xref: /netbsd-src/external/gpl3/gcc.old/dist/gcc/expr.h (revision d909946ca08dceb44d7d0f22ec9488679695d976)
1 /* Definitions for code generation pass of GNU compiler.
2    Copyright (C) 1987-2013 Free Software Foundation, Inc.
3 
4 This file is part of GCC.
5 
6 GCC is free software; you can redistribute it and/or modify it under
7 the terms of the GNU General Public License as published by the Free
8 Software Foundation; either version 3, or (at your option) any later
9 version.
10 
11 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12 WARRANTY; without even the implied warranty of MERCHANTABILITY or
13 FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14 for more details.
15 
16 You should have received a copy of the GNU General Public License
17 along with GCC; see the file COPYING3.  If not see
18 <http://www.gnu.org/licenses/>.  */
19 
20 #ifndef GCC_EXPR_H
21 #define GCC_EXPR_H
22 
23 /* For inhibit_defer_pop */
24 #include "function.h"
25 /* For XEXP, GEN_INT, rtx_code */
26 #include "rtl.h"
27 /* For optimize_size */
28 #include "flags.h"
29 /* For host_integerp, tree_low_cst, fold_convert, size_binop, ssize_int,
30    TREE_CODE, TYPE_SIZE, int_size_in_bytes,    */
31 #include "tree.h"
32 /* For GET_MODE_BITSIZE, word_mode */
33 #include "machmode.h"
34 
35 /* This is the 4th arg to `expand_expr'.
36    EXPAND_STACK_PARM means we are possibly expanding a call param onto
37    the stack.
38    EXPAND_SUM means it is ok to return a PLUS rtx or MULT rtx.
39    EXPAND_INITIALIZER is similar but also record any labels on forced_labels.
40    EXPAND_CONST_ADDRESS means it is ok to return a MEM whose address
41     is a constant that is not a legitimate address.
42    EXPAND_WRITE means we are only going to write to the resulting rtx.
43    EXPAND_MEMORY means we are interested in a memory result, even if
44     the memory is constant and we could have propagated a constant value,
45     or the memory is unaligned on a STRICT_ALIGNMENT target.  */
46 enum expand_modifier {EXPAND_NORMAL = 0, EXPAND_STACK_PARM, EXPAND_SUM,
47 		      EXPAND_CONST_ADDRESS, EXPAND_INITIALIZER, EXPAND_WRITE,
48 		      EXPAND_MEMORY};
49 
50 /* Prevent the compiler from deferring stack pops.  See
51    inhibit_defer_pop for more information.  */
52 #define NO_DEFER_POP (inhibit_defer_pop += 1)
53 
54 /* Allow the compiler to defer stack pops.  See inhibit_defer_pop for
55    more information.  */
56 #define OK_DEFER_POP (inhibit_defer_pop -= 1)
57 
58 enum direction {none, upward, downward};
59 
60 /* Structure to record the size of a sequence of arguments
61    as the sum of a tree-expression and a constant.  This structure is
62    also used to store offsets from the stack, which might be negative,
63    so the variable part must be ssizetype, not sizetype.  */
64 
65 struct args_size
66 {
67   HOST_WIDE_INT constant;
68   tree var;
69 };
70 
71 /* Package up various arg related fields of struct args for
72    locate_and_pad_parm.  */
73 struct locate_and_pad_arg_data
74 {
75   /* Size of this argument on the stack, rounded up for any padding it
76      gets.  If REG_PARM_STACK_SPACE is defined, then register parms are
77      counted here, otherwise they aren't.  */
78   struct args_size size;
79   /* Offset of this argument from beginning of stack-args.  */
80   struct args_size offset;
81   /* Offset to the start of the stack slot.  Different from OFFSET
82      if this arg pads downward.  */
83   struct args_size slot_offset;
84   /* The amount that the stack pointer needs to be adjusted to
85      force alignment for the next argument.  */
86   struct args_size alignment_pad;
87   /* Which way we should pad this arg.  */
88   enum direction where_pad;
89   /* slot_offset is at least this aligned.  */
90   unsigned int boundary;
91 };
92 
93 /* Add the value of the tree INC to the `struct args_size' TO.  */
94 
95 #define ADD_PARM_SIZE(TO, INC)					\
96 do {								\
97   tree inc = (INC);						\
98   if (host_integerp (inc, 0))					\
99     (TO).constant += tree_low_cst (inc, 0);			\
100   else if ((TO).var == 0)					\
101     (TO).var = fold_convert (ssizetype, inc);			\
102   else								\
103     (TO).var = size_binop (PLUS_EXPR, (TO).var,			\
104 			   fold_convert (ssizetype, inc));	\
105 } while (0)
106 
107 #define SUB_PARM_SIZE(TO, DEC)					\
108 do {								\
109   tree dec = (DEC);						\
110   if (host_integerp (dec, 0))					\
111     (TO).constant -= tree_low_cst (dec, 0);			\
112   else if ((TO).var == 0)					\
113     (TO).var = size_binop (MINUS_EXPR, ssize_int (0),		\
114 			   fold_convert (ssizetype, dec));	\
115   else								\
116     (TO).var = size_binop (MINUS_EXPR, (TO).var,		\
117 			   fold_convert (ssizetype, dec));	\
118 } while (0)
119 
120 /* Convert the implicit sum in a `struct args_size' into a tree
121    of type ssizetype.  */
122 #define ARGS_SIZE_TREE(SIZE)					\
123 ((SIZE).var == 0 ? ssize_int ((SIZE).constant)			\
124  : size_binop (PLUS_EXPR, fold_convert (ssizetype, (SIZE).var),	\
125 	       ssize_int ((SIZE).constant)))
126 
127 /* Convert the implicit sum in a `struct args_size' into an rtx.  */
128 #define ARGS_SIZE_RTX(SIZE)					\
129 ((SIZE).var == 0 ? GEN_INT ((SIZE).constant)			\
130  : expand_normal (ARGS_SIZE_TREE (SIZE)))
131 
132 
133 /* This structure is used to pass around information about exploded
134    unary, binary and trinary expressions between expand_expr_real_1 and
135    friends.  */
136 typedef struct separate_ops
137 {
138   enum tree_code code;
139   location_t location;
140   tree type;
141   tree op0, op1, op2;
142 } *sepops;
143 
144 /* Functions from optabs.c, commonly used, and without need for the optabs
145    tables:  */
146 
147 /* Passed to expand_simple_binop and expand_binop to say which options
148    to try to use if the requested operation can't be open-coded on the
149    requisite mode.  Either OPTAB_LIB or OPTAB_LIB_WIDEN says try using
150    a library call.  Either OPTAB_WIDEN or OPTAB_LIB_WIDEN says try
151    using a wider mode.  OPTAB_MUST_WIDEN says try widening and don't
152    try anything else.  */
153 
154 enum optab_methods
155 {
156   OPTAB_DIRECT,
157   OPTAB_LIB,
158   OPTAB_WIDEN,
159   OPTAB_LIB_WIDEN,
160   OPTAB_MUST_WIDEN
161 };
162 
163 /* Generate code for a simple binary or unary operation.  "Simple" in
164    this case means "can be unambiguously described by a (mode, code)
165    pair and mapped to a single optab."  */
166 extern rtx expand_simple_binop (enum machine_mode, enum rtx_code, rtx,
167 				rtx, rtx, int, enum optab_methods);
168 extern rtx expand_simple_unop (enum machine_mode, enum rtx_code, rtx, rtx,
169 			       int);
170 
171 /* Report whether the machine description contains an insn which can
172    perform the operation described by CODE and MODE.  */
173 extern int have_insn_for (enum rtx_code, enum machine_mode);
174 
175 /* Emit code to make a call to a constant function or a library call.  */
176 extern void emit_libcall_block (rtx, rtx, rtx, rtx);
177 
178 /* Create but don't emit one rtl instruction to perform certain operations.
179    Modes must match; operands must meet the operation's predicates.
180    Likewise for subtraction and for just copying.  */
181 extern rtx gen_add2_insn (rtx, rtx);
182 extern rtx gen_add3_insn (rtx, rtx, rtx);
183 extern rtx gen_sub2_insn (rtx, rtx);
184 extern rtx gen_sub3_insn (rtx, rtx, rtx);
185 extern rtx gen_move_insn (rtx, rtx);
186 extern int have_add2_insn (rtx, rtx);
187 extern int have_sub2_insn (rtx, rtx);
188 
189 /* Emit a pair of rtl insns to compare two rtx's and to jump
190    to a label if the comparison is true.  */
191 extern void emit_cmp_and_jump_insns (rtx, rtx, enum rtx_code, rtx,
192 				     enum machine_mode, int, rtx, int prob=-1);
193 
194 /* Generate code to indirectly jump to a location given in the rtx LOC.  */
195 extern void emit_indirect_jump (rtx);
196 
197 /* Generate a conditional trap instruction.  */
198 extern rtx gen_cond_trap (enum rtx_code, rtx, rtx, rtx);
199 
200 #include "insn-config.h"
201 
202 #ifdef HAVE_conditional_move
203 /* Emit a conditional move operation.  */
204 rtx emit_conditional_move (rtx, enum rtx_code, rtx, rtx, enum machine_mode,
205 			   rtx, rtx, enum machine_mode, int);
206 
207 /* Return nonzero if the conditional move is supported.  */
208 int can_conditionally_move_p (enum machine_mode mode);
209 
210 #endif
211 rtx emit_conditional_add (rtx, enum rtx_code, rtx, rtx, enum machine_mode,
212 			  rtx, rtx, enum machine_mode, int);
213 
214 rtx expand_sync_operation (rtx, rtx, enum rtx_code);
215 rtx expand_sync_fetch_operation (rtx, rtx, enum rtx_code, bool, rtx);
216 rtx expand_sync_lock_test_and_set (rtx, rtx, rtx);
217 
218 rtx expand_atomic_exchange (rtx, rtx, rtx, enum memmodel);
219 rtx expand_atomic_load (rtx, rtx, enum memmodel);
220 rtx expand_atomic_store (rtx, rtx, enum memmodel, bool);
221 rtx expand_atomic_fetch_op (rtx, rtx, rtx, enum rtx_code, enum memmodel,
222 			      bool);
223 rtx expand_atomic_test_and_set (rtx, rtx, enum memmodel);
224 rtx expand_atomic_clear (rtx, enum memmodel);
225 void expand_atomic_thread_fence (enum memmodel);
226 void expand_atomic_signal_fence (enum memmodel);
227 
228 
229 /* Functions from expmed.c:  */
230 
231 /* Arguments MODE, RTX: return an rtx for the negation of that value.
232    May emit insns.  */
233 extern rtx negate_rtx (enum machine_mode, rtx);
234 
235 /* Expand a logical AND operation.  */
236 extern rtx expand_and (enum machine_mode, rtx, rtx, rtx);
237 
238 /* Emit a store-flag operation.  */
239 extern rtx emit_store_flag (rtx, enum rtx_code, rtx, rtx, enum machine_mode,
240 			    int, int);
241 
242 /* Like emit_store_flag, but always succeeds.  */
243 extern rtx emit_store_flag_force (rtx, enum rtx_code, rtx, rtx,
244 				  enum machine_mode, int, int);
245 
246 /* Choose a minimal N + 1 bit approximation to 1/D that can be used to
247    replace division by D, and put the least significant N bits of the result
248    in *MULTIPLIER_PTR and return the most significant bit.  */
249 extern unsigned HOST_WIDE_INT choose_multiplier (unsigned HOST_WIDE_INT, int,
250 						 int, unsigned HOST_WIDE_INT *,
251 						 int *, int *);
252 
253 /* Functions from builtins.c:  */
254 extern rtx expand_builtin (tree, rtx, rtx, enum machine_mode, int);
255 extern tree std_build_builtin_va_list (void);
256 extern tree std_fn_abi_va_list (tree);
257 extern tree std_canonical_va_list_type (tree);
258 
259 extern void std_expand_builtin_va_start (tree, rtx);
260 extern rtx default_expand_builtin (tree, rtx, rtx, enum machine_mode, int);
261 extern void expand_builtin_setjmp_setup (rtx, rtx);
262 extern void expand_builtin_setjmp_receiver (rtx);
263 extern rtx expand_builtin_saveregs (void);
264 extern void expand_builtin_trap (void);
265 extern rtx builtin_strncpy_read_str (void *, HOST_WIDE_INT, enum machine_mode);
266 
267 /* Functions from expr.c:  */
268 
269 /* This is run during target initialization to set up which modes can be
270    used directly in memory and to initialize the block move optab.  */
271 extern void init_expr_target (void);
272 
273 /* This is run at the start of compiling a function.  */
274 extern void init_expr (void);
275 
276 /* Emit some rtl insns to move data between rtx's, converting machine modes.
277    Both modes must be floating or both fixed.  */
278 extern void convert_move (rtx, rtx, int);
279 
280 /* Convert an rtx to specified machine mode and return the result.  */
281 extern rtx convert_to_mode (enum machine_mode, rtx, int);
282 
283 /* Convert an rtx to MODE from OLDMODE and return the result.  */
284 extern rtx convert_modes (enum machine_mode, enum machine_mode, rtx, int);
285 
286 /* Emit code to move a block Y to a block X.  */
287 
288 enum block_op_methods
289 {
290   BLOCK_OP_NORMAL,
291   BLOCK_OP_NO_LIBCALL,
292   BLOCK_OP_CALL_PARM,
293   /* Like BLOCK_OP_NORMAL, but the libcall can be tail call optimized.  */
294   BLOCK_OP_TAILCALL
295 };
296 
297 extern GTY(()) tree block_clear_fn;
298 extern void init_block_move_fn (const char *);
299 extern void init_block_clear_fn (const char *);
300 
301 extern rtx emit_block_move (rtx, rtx, rtx, enum block_op_methods);
302 extern rtx emit_block_move_via_libcall (rtx, rtx, rtx, bool);
303 extern rtx emit_block_move_hints (rtx, rtx, rtx, enum block_op_methods,
304 			          unsigned int, HOST_WIDE_INT);
305 extern bool emit_storent_insn (rtx to, rtx from);
306 
307 /* Copy all or part of a value X into registers starting at REGNO.
308    The number of registers to be filled is NREGS.  */
309 extern void move_block_to_reg (int, rtx, int, enum machine_mode);
310 
311 /* Copy all or part of a BLKmode value X out of registers starting at REGNO.
312    The number of registers to be filled is NREGS.  */
313 extern void move_block_from_reg (int, rtx, int);
314 
315 /* Generate a non-consecutive group of registers represented by a PARALLEL.  */
316 extern rtx gen_group_rtx (rtx);
317 
318 /* Load a BLKmode value into non-consecutive registers represented by a
319    PARALLEL.  */
320 extern void emit_group_load (rtx, rtx, tree, int);
321 
322 /* Similarly, but load into new temporaries.  */
323 extern rtx emit_group_load_into_temps (rtx, rtx, tree, int);
324 
325 /* Move a non-consecutive group of registers represented by a PARALLEL into
326    a non-consecutive group of registers represented by a PARALLEL.  */
327 extern void emit_group_move (rtx, rtx);
328 
329 /* Move a group of registers represented by a PARALLEL into pseudos.  */
330 extern rtx emit_group_move_into_temps (rtx);
331 
332 /* Store a BLKmode value from non-consecutive registers represented by a
333    PARALLEL.  */
334 extern void emit_group_store (rtx, rtx, tree, int);
335 
336 extern rtx maybe_emit_group_store (rtx, tree);
337 
338 /* Copy BLKmode object from a set of registers.  */
339 extern void copy_blkmode_from_reg (rtx, rtx, tree);
340 
341 /* Mark REG as holding a parameter for the next CALL_INSN.
342    Mode is TYPE_MODE of the non-promoted parameter, or VOIDmode.  */
343 extern void use_reg_mode (rtx *, rtx, enum machine_mode);
344 
345 extern rtx copy_blkmode_to_reg (enum machine_mode, tree);
346 
347 /* Mark REG as holding a parameter for the next CALL_INSN.  */
348 static inline void
349 use_reg (rtx *fusage, rtx reg)
350 {
351   use_reg_mode (fusage, reg, VOIDmode);
352 }
353 
354 /* Mark NREGS consecutive regs, starting at REGNO, as holding parameters
355    for the next CALL_INSN.  */
356 extern void use_regs (rtx *, int, int);
357 
358 /* Mark a PARALLEL as holding a parameter for the next CALL_INSN.  */
359 extern void use_group_regs (rtx *, rtx);
360 
361 /* Write zeros through the storage of OBJECT.
362    If OBJECT has BLKmode, SIZE is its length in bytes.  */
363 extern rtx clear_storage (rtx, rtx, enum block_op_methods);
364 extern rtx clear_storage_hints (rtx, rtx, enum block_op_methods,
365 			        unsigned int, HOST_WIDE_INT);
366 /* The same, but always output an library call.  */
367 rtx set_storage_via_libcall (rtx, rtx, rtx, bool);
368 
369 /* Expand a setmem pattern; return true if successful.  */
370 extern bool set_storage_via_setmem (rtx, rtx, rtx, unsigned int,
371 				    unsigned int, HOST_WIDE_INT);
372 
373 extern unsigned HOST_WIDE_INT move_by_pieces_ninsns (unsigned HOST_WIDE_INT,
374 						     unsigned int,
375 						     unsigned int);
376 
377 /* Return nonzero if it is desirable to store LEN bytes generated by
378    CONSTFUN with several move instructions by store_by_pieces
379    function.  CONSTFUNDATA is a pointer which will be passed as argument
380    in every CONSTFUN call.
381    ALIGN is maximum alignment we can assume.
382    MEMSETP is true if this is a real memset/bzero, not a copy
383    of a const string.  */
384 extern int can_store_by_pieces (unsigned HOST_WIDE_INT,
385 				rtx (*) (void *, HOST_WIDE_INT,
386 					 enum machine_mode),
387 				void *, unsigned int, bool);
388 
389 /* Generate several move instructions to store LEN bytes generated by
390    CONSTFUN to block TO.  (A MEM rtx with BLKmode).  CONSTFUNDATA is a
391    pointer which will be passed as argument in every CONSTFUN call.
392    ALIGN is maximum alignment we can assume.
393    MEMSETP is true if this is a real memset/bzero, not a copy.
394    Returns TO + LEN.  */
395 extern rtx store_by_pieces (rtx, unsigned HOST_WIDE_INT,
396 			    rtx (*) (void *, HOST_WIDE_INT, enum machine_mode),
397 			    void *, unsigned int, bool, int);
398 
399 /* Emit insns to set X from Y.  */
400 extern rtx emit_move_insn (rtx, rtx);
401 
402 /* Emit insns to set X from Y, with no frills.  */
403 extern rtx emit_move_insn_1 (rtx, rtx);
404 
405 extern rtx emit_move_complex_push (enum machine_mode, rtx, rtx);
406 extern rtx emit_move_complex_parts (rtx, rtx);
407 
408 /* Push a block of length SIZE (perhaps variable)
409    and return an rtx to address the beginning of the block.  */
410 extern rtx push_block (rtx, int, int);
411 
412 /* Generate code to push something onto the stack, given its mode and type.  */
413 extern void emit_push_insn (rtx, enum machine_mode, tree, rtx, unsigned int,
414 			    int, rtx, int, rtx, rtx, int, rtx);
415 
416 /* Expand an assignment that stores the value of FROM into TO.  */
417 extern void expand_assignment (tree, tree, bool);
418 
419 /* Generate code for computing expression EXP,
420    and storing the value into TARGET.
421    If SUGGEST_REG is nonzero, copy the value through a register
422    and return that register, if that is possible.  */
423 extern rtx store_expr (tree, rtx, int, bool);
424 
425 /* Given an rtx that may include add and multiply operations,
426    generate them as insns and return a pseudo-reg containing the value.
427    Useful after calling expand_expr with 1 as sum_ok.  */
428 extern rtx force_operand (rtx, rtx);
429 
430 /* Work horses for expand_expr.  */
431 extern rtx expand_expr_real (tree, rtx, enum machine_mode,
432 			     enum expand_modifier, rtx *, bool);
433 extern rtx expand_expr_real_1 (tree, rtx, enum machine_mode,
434 			       enum expand_modifier, rtx *, bool);
435 extern rtx expand_expr_real_2 (sepops, rtx, enum machine_mode,
436 			       enum expand_modifier);
437 
438 /* Generate code for computing expression EXP.
439    An rtx for the computed value is returned.  The value is never null.
440    In the case of a void EXP, const0_rtx is returned.  */
441 static inline rtx
442 expand_expr (tree exp, rtx target, enum machine_mode mode,
443 	     enum expand_modifier modifier)
444 {
445   return expand_expr_real (exp, target, mode, modifier, NULL, false);
446 }
447 
448 static inline rtx
449 expand_normal (tree exp)
450 {
451   return expand_expr_real (exp, NULL_RTX, VOIDmode, EXPAND_NORMAL, NULL, false);
452 }
453 
454 /* At the start of a function, record that we have no previously-pushed
455    arguments waiting to be popped.  */
456 extern void init_pending_stack_adjust (void);
457 
458 /* Discard any pending stack adjustment.  */
459 extern void discard_pending_stack_adjust (void);
460 
461 /* When exiting from function, if safe, clear out any pending stack adjust
462    so the adjustment won't get done.  */
463 extern void clear_pending_stack_adjust (void);
464 
465 /* Pop any previously-pushed arguments that have not been popped yet.  */
466 extern void do_pending_stack_adjust (void);
467 
468 /* Return the tree node and offset if a given argument corresponds to
469    a string constant.  */
470 extern tree string_constant (tree, tree *);
471 
472 /* Generate code to evaluate EXP and jump to LABEL if the value is zero.  */
473 extern void jumpifnot (tree, rtx, int);
474 extern void jumpifnot_1 (enum tree_code, tree, tree, rtx, int);
475 
476 /* Generate code to evaluate EXP and jump to LABEL if the value is nonzero.  */
477 extern void jumpif (tree, rtx, int);
478 extern void jumpif_1 (enum tree_code, tree, tree, rtx, int);
479 
480 /* Generate code to evaluate EXP and jump to IF_FALSE_LABEL if
481    the result is zero, or IF_TRUE_LABEL if the result is one.  */
482 extern void do_jump (tree, rtx, rtx, int);
483 extern void do_jump_1 (enum tree_code, tree, tree, rtx, rtx, int);
484 
485 extern void do_compare_rtx_and_jump (rtx, rtx, enum rtx_code, int,
486 				     enum machine_mode, rtx, rtx, rtx, int);
487 
488 /* Two different ways of generating switch statements.  */
489 extern int try_casesi (tree, tree, tree, tree, rtx, rtx, rtx, int);
490 extern int try_tablejump (tree, tree, tree, tree, rtx, rtx, int);
491 
492 /* Functions from alias.c */
493 #include "alias.h"
494 
495 
496 /* rtl.h and tree.h were included.  */
497 /* Return an rtx for the size in bytes of the value of an expr.  */
498 extern rtx expr_size (tree);
499 
500 /* Return a wide integer for the size in bytes of the value of EXP, or -1
501    if the size can vary or is larger than an integer.  */
502 extern HOST_WIDE_INT int_expr_size (tree);
503 
504 /* Return an rtx that refers to the value returned by a function
505    in its original home.  This becomes invalid if any more code is emitted.  */
506 extern rtx hard_function_value (const_tree, const_tree, const_tree, int);
507 
508 extern rtx prepare_call_address (tree, rtx, rtx, rtx *, int, int);
509 
510 extern bool shift_return_value (enum machine_mode, bool, rtx);
511 
512 extern rtx expand_call (tree, rtx, int);
513 
514 extern void fixup_tail_calls (void);
515 
516 #ifdef TREE_CODE
517 extern rtx expand_variable_shift (enum tree_code, enum machine_mode,
518 				  rtx, tree, rtx, int);
519 extern rtx expand_shift (enum tree_code, enum machine_mode, rtx, int, rtx,
520 			     int);
521 extern rtx expand_divmod (int, enum tree_code, enum machine_mode, rtx, rtx,
522 			  rtx, int);
523 #endif
524 
525 extern void locate_and_pad_parm (enum machine_mode, tree, int, int, int,
526 				 tree, struct args_size *,
527 				 struct locate_and_pad_arg_data *);
528 
529 /* Return the CODE_LABEL rtx for a LABEL_DECL, creating it if necessary.  */
530 extern rtx label_rtx (tree);
531 
532 /* As label_rtx, but additionally the label is placed on the forced label
533    list of its containing function (i.e. it is treated as reachable even
534    if how is not obvious).  */
535 extern rtx force_label_rtx (tree);
536 
537 /* Return an rtx like arg but sans any constant terms.
538    Returns the original rtx if it has no constant terms.
539    The constant terms are added and stored via a second arg.  */
540 extern rtx eliminate_constant_term (rtx, rtx *);
541 
542 /* Convert arg to a valid memory address for specified machine mode that points
543    to a specific named address space, by emitting insns to perform arithmetic
544    if necessary.  */
545 extern rtx memory_address_addr_space (enum machine_mode, rtx, addr_space_t);
546 
547 /* Like memory_address_addr_space, except assume the memory address points to
548    the generic named address space.  */
549 #define memory_address(MODE,RTX) \
550 	memory_address_addr_space ((MODE), (RTX), ADDR_SPACE_GENERIC)
551 
552 /* Return a memory reference like MEMREF, but with its mode changed
553    to MODE and its address changed to ADDR.
554    (VOIDmode means don't change the mode.
555    NULL for ADDR means don't change the address.)  */
556 extern rtx change_address (rtx, enum machine_mode, rtx);
557 
558 /* Return a memory reference like MEMREF, but with its mode changed
559    to MODE and its address offset by OFFSET bytes.  */
560 #define adjust_address(MEMREF, MODE, OFFSET) \
561   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 0, 0)
562 
563 /* Likewise, but the reference is not required to be valid.  */
564 #define adjust_address_nv(MEMREF, MODE, OFFSET) \
565   adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 0, 0)
566 
567 /* Return a memory reference like MEMREF, but with its mode changed
568    to MODE and its address offset by OFFSET bytes.  Assume that it's
569    for a bitfield and conservatively drop the underlying object if we
570    cannot be sure to stay within its bounds.  */
571 #define adjust_bitfield_address(MEMREF, MODE, OFFSET) \
572   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, 0)
573 
574 /* As for adjust_bitfield_address, but specify that the width of
575    BLKmode accesses is SIZE bytes.  */
576 #define adjust_bitfield_address_size(MEMREF, MODE, OFFSET, SIZE) \
577   adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1, 1, SIZE)
578 
579 /* Likewise, but the reference is not required to be valid.  */
580 #define adjust_bitfield_address_nv(MEMREF, MODE, OFFSET) \
581   adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1, 1, 0)
582 
583 /* Return a memory reference like MEMREF, but with its mode changed
584    to MODE and its address changed to ADDR, which is assumed to be
585    increased by OFFSET bytes from MEMREF.  */
586 #define adjust_automodify_address(MEMREF, MODE, ADDR, OFFSET) \
587   adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 1)
588 
589 /* Likewise, but the reference is not required to be valid.  */
590 #define adjust_automodify_address_nv(MEMREF, MODE, ADDR, OFFSET) \
591   adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 0)
592 
593 extern rtx adjust_address_1 (rtx, enum machine_mode, HOST_WIDE_INT, int, int,
594 			     int, HOST_WIDE_INT);
595 extern rtx adjust_automodify_address_1 (rtx, enum machine_mode, rtx,
596 					HOST_WIDE_INT, int);
597 
598 /* Return a memory reference like MEMREF, but whose address is changed by
599    adding OFFSET, an RTX, to it.  POW2 is the highest power of two factor
600    known to be in OFFSET (possibly 1).  */
601 extern rtx offset_address (rtx, rtx, unsigned HOST_WIDE_INT);
602 
603 /* Definitions from emit-rtl.c */
604 #include "emit-rtl.h"
605 
606 /* Return a memory reference like MEMREF, but with its mode widened to
607    MODE and adjusted by OFFSET.  */
608 extern rtx widen_memory_access (rtx, enum machine_mode, HOST_WIDE_INT);
609 
610 /* Return a memory reference like MEMREF, but which is known to have a
611    valid address.  */
612 extern rtx validize_mem (rtx);
613 
614 extern rtx use_anchored_address (rtx);
615 
616 /* Given REF, a MEM, and T, either the type of X or the expression
617    corresponding to REF, set the memory attributes.  OBJECTP is nonzero
618    if we are making a new object of this type.  */
619 extern void set_mem_attributes (rtx, tree, int);
620 
621 /* Similar, except that BITPOS has not yet been applied to REF, so if
622    we alter MEM_OFFSET according to T then we should subtract BITPOS
623    expecting that it'll be added back in later.  */
624 extern void set_mem_attributes_minus_bitpos (rtx, tree, int, HOST_WIDE_INT);
625 
626 /* Return OFFSET if XEXP (MEM, 0) - OFFSET is known to be ALIGN
627    bits aligned for 0 <= OFFSET < ALIGN / BITS_PER_UNIT, or
628    -1 if not known.  */
629 extern int get_mem_align_offset (rtx, unsigned int);
630 
631 /* Assemble the static constant template for function entry trampolines.  */
632 extern rtx assemble_trampoline_template (void);
633 
634 /* Copy given rtx to a new temp reg and return that.  */
635 extern rtx copy_to_reg (rtx);
636 
637 /* Like copy_to_reg but always make the reg Pmode.  */
638 extern rtx copy_addr_to_reg (rtx);
639 
640 /* Like copy_to_reg but always make the reg the specified mode MODE.  */
641 extern rtx copy_to_mode_reg (enum machine_mode, rtx);
642 
643 /* Copy given rtx to given temp reg and return that.  */
644 extern rtx copy_to_suggested_reg (rtx, rtx, enum machine_mode);
645 
646 /* Copy a value to a register if it isn't already a register.
647    Args are mode (in case value is a constant) and the value.  */
648 extern rtx force_reg (enum machine_mode, rtx);
649 
650 /* Return given rtx, copied into a new temp reg if it was in memory.  */
651 extern rtx force_not_mem (rtx);
652 
653 /* Return mode and signedness to use when an argument or result in the
654    given mode is promoted.  */
655 extern enum machine_mode promote_function_mode (const_tree, enum machine_mode, int *,
656 					        const_tree, int);
657 
658 /* Return mode and signedness to use when an object in the given mode
659    is promoted.  */
660 extern enum machine_mode promote_mode (const_tree, enum machine_mode, int *);
661 
662 /* Return mode and signedness to use when object is promoted.  */
663 enum machine_mode promote_decl_mode (const_tree, int *);
664 
665 /* Remove some bytes from the stack.  An rtx says how many.  */
666 extern void adjust_stack (rtx);
667 
668 /* Add some bytes to the stack.  An rtx says how many.  */
669 extern void anti_adjust_stack (rtx);
670 
671 /* Add some bytes to the stack while probing it.  An rtx says how many. */
672 extern void anti_adjust_stack_and_probe (rtx, bool);
673 
674 /* This enum is used for the following two functions.  */
675 enum save_level {SAVE_BLOCK, SAVE_FUNCTION, SAVE_NONLOCAL};
676 
677 /* Save the stack pointer at the specified level.  */
678 extern void emit_stack_save (enum save_level, rtx *);
679 
680 /* Restore the stack pointer from a save area of the specified level.  */
681 extern void emit_stack_restore (enum save_level, rtx);
682 
683 /* Invoke emit_stack_save for the nonlocal_goto_save_area.  */
684 extern void update_nonlocal_goto_save_area (void);
685 
686 /* Allocate some space on the stack dynamically and return its address.  */
687 extern rtx allocate_dynamic_stack_space (rtx, unsigned, unsigned, bool);
688 
689 /* Emit one stack probe at ADDRESS, an address within the stack.  */
690 extern void emit_stack_probe (rtx);
691 
692 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
693    FIRST is a constant and size is a Pmode RTX.  These are offsets from
694    the current stack pointer.  STACK_GROWS_DOWNWARD says whether to add
695    or subtract them from the stack pointer.  */
696 extern void probe_stack_range (HOST_WIDE_INT, rtx);
697 
698 /* Return an rtx that refers to the value returned by a library call
699    in its original home.  This becomes invalid if any more code is emitted.  */
700 extern rtx hard_libcall_value (enum machine_mode, rtx);
701 
702 extern void store_bit_field (rtx, unsigned HOST_WIDE_INT,
703 			     unsigned HOST_WIDE_INT,
704 			     unsigned HOST_WIDE_INT,
705 			     unsigned HOST_WIDE_INT,
706 			     enum machine_mode, rtx);
707 extern rtx extract_bit_field (rtx, unsigned HOST_WIDE_INT,
708 			      unsigned HOST_WIDE_INT, int, bool, rtx,
709 			      enum machine_mode, enum machine_mode);
710 extern rtx extract_low_bits (enum machine_mode, enum machine_mode, rtx);
711 extern rtx expand_mult (enum machine_mode, rtx, rtx, rtx, int);
712 extern rtx expand_mult_highpart_adjust (enum machine_mode, rtx, rtx, rtx, rtx, int);
713 
714 extern rtx assemble_static_space (unsigned HOST_WIDE_INT);
715 extern int safe_from_p (const_rtx, tree, int);
716 extern bool split_comparison (enum rtx_code, enum machine_mode,
717 			      enum rtx_code *, enum rtx_code *);
718 
719 /* Call this once to initialize the contents of the optabs
720    appropriately for the current target machine.  */
721 extern void init_optabs (void);
722 extern void init_all_optabs (struct target_optabs *);
723 
724 /* Call this to initialize an optab function entry.  */
725 extern rtx init_one_libfunc (const char *);
726 extern rtx set_user_assembler_libfunc (const char *, const char *);
727 
728 /* Build a decl for a libfunc named NAME. */
729 extern tree build_libfunc_function (const char *);
730 
731 /* Get the personality libfunc for a function decl.  */
732 rtx get_personality_function (tree);
733 
734 
735 /* In stmt.c */
736 
737 /* Expand a GIMPLE_SWITCH statement.  */
738 extern void expand_case (gimple);
739 
740 /* Like expand_case but special-case for SJLJ exception dispatching.  */
741 extern void expand_sjlj_dispatch_table (rtx, vec<tree> );
742 
743 #endif /* GCC_EXPR_H */
744