1 /* Definitions for code generation pass of GNU compiler.
2 Copyright (C) 1987, 1991, 1992, 1993, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006, 2007
4 Free Software Foundation, Inc.
6 This file is part of GCC.
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
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
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/>. */
25 /* For inhibit_defer_pop */
27 /* For XEXP, GEN_INT, rtx_code */
29 /* For optimize_size */
31 /* For host_integerp, tree_low_cst, fold_convert, size_binop, ssize_int,
32 TREE_CODE, TYPE_SIZE, int_size_in_bytes, */
34 /* For GET_MODE_BITSIZE, word_mode */
37 /* The default branch cost is 1. */
39 #define BRANCH_COST(speed_p, predictable_p) 1
42 /* This is the 4th arg to `expand_expr'.
43 EXPAND_STACK_PARM means we are possibly expanding a call param onto
45 EXPAND_SUM means it is ok to return a PLUS rtx or MULT rtx.
46 EXPAND_INITIALIZER is similar but also record any labels on forced_labels.
47 EXPAND_CONST_ADDRESS means it is ok to return a MEM whose address
48 is a constant that is not a legitimate address.
49 EXPAND_WRITE means we are only going to write to the resulting rtx.
50 EXPAND_MEMORY means we are interested in a memory result, even if
51 the memory is constant and we could have propagated a constant value. */
52 enum expand_modifier
{EXPAND_NORMAL
= 0, EXPAND_STACK_PARM
, EXPAND_SUM
,
53 EXPAND_CONST_ADDRESS
, EXPAND_INITIALIZER
, EXPAND_WRITE
,
56 /* Prevent the compiler from deferring stack pops. See
57 inhibit_defer_pop for more information. */
58 #define NO_DEFER_POP (inhibit_defer_pop += 1)
60 /* Allow the compiler to defer stack pops. See inhibit_defer_pop for
62 #define OK_DEFER_POP (inhibit_defer_pop -= 1)
64 /* If a memory-to-memory move would take MOVE_RATIO or more simple
65 move-instruction sequences, we will do a movmem or libcall instead. */
68 #if defined (HAVE_movmemqi) || defined (HAVE_movmemhi) || defined (HAVE_movmemsi) || defined (HAVE_movmemdi) || defined (HAVE_movmemti)
69 #define MOVE_RATIO(speed) 2
71 /* If we are optimizing for space (-Os), cut down the default move ratio. */
72 #define MOVE_RATIO(speed) ((speed) ? 15 : 3)
76 /* If a clear memory operation would take CLEAR_RATIO or more simple
77 move-instruction sequences, we will do a setmem or libcall instead. */
80 #if defined (HAVE_setmemqi) || defined (HAVE_setmemhi) || defined (HAVE_setmemsi) || defined (HAVE_setmemdi) || defined (HAVE_setmemti)
81 #define CLEAR_RATIO(speed) 2
83 /* If we are optimizing for space, cut down the default clear ratio. */
84 #define CLEAR_RATIO(speed) ((speed) ? 15 :3)
88 /* If a memory set (to value other than zero) operation would take
89 SET_RATIO or more simple move-instruction sequences, we will do a movmem
90 or libcall instead. */
92 #define SET_RATIO(speed) MOVE_RATIO(speed)
95 enum direction
{none
, upward
, downward
};
97 /* Structure to record the size of a sequence of arguments
98 as the sum of a tree-expression and a constant. This structure is
99 also used to store offsets from the stack, which might be negative,
100 so the variable part must be ssizetype, not sizetype. */
104 HOST_WIDE_INT constant
;
108 /* Package up various arg related fields of struct args for
109 locate_and_pad_parm. */
110 struct locate_and_pad_arg_data
112 /* Size of this argument on the stack, rounded up for any padding it
113 gets. If REG_PARM_STACK_SPACE is defined, then register parms are
114 counted here, otherwise they aren't. */
115 struct args_size size
;
116 /* Offset of this argument from beginning of stack-args. */
117 struct args_size offset
;
118 /* Offset to the start of the stack slot. Different from OFFSET
119 if this arg pads downward. */
120 struct args_size slot_offset
;
121 /* The amount that the stack pointer needs to be adjusted to
122 force alignment for the next argument. */
123 struct args_size alignment_pad
;
124 /* Which way we should pad this arg. */
125 enum direction where_pad
;
126 /* slot_offset is at least this aligned. */
127 unsigned int boundary
;
130 /* Add the value of the tree INC to the `struct args_size' TO. */
132 #define ADD_PARM_SIZE(TO, INC) \
135 if (host_integerp (inc, 0)) \
136 (TO).constant += tree_low_cst (inc, 0); \
137 else if ((TO).var == 0) \
138 (TO).var = fold_convert (ssizetype, inc); \
140 (TO).var = size_binop (PLUS_EXPR, (TO).var, \
141 fold_convert (ssizetype, inc)); \
144 #define SUB_PARM_SIZE(TO, DEC) \
147 if (host_integerp (dec, 0)) \
148 (TO).constant -= tree_low_cst (dec, 0); \
149 else if ((TO).var == 0) \
150 (TO).var = size_binop (MINUS_EXPR, ssize_int (0), \
151 fold_convert (ssizetype, dec)); \
153 (TO).var = size_binop (MINUS_EXPR, (TO).var, \
154 fold_convert (ssizetype, dec)); \
157 /* Convert the implicit sum in a `struct args_size' into a tree
158 of type ssizetype. */
159 #define ARGS_SIZE_TREE(SIZE) \
160 ((SIZE).var == 0 ? ssize_int ((SIZE).constant) \
161 : size_binop (PLUS_EXPR, fold_convert (ssizetype, (SIZE).var), \
162 ssize_int ((SIZE).constant)))
164 /* Convert the implicit sum in a `struct args_size' into an rtx. */
165 #define ARGS_SIZE_RTX(SIZE) \
166 ((SIZE).var == 0 ? GEN_INT ((SIZE).constant) \
167 : expand_normal (ARGS_SIZE_TREE (SIZE)))
169 /* Supply a default definition for FUNCTION_ARG_PADDING:
170 usually pad upward, but pad short args downward on
171 big-endian machines. */
173 #define DEFAULT_FUNCTION_ARG_PADDING(MODE, TYPE) \
174 (! BYTES_BIG_ENDIAN \
176 : (((MODE) == BLKmode \
177 ? ((TYPE) && TREE_CODE (TYPE_SIZE (TYPE)) == INTEGER_CST \
178 && int_size_in_bytes (TYPE) < (PARM_BOUNDARY / BITS_PER_UNIT)) \
179 : GET_MODE_BITSIZE (MODE) < PARM_BOUNDARY) \
180 ? downward : upward))
182 #ifndef FUNCTION_ARG_PADDING
183 #define FUNCTION_ARG_PADDING(MODE, TYPE) \
184 DEFAULT_FUNCTION_ARG_PADDING ((MODE), (TYPE))
187 /* Supply a default definition for FUNCTION_ARG_BOUNDARY. Normally, we let
188 FUNCTION_ARG_PADDING, which also pads the length, handle any needed
191 #ifndef FUNCTION_ARG_BOUNDARY
192 #define FUNCTION_ARG_BOUNDARY(MODE, TYPE) PARM_BOUNDARY
195 /* Supply a default definition of STACK_SAVEAREA_MODE for emit_stack_save.
196 Normally move_insn, so Pmode stack pointer. */
198 #ifndef STACK_SAVEAREA_MODE
199 #define STACK_SAVEAREA_MODE(LEVEL) Pmode
202 /* Supply a default definition of STACK_SIZE_MODE for
203 allocate_dynamic_stack_space. Normally PLUS/MINUS, so word_mode. */
205 #ifndef STACK_SIZE_MODE
206 #define STACK_SIZE_MODE word_mode
209 /* Provide default values for the macros controlling stack checking. */
211 /* The default is neither full builtin stack checking... */
212 #ifndef STACK_CHECK_BUILTIN
213 #define STACK_CHECK_BUILTIN 0
216 /* ...nor static builtin stack checking. */
217 #ifndef STACK_CHECK_STATIC_BUILTIN
218 #define STACK_CHECK_STATIC_BUILTIN 0
221 /* The default interval is one page. */
222 #ifndef STACK_CHECK_PROBE_INTERVAL
223 #define STACK_CHECK_PROBE_INTERVAL 4096
226 /* The default is to do a store into the stack. */
227 #ifndef STACK_CHECK_PROBE_LOAD
228 #define STACK_CHECK_PROBE_LOAD 0
231 /* This is a kludge to try to capture the discrepancy between the old
232 mechanism (generic stack checking) and the new mechanism (static
233 builtin stack checking). STACK_CHECK_PROTECT needs to be bumped
234 for the latter because part of the protection area is effectively
235 included in STACK_CHECK_MAX_FRAME_SIZE for the former. */
236 #ifdef STACK_CHECK_PROTECT
237 #define STACK_OLD_CHECK_PROTECT STACK_CHECK_PROTECT
239 #define STACK_OLD_CHECK_PROTECT \
240 (USING_SJLJ_EXCEPTIONS ? 75 * UNITS_PER_WORD : 8 * 1024)
243 /* Minimum amount of stack required to recover from an anticipated stack
244 overflow detection. The default value conveys an estimate of the amount
245 of stack required to propagate an exception. */
246 #ifndef STACK_CHECK_PROTECT
247 #define STACK_CHECK_PROTECT \
248 (USING_SJLJ_EXCEPTIONS ? 75 * UNITS_PER_WORD : 12 * 1024)
251 /* Make the maximum frame size be the largest we can and still only need
252 one probe per function. */
253 #ifndef STACK_CHECK_MAX_FRAME_SIZE
254 #define STACK_CHECK_MAX_FRAME_SIZE \
255 (STACK_CHECK_PROBE_INTERVAL - UNITS_PER_WORD)
258 /* This is arbitrary, but should be large enough everywhere. */
259 #ifndef STACK_CHECK_FIXED_FRAME_SIZE
260 #define STACK_CHECK_FIXED_FRAME_SIZE (4 * UNITS_PER_WORD)
263 /* Provide a reasonable default for the maximum size of an object to
264 allocate in the fixed frame. We may need to be able to make this
265 controllable by the user at some point. */
266 #ifndef STACK_CHECK_MAX_VAR_SIZE
267 #define STACK_CHECK_MAX_VAR_SIZE (STACK_CHECK_MAX_FRAME_SIZE / 100)
270 /* Functions from optabs.c, commonly used, and without need for the optabs
273 /* Passed to expand_simple_binop and expand_binop to say which options
274 to try to use if the requested operation can't be open-coded on the
275 requisite mode. Either OPTAB_LIB or OPTAB_LIB_WIDEN says try using
276 a library call. Either OPTAB_WIDEN or OPTAB_LIB_WIDEN says try
277 using a wider mode. OPTAB_MUST_WIDEN says try widening and don't
278 try anything else. */
289 /* Generate code for a simple binary or unary operation. "Simple" in
290 this case means "can be unambiguously described by a (mode, code)
291 pair and mapped to a single optab." */
292 extern rtx
expand_simple_binop (enum machine_mode
, enum rtx_code
, rtx
,
293 rtx
, rtx
, int, enum optab_methods
);
294 extern rtx
expand_simple_unop (enum machine_mode
, enum rtx_code
, rtx
, rtx
,
297 /* Report whether the machine description contains an insn which can
298 perform the operation described by CODE and MODE. */
299 extern int have_insn_for (enum rtx_code
, enum machine_mode
);
301 /* Emit code to make a call to a constant function or a library call. */
302 extern void emit_libcall_block (rtx
, rtx
, rtx
, rtx
);
304 /* Create but don't emit one rtl instruction to perform certain operations.
305 Modes must match; operands must meet the operation's predicates.
306 Likewise for subtraction and for just copying. */
307 extern rtx
gen_add2_insn (rtx
, rtx
);
308 extern rtx
gen_add3_insn (rtx
, rtx
, rtx
);
309 extern rtx
gen_sub2_insn (rtx
, rtx
);
310 extern rtx
gen_sub3_insn (rtx
, rtx
, rtx
);
311 extern rtx
gen_move_insn (rtx
, rtx
);
312 extern int have_add2_insn (rtx
, rtx
);
313 extern int have_sub2_insn (rtx
, rtx
);
315 /* Emit a pair of rtl insns to compare two rtx's and to jump
316 to a label if the comparison is true. */
317 extern void emit_cmp_and_jump_insns (rtx
, rtx
, enum rtx_code
, rtx
,
318 enum machine_mode
, int, rtx
);
320 /* Generate code to indirectly jump to a location given in the rtx LOC. */
321 extern void emit_indirect_jump (rtx
);
323 /* Generate a conditional trap instruction. */
324 extern rtx
gen_cond_trap (enum rtx_code
, rtx
, rtx
, rtx
);
326 #include "insn-config.h"
328 #ifdef HAVE_conditional_move
329 /* Emit a conditional move operation. */
330 rtx
emit_conditional_move (rtx
, enum rtx_code
, rtx
, rtx
, enum machine_mode
,
331 rtx
, rtx
, enum machine_mode
, int);
333 /* Return nonzero if the conditional move is supported. */
334 int can_conditionally_move_p (enum machine_mode mode
);
337 rtx
emit_conditional_add (rtx
, enum rtx_code
, rtx
, rtx
, enum machine_mode
,
338 rtx
, rtx
, enum machine_mode
, int);
340 rtx
expand_val_compare_and_swap (rtx
, rtx
, rtx
, rtx
);
341 rtx
expand_bool_compare_and_swap (rtx
, rtx
, rtx
, rtx
);
342 rtx
expand_sync_operation (rtx
, rtx
, enum rtx_code
);
343 rtx
expand_sync_fetch_operation (rtx
, rtx
, enum rtx_code
, bool, rtx
);
344 rtx
expand_sync_lock_test_and_set (rtx
, rtx
, rtx
);
346 /* Functions from expmed.c: */
348 /* Arguments MODE, RTX: return an rtx for the negation of that value.
350 extern rtx
negate_rtx (enum machine_mode
, rtx
);
352 /* Expand a logical AND operation. */
353 extern rtx
expand_and (enum machine_mode
, rtx
, rtx
, rtx
);
355 /* Emit a store-flag operation. */
356 extern rtx
emit_store_flag (rtx
, enum rtx_code
, rtx
, rtx
, enum machine_mode
,
359 /* Like emit_store_flag, but always succeeds. */
360 extern rtx
emit_store_flag_force (rtx
, enum rtx_code
, rtx
, rtx
,
361 enum machine_mode
, int, int);
363 /* Functions from builtins.c: */
364 extern rtx
expand_builtin (tree
, rtx
, rtx
, enum machine_mode
, int);
365 extern tree
std_build_builtin_va_list (void);
366 extern tree
std_fn_abi_va_list (tree
);
367 extern tree
std_canonical_va_list_type (tree
);
369 extern void std_expand_builtin_va_start (tree
, rtx
);
370 extern rtx
default_expand_builtin (tree
, rtx
, rtx
, enum machine_mode
, int);
371 extern void expand_builtin_setjmp_setup (rtx
, rtx
);
372 extern void expand_builtin_setjmp_receiver (rtx
);
373 extern rtx
expand_builtin_saveregs (void);
374 extern void expand_builtin_trap (void);
375 extern rtx
builtin_strncpy_read_str (void *, HOST_WIDE_INT
, enum machine_mode
);
377 /* Functions from expr.c: */
379 /* This is run during target initialization to set up which modes can be
380 used directly in memory and to initialize the block move optab. */
381 extern void init_expr_target (void);
383 /* This is run at the start of compiling a function. */
384 extern void init_expr (void);
386 /* Emit some rtl insns to move data between rtx's, converting machine modes.
387 Both modes must be floating or both fixed. */
388 extern void convert_move (rtx
, rtx
, int);
390 /* Convert an rtx to specified machine mode and return the result. */
391 extern rtx
convert_to_mode (enum machine_mode
, rtx
, int);
393 /* Convert an rtx to MODE from OLDMODE and return the result. */
394 extern rtx
convert_modes (enum machine_mode
, enum machine_mode
, rtx
, int);
396 /* Emit code to move a block Y to a block X. */
398 enum block_op_methods
403 /* Like BLOCK_OP_NORMAL, but the libcall can be tail call optimized. */
407 extern void init_block_move_fn (const char *);
408 extern void init_block_clear_fn (const char *);
410 extern rtx
emit_block_move (rtx
, rtx
, rtx
, enum block_op_methods
);
411 extern rtx
emit_block_move_via_libcall (rtx
, rtx
, rtx
, bool);
412 extern rtx
emit_block_move_hints (rtx
, rtx
, rtx
, enum block_op_methods
,
413 unsigned int, HOST_WIDE_INT
);
415 /* Copy all or part of a value X into registers starting at REGNO.
416 The number of registers to be filled is NREGS. */
417 extern void move_block_to_reg (int, rtx
, int, enum machine_mode
);
419 /* Copy all or part of a BLKmode value X out of registers starting at REGNO.
420 The number of registers to be filled is NREGS. */
421 extern void move_block_from_reg (int, rtx
, int);
423 /* Generate a non-consecutive group of registers represented by a PARALLEL. */
424 extern rtx
gen_group_rtx (rtx
);
426 /* Load a BLKmode value into non-consecutive registers represented by a
428 extern void emit_group_load (rtx
, rtx
, tree
, int);
430 /* Similarly, but load into new temporaries. */
431 extern rtx
emit_group_load_into_temps (rtx
, rtx
, tree
, int);
433 /* Move a non-consecutive group of registers represented by a PARALLEL into
434 a non-consecutive group of registers represented by a PARALLEL. */
435 extern void emit_group_move (rtx
, rtx
);
437 /* Move a group of registers represented by a PARALLEL into pseudos. */
438 extern rtx
emit_group_move_into_temps (rtx
);
440 /* Store a BLKmode value from non-consecutive registers represented by a
442 extern void emit_group_store (rtx
, rtx
, tree
, int);
444 /* Copy BLKmode object from a set of registers. */
445 extern rtx
copy_blkmode_from_reg (rtx
, rtx
, tree
);
447 /* Mark REG as holding a parameter for the next CALL_INSN. */
448 extern void use_reg (rtx
*, rtx
);
450 /* Mark NREGS consecutive regs, starting at REGNO, as holding parameters
451 for the next CALL_INSN. */
452 extern void use_regs (rtx
*, int, int);
454 /* Mark a PARALLEL as holding a parameter for the next CALL_INSN. */
455 extern void use_group_regs (rtx
*, rtx
);
457 /* Write zeros through the storage of OBJECT.
458 If OBJECT has BLKmode, SIZE is its length in bytes. */
459 extern rtx
clear_storage (rtx
, rtx
, enum block_op_methods
);
460 extern rtx
clear_storage_hints (rtx
, rtx
, enum block_op_methods
,
461 unsigned int, HOST_WIDE_INT
);
462 /* The same, but always output an library call. */
463 rtx
set_storage_via_libcall (rtx
, rtx
, rtx
, bool);
465 /* Expand a setmem pattern; return true if successful. */
466 extern bool set_storage_via_setmem (rtx
, rtx
, rtx
, unsigned int,
467 unsigned int, HOST_WIDE_INT
);
469 /* Determine whether the LEN bytes can be moved by using several move
470 instructions. Return nonzero if a call to move_by_pieces should
472 extern int can_move_by_pieces (unsigned HOST_WIDE_INT
, unsigned int);
474 /* Return nonzero if it is desirable to store LEN bytes generated by
475 CONSTFUN with several move instructions by store_by_pieces
476 function. CONSTFUNDATA is a pointer which will be passed as argument
477 in every CONSTFUN call.
478 ALIGN is maximum alignment we can assume.
479 MEMSETP is true if this is a real memset/bzero, not a copy
480 of a const string. */
481 extern int can_store_by_pieces (unsigned HOST_WIDE_INT
,
482 rtx (*) (void *, HOST_WIDE_INT
,
484 void *, unsigned int, bool);
486 /* Generate several move instructions to store LEN bytes generated by
487 CONSTFUN to block TO. (A MEM rtx with BLKmode). CONSTFUNDATA is a
488 pointer which will be passed as argument in every CONSTFUN call.
489 ALIGN is maximum alignment we can assume.
490 MEMSETP is true if this is a real memset/bzero, not a copy.
492 extern rtx
store_by_pieces (rtx
, unsigned HOST_WIDE_INT
,
493 rtx (*) (void *, HOST_WIDE_INT
, enum machine_mode
),
494 void *, unsigned int, bool, int);
496 /* Emit insns to set X from Y. */
497 extern rtx
emit_move_insn (rtx
, rtx
);
499 /* Emit insns to set X from Y, with no frills. */
500 extern rtx
emit_move_insn_1 (rtx
, rtx
);
502 extern rtx
emit_move_complex_push (enum machine_mode
, rtx
, rtx
);
503 extern rtx
emit_move_complex_parts (rtx
, rtx
);
505 /* Push a block of length SIZE (perhaps variable)
506 and return an rtx to address the beginning of the block. */
507 extern rtx
push_block (rtx
, int, int);
509 /* Generate code to push something onto the stack, given its mode and type. */
510 extern void emit_push_insn (rtx
, enum machine_mode
, tree
, rtx
, unsigned int,
511 int, rtx
, int, rtx
, rtx
, int, rtx
);
513 /* Expand an assignment that stores the value of FROM into TO. */
514 extern void expand_assignment (tree
, tree
, bool);
516 /* Generate code for computing expression EXP,
517 and storing the value into TARGET.
518 If SUGGEST_REG is nonzero, copy the value through a register
519 and return that register, if that is possible. */
520 extern rtx
store_expr (tree
, rtx
, int, bool);
522 /* Given an rtx that may include add and multiply operations,
523 generate them as insns and return a pseudo-reg containing the value.
524 Useful after calling expand_expr with 1 as sum_ok. */
525 extern rtx
force_operand (rtx
, rtx
);
527 /* Work horse for expand_expr. */
528 extern rtx
expand_expr_real (tree
, rtx
, enum machine_mode
,
529 enum expand_modifier
, rtx
*);
531 /* Generate code for computing expression EXP.
532 An rtx for the computed value is returned. The value is never null.
533 In the case of a void EXP, const0_rtx is returned. */
535 expand_expr (tree exp
, rtx target
, enum machine_mode mode
,
536 enum expand_modifier modifier
)
538 return expand_expr_real (exp
, target
, mode
, modifier
, NULL
);
542 expand_normal (tree exp
)
544 return expand_expr_real (exp
, NULL_RTX
, VOIDmode
, EXPAND_NORMAL
, NULL
);
547 /* At the start of a function, record that we have no previously-pushed
548 arguments waiting to be popped. */
549 extern void init_pending_stack_adjust (void);
551 /* Discard any pending stack adjustment. */
552 extern void discard_pending_stack_adjust (void);
554 /* When exiting from function, if safe, clear out any pending stack adjust
555 so the adjustment won't get done. */
556 extern void clear_pending_stack_adjust (void);
558 /* Pop any previously-pushed arguments that have not been popped yet. */
559 extern void do_pending_stack_adjust (void);
561 /* Return the tree node and offset if a given argument corresponds to
562 a string constant. */
563 extern tree
string_constant (tree
, tree
*);
565 /* Generate code to evaluate EXP and jump to LABEL if the value is zero. */
566 extern void jumpifnot (tree
, rtx
);
568 /* Generate code to evaluate EXP and jump to LABEL if the value is nonzero. */
569 extern void jumpif (tree
, rtx
);
571 /* Generate code to evaluate EXP and jump to IF_FALSE_LABEL if
572 the result is zero, or IF_TRUE_LABEL if the result is one. */
573 extern void do_jump (tree
, rtx
, rtx
);
575 /* Generate rtl to compare two rtx's, will call emit_cmp_insn. */
576 extern rtx
compare_from_rtx (rtx
, rtx
, enum rtx_code
, int, enum machine_mode
,
578 extern void do_compare_rtx_and_jump (rtx
, rtx
, enum rtx_code
, int,
579 enum machine_mode
, rtx
, rtx
, rtx
);
581 /* Two different ways of generating switch statements. */
582 extern int try_casesi (tree
, tree
, tree
, tree
, rtx
, rtx
, rtx
);
583 extern int try_tablejump (tree
, tree
, tree
, tree
, rtx
, rtx
);
585 /* Smallest number of adjacent cases before we use a jump table.
586 XXX Should be a target hook. */
587 extern unsigned int case_values_threshold (void);
589 /* Functions from alias.c */
593 /* rtl.h and tree.h were included. */
594 /* Return an rtx for the size in bytes of the value of an expr. */
595 extern rtx
expr_size (tree
);
597 /* Return a wide integer for the size in bytes of the value of EXP, or -1
598 if the size can vary or is larger than an integer. */
599 extern HOST_WIDE_INT
int_expr_size (tree
);
601 /* Return an rtx that refers to the value returned by a function
602 in its original home. This becomes invalid if any more code is emitted. */
603 extern rtx
hard_function_value (const_tree
, const_tree
, const_tree
, int);
605 extern rtx
prepare_call_address (rtx
, rtx
, rtx
*, int, int);
607 extern bool shift_return_value (enum machine_mode
, bool, rtx
);
609 extern rtx
expand_call (tree
, rtx
, int);
611 extern void fixup_tail_calls (void);
614 extern rtx
expand_shift (enum tree_code
, enum machine_mode
, rtx
, tree
, rtx
,
616 extern rtx
expand_divmod (int, enum tree_code
, enum machine_mode
, rtx
, rtx
,
620 extern void locate_and_pad_parm (enum machine_mode
, tree
, int, int, tree
,
622 struct locate_and_pad_arg_data
*);
624 /* Return the CODE_LABEL rtx for a LABEL_DECL, creating it if necessary. */
625 extern rtx
label_rtx (tree
);
627 /* As label_rtx, but additionally the label is placed on the forced label
628 list of its containing function (i.e. it is treated as reachable even
629 if how is not obvious). */
630 extern rtx
force_label_rtx (tree
);
632 /* Return an rtx like arg but sans any constant terms.
633 Returns the original rtx if it has no constant terms.
634 The constant terms are added and stored via a second arg. */
635 extern rtx
eliminate_constant_term (rtx
, rtx
*);
637 /* Convert arg to a valid memory address for specified machine mode,
638 by emitting insns to perform arithmetic if nec. */
639 extern rtx
memory_address (enum machine_mode
, rtx
);
641 /* Return a memory reference like MEMREF, but with its mode changed
642 to MODE and its address changed to ADDR.
643 (VOIDmode means don't change the mode.
644 NULL for ADDR means don't change the address.) */
645 extern rtx
change_address (rtx
, enum machine_mode
, rtx
);
647 /* Return a memory reference like MEMREF, but with its mode changed
648 to MODE and its address offset by OFFSET bytes. */
649 #define adjust_address(MEMREF, MODE, OFFSET) \
650 adjust_address_1 (MEMREF, MODE, OFFSET, 1, 1)
652 /* Likewise, but the reference is not required to be valid. */
653 #define adjust_address_nv(MEMREF, MODE, OFFSET) \
654 adjust_address_1 (MEMREF, MODE, OFFSET, 0, 1)
656 /* Return a memory reference like MEMREF, but with its mode changed
657 to MODE and its address changed to ADDR, which is assumed to be
658 increased by OFFSET bytes from MEMREF. */
659 #define adjust_automodify_address(MEMREF, MODE, ADDR, OFFSET) \
660 adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 1)
662 /* Likewise, but the reference is not required to be valid. */
663 #define adjust_automodify_address_nv(MEMREF, MODE, ADDR, OFFSET) \
664 adjust_automodify_address_1 (MEMREF, MODE, ADDR, OFFSET, 0)
666 extern rtx
adjust_address_1 (rtx
, enum machine_mode
, HOST_WIDE_INT
, int, int);
667 extern rtx
adjust_automodify_address_1 (rtx
, enum machine_mode
, rtx
,
670 /* Return a memory reference like MEMREF, but whose address is changed by
671 adding OFFSET, an RTX, to it. POW2 is the highest power of two factor
672 known to be in OFFSET (possibly 1). */
673 extern rtx
offset_address (rtx
, rtx
, unsigned HOST_WIDE_INT
);
675 /* Definitions from emit-rtl.c */
676 #include "emit-rtl.h"
678 /* Return a memory reference like MEMREF, but with its mode widened to
679 MODE and adjusted by OFFSET. */
680 extern rtx
widen_memory_access (rtx
, enum machine_mode
, HOST_WIDE_INT
);
682 /* Return a memory reference like MEMREF, but which is known to have a
684 extern rtx
validize_mem (rtx
);
686 extern rtx
use_anchored_address (rtx
);
688 /* Given REF, a MEM, and T, either the type of X or the expression
689 corresponding to REF, set the memory attributes. OBJECTP is nonzero
690 if we are making a new object of this type. */
691 extern void set_mem_attributes (rtx
, tree
, int);
693 /* Similar, except that BITPOS has not yet been applied to REF, so if
694 we alter MEM_OFFSET according to T then we should subtract BITPOS
695 expecting that it'll be added back in later. */
696 extern void set_mem_attributes_minus_bitpos (rtx
, tree
, int, HOST_WIDE_INT
);
698 /* Return OFFSET if XEXP (MEM, 0) - OFFSET is known to be ALIGN
699 bits aligned for 0 <= OFFSET < ALIGN / BITS_PER_UNIT, or
701 extern int get_mem_align_offset (rtx
, int);
703 /* Assemble the static constant template for function entry trampolines. */
704 extern rtx
assemble_trampoline_template (void);
706 /* Copy given rtx to a new temp reg and return that. */
707 extern rtx
copy_to_reg (rtx
);
709 /* Like copy_to_reg but always make the reg Pmode. */
710 extern rtx
copy_addr_to_reg (rtx
);
712 /* Like copy_to_reg but always make the reg the specified mode MODE. */
713 extern rtx
copy_to_mode_reg (enum machine_mode
, rtx
);
715 /* Copy given rtx to given temp reg and return that. */
716 extern rtx
copy_to_suggested_reg (rtx
, rtx
, enum machine_mode
);
718 /* Copy a value to a register if it isn't already a register.
719 Args are mode (in case value is a constant) and the value. */
720 extern rtx
force_reg (enum machine_mode
, rtx
);
722 /* Return given rtx, copied into a new temp reg if it was in memory. */
723 extern rtx
force_not_mem (rtx
);
725 /* Return mode and signedness to use when object is promoted. */
726 extern enum machine_mode
promote_mode (const_tree
, enum machine_mode
, int *, int);
728 /* Remove some bytes from the stack. An rtx says how many. */
729 extern void adjust_stack (rtx
);
731 /* Add some bytes to the stack. An rtx says how many. */
732 extern void anti_adjust_stack (rtx
);
734 /* This enum is used for the following two functions. */
735 enum save_level
{SAVE_BLOCK
, SAVE_FUNCTION
, SAVE_NONLOCAL
};
737 /* Save the stack pointer at the specified level. */
738 extern void emit_stack_save (enum save_level
, rtx
*, rtx
);
740 /* Restore the stack pointer from a save area of the specified level. */
741 extern void emit_stack_restore (enum save_level
, rtx
, rtx
);
743 /* Invoke emit_stack_save for the nonlocal_goto_save_area. */
744 extern void update_nonlocal_goto_save_area (void);
746 /* Allocate some space on the stack dynamically and return its address. An rtx
747 says how many bytes. */
748 extern rtx
allocate_dynamic_stack_space (rtx
, rtx
, int);
750 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
751 FIRST is a constant and size is a Pmode RTX. These are offsets from the
752 current stack pointer. STACK_GROWS_DOWNWARD says whether to add or
753 subtract from the stack. If SIZE is constant, this is done
754 with a fixed number of probes. Otherwise, we must make a loop. */
755 extern void probe_stack_range (HOST_WIDE_INT
, rtx
);
757 /* Return an rtx that refers to the value returned by a library call
758 in its original home. This becomes invalid if any more code is emitted. */
759 extern rtx
hard_libcall_value (enum machine_mode
);
761 /* Return the mode desired by operand N of a particular bitfield
762 insert/extract insn, or MAX_MACHINE_MODE if no such insn is
765 enum extraction_pattern
{ EP_insv
, EP_extv
, EP_extzv
};
766 extern enum machine_mode
767 mode_for_extraction (enum extraction_pattern
, int);
769 extern void store_bit_field (rtx
, unsigned HOST_WIDE_INT
,
770 unsigned HOST_WIDE_INT
, enum machine_mode
, rtx
);
771 extern rtx
extract_bit_field (rtx
, unsigned HOST_WIDE_INT
,
772 unsigned HOST_WIDE_INT
, int, rtx
,
773 enum machine_mode
, enum machine_mode
);
774 extern rtx
extract_low_bits (enum machine_mode
, enum machine_mode
, rtx
);
775 extern rtx
expand_mult (enum machine_mode
, rtx
, rtx
, rtx
, int);
776 extern rtx
expand_mult_highpart_adjust (enum machine_mode
, rtx
, rtx
, rtx
, rtx
, int);
778 extern rtx
assemble_static_space (unsigned HOST_WIDE_INT
);
779 extern int safe_from_p (const_rtx
, tree
, int);
781 /* Call this once to initialize the contents of the optabs
782 appropriately for the current target machine. */
783 extern void init_optabs (void);
784 extern void init_all_optabs (void);
786 /* Call this to initialize an optab function entry. */
787 extern rtx
init_one_libfunc (const char *);
789 extern int vector_mode_valid_p (enum machine_mode
);
791 #endif /* GCC_EXPR_H */