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