* gcc_update: Update for configure.in -> configure.ac.
[official-gcc.git] / gcc / explow.c
bloba71027447101c7d6d27436c95d99fad55f91a2e5
1 /* Subroutines for manipulating rtx's in semantically interesting ways.
2 Copyright (C) 1987, 1991, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2006
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 2, or (at your option) any later
11 version.
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.
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING. If not, write to the Free
20 Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
21 02110-1301, USA. */
24 #include "config.h"
25 #include "system.h"
26 #include "coretypes.h"
27 #include "tm.h"
28 #include "toplev.h"
29 #include "rtl.h"
30 #include "tree.h"
31 #include "tm_p.h"
32 #include "flags.h"
33 #include "function.h"
34 #include "expr.h"
35 #include "optabs.h"
36 #include "hard-reg-set.h"
37 #include "insn-config.h"
38 #include "ggc.h"
39 #include "recog.h"
40 #include "langhooks.h"
41 #include "target.h"
42 #include "output.h"
44 static rtx break_out_memory_refs (rtx);
45 static void emit_stack_probe (rtx);
48 /* Truncate and perhaps sign-extend C as appropriate for MODE. */
50 HOST_WIDE_INT
51 trunc_int_for_mode (HOST_WIDE_INT c, enum machine_mode mode)
53 int width = GET_MODE_BITSIZE (mode);
55 /* You want to truncate to a _what_? */
56 gcc_assert (SCALAR_INT_MODE_P (mode));
58 /* Canonicalize BImode to 0 and STORE_FLAG_VALUE. */
59 if (mode == BImode)
60 return c & 1 ? STORE_FLAG_VALUE : 0;
62 /* Sign-extend for the requested mode. */
64 if (width < HOST_BITS_PER_WIDE_INT)
66 HOST_WIDE_INT sign = 1;
67 sign <<= width - 1;
68 c &= (sign << 1) - 1;
69 c ^= sign;
70 c -= sign;
73 return c;
76 /* Return an rtx for the sum of X and the integer C. */
78 rtx
79 plus_constant (rtx x, HOST_WIDE_INT c)
81 RTX_CODE code;
82 rtx y;
83 enum machine_mode mode;
84 rtx tem;
85 int all_constant = 0;
87 if (c == 0)
88 return x;
90 restart:
92 code = GET_CODE (x);
93 mode = GET_MODE (x);
94 y = x;
96 switch (code)
98 case CONST_INT:
99 return GEN_INT (INTVAL (x) + c);
101 case CONST_DOUBLE:
103 unsigned HOST_WIDE_INT l1 = CONST_DOUBLE_LOW (x);
104 HOST_WIDE_INT h1 = CONST_DOUBLE_HIGH (x);
105 unsigned HOST_WIDE_INT l2 = c;
106 HOST_WIDE_INT h2 = c < 0 ? ~0 : 0;
107 unsigned HOST_WIDE_INT lv;
108 HOST_WIDE_INT hv;
110 add_double (l1, h1, l2, h2, &lv, &hv);
112 return immed_double_const (lv, hv, VOIDmode);
115 case MEM:
116 /* If this is a reference to the constant pool, try replacing it with
117 a reference to a new constant. If the resulting address isn't
118 valid, don't return it because we have no way to validize it. */
119 if (GET_CODE (XEXP (x, 0)) == SYMBOL_REF
120 && CONSTANT_POOL_ADDRESS_P (XEXP (x, 0)))
123 = force_const_mem (GET_MODE (x),
124 plus_constant (get_pool_constant (XEXP (x, 0)),
125 c));
126 if (memory_address_p (GET_MODE (tem), XEXP (tem, 0)))
127 return tem;
129 break;
131 case CONST:
132 /* If adding to something entirely constant, set a flag
133 so that we can add a CONST around the result. */
134 x = XEXP (x, 0);
135 all_constant = 1;
136 goto restart;
138 case SYMBOL_REF:
139 case LABEL_REF:
140 all_constant = 1;
141 break;
143 case PLUS:
144 /* The interesting case is adding the integer to a sum.
145 Look for constant term in the sum and combine
146 with C. For an integer constant term, we make a combined
147 integer. For a constant term that is not an explicit integer,
148 we cannot really combine, but group them together anyway.
150 Restart or use a recursive call in case the remaining operand is
151 something that we handle specially, such as a SYMBOL_REF.
153 We may not immediately return from the recursive call here, lest
154 all_constant gets lost. */
156 if (GET_CODE (XEXP (x, 1)) == CONST_INT)
158 c += INTVAL (XEXP (x, 1));
160 if (GET_MODE (x) != VOIDmode)
161 c = trunc_int_for_mode (c, GET_MODE (x));
163 x = XEXP (x, 0);
164 goto restart;
166 else if (CONSTANT_P (XEXP (x, 1)))
168 x = gen_rtx_PLUS (mode, XEXP (x, 0), plus_constant (XEXP (x, 1), c));
169 c = 0;
171 else if (find_constant_term_loc (&y))
173 /* We need to be careful since X may be shared and we can't
174 modify it in place. */
175 rtx copy = copy_rtx (x);
176 rtx *const_loc = find_constant_term_loc (&copy);
178 *const_loc = plus_constant (*const_loc, c);
179 x = copy;
180 c = 0;
182 break;
184 default:
185 break;
188 if (c != 0)
189 x = gen_rtx_PLUS (mode, x, GEN_INT (c));
191 if (GET_CODE (x) == SYMBOL_REF || GET_CODE (x) == LABEL_REF)
192 return x;
193 else if (all_constant)
194 return gen_rtx_CONST (mode, x);
195 else
196 return x;
199 /* If X is a sum, return a new sum like X but lacking any constant terms.
200 Add all the removed constant terms into *CONSTPTR.
201 X itself is not altered. The result != X if and only if
202 it is not isomorphic to X. */
205 eliminate_constant_term (rtx x, rtx *constptr)
207 rtx x0, x1;
208 rtx tem;
210 if (GET_CODE (x) != PLUS)
211 return x;
213 /* First handle constants appearing at this level explicitly. */
214 if (GET_CODE (XEXP (x, 1)) == CONST_INT
215 && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x), *constptr,
216 XEXP (x, 1)))
217 && GET_CODE (tem) == CONST_INT)
219 *constptr = tem;
220 return eliminate_constant_term (XEXP (x, 0), constptr);
223 tem = const0_rtx;
224 x0 = eliminate_constant_term (XEXP (x, 0), &tem);
225 x1 = eliminate_constant_term (XEXP (x, 1), &tem);
226 if ((x1 != XEXP (x, 1) || x0 != XEXP (x, 0))
227 && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x),
228 *constptr, tem))
229 && GET_CODE (tem) == CONST_INT)
231 *constptr = tem;
232 return gen_rtx_PLUS (GET_MODE (x), x0, x1);
235 return x;
238 /* Return an rtx for the size in bytes of the value of EXP. */
241 expr_size (tree exp)
243 tree size;
245 if (TREE_CODE (exp) == WITH_SIZE_EXPR)
246 size = TREE_OPERAND (exp, 1);
247 else
249 size = lang_hooks.expr_size (exp);
250 gcc_assert (size);
251 size = SUBSTITUTE_PLACEHOLDER_IN_EXPR (size, exp);
254 return expand_expr (size, NULL_RTX, TYPE_MODE (sizetype), 0);
257 /* Return a wide integer for the size in bytes of the value of EXP, or -1
258 if the size can vary or is larger than an integer. */
260 HOST_WIDE_INT
261 int_expr_size (tree exp)
263 tree size;
265 if (TREE_CODE (exp) == WITH_SIZE_EXPR)
266 size = TREE_OPERAND (exp, 1);
267 else
269 size = lang_hooks.expr_size (exp);
270 gcc_assert (size);
273 if (size == 0 || !host_integerp (size, 0))
274 return -1;
276 return tree_low_cst (size, 0);
279 /* Return a copy of X in which all memory references
280 and all constants that involve symbol refs
281 have been replaced with new temporary registers.
282 Also emit code to load the memory locations and constants
283 into those registers.
285 If X contains no such constants or memory references,
286 X itself (not a copy) is returned.
288 If a constant is found in the address that is not a legitimate constant
289 in an insn, it is left alone in the hope that it might be valid in the
290 address.
292 X may contain no arithmetic except addition, subtraction and multiplication.
293 Values returned by expand_expr with 1 for sum_ok fit this constraint. */
295 static rtx
296 break_out_memory_refs (rtx x)
298 if (MEM_P (x)
299 || (CONSTANT_P (x) && CONSTANT_ADDRESS_P (x)
300 && GET_MODE (x) != VOIDmode))
301 x = force_reg (GET_MODE (x), x);
302 else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS
303 || GET_CODE (x) == MULT)
305 rtx op0 = break_out_memory_refs (XEXP (x, 0));
306 rtx op1 = break_out_memory_refs (XEXP (x, 1));
308 if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1))
309 x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1);
312 return x;
315 /* Given X, a memory address in ptr_mode, convert it to an address
316 in Pmode, or vice versa (TO_MODE says which way). We take advantage of
317 the fact that pointers are not allowed to overflow by commuting arithmetic
318 operations over conversions so that address arithmetic insns can be
319 used. */
322 convert_memory_address (enum machine_mode to_mode ATTRIBUTE_UNUSED,
323 rtx x)
325 #ifndef POINTERS_EXTEND_UNSIGNED
326 gcc_assert (GET_MODE (x) == to_mode || GET_MODE (x) == VOIDmode);
327 return x;
328 #else /* defined(POINTERS_EXTEND_UNSIGNED) */
329 enum machine_mode from_mode;
330 rtx temp;
331 enum rtx_code code;
333 /* If X already has the right mode, just return it. */
334 if (GET_MODE (x) == to_mode)
335 return x;
337 from_mode = to_mode == ptr_mode ? Pmode : ptr_mode;
339 /* Here we handle some special cases. If none of them apply, fall through
340 to the default case. */
341 switch (GET_CODE (x))
343 case CONST_INT:
344 case CONST_DOUBLE:
345 if (GET_MODE_SIZE (to_mode) < GET_MODE_SIZE (from_mode))
346 code = TRUNCATE;
347 else if (POINTERS_EXTEND_UNSIGNED < 0)
348 break;
349 else if (POINTERS_EXTEND_UNSIGNED > 0)
350 code = ZERO_EXTEND;
351 else
352 code = SIGN_EXTEND;
353 temp = simplify_unary_operation (code, to_mode, x, from_mode);
354 if (temp)
355 return temp;
356 break;
358 case SUBREG:
359 if ((SUBREG_PROMOTED_VAR_P (x) || REG_POINTER (SUBREG_REG (x)))
360 && GET_MODE (SUBREG_REG (x)) == to_mode)
361 return SUBREG_REG (x);
362 break;
364 case LABEL_REF:
365 temp = gen_rtx_LABEL_REF (to_mode, XEXP (x, 0));
366 LABEL_REF_NONLOCAL_P (temp) = LABEL_REF_NONLOCAL_P (x);
367 return temp;
368 break;
370 case SYMBOL_REF:
371 temp = shallow_copy_rtx (x);
372 PUT_MODE (temp, to_mode);
373 return temp;
374 break;
376 case CONST:
377 return gen_rtx_CONST (to_mode,
378 convert_memory_address (to_mode, XEXP (x, 0)));
379 break;
381 case PLUS:
382 case MULT:
383 /* For addition we can safely permute the conversion and addition
384 operation if one operand is a constant and converting the constant
385 does not change it. We can always safely permute them if we are
386 making the address narrower. */
387 if (GET_MODE_SIZE (to_mode) < GET_MODE_SIZE (from_mode)
388 || (GET_CODE (x) == PLUS
389 && GET_CODE (XEXP (x, 1)) == CONST_INT
390 && XEXP (x, 1) == convert_memory_address (to_mode, XEXP (x, 1))))
391 return gen_rtx_fmt_ee (GET_CODE (x), to_mode,
392 convert_memory_address (to_mode, XEXP (x, 0)),
393 XEXP (x, 1));
394 break;
396 default:
397 break;
400 return convert_modes (to_mode, from_mode,
401 x, POINTERS_EXTEND_UNSIGNED);
402 #endif /* defined(POINTERS_EXTEND_UNSIGNED) */
405 /* Return something equivalent to X but valid as a memory address
406 for something of mode MODE. When X is not itself valid, this
407 works by copying X or subexpressions of it into registers. */
410 memory_address (enum machine_mode mode, rtx x)
412 rtx oldx = x;
414 x = convert_memory_address (Pmode, x);
416 /* By passing constant addresses through registers
417 we get a chance to cse them. */
418 if (! cse_not_expected && CONSTANT_P (x) && CONSTANT_ADDRESS_P (x))
419 x = force_reg (Pmode, x);
421 /* We get better cse by rejecting indirect addressing at this stage.
422 Let the combiner create indirect addresses where appropriate.
423 For now, generate the code so that the subexpressions useful to share
424 are visible. But not if cse won't be done! */
425 else
427 if (! cse_not_expected && !REG_P (x))
428 x = break_out_memory_refs (x);
430 /* At this point, any valid address is accepted. */
431 if (memory_address_p (mode, x))
432 goto win;
434 /* If it was valid before but breaking out memory refs invalidated it,
435 use it the old way. */
436 if (memory_address_p (mode, oldx))
437 goto win2;
439 /* Perform machine-dependent transformations on X
440 in certain cases. This is not necessary since the code
441 below can handle all possible cases, but machine-dependent
442 transformations can make better code. */
443 LEGITIMIZE_ADDRESS (x, oldx, mode, win);
445 /* PLUS and MULT can appear in special ways
446 as the result of attempts to make an address usable for indexing.
447 Usually they are dealt with by calling force_operand, below.
448 But a sum containing constant terms is special
449 if removing them makes the sum a valid address:
450 then we generate that address in a register
451 and index off of it. We do this because it often makes
452 shorter code, and because the addresses thus generated
453 in registers often become common subexpressions. */
454 if (GET_CODE (x) == PLUS)
456 rtx constant_term = const0_rtx;
457 rtx y = eliminate_constant_term (x, &constant_term);
458 if (constant_term == const0_rtx
459 || ! memory_address_p (mode, y))
460 x = force_operand (x, NULL_RTX);
461 else
463 y = gen_rtx_PLUS (GET_MODE (x), copy_to_reg (y), constant_term);
464 if (! memory_address_p (mode, y))
465 x = force_operand (x, NULL_RTX);
466 else
467 x = y;
471 else if (GET_CODE (x) == MULT || GET_CODE (x) == MINUS)
472 x = force_operand (x, NULL_RTX);
474 /* If we have a register that's an invalid address,
475 it must be a hard reg of the wrong class. Copy it to a pseudo. */
476 else if (REG_P (x))
477 x = copy_to_reg (x);
479 /* Last resort: copy the value to a register, since
480 the register is a valid address. */
481 else
482 x = force_reg (Pmode, x);
484 goto done;
486 win2:
487 x = oldx;
488 win:
489 if (flag_force_addr && ! cse_not_expected && !REG_P (x))
491 x = force_operand (x, NULL_RTX);
492 x = force_reg (Pmode, x);
496 done:
498 /* If we didn't change the address, we are done. Otherwise, mark
499 a reg as a pointer if we have REG or REG + CONST_INT. */
500 if (oldx == x)
501 return x;
502 else if (REG_P (x))
503 mark_reg_pointer (x, BITS_PER_UNIT);
504 else if (GET_CODE (x) == PLUS
505 && REG_P (XEXP (x, 0))
506 && GET_CODE (XEXP (x, 1)) == CONST_INT)
507 mark_reg_pointer (XEXP (x, 0), BITS_PER_UNIT);
509 /* OLDX may have been the address on a temporary. Update the address
510 to indicate that X is now used. */
511 update_temp_slot_address (oldx, x);
513 return x;
516 /* Like `memory_address' but pretend `flag_force_addr' is 0. */
519 memory_address_noforce (enum machine_mode mode, rtx x)
521 int ambient_force_addr = flag_force_addr;
522 rtx val;
524 flag_force_addr = 0;
525 val = memory_address (mode, x);
526 flag_force_addr = ambient_force_addr;
527 return val;
530 /* Convert a mem ref into one with a valid memory address.
531 Pass through anything else unchanged. */
534 validize_mem (rtx ref)
536 if (!MEM_P (ref))
537 return ref;
538 ref = use_anchored_address (ref);
539 if (! (flag_force_addr && CONSTANT_ADDRESS_P (XEXP (ref, 0)))
540 && memory_address_p (GET_MODE (ref), XEXP (ref, 0)))
541 return ref;
543 /* Don't alter REF itself, since that is probably a stack slot. */
544 return replace_equiv_address (ref, XEXP (ref, 0));
547 /* If X is a memory reference to a member of an object block, try rewriting
548 it to use an anchor instead. Return the new memory reference on success
549 and the old one on failure. */
552 use_anchored_address (rtx x)
554 rtx base;
555 HOST_WIDE_INT offset;
557 if (!flag_section_anchors)
558 return x;
560 if (!MEM_P (x))
561 return x;
563 /* Split the address into a base and offset. */
564 base = XEXP (x, 0);
565 offset = 0;
566 if (GET_CODE (base) == CONST
567 && GET_CODE (XEXP (base, 0)) == PLUS
568 && GET_CODE (XEXP (XEXP (base, 0), 1)) == CONST_INT)
570 offset += INTVAL (XEXP (XEXP (base, 0), 1));
571 base = XEXP (XEXP (base, 0), 0);
574 /* Check whether BASE is suitable for anchors. */
575 if (GET_CODE (base) != SYMBOL_REF
576 || !SYMBOL_REF_HAS_BLOCK_INFO_P (base)
577 || SYMBOL_REF_ANCHOR_P (base)
578 || SYMBOL_REF_BLOCK (base) == NULL
579 || !targetm.use_anchors_for_symbol_p (base))
580 return x;
582 /* Decide where BASE is going to be. */
583 place_block_symbol (base);
585 /* Get the anchor we need to use. */
586 offset += SYMBOL_REF_BLOCK_OFFSET (base);
587 base = get_section_anchor (SYMBOL_REF_BLOCK (base), offset,
588 SYMBOL_REF_TLS_MODEL (base));
590 /* Work out the offset from the anchor. */
591 offset -= SYMBOL_REF_BLOCK_OFFSET (base);
593 /* If we're going to run a CSE pass, force the anchor into a register.
594 We will then be able to reuse registers for several accesses, if the
595 target costs say that that's worthwhile. */
596 if (!cse_not_expected)
597 base = force_reg (GET_MODE (base), base);
599 return replace_equiv_address (x, plus_constant (base, offset));
602 /* Copy the value or contents of X to a new temp reg and return that reg. */
605 copy_to_reg (rtx x)
607 rtx temp = gen_reg_rtx (GET_MODE (x));
609 /* If not an operand, must be an address with PLUS and MULT so
610 do the computation. */
611 if (! general_operand (x, VOIDmode))
612 x = force_operand (x, temp);
614 if (x != temp)
615 emit_move_insn (temp, x);
617 return temp;
620 /* Like copy_to_reg but always give the new register mode Pmode
621 in case X is a constant. */
624 copy_addr_to_reg (rtx x)
626 return copy_to_mode_reg (Pmode, x);
629 /* Like copy_to_reg but always give the new register mode MODE
630 in case X is a constant. */
633 copy_to_mode_reg (enum machine_mode mode, rtx x)
635 rtx temp = gen_reg_rtx (mode);
637 /* If not an operand, must be an address with PLUS and MULT so
638 do the computation. */
639 if (! general_operand (x, VOIDmode))
640 x = force_operand (x, temp);
642 gcc_assert (GET_MODE (x) == mode || GET_MODE (x) == VOIDmode);
643 if (x != temp)
644 emit_move_insn (temp, x);
645 return temp;
648 /* Load X into a register if it is not already one.
649 Use mode MODE for the register.
650 X should be valid for mode MODE, but it may be a constant which
651 is valid for all integer modes; that's why caller must specify MODE.
653 The caller must not alter the value in the register we return,
654 since we mark it as a "constant" register. */
657 force_reg (enum machine_mode mode, rtx x)
659 rtx temp, insn, set;
661 if (REG_P (x))
662 return x;
664 if (general_operand (x, mode))
666 temp = gen_reg_rtx (mode);
667 insn = emit_move_insn (temp, x);
669 else
671 temp = force_operand (x, NULL_RTX);
672 if (REG_P (temp))
673 insn = get_last_insn ();
674 else
676 rtx temp2 = gen_reg_rtx (mode);
677 insn = emit_move_insn (temp2, temp);
678 temp = temp2;
682 /* Let optimizers know that TEMP's value never changes
683 and that X can be substituted for it. Don't get confused
684 if INSN set something else (such as a SUBREG of TEMP). */
685 if (CONSTANT_P (x)
686 && (set = single_set (insn)) != 0
687 && SET_DEST (set) == temp
688 && ! rtx_equal_p (x, SET_SRC (set)))
689 set_unique_reg_note (insn, REG_EQUAL, x);
691 /* Let optimizers know that TEMP is a pointer, and if so, the
692 known alignment of that pointer. */
694 unsigned align = 0;
695 if (GET_CODE (x) == SYMBOL_REF)
697 align = BITS_PER_UNIT;
698 if (SYMBOL_REF_DECL (x) && DECL_P (SYMBOL_REF_DECL (x)))
699 align = DECL_ALIGN (SYMBOL_REF_DECL (x));
701 else if (GET_CODE (x) == LABEL_REF)
702 align = BITS_PER_UNIT;
703 else if (GET_CODE (x) == CONST
704 && GET_CODE (XEXP (x, 0)) == PLUS
705 && GET_CODE (XEXP (XEXP (x, 0), 0)) == SYMBOL_REF
706 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
708 rtx s = XEXP (XEXP (x, 0), 0);
709 rtx c = XEXP (XEXP (x, 0), 1);
710 unsigned sa, ca;
712 sa = BITS_PER_UNIT;
713 if (SYMBOL_REF_DECL (s) && DECL_P (SYMBOL_REF_DECL (s)))
714 sa = DECL_ALIGN (SYMBOL_REF_DECL (s));
716 ca = exact_log2 (INTVAL (c) & -INTVAL (c)) * BITS_PER_UNIT;
718 align = MIN (sa, ca);
720 else if (MEM_P (x) && MEM_POINTER (x))
721 align = MEM_ALIGN (x);
723 if (align)
724 mark_reg_pointer (temp, align);
727 return temp;
730 /* If X is a memory ref, copy its contents to a new temp reg and return
731 that reg. Otherwise, return X. */
734 force_not_mem (rtx x)
736 rtx temp;
738 if (!MEM_P (x) || GET_MODE (x) == BLKmode)
739 return x;
741 temp = gen_reg_rtx (GET_MODE (x));
743 if (MEM_POINTER (x))
744 REG_POINTER (temp) = 1;
746 emit_move_insn (temp, x);
747 return temp;
750 /* Copy X to TARGET (if it's nonzero and a reg)
751 or to a new temp reg and return that reg.
752 MODE is the mode to use for X in case it is a constant. */
755 copy_to_suggested_reg (rtx x, rtx target, enum machine_mode mode)
757 rtx temp;
759 if (target && REG_P (target))
760 temp = target;
761 else
762 temp = gen_reg_rtx (mode);
764 emit_move_insn (temp, x);
765 return temp;
768 /* Return the mode to use to store a scalar of TYPE and MODE.
769 PUNSIGNEDP points to the signedness of the type and may be adjusted
770 to show what signedness to use on extension operations.
772 FOR_CALL is nonzero if this call is promoting args for a call. */
774 #if defined(PROMOTE_MODE) && !defined(PROMOTE_FUNCTION_MODE)
775 #define PROMOTE_FUNCTION_MODE PROMOTE_MODE
776 #endif
778 enum machine_mode
779 promote_mode (tree type, enum machine_mode mode, int *punsignedp,
780 int for_call ATTRIBUTE_UNUSED)
782 enum tree_code code = TREE_CODE (type);
783 int unsignedp = *punsignedp;
785 #ifndef PROMOTE_MODE
786 if (! for_call)
787 return mode;
788 #endif
790 switch (code)
792 #ifdef PROMOTE_FUNCTION_MODE
793 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
794 case REAL_TYPE: case OFFSET_TYPE:
795 #ifdef PROMOTE_MODE
796 if (for_call)
798 #endif
799 PROMOTE_FUNCTION_MODE (mode, unsignedp, type);
800 #ifdef PROMOTE_MODE
802 else
804 PROMOTE_MODE (mode, unsignedp, type);
806 #endif
807 break;
808 #endif
810 #ifdef POINTERS_EXTEND_UNSIGNED
811 case REFERENCE_TYPE:
812 case POINTER_TYPE:
813 mode = Pmode;
814 unsignedp = POINTERS_EXTEND_UNSIGNED;
815 break;
816 #endif
818 default:
819 break;
822 *punsignedp = unsignedp;
823 return mode;
826 /* Adjust the stack pointer by ADJUST (an rtx for a number of bytes).
827 This pops when ADJUST is positive. ADJUST need not be constant. */
829 void
830 adjust_stack (rtx adjust)
832 rtx temp;
834 if (adjust == const0_rtx)
835 return;
837 /* We expect all variable sized adjustments to be multiple of
838 PREFERRED_STACK_BOUNDARY. */
839 if (GET_CODE (adjust) == CONST_INT)
840 stack_pointer_delta -= INTVAL (adjust);
842 temp = expand_binop (Pmode,
843 #ifdef STACK_GROWS_DOWNWARD
844 add_optab,
845 #else
846 sub_optab,
847 #endif
848 stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
849 OPTAB_LIB_WIDEN);
851 if (temp != stack_pointer_rtx)
852 emit_move_insn (stack_pointer_rtx, temp);
855 /* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes).
856 This pushes when ADJUST is positive. ADJUST need not be constant. */
858 void
859 anti_adjust_stack (rtx adjust)
861 rtx temp;
863 if (adjust == const0_rtx)
864 return;
866 /* We expect all variable sized adjustments to be multiple of
867 PREFERRED_STACK_BOUNDARY. */
868 if (GET_CODE (adjust) == CONST_INT)
869 stack_pointer_delta += INTVAL (adjust);
871 temp = expand_binop (Pmode,
872 #ifdef STACK_GROWS_DOWNWARD
873 sub_optab,
874 #else
875 add_optab,
876 #endif
877 stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
878 OPTAB_LIB_WIDEN);
880 if (temp != stack_pointer_rtx)
881 emit_move_insn (stack_pointer_rtx, temp);
884 /* Round the size of a block to be pushed up to the boundary required
885 by this machine. SIZE is the desired size, which need not be constant. */
887 static rtx
888 round_push (rtx size)
890 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
892 if (align == 1)
893 return size;
895 if (GET_CODE (size) == CONST_INT)
897 HOST_WIDE_INT new = (INTVAL (size) + align - 1) / align * align;
899 if (INTVAL (size) != new)
900 size = GEN_INT (new);
902 else
904 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
905 but we know it can't. So add ourselves and then do
906 TRUNC_DIV_EXPR. */
907 size = expand_binop (Pmode, add_optab, size, GEN_INT (align - 1),
908 NULL_RTX, 1, OPTAB_LIB_WIDEN);
909 size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size, GEN_INT (align),
910 NULL_RTX, 1);
911 size = expand_mult (Pmode, size, GEN_INT (align), NULL_RTX, 1);
914 return size;
917 /* Save the stack pointer for the purpose in SAVE_LEVEL. PSAVE is a pointer
918 to a previously-created save area. If no save area has been allocated,
919 this function will allocate one. If a save area is specified, it
920 must be of the proper mode.
922 The insns are emitted after insn AFTER, if nonzero, otherwise the insns
923 are emitted at the current position. */
925 void
926 emit_stack_save (enum save_level save_level, rtx *psave, rtx after)
928 rtx sa = *psave;
929 /* The default is that we use a move insn and save in a Pmode object. */
930 rtx (*fcn) (rtx, rtx) = gen_move_insn;
931 enum machine_mode mode = STACK_SAVEAREA_MODE (save_level);
933 /* See if this machine has anything special to do for this kind of save. */
934 switch (save_level)
936 #ifdef HAVE_save_stack_block
937 case SAVE_BLOCK:
938 if (HAVE_save_stack_block)
939 fcn = gen_save_stack_block;
940 break;
941 #endif
942 #ifdef HAVE_save_stack_function
943 case SAVE_FUNCTION:
944 if (HAVE_save_stack_function)
945 fcn = gen_save_stack_function;
946 break;
947 #endif
948 #ifdef HAVE_save_stack_nonlocal
949 case SAVE_NONLOCAL:
950 if (HAVE_save_stack_nonlocal)
951 fcn = gen_save_stack_nonlocal;
952 break;
953 #endif
954 default:
955 break;
958 /* If there is no save area and we have to allocate one, do so. Otherwise
959 verify the save area is the proper mode. */
961 if (sa == 0)
963 if (mode != VOIDmode)
965 if (save_level == SAVE_NONLOCAL)
966 *psave = sa = assign_stack_local (mode, GET_MODE_SIZE (mode), 0);
967 else
968 *psave = sa = gen_reg_rtx (mode);
972 if (after)
974 rtx seq;
976 start_sequence ();
977 do_pending_stack_adjust ();
978 /* We must validize inside the sequence, to ensure that any instructions
979 created by the validize call also get moved to the right place. */
980 if (sa != 0)
981 sa = validize_mem (sa);
982 emit_insn (fcn (sa, stack_pointer_rtx));
983 seq = get_insns ();
984 end_sequence ();
985 emit_insn_after (seq, after);
987 else
989 do_pending_stack_adjust ();
990 if (sa != 0)
991 sa = validize_mem (sa);
992 emit_insn (fcn (sa, stack_pointer_rtx));
996 /* Restore the stack pointer for the purpose in SAVE_LEVEL. SA is the save
997 area made by emit_stack_save. If it is zero, we have nothing to do.
999 Put any emitted insns after insn AFTER, if nonzero, otherwise at
1000 current position. */
1002 void
1003 emit_stack_restore (enum save_level save_level, rtx sa, rtx after)
1005 /* The default is that we use a move insn. */
1006 rtx (*fcn) (rtx, rtx) = gen_move_insn;
1008 /* See if this machine has anything special to do for this kind of save. */
1009 switch (save_level)
1011 #ifdef HAVE_restore_stack_block
1012 case SAVE_BLOCK:
1013 if (HAVE_restore_stack_block)
1014 fcn = gen_restore_stack_block;
1015 break;
1016 #endif
1017 #ifdef HAVE_restore_stack_function
1018 case SAVE_FUNCTION:
1019 if (HAVE_restore_stack_function)
1020 fcn = gen_restore_stack_function;
1021 break;
1022 #endif
1023 #ifdef HAVE_restore_stack_nonlocal
1024 case SAVE_NONLOCAL:
1025 if (HAVE_restore_stack_nonlocal)
1026 fcn = gen_restore_stack_nonlocal;
1027 break;
1028 #endif
1029 default:
1030 break;
1033 if (sa != 0)
1035 sa = validize_mem (sa);
1036 /* These clobbers prevent the scheduler from moving
1037 references to variable arrays below the code
1038 that deletes (pops) the arrays. */
1039 emit_insn (gen_rtx_CLOBBER (VOIDmode,
1040 gen_rtx_MEM (BLKmode,
1041 gen_rtx_SCRATCH (VOIDmode))));
1042 emit_insn (gen_rtx_CLOBBER (VOIDmode,
1043 gen_rtx_MEM (BLKmode, stack_pointer_rtx)));
1046 discard_pending_stack_adjust ();
1048 if (after)
1050 rtx seq;
1052 start_sequence ();
1053 emit_insn (fcn (stack_pointer_rtx, sa));
1054 seq = get_insns ();
1055 end_sequence ();
1056 emit_insn_after (seq, after);
1058 else
1059 emit_insn (fcn (stack_pointer_rtx, sa));
1062 /* Invoke emit_stack_save on the nonlocal_goto_save_area for the current
1063 function. This function should be called whenever we allocate or
1064 deallocate dynamic stack space. */
1066 void
1067 update_nonlocal_goto_save_area (void)
1069 tree t_save;
1070 rtx r_save;
1072 /* The nonlocal_goto_save_area object is an array of N pointers. The
1073 first one is used for the frame pointer save; the rest are sized by
1074 STACK_SAVEAREA_MODE. Create a reference to array index 1, the first
1075 of the stack save area slots. */
1076 t_save = build4 (ARRAY_REF, ptr_type_node, cfun->nonlocal_goto_save_area,
1077 integer_one_node, NULL_TREE, NULL_TREE);
1078 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
1080 emit_stack_save (SAVE_NONLOCAL, &r_save, NULL_RTX);
1083 /* Return an rtx representing the address of an area of memory dynamically
1084 pushed on the stack. This region of memory is always aligned to
1085 a multiple of BIGGEST_ALIGNMENT.
1087 Any required stack pointer alignment is preserved.
1089 SIZE is an rtx representing the size of the area.
1090 TARGET is a place in which the address can be placed.
1092 KNOWN_ALIGN is the alignment (in bits) that we know SIZE has. */
1095 allocate_dynamic_stack_space (rtx size, rtx target, int known_align)
1097 /* If we're asking for zero bytes, it doesn't matter what we point
1098 to since we can't dereference it. But return a reasonable
1099 address anyway. */
1100 if (size == const0_rtx)
1101 return virtual_stack_dynamic_rtx;
1103 /* Otherwise, show we're calling alloca or equivalent. */
1104 current_function_calls_alloca = 1;
1106 /* Ensure the size is in the proper mode. */
1107 if (GET_MODE (size) != VOIDmode && GET_MODE (size) != Pmode)
1108 size = convert_to_mode (Pmode, size, 1);
1110 /* We can't attempt to minimize alignment necessary, because we don't
1111 know the final value of preferred_stack_boundary yet while executing
1112 this code. */
1113 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
1115 /* We will need to ensure that the address we return is aligned to
1116 BIGGEST_ALIGNMENT. If STACK_DYNAMIC_OFFSET is defined, we don't
1117 always know its final value at this point in the compilation (it
1118 might depend on the size of the outgoing parameter lists, for
1119 example), so we must align the value to be returned in that case.
1120 (Note that STACK_DYNAMIC_OFFSET will have a default nonzero value if
1121 STACK_POINTER_OFFSET or ACCUMULATE_OUTGOING_ARGS are defined).
1122 We must also do an alignment operation on the returned value if
1123 the stack pointer alignment is less strict that BIGGEST_ALIGNMENT.
1125 If we have to align, we must leave space in SIZE for the hole
1126 that might result from the alignment operation. */
1128 #if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET)
1129 #define MUST_ALIGN 1
1130 #else
1131 #define MUST_ALIGN (PREFERRED_STACK_BOUNDARY < BIGGEST_ALIGNMENT)
1132 #endif
1134 if (MUST_ALIGN)
1135 size
1136 = force_operand (plus_constant (size,
1137 BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1),
1138 NULL_RTX);
1140 #ifdef SETJMP_VIA_SAVE_AREA
1141 /* If setjmp restores regs from a save area in the stack frame,
1142 avoid clobbering the reg save area. Note that the offset of
1143 virtual_incoming_args_rtx includes the preallocated stack args space.
1144 It would be no problem to clobber that, but it's on the wrong side
1145 of the old save area.
1147 What used to happen is that, since we did not know for sure
1148 whether setjmp() was invoked until after RTL generation, we
1149 would use reg notes to store the "optimized" size and fix things
1150 up later. These days we know this information before we ever
1151 start building RTL so the reg notes are unnecessary. */
1152 if (!current_function_calls_setjmp)
1154 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
1156 /* ??? Code below assumes that the save area needs maximal
1157 alignment. This constraint may be too strong. */
1158 gcc_assert (PREFERRED_STACK_BOUNDARY == BIGGEST_ALIGNMENT);
1160 if (GET_CODE (size) == CONST_INT)
1162 HOST_WIDE_INT new = INTVAL (size) / align * align;
1164 if (INTVAL (size) != new)
1165 size = GEN_INT (new);
1167 else
1169 /* Since we know overflow is not possible, we avoid using
1170 CEIL_DIV_EXPR and use TRUNC_DIV_EXPR instead. */
1171 size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size,
1172 GEN_INT (align), NULL_RTX, 1);
1173 size = expand_mult (Pmode, size,
1174 GEN_INT (align), NULL_RTX, 1);
1177 else
1179 rtx dynamic_offset
1180 = expand_binop (Pmode, sub_optab, virtual_stack_dynamic_rtx,
1181 stack_pointer_rtx, NULL_RTX, 1, OPTAB_LIB_WIDEN);
1183 size = expand_binop (Pmode, add_optab, size, dynamic_offset,
1184 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1186 #endif /* SETJMP_VIA_SAVE_AREA */
1188 /* Round the size to a multiple of the required stack alignment.
1189 Since the stack if presumed to be rounded before this allocation,
1190 this will maintain the required alignment.
1192 If the stack grows downward, we could save an insn by subtracting
1193 SIZE from the stack pointer and then aligning the stack pointer.
1194 The problem with this is that the stack pointer may be unaligned
1195 between the execution of the subtraction and alignment insns and
1196 some machines do not allow this. Even on those that do, some
1197 signal handlers malfunction if a signal should occur between those
1198 insns. Since this is an extremely rare event, we have no reliable
1199 way of knowing which systems have this problem. So we avoid even
1200 momentarily mis-aligning the stack. */
1202 /* If we added a variable amount to SIZE,
1203 we can no longer assume it is aligned. */
1204 #if !defined (SETJMP_VIA_SAVE_AREA)
1205 if (MUST_ALIGN || known_align % PREFERRED_STACK_BOUNDARY != 0)
1206 #endif
1207 size = round_push (size);
1209 do_pending_stack_adjust ();
1211 /* We ought to be called always on the toplevel and stack ought to be aligned
1212 properly. */
1213 gcc_assert (!(stack_pointer_delta
1214 % (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)));
1216 /* If needed, check that we have the required amount of stack. Take into
1217 account what has already been checked. */
1218 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
1219 probe_stack_range (STACK_CHECK_MAX_FRAME_SIZE + STACK_CHECK_PROTECT, size);
1221 /* Don't use a TARGET that isn't a pseudo or is the wrong mode. */
1222 if (target == 0 || !REG_P (target)
1223 || REGNO (target) < FIRST_PSEUDO_REGISTER
1224 || GET_MODE (target) != Pmode)
1225 target = gen_reg_rtx (Pmode);
1227 mark_reg_pointer (target, known_align);
1229 /* Perform the required allocation from the stack. Some systems do
1230 this differently than simply incrementing/decrementing from the
1231 stack pointer, such as acquiring the space by calling malloc(). */
1232 #ifdef HAVE_allocate_stack
1233 if (HAVE_allocate_stack)
1235 enum machine_mode mode = STACK_SIZE_MODE;
1236 insn_operand_predicate_fn pred;
1238 /* We don't have to check against the predicate for operand 0 since
1239 TARGET is known to be a pseudo of the proper mode, which must
1240 be valid for the operand. For operand 1, convert to the
1241 proper mode and validate. */
1242 if (mode == VOIDmode)
1243 mode = insn_data[(int) CODE_FOR_allocate_stack].operand[1].mode;
1245 pred = insn_data[(int) CODE_FOR_allocate_stack].operand[1].predicate;
1246 if (pred && ! ((*pred) (size, mode)))
1247 size = copy_to_mode_reg (mode, convert_to_mode (mode, size, 1));
1249 emit_insn (gen_allocate_stack (target, size));
1251 else
1252 #endif
1254 #ifndef STACK_GROWS_DOWNWARD
1255 emit_move_insn (target, virtual_stack_dynamic_rtx);
1256 #endif
1258 /* Check stack bounds if necessary. */
1259 if (current_function_limit_stack)
1261 rtx available;
1262 rtx space_available = gen_label_rtx ();
1263 #ifdef STACK_GROWS_DOWNWARD
1264 available = expand_binop (Pmode, sub_optab,
1265 stack_pointer_rtx, stack_limit_rtx,
1266 NULL_RTX, 1, OPTAB_WIDEN);
1267 #else
1268 available = expand_binop (Pmode, sub_optab,
1269 stack_limit_rtx, stack_pointer_rtx,
1270 NULL_RTX, 1, OPTAB_WIDEN);
1271 #endif
1272 emit_cmp_and_jump_insns (available, size, GEU, NULL_RTX, Pmode, 1,
1273 space_available);
1274 #ifdef HAVE_trap
1275 if (HAVE_trap)
1276 emit_insn (gen_trap ());
1277 else
1278 #endif
1279 error ("stack limits not supported on this target");
1280 emit_barrier ();
1281 emit_label (space_available);
1284 anti_adjust_stack (size);
1286 #ifdef STACK_GROWS_DOWNWARD
1287 emit_move_insn (target, virtual_stack_dynamic_rtx);
1288 #endif
1291 if (MUST_ALIGN)
1293 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
1294 but we know it can't. So add ourselves and then do
1295 TRUNC_DIV_EXPR. */
1296 target = expand_binop (Pmode, add_optab, target,
1297 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1),
1298 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1299 target = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, target,
1300 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT),
1301 NULL_RTX, 1);
1302 target = expand_mult (Pmode, target,
1303 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT),
1304 NULL_RTX, 1);
1307 /* Record the new stack level for nonlocal gotos. */
1308 if (cfun->nonlocal_goto_save_area != 0)
1309 update_nonlocal_goto_save_area ();
1311 return target;
1314 /* A front end may want to override GCC's stack checking by providing a
1315 run-time routine to call to check the stack, so provide a mechanism for
1316 calling that routine. */
1318 static GTY(()) rtx stack_check_libfunc;
1320 void
1321 set_stack_check_libfunc (rtx libfunc)
1323 stack_check_libfunc = libfunc;
1326 /* Emit one stack probe at ADDRESS, an address within the stack. */
1328 static void
1329 emit_stack_probe (rtx address)
1331 rtx memref = gen_rtx_MEM (word_mode, address);
1333 MEM_VOLATILE_P (memref) = 1;
1335 if (STACK_CHECK_PROBE_LOAD)
1336 emit_move_insn (gen_reg_rtx (word_mode), memref);
1337 else
1338 emit_move_insn (memref, const0_rtx);
1341 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
1342 FIRST is a constant and size is a Pmode RTX. These are offsets from the
1343 current stack pointer. STACK_GROWS_DOWNWARD says whether to add or
1344 subtract from the stack. If SIZE is constant, this is done
1345 with a fixed number of probes. Otherwise, we must make a loop. */
1347 #ifdef STACK_GROWS_DOWNWARD
1348 #define STACK_GROW_OP MINUS
1349 #else
1350 #define STACK_GROW_OP PLUS
1351 #endif
1353 void
1354 probe_stack_range (HOST_WIDE_INT first, rtx size)
1356 /* First ensure SIZE is Pmode. */
1357 if (GET_MODE (size) != VOIDmode && GET_MODE (size) != Pmode)
1358 size = convert_to_mode (Pmode, size, 1);
1360 /* Next see if the front end has set up a function for us to call to
1361 check the stack. */
1362 if (stack_check_libfunc != 0)
1364 rtx addr = memory_address (QImode,
1365 gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1366 stack_pointer_rtx,
1367 plus_constant (size, first)));
1369 addr = convert_memory_address (ptr_mode, addr);
1370 emit_library_call (stack_check_libfunc, LCT_NORMAL, VOIDmode, 1, addr,
1371 ptr_mode);
1374 /* Next see if we have an insn to check the stack. Use it if so. */
1375 #ifdef HAVE_check_stack
1376 else if (HAVE_check_stack)
1378 insn_operand_predicate_fn pred;
1379 rtx last_addr
1380 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1381 stack_pointer_rtx,
1382 plus_constant (size, first)),
1383 NULL_RTX);
1385 pred = insn_data[(int) CODE_FOR_check_stack].operand[0].predicate;
1386 if (pred && ! ((*pred) (last_addr, Pmode)))
1387 last_addr = copy_to_mode_reg (Pmode, last_addr);
1389 emit_insn (gen_check_stack (last_addr));
1391 #endif
1393 /* If we have to generate explicit probes, see if we have a constant
1394 small number of them to generate. If so, that's the easy case. */
1395 else if (GET_CODE (size) == CONST_INT
1396 && INTVAL (size) < 10 * STACK_CHECK_PROBE_INTERVAL)
1398 HOST_WIDE_INT offset;
1400 /* Start probing at FIRST + N * STACK_CHECK_PROBE_INTERVAL
1401 for values of N from 1 until it exceeds LAST. If only one
1402 probe is needed, this will not generate any code. Then probe
1403 at LAST. */
1404 for (offset = first + STACK_CHECK_PROBE_INTERVAL;
1405 offset < INTVAL (size);
1406 offset = offset + STACK_CHECK_PROBE_INTERVAL)
1407 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1408 stack_pointer_rtx,
1409 GEN_INT (offset)));
1411 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1412 stack_pointer_rtx,
1413 plus_constant (size, first)));
1416 /* In the variable case, do the same as above, but in a loop. We emit loop
1417 notes so that loop optimization can be done. */
1418 else
1420 rtx test_addr
1421 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1422 stack_pointer_rtx,
1423 GEN_INT (first + STACK_CHECK_PROBE_INTERVAL)),
1424 NULL_RTX);
1425 rtx last_addr
1426 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1427 stack_pointer_rtx,
1428 plus_constant (size, first)),
1429 NULL_RTX);
1430 rtx incr = GEN_INT (STACK_CHECK_PROBE_INTERVAL);
1431 rtx loop_lab = gen_label_rtx ();
1432 rtx test_lab = gen_label_rtx ();
1433 rtx end_lab = gen_label_rtx ();
1434 rtx temp;
1436 if (!REG_P (test_addr)
1437 || REGNO (test_addr) < FIRST_PSEUDO_REGISTER)
1438 test_addr = force_reg (Pmode, test_addr);
1440 emit_jump (test_lab);
1442 emit_label (loop_lab);
1443 emit_stack_probe (test_addr);
1445 #ifdef STACK_GROWS_DOWNWARD
1446 #define CMP_OPCODE GTU
1447 temp = expand_binop (Pmode, sub_optab, test_addr, incr, test_addr,
1448 1, OPTAB_WIDEN);
1449 #else
1450 #define CMP_OPCODE LTU
1451 temp = expand_binop (Pmode, add_optab, test_addr, incr, test_addr,
1452 1, OPTAB_WIDEN);
1453 #endif
1455 gcc_assert (temp == test_addr);
1457 emit_label (test_lab);
1458 emit_cmp_and_jump_insns (test_addr, last_addr, CMP_OPCODE,
1459 NULL_RTX, Pmode, 1, loop_lab);
1460 emit_jump (end_lab);
1461 emit_label (end_lab);
1463 emit_stack_probe (last_addr);
1467 /* Return an rtx representing the register or memory location
1468 in which a scalar value of data type VALTYPE
1469 was returned by a function call to function FUNC.
1470 FUNC is a FUNCTION_DECL, FNTYPE a FUNCTION_TYPE node if the precise
1471 function is known, otherwise 0.
1472 OUTGOING is 1 if on a machine with register windows this function
1473 should return the register in which the function will put its result
1474 and 0 otherwise. */
1477 hard_function_value (tree valtype, tree func, tree fntype,
1478 int outgoing ATTRIBUTE_UNUSED)
1480 rtx val;
1482 val = targetm.calls.function_value (valtype, func ? func : fntype, outgoing);
1484 if (REG_P (val)
1485 && GET_MODE (val) == BLKmode)
1487 unsigned HOST_WIDE_INT bytes = int_size_in_bytes (valtype);
1488 enum machine_mode tmpmode;
1490 /* int_size_in_bytes can return -1. We don't need a check here
1491 since the value of bytes will then be large enough that no
1492 mode will match anyway. */
1494 for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
1495 tmpmode != VOIDmode;
1496 tmpmode = GET_MODE_WIDER_MODE (tmpmode))
1498 /* Have we found a large enough mode? */
1499 if (GET_MODE_SIZE (tmpmode) >= bytes)
1500 break;
1503 /* No suitable mode found. */
1504 gcc_assert (tmpmode != VOIDmode);
1506 PUT_MODE (val, tmpmode);
1508 return val;
1511 /* Return an rtx representing the register or memory location
1512 in which a scalar value of mode MODE was returned by a library call. */
1515 hard_libcall_value (enum machine_mode mode)
1517 return LIBCALL_VALUE (mode);
1520 /* Look up the tree code for a given rtx code
1521 to provide the arithmetic operation for REAL_ARITHMETIC.
1522 The function returns an int because the caller may not know
1523 what `enum tree_code' means. */
1526 rtx_to_tree_code (enum rtx_code code)
1528 enum tree_code tcode;
1530 switch (code)
1532 case PLUS:
1533 tcode = PLUS_EXPR;
1534 break;
1535 case MINUS:
1536 tcode = MINUS_EXPR;
1537 break;
1538 case MULT:
1539 tcode = MULT_EXPR;
1540 break;
1541 case DIV:
1542 tcode = RDIV_EXPR;
1543 break;
1544 case SMIN:
1545 tcode = MIN_EXPR;
1546 break;
1547 case SMAX:
1548 tcode = MAX_EXPR;
1549 break;
1550 default:
1551 tcode = LAST_AND_UNUSED_TREE_CODE;
1552 break;
1554 return ((int) tcode);
1557 #include "gt-explow.h"