PR target/35485
[official-gcc.git] / gcc / explow.c
blob498d40e284e0e394701883cf0ffdfaf29d43d6bb
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, 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
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 COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
23 #include "config.h"
24 #include "system.h"
25 #include "coretypes.h"
26 #include "tm.h"
27 #include "toplev.h"
28 #include "rtl.h"
29 #include "tree.h"
30 #include "tm_p.h"
31 #include "flags.h"
32 #include "except.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), EXPAND_NORMAL);
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 = simplify_gen_binary (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 or if one operand is a constant and we are
386 using a ptr_extend instruction (POINTERS_EXTEND_UNSIGNED < 0).
387 We can always safely permute them if we are making the address
388 narrower. */
389 if (GET_MODE_SIZE (to_mode) < GET_MODE_SIZE (from_mode)
390 || (GET_CODE (x) == PLUS
391 && GET_CODE (XEXP (x, 1)) == CONST_INT
392 && (XEXP (x, 1) == convert_memory_address (to_mode, XEXP (x, 1))
393 || POINTERS_EXTEND_UNSIGNED < 0)))
394 return gen_rtx_fmt_ee (GET_CODE (x), to_mode,
395 convert_memory_address (to_mode, XEXP (x, 0)),
396 XEXP (x, 1));
397 break;
399 default:
400 break;
403 return convert_modes (to_mode, from_mode,
404 x, POINTERS_EXTEND_UNSIGNED);
405 #endif /* defined(POINTERS_EXTEND_UNSIGNED) */
408 /* Return something equivalent to X but valid as a memory address
409 for something of mode MODE. When X is not itself valid, this
410 works by copying X or subexpressions of it into registers. */
413 memory_address (enum machine_mode mode, rtx x)
415 rtx oldx = x;
417 x = convert_memory_address (Pmode, x);
419 /* By passing constant addresses through registers
420 we get a chance to cse them. */
421 if (! cse_not_expected && CONSTANT_P (x) && CONSTANT_ADDRESS_P (x))
422 x = force_reg (Pmode, x);
424 /* We get better cse by rejecting indirect addressing at this stage.
425 Let the combiner create indirect addresses where appropriate.
426 For now, generate the code so that the subexpressions useful to share
427 are visible. But not if cse won't be done! */
428 else
430 if (! cse_not_expected && !REG_P (x))
431 x = break_out_memory_refs (x);
433 /* At this point, any valid address is accepted. */
434 if (memory_address_p (mode, x))
435 goto done;
437 /* If it was valid before but breaking out memory refs invalidated it,
438 use it the old way. */
439 if (memory_address_p (mode, oldx))
441 x = oldx;
442 goto done;
445 /* Perform machine-dependent transformations on X
446 in certain cases. This is not necessary since the code
447 below can handle all possible cases, but machine-dependent
448 transformations can make better code. */
449 LEGITIMIZE_ADDRESS (x, oldx, mode, done);
451 /* PLUS and MULT can appear in special ways
452 as the result of attempts to make an address usable for indexing.
453 Usually they are dealt with by calling force_operand, below.
454 But a sum containing constant terms is special
455 if removing them makes the sum a valid address:
456 then we generate that address in a register
457 and index off of it. We do this because it often makes
458 shorter code, and because the addresses thus generated
459 in registers often become common subexpressions. */
460 if (GET_CODE (x) == PLUS)
462 rtx constant_term = const0_rtx;
463 rtx y = eliminate_constant_term (x, &constant_term);
464 if (constant_term == const0_rtx
465 || ! memory_address_p (mode, y))
466 x = force_operand (x, NULL_RTX);
467 else
469 y = gen_rtx_PLUS (GET_MODE (x), copy_to_reg (y), constant_term);
470 if (! memory_address_p (mode, y))
471 x = force_operand (x, NULL_RTX);
472 else
473 x = y;
477 else if (GET_CODE (x) == MULT || GET_CODE (x) == MINUS)
478 x = force_operand (x, NULL_RTX);
480 /* If we have a register that's an invalid address,
481 it must be a hard reg of the wrong class. Copy it to a pseudo. */
482 else if (REG_P (x))
483 x = copy_to_reg (x);
485 /* Last resort: copy the value to a register, since
486 the register is a valid address. */
487 else
488 x = force_reg (Pmode, x);
491 done:
493 gcc_assert (memory_address_p (mode, x));
494 /* If we didn't change the address, we are done. Otherwise, mark
495 a reg as a pointer if we have REG or REG + CONST_INT. */
496 if (oldx == x)
497 return x;
498 else if (REG_P (x))
499 mark_reg_pointer (x, BITS_PER_UNIT);
500 else if (GET_CODE (x) == PLUS
501 && REG_P (XEXP (x, 0))
502 && GET_CODE (XEXP (x, 1)) == CONST_INT)
503 mark_reg_pointer (XEXP (x, 0), BITS_PER_UNIT);
505 /* OLDX may have been the address on a temporary. Update the address
506 to indicate that X is now used. */
507 update_temp_slot_address (oldx, x);
509 return x;
512 /* Convert a mem ref into one with a valid memory address.
513 Pass through anything else unchanged. */
516 validize_mem (rtx ref)
518 if (!MEM_P (ref))
519 return ref;
520 ref = use_anchored_address (ref);
521 if (memory_address_p (GET_MODE (ref), XEXP (ref, 0)))
522 return ref;
524 /* Don't alter REF itself, since that is probably a stack slot. */
525 return replace_equiv_address (ref, XEXP (ref, 0));
528 /* If X is a memory reference to a member of an object block, try rewriting
529 it to use an anchor instead. Return the new memory reference on success
530 and the old one on failure. */
533 use_anchored_address (rtx x)
535 rtx base;
536 HOST_WIDE_INT offset;
538 if (!flag_section_anchors)
539 return x;
541 if (!MEM_P (x))
542 return x;
544 /* Split the address into a base and offset. */
545 base = XEXP (x, 0);
546 offset = 0;
547 if (GET_CODE (base) == CONST
548 && GET_CODE (XEXP (base, 0)) == PLUS
549 && GET_CODE (XEXP (XEXP (base, 0), 1)) == CONST_INT)
551 offset += INTVAL (XEXP (XEXP (base, 0), 1));
552 base = XEXP (XEXP (base, 0), 0);
555 /* Check whether BASE is suitable for anchors. */
556 if (GET_CODE (base) != SYMBOL_REF
557 || !SYMBOL_REF_HAS_BLOCK_INFO_P (base)
558 || SYMBOL_REF_ANCHOR_P (base)
559 || SYMBOL_REF_BLOCK (base) == NULL
560 || !targetm.use_anchors_for_symbol_p (base))
561 return x;
563 /* Decide where BASE is going to be. */
564 place_block_symbol (base);
566 /* Get the anchor we need to use. */
567 offset += SYMBOL_REF_BLOCK_OFFSET (base);
568 base = get_section_anchor (SYMBOL_REF_BLOCK (base), offset,
569 SYMBOL_REF_TLS_MODEL (base));
571 /* Work out the offset from the anchor. */
572 offset -= SYMBOL_REF_BLOCK_OFFSET (base);
574 /* If we're going to run a CSE pass, force the anchor into a register.
575 We will then be able to reuse registers for several accesses, if the
576 target costs say that that's worthwhile. */
577 if (!cse_not_expected)
578 base = force_reg (GET_MODE (base), base);
580 return replace_equiv_address (x, plus_constant (base, offset));
583 /* Copy the value or contents of X to a new temp reg and return that reg. */
586 copy_to_reg (rtx x)
588 rtx temp = gen_reg_rtx (GET_MODE (x));
590 /* If not an operand, must be an address with PLUS and MULT so
591 do the computation. */
592 if (! general_operand (x, VOIDmode))
593 x = force_operand (x, temp);
595 if (x != temp)
596 emit_move_insn (temp, x);
598 return temp;
601 /* Like copy_to_reg but always give the new register mode Pmode
602 in case X is a constant. */
605 copy_addr_to_reg (rtx x)
607 return copy_to_mode_reg (Pmode, x);
610 /* Like copy_to_reg but always give the new register mode MODE
611 in case X is a constant. */
614 copy_to_mode_reg (enum machine_mode mode, rtx x)
616 rtx temp = gen_reg_rtx (mode);
618 /* If not an operand, must be an address with PLUS and MULT so
619 do the computation. */
620 if (! general_operand (x, VOIDmode))
621 x = force_operand (x, temp);
623 gcc_assert (GET_MODE (x) == mode || GET_MODE (x) == VOIDmode);
624 if (x != temp)
625 emit_move_insn (temp, x);
626 return temp;
629 /* Load X into a register if it is not already one.
630 Use mode MODE for the register.
631 X should be valid for mode MODE, but it may be a constant which
632 is valid for all integer modes; that's why caller must specify MODE.
634 The caller must not alter the value in the register we return,
635 since we mark it as a "constant" register. */
638 force_reg (enum machine_mode mode, rtx x)
640 rtx temp, insn, set;
642 if (REG_P (x))
643 return x;
645 if (general_operand (x, mode))
647 temp = gen_reg_rtx (mode);
648 insn = emit_move_insn (temp, x);
650 else
652 temp = force_operand (x, NULL_RTX);
653 if (REG_P (temp))
654 insn = get_last_insn ();
655 else
657 rtx temp2 = gen_reg_rtx (mode);
658 insn = emit_move_insn (temp2, temp);
659 temp = temp2;
663 /* Let optimizers know that TEMP's value never changes
664 and that X can be substituted for it. Don't get confused
665 if INSN set something else (such as a SUBREG of TEMP). */
666 if (CONSTANT_P (x)
667 && (set = single_set (insn)) != 0
668 && SET_DEST (set) == temp
669 && ! rtx_equal_p (x, SET_SRC (set)))
670 set_unique_reg_note (insn, REG_EQUAL, x);
672 /* Let optimizers know that TEMP is a pointer, and if so, the
673 known alignment of that pointer. */
675 unsigned align = 0;
676 if (GET_CODE (x) == SYMBOL_REF)
678 align = BITS_PER_UNIT;
679 if (SYMBOL_REF_DECL (x) && DECL_P (SYMBOL_REF_DECL (x)))
680 align = DECL_ALIGN (SYMBOL_REF_DECL (x));
682 else if (GET_CODE (x) == LABEL_REF)
683 align = BITS_PER_UNIT;
684 else if (GET_CODE (x) == CONST
685 && GET_CODE (XEXP (x, 0)) == PLUS
686 && GET_CODE (XEXP (XEXP (x, 0), 0)) == SYMBOL_REF
687 && GET_CODE (XEXP (XEXP (x, 0), 1)) == CONST_INT)
689 rtx s = XEXP (XEXP (x, 0), 0);
690 rtx c = XEXP (XEXP (x, 0), 1);
691 unsigned sa, ca;
693 sa = BITS_PER_UNIT;
694 if (SYMBOL_REF_DECL (s) && DECL_P (SYMBOL_REF_DECL (s)))
695 sa = DECL_ALIGN (SYMBOL_REF_DECL (s));
697 ca = exact_log2 (INTVAL (c) & -INTVAL (c)) * BITS_PER_UNIT;
699 align = MIN (sa, ca);
702 if (align || (MEM_P (x) && MEM_POINTER (x)))
703 mark_reg_pointer (temp, align);
706 return temp;
709 /* If X is a memory ref, copy its contents to a new temp reg and return
710 that reg. Otherwise, return X. */
713 force_not_mem (rtx x)
715 rtx temp;
717 if (!MEM_P (x) || GET_MODE (x) == BLKmode)
718 return x;
720 temp = gen_reg_rtx (GET_MODE (x));
722 if (MEM_POINTER (x))
723 REG_POINTER (temp) = 1;
725 emit_move_insn (temp, x);
726 return temp;
729 /* Copy X to TARGET (if it's nonzero and a reg)
730 or to a new temp reg and return that reg.
731 MODE is the mode to use for X in case it is a constant. */
734 copy_to_suggested_reg (rtx x, rtx target, enum machine_mode mode)
736 rtx temp;
738 if (target && REG_P (target))
739 temp = target;
740 else
741 temp = gen_reg_rtx (mode);
743 emit_move_insn (temp, x);
744 return temp;
747 /* Return the mode to use to store a scalar of TYPE and MODE.
748 PUNSIGNEDP points to the signedness of the type and may be adjusted
749 to show what signedness to use on extension operations.
751 FOR_CALL is nonzero if this call is promoting args for a call. */
753 #if defined(PROMOTE_MODE) && !defined(PROMOTE_FUNCTION_MODE)
754 #define PROMOTE_FUNCTION_MODE PROMOTE_MODE
755 #endif
757 enum machine_mode
758 promote_mode (const_tree type, enum machine_mode mode, int *punsignedp,
759 int for_call ATTRIBUTE_UNUSED)
761 const enum tree_code code = TREE_CODE (type);
762 int unsignedp = *punsignedp;
764 #ifndef PROMOTE_MODE
765 if (! for_call)
766 return mode;
767 #endif
769 switch (code)
771 #ifdef PROMOTE_FUNCTION_MODE
772 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
773 case REAL_TYPE: case OFFSET_TYPE: case FIXED_POINT_TYPE:
774 #ifdef PROMOTE_MODE
775 if (for_call)
777 #endif
778 PROMOTE_FUNCTION_MODE (mode, unsignedp, type);
779 #ifdef PROMOTE_MODE
781 else
783 PROMOTE_MODE (mode, unsignedp, type);
785 #endif
786 break;
787 #endif
789 #ifdef POINTERS_EXTEND_UNSIGNED
790 case REFERENCE_TYPE:
791 case POINTER_TYPE:
792 mode = Pmode;
793 unsignedp = POINTERS_EXTEND_UNSIGNED;
794 break;
795 #endif
797 default:
798 break;
801 *punsignedp = unsignedp;
802 return mode;
805 /* Adjust the stack pointer by ADJUST (an rtx for a number of bytes).
806 This pops when ADJUST is positive. ADJUST need not be constant. */
808 void
809 adjust_stack (rtx adjust)
811 rtx temp;
813 if (adjust == const0_rtx)
814 return;
816 /* We expect all variable sized adjustments to be multiple of
817 PREFERRED_STACK_BOUNDARY. */
818 if (GET_CODE (adjust) == CONST_INT)
819 stack_pointer_delta -= INTVAL (adjust);
821 temp = expand_binop (Pmode,
822 #ifdef STACK_GROWS_DOWNWARD
823 add_optab,
824 #else
825 sub_optab,
826 #endif
827 stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
828 OPTAB_LIB_WIDEN);
830 if (temp != stack_pointer_rtx)
831 emit_move_insn (stack_pointer_rtx, temp);
834 /* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes).
835 This pushes when ADJUST is positive. ADJUST need not be constant. */
837 void
838 anti_adjust_stack (rtx adjust)
840 rtx temp;
842 if (adjust == const0_rtx)
843 return;
845 /* We expect all variable sized adjustments to be multiple of
846 PREFERRED_STACK_BOUNDARY. */
847 if (GET_CODE (adjust) == CONST_INT)
848 stack_pointer_delta += INTVAL (adjust);
850 temp = expand_binop (Pmode,
851 #ifdef STACK_GROWS_DOWNWARD
852 sub_optab,
853 #else
854 add_optab,
855 #endif
856 stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
857 OPTAB_LIB_WIDEN);
859 if (temp != stack_pointer_rtx)
860 emit_move_insn (stack_pointer_rtx, temp);
863 /* Round the size of a block to be pushed up to the boundary required
864 by this machine. SIZE is the desired size, which need not be constant. */
866 static rtx
867 round_push (rtx size)
869 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
871 if (align == 1)
872 return size;
874 if (GET_CODE (size) == CONST_INT)
876 HOST_WIDE_INT new_size = (INTVAL (size) + align - 1) / align * align;
878 if (INTVAL (size) != new_size)
879 size = GEN_INT (new_size);
881 else
883 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
884 but we know it can't. So add ourselves and then do
885 TRUNC_DIV_EXPR. */
886 size = expand_binop (Pmode, add_optab, size, GEN_INT (align - 1),
887 NULL_RTX, 1, OPTAB_LIB_WIDEN);
888 size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size, GEN_INT (align),
889 NULL_RTX, 1);
890 size = expand_mult (Pmode, size, GEN_INT (align), NULL_RTX, 1);
893 return size;
896 /* Save the stack pointer for the purpose in SAVE_LEVEL. PSAVE is a pointer
897 to a previously-created save area. If no save area has been allocated,
898 this function will allocate one. If a save area is specified, it
899 must be of the proper mode.
901 The insns are emitted after insn AFTER, if nonzero, otherwise the insns
902 are emitted at the current position. */
904 void
905 emit_stack_save (enum save_level save_level, rtx *psave, rtx after)
907 rtx sa = *psave;
908 /* The default is that we use a move insn and save in a Pmode object. */
909 rtx (*fcn) (rtx, rtx) = gen_move_insn;
910 enum machine_mode mode = STACK_SAVEAREA_MODE (save_level);
912 /* See if this machine has anything special to do for this kind of save. */
913 switch (save_level)
915 #ifdef HAVE_save_stack_block
916 case SAVE_BLOCK:
917 if (HAVE_save_stack_block)
918 fcn = gen_save_stack_block;
919 break;
920 #endif
921 #ifdef HAVE_save_stack_function
922 case SAVE_FUNCTION:
923 if (HAVE_save_stack_function)
924 fcn = gen_save_stack_function;
925 break;
926 #endif
927 #ifdef HAVE_save_stack_nonlocal
928 case SAVE_NONLOCAL:
929 if (HAVE_save_stack_nonlocal)
930 fcn = gen_save_stack_nonlocal;
931 break;
932 #endif
933 default:
934 break;
937 /* If there is no save area and we have to allocate one, do so. Otherwise
938 verify the save area is the proper mode. */
940 if (sa == 0)
942 if (mode != VOIDmode)
944 if (save_level == SAVE_NONLOCAL)
945 *psave = sa = assign_stack_local (mode, GET_MODE_SIZE (mode), 0);
946 else
947 *psave = sa = gen_reg_rtx (mode);
951 if (after)
953 rtx seq;
955 start_sequence ();
956 do_pending_stack_adjust ();
957 /* We must validize inside the sequence, to ensure that any instructions
958 created by the validize call also get moved to the right place. */
959 if (sa != 0)
960 sa = validize_mem (sa);
961 emit_insn (fcn (sa, stack_pointer_rtx));
962 seq = get_insns ();
963 end_sequence ();
964 emit_insn_after (seq, after);
966 else
968 do_pending_stack_adjust ();
969 if (sa != 0)
970 sa = validize_mem (sa);
971 emit_insn (fcn (sa, stack_pointer_rtx));
975 /* Restore the stack pointer for the purpose in SAVE_LEVEL. SA is the save
976 area made by emit_stack_save. If it is zero, we have nothing to do.
978 Put any emitted insns after insn AFTER, if nonzero, otherwise at
979 current position. */
981 void
982 emit_stack_restore (enum save_level save_level, rtx sa, rtx after)
984 /* The default is that we use a move insn. */
985 rtx (*fcn) (rtx, rtx) = gen_move_insn;
987 /* See if this machine has anything special to do for this kind of save. */
988 switch (save_level)
990 #ifdef HAVE_restore_stack_block
991 case SAVE_BLOCK:
992 if (HAVE_restore_stack_block)
993 fcn = gen_restore_stack_block;
994 break;
995 #endif
996 #ifdef HAVE_restore_stack_function
997 case SAVE_FUNCTION:
998 if (HAVE_restore_stack_function)
999 fcn = gen_restore_stack_function;
1000 break;
1001 #endif
1002 #ifdef HAVE_restore_stack_nonlocal
1003 case SAVE_NONLOCAL:
1004 if (HAVE_restore_stack_nonlocal)
1005 fcn = gen_restore_stack_nonlocal;
1006 break;
1007 #endif
1008 default:
1009 break;
1012 if (sa != 0)
1014 sa = validize_mem (sa);
1015 /* These clobbers prevent the scheduler from moving
1016 references to variable arrays below the code
1017 that deletes (pops) the arrays. */
1018 emit_clobber (gen_rtx_MEM (BLKmode, gen_rtx_SCRATCH (VOIDmode)));
1019 emit_clobber (gen_rtx_MEM (BLKmode, stack_pointer_rtx));
1022 discard_pending_stack_adjust ();
1024 if (after)
1026 rtx seq;
1028 start_sequence ();
1029 emit_insn (fcn (stack_pointer_rtx, sa));
1030 seq = get_insns ();
1031 end_sequence ();
1032 emit_insn_after (seq, after);
1034 else
1035 emit_insn (fcn (stack_pointer_rtx, sa));
1038 /* Invoke emit_stack_save on the nonlocal_goto_save_area for the current
1039 function. This function should be called whenever we allocate or
1040 deallocate dynamic stack space. */
1042 void
1043 update_nonlocal_goto_save_area (void)
1045 tree t_save;
1046 rtx r_save;
1048 /* The nonlocal_goto_save_area object is an array of N pointers. The
1049 first one is used for the frame pointer save; the rest are sized by
1050 STACK_SAVEAREA_MODE. Create a reference to array index 1, the first
1051 of the stack save area slots. */
1052 t_save = build4 (ARRAY_REF, ptr_type_node, cfun->nonlocal_goto_save_area,
1053 integer_one_node, NULL_TREE, NULL_TREE);
1054 r_save = expand_expr (t_save, NULL_RTX, VOIDmode, EXPAND_WRITE);
1056 emit_stack_save (SAVE_NONLOCAL, &r_save, NULL_RTX);
1059 /* Return an rtx representing the address of an area of memory dynamically
1060 pushed on the stack. This region of memory is always aligned to
1061 a multiple of BIGGEST_ALIGNMENT.
1063 Any required stack pointer alignment is preserved.
1065 SIZE is an rtx representing the size of the area.
1066 TARGET is a place in which the address can be placed.
1068 KNOWN_ALIGN is the alignment (in bits) that we know SIZE has. */
1071 allocate_dynamic_stack_space (rtx size, rtx target, int known_align)
1073 /* If we're asking for zero bytes, it doesn't matter what we point
1074 to since we can't dereference it. But return a reasonable
1075 address anyway. */
1076 if (size == const0_rtx)
1077 return virtual_stack_dynamic_rtx;
1079 /* Otherwise, show we're calling alloca or equivalent. */
1080 cfun->calls_alloca = 1;
1082 /* Ensure the size is in the proper mode. */
1083 if (GET_MODE (size) != VOIDmode && GET_MODE (size) != Pmode)
1084 size = convert_to_mode (Pmode, size, 1);
1086 /* We can't attempt to minimize alignment necessary, because we don't
1087 know the final value of preferred_stack_boundary yet while executing
1088 this code. */
1089 crtl->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
1091 /* We will need to ensure that the address we return is aligned to
1092 BIGGEST_ALIGNMENT. If STACK_DYNAMIC_OFFSET is defined, we don't
1093 always know its final value at this point in the compilation (it
1094 might depend on the size of the outgoing parameter lists, for
1095 example), so we must align the value to be returned in that case.
1096 (Note that STACK_DYNAMIC_OFFSET will have a default nonzero value if
1097 STACK_POINTER_OFFSET or ACCUMULATE_OUTGOING_ARGS are defined).
1098 We must also do an alignment operation on the returned value if
1099 the stack pointer alignment is less strict that BIGGEST_ALIGNMENT.
1101 If we have to align, we must leave space in SIZE for the hole
1102 that might result from the alignment operation. */
1104 #if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET)
1105 #define MUST_ALIGN 1
1106 #else
1107 #define MUST_ALIGN (PREFERRED_STACK_BOUNDARY < BIGGEST_ALIGNMENT)
1108 #endif
1110 if (MUST_ALIGN)
1111 size
1112 = force_operand (plus_constant (size,
1113 BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1),
1114 NULL_RTX);
1116 #ifdef SETJMP_VIA_SAVE_AREA
1117 /* If setjmp restores regs from a save area in the stack frame,
1118 avoid clobbering the reg save area. Note that the offset of
1119 virtual_incoming_args_rtx includes the preallocated stack args space.
1120 It would be no problem to clobber that, but it's on the wrong side
1121 of the old save area.
1123 What used to happen is that, since we did not know for sure
1124 whether setjmp() was invoked until after RTL generation, we
1125 would use reg notes to store the "optimized" size and fix things
1126 up later. These days we know this information before we ever
1127 start building RTL so the reg notes are unnecessary. */
1128 if (!cfun->calls_setjmp)
1130 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
1132 /* ??? Code below assumes that the save area needs maximal
1133 alignment. This constraint may be too strong. */
1134 gcc_assert (PREFERRED_STACK_BOUNDARY == BIGGEST_ALIGNMENT);
1136 if (GET_CODE (size) == CONST_INT)
1138 HOST_WIDE_INT new_size = INTVAL (size) / align * align;
1140 if (INTVAL (size) != new_size)
1141 size = GEN_INT (new_size);
1143 else
1145 /* Since we know overflow is not possible, we avoid using
1146 CEIL_DIV_EXPR and use TRUNC_DIV_EXPR instead. */
1147 size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size,
1148 GEN_INT (align), NULL_RTX, 1);
1149 size = expand_mult (Pmode, size,
1150 GEN_INT (align), NULL_RTX, 1);
1153 else
1155 rtx dynamic_offset
1156 = expand_binop (Pmode, sub_optab, virtual_stack_dynamic_rtx,
1157 stack_pointer_rtx, NULL_RTX, 1, OPTAB_LIB_WIDEN);
1159 size = expand_binop (Pmode, add_optab, size, dynamic_offset,
1160 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1162 #endif /* SETJMP_VIA_SAVE_AREA */
1164 /* Round the size to a multiple of the required stack alignment.
1165 Since the stack if presumed to be rounded before this allocation,
1166 this will maintain the required alignment.
1168 If the stack grows downward, we could save an insn by subtracting
1169 SIZE from the stack pointer and then aligning the stack pointer.
1170 The problem with this is that the stack pointer may be unaligned
1171 between the execution of the subtraction and alignment insns and
1172 some machines do not allow this. Even on those that do, some
1173 signal handlers malfunction if a signal should occur between those
1174 insns. Since this is an extremely rare event, we have no reliable
1175 way of knowing which systems have this problem. So we avoid even
1176 momentarily mis-aligning the stack. */
1178 /* If we added a variable amount to SIZE,
1179 we can no longer assume it is aligned. */
1180 #if !defined (SETJMP_VIA_SAVE_AREA)
1181 if (MUST_ALIGN || known_align % PREFERRED_STACK_BOUNDARY != 0)
1182 #endif
1183 size = round_push (size);
1185 do_pending_stack_adjust ();
1187 /* We ought to be called always on the toplevel and stack ought to be aligned
1188 properly. */
1189 gcc_assert (!(stack_pointer_delta
1190 % (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT)));
1192 /* If needed, check that we have the required amount of stack.
1193 Take into account what has already been checked. */
1194 if (flag_stack_check == GENERIC_STACK_CHECK)
1195 probe_stack_range (STACK_OLD_CHECK_PROTECT + STACK_CHECK_MAX_FRAME_SIZE,
1196 size);
1197 else if (flag_stack_check == STATIC_BUILTIN_STACK_CHECK)
1198 probe_stack_range (STACK_CHECK_PROTECT, size);
1200 /* Don't use a TARGET that isn't a pseudo or is the wrong mode. */
1201 if (target == 0 || !REG_P (target)
1202 || REGNO (target) < FIRST_PSEUDO_REGISTER
1203 || GET_MODE (target) != Pmode)
1204 target = gen_reg_rtx (Pmode);
1206 mark_reg_pointer (target, known_align);
1208 /* Perform the required allocation from the stack. Some systems do
1209 this differently than simply incrementing/decrementing from the
1210 stack pointer, such as acquiring the space by calling malloc(). */
1211 #ifdef HAVE_allocate_stack
1212 if (HAVE_allocate_stack)
1214 enum machine_mode mode = STACK_SIZE_MODE;
1215 insn_operand_predicate_fn pred;
1217 /* We don't have to check against the predicate for operand 0 since
1218 TARGET is known to be a pseudo of the proper mode, which must
1219 be valid for the operand. For operand 1, convert to the
1220 proper mode and validate. */
1221 if (mode == VOIDmode)
1222 mode = insn_data[(int) CODE_FOR_allocate_stack].operand[1].mode;
1224 pred = insn_data[(int) CODE_FOR_allocate_stack].operand[1].predicate;
1225 if (pred && ! ((*pred) (size, mode)))
1226 size = copy_to_mode_reg (mode, convert_to_mode (mode, size, 1));
1228 emit_insn (gen_allocate_stack (target, size));
1230 else
1231 #endif
1233 #ifndef STACK_GROWS_DOWNWARD
1234 emit_move_insn (target, virtual_stack_dynamic_rtx);
1235 #endif
1237 /* Check stack bounds if necessary. */
1238 if (crtl->limit_stack)
1240 rtx available;
1241 rtx space_available = gen_label_rtx ();
1242 #ifdef STACK_GROWS_DOWNWARD
1243 available = expand_binop (Pmode, sub_optab,
1244 stack_pointer_rtx, stack_limit_rtx,
1245 NULL_RTX, 1, OPTAB_WIDEN);
1246 #else
1247 available = expand_binop (Pmode, sub_optab,
1248 stack_limit_rtx, stack_pointer_rtx,
1249 NULL_RTX, 1, OPTAB_WIDEN);
1250 #endif
1251 emit_cmp_and_jump_insns (available, size, GEU, NULL_RTX, Pmode, 1,
1252 space_available);
1253 #ifdef HAVE_trap
1254 if (HAVE_trap)
1255 emit_insn (gen_trap ());
1256 else
1257 #endif
1258 error ("stack limits not supported on this target");
1259 emit_barrier ();
1260 emit_label (space_available);
1263 anti_adjust_stack (size);
1265 #ifdef STACK_GROWS_DOWNWARD
1266 emit_move_insn (target, virtual_stack_dynamic_rtx);
1267 #endif
1270 if (MUST_ALIGN)
1272 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
1273 but we know it can't. So add ourselves and then do
1274 TRUNC_DIV_EXPR. */
1275 target = expand_binop (Pmode, add_optab, target,
1276 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1),
1277 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1278 target = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, target,
1279 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT),
1280 NULL_RTX, 1);
1281 target = expand_mult (Pmode, target,
1282 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT),
1283 NULL_RTX, 1);
1286 /* Record the new stack level for nonlocal gotos. */
1287 if (cfun->nonlocal_goto_save_area != 0)
1288 update_nonlocal_goto_save_area ();
1290 return target;
1293 /* A front end may want to override GCC's stack checking by providing a
1294 run-time routine to call to check the stack, so provide a mechanism for
1295 calling that routine. */
1297 static GTY(()) rtx stack_check_libfunc;
1299 void
1300 set_stack_check_libfunc (rtx libfunc)
1302 stack_check_libfunc = libfunc;
1305 /* Emit one stack probe at ADDRESS, an address within the stack. */
1307 static void
1308 emit_stack_probe (rtx address)
1310 rtx memref = gen_rtx_MEM (word_mode, address);
1312 MEM_VOLATILE_P (memref) = 1;
1314 if (STACK_CHECK_PROBE_LOAD)
1315 emit_move_insn (gen_reg_rtx (word_mode), memref);
1316 else
1317 emit_move_insn (memref, const0_rtx);
1320 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
1321 FIRST is a constant and size is a Pmode RTX. These are offsets from the
1322 current stack pointer. STACK_GROWS_DOWNWARD says whether to add or
1323 subtract from the stack. If SIZE is constant, this is done
1324 with a fixed number of probes. Otherwise, we must make a loop. */
1326 #ifdef STACK_GROWS_DOWNWARD
1327 #define STACK_GROW_OP MINUS
1328 #else
1329 #define STACK_GROW_OP PLUS
1330 #endif
1332 void
1333 probe_stack_range (HOST_WIDE_INT first, rtx size)
1335 /* First ensure SIZE is Pmode. */
1336 if (GET_MODE (size) != VOIDmode && GET_MODE (size) != Pmode)
1337 size = convert_to_mode (Pmode, size, 1);
1339 /* Next see if the front end has set up a function for us to call to
1340 check the stack. */
1341 if (stack_check_libfunc != 0)
1343 rtx addr = memory_address (QImode,
1344 gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1345 stack_pointer_rtx,
1346 plus_constant (size, first)));
1348 addr = convert_memory_address (ptr_mode, addr);
1349 emit_library_call (stack_check_libfunc, LCT_NORMAL, VOIDmode, 1, addr,
1350 ptr_mode);
1353 /* Next see if we have an insn to check the stack. Use it if so. */
1354 #ifdef HAVE_check_stack
1355 else if (HAVE_check_stack)
1357 insn_operand_predicate_fn pred;
1358 rtx last_addr
1359 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1360 stack_pointer_rtx,
1361 plus_constant (size, first)),
1362 NULL_RTX);
1364 pred = insn_data[(int) CODE_FOR_check_stack].operand[0].predicate;
1365 if (pred && ! ((*pred) (last_addr, Pmode)))
1366 last_addr = copy_to_mode_reg (Pmode, last_addr);
1368 emit_insn (gen_check_stack (last_addr));
1370 #endif
1372 /* If we have to generate explicit probes, see if we have a constant
1373 small number of them to generate. If so, that's the easy case. */
1374 else if (GET_CODE (size) == CONST_INT
1375 && INTVAL (size) < 10 * STACK_CHECK_PROBE_INTERVAL)
1377 HOST_WIDE_INT offset;
1379 /* Start probing at FIRST + N * STACK_CHECK_PROBE_INTERVAL
1380 for values of N from 1 until it exceeds LAST. If only one
1381 probe is needed, this will not generate any code. Then probe
1382 at LAST. */
1383 for (offset = first + STACK_CHECK_PROBE_INTERVAL;
1384 offset < INTVAL (size);
1385 offset = offset + STACK_CHECK_PROBE_INTERVAL)
1386 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1387 stack_pointer_rtx,
1388 GEN_INT (offset)));
1390 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1391 stack_pointer_rtx,
1392 plus_constant (size, first)));
1395 /* In the variable case, do the same as above, but in a loop. We emit loop
1396 notes so that loop optimization can be done. */
1397 else
1399 rtx test_addr
1400 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1401 stack_pointer_rtx,
1402 GEN_INT (first + STACK_CHECK_PROBE_INTERVAL)),
1403 NULL_RTX);
1404 rtx last_addr
1405 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1406 stack_pointer_rtx,
1407 plus_constant (size, first)),
1408 NULL_RTX);
1409 rtx incr = GEN_INT (STACK_CHECK_PROBE_INTERVAL);
1410 rtx loop_lab = gen_label_rtx ();
1411 rtx test_lab = gen_label_rtx ();
1412 rtx end_lab = gen_label_rtx ();
1413 rtx temp;
1415 if (!REG_P (test_addr)
1416 || REGNO (test_addr) < FIRST_PSEUDO_REGISTER)
1417 test_addr = force_reg (Pmode, test_addr);
1419 emit_jump (test_lab);
1421 emit_label (loop_lab);
1422 emit_stack_probe (test_addr);
1424 #ifdef STACK_GROWS_DOWNWARD
1425 #define CMP_OPCODE GTU
1426 temp = expand_binop (Pmode, sub_optab, test_addr, incr, test_addr,
1427 1, OPTAB_WIDEN);
1428 #else
1429 #define CMP_OPCODE LTU
1430 temp = expand_binop (Pmode, add_optab, test_addr, incr, test_addr,
1431 1, OPTAB_WIDEN);
1432 #endif
1434 gcc_assert (temp == test_addr);
1436 emit_label (test_lab);
1437 emit_cmp_and_jump_insns (test_addr, last_addr, CMP_OPCODE,
1438 NULL_RTX, Pmode, 1, loop_lab);
1439 emit_jump (end_lab);
1440 emit_label (end_lab);
1442 emit_stack_probe (last_addr);
1446 /* Return an rtx representing the register or memory location
1447 in which a scalar value of data type VALTYPE
1448 was returned by a function call to function FUNC.
1449 FUNC is a FUNCTION_DECL, FNTYPE a FUNCTION_TYPE node if the precise
1450 function is known, otherwise 0.
1451 OUTGOING is 1 if on a machine with register windows this function
1452 should return the register in which the function will put its result
1453 and 0 otherwise. */
1456 hard_function_value (const_tree valtype, const_tree func, const_tree fntype,
1457 int outgoing ATTRIBUTE_UNUSED)
1459 rtx val;
1461 val = targetm.calls.function_value (valtype, func ? func : fntype, outgoing);
1463 if (REG_P (val)
1464 && GET_MODE (val) == BLKmode)
1466 unsigned HOST_WIDE_INT bytes = int_size_in_bytes (valtype);
1467 enum machine_mode tmpmode;
1469 /* int_size_in_bytes can return -1. We don't need a check here
1470 since the value of bytes will then be large enough that no
1471 mode will match anyway. */
1473 for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
1474 tmpmode != VOIDmode;
1475 tmpmode = GET_MODE_WIDER_MODE (tmpmode))
1477 /* Have we found a large enough mode? */
1478 if (GET_MODE_SIZE (tmpmode) >= bytes)
1479 break;
1482 /* No suitable mode found. */
1483 gcc_assert (tmpmode != VOIDmode);
1485 PUT_MODE (val, tmpmode);
1487 return val;
1490 /* Return an rtx representing the register or memory location
1491 in which a scalar value of mode MODE was returned by a library call. */
1494 hard_libcall_value (enum machine_mode mode)
1496 return LIBCALL_VALUE (mode);
1499 /* Look up the tree code for a given rtx code
1500 to provide the arithmetic operation for REAL_ARITHMETIC.
1501 The function returns an int because the caller may not know
1502 what `enum tree_code' means. */
1505 rtx_to_tree_code (enum rtx_code code)
1507 enum tree_code tcode;
1509 switch (code)
1511 case PLUS:
1512 tcode = PLUS_EXPR;
1513 break;
1514 case MINUS:
1515 tcode = MINUS_EXPR;
1516 break;
1517 case MULT:
1518 tcode = MULT_EXPR;
1519 break;
1520 case DIV:
1521 tcode = RDIV_EXPR;
1522 break;
1523 case SMIN:
1524 tcode = MIN_EXPR;
1525 break;
1526 case SMAX:
1527 tcode = MAX_EXPR;
1528 break;
1529 default:
1530 tcode = LAST_AND_UNUSED_TREE_CODE;
1531 break;
1533 return ((int) tcode);
1536 #include "gt-explow.h"