1 /* Subroutines for manipulating rtx's in semantically interesting ways.
2 Copyright (C) 1987, 1991, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
32 #include "hard-reg-set.h"
33 #include "insn-config.h"
36 #if !defined PREFERRED_STACK_BOUNDARY && defined STACK_BOUNDARY
37 #define PREFERRED_STACK_BOUNDARY STACK_BOUNDARY
40 static rtx break_out_memory_refs PARAMS ((rtx));
41 static void emit_stack_probe PARAMS ((rtx));
44 /* Truncate and perhaps sign-extend C as appropriate for MODE. */
47 trunc_int_for_mode (c, mode)
49 enum machine_mode mode;
51 int width = GET_MODE_BITSIZE (mode);
53 /* Canonicalize BImode to 0 and STORE_FLAG_VALUE. */
55 return c & 1 ? STORE_FLAG_VALUE : 0;
57 /* Sign-extend for the requested mode. */
59 if (width < HOST_BITS_PER_WIDE_INT)
61 HOST_WIDE_INT sign = 1;
71 /* Return an rtx for the sum of X and the integer C.
73 This function should be used via the `plus_constant' macro. */
76 plus_constant_wide (x, c)
78 register HOST_WIDE_INT c;
80 register RTX_CODE code;
81 register enum machine_mode mode;
95 return GEN_INT (INTVAL (x) + c);
99 unsigned HOST_WIDE_INT l1 = CONST_DOUBLE_LOW (x);
100 HOST_WIDE_INT h1 = CONST_DOUBLE_HIGH (x);
101 unsigned HOST_WIDE_INT l2 = c;
102 HOST_WIDE_INT h2 = c < 0 ? ~0 : 0;
103 unsigned HOST_WIDE_INT lv;
106 add_double (l1, h1, l2, h2, &lv, &hv);
108 return immed_double_const (lv, hv, VOIDmode);
112 /* If this is a reference to the constant pool, try replacing it with
113 a reference to a new constant. If the resulting address isn't
114 valid, don't return it because we have no way to validize it. */
115 if (GET_CODE (XEXP (x, 0)) == SYMBOL_REF
116 && CONSTANT_POOL_ADDRESS_P (XEXP (x, 0)))
119 = force_const_mem (GET_MODE (x),
120 plus_constant (get_pool_constant (XEXP (x, 0)),
122 if (memory_address_p (GET_MODE (tem), XEXP (tem, 0)))
128 /* If adding to something entirely constant, set a flag
129 so that we can add a CONST around the result. */
140 /* The interesting case is adding the integer to a sum.
141 Look for constant term in the sum and combine
142 with C. For an integer constant term, we make a combined
143 integer. For a constant term that is not an explicit integer,
144 we cannot really combine, but group them together anyway.
146 Restart or use a recursive call in case the remaining operand is
147 something that we handle specially, such as a SYMBOL_REF.
149 We may not immediately return from the recursive call here, lest
150 all_constant gets lost. */
152 if (GET_CODE (XEXP (x, 1)) == CONST_INT)
154 c += INTVAL (XEXP (x, 1));
156 if (GET_MODE (x) != VOIDmode)
157 c = trunc_int_for_mode (c, GET_MODE (x));
162 else if (CONSTANT_P (XEXP (x, 0)))
164 x = gen_rtx_PLUS (mode,
165 plus_constant (XEXP (x, 0), c),
169 else if (CONSTANT_P (XEXP (x, 1)))
171 x = gen_rtx_PLUS (mode,
173 plus_constant (XEXP (x, 1), c));
183 x = gen_rtx_PLUS (mode, x, GEN_INT (c));
185 if (GET_CODE (x) == SYMBOL_REF || GET_CODE (x) == LABEL_REF)
187 else if (all_constant)
188 return gen_rtx_CONST (mode, x);
193 /* This is the same as `plus_constant', except that it handles LO_SUM.
195 This function should be used via the `plus_constant_for_output' macro. */
198 plus_constant_for_output_wide (x, c)
200 register HOST_WIDE_INT c;
202 register enum machine_mode mode = GET_MODE (x);
204 if (GET_CODE (x) == LO_SUM)
205 return gen_rtx_LO_SUM (mode, XEXP (x, 0),
206 plus_constant_for_output (XEXP (x, 1), c));
209 return plus_constant (x, c);
212 /* If X is a sum, return a new sum like X but lacking any constant terms.
213 Add all the removed constant terms into *CONSTPTR.
214 X itself is not altered. The result != X if and only if
215 it is not isomorphic to X. */
218 eliminate_constant_term (x, constptr)
225 if (GET_CODE (x) != PLUS)
228 /* First handle constants appearing at this level explicitly. */
229 if (GET_CODE (XEXP (x, 1)) == CONST_INT
230 && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x), *constptr,
232 && GET_CODE (tem) == CONST_INT)
235 return eliminate_constant_term (XEXP (x, 0), constptr);
239 x0 = eliminate_constant_term (XEXP (x, 0), &tem);
240 x1 = eliminate_constant_term (XEXP (x, 1), &tem);
241 if ((x1 != XEXP (x, 1) || x0 != XEXP (x, 0))
242 && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x),
244 && GET_CODE (tem) == CONST_INT)
247 return gen_rtx_PLUS (GET_MODE (x), x0, x1);
253 /* Returns the insn that next references REG after INSN, or 0
254 if REG is clobbered before next referenced or we cannot find
255 an insn that references REG in a straight-line piece of code. */
258 find_next_ref (reg, insn)
264 for (insn = NEXT_INSN (insn); insn; insn = next)
266 next = NEXT_INSN (insn);
267 if (GET_CODE (insn) == NOTE)
269 if (GET_CODE (insn) == CODE_LABEL
270 || GET_CODE (insn) == BARRIER)
272 if (GET_CODE (insn) == INSN
273 || GET_CODE (insn) == JUMP_INSN
274 || GET_CODE (insn) == CALL_INSN)
276 if (reg_set_p (reg, insn))
278 if (reg_mentioned_p (reg, PATTERN (insn)))
280 if (GET_CODE (insn) == JUMP_INSN)
282 if (any_uncondjump_p (insn))
283 next = JUMP_LABEL (insn);
287 if (GET_CODE (insn) == CALL_INSN
288 && REGNO (reg) < FIRST_PSEUDO_REGISTER
289 && call_used_regs[REGNO (reg)])
298 /* Return an rtx for the size in bytes of the value of EXP. */
306 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'd'
307 && DECL_SIZE_UNIT (exp) != 0)
308 size = DECL_SIZE_UNIT (exp);
310 size = size_in_bytes (TREE_TYPE (exp));
312 if (TREE_CODE (size) != INTEGER_CST
313 && contains_placeholder_p (size))
314 size = build (WITH_RECORD_EXPR, sizetype, size, exp);
316 return expand_expr (size, NULL_RTX, TYPE_MODE (sizetype),
317 EXPAND_MEMORY_USE_BAD);
320 /* Return a copy of X in which all memory references
321 and all constants that involve symbol refs
322 have been replaced with new temporary registers.
323 Also emit code to load the memory locations and constants
324 into those registers.
326 If X contains no such constants or memory references,
327 X itself (not a copy) is returned.
329 If a constant is found in the address that is not a legitimate constant
330 in an insn, it is left alone in the hope that it might be valid in the
333 X may contain no arithmetic except addition, subtraction and multiplication.
334 Values returned by expand_expr with 1 for sum_ok fit this constraint. */
337 break_out_memory_refs (x)
340 if (GET_CODE (x) == MEM
341 || (CONSTANT_P (x) && CONSTANT_ADDRESS_P (x)
342 && GET_MODE (x) != VOIDmode))
343 x = force_reg (GET_MODE (x), x);
344 else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS
345 || GET_CODE (x) == MULT)
347 register rtx op0 = break_out_memory_refs (XEXP (x, 0));
348 register rtx op1 = break_out_memory_refs (XEXP (x, 1));
350 if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1))
351 x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1);
357 #ifdef POINTERS_EXTEND_UNSIGNED
359 /* Given X, a memory address in ptr_mode, convert it to an address
360 in Pmode, or vice versa (TO_MODE says which way). We take advantage of
361 the fact that pointers are not allowed to overflow by commuting arithmetic
362 operations over conversions so that address arithmetic insns can be
366 convert_memory_address (to_mode, x)
367 enum machine_mode to_mode;
370 enum machine_mode from_mode = to_mode == ptr_mode ? Pmode : ptr_mode;
373 /* Here we handle some special cases. If none of them apply, fall through
374 to the default case. */
375 switch (GET_CODE (x))
382 if (GET_MODE (SUBREG_REG (x)) == to_mode)
383 return SUBREG_REG (x);
387 temp = gen_rtx_LABEL_REF (to_mode, XEXP (x, 0));
388 LABEL_REF_NONLOCAL_P (temp) = LABEL_REF_NONLOCAL_P (x);
392 temp = gen_rtx_SYMBOL_REF (to_mode, XSTR (x, 0));
393 SYMBOL_REF_FLAG (temp) = SYMBOL_REF_FLAG (x);
394 CONSTANT_POOL_ADDRESS_P (temp) = CONSTANT_POOL_ADDRESS_P (x);
395 STRING_POOL_ADDRESS_P (temp) = STRING_POOL_ADDRESS_P (x);
399 return gen_rtx_CONST (to_mode,
400 convert_memory_address (to_mode, XEXP (x, 0)));
404 /* For addition the second operand is a small constant, we can safely
405 permute the conversion and addition operation. We can always safely
406 permute them if we are making the address narrower. In addition,
407 always permute the operations if this is a constant. */
408 if (GET_MODE_SIZE (to_mode) < GET_MODE_SIZE (from_mode)
409 || (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == CONST_INT
410 && (INTVAL (XEXP (x, 1)) + 20000 < 40000
411 || CONSTANT_P (XEXP (x, 0)))))
412 return gen_rtx_fmt_ee (GET_CODE (x), to_mode,
413 convert_memory_address (to_mode, XEXP (x, 0)),
414 convert_memory_address (to_mode, XEXP (x, 1)));
421 return convert_modes (to_mode, from_mode,
422 x, POINTERS_EXTEND_UNSIGNED);
426 /* Given a memory address or facsimile X, construct a new address,
427 currently equivalent, that is stable: future stores won't change it.
429 X must be composed of constants, register and memory references
430 combined with addition, subtraction and multiplication:
431 in other words, just what you can get from expand_expr if sum_ok is 1.
433 Works by making copies of all regs and memory locations used
434 by X and combining them the same way X does.
435 You could also stabilize the reference to this address
436 by copying the address to a register with copy_to_reg;
437 but then you wouldn't get indexed addressing in the reference. */
443 if (GET_CODE (x) == REG)
445 if (REGNO (x) != FRAME_POINTER_REGNUM
446 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
447 && REGNO (x) != HARD_FRAME_POINTER_REGNUM
452 else if (GET_CODE (x) == MEM)
454 else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS
455 || GET_CODE (x) == MULT)
457 register rtx op0 = copy_all_regs (XEXP (x, 0));
458 register rtx op1 = copy_all_regs (XEXP (x, 1));
459 if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1))
460 x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1);
465 /* Return something equivalent to X but valid as a memory address
466 for something of mode MODE. When X is not itself valid, this
467 works by copying X or subexpressions of it into registers. */
470 memory_address (mode, x)
471 enum machine_mode mode;
474 register rtx oldx = x;
476 if (GET_CODE (x) == ADDRESSOF)
479 #ifdef POINTERS_EXTEND_UNSIGNED
480 if (GET_MODE (x) == ptr_mode)
481 x = convert_memory_address (Pmode, x);
484 /* By passing constant addresses thru registers
485 we get a chance to cse them. */
486 if (! cse_not_expected && CONSTANT_P (x) && CONSTANT_ADDRESS_P (x))
487 x = force_reg (Pmode, x);
489 /* Accept a QUEUED that refers to a REG
490 even though that isn't a valid address.
491 On attempting to put this in an insn we will call protect_from_queue
492 which will turn it into a REG, which is valid. */
493 else if (GET_CODE (x) == QUEUED
494 && GET_CODE (QUEUED_VAR (x)) == REG)
497 /* We get better cse by rejecting indirect addressing at this stage.
498 Let the combiner create indirect addresses where appropriate.
499 For now, generate the code so that the subexpressions useful to share
500 are visible. But not if cse won't be done! */
503 if (! cse_not_expected && GET_CODE (x) != REG)
504 x = break_out_memory_refs (x);
506 /* At this point, any valid address is accepted. */
507 GO_IF_LEGITIMATE_ADDRESS (mode, x, win);
509 /* If it was valid before but breaking out memory refs invalidated it,
510 use it the old way. */
511 if (memory_address_p (mode, oldx))
514 /* Perform machine-dependent transformations on X
515 in certain cases. This is not necessary since the code
516 below can handle all possible cases, but machine-dependent
517 transformations can make better code. */
518 LEGITIMIZE_ADDRESS (x, oldx, mode, win);
520 /* PLUS and MULT can appear in special ways
521 as the result of attempts to make an address usable for indexing.
522 Usually they are dealt with by calling force_operand, below.
523 But a sum containing constant terms is special
524 if removing them makes the sum a valid address:
525 then we generate that address in a register
526 and index off of it. We do this because it often makes
527 shorter code, and because the addresses thus generated
528 in registers often become common subexpressions. */
529 if (GET_CODE (x) == PLUS)
531 rtx constant_term = const0_rtx;
532 rtx y = eliminate_constant_term (x, &constant_term);
533 if (constant_term == const0_rtx
534 || ! memory_address_p (mode, y))
535 x = force_operand (x, NULL_RTX);
538 y = gen_rtx_PLUS (GET_MODE (x), copy_to_reg (y), constant_term);
539 if (! memory_address_p (mode, y))
540 x = force_operand (x, NULL_RTX);
546 else if (GET_CODE (x) == MULT || GET_CODE (x) == MINUS)
547 x = force_operand (x, NULL_RTX);
549 /* If we have a register that's an invalid address,
550 it must be a hard reg of the wrong class. Copy it to a pseudo. */
551 else if (GET_CODE (x) == REG)
554 /* Last resort: copy the value to a register, since
555 the register is a valid address. */
557 x = force_reg (Pmode, x);
564 if (flag_force_addr && ! cse_not_expected && GET_CODE (x) != REG
565 /* Don't copy an addr via a reg if it is one of our stack slots. */
566 && ! (GET_CODE (x) == PLUS
567 && (XEXP (x, 0) == virtual_stack_vars_rtx
568 || XEXP (x, 0) == virtual_incoming_args_rtx)))
570 if (general_operand (x, Pmode))
571 x = force_reg (Pmode, x);
573 x = force_operand (x, NULL_RTX);
579 /* If we didn't change the address, we are done. Otherwise, mark
580 a reg as a pointer if we have REG or REG + CONST_INT. */
583 else if (GET_CODE (x) == REG)
584 mark_reg_pointer (x, BITS_PER_UNIT);
585 else if (GET_CODE (x) == PLUS
586 && GET_CODE (XEXP (x, 0)) == REG
587 && GET_CODE (XEXP (x, 1)) == CONST_INT)
588 mark_reg_pointer (XEXP (x, 0), BITS_PER_UNIT);
590 /* OLDX may have been the address on a temporary. Update the address
591 to indicate that X is now used. */
592 update_temp_slot_address (oldx, x);
597 /* Like `memory_address' but pretend `flag_force_addr' is 0. */
600 memory_address_noforce (mode, x)
601 enum machine_mode mode;
604 int ambient_force_addr = flag_force_addr;
608 val = memory_address (mode, x);
609 flag_force_addr = ambient_force_addr;
613 /* Convert a mem ref into one with a valid memory address.
614 Pass through anything else unchanged. */
620 if (GET_CODE (ref) != MEM)
622 if (memory_address_p (GET_MODE (ref), XEXP (ref, 0)))
624 /* Don't alter REF itself, since that is probably a stack slot. */
625 return change_address (ref, GET_MODE (ref), XEXP (ref, 0));
628 /* Given REF, either a MEM or a REG, and T, either the type of X or
629 the expression corresponding to REF, set RTX_UNCHANGING_P if
633 maybe_set_unchanging (ref, t)
637 /* We can set RTX_UNCHANGING_P from TREE_READONLY for decls whose
638 initialization is only executed once, or whose initializer always
639 has the same value. Currently we simplify this to PARM_DECLs in the
640 first case, and decls with TREE_CONSTANT initializers in the second. */
641 if ((TREE_READONLY (t) && DECL_P (t)
642 && (TREE_CODE (t) == PARM_DECL
643 || DECL_INITIAL (t) == NULL_TREE
644 || TREE_CONSTANT (DECL_INITIAL (t))))
645 || TREE_CODE_CLASS (TREE_CODE (t)) == 'c')
646 RTX_UNCHANGING_P (ref) = 1;
649 /* Given REF, a MEM, and T, either the type of X or the expression
650 corresponding to REF, set the memory attributes. OBJECTP is nonzero
651 if we are making a new object of this type. */
654 set_mem_attributes (ref, t, objectp)
661 /* It can happen that type_for_mode was given a mode for which there
662 is no language-level type. In which case it returns NULL, which
667 type = TYPE_P (t) ? t : TREE_TYPE (t);
669 /* Get the alias set from the expression or type (perhaps using a
670 front-end routine) and then copy bits from the type. */
672 /* It is incorrect to set RTX_UNCHANGING_P from TREE_READONLY (type)
673 here, because, in C and C++, the fact that a location is accessed
674 through a const expression does not mean that the value there can
676 MEM_ALIAS_SET (ref) = get_alias_set (t);
677 MEM_VOLATILE_P (ref) = TYPE_VOLATILE (type);
678 MEM_IN_STRUCT_P (ref) = AGGREGATE_TYPE_P (type);
680 /* If we are making an object of this type, we know that it is a scalar if
681 the type is not an aggregate. */
682 if (objectp && ! AGGREGATE_TYPE_P (type))
683 MEM_SCALAR_P (ref) = 1;
685 /* If T is a type, this is all we can do. Otherwise, we may be able
686 to deduce some more information about the expression. */
690 maybe_set_unchanging (ref, t);
691 if (TREE_THIS_VOLATILE (t))
692 MEM_VOLATILE_P (ref) = 1;
694 /* Now see if we can say more about whether it's an aggregate or
695 scalar. If we already know it's an aggregate, don't bother. */
696 if (MEM_IN_STRUCT_P (ref))
699 /* Now remove any NOPs: they don't change what the underlying object is.
700 Likewise for SAVE_EXPR. */
701 while (TREE_CODE (t) == NOP_EXPR || TREE_CODE (t) == CONVERT_EXPR
702 || TREE_CODE (t) == NON_LVALUE_EXPR || TREE_CODE (t) == SAVE_EXPR)
703 t = TREE_OPERAND (t, 0);
705 /* Since we already know the type isn't an aggregate, if this is a decl,
706 it must be a scalar. Or if it is a reference into an aggregate,
707 this is part of an aggregate. Otherwise we don't know. */
709 MEM_SCALAR_P (ref) = 1;
710 else if (TREE_CODE (t) == COMPONENT_REF || TREE_CODE (t) == ARRAY_REF
711 || TREE_CODE (t) == ARRAY_RANGE_REF
712 || TREE_CODE (t) == BIT_FIELD_REF)
713 MEM_IN_STRUCT_P (ref) = 1;
716 /* Return a modified copy of X with its memory address copied
717 into a temporary register to protect it from side effects.
718 If X is not a MEM, it is returned unchanged (and not copied).
719 Perhaps even if it is a MEM, if there is no need to change it. */
727 if (GET_CODE (x) != MEM)
731 if (rtx_unstable_p (addr))
733 rtx temp = force_reg (Pmode, copy_all_regs (addr));
734 rtx mem = gen_rtx_MEM (GET_MODE (x), temp);
736 MEM_COPY_ATTRIBUTES (mem, x);
742 /* Copy the value or contents of X to a new temp reg and return that reg. */
748 register rtx temp = gen_reg_rtx (GET_MODE (x));
750 /* If not an operand, must be an address with PLUS and MULT so
751 do the computation. */
752 if (! general_operand (x, VOIDmode))
753 x = force_operand (x, temp);
756 emit_move_insn (temp, x);
761 /* Like copy_to_reg but always give the new register mode Pmode
762 in case X is a constant. */
768 return copy_to_mode_reg (Pmode, x);
771 /* Like copy_to_reg but always give the new register mode MODE
772 in case X is a constant. */
775 copy_to_mode_reg (mode, x)
776 enum machine_mode mode;
779 register rtx temp = gen_reg_rtx (mode);
781 /* If not an operand, must be an address with PLUS and MULT so
782 do the computation. */
783 if (! general_operand (x, VOIDmode))
784 x = force_operand (x, temp);
786 if (GET_MODE (x) != mode && GET_MODE (x) != VOIDmode)
789 emit_move_insn (temp, x);
793 /* Load X into a register if it is not already one.
794 Use mode MODE for the register.
795 X should be valid for mode MODE, but it may be a constant which
796 is valid for all integer modes; that's why caller must specify MODE.
798 The caller must not alter the value in the register we return,
799 since we mark it as a "constant" register. */
803 enum machine_mode mode;
806 register rtx temp, insn, set;
808 if (GET_CODE (x) == REG)
811 temp = gen_reg_rtx (mode);
813 if (! general_operand (x, mode))
814 x = force_operand (x, NULL_RTX);
816 insn = emit_move_insn (temp, x);
818 /* Let optimizers know that TEMP's value never changes
819 and that X can be substituted for it. Don't get confused
820 if INSN set something else (such as a SUBREG of TEMP). */
822 && (set = single_set (insn)) != 0
823 && SET_DEST (set) == temp)
825 rtx note = find_reg_note (insn, REG_EQUAL, NULL_RTX);
830 REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_EQUAL, x, REG_NOTES (insn));
835 /* If X is a memory ref, copy its contents to a new temp reg and return
836 that reg. Otherwise, return X. */
844 if (GET_CODE (x) != MEM || GET_MODE (x) == BLKmode)
847 temp = gen_reg_rtx (GET_MODE (x));
848 emit_move_insn (temp, x);
852 /* Copy X to TARGET (if it's nonzero and a reg)
853 or to a new temp reg and return that reg.
854 MODE is the mode to use for X in case it is a constant. */
857 copy_to_suggested_reg (x, target, mode)
859 enum machine_mode mode;
863 if (target && GET_CODE (target) == REG)
866 temp = gen_reg_rtx (mode);
868 emit_move_insn (temp, x);
872 /* Return the mode to use to store a scalar of TYPE and MODE.
873 PUNSIGNEDP points to the signedness of the type and may be adjusted
874 to show what signedness to use on extension operations.
876 FOR_CALL is non-zero if this call is promoting args for a call. */
879 promote_mode (type, mode, punsignedp, for_call)
881 enum machine_mode mode;
883 int for_call ATTRIBUTE_UNUSED;
885 enum tree_code code = TREE_CODE (type);
886 int unsignedp = *punsignedp;
888 #ifdef PROMOTE_FOR_CALL_ONLY
896 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
897 case CHAR_TYPE: case REAL_TYPE: case OFFSET_TYPE:
898 PROMOTE_MODE (mode, unsignedp, type);
902 #ifdef POINTERS_EXTEND_UNSIGNED
906 unsignedp = POINTERS_EXTEND_UNSIGNED;
914 *punsignedp = unsignedp;
918 /* Adjust the stack pointer by ADJUST (an rtx for a number of bytes).
919 This pops when ADJUST is positive. ADJUST need not be constant. */
922 adjust_stack (adjust)
926 adjust = protect_from_queue (adjust, 0);
928 if (adjust == const0_rtx)
931 /* We expect all variable sized adjustments to be multiple of
932 PREFERRED_STACK_BOUNDARY. */
933 if (GET_CODE (adjust) == CONST_INT)
934 stack_pointer_delta -= INTVAL (adjust);
936 temp = expand_binop (Pmode,
937 #ifdef STACK_GROWS_DOWNWARD
942 stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
945 if (temp != stack_pointer_rtx)
946 emit_move_insn (stack_pointer_rtx, temp);
949 /* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes).
950 This pushes when ADJUST is positive. ADJUST need not be constant. */
953 anti_adjust_stack (adjust)
957 adjust = protect_from_queue (adjust, 0);
959 if (adjust == const0_rtx)
962 /* We expect all variable sized adjustments to be multiple of
963 PREFERRED_STACK_BOUNDARY. */
964 if (GET_CODE (adjust) == CONST_INT)
965 stack_pointer_delta += INTVAL (adjust);
967 temp = expand_binop (Pmode,
968 #ifdef STACK_GROWS_DOWNWARD
973 stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
976 if (temp != stack_pointer_rtx)
977 emit_move_insn (stack_pointer_rtx, temp);
980 /* Round the size of a block to be pushed up to the boundary required
981 by this machine. SIZE is the desired size, which need not be constant. */
987 #ifdef PREFERRED_STACK_BOUNDARY
988 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
991 if (GET_CODE (size) == CONST_INT)
993 int new = (INTVAL (size) + align - 1) / align * align;
994 if (INTVAL (size) != new)
995 size = GEN_INT (new);
999 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
1000 but we know it can't. So add ourselves and then do
1002 size = expand_binop (Pmode, add_optab, size, GEN_INT (align - 1),
1003 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1004 size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size, GEN_INT (align),
1006 size = expand_mult (Pmode, size, GEN_INT (align), NULL_RTX, 1);
1008 #endif /* PREFERRED_STACK_BOUNDARY */
1012 /* Save the stack pointer for the purpose in SAVE_LEVEL. PSAVE is a pointer
1013 to a previously-created save area. If no save area has been allocated,
1014 this function will allocate one. If a save area is specified, it
1015 must be of the proper mode.
1017 The insns are emitted after insn AFTER, if nonzero, otherwise the insns
1018 are emitted at the current position. */
1021 emit_stack_save (save_level, psave, after)
1022 enum save_level save_level;
1027 /* The default is that we use a move insn and save in a Pmode object. */
1028 rtx (*fcn) PARAMS ((rtx, rtx)) = gen_move_insn;
1029 enum machine_mode mode = STACK_SAVEAREA_MODE (save_level);
1031 /* See if this machine has anything special to do for this kind of save. */
1034 #ifdef HAVE_save_stack_block
1036 if (HAVE_save_stack_block)
1037 fcn = gen_save_stack_block;
1040 #ifdef HAVE_save_stack_function
1042 if (HAVE_save_stack_function)
1043 fcn = gen_save_stack_function;
1046 #ifdef HAVE_save_stack_nonlocal
1048 if (HAVE_save_stack_nonlocal)
1049 fcn = gen_save_stack_nonlocal;
1056 /* If there is no save area and we have to allocate one, do so. Otherwise
1057 verify the save area is the proper mode. */
1061 if (mode != VOIDmode)
1063 if (save_level == SAVE_NONLOCAL)
1064 *psave = sa = assign_stack_local (mode, GET_MODE_SIZE (mode), 0);
1066 *psave = sa = gen_reg_rtx (mode);
1071 if (mode == VOIDmode || GET_MODE (sa) != mode)
1080 /* We must validize inside the sequence, to ensure that any instructions
1081 created by the validize call also get moved to the right place. */
1083 sa = validize_mem (sa);
1084 emit_insn (fcn (sa, stack_pointer_rtx));
1085 seq = gen_sequence ();
1087 emit_insn_after (seq, after);
1092 sa = validize_mem (sa);
1093 emit_insn (fcn (sa, stack_pointer_rtx));
1097 /* Restore the stack pointer for the purpose in SAVE_LEVEL. SA is the save
1098 area made by emit_stack_save. If it is zero, we have nothing to do.
1100 Put any emitted insns after insn AFTER, if nonzero, otherwise at
1101 current position. */
1104 emit_stack_restore (save_level, sa, after)
1105 enum save_level save_level;
1109 /* The default is that we use a move insn. */
1110 rtx (*fcn) PARAMS ((rtx, rtx)) = gen_move_insn;
1112 /* See if this machine has anything special to do for this kind of save. */
1115 #ifdef HAVE_restore_stack_block
1117 if (HAVE_restore_stack_block)
1118 fcn = gen_restore_stack_block;
1121 #ifdef HAVE_restore_stack_function
1123 if (HAVE_restore_stack_function)
1124 fcn = gen_restore_stack_function;
1127 #ifdef HAVE_restore_stack_nonlocal
1129 if (HAVE_restore_stack_nonlocal)
1130 fcn = gen_restore_stack_nonlocal;
1138 sa = validize_mem (sa);
1145 emit_insn (fcn (stack_pointer_rtx, sa));
1146 seq = gen_sequence ();
1148 emit_insn_after (seq, after);
1151 emit_insn (fcn (stack_pointer_rtx, sa));
1154 #ifdef SETJMP_VIA_SAVE_AREA
1155 /* Optimize RTL generated by allocate_dynamic_stack_space for targets
1156 where SETJMP_VIA_SAVE_AREA is true. The problem is that on these
1157 platforms, the dynamic stack space used can corrupt the original
1158 frame, thus causing a crash if a longjmp unwinds to it. */
1161 optimize_save_area_alloca (insns)
1166 for (insn = insns; insn; insn = NEXT_INSN(insn))
1170 if (GET_CODE (insn) != INSN)
1173 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
1175 if (REG_NOTE_KIND (note) != REG_SAVE_AREA)
1178 if (!current_function_calls_setjmp)
1180 rtx pat = PATTERN (insn);
1182 /* If we do not see the note in a pattern matching
1183 these precise characteristics, we did something
1184 entirely wrong in allocate_dynamic_stack_space.
1186 Note, one way this could happen is if SETJMP_VIA_SAVE_AREA
1187 was defined on a machine where stacks grow towards higher
1190 Right now only supported port with stack that grow upward
1191 is the HPPA and it does not define SETJMP_VIA_SAVE_AREA. */
1192 if (GET_CODE (pat) != SET
1193 || SET_DEST (pat) != stack_pointer_rtx
1194 || GET_CODE (SET_SRC (pat)) != MINUS
1195 || XEXP (SET_SRC (pat), 0) != stack_pointer_rtx)
1198 /* This will now be transformed into a (set REG REG)
1199 so we can just blow away all the other notes. */
1200 XEXP (SET_SRC (pat), 1) = XEXP (note, 0);
1201 REG_NOTES (insn) = NULL_RTX;
1205 /* setjmp was called, we must remove the REG_SAVE_AREA
1206 note so that later passes do not get confused by its
1208 if (note == REG_NOTES (insn))
1210 REG_NOTES (insn) = XEXP (note, 1);
1216 for (srch = REG_NOTES (insn); srch; srch = XEXP (srch, 1))
1217 if (XEXP (srch, 1) == note)
1220 if (srch == NULL_RTX)
1223 XEXP (srch, 1) = XEXP (note, 1);
1226 /* Once we've seen the note of interest, we need not look at
1227 the rest of them. */
1232 #endif /* SETJMP_VIA_SAVE_AREA */
1234 /* Return an rtx representing the address of an area of memory dynamically
1235 pushed on the stack. This region of memory is always aligned to
1236 a multiple of BIGGEST_ALIGNMENT.
1238 Any required stack pointer alignment is preserved.
1240 SIZE is an rtx representing the size of the area.
1241 TARGET is a place in which the address can be placed.
1243 KNOWN_ALIGN is the alignment (in bits) that we know SIZE has. */
1246 allocate_dynamic_stack_space (size, target, known_align)
1251 #ifdef SETJMP_VIA_SAVE_AREA
1252 rtx setjmpless_size = NULL_RTX;
1255 /* If we're asking for zero bytes, it doesn't matter what we point
1256 to since we can't dereference it. But return a reasonable
1258 if (size == const0_rtx)
1259 return virtual_stack_dynamic_rtx;
1261 /* Otherwise, show we're calling alloca or equivalent. */
1262 current_function_calls_alloca = 1;
1264 /* Ensure the size is in the proper mode. */
1265 if (GET_MODE (size) != VOIDmode && GET_MODE (size) != Pmode)
1266 size = convert_to_mode (Pmode, size, 1);
1268 /* We can't attempt to minimize alignment necessary, because we don't
1269 know the final value of preferred_stack_boundary yet while executing
1271 #ifdef PREFERRED_STACK_BOUNDARY
1272 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
1275 /* We will need to ensure that the address we return is aligned to
1276 BIGGEST_ALIGNMENT. If STACK_DYNAMIC_OFFSET is defined, we don't
1277 always know its final value at this point in the compilation (it
1278 might depend on the size of the outgoing parameter lists, for
1279 example), so we must align the value to be returned in that case.
1280 (Note that STACK_DYNAMIC_OFFSET will have a default non-zero value if
1281 STACK_POINTER_OFFSET or ACCUMULATE_OUTGOING_ARGS are defined).
1282 We must also do an alignment operation on the returned value if
1283 the stack pointer alignment is less strict that BIGGEST_ALIGNMENT.
1285 If we have to align, we must leave space in SIZE for the hole
1286 that might result from the alignment operation. */
1288 #if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET) || ! defined (PREFERRED_STACK_BOUNDARY)
1289 #define MUST_ALIGN 1
1291 #define MUST_ALIGN (PREFERRED_STACK_BOUNDARY < BIGGEST_ALIGNMENT)
1296 = force_operand (plus_constant (size,
1297 BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1),
1300 #ifdef SETJMP_VIA_SAVE_AREA
1301 /* If setjmp restores regs from a save area in the stack frame,
1302 avoid clobbering the reg save area. Note that the offset of
1303 virtual_incoming_args_rtx includes the preallocated stack args space.
1304 It would be no problem to clobber that, but it's on the wrong side
1305 of the old save area. */
1308 = expand_binop (Pmode, sub_optab, virtual_stack_dynamic_rtx,
1309 stack_pointer_rtx, NULL_RTX, 1, OPTAB_LIB_WIDEN);
1311 if (!current_function_calls_setjmp)
1313 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
1315 /* See optimize_save_area_alloca to understand what is being
1318 #if !defined(PREFERRED_STACK_BOUNDARY) || !defined(MUST_ALIGN) || (PREFERRED_STACK_BOUNDARY != BIGGEST_ALIGNMENT)
1319 /* If anyone creates a target with these characteristics, let them
1320 know that our optimization cannot work correctly in such a case. */
1324 if (GET_CODE (size) == CONST_INT)
1326 HOST_WIDE_INT new = INTVAL (size) / align * align;
1328 if (INTVAL (size) != new)
1329 setjmpless_size = GEN_INT (new);
1331 setjmpless_size = size;
1335 /* Since we know overflow is not possible, we avoid using
1336 CEIL_DIV_EXPR and use TRUNC_DIV_EXPR instead. */
1337 setjmpless_size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size,
1338 GEN_INT (align), NULL_RTX, 1);
1339 setjmpless_size = expand_mult (Pmode, setjmpless_size,
1340 GEN_INT (align), NULL_RTX, 1);
1342 /* Our optimization works based upon being able to perform a simple
1343 transformation of this RTL into a (set REG REG) so make sure things
1344 did in fact end up in a REG. */
1345 if (!register_operand (setjmpless_size, Pmode))
1346 setjmpless_size = force_reg (Pmode, setjmpless_size);
1349 size = expand_binop (Pmode, add_optab, size, dynamic_offset,
1350 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1352 #endif /* SETJMP_VIA_SAVE_AREA */
1354 /* Round the size to a multiple of the required stack alignment.
1355 Since the stack if presumed to be rounded before this allocation,
1356 this will maintain the required alignment.
1358 If the stack grows downward, we could save an insn by subtracting
1359 SIZE from the stack pointer and then aligning the stack pointer.
1360 The problem with this is that the stack pointer may be unaligned
1361 between the execution of the subtraction and alignment insns and
1362 some machines do not allow this. Even on those that do, some
1363 signal handlers malfunction if a signal should occur between those
1364 insns. Since this is an extremely rare event, we have no reliable
1365 way of knowing which systems have this problem. So we avoid even
1366 momentarily mis-aligning the stack. */
1368 #ifdef PREFERRED_STACK_BOUNDARY
1369 /* If we added a variable amount to SIZE,
1370 we can no longer assume it is aligned. */
1371 #if !defined (SETJMP_VIA_SAVE_AREA)
1372 if (MUST_ALIGN || known_align % PREFERRED_STACK_BOUNDARY != 0)
1374 size = round_push (size);
1377 do_pending_stack_adjust ();
1379 /* We ought to be called always on the toplevel and stack ought to be aligned
1381 #ifdef PREFERRED_STACK_BOUNDARY
1382 if (stack_pointer_delta % (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT))
1386 /* If needed, check that we have the required amount of stack. Take into
1387 account what has already been checked. */
1388 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
1389 probe_stack_range (STACK_CHECK_MAX_FRAME_SIZE + STACK_CHECK_PROTECT, size);
1391 /* Don't use a TARGET that isn't a pseudo or is the wrong mode. */
1392 if (target == 0 || GET_CODE (target) != REG
1393 || REGNO (target) < FIRST_PSEUDO_REGISTER
1394 || GET_MODE (target) != Pmode)
1395 target = gen_reg_rtx (Pmode);
1397 mark_reg_pointer (target, known_align);
1399 /* Perform the required allocation from the stack. Some systems do
1400 this differently than simply incrementing/decrementing from the
1401 stack pointer, such as acquiring the space by calling malloc(). */
1402 #ifdef HAVE_allocate_stack
1403 if (HAVE_allocate_stack)
1405 enum machine_mode mode = STACK_SIZE_MODE;
1406 insn_operand_predicate_fn pred;
1408 pred = insn_data[(int) CODE_FOR_allocate_stack].operand[0].predicate;
1409 if (pred && ! ((*pred) (target, Pmode)))
1410 #ifdef POINTERS_EXTEND_UNSIGNED
1411 target = convert_memory_address (Pmode, target);
1413 target = copy_to_mode_reg (Pmode, target);
1416 if (mode == VOIDmode)
1419 pred = insn_data[(int) CODE_FOR_allocate_stack].operand[1].predicate;
1420 if (pred && ! ((*pred) (size, mode)))
1421 size = copy_to_mode_reg (mode, size);
1423 emit_insn (gen_allocate_stack (target, size));
1428 #ifndef STACK_GROWS_DOWNWARD
1429 emit_move_insn (target, virtual_stack_dynamic_rtx);
1432 /* Check stack bounds if necessary. */
1433 if (current_function_limit_stack)
1436 rtx space_available = gen_label_rtx ();
1437 #ifdef STACK_GROWS_DOWNWARD
1438 available = expand_binop (Pmode, sub_optab,
1439 stack_pointer_rtx, stack_limit_rtx,
1440 NULL_RTX, 1, OPTAB_WIDEN);
1442 available = expand_binop (Pmode, sub_optab,
1443 stack_limit_rtx, stack_pointer_rtx,
1444 NULL_RTX, 1, OPTAB_WIDEN);
1446 emit_cmp_and_jump_insns (available, size, GEU, NULL_RTX, Pmode, 1,
1447 0, space_available);
1450 emit_insn (gen_trap ());
1453 error ("stack limits not supported on this target");
1455 emit_label (space_available);
1458 anti_adjust_stack (size);
1459 #ifdef SETJMP_VIA_SAVE_AREA
1460 if (setjmpless_size != NULL_RTX)
1462 rtx note_target = get_last_insn ();
1464 REG_NOTES (note_target)
1465 = gen_rtx_EXPR_LIST (REG_SAVE_AREA, setjmpless_size,
1466 REG_NOTES (note_target));
1468 #endif /* SETJMP_VIA_SAVE_AREA */
1470 #ifdef STACK_GROWS_DOWNWARD
1471 emit_move_insn (target, virtual_stack_dynamic_rtx);
1477 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
1478 but we know it can't. So add ourselves and then do
1480 target = expand_binop (Pmode, add_optab, target,
1481 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1),
1482 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1483 target = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, target,
1484 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT),
1486 target = expand_mult (Pmode, target,
1487 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT),
1491 /* Some systems require a particular insn to refer to the stack
1492 to make the pages exist. */
1495 emit_insn (gen_probe ());
1498 /* Record the new stack level for nonlocal gotos. */
1499 if (nonlocal_goto_handler_slots != 0)
1500 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
1505 /* A front end may want to override GCC's stack checking by providing a
1506 run-time routine to call to check the stack, so provide a mechanism for
1507 calling that routine. */
1509 static rtx stack_check_libfunc;
1512 set_stack_check_libfunc (libfunc)
1515 stack_check_libfunc = libfunc;
1518 /* Emit one stack probe at ADDRESS, an address within the stack. */
1521 emit_stack_probe (address)
1524 rtx memref = gen_rtx_MEM (word_mode, address);
1526 MEM_VOLATILE_P (memref) = 1;
1528 if (STACK_CHECK_PROBE_LOAD)
1529 emit_move_insn (gen_reg_rtx (word_mode), memref);
1531 emit_move_insn (memref, const0_rtx);
1534 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
1535 FIRST is a constant and size is a Pmode RTX. These are offsets from the
1536 current stack pointer. STACK_GROWS_DOWNWARD says whether to add or
1537 subtract from the stack. If SIZE is constant, this is done
1538 with a fixed number of probes. Otherwise, we must make a loop. */
1540 #ifdef STACK_GROWS_DOWNWARD
1541 #define STACK_GROW_OP MINUS
1543 #define STACK_GROW_OP PLUS
1547 probe_stack_range (first, size)
1548 HOST_WIDE_INT first;
1551 /* First see if the front end has set up a function for us to call to
1553 if (stack_check_libfunc != 0)
1555 rtx addr = memory_address (QImode,
1556 gen_rtx (STACK_GROW_OP, Pmode,
1558 plus_constant (size, first)));
1560 #ifdef POINTERS_EXTEND_UNSIGNED
1561 if (GET_MODE (addr) != ptr_mode)
1562 addr = convert_memory_address (ptr_mode, addr);
1565 emit_library_call (stack_check_libfunc, 0, VOIDmode, 1, addr,
1569 /* Next see if we have an insn to check the stack. Use it if so. */
1570 #ifdef HAVE_check_stack
1571 else if (HAVE_check_stack)
1573 insn_operand_predicate_fn pred;
1575 = force_operand (gen_rtx_STACK_GROW_OP (Pmode,
1577 plus_constant (size, first)),
1580 pred = insn_data[(int) CODE_FOR_check_stack].operand[0].predicate;
1581 if (pred && ! ((*pred) (last_addr, Pmode)))
1582 last_addr = copy_to_mode_reg (Pmode, last_addr);
1584 emit_insn (gen_check_stack (last_addr));
1588 /* If we have to generate explicit probes, see if we have a constant
1589 small number of them to generate. If so, that's the easy case. */
1590 else if (GET_CODE (size) == CONST_INT
1591 && INTVAL (size) < 10 * STACK_CHECK_PROBE_INTERVAL)
1593 HOST_WIDE_INT offset;
1595 /* Start probing at FIRST + N * STACK_CHECK_PROBE_INTERVAL
1596 for values of N from 1 until it exceeds LAST. If only one
1597 probe is needed, this will not generate any code. Then probe
1599 for (offset = first + STACK_CHECK_PROBE_INTERVAL;
1600 offset < INTVAL (size);
1601 offset = offset + STACK_CHECK_PROBE_INTERVAL)
1602 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1606 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1608 plus_constant (size, first)));
1611 /* In the variable case, do the same as above, but in a loop. We emit loop
1612 notes so that loop optimization can be done. */
1616 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1618 GEN_INT (first + STACK_CHECK_PROBE_INTERVAL)),
1621 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1623 plus_constant (size, first)),
1625 rtx incr = GEN_INT (STACK_CHECK_PROBE_INTERVAL);
1626 rtx loop_lab = gen_label_rtx ();
1627 rtx test_lab = gen_label_rtx ();
1628 rtx end_lab = gen_label_rtx ();
1631 if (GET_CODE (test_addr) != REG
1632 || REGNO (test_addr) < FIRST_PSEUDO_REGISTER)
1633 test_addr = force_reg (Pmode, test_addr);
1635 emit_note (NULL, NOTE_INSN_LOOP_BEG);
1636 emit_jump (test_lab);
1638 emit_label (loop_lab);
1639 emit_stack_probe (test_addr);
1641 emit_note (NULL, NOTE_INSN_LOOP_CONT);
1643 #ifdef STACK_GROWS_DOWNWARD
1644 #define CMP_OPCODE GTU
1645 temp = expand_binop (Pmode, sub_optab, test_addr, incr, test_addr,
1648 #define CMP_OPCODE LTU
1649 temp = expand_binop (Pmode, add_optab, test_addr, incr, test_addr,
1653 if (temp != test_addr)
1656 emit_label (test_lab);
1657 emit_cmp_and_jump_insns (test_addr, last_addr, CMP_OPCODE,
1658 NULL_RTX, Pmode, 1, 0, loop_lab);
1659 emit_jump (end_lab);
1660 emit_note (NULL, NOTE_INSN_LOOP_END);
1661 emit_label (end_lab);
1663 emit_stack_probe (last_addr);
1667 /* Return an rtx representing the register or memory location
1668 in which a scalar value of data type VALTYPE
1669 was returned by a function call to function FUNC.
1670 FUNC is a FUNCTION_DECL node if the precise function is known,
1672 OUTGOING is 1 if on a machine with register windows this function
1673 should return the register in which the function will put its result
1677 hard_function_value (valtype, func, outgoing)
1679 tree func ATTRIBUTE_UNUSED;
1680 int outgoing ATTRIBUTE_UNUSED;
1684 #ifdef FUNCTION_OUTGOING_VALUE
1686 val = FUNCTION_OUTGOING_VALUE (valtype, func);
1689 val = FUNCTION_VALUE (valtype, func);
1691 if (GET_CODE (val) == REG
1692 && GET_MODE (val) == BLKmode)
1694 unsigned HOST_WIDE_INT bytes = int_size_in_bytes (valtype);
1695 enum machine_mode tmpmode;
1697 for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
1698 tmpmode != VOIDmode;
1699 tmpmode = GET_MODE_WIDER_MODE (tmpmode))
1701 /* Have we found a large enough mode? */
1702 if (GET_MODE_SIZE (tmpmode) >= bytes)
1706 /* No suitable mode found. */
1707 if (tmpmode == VOIDmode)
1710 PUT_MODE (val, tmpmode);
1715 /* Return an rtx representing the register or memory location
1716 in which a scalar value of mode MODE was returned by a library call. */
1719 hard_libcall_value (mode)
1720 enum machine_mode mode;
1722 return LIBCALL_VALUE (mode);
1725 /* Look up the tree code for a given rtx code
1726 to provide the arithmetic operation for REAL_ARITHMETIC.
1727 The function returns an int because the caller may not know
1728 what `enum tree_code' means. */
1731 rtx_to_tree_code (code)
1734 enum tree_code tcode;
1757 tcode = LAST_AND_UNUSED_TREE_CODE;
1760 return ((int) tcode);