xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/final.c (revision b7b7574d3bf8eeb51a1fa3977b59142ec6434a55)
1 /* Convert RTL to assembler code and output it, for GNU compiler.
2    Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
3    1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010
4    Free Software Foundation, Inc.
5 
6 This file is part of GCC.
7 
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
11 version.
12 
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
16 for more details.
17 
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3.  If not see
20 <http://www.gnu.org/licenses/>.  */
21 
22 /* This is the final pass of the compiler.
23    It looks at the rtl code for a function and outputs assembler code.
24 
25    Call `final_start_function' to output the assembler code for function entry,
26    `final' to output assembler code for some RTL code,
27    `final_end_function' to output assembler code for function exit.
28    If a function is compiled in several pieces, each piece is
29    output separately with `final'.
30 
31    Some optimizations are also done at this level.
32    Move instructions that were made unnecessary by good register allocation
33    are detected and omitted from the output.  (Though most of these
34    are removed by the last jump pass.)
35 
36    Instructions to set the condition codes are omitted when it can be
37    seen that the condition codes already had the desired values.
38 
39    In some cases it is sufficient if the inherited condition codes
40    have related values, but this may require the following insn
41    (the one that tests the condition codes) to be modified.
42 
43    The code for the function prologue and epilogue are generated
44    directly in assembler by the target functions function_prologue and
45    function_epilogue.  Those instructions never exist as rtl.  */
46 
47 #include "config.h"
48 #include "system.h"
49 #include "coretypes.h"
50 #include "tm.h"
51 
52 #include "tree.h"
53 #include "rtl.h"
54 #include "tm_p.h"
55 #include "regs.h"
56 #include "insn-config.h"
57 #include "insn-attr.h"
58 #include "recog.h"
59 #include "conditions.h"
60 #include "flags.h"
61 #include "real.h"
62 #include "hard-reg-set.h"
63 #include "output.h"
64 #include "except.h"
65 #include "function.h"
66 #include "toplev.h"
67 #include "reload.h"
68 #include "intl.h"
69 #include "basic-block.h"
70 #include "target.h"
71 #include "debug.h"
72 #include "expr.h"
73 #include "cfglayout.h"
74 #include "tree-pass.h"
75 #include "tree-flow.h"
76 #include "timevar.h"
77 #include "cgraph.h"
78 #include "coverage.h"
79 #include "df.h"
80 #include "vecprim.h"
81 #include "ggc.h"
82 #include "cfgloop.h"
83 #include "params.h"
84 
85 #ifdef XCOFF_DEBUGGING_INFO
86 #include "xcoffout.h"		/* Needed for external data
87 				   declarations for e.g. AIX 4.x.  */
88 #endif
89 
90 #if defined (DWARF2_UNWIND_INFO) || defined (DWARF2_DEBUGGING_INFO)
91 #include "dwarf2out.h"
92 #endif
93 
94 #ifdef DBX_DEBUGGING_INFO
95 #include "dbxout.h"
96 #endif
97 
98 #ifdef SDB_DEBUGGING_INFO
99 #include "sdbout.h"
100 #endif
101 
102 /* If we aren't using cc0, CC_STATUS_INIT shouldn't exist.  So define a
103    null default for it to save conditionalization later.  */
104 #ifndef CC_STATUS_INIT
105 #define CC_STATUS_INIT
106 #endif
107 
108 /* How to start an assembler comment.  */
109 #ifndef ASM_COMMENT_START
110 #define ASM_COMMENT_START ";#"
111 #endif
112 
113 /* Is the given character a logical line separator for the assembler?  */
114 #ifndef IS_ASM_LOGICAL_LINE_SEPARATOR
115 #define IS_ASM_LOGICAL_LINE_SEPARATOR(C, STR) ((C) == ';')
116 #endif
117 
118 #ifndef JUMP_TABLES_IN_TEXT_SECTION
119 #define JUMP_TABLES_IN_TEXT_SECTION 0
120 #endif
121 
122 /* Bitflags used by final_scan_insn.  */
123 #define SEEN_BB		1
124 #define SEEN_NOTE	2
125 #define SEEN_EMITTED	4
126 
127 /* Last insn processed by final_scan_insn.  */
128 static rtx debug_insn;
129 rtx current_output_insn;
130 
131 /* Line number of last NOTE.  */
132 static int last_linenum;
133 
134 /* Last discriminator written to assembly.  */
135 static int last_discriminator;
136 
137 /* Discriminator of current block.  */
138 static int discriminator;
139 
140 /* Highest line number in current block.  */
141 static int high_block_linenum;
142 
143 /* Likewise for function.  */
144 static int high_function_linenum;
145 
146 /* Filename of last NOTE.  */
147 static const char *last_filename;
148 
149 /* Override filename and line number.  */
150 static const char *override_filename;
151 static int override_linenum;
152 
153 /* Whether to force emission of a line note before the next insn.  */
154 static bool force_source_line = false;
155 
156 extern const int length_unit_log; /* This is defined in insn-attrtab.c.  */
157 
158 /* Nonzero while outputting an `asm' with operands.
159    This means that inconsistencies are the user's fault, so don't die.
160    The precise value is the insn being output, to pass to error_for_asm.  */
161 rtx this_is_asm_operands;
162 
163 /* Number of operands of this insn, for an `asm' with operands.  */
164 static unsigned int insn_noperands;
165 
166 /* Compare optimization flag.  */
167 
168 static rtx last_ignored_compare = 0;
169 
170 /* Assign a unique number to each insn that is output.
171    This can be used to generate unique local labels.  */
172 
173 static int insn_counter = 0;
174 
175 #ifdef HAVE_cc0
176 /* This variable contains machine-dependent flags (defined in tm.h)
177    set and examined by output routines
178    that describe how to interpret the condition codes properly.  */
179 
180 CC_STATUS cc_status;
181 
182 /* During output of an insn, this contains a copy of cc_status
183    from before the insn.  */
184 
185 CC_STATUS cc_prev_status;
186 #endif
187 
188 /* Number of unmatched NOTE_INSN_BLOCK_BEG notes we have seen.  */
189 
190 static int block_depth;
191 
192 /* Nonzero if have enabled APP processing of our assembler output.  */
193 
194 static int app_on;
195 
196 /* If we are outputting an insn sequence, this contains the sequence rtx.
197    Zero otherwise.  */
198 
199 rtx final_sequence;
200 
201 #ifdef ASSEMBLER_DIALECT
202 
203 /* Number of the assembler dialect to use, starting at 0.  */
204 static int dialect_number;
205 #endif
206 
207 /* Nonnull if the insn currently being emitted was a COND_EXEC pattern.  */
208 rtx current_insn_predicate;
209 
210 /* True if printing into -fdump-final-insns= dump.  */
211 bool final_insns_dump_p;
212 
213 #ifdef HAVE_ATTR_length
214 static int asm_insn_count (rtx);
215 #endif
216 static void profile_function (FILE *);
217 static void profile_after_prologue (FILE *);
218 static bool notice_source_line (rtx, bool *);
219 static rtx walk_alter_subreg (rtx *, bool *);
220 static void output_asm_name (void);
221 static void output_alternate_entry_point (FILE *, rtx);
222 static tree get_mem_expr_from_op (rtx, int *);
223 static void output_asm_operand_names (rtx *, int *, int);
224 static void output_operand (rtx, int);
225 #ifdef LEAF_REGISTERS
226 static void leaf_renumber_regs (rtx);
227 #endif
228 #ifdef HAVE_cc0
229 static int alter_cond (rtx);
230 #endif
231 #ifndef ADDR_VEC_ALIGN
232 static int final_addr_vec_align (rtx);
233 #endif
234 #ifdef HAVE_ATTR_length
235 static int align_fuzz (rtx, rtx, int, unsigned);
236 #endif
237 
238 /* Initialize data in final at the beginning of a compilation.  */
239 
240 void
241 init_final (const char *filename ATTRIBUTE_UNUSED)
242 {
243   app_on = 0;
244   final_sequence = 0;
245 
246 #ifdef ASSEMBLER_DIALECT
247   dialect_number = ASSEMBLER_DIALECT;
248 #endif
249 }
250 
251 /* Default target function prologue and epilogue assembler output.
252 
253    If not overridden for epilogue code, then the function body itself
254    contains return instructions wherever needed.  */
255 void
256 default_function_pro_epilogue (FILE *file ATTRIBUTE_UNUSED,
257 			       HOST_WIDE_INT size ATTRIBUTE_UNUSED)
258 {
259 }
260 
261 /* Default target hook that outputs nothing to a stream.  */
262 void
263 no_asm_to_stream (FILE *file ATTRIBUTE_UNUSED)
264 {
265 }
266 
267 /* Enable APP processing of subsequent output.
268    Used before the output from an `asm' statement.  */
269 
270 void
271 app_enable (void)
272 {
273   if (! app_on)
274     {
275       fputs (ASM_APP_ON, asm_out_file);
276       app_on = 1;
277     }
278 }
279 
280 /* Disable APP processing of subsequent output.
281    Called from varasm.c before most kinds of output.  */
282 
283 void
284 app_disable (void)
285 {
286   if (app_on)
287     {
288       fputs (ASM_APP_OFF, asm_out_file);
289       app_on = 0;
290     }
291 }
292 
293 /* Return the number of slots filled in the current
294    delayed branch sequence (we don't count the insn needing the
295    delay slot).   Zero if not in a delayed branch sequence.  */
296 
297 #ifdef DELAY_SLOTS
298 int
299 dbr_sequence_length (void)
300 {
301   if (final_sequence != 0)
302     return XVECLEN (final_sequence, 0) - 1;
303   else
304     return 0;
305 }
306 #endif
307 
308 /* The next two pages contain routines used to compute the length of an insn
309    and to shorten branches.  */
310 
311 /* Arrays for insn lengths, and addresses.  The latter is referenced by
312    `insn_current_length'.  */
313 
314 static int *insn_lengths;
315 
316 VEC(int,heap) *insn_addresses_;
317 
318 /* Max uid for which the above arrays are valid.  */
319 static int insn_lengths_max_uid;
320 
321 /* Address of insn being processed.  Used by `insn_current_length'.  */
322 int insn_current_address;
323 
324 /* Address of insn being processed in previous iteration.  */
325 int insn_last_address;
326 
327 /* known invariant alignment of insn being processed.  */
328 int insn_current_align;
329 
330 /* After shorten_branches, for any insn, uid_align[INSN_UID (insn)]
331    gives the next following alignment insn that increases the known
332    alignment, or NULL_RTX if there is no such insn.
333    For any alignment obtained this way, we can again index uid_align with
334    its uid to obtain the next following align that in turn increases the
335    alignment, till we reach NULL_RTX; the sequence obtained this way
336    for each insn we'll call the alignment chain of this insn in the following
337    comments.  */
338 
339 struct label_alignment
340 {
341   short alignment;
342   short max_skip;
343 };
344 
345 static rtx *uid_align;
346 static int *uid_shuid;
347 static struct label_alignment *label_align;
348 
349 /* Indicate that branch shortening hasn't yet been done.  */
350 
351 void
352 init_insn_lengths (void)
353 {
354   if (uid_shuid)
355     {
356       free (uid_shuid);
357       uid_shuid = 0;
358     }
359   if (insn_lengths)
360     {
361       free (insn_lengths);
362       insn_lengths = 0;
363       insn_lengths_max_uid = 0;
364     }
365 #ifdef HAVE_ATTR_length
366   INSN_ADDRESSES_FREE ();
367 #endif
368   if (uid_align)
369     {
370       free (uid_align);
371       uid_align = 0;
372     }
373 }
374 
375 /* Obtain the current length of an insn.  If branch shortening has been done,
376    get its actual length.  Otherwise, use FALLBACK_FN to calculate the
377    length.  */
378 static inline int
379 get_attr_length_1 (rtx insn ATTRIBUTE_UNUSED,
380 		   int (*fallback_fn) (rtx) ATTRIBUTE_UNUSED)
381 {
382 #ifdef HAVE_ATTR_length
383   rtx body;
384   int i;
385   int length = 0;
386 
387   if (insn_lengths_max_uid > INSN_UID (insn))
388     return insn_lengths[INSN_UID (insn)];
389   else
390     switch (GET_CODE (insn))
391       {
392       case NOTE:
393       case BARRIER:
394       case CODE_LABEL:
395       case DEBUG_INSN:
396 	return 0;
397 
398       case CALL_INSN:
399 	length = fallback_fn (insn);
400 	break;
401 
402       case JUMP_INSN:
403 	body = PATTERN (insn);
404 	if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
405 	  {
406 	    /* Alignment is machine-dependent and should be handled by
407 	       ADDR_VEC_ALIGN.  */
408 	  }
409 	else
410 	  length = fallback_fn (insn);
411 	break;
412 
413       case INSN:
414 	body = PATTERN (insn);
415 	if (GET_CODE (body) == USE || GET_CODE (body) == CLOBBER)
416 	  return 0;
417 
418 	else if (GET_CODE (body) == ASM_INPUT || asm_noperands (body) >= 0)
419 	  length = asm_insn_count (body) * fallback_fn (insn);
420 	else if (GET_CODE (body) == SEQUENCE)
421 	  for (i = 0; i < XVECLEN (body, 0); i++)
422 	    length += get_attr_length_1 (XVECEXP (body, 0, i), fallback_fn);
423 	else
424 	  length = fallback_fn (insn);
425 	break;
426 
427       default:
428 	break;
429       }
430 
431 #ifdef ADJUST_INSN_LENGTH
432   ADJUST_INSN_LENGTH (insn, length);
433 #endif
434   return length;
435 #else /* not HAVE_ATTR_length */
436   return 0;
437 #define insn_default_length 0
438 #define insn_min_length 0
439 #endif /* not HAVE_ATTR_length */
440 }
441 
442 /* Obtain the current length of an insn.  If branch shortening has been done,
443    get its actual length.  Otherwise, get its maximum length.  */
444 int
445 get_attr_length (rtx insn)
446 {
447   return get_attr_length_1 (insn, insn_default_length);
448 }
449 
450 /* Obtain the current length of an insn.  If branch shortening has been done,
451    get its actual length.  Otherwise, get its minimum length.  */
452 int
453 get_attr_min_length (rtx insn)
454 {
455   return get_attr_length_1 (insn, insn_min_length);
456 }
457 
458 /* Code to handle alignment inside shorten_branches.  */
459 
460 /* Here is an explanation how the algorithm in align_fuzz can give
461    proper results:
462 
463    Call a sequence of instructions beginning with alignment point X
464    and continuing until the next alignment point `block X'.  When `X'
465    is used in an expression, it means the alignment value of the
466    alignment point.
467 
468    Call the distance between the start of the first insn of block X, and
469    the end of the last insn of block X `IX', for the `inner size of X'.
470    This is clearly the sum of the instruction lengths.
471 
472    Likewise with the next alignment-delimited block following X, which we
473    shall call block Y.
474 
475    Call the distance between the start of the first insn of block X, and
476    the start of the first insn of block Y `OX', for the `outer size of X'.
477 
478    The estimated padding is then OX - IX.
479 
480    OX can be safely estimated as
481 
482            if (X >= Y)
483                    OX = round_up(IX, Y)
484            else
485                    OX = round_up(IX, X) + Y - X
486 
487    Clearly est(IX) >= real(IX), because that only depends on the
488    instruction lengths, and those being overestimated is a given.
489 
490    Clearly round_up(foo, Z) >= round_up(bar, Z) if foo >= bar, so
491    we needn't worry about that when thinking about OX.
492 
493    When X >= Y, the alignment provided by Y adds no uncertainty factor
494    for branch ranges starting before X, so we can just round what we have.
495    But when X < Y, we don't know anything about the, so to speak,
496    `middle bits', so we have to assume the worst when aligning up from an
497    address mod X to one mod Y, which is Y - X.  */
498 
499 #ifndef LABEL_ALIGN
500 #define LABEL_ALIGN(LABEL) align_labels_log
501 #endif
502 
503 #ifndef LABEL_ALIGN_MAX_SKIP
504 #define LABEL_ALIGN_MAX_SKIP align_labels_max_skip
505 #endif
506 
507 #ifndef LOOP_ALIGN
508 #define LOOP_ALIGN(LABEL) align_loops_log
509 #endif
510 
511 #ifndef LOOP_ALIGN_MAX_SKIP
512 #define LOOP_ALIGN_MAX_SKIP align_loops_max_skip
513 #endif
514 
515 #ifndef LABEL_ALIGN_AFTER_BARRIER
516 #define LABEL_ALIGN_AFTER_BARRIER(LABEL) 0
517 #endif
518 
519 #ifndef LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP
520 #define LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP 0
521 #endif
522 
523 #ifndef JUMP_ALIGN
524 #define JUMP_ALIGN(LABEL) align_jumps_log
525 #endif
526 
527 #ifndef JUMP_ALIGN_MAX_SKIP
528 #define JUMP_ALIGN_MAX_SKIP align_jumps_max_skip
529 #endif
530 
531 #ifndef ADDR_VEC_ALIGN
532 static int
533 final_addr_vec_align (rtx addr_vec)
534 {
535   int align = GET_MODE_SIZE (GET_MODE (PATTERN (addr_vec)));
536 
537   if (align > BIGGEST_ALIGNMENT / BITS_PER_UNIT)
538     align = BIGGEST_ALIGNMENT / BITS_PER_UNIT;
539   return exact_log2 (align);
540 
541 }
542 
543 #define ADDR_VEC_ALIGN(ADDR_VEC) final_addr_vec_align (ADDR_VEC)
544 #endif
545 
546 #ifndef INSN_LENGTH_ALIGNMENT
547 #define INSN_LENGTH_ALIGNMENT(INSN) length_unit_log
548 #endif
549 
550 #define INSN_SHUID(INSN) (uid_shuid[INSN_UID (INSN)])
551 
552 static int min_labelno, max_labelno;
553 
554 #define LABEL_TO_ALIGNMENT(LABEL) \
555   (label_align[CODE_LABEL_NUMBER (LABEL) - min_labelno].alignment)
556 
557 #define LABEL_TO_MAX_SKIP(LABEL) \
558   (label_align[CODE_LABEL_NUMBER (LABEL) - min_labelno].max_skip)
559 
560 /* For the benefit of port specific code do this also as a function.  */
561 
562 int
563 label_to_alignment (rtx label)
564 {
565   if (CODE_LABEL_NUMBER (label) <= max_labelno)
566     return LABEL_TO_ALIGNMENT (label);
567   return 0;
568 }
569 
570 int
571 label_to_max_skip (rtx label)
572 {
573   if (CODE_LABEL_NUMBER (label) <= max_labelno)
574     return LABEL_TO_MAX_SKIP (label);
575   return 0;
576 }
577 
578 #ifdef HAVE_ATTR_length
579 /* The differences in addresses
580    between a branch and its target might grow or shrink depending on
581    the alignment the start insn of the range (the branch for a forward
582    branch or the label for a backward branch) starts out on; if these
583    differences are used naively, they can even oscillate infinitely.
584    We therefore want to compute a 'worst case' address difference that
585    is independent of the alignment the start insn of the range end
586    up on, and that is at least as large as the actual difference.
587    The function align_fuzz calculates the amount we have to add to the
588    naively computed difference, by traversing the part of the alignment
589    chain of the start insn of the range that is in front of the end insn
590    of the range, and considering for each alignment the maximum amount
591    that it might contribute to a size increase.
592 
593    For casesi tables, we also want to know worst case minimum amounts of
594    address difference, in case a machine description wants to introduce
595    some common offset that is added to all offsets in a table.
596    For this purpose, align_fuzz with a growth argument of 0 computes the
597    appropriate adjustment.  */
598 
599 /* Compute the maximum delta by which the difference of the addresses of
600    START and END might grow / shrink due to a different address for start
601    which changes the size of alignment insns between START and END.
602    KNOWN_ALIGN_LOG is the alignment known for START.
603    GROWTH should be ~0 if the objective is to compute potential code size
604    increase, and 0 if the objective is to compute potential shrink.
605    The return value is undefined for any other value of GROWTH.  */
606 
607 static int
608 align_fuzz (rtx start, rtx end, int known_align_log, unsigned int growth)
609 {
610   int uid = INSN_UID (start);
611   rtx align_label;
612   int known_align = 1 << known_align_log;
613   int end_shuid = INSN_SHUID (end);
614   int fuzz = 0;
615 
616   for (align_label = uid_align[uid]; align_label; align_label = uid_align[uid])
617     {
618       int align_addr, new_align;
619 
620       uid = INSN_UID (align_label);
621       align_addr = INSN_ADDRESSES (uid) - insn_lengths[uid];
622       if (uid_shuid[uid] > end_shuid)
623 	break;
624       known_align_log = LABEL_TO_ALIGNMENT (align_label);
625       new_align = 1 << known_align_log;
626       if (new_align < known_align)
627 	continue;
628       fuzz += (-align_addr ^ growth) & (new_align - known_align);
629       known_align = new_align;
630     }
631   return fuzz;
632 }
633 
634 /* Compute a worst-case reference address of a branch so that it
635    can be safely used in the presence of aligned labels.  Since the
636    size of the branch itself is unknown, the size of the branch is
637    not included in the range.  I.e. for a forward branch, the reference
638    address is the end address of the branch as known from the previous
639    branch shortening pass, minus a value to account for possible size
640    increase due to alignment.  For a backward branch, it is the start
641    address of the branch as known from the current pass, plus a value
642    to account for possible size increase due to alignment.
643    NB.: Therefore, the maximum offset allowed for backward branches needs
644    to exclude the branch size.  */
645 
646 int
647 insn_current_reference_address (rtx branch)
648 {
649   rtx dest, seq;
650   int seq_uid;
651 
652   if (! INSN_ADDRESSES_SET_P ())
653     return 0;
654 
655   seq = NEXT_INSN (PREV_INSN (branch));
656   seq_uid = INSN_UID (seq);
657   if (!JUMP_P (branch))
658     /* This can happen for example on the PA; the objective is to know the
659        offset to address something in front of the start of the function.
660        Thus, we can treat it like a backward branch.
661        We assume here that FUNCTION_BOUNDARY / BITS_PER_UNIT is larger than
662        any alignment we'd encounter, so we skip the call to align_fuzz.  */
663     return insn_current_address;
664   dest = JUMP_LABEL (branch);
665 
666   /* BRANCH has no proper alignment chain set, so use SEQ.
667      BRANCH also has no INSN_SHUID.  */
668   if (INSN_SHUID (seq) < INSN_SHUID (dest))
669     {
670       /* Forward branch.  */
671       return (insn_last_address + insn_lengths[seq_uid]
672 	      - align_fuzz (seq, dest, length_unit_log, ~0));
673     }
674   else
675     {
676       /* Backward branch.  */
677       return (insn_current_address
678 	      + align_fuzz (dest, seq, length_unit_log, ~0));
679     }
680 }
681 #endif /* HAVE_ATTR_length */
682 
683 /* Compute branch alignments based on frequency information in the
684    CFG.  */
685 
686 unsigned int
687 compute_alignments (void)
688 {
689   int log, max_skip, max_log;
690   basic_block bb;
691   int freq_max = 0;
692   int freq_threshold = 0;
693 
694   if (label_align)
695     {
696       free (label_align);
697       label_align = 0;
698     }
699 
700   max_labelno = max_label_num ();
701   min_labelno = get_first_label_num ();
702   label_align = XCNEWVEC (struct label_alignment, max_labelno - min_labelno + 1);
703 
704   /* If not optimizing or optimizing for size, don't assign any alignments.  */
705   if (! optimize || optimize_function_for_size_p (cfun))
706     return 0;
707 
708   if (dump_file)
709     {
710       dump_flow_info (dump_file, TDF_DETAILS);
711       flow_loops_dump (dump_file, NULL, 1);
712       loop_optimizer_init (AVOID_CFG_MODIFICATIONS);
713     }
714   FOR_EACH_BB (bb)
715     if (bb->frequency > freq_max)
716       freq_max = bb->frequency;
717   freq_threshold = freq_max / PARAM_VALUE (PARAM_ALIGN_THRESHOLD);
718 
719   if (dump_file)
720     fprintf(dump_file, "freq_max: %i\n",freq_max);
721   FOR_EACH_BB (bb)
722     {
723       rtx label = BB_HEAD (bb);
724       int fallthru_frequency = 0, branch_frequency = 0, has_fallthru = 0;
725       edge e;
726       edge_iterator ei;
727 
728       if (!LABEL_P (label)
729 	  || optimize_bb_for_size_p (bb))
730 	{
731 	  if (dump_file)
732 	    fprintf(dump_file, "BB %4i freq %4i loop %2i loop_depth %2i skipped.\n",
733 		    bb->index, bb->frequency, bb->loop_father->num, bb->loop_depth);
734 	  continue;
735 	}
736       max_log = LABEL_ALIGN (label);
737       max_skip = LABEL_ALIGN_MAX_SKIP;
738 
739       FOR_EACH_EDGE (e, ei, bb->preds)
740 	{
741 	  if (e->flags & EDGE_FALLTHRU)
742 	    has_fallthru = 1, fallthru_frequency += EDGE_FREQUENCY (e);
743 	  else
744 	    branch_frequency += EDGE_FREQUENCY (e);
745 	}
746       if (dump_file)
747 	{
748 	  fprintf(dump_file, "BB %4i freq %4i loop %2i loop_depth %2i fall %4i branch %4i",
749 		  bb->index, bb->frequency, bb->loop_father->num,
750 		  bb->loop_depth,
751 		  fallthru_frequency, branch_frequency);
752 	  if (!bb->loop_father->inner && bb->loop_father->num)
753 	    fprintf (dump_file, " inner_loop");
754 	  if (bb->loop_father->header == bb)
755 	    fprintf (dump_file, " loop_header");
756 	  fprintf (dump_file, "\n");
757 	}
758 
759       /* There are two purposes to align block with no fallthru incoming edge:
760 	 1) to avoid fetch stalls when branch destination is near cache boundary
761 	 2) to improve cache efficiency in case the previous block is not executed
762 	    (so it does not need to be in the cache).
763 
764 	 We to catch first case, we align frequently executed blocks.
765 	 To catch the second, we align blocks that are executed more frequently
766 	 than the predecessor and the predecessor is likely to not be executed
767 	 when function is called.  */
768 
769       if (!has_fallthru
770 	  && (branch_frequency > freq_threshold
771 	      || (bb->frequency > bb->prev_bb->frequency * 10
772 		  && (bb->prev_bb->frequency
773 		      <= ENTRY_BLOCK_PTR->frequency / 2))))
774 	{
775 	  log = JUMP_ALIGN (label);
776 	  if (dump_file)
777 	    fprintf(dump_file, "  jump alignment added.\n");
778 	  if (max_log < log)
779 	    {
780 	      max_log = log;
781 	      max_skip = JUMP_ALIGN_MAX_SKIP;
782 	    }
783 	}
784       /* In case block is frequent and reached mostly by non-fallthru edge,
785 	 align it.  It is most likely a first block of loop.  */
786       if (has_fallthru
787 	  && optimize_bb_for_speed_p (bb)
788 	  && branch_frequency + fallthru_frequency > freq_threshold
789 	  && (branch_frequency
790 	      > fallthru_frequency * PARAM_VALUE (PARAM_ALIGN_LOOP_ITERATIONS)))
791 	{
792 	  log = LOOP_ALIGN (label);
793 	  if (dump_file)
794 	    fprintf(dump_file, "  internal loop alignment added.\n");
795 	  if (max_log < log)
796 	    {
797 	      max_log = log;
798 	      max_skip = LOOP_ALIGN_MAX_SKIP;
799 	    }
800 	}
801       LABEL_TO_ALIGNMENT (label) = max_log;
802       LABEL_TO_MAX_SKIP (label) = max_skip;
803     }
804 
805   if (dump_file)
806     {
807       loop_optimizer_finalize ();
808       free_dominance_info (CDI_DOMINATORS);
809     }
810   return 0;
811 }
812 
813 struct rtl_opt_pass pass_compute_alignments =
814 {
815  {
816   RTL_PASS,
817   "alignments",                         /* name */
818   NULL,                                 /* gate */
819   compute_alignments,                   /* execute */
820   NULL,                                 /* sub */
821   NULL,                                 /* next */
822   0,                                    /* static_pass_number */
823   TV_NONE,                              /* tv_id */
824   0,                                    /* properties_required */
825   0,                                    /* properties_provided */
826   0,                                    /* properties_destroyed */
827   0,                                    /* todo_flags_start */
828   TODO_dump_func | TODO_verify_rtl_sharing
829   | TODO_ggc_collect                    /* todo_flags_finish */
830  }
831 };
832 
833 
834 /* Make a pass over all insns and compute their actual lengths by shortening
835    any branches of variable length if possible.  */
836 
837 /* shorten_branches might be called multiple times:  for example, the SH
838    port splits out-of-range conditional branches in MACHINE_DEPENDENT_REORG.
839    In order to do this, it needs proper length information, which it obtains
840    by calling shorten_branches.  This cannot be collapsed with
841    shorten_branches itself into a single pass unless we also want to integrate
842    reorg.c, since the branch splitting exposes new instructions with delay
843    slots.  */
844 
845 void
846 shorten_branches (rtx first ATTRIBUTE_UNUSED)
847 {
848   rtx insn;
849   int max_uid;
850   int i;
851   int max_log;
852   int max_skip;
853 #ifdef HAVE_ATTR_length
854 #define MAX_CODE_ALIGN 16
855   rtx seq;
856   int something_changed = 1;
857   char *varying_length;
858   rtx body;
859   int uid;
860   rtx align_tab[MAX_CODE_ALIGN];
861 
862 #endif
863 
864   /* Compute maximum UID and allocate label_align / uid_shuid.  */
865   max_uid = get_max_uid ();
866 
867   /* Free uid_shuid before reallocating it.  */
868   free (uid_shuid);
869 
870   uid_shuid = XNEWVEC (int, max_uid);
871 
872   if (max_labelno != max_label_num ())
873     {
874       int old = max_labelno;
875       int n_labels;
876       int n_old_labels;
877 
878       max_labelno = max_label_num ();
879 
880       n_labels = max_labelno - min_labelno + 1;
881       n_old_labels = old - min_labelno + 1;
882 
883       label_align = XRESIZEVEC (struct label_alignment, label_align, n_labels);
884 
885       /* Range of labels grows monotonically in the function.  Failing here
886          means that the initialization of array got lost.  */
887       gcc_assert (n_old_labels <= n_labels);
888 
889       memset (label_align + n_old_labels, 0,
890 	      (n_labels - n_old_labels) * sizeof (struct label_alignment));
891     }
892 
893   /* Initialize label_align and set up uid_shuid to be strictly
894      monotonically rising with insn order.  */
895   /* We use max_log here to keep track of the maximum alignment we want to
896      impose on the next CODE_LABEL (or the current one if we are processing
897      the CODE_LABEL itself).  */
898 
899   max_log = 0;
900   max_skip = 0;
901 
902   for (insn = get_insns (), i = 1; insn; insn = NEXT_INSN (insn))
903     {
904       int log;
905 
906       INSN_SHUID (insn) = i++;
907       if (INSN_P (insn))
908 	continue;
909 
910       if (LABEL_P (insn))
911 	{
912 	  rtx next;
913 	  bool next_is_jumptable;
914 
915 	  /* Merge in alignments computed by compute_alignments.  */
916 	  log = LABEL_TO_ALIGNMENT (insn);
917 	  if (max_log < log)
918 	    {
919 	      max_log = log;
920 	      max_skip = LABEL_TO_MAX_SKIP (insn);
921 	    }
922 
923 	  next = next_nonnote_insn (insn);
924 	  next_is_jumptable = next && JUMP_TABLE_DATA_P (next);
925 	  if (!next_is_jumptable)
926 	    {
927 	      log = LABEL_ALIGN (insn);
928 	      if (max_log < log)
929 		{
930 		  max_log = log;
931 		  max_skip = LABEL_ALIGN_MAX_SKIP;
932 		}
933 	    }
934 	  /* ADDR_VECs only take room if read-only data goes into the text
935 	     section.  */
936 	  if ((JUMP_TABLES_IN_TEXT_SECTION
937 	       || readonly_data_section == text_section)
938 	      && next_is_jumptable)
939 	    {
940 	      log = ADDR_VEC_ALIGN (next);
941 	      if (max_log < log)
942 		{
943 		  max_log = log;
944 		  max_skip = LABEL_ALIGN_MAX_SKIP;
945 		}
946 	    }
947 	  LABEL_TO_ALIGNMENT (insn) = max_log;
948 	  LABEL_TO_MAX_SKIP (insn) = max_skip;
949 	  max_log = 0;
950 	  max_skip = 0;
951 	}
952       else if (BARRIER_P (insn))
953 	{
954 	  rtx label;
955 
956 	  for (label = insn; label && ! INSN_P (label);
957 	       label = NEXT_INSN (label))
958 	    if (LABEL_P (label))
959 	      {
960 		log = LABEL_ALIGN_AFTER_BARRIER (insn);
961 		if (max_log < log)
962 		  {
963 		    max_log = log;
964 		    max_skip = LABEL_ALIGN_AFTER_BARRIER_MAX_SKIP;
965 		  }
966 		break;
967 	      }
968 	}
969     }
970 #ifdef HAVE_ATTR_length
971 
972   /* Allocate the rest of the arrays.  */
973   insn_lengths = XNEWVEC (int, max_uid);
974   insn_lengths_max_uid = max_uid;
975   /* Syntax errors can lead to labels being outside of the main insn stream.
976      Initialize insn_addresses, so that we get reproducible results.  */
977   INSN_ADDRESSES_ALLOC (max_uid);
978 
979   varying_length = XCNEWVEC (char, max_uid);
980 
981   /* Initialize uid_align.  We scan instructions
982      from end to start, and keep in align_tab[n] the last seen insn
983      that does an alignment of at least n+1, i.e. the successor
984      in the alignment chain for an insn that does / has a known
985      alignment of n.  */
986   uid_align = XCNEWVEC (rtx, max_uid);
987 
988   for (i = MAX_CODE_ALIGN; --i >= 0;)
989     align_tab[i] = NULL_RTX;
990   seq = get_last_insn ();
991   for (; seq; seq = PREV_INSN (seq))
992     {
993       int uid = INSN_UID (seq);
994       int log;
995       log = (LABEL_P (seq) ? LABEL_TO_ALIGNMENT (seq) : 0);
996       uid_align[uid] = align_tab[0];
997       if (log)
998 	{
999 	  /* Found an alignment label.  */
1000 	  uid_align[uid] = align_tab[log];
1001 	  for (i = log - 1; i >= 0; i--)
1002 	    align_tab[i] = seq;
1003 	}
1004     }
1005 #ifdef CASE_VECTOR_SHORTEN_MODE
1006   if (optimize)
1007     {
1008       /* Look for ADDR_DIFF_VECs, and initialize their minimum and maximum
1009          label fields.  */
1010 
1011       int min_shuid = INSN_SHUID (get_insns ()) - 1;
1012       int max_shuid = INSN_SHUID (get_last_insn ()) + 1;
1013       int rel;
1014 
1015       for (insn = first; insn != 0; insn = NEXT_INSN (insn))
1016 	{
1017 	  rtx min_lab = NULL_RTX, max_lab = NULL_RTX, pat;
1018 	  int len, i, min, max, insn_shuid;
1019 	  int min_align;
1020 	  addr_diff_vec_flags flags;
1021 
1022 	  if (!JUMP_P (insn)
1023 	      || GET_CODE (PATTERN (insn)) != ADDR_DIFF_VEC)
1024 	    continue;
1025 	  pat = PATTERN (insn);
1026 	  len = XVECLEN (pat, 1);
1027 	  gcc_assert (len > 0);
1028 	  min_align = MAX_CODE_ALIGN;
1029 	  for (min = max_shuid, max = min_shuid, i = len - 1; i >= 0; i--)
1030 	    {
1031 	      rtx lab = XEXP (XVECEXP (pat, 1, i), 0);
1032 	      int shuid = INSN_SHUID (lab);
1033 	      if (shuid < min)
1034 		{
1035 		  min = shuid;
1036 		  min_lab = lab;
1037 		}
1038 	      if (shuid > max)
1039 		{
1040 		  max = shuid;
1041 		  max_lab = lab;
1042 		}
1043 	      if (min_align > LABEL_TO_ALIGNMENT (lab))
1044 		min_align = LABEL_TO_ALIGNMENT (lab);
1045 	    }
1046 	  XEXP (pat, 2) = gen_rtx_LABEL_REF (Pmode, min_lab);
1047 	  XEXP (pat, 3) = gen_rtx_LABEL_REF (Pmode, max_lab);
1048 	  insn_shuid = INSN_SHUID (insn);
1049 	  rel = INSN_SHUID (XEXP (XEXP (pat, 0), 0));
1050 	  memset (&flags, 0, sizeof (flags));
1051 	  flags.min_align = min_align;
1052 	  flags.base_after_vec = rel > insn_shuid;
1053 	  flags.min_after_vec  = min > insn_shuid;
1054 	  flags.max_after_vec  = max > insn_shuid;
1055 	  flags.min_after_base = min > rel;
1056 	  flags.max_after_base = max > rel;
1057 	  ADDR_DIFF_VEC_FLAGS (pat) = flags;
1058 	}
1059     }
1060 #endif /* CASE_VECTOR_SHORTEN_MODE */
1061 
1062   /* Compute initial lengths, addresses, and varying flags for each insn.  */
1063   for (insn_current_address = 0, insn = first;
1064        insn != 0;
1065        insn_current_address += insn_lengths[uid], insn = NEXT_INSN (insn))
1066     {
1067       uid = INSN_UID (insn);
1068 
1069       insn_lengths[uid] = 0;
1070 
1071       if (LABEL_P (insn))
1072 	{
1073 	  int log = LABEL_TO_ALIGNMENT (insn);
1074 	  if (log)
1075 	    {
1076 	      int align = 1 << log;
1077 	      int new_address = (insn_current_address + align - 1) & -align;
1078 	      insn_lengths[uid] = new_address - insn_current_address;
1079 	    }
1080 	}
1081 
1082       INSN_ADDRESSES (uid) = insn_current_address + insn_lengths[uid];
1083 
1084       if (NOTE_P (insn) || BARRIER_P (insn)
1085 	  || LABEL_P (insn) || DEBUG_INSN_P(insn))
1086 	continue;
1087       if (INSN_DELETED_P (insn))
1088 	continue;
1089 
1090       body = PATTERN (insn);
1091       if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
1092 	{
1093 	  /* This only takes room if read-only data goes into the text
1094 	     section.  */
1095 	  if (JUMP_TABLES_IN_TEXT_SECTION
1096 	      || readonly_data_section == text_section)
1097 	    insn_lengths[uid] = (XVECLEN (body,
1098 					  GET_CODE (body) == ADDR_DIFF_VEC)
1099 				 * GET_MODE_SIZE (GET_MODE (body)));
1100 	  /* Alignment is handled by ADDR_VEC_ALIGN.  */
1101 	}
1102       else if (GET_CODE (body) == ASM_INPUT || asm_noperands (body) >= 0)
1103 	insn_lengths[uid] = asm_insn_count (body) * insn_default_length (insn);
1104       else if (GET_CODE (body) == SEQUENCE)
1105 	{
1106 	  int i;
1107 	  int const_delay_slots;
1108 #ifdef DELAY_SLOTS
1109 	  const_delay_slots = const_num_delay_slots (XVECEXP (body, 0, 0));
1110 #else
1111 	  const_delay_slots = 0;
1112 #endif
1113 	  /* Inside a delay slot sequence, we do not do any branch shortening
1114 	     if the shortening could change the number of delay slots
1115 	     of the branch.  */
1116 	  for (i = 0; i < XVECLEN (body, 0); i++)
1117 	    {
1118 	      rtx inner_insn = XVECEXP (body, 0, i);
1119 	      int inner_uid = INSN_UID (inner_insn);
1120 	      int inner_length;
1121 
1122 	      if (GET_CODE (body) == ASM_INPUT
1123 		  || asm_noperands (PATTERN (XVECEXP (body, 0, i))) >= 0)
1124 		inner_length = (asm_insn_count (PATTERN (inner_insn))
1125 				* insn_default_length (inner_insn));
1126 	      else
1127 		inner_length = insn_default_length (inner_insn);
1128 
1129 	      insn_lengths[inner_uid] = inner_length;
1130 	      if (const_delay_slots)
1131 		{
1132 		  if ((varying_length[inner_uid]
1133 		       = insn_variable_length_p (inner_insn)) != 0)
1134 		    varying_length[uid] = 1;
1135 		  INSN_ADDRESSES (inner_uid) = (insn_current_address
1136 						+ insn_lengths[uid]);
1137 		}
1138 	      else
1139 		varying_length[inner_uid] = 0;
1140 	      insn_lengths[uid] += inner_length;
1141 	    }
1142 	}
1143       else if (GET_CODE (body) != USE && GET_CODE (body) != CLOBBER)
1144 	{
1145 	  insn_lengths[uid] = insn_default_length (insn);
1146 	  varying_length[uid] = insn_variable_length_p (insn);
1147 	}
1148 
1149       /* If needed, do any adjustment.  */
1150 #ifdef ADJUST_INSN_LENGTH
1151       ADJUST_INSN_LENGTH (insn, insn_lengths[uid]);
1152       if (insn_lengths[uid] < 0)
1153 	fatal_insn ("negative insn length", insn);
1154 #endif
1155     }
1156 
1157   /* Now loop over all the insns finding varying length insns.  For each,
1158      get the current insn length.  If it has changed, reflect the change.
1159      When nothing changes for a full pass, we are done.  */
1160 
1161   while (something_changed)
1162     {
1163       something_changed = 0;
1164       insn_current_align = MAX_CODE_ALIGN - 1;
1165       for (insn_current_address = 0, insn = first;
1166 	   insn != 0;
1167 	   insn = NEXT_INSN (insn))
1168 	{
1169 	  int new_length;
1170 #ifdef ADJUST_INSN_LENGTH
1171 	  int tmp_length;
1172 #endif
1173 	  int length_align;
1174 
1175 	  uid = INSN_UID (insn);
1176 
1177 	  if (LABEL_P (insn))
1178 	    {
1179 	      int log = LABEL_TO_ALIGNMENT (insn);
1180 	      if (log > insn_current_align)
1181 		{
1182 		  int align = 1 << log;
1183 		  int new_address= (insn_current_address + align - 1) & -align;
1184 		  insn_lengths[uid] = new_address - insn_current_address;
1185 		  insn_current_align = log;
1186 		  insn_current_address = new_address;
1187 		}
1188 	      else
1189 		insn_lengths[uid] = 0;
1190 	      INSN_ADDRESSES (uid) = insn_current_address;
1191 	      continue;
1192 	    }
1193 
1194 	  length_align = INSN_LENGTH_ALIGNMENT (insn);
1195 	  if (length_align < insn_current_align)
1196 	    insn_current_align = length_align;
1197 
1198 	  insn_last_address = INSN_ADDRESSES (uid);
1199 	  INSN_ADDRESSES (uid) = insn_current_address;
1200 
1201 #ifdef CASE_VECTOR_SHORTEN_MODE
1202 	  if (optimize && JUMP_P (insn)
1203 	      && GET_CODE (PATTERN (insn)) == ADDR_DIFF_VEC)
1204 	    {
1205 	      rtx body = PATTERN (insn);
1206 	      int old_length = insn_lengths[uid];
1207 	      rtx rel_lab = XEXP (XEXP (body, 0), 0);
1208 	      rtx min_lab = XEXP (XEXP (body, 2), 0);
1209 	      rtx max_lab = XEXP (XEXP (body, 3), 0);
1210 	      int rel_addr = INSN_ADDRESSES (INSN_UID (rel_lab));
1211 	      int min_addr = INSN_ADDRESSES (INSN_UID (min_lab));
1212 	      int max_addr = INSN_ADDRESSES (INSN_UID (max_lab));
1213 	      rtx prev;
1214 	      int rel_align = 0;
1215 	      addr_diff_vec_flags flags;
1216 
1217 	      /* Avoid automatic aggregate initialization.  */
1218 	      flags = ADDR_DIFF_VEC_FLAGS (body);
1219 
1220 	      /* Try to find a known alignment for rel_lab.  */
1221 	      for (prev = rel_lab;
1222 		   prev
1223 		   && ! insn_lengths[INSN_UID (prev)]
1224 		   && ! (varying_length[INSN_UID (prev)] & 1);
1225 		   prev = PREV_INSN (prev))
1226 		if (varying_length[INSN_UID (prev)] & 2)
1227 		  {
1228 		    rel_align = LABEL_TO_ALIGNMENT (prev);
1229 		    break;
1230 		  }
1231 
1232 	      /* See the comment on addr_diff_vec_flags in rtl.h for the
1233 		 meaning of the flags values.  base: REL_LAB   vec: INSN  */
1234 	      /* Anything after INSN has still addresses from the last
1235 		 pass; adjust these so that they reflect our current
1236 		 estimate for this pass.  */
1237 	      if (flags.base_after_vec)
1238 		rel_addr += insn_current_address - insn_last_address;
1239 	      if (flags.min_after_vec)
1240 		min_addr += insn_current_address - insn_last_address;
1241 	      if (flags.max_after_vec)
1242 		max_addr += insn_current_address - insn_last_address;
1243 	      /* We want to know the worst case, i.e. lowest possible value
1244 		 for the offset of MIN_LAB.  If MIN_LAB is after REL_LAB,
1245 		 its offset is positive, and we have to be wary of code shrink;
1246 		 otherwise, it is negative, and we have to be vary of code
1247 		 size increase.  */
1248 	      if (flags.min_after_base)
1249 		{
1250 		  /* If INSN is between REL_LAB and MIN_LAB, the size
1251 		     changes we are about to make can change the alignment
1252 		     within the observed offset, therefore we have to break
1253 		     it up into two parts that are independent.  */
1254 		  if (! flags.base_after_vec && flags.min_after_vec)
1255 		    {
1256 		      min_addr -= align_fuzz (rel_lab, insn, rel_align, 0);
1257 		      min_addr -= align_fuzz (insn, min_lab, 0, 0);
1258 		    }
1259 		  else
1260 		    min_addr -= align_fuzz (rel_lab, min_lab, rel_align, 0);
1261 		}
1262 	      else
1263 		{
1264 		  if (flags.base_after_vec && ! flags.min_after_vec)
1265 		    {
1266 		      min_addr -= align_fuzz (min_lab, insn, 0, ~0);
1267 		      min_addr -= align_fuzz (insn, rel_lab, 0, ~0);
1268 		    }
1269 		  else
1270 		    min_addr -= align_fuzz (min_lab, rel_lab, 0, ~0);
1271 		}
1272 	      /* Likewise, determine the highest lowest possible value
1273 		 for the offset of MAX_LAB.  */
1274 	      if (flags.max_after_base)
1275 		{
1276 		  if (! flags.base_after_vec && flags.max_after_vec)
1277 		    {
1278 		      max_addr += align_fuzz (rel_lab, insn, rel_align, ~0);
1279 		      max_addr += align_fuzz (insn, max_lab, 0, ~0);
1280 		    }
1281 		  else
1282 		    max_addr += align_fuzz (rel_lab, max_lab, rel_align, ~0);
1283 		}
1284 	      else
1285 		{
1286 		  if (flags.base_after_vec && ! flags.max_after_vec)
1287 		    {
1288 		      max_addr += align_fuzz (max_lab, insn, 0, 0);
1289 		      max_addr += align_fuzz (insn, rel_lab, 0, 0);
1290 		    }
1291 		  else
1292 		    max_addr += align_fuzz (max_lab, rel_lab, 0, 0);
1293 		}
1294 	      PUT_MODE (body, CASE_VECTOR_SHORTEN_MODE (min_addr - rel_addr,
1295 							max_addr - rel_addr,
1296 							body));
1297 	      if (JUMP_TABLES_IN_TEXT_SECTION
1298 		  || readonly_data_section == text_section)
1299 		{
1300 		  insn_lengths[uid]
1301 		    = (XVECLEN (body, 1) * GET_MODE_SIZE (GET_MODE (body)));
1302 		  insn_current_address += insn_lengths[uid];
1303 		  if (insn_lengths[uid] != old_length)
1304 		    something_changed = 1;
1305 		}
1306 
1307 	      continue;
1308 	    }
1309 #endif /* CASE_VECTOR_SHORTEN_MODE */
1310 
1311 	  if (! (varying_length[uid]))
1312 	    {
1313 	      if (NONJUMP_INSN_P (insn)
1314 		  && GET_CODE (PATTERN (insn)) == SEQUENCE)
1315 		{
1316 		  int i;
1317 
1318 		  body = PATTERN (insn);
1319 		  for (i = 0; i < XVECLEN (body, 0); i++)
1320 		    {
1321 		      rtx inner_insn = XVECEXP (body, 0, i);
1322 		      int inner_uid = INSN_UID (inner_insn);
1323 
1324 		      INSN_ADDRESSES (inner_uid) = insn_current_address;
1325 
1326 		      insn_current_address += insn_lengths[inner_uid];
1327 		    }
1328 		}
1329 	      else
1330 		insn_current_address += insn_lengths[uid];
1331 
1332 	      continue;
1333 	    }
1334 
1335 	  if (NONJUMP_INSN_P (insn) && GET_CODE (PATTERN (insn)) == SEQUENCE)
1336 	    {
1337 	      int i;
1338 
1339 	      body = PATTERN (insn);
1340 	      new_length = 0;
1341 	      for (i = 0; i < XVECLEN (body, 0); i++)
1342 		{
1343 		  rtx inner_insn = XVECEXP (body, 0, i);
1344 		  int inner_uid = INSN_UID (inner_insn);
1345 		  int inner_length;
1346 
1347 		  INSN_ADDRESSES (inner_uid) = insn_current_address;
1348 
1349 		  /* insn_current_length returns 0 for insns with a
1350 		     non-varying length.  */
1351 		  if (! varying_length[inner_uid])
1352 		    inner_length = insn_lengths[inner_uid];
1353 		  else
1354 		    inner_length = insn_current_length (inner_insn);
1355 
1356 		  if (inner_length != insn_lengths[inner_uid])
1357 		    {
1358 		      insn_lengths[inner_uid] = inner_length;
1359 		      something_changed = 1;
1360 		    }
1361 		  insn_current_address += insn_lengths[inner_uid];
1362 		  new_length += inner_length;
1363 		}
1364 	    }
1365 	  else
1366 	    {
1367 	      new_length = insn_current_length (insn);
1368 	      insn_current_address += new_length;
1369 	    }
1370 
1371 #ifdef ADJUST_INSN_LENGTH
1372 	  /* If needed, do any adjustment.  */
1373 	  tmp_length = new_length;
1374 	  ADJUST_INSN_LENGTH (insn, new_length);
1375 	  insn_current_address += (new_length - tmp_length);
1376 #endif
1377 
1378 	  if (new_length != insn_lengths[uid])
1379 	    {
1380 	      insn_lengths[uid] = new_length;
1381 	      something_changed = 1;
1382 	    }
1383 	}
1384       /* For a non-optimizing compile, do only a single pass.  */
1385       if (!optimize)
1386 	break;
1387     }
1388 
1389   free (varying_length);
1390 
1391 #endif /* HAVE_ATTR_length */
1392 }
1393 
1394 #ifdef HAVE_ATTR_length
1395 /* Given the body of an INSN known to be generated by an ASM statement, return
1396    the number of machine instructions likely to be generated for this insn.
1397    This is used to compute its length.  */
1398 
1399 static int
1400 asm_insn_count (rtx body)
1401 {
1402   const char *templ;
1403 
1404   if (GET_CODE (body) == ASM_INPUT)
1405     templ = XSTR (body, 0);
1406   else
1407     templ = decode_asm_operands (body, NULL, NULL, NULL, NULL, NULL);
1408 
1409   return asm_str_count (templ);
1410 }
1411 #endif
1412 
1413 /* Return the number of machine instructions likely to be generated for the
1414    inline-asm template. */
1415 int
1416 asm_str_count (const char *templ)
1417 {
1418   int count = 1;
1419 
1420   if (!*templ)
1421     return 0;
1422 
1423   for (; *templ; templ++)
1424     if (IS_ASM_LOGICAL_LINE_SEPARATOR (*templ, templ)
1425 	|| *templ == '\n')
1426       count++;
1427 
1428   return count;
1429 }
1430 
1431 /* ??? This is probably the wrong place for these.  */
1432 /* Structure recording the mapping from source file and directory
1433    names at compile time to those to be embedded in debug
1434    information.  */
1435 typedef struct debug_prefix_map
1436 {
1437   const char *old_prefix;
1438   const char *new_prefix;
1439   size_t old_len;
1440   size_t new_len;
1441   struct debug_prefix_map *next;
1442 } debug_prefix_map;
1443 
1444 /* Linked list of such structures.  */
1445 debug_prefix_map *debug_prefix_maps;
1446 
1447 
1448 /* Record a debug file prefix mapping.  ARG is the argument to
1449    -fdebug-prefix-map and must be of the form OLD=NEW.  */
1450 
1451 void
1452 add_debug_prefix_map (const char *arg)
1453 {
1454   debug_prefix_map *map;
1455   const char *p;
1456 
1457   p = strchr (arg, '=');
1458   if (!p)
1459     {
1460       error ("invalid argument %qs to -fdebug-prefix-map", arg);
1461       return;
1462     }
1463   map = XNEW (debug_prefix_map);
1464   map->old_prefix = xstrndup (arg, p - arg);
1465   map->old_len = p - arg;
1466   p++;
1467   map->new_prefix = xstrdup (p);
1468   map->new_len = strlen (p);
1469   map->next = debug_prefix_maps;
1470   debug_prefix_maps = map;
1471 }
1472 
1473 /* Perform user-specified mapping of debug filename prefixes.  Return
1474    the new name corresponding to FILENAME.  */
1475 
1476 const char *
1477 remap_debug_filename (const char *filename)
1478 {
1479   debug_prefix_map *map;
1480   char *s;
1481   const char *name;
1482   size_t name_len;
1483 
1484   for (map = debug_prefix_maps; map; map = map->next)
1485     if (strncmp (filename, map->old_prefix, map->old_len) == 0)
1486       break;
1487   if (!map)
1488     return filename;
1489   name = filename + map->old_len;
1490   name_len = strlen (name) + 1;
1491   s = (char *) alloca (name_len + map->new_len);
1492   memcpy (s, map->new_prefix, map->new_len);
1493   memcpy (s + map->new_len, name, name_len);
1494   return ggc_strdup (s);
1495 }
1496 
1497 /* Return true if DWARF2 debug info can be emitted for DECL.  */
1498 
1499 static bool
1500 dwarf2_debug_info_emitted_p (tree decl)
1501 {
1502   if (write_symbols != DWARF2_DEBUG && write_symbols != VMS_AND_DWARF2_DEBUG)
1503     return false;
1504 
1505   if (DECL_IGNORED_P (decl))
1506     return false;
1507 
1508   return true;
1509 }
1510 
1511 /* Output assembler code for the start of a function,
1512    and initialize some of the variables in this file
1513    for the new function.  The label for the function and associated
1514    assembler pseudo-ops have already been output in `assemble_start_function'.
1515 
1516    FIRST is the first insn of the rtl for the function being compiled.
1517    FILE is the file to write assembler code to.
1518    OPTIMIZE is nonzero if we should eliminate redundant
1519      test and compare insns.  */
1520 
1521 void
1522 final_start_function (rtx first ATTRIBUTE_UNUSED, FILE *file,
1523 		      int optimize ATTRIBUTE_UNUSED)
1524 {
1525   block_depth = 0;
1526 
1527   this_is_asm_operands = 0;
1528 
1529   last_filename = locator_file (prologue_locator);
1530   last_linenum = locator_line (prologue_locator);
1531   last_discriminator = discriminator = 0;
1532 
1533   high_block_linenum = high_function_linenum = last_linenum;
1534 
1535   if (!DECL_IGNORED_P (current_function_decl))
1536     debug_hooks->begin_prologue (last_linenum, last_filename);
1537 
1538 #if defined (DWARF2_UNWIND_INFO) || defined (TARGET_UNWIND_INFO)
1539   if (!dwarf2_debug_info_emitted_p (current_function_decl))
1540     dwarf2out_begin_prologue (0, NULL);
1541 #endif
1542 
1543 #ifdef LEAF_REG_REMAP
1544   if (current_function_uses_only_leaf_regs)
1545     leaf_renumber_regs (first);
1546 #endif
1547 
1548   /* The Sun386i and perhaps other machines don't work right
1549      if the profiling code comes after the prologue.  */
1550 #ifdef PROFILE_BEFORE_PROLOGUE
1551   if (crtl->profile)
1552     profile_function (file);
1553 #endif /* PROFILE_BEFORE_PROLOGUE */
1554 
1555 #if defined (DWARF2_UNWIND_INFO) && defined (HAVE_prologue)
1556   if (dwarf2out_do_frame ())
1557     dwarf2out_frame_debug (NULL_RTX, false);
1558 #endif
1559 
1560   /* If debugging, assign block numbers to all of the blocks in this
1561      function.  */
1562   if (write_symbols)
1563     {
1564       reemit_insn_block_notes ();
1565       number_blocks (current_function_decl);
1566       /* We never actually put out begin/end notes for the top-level
1567 	 block in the function.  But, conceptually, that block is
1568 	 always needed.  */
1569       TREE_ASM_WRITTEN (DECL_INITIAL (current_function_decl)) = 1;
1570     }
1571 
1572   if (warn_frame_larger_than
1573     && get_frame_size () > frame_larger_than_size)
1574   {
1575       /* Issue a warning */
1576       warning (OPT_Wframe_larger_than_,
1577                "the frame size of %wd bytes is larger than %wd bytes",
1578                get_frame_size (), frame_larger_than_size);
1579   }
1580 
1581   /* First output the function prologue: code to set up the stack frame.  */
1582   targetm.asm_out.function_prologue (file, get_frame_size ());
1583 
1584   /* If the machine represents the prologue as RTL, the profiling code must
1585      be emitted when NOTE_INSN_PROLOGUE_END is scanned.  */
1586 #ifdef HAVE_prologue
1587   if (! HAVE_prologue)
1588 #endif
1589     profile_after_prologue (file);
1590 }
1591 
1592 static void
1593 profile_after_prologue (FILE *file ATTRIBUTE_UNUSED)
1594 {
1595 #ifndef PROFILE_BEFORE_PROLOGUE
1596   if (crtl->profile)
1597     profile_function (file);
1598 #endif /* not PROFILE_BEFORE_PROLOGUE */
1599 }
1600 
1601 static void
1602 profile_function (FILE *file ATTRIBUTE_UNUSED)
1603 {
1604 #ifndef NO_PROFILE_COUNTERS
1605 # define NO_PROFILE_COUNTERS	0
1606 #endif
1607 #ifdef ASM_OUTPUT_REG_PUSH
1608   rtx sval = NULL, chain = NULL;
1609 
1610   if (cfun->returns_struct)
1611     sval = targetm.calls.struct_value_rtx (TREE_TYPE (current_function_decl),
1612 					   true);
1613   if (cfun->static_chain_decl)
1614     chain = targetm.calls.static_chain (current_function_decl, true);
1615 #endif /* ASM_OUTPUT_REG_PUSH */
1616 
1617   if (! NO_PROFILE_COUNTERS)
1618     {
1619       int align = MIN (BIGGEST_ALIGNMENT, LONG_TYPE_SIZE);
1620       switch_to_section (data_section);
1621       ASM_OUTPUT_ALIGN (file, floor_log2 (align / BITS_PER_UNIT));
1622       targetm.asm_out.internal_label (file, "LP", current_function_funcdef_no);
1623       assemble_integer (const0_rtx, LONG_TYPE_SIZE / BITS_PER_UNIT, align, 1);
1624     }
1625 
1626   switch_to_section (current_function_section ());
1627 
1628 #ifdef ASM_OUTPUT_REG_PUSH
1629   if (sval && REG_P (sval))
1630     ASM_OUTPUT_REG_PUSH (file, REGNO (sval));
1631   if (chain && REG_P (chain))
1632     ASM_OUTPUT_REG_PUSH (file, REGNO (chain));
1633 #endif
1634 
1635   FUNCTION_PROFILER (file, current_function_funcdef_no);
1636 
1637 #ifdef ASM_OUTPUT_REG_PUSH
1638   if (chain && REG_P (chain))
1639     ASM_OUTPUT_REG_POP (file, REGNO (chain));
1640   if (sval && REG_P (sval))
1641     ASM_OUTPUT_REG_POP (file, REGNO (sval));
1642 #endif
1643 }
1644 
1645 /* Output assembler code for the end of a function.
1646    For clarity, args are same as those of `final_start_function'
1647    even though not all of them are needed.  */
1648 
1649 void
1650 final_end_function (void)
1651 {
1652   app_disable ();
1653 
1654   if (!DECL_IGNORED_P (current_function_decl))
1655     debug_hooks->end_function (high_function_linenum);
1656 
1657   /* Finally, output the function epilogue:
1658      code to restore the stack frame and return to the caller.  */
1659   targetm.asm_out.function_epilogue (asm_out_file, get_frame_size ());
1660 
1661   /* And debug output.  */
1662   if (!DECL_IGNORED_P (current_function_decl))
1663     debug_hooks->end_epilogue (last_linenum, last_filename);
1664 
1665 #if defined (DWARF2_UNWIND_INFO)
1666   if (!dwarf2_debug_info_emitted_p (current_function_decl)
1667       && dwarf2out_do_frame ())
1668     dwarf2out_end_epilogue (last_linenum, last_filename);
1669 #endif
1670 }
1671 
1672 /* Output assembler code for some insns: all or part of a function.
1673    For description of args, see `final_start_function', above.  */
1674 
1675 void
1676 final (rtx first, FILE *file, int optimize)
1677 {
1678   rtx insn;
1679   int max_uid = 0;
1680   int seen = 0;
1681 
1682   last_ignored_compare = 0;
1683 
1684   for (insn = first; insn; insn = NEXT_INSN (insn))
1685     {
1686       if (INSN_UID (insn) > max_uid)       /* Find largest UID.  */
1687 	max_uid = INSN_UID (insn);
1688 #ifdef HAVE_cc0
1689       /* If CC tracking across branches is enabled, record the insn which
1690 	 jumps to each branch only reached from one place.  */
1691       if (optimize && JUMP_P (insn))
1692 	{
1693 	  rtx lab = JUMP_LABEL (insn);
1694 	  if (lab && LABEL_NUSES (lab) == 1)
1695 	    {
1696 	      LABEL_REFS (lab) = insn;
1697 	    }
1698 	}
1699 #endif
1700     }
1701 
1702   init_recog ();
1703 
1704   CC_STATUS_INIT;
1705 
1706   /* Output the insns.  */
1707   for (insn = first; insn;)
1708     {
1709 #ifdef HAVE_ATTR_length
1710       if ((unsigned) INSN_UID (insn) >= INSN_ADDRESSES_SIZE ())
1711 	{
1712 	  /* This can be triggered by bugs elsewhere in the compiler if
1713 	     new insns are created after init_insn_lengths is called.  */
1714 	  gcc_assert (NOTE_P (insn));
1715 	  insn_current_address = -1;
1716 	}
1717       else
1718 	insn_current_address = INSN_ADDRESSES (INSN_UID (insn));
1719 #endif /* HAVE_ATTR_length */
1720 
1721       insn = final_scan_insn (insn, file, optimize, 0, &seen);
1722     }
1723 }
1724 
1725 const char *
1726 get_insn_template (int code, rtx insn)
1727 {
1728   switch (insn_data[code].output_format)
1729     {
1730     case INSN_OUTPUT_FORMAT_SINGLE:
1731       return insn_data[code].output.single;
1732     case INSN_OUTPUT_FORMAT_MULTI:
1733       return insn_data[code].output.multi[which_alternative];
1734     case INSN_OUTPUT_FORMAT_FUNCTION:
1735       gcc_assert (insn);
1736       return (*insn_data[code].output.function) (recog_data.operand, insn);
1737 
1738     default:
1739       gcc_unreachable ();
1740     }
1741 }
1742 
1743 /* Emit the appropriate declaration for an alternate-entry-point
1744    symbol represented by INSN, to FILE.  INSN is a CODE_LABEL with
1745    LABEL_KIND != LABEL_NORMAL.
1746 
1747    The case fall-through in this function is intentional.  */
1748 static void
1749 output_alternate_entry_point (FILE *file, rtx insn)
1750 {
1751   const char *name = LABEL_NAME (insn);
1752 
1753   switch (LABEL_KIND (insn))
1754     {
1755     case LABEL_WEAK_ENTRY:
1756 #ifdef ASM_WEAKEN_LABEL
1757       ASM_WEAKEN_LABEL (file, name);
1758 #endif
1759     case LABEL_GLOBAL_ENTRY:
1760       targetm.asm_out.globalize_label (file, name);
1761     case LABEL_STATIC_ENTRY:
1762 #ifdef ASM_OUTPUT_TYPE_DIRECTIVE
1763       ASM_OUTPUT_TYPE_DIRECTIVE (file, name, "function");
1764 #endif
1765       ASM_OUTPUT_LABEL (file, name);
1766       break;
1767 
1768     case LABEL_NORMAL:
1769     default:
1770       gcc_unreachable ();
1771     }
1772 }
1773 
1774 /* Given a CALL_INSN, find and return the nested CALL. */
1775 static rtx
1776 call_from_call_insn (rtx insn)
1777 {
1778   rtx x;
1779   gcc_assert (CALL_P (insn));
1780   x = PATTERN (insn);
1781 
1782   while (GET_CODE (x) != CALL)
1783     {
1784       switch (GET_CODE (x))
1785 	{
1786 	default:
1787 	  gcc_unreachable ();
1788 	case COND_EXEC:
1789 	  x = COND_EXEC_CODE (x);
1790 	  break;
1791 	case PARALLEL:
1792 	  x = XVECEXP (x, 0, 0);
1793 	  break;
1794 	case SET:
1795 	  x = XEXP (x, 1);
1796 	  break;
1797 	}
1798     }
1799   return x;
1800 }
1801 
1802 /* The final scan for one insn, INSN.
1803    Args are same as in `final', except that INSN
1804    is the insn being scanned.
1805    Value returned is the next insn to be scanned.
1806 
1807    NOPEEPHOLES is the flag to disallow peephole processing (currently
1808    used for within delayed branch sequence output).
1809 
1810    SEEN is used to track the end of the prologue, for emitting
1811    debug information.  We force the emission of a line note after
1812    both NOTE_INSN_PROLOGUE_END and NOTE_INSN_FUNCTION_BEG, or
1813    at the beginning of the second basic block, whichever comes
1814    first.  */
1815 
1816 rtx
1817 final_scan_insn (rtx insn, FILE *file, int optimize ATTRIBUTE_UNUSED,
1818 		 int nopeepholes ATTRIBUTE_UNUSED, int *seen)
1819 {
1820 #ifdef HAVE_cc0
1821   rtx set;
1822 #endif
1823   rtx next;
1824 
1825   insn_counter++;
1826 
1827   /* Ignore deleted insns.  These can occur when we split insns (due to a
1828      template of "#") while not optimizing.  */
1829   if (INSN_DELETED_P (insn))
1830     return NEXT_INSN (insn);
1831 
1832   switch (GET_CODE (insn))
1833     {
1834     case NOTE:
1835       switch (NOTE_KIND (insn))
1836 	{
1837 	case NOTE_INSN_DELETED:
1838 	  break;
1839 
1840 	case NOTE_INSN_SWITCH_TEXT_SECTIONS:
1841 	  in_cold_section_p = !in_cold_section_p;
1842 #ifdef DWARF2_UNWIND_INFO
1843 	  if (dwarf2out_do_frame ())
1844 	    dwarf2out_switch_text_section ();
1845 	  else
1846 #endif
1847 	  if (!DECL_IGNORED_P (current_function_decl))
1848 	    debug_hooks->switch_text_section ();
1849 
1850 	  switch_to_section (current_function_section ());
1851 	  break;
1852 
1853 	case NOTE_INSN_BASIC_BLOCK:
1854 #ifdef TARGET_UNWIND_INFO
1855 	  targetm.asm_out.unwind_emit (asm_out_file, insn);
1856 #endif
1857 
1858 	  if (flag_debug_asm)
1859 	    fprintf (asm_out_file, "\t%s basic block %d\n",
1860 		     ASM_COMMENT_START, NOTE_BASIC_BLOCK (insn)->index);
1861 
1862 	  if ((*seen & (SEEN_EMITTED | SEEN_BB)) == SEEN_BB)
1863 	    {
1864 	      *seen |= SEEN_EMITTED;
1865 	      force_source_line = true;
1866 	    }
1867 	  else
1868 	    *seen |= SEEN_BB;
1869 
1870           discriminator = NOTE_BASIC_BLOCK (insn)->discriminator;
1871 
1872 	  break;
1873 
1874 	case NOTE_INSN_EH_REGION_BEG:
1875 	  ASM_OUTPUT_DEBUG_LABEL (asm_out_file, "LEHB",
1876 				  NOTE_EH_HANDLER (insn));
1877 	  break;
1878 
1879 	case NOTE_INSN_EH_REGION_END:
1880 	  ASM_OUTPUT_DEBUG_LABEL (asm_out_file, "LEHE",
1881 				  NOTE_EH_HANDLER (insn));
1882 	  break;
1883 
1884 	case NOTE_INSN_PROLOGUE_END:
1885 	  targetm.asm_out.function_end_prologue (file);
1886 	  profile_after_prologue (file);
1887 
1888 	  if ((*seen & (SEEN_EMITTED | SEEN_NOTE)) == SEEN_NOTE)
1889 	    {
1890 	      *seen |= SEEN_EMITTED;
1891 	      force_source_line = true;
1892 	    }
1893 	  else
1894 	    *seen |= SEEN_NOTE;
1895 
1896 	  break;
1897 
1898 	case NOTE_INSN_EPILOGUE_BEG:
1899 #if defined (DWARF2_UNWIND_INFO) && defined (HAVE_epilogue)
1900 	  if (dwarf2out_do_frame ())
1901 	    dwarf2out_begin_epilogue (insn);
1902 #endif
1903 	  targetm.asm_out.function_begin_epilogue (file);
1904 	  break;
1905 
1906 	case NOTE_INSN_CFA_RESTORE_STATE:
1907 #if defined (DWARF2_UNWIND_INFO)
1908 	  dwarf2out_frame_debug_restore_state ();
1909 #endif
1910 	  break;
1911 
1912 	case NOTE_INSN_FUNCTION_BEG:
1913 	  app_disable ();
1914 	  if (!DECL_IGNORED_P (current_function_decl))
1915 	    debug_hooks->end_prologue (last_linenum, last_filename);
1916 
1917 	  if ((*seen & (SEEN_EMITTED | SEEN_NOTE)) == SEEN_NOTE)
1918 	    {
1919 	      *seen |= SEEN_EMITTED;
1920 	      force_source_line = true;
1921 	    }
1922 	  else
1923 	    *seen |= SEEN_NOTE;
1924 
1925 	  break;
1926 
1927 	case NOTE_INSN_BLOCK_BEG:
1928 	  if (debug_info_level == DINFO_LEVEL_NORMAL
1929 	      || debug_info_level == DINFO_LEVEL_VERBOSE
1930 	      || write_symbols == DWARF2_DEBUG
1931 	      || write_symbols == VMS_AND_DWARF2_DEBUG
1932 	      || write_symbols == VMS_DEBUG)
1933 	    {
1934 	      int n = BLOCK_NUMBER (NOTE_BLOCK (insn));
1935 
1936 	      app_disable ();
1937 	      ++block_depth;
1938 	      high_block_linenum = last_linenum;
1939 
1940 	      /* Output debugging info about the symbol-block beginning.  */
1941 	      if (!DECL_IGNORED_P (current_function_decl))
1942 		debug_hooks->begin_block (last_linenum, n);
1943 
1944 	      /* Mark this block as output.  */
1945 	      TREE_ASM_WRITTEN (NOTE_BLOCK (insn)) = 1;
1946 	    }
1947 	  if (write_symbols == DBX_DEBUG
1948 	      || write_symbols == SDB_DEBUG)
1949 	    {
1950 	      location_t *locus_ptr
1951 		= block_nonartificial_location (NOTE_BLOCK (insn));
1952 
1953 	      if (locus_ptr != NULL)
1954 		{
1955 		  override_filename = LOCATION_FILE (*locus_ptr);
1956 		  override_linenum = LOCATION_LINE (*locus_ptr);
1957 		}
1958 	    }
1959 	  break;
1960 
1961 	case NOTE_INSN_BLOCK_END:
1962 	  if (debug_info_level == DINFO_LEVEL_NORMAL
1963 	      || debug_info_level == DINFO_LEVEL_VERBOSE
1964 	      || write_symbols == DWARF2_DEBUG
1965 	      || write_symbols == VMS_AND_DWARF2_DEBUG
1966 	      || write_symbols == VMS_DEBUG)
1967 	    {
1968 	      int n = BLOCK_NUMBER (NOTE_BLOCK (insn));
1969 
1970 	      app_disable ();
1971 
1972 	      /* End of a symbol-block.  */
1973 	      --block_depth;
1974 	      gcc_assert (block_depth >= 0);
1975 
1976 	      if (!DECL_IGNORED_P (current_function_decl))
1977 		debug_hooks->end_block (high_block_linenum, n);
1978 	    }
1979 	  if (write_symbols == DBX_DEBUG
1980 	      || write_symbols == SDB_DEBUG)
1981 	    {
1982 	      tree outer_block = BLOCK_SUPERCONTEXT (NOTE_BLOCK (insn));
1983 	      location_t *locus_ptr
1984 		= block_nonartificial_location (outer_block);
1985 
1986 	      if (locus_ptr != NULL)
1987 		{
1988 		  override_filename = LOCATION_FILE (*locus_ptr);
1989 		  override_linenum = LOCATION_LINE (*locus_ptr);
1990 		}
1991 	      else
1992 		{
1993 		  override_filename = NULL;
1994 		  override_linenum = 0;
1995 		}
1996 	    }
1997 	  break;
1998 
1999 	case NOTE_INSN_DELETED_LABEL:
2000 	  /* Emit the label.  We may have deleted the CODE_LABEL because
2001 	     the label could be proved to be unreachable, though still
2002 	     referenced (in the form of having its address taken.  */
2003 	  ASM_OUTPUT_DEBUG_LABEL (file, "L", CODE_LABEL_NUMBER (insn));
2004 	  break;
2005 
2006 	case NOTE_INSN_VAR_LOCATION:
2007 	  if (!DECL_IGNORED_P (current_function_decl))
2008 	    debug_hooks->var_location (insn);
2009 	  break;
2010 
2011 	default:
2012 	  gcc_unreachable ();
2013 	  break;
2014 	}
2015       break;
2016 
2017     case BARRIER:
2018 #if defined (DWARF2_UNWIND_INFO)
2019       if (dwarf2out_do_frame ())
2020 	dwarf2out_frame_debug (insn, false);
2021 #endif
2022       break;
2023 
2024     case CODE_LABEL:
2025       /* The target port might emit labels in the output function for
2026 	 some insn, e.g. sh.c output_branchy_insn.  */
2027       if (CODE_LABEL_NUMBER (insn) <= max_labelno)
2028 	{
2029 	  int align = LABEL_TO_ALIGNMENT (insn);
2030 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
2031 	  int max_skip = LABEL_TO_MAX_SKIP (insn);
2032 #endif
2033 
2034 	  if (align && NEXT_INSN (insn))
2035 	    {
2036 #ifdef ASM_OUTPUT_MAX_SKIP_ALIGN
2037 	      ASM_OUTPUT_MAX_SKIP_ALIGN (file, align, max_skip);
2038 #else
2039 #ifdef ASM_OUTPUT_ALIGN_WITH_NOP
2040               ASM_OUTPUT_ALIGN_WITH_NOP (file, align);
2041 #else
2042 	      ASM_OUTPUT_ALIGN (file, align);
2043 #endif
2044 #endif
2045 	    }
2046 	}
2047 #ifdef HAVE_cc0
2048       CC_STATUS_INIT;
2049 #endif
2050 
2051       if (!DECL_IGNORED_P (current_function_decl) && LABEL_NAME (insn))
2052 	debug_hooks->label (insn);
2053 
2054       app_disable ();
2055 
2056       next = next_nonnote_insn (insn);
2057       /* If this label is followed by a jump-table, make sure we put
2058 	 the label in the read-only section.  Also possibly write the
2059 	 label and jump table together.  */
2060       if (next != 0 && JUMP_TABLE_DATA_P (next))
2061 	{
2062 #if defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC)
2063 	  /* In this case, the case vector is being moved by the
2064 	     target, so don't output the label at all.  Leave that
2065 	     to the back end macros.  */
2066 #else
2067 	  if (! JUMP_TABLES_IN_TEXT_SECTION)
2068 	    {
2069 	      int log_align;
2070 
2071 	      switch_to_section (targetm.asm_out.function_rodata_section
2072 				 (current_function_decl));
2073 
2074 #ifdef ADDR_VEC_ALIGN
2075 	      log_align = ADDR_VEC_ALIGN (next);
2076 #else
2077 	      log_align = exact_log2 (BIGGEST_ALIGNMENT / BITS_PER_UNIT);
2078 #endif
2079 	      ASM_OUTPUT_ALIGN (file, log_align);
2080 	    }
2081 	  else
2082 	    switch_to_section (current_function_section ());
2083 
2084 #ifdef ASM_OUTPUT_CASE_LABEL
2085 	  ASM_OUTPUT_CASE_LABEL (file, "L", CODE_LABEL_NUMBER (insn),
2086 				 next);
2087 #else
2088 	  targetm.asm_out.internal_label (file, "L", CODE_LABEL_NUMBER (insn));
2089 #endif
2090 #endif
2091 	  break;
2092 	}
2093       if (LABEL_ALT_ENTRY_P (insn))
2094 	output_alternate_entry_point (file, insn);
2095       else
2096 	targetm.asm_out.internal_label (file, "L", CODE_LABEL_NUMBER (insn));
2097       break;
2098 
2099     default:
2100       {
2101 	rtx body = PATTERN (insn);
2102 	int insn_code_number;
2103 	const char *templ;
2104 	bool is_stmt;
2105 
2106 	/* Reset this early so it is correct for ASM statements.  */
2107 	current_insn_predicate = NULL_RTX;
2108 
2109 	/* An INSN, JUMP_INSN or CALL_INSN.
2110 	   First check for special kinds that recog doesn't recognize.  */
2111 
2112 	if (GET_CODE (body) == USE /* These are just declarations.  */
2113 	    || GET_CODE (body) == CLOBBER)
2114 	  break;
2115 
2116 #ifdef HAVE_cc0
2117 	{
2118 	  /* If there is a REG_CC_SETTER note on this insn, it means that
2119 	     the setting of the condition code was done in the delay slot
2120 	     of the insn that branched here.  So recover the cc status
2121 	     from the insn that set it.  */
2122 
2123 	  rtx note = find_reg_note (insn, REG_CC_SETTER, NULL_RTX);
2124 	  if (note)
2125 	    {
2126 	      NOTICE_UPDATE_CC (PATTERN (XEXP (note, 0)), XEXP (note, 0));
2127 	      cc_prev_status = cc_status;
2128 	    }
2129 	}
2130 #endif
2131 
2132 	/* Detect insns that are really jump-tables
2133 	   and output them as such.  */
2134 
2135 	if (GET_CODE (body) == ADDR_VEC || GET_CODE (body) == ADDR_DIFF_VEC)
2136 	  {
2137 #if !(defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC))
2138 	    int vlen, idx;
2139 #endif
2140 
2141 	    if (! JUMP_TABLES_IN_TEXT_SECTION)
2142 	      switch_to_section (targetm.asm_out.function_rodata_section
2143 				 (current_function_decl));
2144 	    else
2145 	      switch_to_section (current_function_section ());
2146 
2147 	    app_disable ();
2148 
2149 #if defined(ASM_OUTPUT_ADDR_VEC) || defined(ASM_OUTPUT_ADDR_DIFF_VEC)
2150 	    if (GET_CODE (body) == ADDR_VEC)
2151 	      {
2152 #ifdef ASM_OUTPUT_ADDR_VEC
2153 		ASM_OUTPUT_ADDR_VEC (PREV_INSN (insn), body);
2154 #else
2155 		gcc_unreachable ();
2156 #endif
2157 	      }
2158 	    else
2159 	      {
2160 #ifdef ASM_OUTPUT_ADDR_DIFF_VEC
2161 		ASM_OUTPUT_ADDR_DIFF_VEC (PREV_INSN (insn), body);
2162 #else
2163 		gcc_unreachable ();
2164 #endif
2165 	      }
2166 #else
2167 	    vlen = XVECLEN (body, GET_CODE (body) == ADDR_DIFF_VEC);
2168 	    for (idx = 0; idx < vlen; idx++)
2169 	      {
2170 		if (GET_CODE (body) == ADDR_VEC)
2171 		  {
2172 #ifdef ASM_OUTPUT_ADDR_VEC_ELT
2173 		    ASM_OUTPUT_ADDR_VEC_ELT
2174 		      (file, CODE_LABEL_NUMBER (XEXP (XVECEXP (body, 0, idx), 0)));
2175 #else
2176 		    gcc_unreachable ();
2177 #endif
2178 		  }
2179 		else
2180 		  {
2181 #ifdef ASM_OUTPUT_ADDR_DIFF_ELT
2182 		    ASM_OUTPUT_ADDR_DIFF_ELT
2183 		      (file,
2184 		       body,
2185 		       CODE_LABEL_NUMBER (XEXP (XVECEXP (body, 1, idx), 0)),
2186 		       CODE_LABEL_NUMBER (XEXP (XEXP (body, 0), 0)));
2187 #else
2188 		    gcc_unreachable ();
2189 #endif
2190 		  }
2191 	      }
2192 #ifdef ASM_OUTPUT_CASE_END
2193 	    ASM_OUTPUT_CASE_END (file,
2194 				 CODE_LABEL_NUMBER (PREV_INSN (insn)),
2195 				 insn);
2196 #endif
2197 #endif
2198 
2199 	    switch_to_section (current_function_section ());
2200 
2201 	    break;
2202 	  }
2203 	/* Output this line note if it is the first or the last line
2204 	   note in a row.  */
2205 	if (!DECL_IGNORED_P (current_function_decl)
2206 	    && notice_source_line (insn, &is_stmt))
2207 	  (*debug_hooks->source_line) (last_linenum, last_filename,
2208 				       last_discriminator, is_stmt);
2209 
2210 	if (GET_CODE (body) == ASM_INPUT)
2211 	  {
2212 	    const char *string = XSTR (body, 0);
2213 
2214 	    /* There's no telling what that did to the condition codes.  */
2215 	    CC_STATUS_INIT;
2216 
2217 	    if (string[0])
2218 	      {
2219 		expanded_location loc;
2220 
2221 		app_enable ();
2222 		loc = expand_location (ASM_INPUT_SOURCE_LOCATION (body));
2223 		if (*loc.file && loc.line)
2224 		  fprintf (asm_out_file, "%s %i \"%s\" 1\n",
2225 			   ASM_COMMENT_START, loc.line, loc.file);
2226 		fprintf (asm_out_file, "\t%s\n", string);
2227 #if HAVE_AS_LINE_ZERO
2228 		if (*loc.file && loc.line)
2229 		  fprintf (asm_out_file, "%s 0 \"\" 2\n", ASM_COMMENT_START);
2230 #endif
2231 	      }
2232 	    break;
2233 	  }
2234 
2235 	/* Detect `asm' construct with operands.  */
2236 	if (asm_noperands (body) >= 0)
2237 	  {
2238 	    unsigned int noperands = asm_noperands (body);
2239 	    rtx *ops = XALLOCAVEC (rtx, noperands);
2240 	    const char *string;
2241 	    location_t loc;
2242 	    expanded_location expanded;
2243 
2244 	    /* Make sure we flush any queued register saves in case this
2245 	       clobbers affected registers.  */
2246 	    if (dwarf2out_do_frame ())
2247 	      dwarf2out_frame_debug (insn, false);
2248 
2249 	    /* There's no telling what that did to the condition codes.  */
2250 	    CC_STATUS_INIT;
2251 
2252 	    /* Get out the operand values.  */
2253 	    string = decode_asm_operands (body, ops, NULL, NULL, NULL, &loc);
2254 	    /* Inhibit dying on what would otherwise be compiler bugs.  */
2255 	    insn_noperands = noperands;
2256 	    this_is_asm_operands = insn;
2257 	    expanded = expand_location (loc);
2258 
2259 #ifdef FINAL_PRESCAN_INSN
2260 	    FINAL_PRESCAN_INSN (insn, ops, insn_noperands);
2261 #endif
2262 
2263 	    /* Output the insn using them.  */
2264 	    if (string[0])
2265 	      {
2266 		app_enable ();
2267 		if (expanded.file && expanded.line)
2268 		  fprintf (asm_out_file, "%s %i \"%s\" 1\n",
2269 			   ASM_COMMENT_START, expanded.line, expanded.file);
2270 	        output_asm_insn (string, ops);
2271 #if HAVE_AS_LINE_ZERO
2272 		if (expanded.file && expanded.line)
2273 		  fprintf (asm_out_file, "%s 0 \"\" 2\n", ASM_COMMENT_START);
2274 #endif
2275 	      }
2276 
2277 	    if (targetm.asm_out.final_postscan_insn)
2278 	      targetm.asm_out.final_postscan_insn (file, insn, ops,
2279 						   insn_noperands);
2280 
2281 	    this_is_asm_operands = 0;
2282 	    break;
2283 	  }
2284 
2285 	app_disable ();
2286 
2287 	if (GET_CODE (body) == SEQUENCE)
2288 	  {
2289 	    /* A delayed-branch sequence */
2290 	    int i;
2291 
2292 	    final_sequence = body;
2293 
2294 	    /* Record the delay slots' frame information before the branch.
2295 	       This is needed for delayed calls: see execute_cfa_program().  */
2296 #if defined (DWARF2_UNWIND_INFO)
2297 	    if (dwarf2out_do_frame ())
2298 	      for (i = 1; i < XVECLEN (body, 0); i++)
2299 		dwarf2out_frame_debug (XVECEXP (body, 0, i), false);
2300 #endif
2301 
2302 	    /* The first insn in this SEQUENCE might be a JUMP_INSN that will
2303 	       force the restoration of a comparison that was previously
2304 	       thought unnecessary.  If that happens, cancel this sequence
2305 	       and cause that insn to be restored.  */
2306 
2307 	    next = final_scan_insn (XVECEXP (body, 0, 0), file, 0, 1, seen);
2308 	    if (next != XVECEXP (body, 0, 1))
2309 	      {
2310 		final_sequence = 0;
2311 		return next;
2312 	      }
2313 
2314 	    for (i = 1; i < XVECLEN (body, 0); i++)
2315 	      {
2316 		rtx insn = XVECEXP (body, 0, i);
2317 		rtx next = NEXT_INSN (insn);
2318 		/* We loop in case any instruction in a delay slot gets
2319 		   split.  */
2320 		do
2321 		  insn = final_scan_insn (insn, file, 0, 1, seen);
2322 		while (insn != next);
2323 	      }
2324 #ifdef DBR_OUTPUT_SEQEND
2325 	    DBR_OUTPUT_SEQEND (file);
2326 #endif
2327 	    final_sequence = 0;
2328 
2329 	    /* If the insn requiring the delay slot was a CALL_INSN, the
2330 	       insns in the delay slot are actually executed before the
2331 	       called function.  Hence we don't preserve any CC-setting
2332 	       actions in these insns and the CC must be marked as being
2333 	       clobbered by the function.  */
2334 	    if (CALL_P (XVECEXP (body, 0, 0)))
2335 	      {
2336 		CC_STATUS_INIT;
2337 	      }
2338 	    break;
2339 	  }
2340 
2341 	/* We have a real machine instruction as rtl.  */
2342 
2343 	body = PATTERN (insn);
2344 
2345 #ifdef HAVE_cc0
2346 	set = single_set (insn);
2347 
2348 	/* Check for redundant test and compare instructions
2349 	   (when the condition codes are already set up as desired).
2350 	   This is done only when optimizing; if not optimizing,
2351 	   it should be possible for the user to alter a variable
2352 	   with the debugger in between statements
2353 	   and the next statement should reexamine the variable
2354 	   to compute the condition codes.  */
2355 
2356 	if (optimize)
2357 	  {
2358 	    if (set
2359 		&& GET_CODE (SET_DEST (set)) == CC0
2360 		&& insn != last_ignored_compare)
2361 	      {
2362 		rtx src1, src2;
2363 		if (GET_CODE (SET_SRC (set)) == SUBREG)
2364 		  SET_SRC (set) = alter_subreg (&SET_SRC (set));
2365 
2366 		src1 = SET_SRC (set);
2367 		src2 = NULL_RTX;
2368 		if (GET_CODE (SET_SRC (set)) == COMPARE)
2369 		  {
2370 		    if (GET_CODE (XEXP (SET_SRC (set), 0)) == SUBREG)
2371 		      XEXP (SET_SRC (set), 0)
2372 			= alter_subreg (&XEXP (SET_SRC (set), 0));
2373 		    if (GET_CODE (XEXP (SET_SRC (set), 1)) == SUBREG)
2374 		      XEXP (SET_SRC (set), 1)
2375 			= alter_subreg (&XEXP (SET_SRC (set), 1));
2376 		    if (XEXP (SET_SRC (set), 1)
2377 			== CONST0_RTX (GET_MODE (XEXP (SET_SRC (set), 0))))
2378 		      src2 = XEXP (SET_SRC (set), 0);
2379 		  }
2380 		if ((cc_status.value1 != 0
2381 		     && rtx_equal_p (src1, cc_status.value1))
2382 		    || (cc_status.value2 != 0
2383 			&& rtx_equal_p (src1, cc_status.value2))
2384 		    || (src2 != 0 && cc_status.value1 != 0
2385 		        && rtx_equal_p (src2, cc_status.value1))
2386 		    || (src2 != 0 && cc_status.value2 != 0
2387 			&& rtx_equal_p (src2, cc_status.value2)))
2388 		  {
2389 		    /* Don't delete insn if it has an addressing side-effect.  */
2390 		    if (! FIND_REG_INC_NOTE (insn, NULL_RTX)
2391 			/* or if anything in it is volatile.  */
2392 			&& ! volatile_refs_p (PATTERN (insn)))
2393 		      {
2394 			/* We don't really delete the insn; just ignore it.  */
2395 			last_ignored_compare = insn;
2396 			break;
2397 		      }
2398 		  }
2399 	      }
2400 	  }
2401 
2402 	/* If this is a conditional branch, maybe modify it
2403 	   if the cc's are in a nonstandard state
2404 	   so that it accomplishes the same thing that it would
2405 	   do straightforwardly if the cc's were set up normally.  */
2406 
2407 	if (cc_status.flags != 0
2408 	    && JUMP_P (insn)
2409 	    && GET_CODE (body) == SET
2410 	    && SET_DEST (body) == pc_rtx
2411 	    && GET_CODE (SET_SRC (body)) == IF_THEN_ELSE
2412 	    && COMPARISON_P (XEXP (SET_SRC (body), 0))
2413 	    && XEXP (XEXP (SET_SRC (body), 0), 0) == cc0_rtx)
2414 	  {
2415 	    /* This function may alter the contents of its argument
2416 	       and clear some of the cc_status.flags bits.
2417 	       It may also return 1 meaning condition now always true
2418 	       or -1 meaning condition now always false
2419 	       or 2 meaning condition nontrivial but altered.  */
2420 	    int result = alter_cond (XEXP (SET_SRC (body), 0));
2421 	    /* If condition now has fixed value, replace the IF_THEN_ELSE
2422 	       with its then-operand or its else-operand.  */
2423 	    if (result == 1)
2424 	      SET_SRC (body) = XEXP (SET_SRC (body), 1);
2425 	    if (result == -1)
2426 	      SET_SRC (body) = XEXP (SET_SRC (body), 2);
2427 
2428 	    /* The jump is now either unconditional or a no-op.
2429 	       If it has become a no-op, don't try to output it.
2430 	       (It would not be recognized.)  */
2431 	    if (SET_SRC (body) == pc_rtx)
2432 	      {
2433 	        delete_insn (insn);
2434 		break;
2435 	      }
2436 	    else if (GET_CODE (SET_SRC (body)) == RETURN)
2437 	      /* Replace (set (pc) (return)) with (return).  */
2438 	      PATTERN (insn) = body = SET_SRC (body);
2439 
2440 	    /* Rerecognize the instruction if it has changed.  */
2441 	    if (result != 0)
2442 	      INSN_CODE (insn) = -1;
2443 	  }
2444 
2445 	/* If this is a conditional trap, maybe modify it if the cc's
2446 	   are in a nonstandard state so that it accomplishes the same
2447 	   thing that it would do straightforwardly if the cc's were
2448 	   set up normally.  */
2449 	if (cc_status.flags != 0
2450 	    && NONJUMP_INSN_P (insn)
2451 	    && GET_CODE (body) == TRAP_IF
2452 	    && COMPARISON_P (TRAP_CONDITION (body))
2453 	    && XEXP (TRAP_CONDITION (body), 0) == cc0_rtx)
2454 	  {
2455 	    /* This function may alter the contents of its argument
2456 	       and clear some of the cc_status.flags bits.
2457 	       It may also return 1 meaning condition now always true
2458 	       or -1 meaning condition now always false
2459 	       or 2 meaning condition nontrivial but altered.  */
2460 	    int result = alter_cond (TRAP_CONDITION (body));
2461 
2462 	    /* If TRAP_CONDITION has become always false, delete the
2463 	       instruction.  */
2464 	    if (result == -1)
2465 	      {
2466 		delete_insn (insn);
2467 		break;
2468 	      }
2469 
2470 	    /* If TRAP_CONDITION has become always true, replace
2471 	       TRAP_CONDITION with const_true_rtx.  */
2472 	    if (result == 1)
2473 	      TRAP_CONDITION (body) = const_true_rtx;
2474 
2475 	    /* Rerecognize the instruction if it has changed.  */
2476 	    if (result != 0)
2477 	      INSN_CODE (insn) = -1;
2478 	  }
2479 
2480 	/* Make same adjustments to instructions that examine the
2481 	   condition codes without jumping and instructions that
2482 	   handle conditional moves (if this machine has either one).  */
2483 
2484 	if (cc_status.flags != 0
2485 	    && set != 0)
2486 	  {
2487 	    rtx cond_rtx, then_rtx, else_rtx;
2488 
2489 	    if (!JUMP_P (insn)
2490 		&& GET_CODE (SET_SRC (set)) == IF_THEN_ELSE)
2491 	      {
2492 		cond_rtx = XEXP (SET_SRC (set), 0);
2493 		then_rtx = XEXP (SET_SRC (set), 1);
2494 		else_rtx = XEXP (SET_SRC (set), 2);
2495 	      }
2496 	    else
2497 	      {
2498 		cond_rtx = SET_SRC (set);
2499 		then_rtx = const_true_rtx;
2500 		else_rtx = const0_rtx;
2501 	      }
2502 
2503 	    switch (GET_CODE (cond_rtx))
2504 	      {
2505 	      case GTU:
2506 	      case GT:
2507 	      case LTU:
2508 	      case LT:
2509 	      case GEU:
2510 	      case GE:
2511 	      case LEU:
2512 	      case LE:
2513 	      case EQ:
2514 	      case NE:
2515 		{
2516 		  int result;
2517 		  if (XEXP (cond_rtx, 0) != cc0_rtx)
2518 		    break;
2519 		  result = alter_cond (cond_rtx);
2520 		  if (result == 1)
2521 		    validate_change (insn, &SET_SRC (set), then_rtx, 0);
2522 		  else if (result == -1)
2523 		    validate_change (insn, &SET_SRC (set), else_rtx, 0);
2524 		  else if (result == 2)
2525 		    INSN_CODE (insn) = -1;
2526 		  if (SET_DEST (set) == SET_SRC (set))
2527 		    delete_insn (insn);
2528 		}
2529 		break;
2530 
2531 	      default:
2532 		break;
2533 	      }
2534 	  }
2535 
2536 #endif
2537 
2538 #ifdef HAVE_peephole
2539 	/* Do machine-specific peephole optimizations if desired.  */
2540 
2541 	if (optimize && !flag_no_peephole && !nopeepholes)
2542 	  {
2543 	    rtx next = peephole (insn);
2544 	    /* When peepholing, if there were notes within the peephole,
2545 	       emit them before the peephole.  */
2546 	    if (next != 0 && next != NEXT_INSN (insn))
2547 	      {
2548 		rtx note, prev = PREV_INSN (insn);
2549 
2550 		for (note = NEXT_INSN (insn); note != next;
2551 		     note = NEXT_INSN (note))
2552 		  final_scan_insn (note, file, optimize, nopeepholes, seen);
2553 
2554 		/* Put the notes in the proper position for a later
2555 		   rescan.  For example, the SH target can do this
2556 		   when generating a far jump in a delayed branch
2557 		   sequence.  */
2558 		note = NEXT_INSN (insn);
2559 		PREV_INSN (note) = prev;
2560 		NEXT_INSN (prev) = note;
2561 		NEXT_INSN (PREV_INSN (next)) = insn;
2562 		PREV_INSN (insn) = PREV_INSN (next);
2563 		NEXT_INSN (insn) = next;
2564 		PREV_INSN (next) = insn;
2565 	      }
2566 
2567 	    /* PEEPHOLE might have changed this.  */
2568 	    body = PATTERN (insn);
2569 	  }
2570 #endif
2571 
2572 	/* Try to recognize the instruction.
2573 	   If successful, verify that the operands satisfy the
2574 	   constraints for the instruction.  Crash if they don't,
2575 	   since `reload' should have changed them so that they do.  */
2576 
2577 	insn_code_number = recog_memoized (insn);
2578 	cleanup_subreg_operands (insn);
2579 
2580 	/* Dump the insn in the assembly for debugging.  */
2581 	if (flag_dump_rtl_in_asm)
2582 	  {
2583 	    print_rtx_head = ASM_COMMENT_START;
2584 	    print_rtl_single (asm_out_file, insn);
2585 	    print_rtx_head = "";
2586 	  }
2587 
2588 	if (! constrain_operands_cached (1))
2589 	  fatal_insn_not_found (insn);
2590 
2591 	/* Some target machines need to prescan each insn before
2592 	   it is output.  */
2593 
2594 #ifdef FINAL_PRESCAN_INSN
2595 	FINAL_PRESCAN_INSN (insn, recog_data.operand, recog_data.n_operands);
2596 #endif
2597 
2598 	if (targetm.have_conditional_execution ()
2599 	    && GET_CODE (PATTERN (insn)) == COND_EXEC)
2600 	  current_insn_predicate = COND_EXEC_TEST (PATTERN (insn));
2601 
2602 #ifdef HAVE_cc0
2603 	cc_prev_status = cc_status;
2604 
2605 	/* Update `cc_status' for this instruction.
2606 	   The instruction's output routine may change it further.
2607 	   If the output routine for a jump insn needs to depend
2608 	   on the cc status, it should look at cc_prev_status.  */
2609 
2610 	NOTICE_UPDATE_CC (body, insn);
2611 #endif
2612 
2613 	current_output_insn = debug_insn = insn;
2614 
2615 #if defined (DWARF2_UNWIND_INFO)
2616 	if (CALL_P (insn) && dwarf2out_do_frame ())
2617 	  dwarf2out_frame_debug (insn, false);
2618 #endif
2619 
2620 	/* Find the proper template for this insn.  */
2621 	templ = get_insn_template (insn_code_number, insn);
2622 
2623 	/* If the C code returns 0, it means that it is a jump insn
2624 	   which follows a deleted test insn, and that test insn
2625 	   needs to be reinserted.  */
2626 	if (templ == 0)
2627 	  {
2628 	    rtx prev;
2629 
2630 	    gcc_assert (prev_nonnote_insn (insn) == last_ignored_compare);
2631 
2632 	    /* We have already processed the notes between the setter and
2633 	       the user.  Make sure we don't process them again, this is
2634 	       particularly important if one of the notes is a block
2635 	       scope note or an EH note.  */
2636 	    for (prev = insn;
2637 		 prev != last_ignored_compare;
2638 		 prev = PREV_INSN (prev))
2639 	      {
2640 		if (NOTE_P (prev))
2641 		  delete_insn (prev);	/* Use delete_note.  */
2642 	      }
2643 
2644 	    return prev;
2645 	  }
2646 
2647 	/* If the template is the string "#", it means that this insn must
2648 	   be split.  */
2649 	if (templ[0] == '#' && templ[1] == '\0')
2650 	  {
2651 	    rtx new_rtx = try_split (body, insn, 0);
2652 
2653 	    /* If we didn't split the insn, go away.  */
2654 	    if (new_rtx == insn && PATTERN (new_rtx) == body)
2655 	      fatal_insn ("could not split insn", insn);
2656 
2657 #ifdef HAVE_ATTR_length
2658 	    /* This instruction should have been split in shorten_branches,
2659 	       to ensure that we would have valid length info for the
2660 	       splitees.  */
2661 	    gcc_unreachable ();
2662 #endif
2663 
2664 	    return new_rtx;
2665 	  }
2666 
2667 #ifdef TARGET_UNWIND_INFO
2668 	/* ??? This will put the directives in the wrong place if
2669 	   get_insn_template outputs assembly directly.  However calling it
2670 	   before get_insn_template breaks if the insns is split.  */
2671 	targetm.asm_out.unwind_emit (asm_out_file, insn);
2672 #endif
2673 
2674 	if (CALL_P (insn))
2675 	  {
2676 	    rtx x = call_from_call_insn (insn);
2677 	    x = XEXP (x, 0);
2678 	    if (x && MEM_P (x) && GET_CODE (XEXP (x, 0)) == SYMBOL_REF)
2679 	      {
2680 		tree t;
2681 		x = XEXP (x, 0);
2682 		t = SYMBOL_REF_DECL (x);
2683 		if (t)
2684 		  assemble_external (t);
2685 	      }
2686 	  }
2687 
2688 	/* Output assembler code from the template.  */
2689 	output_asm_insn (templ, recog_data.operand);
2690 
2691 	/* Record point-of-call information for ICF debugging.  */
2692 	if (flag_enable_icf_debug && CALL_P (insn))
2693 	  {
2694 	    rtx x = call_from_call_insn (insn);
2695 	    x = XEXP (x, 0);
2696 	    if (x && MEM_P (x))
2697 	      {
2698 	        if (GET_CODE (XEXP (x, 0)) == SYMBOL_REF)
2699 	          {
2700 		    tree t;
2701 		    x = XEXP (x, 0);
2702 		    t = SYMBOL_REF_DECL (x);
2703 		    if (t)
2704 		      (*debug_hooks->direct_call) (t);
2705 	          }
2706 	        else
2707 	          (*debug_hooks->virtual_call) (INSN_UID (insn));
2708 	      }
2709 	  }
2710 
2711 	/* Some target machines need to postscan each insn after
2712 	   it is output.  */
2713 	if (targetm.asm_out.final_postscan_insn)
2714 	  targetm.asm_out.final_postscan_insn (file, insn, recog_data.operand,
2715 					       recog_data.n_operands);
2716 
2717 	/* If necessary, report the effect that the instruction has on
2718 	   the unwind info.   We've already done this for delay slots
2719 	   and call instructions.  */
2720 #if defined (DWARF2_UNWIND_INFO)
2721 	if (final_sequence == 0
2722 #if !defined (HAVE_prologue)
2723 	    && !ACCUMULATE_OUTGOING_ARGS
2724 #endif
2725 	    && dwarf2out_do_frame ())
2726 	  dwarf2out_frame_debug (insn, true);
2727 #endif
2728 
2729 	current_output_insn = debug_insn = 0;
2730       }
2731     }
2732   return NEXT_INSN (insn);
2733 }
2734 
2735 /* Return whether a source line note needs to be emitted before INSN.
2736    Sets IS_STMT to TRUE if the line should be marked as a possible
2737    breakpoint location.  */
2738 
2739 static bool
2740 notice_source_line (rtx insn, bool *is_stmt)
2741 {
2742   const char *filename;
2743   int linenum;
2744 
2745   if (override_filename)
2746     {
2747       filename = override_filename;
2748       linenum = override_linenum;
2749     }
2750   else
2751     {
2752       filename = insn_file (insn);
2753       linenum = insn_line (insn);
2754     }
2755 
2756   if (filename == NULL)
2757     return false;
2758 
2759   if (force_source_line
2760       || filename != last_filename
2761       || last_linenum != linenum)
2762     {
2763       force_source_line = false;
2764       last_filename = filename;
2765       last_linenum = linenum;
2766       last_discriminator = discriminator;
2767       *is_stmt = true;
2768       high_block_linenum = MAX (last_linenum, high_block_linenum);
2769       high_function_linenum = MAX (last_linenum, high_function_linenum);
2770       return true;
2771     }
2772 
2773   if (SUPPORTS_DISCRIMINATOR && last_discriminator != discriminator)
2774     {
2775       /* If the discriminator changed, but the line number did not,
2776          output the line table entry with is_stmt false so the
2777          debugger does not treat this as a breakpoint location.  */
2778       last_discriminator = discriminator;
2779       *is_stmt = false;
2780       return true;
2781     }
2782 
2783   return false;
2784 }
2785 
2786 /* For each operand in INSN, simplify (subreg (reg)) so that it refers
2787    directly to the desired hard register.  */
2788 
2789 void
2790 cleanup_subreg_operands (rtx insn)
2791 {
2792   int i;
2793   bool changed = false;
2794   extract_insn_cached (insn);
2795   for (i = 0; i < recog_data.n_operands; i++)
2796     {
2797       /* The following test cannot use recog_data.operand when testing
2798 	 for a SUBREG: the underlying object might have been changed
2799 	 already if we are inside a match_operator expression that
2800 	 matches the else clause.  Instead we test the underlying
2801 	 expression directly.  */
2802       if (GET_CODE (*recog_data.operand_loc[i]) == SUBREG)
2803 	{
2804 	  recog_data.operand[i] = alter_subreg (recog_data.operand_loc[i]);
2805 	  changed = true;
2806 	}
2807       else if (GET_CODE (recog_data.operand[i]) == PLUS
2808 	       || GET_CODE (recog_data.operand[i]) == MULT
2809 	       || MEM_P (recog_data.operand[i]))
2810 	recog_data.operand[i] = walk_alter_subreg (recog_data.operand_loc[i], &changed);
2811     }
2812 
2813   for (i = 0; i < recog_data.n_dups; i++)
2814     {
2815       if (GET_CODE (*recog_data.dup_loc[i]) == SUBREG)
2816 	{
2817 	  *recog_data.dup_loc[i] = alter_subreg (recog_data.dup_loc[i]);
2818 	  changed = true;
2819 	}
2820       else if (GET_CODE (*recog_data.dup_loc[i]) == PLUS
2821 	       || GET_CODE (*recog_data.dup_loc[i]) == MULT
2822 	       || MEM_P (*recog_data.dup_loc[i]))
2823 	*recog_data.dup_loc[i] = walk_alter_subreg (recog_data.dup_loc[i], &changed);
2824     }
2825   if (changed)
2826     df_insn_rescan (insn);
2827 }
2828 
2829 /* If X is a SUBREG, replace it with a REG or a MEM,
2830    based on the thing it is a subreg of.  */
2831 
2832 rtx
2833 alter_subreg (rtx *xp)
2834 {
2835   rtx x = *xp;
2836   rtx y = SUBREG_REG (x);
2837 
2838   /* simplify_subreg does not remove subreg from volatile references.
2839      We are required to.  */
2840   if (MEM_P (y))
2841     {
2842       int offset = SUBREG_BYTE (x);
2843 
2844       /* For paradoxical subregs on big-endian machines, SUBREG_BYTE
2845 	 contains 0 instead of the proper offset.  See simplify_subreg.  */
2846       if (offset == 0
2847 	  && GET_MODE_SIZE (GET_MODE (y)) < GET_MODE_SIZE (GET_MODE (x)))
2848         {
2849           int difference = GET_MODE_SIZE (GET_MODE (y))
2850 			   - GET_MODE_SIZE (GET_MODE (x));
2851           if (WORDS_BIG_ENDIAN)
2852             offset += (difference / UNITS_PER_WORD) * UNITS_PER_WORD;
2853           if (BYTES_BIG_ENDIAN)
2854             offset += difference % UNITS_PER_WORD;
2855         }
2856 
2857       *xp = adjust_address (y, GET_MODE (x), offset);
2858     }
2859   else
2860     {
2861       rtx new_rtx = simplify_subreg (GET_MODE (x), y, GET_MODE (y),
2862 				 SUBREG_BYTE (x));
2863 
2864       if (new_rtx != 0)
2865 	*xp = new_rtx;
2866       else if (REG_P (y))
2867 	{
2868 	  /* Simplify_subreg can't handle some REG cases, but we have to.  */
2869 	  unsigned int regno;
2870 	  HOST_WIDE_INT offset;
2871 
2872 	  regno = subreg_regno (x);
2873 	  if (subreg_lowpart_p (x))
2874 	    offset = byte_lowpart_offset (GET_MODE (x), GET_MODE (y));
2875 	  else
2876 	    offset = SUBREG_BYTE (x);
2877 	  *xp = gen_rtx_REG_offset (y, GET_MODE (x), regno, offset);
2878 	}
2879     }
2880 
2881   return *xp;
2882 }
2883 
2884 /* Do alter_subreg on all the SUBREGs contained in X.  */
2885 
2886 static rtx
2887 walk_alter_subreg (rtx *xp, bool *changed)
2888 {
2889   rtx x = *xp;
2890   switch (GET_CODE (x))
2891     {
2892     case PLUS:
2893     case MULT:
2894     case AND:
2895       XEXP (x, 0) = walk_alter_subreg (&XEXP (x, 0), changed);
2896       XEXP (x, 1) = walk_alter_subreg (&XEXP (x, 1), changed);
2897       break;
2898 
2899     case MEM:
2900     case ZERO_EXTEND:
2901       XEXP (x, 0) = walk_alter_subreg (&XEXP (x, 0), changed);
2902       break;
2903 
2904     case SUBREG:
2905       *changed = true;
2906       return alter_subreg (xp);
2907 
2908     default:
2909       break;
2910     }
2911 
2912   return *xp;
2913 }
2914 
2915 #ifdef HAVE_cc0
2916 
2917 /* Given BODY, the body of a jump instruction, alter the jump condition
2918    as required by the bits that are set in cc_status.flags.
2919    Not all of the bits there can be handled at this level in all cases.
2920 
2921    The value is normally 0.
2922    1 means that the condition has become always true.
2923    -1 means that the condition has become always false.
2924    2 means that COND has been altered.  */
2925 
2926 static int
2927 alter_cond (rtx cond)
2928 {
2929   int value = 0;
2930 
2931   if (cc_status.flags & CC_REVERSED)
2932     {
2933       value = 2;
2934       PUT_CODE (cond, swap_condition (GET_CODE (cond)));
2935     }
2936 
2937   if (cc_status.flags & CC_INVERTED)
2938     {
2939       value = 2;
2940       PUT_CODE (cond, reverse_condition (GET_CODE (cond)));
2941     }
2942 
2943   if (cc_status.flags & CC_NOT_POSITIVE)
2944     switch (GET_CODE (cond))
2945       {
2946       case LE:
2947       case LEU:
2948       case GEU:
2949 	/* Jump becomes unconditional.  */
2950 	return 1;
2951 
2952       case GT:
2953       case GTU:
2954       case LTU:
2955 	/* Jump becomes no-op.  */
2956 	return -1;
2957 
2958       case GE:
2959 	PUT_CODE (cond, EQ);
2960 	value = 2;
2961 	break;
2962 
2963       case LT:
2964 	PUT_CODE (cond, NE);
2965 	value = 2;
2966 	break;
2967 
2968       default:
2969 	break;
2970       }
2971 
2972   if (cc_status.flags & CC_NOT_NEGATIVE)
2973     switch (GET_CODE (cond))
2974       {
2975       case GE:
2976       case GEU:
2977 	/* Jump becomes unconditional.  */
2978 	return 1;
2979 
2980       case LT:
2981       case LTU:
2982 	/* Jump becomes no-op.  */
2983 	return -1;
2984 
2985       case LE:
2986       case LEU:
2987 	PUT_CODE (cond, EQ);
2988 	value = 2;
2989 	break;
2990 
2991       case GT:
2992       case GTU:
2993 	PUT_CODE (cond, NE);
2994 	value = 2;
2995 	break;
2996 
2997       default:
2998 	break;
2999       }
3000 
3001   if (cc_status.flags & CC_NO_OVERFLOW)
3002     switch (GET_CODE (cond))
3003       {
3004       case GEU:
3005 	/* Jump becomes unconditional.  */
3006 	return 1;
3007 
3008       case LEU:
3009 	PUT_CODE (cond, EQ);
3010 	value = 2;
3011 	break;
3012 
3013       case GTU:
3014 	PUT_CODE (cond, NE);
3015 	value = 2;
3016 	break;
3017 
3018       case LTU:
3019 	/* Jump becomes no-op.  */
3020 	return -1;
3021 
3022       default:
3023 	break;
3024       }
3025 
3026   if (cc_status.flags & (CC_Z_IN_NOT_N | CC_Z_IN_N))
3027     switch (GET_CODE (cond))
3028       {
3029       default:
3030 	gcc_unreachable ();
3031 
3032       case NE:
3033 	PUT_CODE (cond, cc_status.flags & CC_Z_IN_N ? GE : LT);
3034 	value = 2;
3035 	break;
3036 
3037       case EQ:
3038 	PUT_CODE (cond, cc_status.flags & CC_Z_IN_N ? LT : GE);
3039 	value = 2;
3040 	break;
3041       }
3042 
3043   if (cc_status.flags & CC_NOT_SIGNED)
3044     /* The flags are valid if signed condition operators are converted
3045        to unsigned.  */
3046     switch (GET_CODE (cond))
3047       {
3048       case LE:
3049 	PUT_CODE (cond, LEU);
3050 	value = 2;
3051 	break;
3052 
3053       case LT:
3054 	PUT_CODE (cond, LTU);
3055 	value = 2;
3056 	break;
3057 
3058       case GT:
3059 	PUT_CODE (cond, GTU);
3060 	value = 2;
3061 	break;
3062 
3063       case GE:
3064 	PUT_CODE (cond, GEU);
3065 	value = 2;
3066 	break;
3067 
3068       default:
3069 	break;
3070       }
3071 
3072   return value;
3073 }
3074 #endif
3075 
3076 /* Report inconsistency between the assembler template and the operands.
3077    In an `asm', it's the user's fault; otherwise, the compiler's fault.  */
3078 
3079 void
3080 output_operand_lossage (const char *cmsgid, ...)
3081 {
3082   char *fmt_string;
3083   char *new_message;
3084   const char *pfx_str;
3085   va_list ap;
3086 
3087   va_start (ap, cmsgid);
3088 
3089   pfx_str = this_is_asm_operands ? _("invalid 'asm': ") : "output_operand: ";
3090   asprintf (&fmt_string, "%s%s", pfx_str, _(cmsgid));
3091   vasprintf (&new_message, fmt_string, ap);
3092 
3093   if (this_is_asm_operands)
3094     error_for_asm (this_is_asm_operands, "%s", new_message);
3095   else
3096     internal_error ("%s", new_message);
3097 
3098   free (fmt_string);
3099   free (new_message);
3100   va_end (ap);
3101 }
3102 
3103 /* Output of assembler code from a template, and its subroutines.  */
3104 
3105 /* Annotate the assembly with a comment describing the pattern and
3106    alternative used.  */
3107 
3108 static void
3109 output_asm_name (void)
3110 {
3111   if (debug_insn)
3112     {
3113       int num = INSN_CODE (debug_insn);
3114       fprintf (asm_out_file, "\t%s %d\t%s",
3115 	       ASM_COMMENT_START, INSN_UID (debug_insn),
3116 	       insn_data[num].name);
3117       if (insn_data[num].n_alternatives > 1)
3118 	fprintf (asm_out_file, "/%d", which_alternative + 1);
3119 #ifdef HAVE_ATTR_length
3120       fprintf (asm_out_file, "\t[length = %d]",
3121 	       get_attr_length (debug_insn));
3122 #endif
3123       /* Clear this so only the first assembler insn
3124 	 of any rtl insn will get the special comment for -dp.  */
3125       debug_insn = 0;
3126     }
3127 }
3128 
3129 /* If OP is a REG or MEM and we can find a MEM_EXPR corresponding to it
3130    or its address, return that expr .  Set *PADDRESSP to 1 if the expr
3131    corresponds to the address of the object and 0 if to the object.  */
3132 
3133 static tree
3134 get_mem_expr_from_op (rtx op, int *paddressp)
3135 {
3136   tree expr;
3137   int inner_addressp;
3138 
3139   *paddressp = 0;
3140 
3141   if (REG_P (op))
3142     return REG_EXPR (op);
3143   else if (!MEM_P (op))
3144     return 0;
3145 
3146   if (MEM_EXPR (op) != 0)
3147     return MEM_EXPR (op);
3148 
3149   /* Otherwise we have an address, so indicate it and look at the address.  */
3150   *paddressp = 1;
3151   op = XEXP (op, 0);
3152 
3153   /* First check if we have a decl for the address, then look at the right side
3154      if it is a PLUS.  Otherwise, strip off arithmetic and keep looking.
3155      But don't allow the address to itself be indirect.  */
3156   if ((expr = get_mem_expr_from_op (op, &inner_addressp)) && ! inner_addressp)
3157     return expr;
3158   else if (GET_CODE (op) == PLUS
3159 	   && (expr = get_mem_expr_from_op (XEXP (op, 1), &inner_addressp)))
3160     return expr;
3161 
3162   while (UNARY_P (op)
3163 	 || GET_RTX_CLASS (GET_CODE (op)) == RTX_BIN_ARITH)
3164     op = XEXP (op, 0);
3165 
3166   expr = get_mem_expr_from_op (op, &inner_addressp);
3167   return inner_addressp ? 0 : expr;
3168 }
3169 
3170 /* Output operand names for assembler instructions.  OPERANDS is the
3171    operand vector, OPORDER is the order to write the operands, and NOPS
3172    is the number of operands to write.  */
3173 
3174 static void
3175 output_asm_operand_names (rtx *operands, int *oporder, int nops)
3176 {
3177   int wrote = 0;
3178   int i;
3179 
3180   for (i = 0; i < nops; i++)
3181     {
3182       int addressp;
3183       rtx op = operands[oporder[i]];
3184       tree expr = get_mem_expr_from_op (op, &addressp);
3185 
3186       fprintf (asm_out_file, "%c%s",
3187 	       wrote ? ',' : '\t', wrote ? "" : ASM_COMMENT_START);
3188       wrote = 1;
3189       if (expr)
3190 	{
3191 	  fprintf (asm_out_file, "%s",
3192 		   addressp ? "*" : "");
3193 	  print_mem_expr (asm_out_file, expr);
3194 	  wrote = 1;
3195 	}
3196       else if (REG_P (op) && ORIGINAL_REGNO (op)
3197 	       && ORIGINAL_REGNO (op) != REGNO (op))
3198 	fprintf (asm_out_file, " tmp%i", ORIGINAL_REGNO (op));
3199     }
3200 }
3201 
3202 /* Output text from TEMPLATE to the assembler output file,
3203    obeying %-directions to substitute operands taken from
3204    the vector OPERANDS.
3205 
3206    %N (for N a digit) means print operand N in usual manner.
3207    %lN means require operand N to be a CODE_LABEL or LABEL_REF
3208       and print the label name with no punctuation.
3209    %cN means require operand N to be a constant
3210       and print the constant expression with no punctuation.
3211    %aN means expect operand N to be a memory address
3212       (not a memory reference!) and print a reference
3213       to that address.
3214    %nN means expect operand N to be a constant
3215       and print a constant expression for minus the value
3216       of the operand, with no other punctuation.  */
3217 
3218 void
3219 output_asm_insn (const char *templ, rtx *operands)
3220 {
3221   const char *p;
3222   int c;
3223 #ifdef ASSEMBLER_DIALECT
3224   int dialect = 0;
3225 #endif
3226   int oporder[MAX_RECOG_OPERANDS];
3227   char opoutput[MAX_RECOG_OPERANDS];
3228   int ops = 0;
3229 
3230   /* An insn may return a null string template
3231      in a case where no assembler code is needed.  */
3232   if (*templ == 0)
3233     return;
3234 
3235   memset (opoutput, 0, sizeof opoutput);
3236   p = templ;
3237   putc ('\t', asm_out_file);
3238 
3239 #ifdef ASM_OUTPUT_OPCODE
3240   ASM_OUTPUT_OPCODE (asm_out_file, p);
3241 #endif
3242 
3243   while ((c = *p++))
3244     switch (c)
3245       {
3246       case '\n':
3247 	if (flag_verbose_asm)
3248 	  output_asm_operand_names (operands, oporder, ops);
3249 	if (flag_print_asm_name)
3250 	  output_asm_name ();
3251 
3252 	ops = 0;
3253 	memset (opoutput, 0, sizeof opoutput);
3254 
3255 	putc (c, asm_out_file);
3256 #ifdef ASM_OUTPUT_OPCODE
3257 	while ((c = *p) == '\t')
3258 	  {
3259 	    putc (c, asm_out_file);
3260 	    p++;
3261 	  }
3262 	ASM_OUTPUT_OPCODE (asm_out_file, p);
3263 #endif
3264 	break;
3265 
3266 #ifdef ASSEMBLER_DIALECT
3267       case '{':
3268 	{
3269 	  int i;
3270 
3271 	  if (dialect)
3272 	    output_operand_lossage ("nested assembly dialect alternatives");
3273 	  else
3274 	    dialect = 1;
3275 
3276 	  /* If we want the first dialect, do nothing.  Otherwise, skip
3277 	     DIALECT_NUMBER of strings ending with '|'.  */
3278 	  for (i = 0; i < dialect_number; i++)
3279 	    {
3280 	      while (*p && *p != '}' && *p++ != '|')
3281 		;
3282 	      if (*p == '}')
3283 		break;
3284 	      if (*p == '|')
3285 		p++;
3286 	    }
3287 
3288 	  if (*p == '\0')
3289 	    output_operand_lossage ("unterminated assembly dialect alternative");
3290 	}
3291 	break;
3292 
3293       case '|':
3294 	if (dialect)
3295 	  {
3296 	    /* Skip to close brace.  */
3297 	    do
3298 	      {
3299 		if (*p == '\0')
3300 		  {
3301 		    output_operand_lossage ("unterminated assembly dialect alternative");
3302 		    break;
3303 		  }
3304 	      }
3305 	    while (*p++ != '}');
3306 	    dialect = 0;
3307 	  }
3308 	else
3309 	  putc (c, asm_out_file);
3310 	break;
3311 
3312       case '}':
3313 	if (! dialect)
3314 	  putc (c, asm_out_file);
3315 	dialect = 0;
3316 	break;
3317 #endif
3318 
3319       case '%':
3320 	/* %% outputs a single %.  */
3321 	if (*p == '%')
3322 	  {
3323 	    p++;
3324 	    putc (c, asm_out_file);
3325 	  }
3326 	/* %= outputs a number which is unique to each insn in the entire
3327 	   compilation.  This is useful for making local labels that are
3328 	   referred to more than once in a given insn.  */
3329 	else if (*p == '=')
3330 	  {
3331 	    p++;
3332 	    fprintf (asm_out_file, "%d", insn_counter);
3333 	  }
3334 	/* % followed by a letter and some digits
3335 	   outputs an operand in a special way depending on the letter.
3336 	   Letters `acln' are implemented directly.
3337 	   Other letters are passed to `output_operand' so that
3338 	   the PRINT_OPERAND macro can define them.  */
3339 	else if (ISALPHA (*p))
3340 	  {
3341 	    int letter = *p++;
3342 	    unsigned long opnum;
3343 	    char *endptr;
3344 
3345 	    opnum = strtoul (p, &endptr, 10);
3346 
3347 	    if (endptr == p)
3348 	      output_operand_lossage ("operand number missing "
3349 				      "after %%-letter");
3350 	    else if (this_is_asm_operands && opnum >= insn_noperands)
3351 	      output_operand_lossage ("operand number out of range");
3352 	    else if (letter == 'l')
3353 	      output_asm_label (operands[opnum]);
3354 	    else if (letter == 'a')
3355 	      output_address (operands[opnum]);
3356 	    else if (letter == 'c')
3357 	      {
3358 		if (CONSTANT_ADDRESS_P (operands[opnum]))
3359 		  output_addr_const (asm_out_file, operands[opnum]);
3360 		else
3361 		  output_operand (operands[opnum], 'c');
3362 	      }
3363 	    else if (letter == 'n')
3364 	      {
3365 		if (CONST_INT_P (operands[opnum]))
3366 		  fprintf (asm_out_file, HOST_WIDE_INT_PRINT_DEC,
3367 			   - INTVAL (operands[opnum]));
3368 		else
3369 		  {
3370 		    putc ('-', asm_out_file);
3371 		    output_addr_const (asm_out_file, operands[opnum]);
3372 		  }
3373 	      }
3374 	    else
3375 	      output_operand (operands[opnum], letter);
3376 
3377 	    if (!opoutput[opnum])
3378 	      oporder[ops++] = opnum;
3379 	    opoutput[opnum] = 1;
3380 
3381 	    p = endptr;
3382 	    c = *p;
3383 	  }
3384 	/* % followed by a digit outputs an operand the default way.  */
3385 	else if (ISDIGIT (*p))
3386 	  {
3387 	    unsigned long opnum;
3388 	    char *endptr;
3389 
3390 	    opnum = strtoul (p, &endptr, 10);
3391 	    if (this_is_asm_operands && opnum >= insn_noperands)
3392 	      output_operand_lossage ("operand number out of range");
3393 	    else
3394 	      output_operand (operands[opnum], 0);
3395 
3396 	    if (!opoutput[opnum])
3397 	      oporder[ops++] = opnum;
3398 	    opoutput[opnum] = 1;
3399 
3400 	    p = endptr;
3401 	    c = *p;
3402 	  }
3403 	/* % followed by punctuation: output something for that
3404 	   punctuation character alone, with no operand.
3405 	   The PRINT_OPERAND macro decides what is actually done.  */
3406 #ifdef PRINT_OPERAND_PUNCT_VALID_P
3407 	else if (PRINT_OPERAND_PUNCT_VALID_P ((unsigned char) *p))
3408 	  output_operand (NULL_RTX, *p++);
3409 #endif
3410 	else
3411 	  output_operand_lossage ("invalid %%-code");
3412 	break;
3413 
3414       default:
3415 	putc (c, asm_out_file);
3416       }
3417 
3418   /* Write out the variable names for operands, if we know them.  */
3419   if (flag_verbose_asm)
3420     output_asm_operand_names (operands, oporder, ops);
3421   if (flag_print_asm_name)
3422     output_asm_name ();
3423 
3424   putc ('\n', asm_out_file);
3425 }
3426 
3427 /* Output a LABEL_REF, or a bare CODE_LABEL, as an assembler symbol.  */
3428 
3429 void
3430 output_asm_label (rtx x)
3431 {
3432   char buf[256];
3433 
3434   if (GET_CODE (x) == LABEL_REF)
3435     x = XEXP (x, 0);
3436   if (LABEL_P (x)
3437       || (NOTE_P (x)
3438 	  && NOTE_KIND (x) == NOTE_INSN_DELETED_LABEL))
3439     ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
3440   else
3441     output_operand_lossage ("'%%l' operand isn't a label");
3442 
3443   assemble_name (asm_out_file, buf);
3444 }
3445 
3446 /* Helper rtx-iteration-function for mark_symbol_refs_as_used and
3447    output_operand.  Marks SYMBOL_REFs as referenced through use of
3448    assemble_external.  */
3449 
3450 static int
3451 mark_symbol_ref_as_used (rtx *xp, void *dummy ATTRIBUTE_UNUSED)
3452 {
3453   rtx x = *xp;
3454 
3455   /* If we have a used symbol, we may have to emit assembly
3456      annotations corresponding to whether the symbol is external, weak
3457      or has non-default visibility.  */
3458   if (GET_CODE (x) == SYMBOL_REF)
3459     {
3460       tree t;
3461 
3462       t = SYMBOL_REF_DECL (x);
3463       if (t)
3464 	assemble_external (t);
3465 
3466       return -1;
3467     }
3468 
3469   return 0;
3470 }
3471 
3472 /* Marks SYMBOL_REFs in x as referenced through use of assemble_external.  */
3473 
3474 void
3475 mark_symbol_refs_as_used (rtx x)
3476 {
3477   for_each_rtx (&x, mark_symbol_ref_as_used, NULL);
3478 }
3479 
3480 /* Print operand X using machine-dependent assembler syntax.
3481    The macro PRINT_OPERAND is defined just to control this function.
3482    CODE is a non-digit that preceded the operand-number in the % spec,
3483    such as 'z' if the spec was `%z3'.  CODE is 0 if there was no char
3484    between the % and the digits.
3485    When CODE is a non-letter, X is 0.
3486 
3487    The meanings of the letters are machine-dependent and controlled
3488    by PRINT_OPERAND.  */
3489 
3490 static void
3491 output_operand (rtx x, int code ATTRIBUTE_UNUSED)
3492 {
3493   if (x && GET_CODE (x) == SUBREG)
3494     x = alter_subreg (&x);
3495 
3496   /* X must not be a pseudo reg.  */
3497   gcc_assert (!x || !REG_P (x) || REGNO (x) < FIRST_PSEUDO_REGISTER);
3498 
3499   PRINT_OPERAND (asm_out_file, x, code);
3500 
3501   if (x == NULL_RTX)
3502     return;
3503 
3504   for_each_rtx (&x, mark_symbol_ref_as_used, NULL);
3505 }
3506 
3507 /* Print a memory reference operand for address X
3508    using machine-dependent assembler syntax.
3509    The macro PRINT_OPERAND_ADDRESS exists just to control this function.  */
3510 
3511 void
3512 output_address (rtx x)
3513 {
3514   bool changed = false;
3515   walk_alter_subreg (&x, &changed);
3516   PRINT_OPERAND_ADDRESS (asm_out_file, x);
3517 }
3518 
3519 /* Print an integer constant expression in assembler syntax.
3520    Addition and subtraction are the only arithmetic
3521    that may appear in these expressions.  */
3522 
3523 void
3524 output_addr_const (FILE *file, rtx x)
3525 {
3526   char buf[256];
3527 
3528  restart:
3529   switch (GET_CODE (x))
3530     {
3531     case PC:
3532       putc ('.', file);
3533       break;
3534 
3535     case SYMBOL_REF:
3536       if (SYMBOL_REF_DECL (x))
3537 	{
3538 	  mark_decl_referenced (SYMBOL_REF_DECL (x));
3539 	  assemble_external (SYMBOL_REF_DECL (x));
3540 	}
3541 #ifdef ASM_OUTPUT_SYMBOL_REF
3542       ASM_OUTPUT_SYMBOL_REF (file, x);
3543 #else
3544       assemble_name (file, XSTR (x, 0));
3545 #endif
3546       break;
3547 
3548     case LABEL_REF:
3549       x = XEXP (x, 0);
3550       /* Fall through.  */
3551     case CODE_LABEL:
3552       ASM_GENERATE_INTERNAL_LABEL (buf, "L", CODE_LABEL_NUMBER (x));
3553 #ifdef ASM_OUTPUT_LABEL_REF
3554       ASM_OUTPUT_LABEL_REF (file, buf);
3555 #else
3556       assemble_name (file, buf);
3557 #endif
3558       break;
3559 
3560     case CONST_INT:
3561       fprintf (file, HOST_WIDE_INT_PRINT_DEC, INTVAL (x));
3562       break;
3563 
3564     case CONST:
3565       /* This used to output parentheses around the expression,
3566 	 but that does not work on the 386 (either ATT or BSD assembler).  */
3567       output_addr_const (file, XEXP (x, 0));
3568       break;
3569 
3570     case CONST_DOUBLE:
3571       if (GET_MODE (x) == VOIDmode)
3572 	{
3573 	  /* We can use %d if the number is one word and positive.  */
3574 	  if (CONST_DOUBLE_HIGH (x))
3575 	    fprintf (file, HOST_WIDE_INT_PRINT_DOUBLE_HEX,
3576 		     (unsigned HOST_WIDE_INT) CONST_DOUBLE_HIGH (x),
3577 		     (unsigned HOST_WIDE_INT) CONST_DOUBLE_LOW (x));
3578 	  else if (CONST_DOUBLE_LOW (x) < 0)
3579 	    fprintf (file, HOST_WIDE_INT_PRINT_HEX,
3580 		     (unsigned HOST_WIDE_INT) CONST_DOUBLE_LOW (x));
3581 	  else
3582 	    fprintf (file, HOST_WIDE_INT_PRINT_DEC, CONST_DOUBLE_LOW (x));
3583 	}
3584       else
3585 	/* We can't handle floating point constants;
3586 	   PRINT_OPERAND must handle them.  */
3587 	output_operand_lossage ("floating constant misused");
3588       break;
3589 
3590     case CONST_FIXED:
3591       fprintf (file, HOST_WIDE_INT_PRINT_HEX,
3592 	       (unsigned HOST_WIDE_INT) CONST_FIXED_VALUE_LOW (x));
3593       break;
3594 
3595     case PLUS:
3596       /* Some assemblers need integer constants to appear last (eg masm).  */
3597       if (CONST_INT_P (XEXP (x, 0)))
3598 	{
3599 	  output_addr_const (file, XEXP (x, 1));
3600 	  if (INTVAL (XEXP (x, 0)) >= 0)
3601 	    fprintf (file, "+");
3602 	  output_addr_const (file, XEXP (x, 0));
3603 	}
3604       else
3605 	{
3606 	  output_addr_const (file, XEXP (x, 0));
3607 	  if (!CONST_INT_P (XEXP (x, 1))
3608 	      || INTVAL (XEXP (x, 1)) >= 0)
3609 	    fprintf (file, "+");
3610 	  output_addr_const (file, XEXP (x, 1));
3611 	}
3612       break;
3613 
3614     case MINUS:
3615       /* Avoid outputting things like x-x or x+5-x,
3616 	 since some assemblers can't handle that.  */
3617       x = simplify_subtraction (x);
3618       if (GET_CODE (x) != MINUS)
3619 	goto restart;
3620 
3621       output_addr_const (file, XEXP (x, 0));
3622       fprintf (file, "-");
3623       if ((CONST_INT_P (XEXP (x, 1)) && INTVAL (XEXP (x, 1)) >= 0)
3624 	  || GET_CODE (XEXP (x, 1)) == PC
3625 	  || GET_CODE (XEXP (x, 1)) == SYMBOL_REF)
3626 	output_addr_const (file, XEXP (x, 1));
3627       else
3628 	{
3629 	  fputs (targetm.asm_out.open_paren, file);
3630 	  output_addr_const (file, XEXP (x, 1));
3631 	  fputs (targetm.asm_out.close_paren, file);
3632 	}
3633       break;
3634 
3635     case ZERO_EXTEND:
3636     case SIGN_EXTEND:
3637     case SUBREG:
3638     case TRUNCATE:
3639       output_addr_const (file, XEXP (x, 0));
3640       break;
3641 
3642     default:
3643 #ifdef OUTPUT_ADDR_CONST_EXTRA
3644       OUTPUT_ADDR_CONST_EXTRA (file, x, fail);
3645       break;
3646 
3647     fail:
3648 #endif
3649       output_operand_lossage ("invalid expression as operand");
3650     }
3651 }
3652 
3653 /* A poor man's fprintf, with the added features of %I, %R, %L, and %U.
3654    %R prints the value of REGISTER_PREFIX.
3655    %L prints the value of LOCAL_LABEL_PREFIX.
3656    %U prints the value of USER_LABEL_PREFIX.
3657    %I prints the value of IMMEDIATE_PREFIX.
3658    %O runs ASM_OUTPUT_OPCODE to transform what follows in the string.
3659    Also supported are %d, %i, %u, %x, %X, %o, %c, %s and %%.
3660 
3661    We handle alternate assembler dialects here, just like output_asm_insn.  */
3662 
3663 void
3664 asm_fprintf (FILE *file, const char *p, ...)
3665 {
3666   char buf[10];
3667   char *q, c;
3668   va_list argptr;
3669 
3670   va_start (argptr, p);
3671 
3672   buf[0] = '%';
3673 
3674   while ((c = *p++))
3675     switch (c)
3676       {
3677 #ifdef ASSEMBLER_DIALECT
3678       case '{':
3679 	{
3680 	  int i;
3681 
3682 	  /* If we want the first dialect, do nothing.  Otherwise, skip
3683 	     DIALECT_NUMBER of strings ending with '|'.  */
3684 	  for (i = 0; i < dialect_number; i++)
3685 	    {
3686 	      while (*p && *p++ != '|')
3687 		;
3688 
3689 	      if (*p == '|')
3690 		p++;
3691 	    }
3692 	}
3693 	break;
3694 
3695       case '|':
3696 	/* Skip to close brace.  */
3697 	while (*p && *p++ != '}')
3698 	  ;
3699 	break;
3700 
3701       case '}':
3702 	break;
3703 #endif
3704 
3705       case '%':
3706 	c = *p++;
3707 	q = &buf[1];
3708 	while (strchr ("-+ #0", c))
3709 	  {
3710 	    *q++ = c;
3711 	    c = *p++;
3712 	  }
3713 	while (ISDIGIT (c) || c == '.')
3714 	  {
3715 	    *q++ = c;
3716 	    c = *p++;
3717 	  }
3718 	switch (c)
3719 	  {
3720 	  case '%':
3721 	    putc ('%', file);
3722 	    break;
3723 
3724 	  case 'd':  case 'i':  case 'u':
3725 	  case 'x':  case 'X':  case 'o':
3726 	  case 'c':
3727 	    *q++ = c;
3728 	    *q = 0;
3729 	    fprintf (file, buf, va_arg (argptr, int));
3730 	    break;
3731 
3732 	  case 'w':
3733 	    /* This is a prefix to the 'd', 'i', 'u', 'x', 'X', and
3734 	       'o' cases, but we do not check for those cases.  It
3735 	       means that the value is a HOST_WIDE_INT, which may be
3736 	       either `long' or `long long'.  */
3737 	    memcpy (q, HOST_WIDE_INT_PRINT, strlen (HOST_WIDE_INT_PRINT));
3738 	    q += strlen (HOST_WIDE_INT_PRINT);
3739 	    *q++ = *p++;
3740 	    *q = 0;
3741 	    fprintf (file, buf, va_arg (argptr, HOST_WIDE_INT));
3742 	    break;
3743 
3744 	  case 'l':
3745 	    *q++ = c;
3746 #ifdef HAVE_LONG_LONG
3747 	    if (*p == 'l')
3748 	      {
3749 		*q++ = *p++;
3750 		*q++ = *p++;
3751 		*q = 0;
3752 		fprintf (file, buf, va_arg (argptr, long long));
3753 	      }
3754 	    else
3755 #endif
3756 	      {
3757 		*q++ = *p++;
3758 		*q = 0;
3759 		fprintf (file, buf, va_arg (argptr, long));
3760 	      }
3761 
3762 	    break;
3763 
3764 	  case 's':
3765 	    *q++ = c;
3766 	    *q = 0;
3767 	    fprintf (file, buf, va_arg (argptr, char *));
3768 	    break;
3769 
3770 	  case 'O':
3771 #ifdef ASM_OUTPUT_OPCODE
3772 	    ASM_OUTPUT_OPCODE (asm_out_file, p);
3773 #endif
3774 	    break;
3775 
3776 	  case 'R':
3777 #ifdef REGISTER_PREFIX
3778 	    fprintf (file, "%s", REGISTER_PREFIX);
3779 #endif
3780 	    break;
3781 
3782 	  case 'I':
3783 #ifdef IMMEDIATE_PREFIX
3784 	    fprintf (file, "%s", IMMEDIATE_PREFIX);
3785 #endif
3786 	    break;
3787 
3788 	  case 'L':
3789 #ifdef LOCAL_LABEL_PREFIX
3790 	    fprintf (file, "%s", LOCAL_LABEL_PREFIX);
3791 #endif
3792 	    break;
3793 
3794 	  case 'U':
3795 	    fputs (user_label_prefix, file);
3796 	    break;
3797 
3798 #ifdef ASM_FPRINTF_EXTENSIONS
3799 	    /* Uppercase letters are reserved for general use by asm_fprintf
3800 	       and so are not available to target specific code.  In order to
3801 	       prevent the ASM_FPRINTF_EXTENSIONS macro from using them then,
3802 	       they are defined here.  As they get turned into real extensions
3803 	       to asm_fprintf they should be removed from this list.  */
3804 	  case 'A': case 'B': case 'C': case 'D': case 'E':
3805 	  case 'F': case 'G': case 'H': case 'J': case 'K':
3806 	  case 'M': case 'N': case 'P': case 'Q': case 'S':
3807 	  case 'T': case 'V': case 'W': case 'Y': case 'Z':
3808 	    break;
3809 
3810 	  ASM_FPRINTF_EXTENSIONS (file, argptr, p)
3811 #endif
3812 	  default:
3813 	    gcc_unreachable ();
3814 	  }
3815 	break;
3816 
3817       default:
3818 	putc (c, file);
3819       }
3820   va_end (argptr);
3821 }
3822 
3823 /* Split up a CONST_DOUBLE or integer constant rtx
3824    into two rtx's for single words,
3825    storing in *FIRST the word that comes first in memory in the target
3826    and in *SECOND the other.  */
3827 
3828 void
3829 split_double (rtx value, rtx *first, rtx *second)
3830 {
3831   if (CONST_INT_P (value))
3832     {
3833       if (HOST_BITS_PER_WIDE_INT >= (2 * BITS_PER_WORD))
3834 	{
3835 	  /* In this case the CONST_INT holds both target words.
3836 	     Extract the bits from it into two word-sized pieces.
3837 	     Sign extend each half to HOST_WIDE_INT.  */
3838 	  unsigned HOST_WIDE_INT low, high;
3839 	  unsigned HOST_WIDE_INT mask, sign_bit, sign_extend;
3840 
3841 	  /* Set sign_bit to the most significant bit of a word.  */
3842 	  sign_bit = 1;
3843 	  sign_bit <<= BITS_PER_WORD - 1;
3844 
3845 	  /* Set mask so that all bits of the word are set.  We could
3846 	     have used 1 << BITS_PER_WORD instead of basing the
3847 	     calculation on sign_bit.  However, on machines where
3848 	     HOST_BITS_PER_WIDE_INT == BITS_PER_WORD, it could cause a
3849 	     compiler warning, even though the code would never be
3850 	     executed.  */
3851 	  mask = sign_bit << 1;
3852 	  mask--;
3853 
3854 	  /* Set sign_extend as any remaining bits.  */
3855 	  sign_extend = ~mask;
3856 
3857 	  /* Pick the lower word and sign-extend it.  */
3858 	  low = INTVAL (value);
3859 	  low &= mask;
3860 	  if (low & sign_bit)
3861 	    low |= sign_extend;
3862 
3863 	  /* Pick the higher word, shifted to the least significant
3864 	     bits, and sign-extend it.  */
3865 	  high = INTVAL (value);
3866 	  high >>= BITS_PER_WORD - 1;
3867 	  high >>= 1;
3868 	  high &= mask;
3869 	  if (high & sign_bit)
3870 	    high |= sign_extend;
3871 
3872 	  /* Store the words in the target machine order.  */
3873 	  if (WORDS_BIG_ENDIAN)
3874 	    {
3875 	      *first = GEN_INT (high);
3876 	      *second = GEN_INT (low);
3877 	    }
3878 	  else
3879 	    {
3880 	      *first = GEN_INT (low);
3881 	      *second = GEN_INT (high);
3882 	    }
3883 	}
3884       else
3885 	{
3886 	  /* The rule for using CONST_INT for a wider mode
3887 	     is that we regard the value as signed.
3888 	     So sign-extend it.  */
3889 	  rtx high = (INTVAL (value) < 0 ? constm1_rtx : const0_rtx);
3890 	  if (WORDS_BIG_ENDIAN)
3891 	    {
3892 	      *first = high;
3893 	      *second = value;
3894 	    }
3895 	  else
3896 	    {
3897 	      *first = value;
3898 	      *second = high;
3899 	    }
3900 	}
3901     }
3902   else if (GET_CODE (value) != CONST_DOUBLE)
3903     {
3904       if (WORDS_BIG_ENDIAN)
3905 	{
3906 	  *first = const0_rtx;
3907 	  *second = value;
3908 	}
3909       else
3910 	{
3911 	  *first = value;
3912 	  *second = const0_rtx;
3913 	}
3914     }
3915   else if (GET_MODE (value) == VOIDmode
3916 	   /* This is the old way we did CONST_DOUBLE integers.  */
3917 	   || GET_MODE_CLASS (GET_MODE (value)) == MODE_INT)
3918     {
3919       /* In an integer, the words are defined as most and least significant.
3920 	 So order them by the target's convention.  */
3921       if (WORDS_BIG_ENDIAN)
3922 	{
3923 	  *first = GEN_INT (CONST_DOUBLE_HIGH (value));
3924 	  *second = GEN_INT (CONST_DOUBLE_LOW (value));
3925 	}
3926       else
3927 	{
3928 	  *first = GEN_INT (CONST_DOUBLE_LOW (value));
3929 	  *second = GEN_INT (CONST_DOUBLE_HIGH (value));
3930 	}
3931     }
3932   else
3933     {
3934       REAL_VALUE_TYPE r;
3935       long l[2];
3936       REAL_VALUE_FROM_CONST_DOUBLE (r, value);
3937 
3938       /* Note, this converts the REAL_VALUE_TYPE to the target's
3939 	 format, splits up the floating point double and outputs
3940 	 exactly 32 bits of it into each of l[0] and l[1] --
3941 	 not necessarily BITS_PER_WORD bits.  */
3942       REAL_VALUE_TO_TARGET_DOUBLE (r, l);
3943 
3944       /* If 32 bits is an entire word for the target, but not for the host,
3945 	 then sign-extend on the host so that the number will look the same
3946 	 way on the host that it would on the target.  See for instance
3947 	 simplify_unary_operation.  The #if is needed to avoid compiler
3948 	 warnings.  */
3949 
3950 #if HOST_BITS_PER_LONG > 32
3951       if (BITS_PER_WORD < HOST_BITS_PER_LONG && BITS_PER_WORD == 32)
3952 	{
3953 	  if (l[0] & ((long) 1 << 31))
3954 	    l[0] |= ((long) (-1) << 32);
3955 	  if (l[1] & ((long) 1 << 31))
3956 	    l[1] |= ((long) (-1) << 32);
3957 	}
3958 #endif
3959 
3960       *first = GEN_INT (l[0]);
3961       *second = GEN_INT (l[1]);
3962     }
3963 }
3964 
3965 /* Return nonzero if this function has no function calls.  */
3966 
3967 int
3968 leaf_function_p (void)
3969 {
3970   rtx insn;
3971   rtx link;
3972 
3973   if (crtl->profile || profile_arc_flag)
3974     return 0;
3975 
3976   for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
3977     {
3978       if (CALL_P (insn)
3979 	  && ! SIBLING_CALL_P (insn))
3980 	return 0;
3981       if (NONJUMP_INSN_P (insn)
3982 	  && GET_CODE (PATTERN (insn)) == SEQUENCE
3983 	  && CALL_P (XVECEXP (PATTERN (insn), 0, 0))
3984 	  && ! SIBLING_CALL_P (XVECEXP (PATTERN (insn), 0, 0)))
3985 	return 0;
3986     }
3987   for (link = crtl->epilogue_delay_list;
3988        link;
3989        link = XEXP (link, 1))
3990     {
3991       insn = XEXP (link, 0);
3992 
3993       if (CALL_P (insn)
3994 	  && ! SIBLING_CALL_P (insn))
3995 	return 0;
3996       if (NONJUMP_INSN_P (insn)
3997 	  && GET_CODE (PATTERN (insn)) == SEQUENCE
3998 	  && CALL_P (XVECEXP (PATTERN (insn), 0, 0))
3999 	  && ! SIBLING_CALL_P (XVECEXP (PATTERN (insn), 0, 0)))
4000 	return 0;
4001     }
4002 
4003   return 1;
4004 }
4005 
4006 /* Return 1 if branch is a forward branch.
4007    Uses insn_shuid array, so it works only in the final pass.  May be used by
4008    output templates to customary add branch prediction hints.
4009  */
4010 int
4011 final_forward_branch_p (rtx insn)
4012 {
4013   int insn_id, label_id;
4014 
4015   gcc_assert (uid_shuid);
4016   insn_id = INSN_SHUID (insn);
4017   label_id = INSN_SHUID (JUMP_LABEL (insn));
4018   /* We've hit some insns that does not have id information available.  */
4019   gcc_assert (insn_id && label_id);
4020   return insn_id < label_id;
4021 }
4022 
4023 /* On some machines, a function with no call insns
4024    can run faster if it doesn't create its own register window.
4025    When output, the leaf function should use only the "output"
4026    registers.  Ordinarily, the function would be compiled to use
4027    the "input" registers to find its arguments; it is a candidate
4028    for leaf treatment if it uses only the "input" registers.
4029    Leaf function treatment means renumbering so the function
4030    uses the "output" registers instead.  */
4031 
4032 #ifdef LEAF_REGISTERS
4033 
4034 /* Return 1 if this function uses only the registers that can be
4035    safely renumbered.  */
4036 
4037 int
4038 only_leaf_regs_used (void)
4039 {
4040   int i;
4041   const char *const permitted_reg_in_leaf_functions = LEAF_REGISTERS;
4042 
4043   for (i = 0; i < FIRST_PSEUDO_REGISTER; i++)
4044     if ((df_regs_ever_live_p (i) || global_regs[i])
4045 	&& ! permitted_reg_in_leaf_functions[i])
4046       return 0;
4047 
4048   if (crtl->uses_pic_offset_table
4049       && pic_offset_table_rtx != 0
4050       && REG_P (pic_offset_table_rtx)
4051       && ! permitted_reg_in_leaf_functions[REGNO (pic_offset_table_rtx)])
4052     return 0;
4053 
4054   return 1;
4055 }
4056 
4057 /* Scan all instructions and renumber all registers into those
4058    available in leaf functions.  */
4059 
4060 static void
4061 leaf_renumber_regs (rtx first)
4062 {
4063   rtx insn;
4064 
4065   /* Renumber only the actual patterns.
4066      The reg-notes can contain frame pointer refs,
4067      and renumbering them could crash, and should not be needed.  */
4068   for (insn = first; insn; insn = NEXT_INSN (insn))
4069     if (INSN_P (insn))
4070       leaf_renumber_regs_insn (PATTERN (insn));
4071   for (insn = crtl->epilogue_delay_list;
4072        insn;
4073        insn = XEXP (insn, 1))
4074     if (INSN_P (XEXP (insn, 0)))
4075       leaf_renumber_regs_insn (PATTERN (XEXP (insn, 0)));
4076 }
4077 
4078 /* Scan IN_RTX and its subexpressions, and renumber all regs into those
4079    available in leaf functions.  */
4080 
4081 void
4082 leaf_renumber_regs_insn (rtx in_rtx)
4083 {
4084   int i, j;
4085   const char *format_ptr;
4086 
4087   if (in_rtx == 0)
4088     return;
4089 
4090   /* Renumber all input-registers into output-registers.
4091      renumbered_regs would be 1 for an output-register;
4092      they  */
4093 
4094   if (REG_P (in_rtx))
4095     {
4096       int newreg;
4097 
4098       /* Don't renumber the same reg twice.  */
4099       if (in_rtx->used)
4100 	return;
4101 
4102       newreg = REGNO (in_rtx);
4103       /* Don't try to renumber pseudo regs.  It is possible for a pseudo reg
4104 	 to reach here as part of a REG_NOTE.  */
4105       if (newreg >= FIRST_PSEUDO_REGISTER)
4106 	{
4107 	  in_rtx->used = 1;
4108 	  return;
4109 	}
4110       newreg = LEAF_REG_REMAP (newreg);
4111       gcc_assert (newreg >= 0);
4112       df_set_regs_ever_live (REGNO (in_rtx), false);
4113       df_set_regs_ever_live (newreg, true);
4114       SET_REGNO (in_rtx, newreg);
4115       in_rtx->used = 1;
4116     }
4117 
4118   if (INSN_P (in_rtx))
4119     {
4120       /* Inside a SEQUENCE, we find insns.
4121 	 Renumber just the patterns of these insns,
4122 	 just as we do for the top-level insns.  */
4123       leaf_renumber_regs_insn (PATTERN (in_rtx));
4124       return;
4125     }
4126 
4127   format_ptr = GET_RTX_FORMAT (GET_CODE (in_rtx));
4128 
4129   for (i = 0; i < GET_RTX_LENGTH (GET_CODE (in_rtx)); i++)
4130     switch (*format_ptr++)
4131       {
4132       case 'e':
4133 	leaf_renumber_regs_insn (XEXP (in_rtx, i));
4134 	break;
4135 
4136       case 'E':
4137 	if (NULL != XVEC (in_rtx, i))
4138 	  {
4139 	    for (j = 0; j < XVECLEN (in_rtx, i); j++)
4140 	      leaf_renumber_regs_insn (XVECEXP (in_rtx, i, j));
4141 	  }
4142 	break;
4143 
4144       case 'S':
4145       case 's':
4146       case '0':
4147       case 'i':
4148       case 'w':
4149       case 'n':
4150       case 'u':
4151 	break;
4152 
4153       default:
4154 	gcc_unreachable ();
4155       }
4156 }
4157 #endif
4158 
4159 
4160 /* When -gused is used, emit debug info for only used symbols. But in
4161    addition to the standard intercepted debug_hooks there are some direct
4162    calls into this file, i.e., dbxout_symbol, dbxout_parms, and dbxout_reg_params.
4163    Those routines may also be called from a higher level intercepted routine. So
4164    to prevent recording data for an inner call to one of these for an intercept,
4165    we maintain an intercept nesting counter (debug_nesting). We only save the
4166    intercepted arguments if the nesting is 1.  */
4167 int debug_nesting = 0;
4168 
4169 static tree *symbol_queue;
4170 int symbol_queue_index = 0;
4171 static int symbol_queue_size = 0;
4172 
4173 /* Generate the symbols for any queued up type symbols we encountered
4174    while generating the type info for some originally used symbol.
4175    This might generate additional entries in the queue.  Only when
4176    the nesting depth goes to 0 is this routine called.  */
4177 
4178 void
4179 debug_flush_symbol_queue (void)
4180 {
4181   int i;
4182 
4183   /* Make sure that additionally queued items are not flushed
4184      prematurely.  */
4185 
4186   ++debug_nesting;
4187 
4188   for (i = 0; i < symbol_queue_index; ++i)
4189     {
4190       /* If we pushed queued symbols then such symbols must be
4191          output no matter what anyone else says.  Specifically,
4192          we need to make sure dbxout_symbol() thinks the symbol was
4193          used and also we need to override TYPE_DECL_SUPPRESS_DEBUG
4194          which may be set for outside reasons.  */
4195       int saved_tree_used = TREE_USED (symbol_queue[i]);
4196       int saved_suppress_debug = TYPE_DECL_SUPPRESS_DEBUG (symbol_queue[i]);
4197       TREE_USED (symbol_queue[i]) = 1;
4198       TYPE_DECL_SUPPRESS_DEBUG (symbol_queue[i]) = 0;
4199 
4200 #ifdef DBX_DEBUGGING_INFO
4201       dbxout_symbol (symbol_queue[i], 0);
4202 #endif
4203 
4204       TREE_USED (symbol_queue[i]) = saved_tree_used;
4205       TYPE_DECL_SUPPRESS_DEBUG (symbol_queue[i]) = saved_suppress_debug;
4206     }
4207 
4208   symbol_queue_index = 0;
4209   --debug_nesting;
4210 }
4211 
4212 /* Queue a type symbol needed as part of the definition of a decl
4213    symbol.  These symbols are generated when debug_flush_symbol_queue()
4214    is called.  */
4215 
4216 void
4217 debug_queue_symbol (tree decl)
4218 {
4219   if (symbol_queue_index >= symbol_queue_size)
4220     {
4221       symbol_queue_size += 10;
4222       symbol_queue = XRESIZEVEC (tree, symbol_queue, symbol_queue_size);
4223     }
4224 
4225   symbol_queue[symbol_queue_index++] = decl;
4226 }
4227 
4228 /* Free symbol queue.  */
4229 void
4230 debug_free_queue (void)
4231 {
4232   if (symbol_queue)
4233     {
4234       free (symbol_queue);
4235       symbol_queue = NULL;
4236       symbol_queue_size = 0;
4237     }
4238 }
4239 
4240 /* Turn the RTL into assembly.  */
4241 static unsigned int
4242 rest_of_handle_final (void)
4243 {
4244   rtx x;
4245   const char *fnname;
4246 
4247   /* Get the function's name, as described by its RTL.  This may be
4248      different from the DECL_NAME name used in the source file.  */
4249 
4250   x = DECL_RTL (current_function_decl);
4251   gcc_assert (MEM_P (x));
4252   x = XEXP (x, 0);
4253   gcc_assert (GET_CODE (x) == SYMBOL_REF);
4254   fnname = XSTR (x, 0);
4255 
4256   assemble_start_function (current_function_decl, fnname);
4257   final_start_function (get_insns (), asm_out_file, optimize);
4258   final (get_insns (), asm_out_file, optimize);
4259   final_end_function ();
4260 
4261 #ifdef TARGET_UNWIND_INFO
4262   /* ??? The IA-64 ".handlerdata" directive must be issued before
4263      the ".endp" directive that closes the procedure descriptor.  */
4264   output_function_exception_table (fnname);
4265 #endif
4266 
4267   assemble_end_function (current_function_decl, fnname);
4268 
4269 #ifndef TARGET_UNWIND_INFO
4270   /* Otherwise, it feels unclean to switch sections in the middle.  */
4271   output_function_exception_table (fnname);
4272 #endif
4273 
4274   user_defined_section_attribute = false;
4275 
4276   /* Free up reg info memory.  */
4277   free_reg_info ();
4278 
4279   if (! quiet_flag)
4280     fflush (asm_out_file);
4281 
4282   /* Write DBX symbols if requested.  */
4283 
4284   /* Note that for those inline functions where we don't initially
4285      know for certain that we will be generating an out-of-line copy,
4286      the first invocation of this routine (rest_of_compilation) will
4287      skip over this code by doing a `goto exit_rest_of_compilation;'.
4288      Later on, wrapup_global_declarations will (indirectly) call
4289      rest_of_compilation again for those inline functions that need
4290      to have out-of-line copies generated.  During that call, we
4291      *will* be routed past here.  */
4292 
4293   timevar_push (TV_SYMOUT);
4294   if (!DECL_IGNORED_P (current_function_decl))
4295     debug_hooks->function_decl (current_function_decl);
4296   timevar_pop (TV_SYMOUT);
4297 
4298   /* Release the blocks that are linked to DECL_INITIAL() to free the memory.  */
4299   DECL_INITIAL (current_function_decl) = error_mark_node;
4300 
4301   if (DECL_STATIC_CONSTRUCTOR (current_function_decl)
4302       && targetm.have_ctors_dtors)
4303     targetm.asm_out.constructor (XEXP (DECL_RTL (current_function_decl), 0),
4304 				 decl_init_priority_lookup
4305 				   (current_function_decl));
4306   if (DECL_STATIC_DESTRUCTOR (current_function_decl)
4307       && targetm.have_ctors_dtors)
4308     targetm.asm_out.destructor (XEXP (DECL_RTL (current_function_decl), 0),
4309 				decl_fini_priority_lookup
4310 				  (current_function_decl));
4311   return 0;
4312 }
4313 
4314 struct rtl_opt_pass pass_final =
4315 {
4316  {
4317   RTL_PASS,
4318   "final",                              /* name */
4319   NULL,                                 /* gate */
4320   rest_of_handle_final,                 /* execute */
4321   NULL,                                 /* sub */
4322   NULL,                                 /* next */
4323   0,                                    /* static_pass_number */
4324   TV_FINAL,                             /* tv_id */
4325   0,                                    /* properties_required */
4326   0,                                    /* properties_provided */
4327   0,                                    /* properties_destroyed */
4328   0,                                    /* todo_flags_start */
4329   TODO_ggc_collect                      /* todo_flags_finish */
4330  }
4331 };
4332 
4333 
4334 static unsigned int
4335 rest_of_handle_shorten_branches (void)
4336 {
4337   /* Shorten branches.  */
4338   shorten_branches (get_insns ());
4339   return 0;
4340 }
4341 
4342 struct rtl_opt_pass pass_shorten_branches =
4343 {
4344  {
4345   RTL_PASS,
4346   "shorten",                            /* name */
4347   NULL,                                 /* gate */
4348   rest_of_handle_shorten_branches,      /* execute */
4349   NULL,                                 /* sub */
4350   NULL,                                 /* next */
4351   0,                                    /* static_pass_number */
4352   TV_FINAL,                             /* tv_id */
4353   0,                                    /* properties_required */
4354   0,                                    /* properties_provided */
4355   0,                                    /* properties_destroyed */
4356   0,                                    /* todo_flags_start */
4357   TODO_dump_func                        /* todo_flags_finish */
4358  }
4359 };
4360 
4361 
4362 static unsigned int
4363 rest_of_clean_state (void)
4364 {
4365   rtx insn, next;
4366   FILE *final_output = NULL;
4367   int save_unnumbered = flag_dump_unnumbered;
4368   int save_noaddr = flag_dump_noaddr;
4369 
4370   if (flag_dump_final_insns)
4371     {
4372       final_output = fopen (flag_dump_final_insns, "a");
4373       if (!final_output)
4374 	{
4375 	  error ("could not open final insn dump file %qs: %s",
4376 		 flag_dump_final_insns, strerror (errno));
4377 	  flag_dump_final_insns = NULL;
4378 	}
4379       else
4380 	{
4381 	  const char *aname;
4382 
4383 	  aname = (IDENTIFIER_POINTER
4384 		   (DECL_ASSEMBLER_NAME (current_function_decl)));
4385 	  fprintf (final_output, "\n;; Function (%s) %s\n\n", aname,
4386 	     cfun->function_frequency == FUNCTION_FREQUENCY_HOT
4387 	     ? " (hot)"
4388 	     : cfun->function_frequency == FUNCTION_FREQUENCY_UNLIKELY_EXECUTED
4389 	     ? " (unlikely executed)"
4390 	     : "");
4391 
4392 	  flag_dump_noaddr = flag_dump_unnumbered = 1;
4393 	  if (flag_compare_debug_opt || flag_compare_debug)
4394 	    dump_flags |= TDF_NOUID;
4395 	  final_insns_dump_p = true;
4396 
4397 	  for (insn = get_insns (); insn; insn = NEXT_INSN (insn))
4398 	    if (LABEL_P (insn))
4399 	      INSN_UID (insn) = CODE_LABEL_NUMBER (insn);
4400 	    else
4401 	      INSN_UID (insn) = 0;
4402 	}
4403     }
4404 
4405   /* It is very important to decompose the RTL instruction chain here:
4406      debug information keeps pointing into CODE_LABEL insns inside the function
4407      body.  If these remain pointing to the other insns, we end up preserving
4408      whole RTL chain and attached detailed debug info in memory.  */
4409   for (insn = get_insns (); insn; insn = next)
4410     {
4411       next = NEXT_INSN (insn);
4412       NEXT_INSN (insn) = NULL;
4413       PREV_INSN (insn) = NULL;
4414 
4415       if (final_output
4416 	  && (!NOTE_P (insn) ||
4417 	      (NOTE_KIND (insn) != NOTE_INSN_VAR_LOCATION
4418 	       && NOTE_KIND (insn) != NOTE_INSN_BLOCK_BEG
4419 	       && NOTE_KIND (insn) != NOTE_INSN_BLOCK_END
4420 	       && NOTE_KIND (insn) != NOTE_INSN_CFA_RESTORE_STATE)))
4421 	print_rtl_single (final_output, insn);
4422 
4423     }
4424 
4425   if (final_output)
4426     {
4427       flag_dump_noaddr = save_noaddr;
4428       flag_dump_unnumbered = save_unnumbered;
4429       final_insns_dump_p = false;
4430 
4431       if (fclose (final_output))
4432 	{
4433 	  error ("could not close final insn dump file %qs: %s",
4434 		 flag_dump_final_insns, strerror (errno));
4435 	  flag_dump_final_insns = NULL;
4436 	}
4437     }
4438 
4439   /* In case the function was not output,
4440      don't leave any temporary anonymous types
4441      queued up for sdb output.  */
4442 #ifdef SDB_DEBUGGING_INFO
4443   if (write_symbols == SDB_DEBUG)
4444     sdbout_types (NULL_TREE);
4445 #endif
4446 
4447   flag_rerun_cse_after_global_opts = 0;
4448   reload_completed = 0;
4449   epilogue_completed = 0;
4450 #ifdef STACK_REGS
4451   regstack_completed = 0;
4452 #endif
4453 
4454   /* Clear out the insn_length contents now that they are no
4455      longer valid.  */
4456   init_insn_lengths ();
4457 
4458   /* Show no temporary slots allocated.  */
4459   init_temp_slots ();
4460 
4461   free_bb_for_insn ();
4462 
4463   delete_tree_ssa ();
4464 
4465   if (targetm.binds_local_p (current_function_decl))
4466     {
4467       unsigned int pref = crtl->preferred_stack_boundary;
4468       if (crtl->stack_alignment_needed > crtl->preferred_stack_boundary)
4469         pref = crtl->stack_alignment_needed;
4470       cgraph_rtl_info (current_function_decl)->preferred_incoming_stack_boundary
4471         = pref;
4472     }
4473 
4474   /* Make sure volatile mem refs aren't considered valid operands for
4475      arithmetic insns.  We must call this here if this is a nested inline
4476      function, since the above code leaves us in the init_recog state,
4477      and the function context push/pop code does not save/restore volatile_ok.
4478 
4479      ??? Maybe it isn't necessary for expand_start_function to call this
4480      anymore if we do it here?  */
4481 
4482   init_recog_no_volatile ();
4483 
4484   /* We're done with this function.  Free up memory if we can.  */
4485   free_after_parsing (cfun);
4486   free_after_compilation (cfun);
4487   return 0;
4488 }
4489 
4490 struct rtl_opt_pass pass_clean_state =
4491 {
4492  {
4493   RTL_PASS,
4494   "*clean_state",                       /* name */
4495   NULL,                                 /* gate */
4496   rest_of_clean_state,                  /* execute */
4497   NULL,                                 /* sub */
4498   NULL,                                 /* next */
4499   0,                                    /* static_pass_number */
4500   TV_FINAL,                             /* tv_id */
4501   0,                                    /* properties_required */
4502   0,                                    /* properties_provided */
4503   PROP_rtl,                             /* properties_destroyed */
4504   0,                                    /* todo_flags_start */
4505   0                                     /* todo_flags_finish */
4506  }
4507 };
4508