile_record (basic_block bb, int after_pass,
8953 			       struct profile_record *record)
8954 {
8955   gimple_stmt_iterator i;
8956   for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i))
8957     {
8958       record->size[after_pass]
8959 	+= estimate_num_insns (gsi_stmt (i), &eni_size_weights);
8960       if (bb->count.initialized_p ())
8961 	record->time[after_pass]
8962 	  += estimate_num_insns (gsi_stmt (i),
8963 				 &eni_time_weights) * bb->count.to_gcov_type ();
8964       else if (profile_status_for_fn (cfun) == PROFILE_GUESSED)
8965 	record->time[after_pass]
8966 	  += estimate_num_insns (gsi_stmt (i),
8967 				 &eni_time_weights) * bb->count.to_frequency (cfun);
8968     }
8969 }
8970 
8971 struct cfg_hooks gimple_cfg_hooks = {
8972   "gimple",
8973   gimple_verify_flow_info,
8974   gimple_dump_bb,		/* dump_bb  */
8975   gimple_dump_bb_for_graph,	/* dump_bb_for_graph  */
8976   create_bb,			/* create_basic_block  */
8977   gimple_redirect_edge_and_branch, /* redirect_edge_and_branch  */
8978   gimple_redirect_edge_and_branch_force, /* redirect_edge_and_branch_force  */
8979   gimple_can_remove_branch_p,	/* can_remove_branch_p  */
8980   remove_bb,			/* delete_basic_block  */
8981   gimple_split_block,		/* split_block  */
8982   gimple_move_block_after,	/* move_block_after  */
8983   gimple_can_merge_blocks_p,	/* can_merge_blocks_p  */
8984   gimple_merge_blocks,		/* merge_blocks  */
8985   gimple_predict_edge,		/* predict_edge  */
8986   gimple_predicted_by_p,	/* predicted_by_p  */
8987   gimple_can_duplicate_bb_p,	/* can_duplicate_block_p  */
8988   gimple_duplicate_bb,		/* duplicate_block  */
8989   gimple_split_edge,		/* split_edge  */
8990   gimple_make_forwarder_block,	/* make_forward_block  */
8991   NULL,				/* tidy_fallthru_edge  */
8992   NULL,				/* force_nonfallthru */
8993   gimple_block_ends_with_call_p,/* block_ends_with_call_p */
8994   gimple_block_ends_with_condjump_p, /* block_ends_with_condjump_p */
8995   gimple_flow_call_edges_add,   /* flow_call_edges_add */
8996   gimple_execute_on_growing_pred,	/* execute_on_growing_pred */
8997   gimple_execute_on_shrinking_pred, /* execute_on_shrinking_pred */
8998   gimple_duplicate_loop_to_header_edge, /* duplicate loop for trees */
8999   gimple_lv_add_condition_to_bb, /* lv_add_condition_to_bb */
9000   gimple_lv_adjust_loop_header_phi, /* lv_adjust_loop_header_phi*/
9001   extract_true_false_edges_from_block, /* extract_cond_bb_edges */
9002   flush_pending_stmts, 		/* flush_pending_stmts */
9003   gimple_empty_block_p,           /* block_empty_p */
9004   gimple_split_block_before_cond_jump, /* split_block_before_cond_jump */
9005   gimple_account_profile_record,
9006 };
9007 
9008 
9009 /* Split all critical edges.  */
9010 
9011 unsigned int
9012 split_critical_edges (void)
9013 {
9014   basic_block bb;
9015   edge e;
9016   edge_iterator ei;
9017 
9018   /* split_edge can redirect edges out of SWITCH_EXPRs, which can get
9019      expensive.  So we want to enable recording of edge to CASE_LABEL_EXPR
9020      mappings around the calls to split_edge.  */
9021   start_recording_case_labels ();
9022   FOR_ALL_BB_FN (bb, cfun)
9023     {
9024       FOR_EACH_EDGE (e, ei, bb->succs)
9025         {
9026 	  if (EDGE_CRITICAL_P (e) && !(e->flags & EDGE_ABNORMAL))
9027 	    split_edge (e);
9028 	  /* PRE inserts statements to edges and expects that
9029 	     since split_critical_edges was done beforehand, committing edge
9030 	     insertions will not split more edges.  In addition to critical
9031 	     edges we must split edges that have multiple successors and
9032 	     end by control flow statements, such as RESX.
9033 	     Go ahead and split them too.  This matches the logic in
9034 	     gimple_find_edge_insert_loc.  */
9035 	  else if ((!single_pred_p (e->dest)
9036 	            || !gimple_seq_empty_p (phi_nodes (e->dest))
9037 		    || e->dest == EXIT_BLOCK_PTR_FOR_FN (cfun))
9038 		   && e->src != ENTRY_BLOCK_PTR_FOR_FN (cfun)
9039 	           && !(e->flags & EDGE_ABNORMAL))
9040 	    {
9041 	      gimple_stmt_iterator gsi;
9042 
9043 	      gsi = gsi_last_bb (e->src);
9044 	      if (!gsi_end_p (gsi)
9045 		  && stmt_ends_bb_p (gsi_stmt (gsi))
9046 		  && (gimple_code (gsi_stmt (gsi)) != GIMPLE_RETURN
9047 		      && !gimple_call_builtin_p (gsi_stmt (gsi),
9048 						 BUILT_IN_RETURN)))
9049 		split_edge (e);
9050 	    }
9051 	}
9052     }
9053   end_recording_case_labels ();
9054   return 0;
9055 }
9056 
9057 namespace {
9058 
9059 const pass_data pass_data_split_crit_edges =
9060 {
9061   GIMPLE_PASS, /* type */
9062   "crited", /* name */
9063   OPTGROUP_NONE, /* optinfo_flags */
9064   TV_TREE_SPLIT_EDGES, /* tv_id */
9065   PROP_cfg, /* properties_required */
9066   PROP_no_crit_edges, /* properties_provided */
9067   0, /* properties_destroyed */
9068   0, /* todo_flags_start */
9069   0, /* todo_flags_finish */
9070 };
9071 
9072 class pass_split_crit_edges : public gimple_opt_pass
9073 {
9074 public:
9075   pass_split_crit_edges (gcc::context *ctxt)
9076     : gimple_opt_pass (pass_data_split_crit_edges, ctxt)
9077   {}
9078 
9079   /* opt_pass methods: */
9080   virtual unsigned int execute (function *) { return split_critical_edges (); }
9081 
9082   opt_pass * clone () { return new pass_split_crit_edges (m_ctxt); }
9083 }; // class pass_split_crit_edges
9084 
9085 } // anon namespace
9086 
9087 gimple_opt_pass *
9088 make_pass_split_crit_edges (gcc::context *ctxt)
9089 {
9090   return new pass_split_crit_edges (ctxt);
9091 }
9092 
9093 
9094 /* Insert COND expression which is GIMPLE_COND after STMT
9095    in basic block BB with appropriate basic block split
9096    and creation of a new conditionally executed basic block.
9097    Update profile so the new bb is visited with probability PROB.
9098    Return created basic block.  */
9099 basic_block
9100 insert_cond_bb (basic_block bb, gimple *stmt, gimple *cond,
9101 	        profile_probability prob)
9102 {
9103   edge fall = split_block (bb, stmt);
9104   gimple_stmt_iterator iter = gsi_last_bb (bb);
9105   basic_block new_bb;
9106 
9107   /* Insert cond statement.  */
9108   gcc_assert (gimple_code (cond) == GIMPLE_COND);
9109   if (gsi_end_p (iter))
9110     gsi_insert_before (&iter, cond, GSI_CONTINUE_LINKING);
9111   else
9112     gsi_insert_after (&iter, cond, GSI_CONTINUE_LINKING);
9113 
9114   /* Create conditionally executed block.  */
9115   new_bb = create_empty_bb (bb);
9116   edge e = make_edge (bb, new_bb, EDGE_TRUE_VALUE);
9117   e->probability = prob;
9118   new_bb->count = e->count ();
9119   make_single_succ_edge (new_bb, fall->dest, EDGE_FALLTHRU);
9120 
9121   /* Fix edge for split bb.  */
9122   fall->flags = EDGE_FALSE_VALUE;
9123   fall->probability -= e->probability;
9124 
9125   /* Update dominance info.  */
9126   if (dom_info_available_p (CDI_DOMINATORS))
9127     {
9128       set_immediate_dominator (CDI_DOMINATORS, new_bb, bb);
9129       set_immediate_dominator (CDI_DOMINATORS, fall->dest, bb);
9130     }
9131 
9132   /* Update loop info.  */
9133   if (current_loops)
9134     add_bb_to_loop (new_bb, bb->loop_father);
9135 
9136   return new_bb;
9137 }
9138 
9139 /* Build a ternary operation and gimplify it.  Emit code before GSI.
9140    Return the gimple_val holding the result.  */
9141 
9142 tree
9143 gimplify_build3 (gimple_stmt_iterator *gsi, enum tree_code code,
9144 		 tree type, tree a, tree b, tree c)
9145 {
9146   tree ret;
9147   location_t loc = gimple_location (gsi_stmt (*gsi));
9148 
9149   ret = fold_build3_loc (loc, code, type, a, b, c);
9150   STRIP_NOPS (ret);
9151 
9152   return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
9153                                    GSI_SAME_STMT);
9154 }
9155 
9156 /* Build a binary operation and gimplify it.  Emit code before GSI.
9157    Return the gimple_val holding the result.  */
9158 
9159 tree
9160 gimplify_build2 (gimple_stmt_iterator *gsi, enum tree_code code,
9161 		 tree type, tree a, tree b)
9162 {
9163   tree ret;
9164 
9165   ret = fold_build2_loc (gimple_location (gsi_stmt (*gsi)), code, type, a, b);
9166   STRIP_NOPS (ret);
9167 
9168   return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
9169                                    GSI_SAME_STMT);
9170 }
9171 
9172 /* Build a unary operation and gimplify it.  Emit code before GSI.
9173    Return the gimple_val holding the result.  */
9174 
9175 tree
9176 gimplify_build1 (gimple_stmt_iterator *gsi, enum tree_code code, tree type,
9177 		 tree a)
9178 {
9179   tree ret;
9180 
9181   ret = fold_build1_loc (gimple_location (gsi_stmt (*gsi)), code, type, a);
9182   STRIP_NOPS (ret);
9183 
9184   return force_gimple_operand_gsi (gsi, ret, true, NULL, true,
9185                                    GSI_SAME_STMT);
9186 }
9187 
9188 
9189 
9190 /* Given a basic block B which ends with a conditional and has
9191    precisely two successors, determine which of the edges is taken if
9192    the conditional is true and which is taken if the conditional is
9193    false.  Set TRUE_EDGE and FALSE_EDGE appropriately.  */
9194 
9195 void
9196 extract_true_false_edges_from_block (basic_block b,
9197 				     edge *true_edge,
9198 				     edge *false_edge)
9199 {
9200   edge e = EDGE_SUCC (b, 0);
9201 
9202   if (e->flags & EDGE_TRUE_VALUE)
9203     {
9204       *true_edge = e;
9205       *false_edge = EDGE_SUCC (b, 1);
9206     }
9207   else
9208     {
9209       *false_edge = e;
9210       *true_edge = EDGE_SUCC (b, 1);
9211     }
9212 }
9213 
9214 
9215 /* From a controlling predicate in the immediate dominator DOM of
9216    PHIBLOCK determine the edges into PHIBLOCK that are chosen if the
9217    predicate evaluates to true and false and store them to
9218    *TRUE_CONTROLLED_EDGE and *FALSE_CONTROLLED_EDGE if
9219    they are non-NULL.  Returns true if the edges can be determined,
9220    else return false.  */
9221 
9222 bool
9223 extract_true_false_controlled_edges (basic_block dom, basic_block phiblock,
9224 				     edge *true_controlled_edge,
9225 				     edge *false_controlled_edge)
9226 {
9227   basic_block bb = phiblock;
9228   edge true_edge, false_edge, tem;
9229   edge e0 = NULL, e1 = NULL;
9230 
9231   /* We have to verify that one edge into the PHI node is dominated
9232      by the true edge of the predicate block and the other edge
9233      dominated by the false edge.  This ensures that the PHI argument
9234      we are going to take is completely determined by the path we
9235      take from the predicate block.
9236      We can only use BB dominance checks below if the destination of
9237      the true/false edges are dominated by their edge, thus only
9238      have a single predecessor.  */
9239   extract_true_false_edges_from_block (dom, &true_edge, &false_edge);
9240   tem = EDGE_PRED (bb, 0);
9241   if (tem == true_edge
9242       || (single_pred_p (true_edge->dest)
9243 	  && (tem->src == true_edge->dest
9244 	      || dominated_by_p (CDI_DOMINATORS,
9245 				 tem->src, true_edge->dest))))
9246     e0 = tem;
9247   else if (tem == false_edge
9248 	   || (single_pred_p (false_edge->dest)
9249 	       && (tem->src == false_edge->dest
9250 		   || dominated_by_p (CDI_DOMINATORS,
9251 				      tem->src, false_edge->dest))))
9252     e1 = tem;
9253   else
9254     return false;
9255   tem = EDGE_PRED (bb, 1);
9256   if (tem == true_edge
9257       || (single_pred_p (true_edge->dest)
9258 	  && (tem->src == true_edge->dest
9259 	      || dominated_by_p (CDI_DOMINATORS,
9260 				 tem->src, true_edge->dest))))
9261     e0 = tem;
9262   else if (tem == false_edge
9263 	   || (single_pred_p (false_edge->dest)
9264 	       && (tem->src == false_edge->dest
9265 		   || dominated_by_p (CDI_DOMINATORS,
9266 				      tem->src, false_edge->dest))))
9267     e1 = tem;
9268   else
9269     return false;
9270   if (!e0 || !e1)
9271     return false;
9272 
9273   if (true_controlled_edge)
9274     *true_controlled_edge = e0;
9275   if (false_controlled_edge)
9276     *false_controlled_edge = e1;
9277 
9278   return true;
9279 }
9280 
9281 /* Generate a range test LHS CODE RHS that determines whether INDEX is in the
9282     range [low, high].  Place associated stmts before *GSI.  */
9283 
9284 void
9285 generate_range_test (basic_block bb, tree index, tree low, tree high,
9286 		     tree *lhs, tree *rhs)
9287 {
9288   tree type = TREE_TYPE (index);
9289   tree utype = unsigned_type_for (type);
9290 
9291   low = fold_convert (type, low);
9292   high = fold_convert (type, high);
9293 
9294   tree tmp = make_ssa_name (type);
9295   gassign *sub1
9296     = gimple_build_assign (tmp, MINUS_EXPR, index, low);
9297 
9298   *lhs = make_ssa_name (utype);
9299   gassign *a = gimple_build_assign (*lhs, NOP_EXPR, tmp);
9300 
9301   *rhs = fold_build2 (MINUS_EXPR, utype, high, low);
9302   gimple_stmt_iterator gsi = gsi_last_bb (bb);
9303   gsi_insert_before (&gsi, sub1, GSI_SAME_STMT);
9304   gsi_insert_before (&gsi, a, GSI_SAME_STMT);
9305 }
9306 
9307 /* Emit return warnings.  */
9308 
9309 namespace {
9310 
9311 const pass_data pass_data_warn_function_return =
9312 {
9313   GIMPLE_PASS, /* type */
9314   "*warn_function_return", /* name */
9315   OPTGROUP_NONE, /* optinfo_flags */
9316   TV_NONE, /* tv_id */
9317   PROP_cfg, /* properties_required */
9318   0, /* properties_provided */
9319   0, /* properties_destroyed */
9320   0, /* todo_flags_start */
9321   0, /* todo_flags_finish */
9322 };
9323 
9324 class pass_warn_function_return : public gimple_opt_pass
9325 {
9326 public:
9327   pass_warn_function_return (gcc::context *ctxt)
9328     : gimple_opt_pass (pass_data_warn_function_return, ctxt)
9329   {}
9330 
9331   /* opt_pass methods: */
9332   virtual unsigned int execute (function *);
9333 
9334 }; // class pass_warn_function_return
9335 
9336 unsigned int
9337 pass_warn_function_return::execute (function *fun)
9338 {
9339   source_location location;
9340   gimple *last;
9341   edge e;
9342   edge_iterator ei;
9343 
9344   if (!targetm.warn_func_return (fun->decl))
9345     return 0;
9346 
9347   /* If we have a path to EXIT, then we do return.  */
9348   if (TREE_THIS_VOLATILE (fun->decl)
9349       && EDGE_COUNT (EXIT_BLOCK_PTR_FOR_FN (fun)->preds) > 0)
9350     {
9351       location = UNKNOWN_LOCATION;
9352       for (ei = ei_start (EXIT_BLOCK_PTR_FOR_FN (fun)->preds);
9353 	   (e = ei_safe_edge (ei)); )
9354 	{
9355 	  last = last_stmt (e->src);
9356 	  if ((gimple_code (last) == GIMPLE_RETURN
9357 	       || gimple_call_builtin_p (last, BUILT_IN_RETURN))
9358 	      && location == UNKNOWN_LOCATION
9359 	      && ((location = LOCATION_LOCUS (gimple_location (last)))
9360 		  != UNKNOWN_LOCATION)
9361 	      && !optimize)
9362 	    break;
9363 	  /* When optimizing, replace return stmts in noreturn functions
9364 	     with __builtin_unreachable () call.  */
9365 	  if (optimize && gimple_code (last) == GIMPLE_RETURN)
9366 	    {
9367 	      tree fndecl = builtin_decl_implicit (BUILT_IN_UNREACHABLE);
9368 	      gimple *new_stmt = gimple_build_call (fndecl, 0);
9369 	      gimple_set_location (new_stmt, gimple_location (last));
9370 	      gimple_stmt_iterator gsi = gsi_for_stmt (last);
9371 	      gsi_replace (&gsi, new_stmt, true);
9372 	      remove_edge (e);
9373 	    }
9374 	  else
9375 	    ei_next (&ei);
9376 	}
9377       if (location == UNKNOWN_LOCATION)
9378 	location = cfun->function_end_locus;
9379       warning_at (location, 0, "%<noreturn%> function does return");
9380     }
9381 
9382   /* If we see "return;" in some basic block, then we do reach the end
9383      without returning a value.  */
9384   else if (warn_return_type > 0
9385 	   && !TREE_NO_WARNING (fun->decl)
9386 	   && !VOID_TYPE_P (TREE_TYPE (TREE_TYPE (fun->decl))))
9387     {
9388       FOR_EACH_EDGE (e, ei, EXIT_BLOCK_PTR_FOR_FN (fun)->preds)
9389 	{
9390 	  gimple *last = last_stmt (e->src);
9391 	  greturn *return_stmt = dyn_cast <greturn *> (last);
9392 	  if (return_stmt
9393 	      && gimple_return_retval (return_stmt) == NULL
9394 	      && !gimple_no_warning_p (last))
9395 	    {
9396 	      location = gimple_location (last);
9397 	      if (LOCATION_LOCUS (location) == UNKNOWN_LOCATION)
9398 		location = fun->function_end_locus;
9399 	      warning_at (location, OPT_Wreturn_type,
9400 			  "control reaches end of non-void function");
9401 	      TREE_NO_WARNING (fun->decl) = 1;
9402 	      break;
9403 	    }
9404 	}
9405       /* The C++ FE turns fallthrough from the end of non-void function
9406 	 into __builtin_unreachable () call with BUILTINS_LOCATION.
9407 	 Recognize those too.  */
9408       basic_block bb;
9409       if (!TREE_NO_WARNING (fun->decl))
9410 	FOR_EACH_BB_FN (bb, fun)
9411 	  if (EDGE_COUNT (bb->succs) == 0)
9412 	    {
9413 	      gimple *last = last_stmt (bb);
9414 	      const enum built_in_function ubsan_missing_ret
9415 		= BUILT_IN_UBSAN_HANDLE_MISSING_RETURN;
9416 	      if (last
9417 		  && ((LOCATION_LOCUS (gimple_location (last))
9418 		       == BUILTINS_LOCATION
9419 		       && gimple_call_builtin_p (last, BUILT_IN_UNREACHABLE))
9420 		      || gimple_call_builtin_p (last, ubsan_missing_ret)))
9421 		{
9422 		  gimple_stmt_iterator gsi = gsi_for_stmt (last);
9423 		  gsi_prev_nondebug (&gsi);
9424 		  gimple *prev = gsi_stmt (gsi);
9425 		  if (prev == NULL)
9426 		    location = UNKNOWN_LOCATION;
9427 		  else
9428 		    location = gimple_location (prev);
9429 		  if (LOCATION_LOCUS (location) == UNKNOWN_LOCATION)
9430 		    location = fun->function_end_locus;
9431 		  warning_at (location, OPT_Wreturn_type,
9432 			      "control reaches end of non-void function");
9433 		  TREE_NO_WARNING (fun->decl) = 1;
9434 		  break;
9435 		}
9436 	    }
9437     }
9438   return 0;
9439 }
9440 
9441 } // anon namespace
9442 
9443 gimple_opt_pass *
9444 make_pass_warn_function_return (gcc::context *ctxt)
9445 {
9446   return new pass_warn_function_return (ctxt);
9447 }
9448 
9449 /* Walk a gimplified function and warn for functions whose return value is
9450    ignored and attribute((warn_unused_result)) is set.  This is done before
9451    inlining, so we don't have to worry about that.  */
9452 
9453 static void
9454 do_warn_unused_result (gimple_seq seq)
9455 {
9456   tree fdecl, ftype;
9457   gimple_stmt_iterator i;
9458 
9459   for (i = gsi_start (seq); !gsi_end_p (i); gsi_next (&i))
9460     {
9461       gimple *g = gsi_stmt (i);
9462 
9463       switch (gimple_code (g))
9464 	{
9465 	case GIMPLE_BIND:
9466 	  do_warn_unused_result (gimple_bind_body (as_a <gbind *>(g)));
9467 	  break;
9468 	case GIMPLE_TRY:
9469 	  do_warn_unused_result (gimple_try_eval (g));
9470 	  do_warn_unused_result (gimple_try_cleanup (g));
9471 	  break;
9472 	case GIMPLE_CATCH:
9473 	  do_warn_unused_result (gimple_catch_handler (
9474 				   as_a <gcatch *> (g)));
9475 	  break;
9476 	case GIMPLE_EH_FILTER:
9477 	  do_warn_unused_result (gimple_eh_filter_failure (g));
9478 	  break;
9479 
9480 	case GIMPLE_CALL:
9481 	  if (gimple_call_lhs (g))
9482 	    break;
9483 	  if (gimple_call_internal_p (g))
9484 	    break;
9485 
9486 	  /* This is a naked call, as opposed to a GIMPLE_CALL with an
9487 	     LHS.  All calls whose value is ignored should be
9488 	     represented like this.  Look for the attribute.  */
9489 	  fdecl = gimple_call_fndecl (g);
9490 	  ftype = gimple_call_fntype (g);
9491 
9492 	  if (lookup_attribute ("warn_unused_result", TYPE_ATTRIBUTES (ftype)))
9493 	    {
9494 	      location_t loc = gimple_location (g);
9495 
9496 	      if (fdecl)
9497 		warning_at (loc, OPT_Wunused_result,
9498 			    "ignoring return value of %qD, "
9499 			    "declared with attribute warn_unused_result",
9500 			    fdecl);
9501 	      else
9502 		warning_at (loc, OPT_Wunused_result,
9503 			    "ignoring return value of function "
9504 			    "declared with attribute warn_unused_result");
9505 	    }
9506 	  break;
9507 
9508 	default:
9509 	  /* Not a container, not a call, or a call whose value is used.  */
9510 	  break;
9511 	}
9512     }
9513 }
9514 
9515 namespace {
9516 
9517 const pass_data pass_data_warn_unused_result =
9518 {
9519   GIMPLE_PASS, /* type */
9520   "*warn_unused_result", /* name */
9521   OPTGROUP_NONE, /* optinfo_flags */
9522   TV_NONE, /* tv_id */
9523   PROP_gimple_any, /* properties_required */
9524   0, /* properties_provided */
9525   0, /* properties_destroyed */
9526   0, /* todo_flags_start */
9527   0, /* todo_flags_finish */
9528 };
9529 
9530 class pass_warn_unused_result : public gimple_opt_pass
9531 {
9532 public:
9533   pass_warn_unused_result (gcc::context *ctxt)
9534     : gimple_opt_pass (pass_data_warn_unused_result, ctxt)
9535   {}
9536 
9537   /* opt_pass methods: */
9538   virtual bool gate (function *) { return flag_warn_unused_result; }
9539   virtual unsigned int execute (function *)
9540     {
9541       do_warn_unused_result (gimple_body (current_function_decl));
9542       return 0;
9543     }
9544 
9545 }; // class pass_warn_unused_result
9546 
9547 } // anon namespace
9548 
9549 gimple_opt_pass *
9550 make_pass_warn_unused_result (gcc::context *ctxt)
9551 {
9552   return new pass_warn_unused_result (ctxt);
9553 }
9554 
9555 /* IPA passes, compilation of earlier functions or inlining
9556    might have changed some properties, such as marked functions nothrow,
9557    pure, const or noreturn.
9558    Remove redundant edges and basic blocks, and create new ones if necessary.
9559 
9560    This pass can't be executed as stand alone pass from pass manager, because
9561    in between inlining and this fixup the verify_flow_info would fail.  */
9562 
9563 unsigned int
9564 execute_fixup_cfg (void)
9565 {
9566   basic_block bb;
9567   gimple_stmt_iterator gsi;
9568   int todo = 0;
9569   cgraph_node *node = cgraph_node::get (current_function_decl);
9570   profile_count num = node->count;
9571   profile_count den = ENTRY_BLOCK_PTR_FOR_FN (cfun)->count;
9572   bool scale = num.initialized_p () && !(num == den);
9573 
9574   if (scale)
9575     {
9576       profile_count::adjust_for_ipa_scaling (&num, &den);
9577       ENTRY_BLOCK_PTR_FOR_FN (cfun)->count = node->count;
9578       EXIT_BLOCK_PTR_FOR_FN (cfun)->count
9579         = EXIT_BLOCK_PTR_FOR_FN (cfun)->count.apply_scale (num, den);
9580     }
9581 
9582   FOR_EACH_BB_FN (bb, cfun)
9583     {
9584       if (scale)
9585         bb->count = bb->count.apply_scale (num, den);
9586       for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi);)
9587 	{
9588 	  gimple *stmt = gsi_stmt (gsi);
9589 	  tree decl = is_gimple_call (stmt)
9590 		      ? gimple_call_fndecl (stmt)
9591 		      : NULL;
9592 	  if (decl)
9593 	    {
9594 	      int flags = gimple_call_flags (stmt);
9595 	      if (flags & (ECF_CONST | ECF_PURE | ECF_LOOPING_CONST_OR_PURE))
9596 		{
9597 		  if (gimple_purge_dead_abnormal_call_edges (bb))
9598 		    todo |= TODO_cleanup_cfg;
9599 
9600 		  if (gimple_in_ssa_p (cfun))
9601 		    {
9602 		      todo |= TODO_update_ssa | TODO_cleanup_cfg;
9603 		      update_stmt (stmt);
9604 		    }
9605 		}
9606 
9607 	      if (flags & ECF_NORETURN
9608 		  && fixup_noreturn_call (stmt))
9609 		todo |= TODO_cleanup_cfg;
9610 	     }
9611 
9612 	  /* Remove stores to variables we marked write-only.
9613 	     Keep access when store has side effect, i.e. in case when source
9614 	     is volatile.  */
9615 	  if (gimple_store_p (stmt)
9616 	      && !gimple_has_side_effects (stmt))
9617 	    {
9618 	      tree lhs = get_base_address (gimple_get_lhs (stmt));
9619 
9620 	      if (VAR_P (lhs)
9621 		  && (TREE_STATIC (lhs) || DECL_EXTERNAL (lhs))
9622 		  && varpool_node::get (lhs)->writeonly)
9623 		{
9624 		  unlink_stmt_vdef (stmt);
9625 		  gsi_remove (&gsi, true);
9626 		  release_defs (stmt);
9627 	          todo |= TODO_update_ssa | TODO_cleanup_cfg;
9628 	          continue;
9629 		}
9630 	    }
9631 	  /* For calls we can simply remove LHS when it is known
9632 	     to be write-only.  */
9633 	  if (is_gimple_call (stmt)
9634 	      && gimple_get_lhs (stmt))
9635 	    {
9636 	      tree lhs = get_base_address (gimple_get_lhs (stmt));
9637 
9638 	      if (VAR_P (lhs)
9639 		  && (TREE_STATIC (lhs) || DECL_EXTERNAL (lhs))
9640 		  && varpool_node::get (lhs)->writeonly)
9641 		{
9642 		  gimple_call_set_lhs (stmt, NULL);
9643 		  update_stmt (stmt);
9644 	          todo |= TODO_update_ssa | TODO_cleanup_cfg;
9645 		}
9646 	    }
9647 
9648 	  if (maybe_clean_eh_stmt (stmt)
9649 	      && gimple_purge_dead_eh_edges (bb))
9650 	    todo |= TODO_cleanup_cfg;
9651 	  gsi_next (&gsi);
9652 	}
9653 
9654       /* If we have a basic block with no successors that does not
9655 	 end with a control statement or a noreturn call end it with
9656 	 a call to __builtin_unreachable.  This situation can occur
9657 	 when inlining a noreturn call that does in fact return.  */
9658       if (EDGE_COUNT (bb->succs) == 0)
9659 	{
9660 	  gimple *stmt = last_stmt (bb);
9661 	  if (!stmt
9662 	      || (!is_ctrl_stmt (stmt)
9663 		  && (!is_gimple_call (stmt)
9664 		      || !gimple_call_noreturn_p (stmt))))
9665 	    {
9666 	      if (stmt && is_gimple_call (stmt))
9667 		gimple_call_set_ctrl_altering (stmt, false);
9668 	      tree fndecl = builtin_decl_implicit (BUILT_IN_UNREACHABLE);
9669 	      stmt = gimple_build_call (fndecl, 0);
9670 	      gimple_stmt_iterator gsi = gsi_last_bb (bb);
9671 	      gsi_insert_after (&gsi, stmt, GSI_NEW_STMT);
9672 	      if (!cfun->after_inlining)
9673 		{
9674 		  gcall *call_stmt = dyn_cast <gcall *> (stmt);
9675 		  node->create_edge (cgraph_node::get_create (fndecl),
9676 				     call_stmt, bb->count);
9677 		}
9678 	    }
9679 	}
9680     }
9681   if (scale)
9682     compute_function_frequency ();
9683 
9684   if (current_loops
9685       && (todo & TODO_cleanup_cfg))
9686     loops_state_set (LOOPS_NEED_FIXUP);
9687 
9688   return todo;
9689 }
9690 
9691 namespace {
9692 
9693 const pass_data pass_data_fixup_cfg =
9694 {
9695   GIMPLE_PASS, /* type */
9696   "fixup_cfg", /* name */
9697   OPTGROUP_NONE, /* optinfo_flags */
9698   TV_NONE, /* tv_id */
9699   PROP_cfg, /* properties_required */
9700   0, /* properties_provided */
9701   0, /* properties_destroyed */
9702   0, /* todo_flags_start */
9703   0, /* todo_flags_finish */
9704 };
9705 
9706 class pass_fixup_cfg : public gimple_opt_pass
9707 {
9708 public:
9709   pass_fixup_cfg (gcc::context *ctxt)
9710     : gimple_opt_pass (pass_data_fixup_cfg, ctxt)
9711   {}
9712 
9713   /* opt_pass methods: */
9714   opt_pass * clone () { return new pass_fixup_cfg (m_ctxt); }
9715   virtual unsigned int execute (function *) { return execute_fixup_cfg (); }
9716 
9717 }; // class pass_fixup_cfg
9718 
9719 } // anon namespace
9720 
9721 gimple_opt_pass *
9722 make_pass_fixup_cfg (gcc::context *ctxt)
9723 {
9724   return new pass_fixup_cfg (ctxt);
9725 }
9726 
9727 /* Garbage collection support for edge_def.  */
9728 
9729 extern void gt_ggc_mx (tree&);
9730 extern void gt_ggc_mx (gimple *&);
9731 extern void gt_ggc_mx (rtx&);
9732 extern void gt_ggc_mx (basic_block&);
9733 
9734 static void
9735 gt_ggc_mx (rtx_insn *& x)
9736 {
9737   if (x)
9738     gt_ggc_mx_rtx_def ((void *) x);
9739 }
9740 
9741 void
9742 gt_ggc_mx (edge_def *e)
9743 {
9744   tree block = LOCATION_BLOCK (e->goto_locus);
9745   gt_ggc_mx (e->src);
9746   gt_ggc_mx (e->dest);
9747   if (current_ir_type () == IR_GIMPLE)
9748     gt_ggc_mx (e->insns.g);
9749   else
9750     gt_ggc_mx (e->insns.r);
9751   gt_ggc_mx (block);
9752 }
9753 
9754 /* PCH support for edge_def.  */
9755 
9756 extern void gt_pch_nx (tree&);
9757 extern void gt_pch_nx (gimple *&);
9758 extern void gt_pch_nx (rtx&);
9759 extern void gt_pch_nx (basic_block&);
9760 
9761 static void
9762 gt_pch_nx (rtx_insn *& x)
9763 {
9764   if (x)
9765     gt_pch_nx_rtx_def ((void *) x);
9766 }
9767 
9768 void
9769 gt_pch_nx (edge_def *e)
9770 {
9771   tree block = LOCATION_BLOCK (e->goto_locus);
9772   gt_pch_nx (e->src);
9773   gt_pch_nx (e->dest);
9774   if (current_ir_type () == IR_GIMPLE)
9775     gt_pch_nx (e->insns.g);
9776   else
9777     gt_pch_nx (e->insns.r);
9778   gt_pch_nx (block);
9779 }
9780 
9781 void
9782 gt_pch_nx (edge_def *e, gt_pointer_operator op, void *cookie)
9783 {
9784   tree block = LOCATION_BLOCK (e->goto_locus);
9785   op (&(e->src), cookie);
9786   op (&(e->dest), cookie);
9787   if (current_ir_type () == IR_GIMPLE)
9788     op (&(e->insns.g), cookie);
9789   else
9790     op (&(e->insns.r), cookie);
9791   op (&(block), cookie);
9792 }
9793 
9794 #if CHECKING_P
9795 
9796 namespace selftest {
9797 
9798 /* Helper function for CFG selftests: create a dummy function decl
9799    and push it as cfun.  */
9800 
9801 static tree
9802 push_fndecl (const char *name)
9803 {
9804   tree fn_type = build_function_type_array (integer_type_node, 0, NULL);
9805   /* FIXME: this uses input_location: */
9806   tree fndecl = build_fn_decl (name, fn_type);
9807   tree retval = build_decl (UNKNOWN_LOCATION, RESULT_DECL,
9808 			    NULL_TREE, integer_type_node);
9809   DECL_RESULT (fndecl) = retval;
9810   push_struct_function (fndecl);
9811   function *fun = DECL_STRUCT_FUNCTION (fndecl);
9812   ASSERT_TRUE (fun != NULL);
9813   init_empty_tree_cfg_for_function (fun);
9814   ASSERT_EQ (2, n_basic_blocks_for_fn (fun));
9815   ASSERT_EQ (0, n_edges_for_fn (fun));
9816   return fndecl;
9817 }
9818 
9819 /* These tests directly create CFGs.
9820    Compare with the static fns within tree-cfg.c:
9821      - build_gimple_cfg
9822      - make_blocks: calls create_basic_block (seq, bb);
9823      - make_edges.   */
9824 
9825 /* Verify a simple cfg of the form:
9826      ENTRY -> A -> B -> C -> EXIT.  */
9827 
9828 static void
9829 test_linear_chain ()
9830 {
9831   gimple_register_cfg_hooks ();
9832 
9833   tree fndecl = push_fndecl ("cfg_test_linear_chain");
9834   function *fun = DECL_STRUCT_FUNCTION (fndecl);
9835 
9836   /* Create some empty blocks.  */
9837   basic_block bb_a = create_empty_bb (ENTRY_BLOCK_PTR_FOR_FN (fun));
9838   basic_block bb_b = create_empty_bb (bb_a);
9839   basic_block bb_c = create_empty_bb (bb_b);
9840 
9841   ASSERT_EQ (5, n_basic_blocks_for_fn (fun));
9842   ASSERT_EQ (0, n_edges_for_fn (fun));
9843 
9844   /* Create some edges: a simple linear chain of BBs.  */
9845   make_edge (ENTRY_BLOCK_PTR_FOR_FN (fun), bb_a, EDGE_FALLTHRU);
9846   make_edge (bb_a, bb_b, 0);
9847   make_edge (bb_b, bb_c, 0);
9848   make_edge (bb_c, EXIT_BLOCK_PTR_FOR_FN (fun), 0);
9849 
9850   /* Verify the edges.  */
9851   ASSERT_EQ (4, n_edges_for_fn (fun));
9852   ASSERT_EQ (NULL, ENTRY_BLOCK_PTR_FOR_FN (fun)->preds);
9853   ASSERT_EQ (1, ENTRY_BLOCK_PTR_FOR_FN (fun)->succs->length ());
9854   ASSERT_EQ (1, bb_a->preds->length ());
9855   ASSERT_EQ (1, bb_a->succs->length ());
9856   ASSERT_EQ (1, bb_b->preds->length ());
9857   ASSERT_EQ (1, bb_b->succs->length ());
9858   ASSERT_EQ (1, bb_c->preds->length ());
9859   ASSERT_EQ (1, bb_c->succs->length ());
9860   ASSERT_EQ (1, EXIT_BLOCK_PTR_FOR_FN (fun)->preds->length ());
9861   ASSERT_EQ (NULL, EXIT_BLOCK_PTR_FOR_FN (fun)->succs);
9862 
9863   /* Verify the dominance information
9864      Each BB in our simple chain should be dominated by the one before
9865      it.  */
9866   calculate_dominance_info (CDI_DOMINATORS);
9867   ASSERT_EQ (bb_a, get_immediate_dominator (CDI_DOMINATORS, bb_b));
9868   ASSERT_EQ (bb_b, get_immediate_dominator (CDI_DOMINATORS, bb_c));
9869   vec<basic_block> dom_by_b = get_dominated_by (CDI_DOMINATORS, bb_b);
9870   ASSERT_EQ (1, dom_by_b.length ());
9871   ASSERT_EQ (bb_c, dom_by_b[0]);
9872   free_dominance_info (CDI_DOMINATORS);
9873   dom_by_b.release ();
9874 
9875   /* Similarly for post-dominance: each BB in our chain is post-dominated
9876      by the one after it.  */
9877   calculate_dominance_info (CDI_POST_DOMINATORS);
9878   ASSERT_EQ (bb_b, get_immediate_dominator (CDI_POST_DOMINATORS, bb_a));
9879   ASSERT_EQ (bb_c, get_immediate_dominator (CDI_POST_DOMINATORS, bb_b));
9880   vec<basic_block> postdom_by_b = get_dominated_by (CDI_POST_DOMINATORS, bb_b);
9881   ASSERT_EQ (1, postdom_by_b.length ());
9882   ASSERT_EQ (bb_a, postdom_by_b[0]);
9883   free_dominance_info (CDI_POST_DOMINATORS);
9884   postdom_by_b.release ();
9885 
9886   pop_cfun ();
9887 }
9888 
9889 /* Verify a simple CFG of the form:
9890      ENTRY
9891        |
9892        A
9893       / \
9894      /t  \f
9895     B     C
9896      \   /
9897       \ /
9898        D
9899        |
9900       EXIT.  */
9901 
9902 static void
9903 test_diamond ()
9904 {
9905   gimple_register_cfg_hooks ();
9906 
9907   tree fndecl = push_fndecl ("cfg_test_diamond");
9908   function *fun = DECL_STRUCT_FUNCTION (fndecl);
9909 
9910   /* Create some empty blocks.  */
9911   basic_block bb_a = create_empty_bb (ENTRY_BLOCK_PTR_FOR_FN (fun));
9912   basic_block bb_b = create_empty_bb (bb_a);
9913   basic_block bb_c = create_empty_bb (bb_a);
9914   basic_block bb_d = create_empty_bb (bb_b);
9915 
9916   ASSERT_EQ (6, n_basic_blocks_for_fn (fun));
9917   ASSERT_EQ (0, n_edges_for_fn (fun));
9918 
9919   /* Create the edges.  */
9920   make_edge (ENTRY_BLOCK_PTR_FOR_FN (fun), bb_a, EDGE_FALLTHRU);
9921   make_edge (bb_a, bb_b, EDGE_TRUE_VALUE);
9922   make_edge (bb_a, bb_c, EDGE_FALSE_VALUE);
9923   make_edge (bb_b, bb_d, 0);
9924   make_edge (bb_c, bb_d, 0);
9925   make_edge (bb_d, EXIT_BLOCK_PTR_FOR_FN (fun), 0);
9926 
9927   /* Verify the edges.  */
9928   ASSERT_EQ (6, n_edges_for_fn (fun));
9929   ASSERT_EQ (1, bb_a->preds->length ());
9930   ASSERT_EQ (2, bb_a->succs->length ());
9931   ASSERT_EQ (1, bb_b->preds->length ());
9932   ASSERT_EQ (1, bb_b->succs->length ());
9933   ASSERT_EQ (1, bb_c->preds->length ());
9934   ASSERT_EQ (1, bb_c->succs->length ());
9935   ASSERT_EQ (2, bb_d->preds->length ());
9936   ASSERT_EQ (1, bb_d->succs->length ());
9937 
9938   /* Verify the dominance information.  */
9939   calculate_dominance_info (CDI_DOMINATORS);
9940   ASSERT_EQ (bb_a, get_immediate_dominator (CDI_DOMINATORS, bb_b));
9941   ASSERT_EQ (bb_a, get_immediate_dominator (CDI_DOMINATORS, bb_c));
9942   ASSERT_EQ (bb_a, get_immediate_dominator (CDI_DOMINATORS, bb_d));
9943   vec<basic_block> dom_by_a = get_dominated_by (CDI_DOMINATORS, bb_a);
9944   ASSERT_EQ (3, dom_by_a.length ()); /* B, C, D, in some order.  */
9945   dom_by_a.release ();
9946   vec<basic_block> dom_by_b = get_dominated_by (CDI_DOMINATORS, bb_b);
9947   ASSERT_EQ (0, dom_by_b.length ());
9948   dom_by_b.release ();
9949   free_dominance_info (CDI_DOMINATORS);
9950 
9951   /* Similarly for post-dominance.  */
9952   calculate_dominance_info (CDI_POST_DOMINATORS);
9953   ASSERT_EQ (bb_d, get_immediate_dominator (CDI_POST_DOMINATORS, bb_a));
9954   ASSERT_EQ (bb_d, get_immediate_dominator (CDI_POST_DOMINATORS, bb_b));
9955   ASSERT_EQ (bb_d, get_immediate_dominator (CDI_POST_DOMINATORS, bb_c));
9956   vec<basic_block> postdom_by_d = get_dominated_by (CDI_POST_DOMINATORS, bb_d);
9957   ASSERT_EQ (3, postdom_by_d.length ()); /* A, B, C in some order.  */
9958   postdom_by_d.release ();
9959   vec<basic_block> postdom_by_b = get_dominated_by (CDI_POST_DOMINATORS, bb_b);
9960   ASSERT_EQ (0, postdom_by_b.length ());
9961   postdom_by_b.release ();
9962   free_dominance_info (CDI_POST_DOMINATORS);
9963 
9964   pop_cfun ();
9965 }
9966 
9967 /* Verify that we can handle a CFG containing a "complete" aka
9968    fully-connected subgraph (where A B C D below all have edges
9969    pointing to each other node, also to themselves).
9970    e.g.:
9971      ENTRY  EXIT
9972        |    ^
9973        |   /
9974        |  /
9975        | /
9976        V/
9977        A<--->B
9978        ^^   ^^
9979        | \ / |
9980        |  X  |
9981        | / \ |
9982        VV   VV
9983        C<--->D
9984 */
9985 
9986 static void
9987 test_fully_connected ()
9988 {
9989   gimple_register_cfg_hooks ();
9990 
9991   tree fndecl = push_fndecl ("cfg_fully_connected");
9992   function *fun = DECL_STRUCT_FUNCTION (fndecl);
9993 
9994   const int n = 4;
9995 
9996   /* Create some empty blocks.  */
9997   auto_vec <basic_block> subgraph_nodes;
9998   for (int i = 0; i < n; i++)
9999     subgraph_nodes.safe_push (create_empty_bb (ENTRY_BLOCK_PTR_FOR_FN (fun)));
10000 
10001   ASSERT_EQ (n + 2, n_basic_blocks_for_fn (fun));
10002   ASSERT_EQ (0, n_edges_for_fn (fun));
10003 
10004   /* Create the edges.  */
10005   make_edge (ENTRY_BLOCK_PTR_FOR_FN (fun), subgraph_nodes[0], EDGE_FALLTHRU);
10006   make_edge (subgraph_nodes[0], EXIT_BLOCK_PTR_FOR_FN (fun), 0);
10007   for (int i = 0; i < n; i++)
10008     for (int j = 0; j < n; j++)
10009       make_edge (subgraph_nodes[i], subgraph_nodes[j], 0);
10010 
10011   /* Verify the edges.  */
10012   ASSERT_EQ (2 + (n * n), n_edges_for_fn (fun));
10013   /* The first one is linked to ENTRY/EXIT as well as itself and
10014      everything else.  */
10015   ASSERT_EQ (n + 1, subgraph_nodes[0]->preds->length ());
10016   ASSERT_EQ (n + 1, subgraph_nodes[0]->succs->length ());
10017   /* The other ones in the subgraph are linked to everything in
10018      the subgraph (including themselves).  */
10019   for (int i = 1; i < n; i++)
10020     {
10021       ASSERT_EQ (n, subgraph_nodes[i]->preds->length ());
10022       ASSERT_EQ (n, subgraph_nodes[i]->succs->length ());
10023     }
10024 
10025   /* Verify the dominance information.  */
10026   calculate_dominance_info (CDI_DOMINATORS);
10027   /* The initial block in the subgraph should be dominated by ENTRY.  */
10028   ASSERT_EQ (ENTRY_BLOCK_PTR_FOR_FN (fun),
10029 	     get_immediate_dominator (CDI_DOMINATORS,
10030 				      subgraph_nodes[0]));
10031   /* Every other block in the subgraph should be dominated by the
10032      initial block.  */
10033   for (int i = 1; i < n; i++)
10034     ASSERT_EQ (subgraph_nodes[0],
10035 	       get_immediate_dominator (CDI_DOMINATORS,
10036 					subgraph_nodes[i]));
10037   free_dominance_info (CDI_DOMINATORS);
10038 
10039   /* Similarly for post-dominance.  */
10040   calculate_dominance_info (CDI_POST_DOMINATORS);
10041   /* The initial block in the subgraph should be postdominated by EXIT.  */
10042   ASSERT_EQ (EXIT_BLOCK_PTR_FOR_FN (fun),
10043 	     get_immediate_dominator (CDI_POST_DOMINATORS,
10044 				      subgraph_nodes[0]));
10045   /* Every other block in the subgraph should be postdominated by the
10046      initial block, since that leads to EXIT.  */
10047   for (int i = 1; i < n; i++)
10048     ASSERT_EQ (subgraph_nodes[0],
10049 	       get_immediate_dominator (CDI_POST_DOMINATORS,
10050 					subgraph_nodes[i]));
10051   free_dominance_info (CDI_POST_DOMINATORS);
10052 
10053   pop_cfun ();
10054 }
10055 
10056 /* Run all of the selftests within this file.  */
10057 
10058 void
10059 tree_cfg_c_tests ()
10060 {
10061   test_linear_chain ();
10062   test_diamond ();
10063   test_fully_connected ();
10064 }
10065 
10066 } // namespace selftest
10067 
10068 /* TODO: test the dominator/postdominator logic with various graphs/nodes:
10069    - loop
10070    - nested loops
10071    - switch statement (a block with many out-edges)
10072    - something that jumps to itself
10073    - etc  */
10074 
10075 #endif /* CHECKING_P */
10076