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. */
304 tree size = size_in_bytes (TREE_TYPE (exp));
306 if (TREE_CODE (size) != INTEGER_CST
307 && contains_placeholder_p (size))
308 size = build (WITH_RECORD_EXPR, sizetype, size, exp);
310 return expand_expr (size, NULL_RTX, TYPE_MODE (sizetype),
311 EXPAND_MEMORY_USE_BAD);
314 /* Return a copy of X in which all memory references
315 and all constants that involve symbol refs
316 have been replaced with new temporary registers.
317 Also emit code to load the memory locations and constants
318 into those registers.
320 If X contains no such constants or memory references,
321 X itself (not a copy) is returned.
323 If a constant is found in the address that is not a legitimate constant
324 in an insn, it is left alone in the hope that it might be valid in the
327 X may contain no arithmetic except addition, subtraction and multiplication.
328 Values returned by expand_expr with 1 for sum_ok fit this constraint. */
331 break_out_memory_refs (x)
334 if (GET_CODE (x) == MEM
335 || (CONSTANT_P (x) && CONSTANT_ADDRESS_P (x)
336 && GET_MODE (x) != VOIDmode))
337 x = force_reg (GET_MODE (x), x);
338 else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS
339 || GET_CODE (x) == MULT)
341 register rtx op0 = break_out_memory_refs (XEXP (x, 0));
342 register rtx op1 = break_out_memory_refs (XEXP (x, 1));
344 if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1))
345 x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1);
351 #ifdef POINTERS_EXTEND_UNSIGNED
353 /* Given X, a memory address in ptr_mode, convert it to an address
354 in Pmode, or vice versa (TO_MODE says which way). We take advantage of
355 the fact that pointers are not allowed to overflow by commuting arithmetic
356 operations over conversions so that address arithmetic insns can be
360 convert_memory_address (to_mode, x)
361 enum machine_mode to_mode;
364 enum machine_mode from_mode = to_mode == ptr_mode ? Pmode : ptr_mode;
367 /* Here we handle some special cases. If none of them apply, fall through
368 to the default case. */
369 switch (GET_CODE (x))
376 if (GET_MODE (SUBREG_REG (x)) == to_mode)
377 return SUBREG_REG (x);
381 temp = gen_rtx_LABEL_REF (to_mode, XEXP (x, 0));
382 LABEL_REF_NONLOCAL_P (temp) = LABEL_REF_NONLOCAL_P (x);
386 temp = gen_rtx_SYMBOL_REF (to_mode, XSTR (x, 0));
387 SYMBOL_REF_FLAG (temp) = SYMBOL_REF_FLAG (x);
388 CONSTANT_POOL_ADDRESS_P (temp) = CONSTANT_POOL_ADDRESS_P (x);
389 STRING_POOL_ADDRESS_P (temp) = STRING_POOL_ADDRESS_P (x);
393 return gen_rtx_CONST (to_mode,
394 convert_memory_address (to_mode, XEXP (x, 0)));
398 /* For addition the second operand is a small constant, we can safely
399 permute the conversion and addition operation. We can always safely
400 permute them if we are making the address narrower. In addition,
401 always permute the operations if this is a constant. */
402 if (GET_MODE_SIZE (to_mode) < GET_MODE_SIZE (from_mode)
403 || (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == CONST_INT
404 && (INTVAL (XEXP (x, 1)) + 20000 < 40000
405 || CONSTANT_P (XEXP (x, 0)))))
406 return gen_rtx_fmt_ee (GET_CODE (x), to_mode,
407 convert_memory_address (to_mode, XEXP (x, 0)),
408 convert_memory_address (to_mode, XEXP (x, 1)));
415 return convert_modes (to_mode, from_mode,
416 x, POINTERS_EXTEND_UNSIGNED);
420 /* Given a memory address or facsimile X, construct a new address,
421 currently equivalent, that is stable: future stores won't change it.
423 X must be composed of constants, register and memory references
424 combined with addition, subtraction and multiplication:
425 in other words, just what you can get from expand_expr if sum_ok is 1.
427 Works by making copies of all regs and memory locations used
428 by X and combining them the same way X does.
429 You could also stabilize the reference to this address
430 by copying the address to a register with copy_to_reg;
431 but then you wouldn't get indexed addressing in the reference. */
437 if (GET_CODE (x) == REG)
439 if (REGNO (x) != FRAME_POINTER_REGNUM
440 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
441 && REGNO (x) != HARD_FRAME_POINTER_REGNUM
446 else if (GET_CODE (x) == MEM)
448 else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS
449 || GET_CODE (x) == MULT)
451 register rtx op0 = copy_all_regs (XEXP (x, 0));
452 register rtx op1 = copy_all_regs (XEXP (x, 1));
453 if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1))
454 x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1);
459 /* Return something equivalent to X but valid as a memory address
460 for something of mode MODE. When X is not itself valid, this
461 works by copying X or subexpressions of it into registers. */
464 memory_address (mode, x)
465 enum machine_mode mode;
468 register rtx oldx = x;
470 if (GET_CODE (x) == ADDRESSOF)
473 #ifdef POINTERS_EXTEND_UNSIGNED
474 if (GET_MODE (x) == ptr_mode)
475 x = convert_memory_address (Pmode, x);
478 /* By passing constant addresses thru registers
479 we get a chance to cse them. */
480 if (! cse_not_expected && CONSTANT_P (x) && CONSTANT_ADDRESS_P (x))
481 x = force_reg (Pmode, x);
483 /* Accept a QUEUED that refers to a REG
484 even though that isn't a valid address.
485 On attempting to put this in an insn we will call protect_from_queue
486 which will turn it into a REG, which is valid. */
487 else if (GET_CODE (x) == QUEUED
488 && GET_CODE (QUEUED_VAR (x)) == REG)
491 /* We get better cse by rejecting indirect addressing at this stage.
492 Let the combiner create indirect addresses where appropriate.
493 For now, generate the code so that the subexpressions useful to share
494 are visible. But not if cse won't be done! */
497 if (! cse_not_expected && GET_CODE (x) != REG)
498 x = break_out_memory_refs (x);
500 /* At this point, any valid address is accepted. */
501 GO_IF_LEGITIMATE_ADDRESS (mode, x, win);
503 /* If it was valid before but breaking out memory refs invalidated it,
504 use it the old way. */
505 if (memory_address_p (mode, oldx))
508 /* Perform machine-dependent transformations on X
509 in certain cases. This is not necessary since the code
510 below can handle all possible cases, but machine-dependent
511 transformations can make better code. */
512 LEGITIMIZE_ADDRESS (x, oldx, mode, win);
514 /* PLUS and MULT can appear in special ways
515 as the result of attempts to make an address usable for indexing.
516 Usually they are dealt with by calling force_operand, below.
517 But a sum containing constant terms is special
518 if removing them makes the sum a valid address:
519 then we generate that address in a register
520 and index off of it. We do this because it often makes
521 shorter code, and because the addresses thus generated
522 in registers often become common subexpressions. */
523 if (GET_CODE (x) == PLUS)
525 rtx constant_term = const0_rtx;
526 rtx y = eliminate_constant_term (x, &constant_term);
527 if (constant_term == const0_rtx
528 || ! memory_address_p (mode, y))
529 x = force_operand (x, NULL_RTX);
532 y = gen_rtx_PLUS (GET_MODE (x), copy_to_reg (y), constant_term);
533 if (! memory_address_p (mode, y))
534 x = force_operand (x, NULL_RTX);
540 else if (GET_CODE (x) == MULT || GET_CODE (x) == MINUS)
541 x = force_operand (x, NULL_RTX);
543 /* If we have a register that's an invalid address,
544 it must be a hard reg of the wrong class. Copy it to a pseudo. */
545 else if (GET_CODE (x) == REG)
548 /* Last resort: copy the value to a register, since
549 the register is a valid address. */
551 x = force_reg (Pmode, x);
558 if (flag_force_addr && ! cse_not_expected && GET_CODE (x) != REG
559 /* Don't copy an addr via a reg if it is one of our stack slots. */
560 && ! (GET_CODE (x) == PLUS
561 && (XEXP (x, 0) == virtual_stack_vars_rtx
562 || XEXP (x, 0) == virtual_incoming_args_rtx)))
564 if (general_operand (x, Pmode))
565 x = force_reg (Pmode, x);
567 x = force_operand (x, NULL_RTX);
573 /* If we didn't change the address, we are done. Otherwise, mark
574 a reg as a pointer if we have REG or REG + CONST_INT. */
577 else if (GET_CODE (x) == REG)
578 mark_reg_pointer (x, BITS_PER_UNIT);
579 else if (GET_CODE (x) == PLUS
580 && GET_CODE (XEXP (x, 0)) == REG
581 && GET_CODE (XEXP (x, 1)) == CONST_INT)
582 mark_reg_pointer (XEXP (x, 0), BITS_PER_UNIT);
584 /* OLDX may have been the address on a temporary. Update the address
585 to indicate that X is now used. */
586 update_temp_slot_address (oldx, x);
591 /* Like `memory_address' but pretend `flag_force_addr' is 0. */
594 memory_address_noforce (mode, x)
595 enum machine_mode mode;
598 int ambient_force_addr = flag_force_addr;
602 val = memory_address (mode, x);
603 flag_force_addr = ambient_force_addr;
607 /* Convert a mem ref into one with a valid memory address.
608 Pass through anything else unchanged. */
614 if (GET_CODE (ref) != MEM)
616 if (memory_address_p (GET_MODE (ref), XEXP (ref, 0)))
618 /* Don't alter REF itself, since that is probably a stack slot. */
619 return change_address (ref, GET_MODE (ref), XEXP (ref, 0));
622 /* Given REF, either a MEM or a REG, and T, either the type of X or
623 the expression corresponding to REF, set RTX_UNCHANGING_P if
627 maybe_set_unchanging (ref, t)
631 /* We can set RTX_UNCHANGING_P from TREE_READONLY for decls whose
632 initialization is only executed once, or whose initializer always
633 has the same value. Currently we simplify this to PARM_DECLs in the
634 first case, and decls with TREE_CONSTANT initializers in the second. */
635 if ((TREE_READONLY (t) && DECL_P (t)
636 && (TREE_CODE (t) == PARM_DECL
637 || DECL_INITIAL (t) == NULL_TREE
638 || TREE_CONSTANT (DECL_INITIAL (t))))
639 || TREE_CODE_CLASS (TREE_CODE (t)) == 'c')
640 RTX_UNCHANGING_P (ref) = 1;
643 /* Given REF, a MEM, and T, either the type of X or the expression
644 corresponding to REF, set the memory attributes. OBJECTP is nonzero
645 if we are making a new object of this type. */
648 set_mem_attributes (ref, t, objectp)
655 /* It can happen that type_for_mode was given a mode for which there
656 is no language-level type. In which case it returns NULL, which
661 type = TYPE_P (t) ? t : TREE_TYPE (t);
663 /* Get the alias set from the expression or type (perhaps using a
664 front-end routine) and then copy bits from the type. */
666 /* It is incorrect to set RTX_UNCHANGING_P from TREE_READONLY (type)
667 here, because, in C and C++, the fact that a location is accessed
668 through a const expression does not mean that the value there can
670 MEM_ALIAS_SET (ref) = get_alias_set (t);
671 MEM_VOLATILE_P (ref) = TYPE_VOLATILE (type);
672 MEM_IN_STRUCT_P (ref) = AGGREGATE_TYPE_P (type);
674 /* If we are making an object of this type, we know that it is a scalar if
675 the type is not an aggregate. */
676 if (objectp && ! AGGREGATE_TYPE_P (type))
677 MEM_SCALAR_P (ref) = 1;
679 /* If T is a type, this is all we can do. Otherwise, we may be able
680 to deduce some more information about the expression. */
684 maybe_set_unchanging (ref, t);
685 if (TREE_THIS_VOLATILE (t))
686 MEM_VOLATILE_P (ref) = 1;
688 /* Now see if we can say more about whether it's an aggregate or
689 scalar. If we already know it's an aggregate, don't bother. */
690 if (MEM_IN_STRUCT_P (ref))
693 /* Now remove any NOPs: they don't change what the underlying object is.
694 Likewise for SAVE_EXPR. */
695 while (TREE_CODE (t) == NOP_EXPR || TREE_CODE (t) == CONVERT_EXPR
696 || TREE_CODE (t) == NON_LVALUE_EXPR || TREE_CODE (t) == SAVE_EXPR)
697 t = TREE_OPERAND (t, 0);
699 /* Since we already know the type isn't an aggregate, if this is a decl,
700 it must be a scalar. Or if it is a reference into an aggregate,
701 this is part of an aggregate. Otherwise we don't know. */
703 MEM_SCALAR_P (ref) = 1;
704 else if (TREE_CODE (t) == COMPONENT_REF || TREE_CODE (t) == ARRAY_REF
705 || TREE_CODE (t) == ARRAY_RANGE_REF
706 || TREE_CODE (t) == BIT_FIELD_REF)
707 MEM_IN_STRUCT_P (ref) = 1;
710 /* Return a modified copy of X with its memory address copied
711 into a temporary register to protect it from side effects.
712 If X is not a MEM, it is returned unchanged (and not copied).
713 Perhaps even if it is a MEM, if there is no need to change it. */
721 if (GET_CODE (x) != MEM)
725 if (rtx_unstable_p (addr))
727 rtx temp = force_reg (Pmode, copy_all_regs (addr));
728 rtx mem = gen_rtx_MEM (GET_MODE (x), temp);
730 MEM_COPY_ATTRIBUTES (mem, x);
736 /* Copy the value or contents of X to a new temp reg and return that reg. */
742 register rtx temp = gen_reg_rtx (GET_MODE (x));
744 /* If not an operand, must be an address with PLUS and MULT so
745 do the computation. */
746 if (! general_operand (x, VOIDmode))
747 x = force_operand (x, temp);
750 emit_move_insn (temp, x);
755 /* Like copy_to_reg but always give the new register mode Pmode
756 in case X is a constant. */
762 return copy_to_mode_reg (Pmode, x);
765 /* Like copy_to_reg but always give the new register mode MODE
766 in case X is a constant. */
769 copy_to_mode_reg (mode, x)
770 enum machine_mode mode;
773 register rtx temp = gen_reg_rtx (mode);
775 /* If not an operand, must be an address with PLUS and MULT so
776 do the computation. */
777 if (! general_operand (x, VOIDmode))
778 x = force_operand (x, temp);
780 if (GET_MODE (x) != mode && GET_MODE (x) != VOIDmode)
783 emit_move_insn (temp, x);
787 /* Load X into a register if it is not already one.
788 Use mode MODE for the register.
789 X should be valid for mode MODE, but it may be a constant which
790 is valid for all integer modes; that's why caller must specify MODE.
792 The caller must not alter the value in the register we return,
793 since we mark it as a "constant" register. */
797 enum machine_mode mode;
800 register rtx temp, insn, set;
802 if (GET_CODE (x) == REG)
805 temp = gen_reg_rtx (mode);
807 if (! general_operand (x, mode))
808 x = force_operand (x, NULL_RTX);
810 insn = emit_move_insn (temp, x);
812 /* Let optimizers know that TEMP's value never changes
813 and that X can be substituted for it. Don't get confused
814 if INSN set something else (such as a SUBREG of TEMP). */
816 && (set = single_set (insn)) != 0
817 && SET_DEST (set) == temp)
819 rtx note = find_reg_note (insn, REG_EQUAL, NULL_RTX);
824 REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_EQUAL, x, REG_NOTES (insn));
829 /* If X is a memory ref, copy its contents to a new temp reg and return
830 that reg. Otherwise, return X. */
838 if (GET_CODE (x) != MEM || GET_MODE (x) == BLKmode)
841 temp = gen_reg_rtx (GET_MODE (x));
842 emit_move_insn (temp, x);
846 /* Copy X to TARGET (if it's nonzero and a reg)
847 or to a new temp reg and return that reg.
848 MODE is the mode to use for X in case it is a constant. */
851 copy_to_suggested_reg (x, target, mode)
853 enum machine_mode mode;
857 if (target && GET_CODE (target) == REG)
860 temp = gen_reg_rtx (mode);
862 emit_move_insn (temp, x);
866 /* Return the mode to use to store a scalar of TYPE and MODE.
867 PUNSIGNEDP points to the signedness of the type and may be adjusted
868 to show what signedness to use on extension operations.
870 FOR_CALL is non-zero if this call is promoting args for a call. */
873 promote_mode (type, mode, punsignedp, for_call)
875 enum machine_mode mode;
877 int for_call ATTRIBUTE_UNUSED;
879 enum tree_code code = TREE_CODE (type);
880 int unsignedp = *punsignedp;
882 #ifdef PROMOTE_FOR_CALL_ONLY
890 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
891 case CHAR_TYPE: case REAL_TYPE: case OFFSET_TYPE:
892 PROMOTE_MODE (mode, unsignedp, type);
896 #ifdef POINTERS_EXTEND_UNSIGNED
900 unsignedp = POINTERS_EXTEND_UNSIGNED;
908 *punsignedp = unsignedp;
912 /* Adjust the stack pointer by ADJUST (an rtx for a number of bytes).
913 This pops when ADJUST is positive. ADJUST need not be constant. */
916 adjust_stack (adjust)
920 adjust = protect_from_queue (adjust, 0);
922 if (adjust == const0_rtx)
925 /* We expect all variable sized adjustments to be multiple of
926 PREFERRED_STACK_BOUNDARY. */
927 if (GET_CODE (adjust) == CONST_INT)
928 stack_pointer_delta -= INTVAL (adjust);
930 temp = expand_binop (Pmode,
931 #ifdef STACK_GROWS_DOWNWARD
936 stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
939 if (temp != stack_pointer_rtx)
940 emit_move_insn (stack_pointer_rtx, temp);
943 /* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes).
944 This pushes when ADJUST is positive. ADJUST need not be constant. */
947 anti_adjust_stack (adjust)
951 adjust = protect_from_queue (adjust, 0);
953 if (adjust == const0_rtx)
956 /* We expect all variable sized adjustments to be multiple of
957 PREFERRED_STACK_BOUNDARY. */
958 if (GET_CODE (adjust) == CONST_INT)
959 stack_pointer_delta += INTVAL (adjust);
961 temp = expand_binop (Pmode,
962 #ifdef STACK_GROWS_DOWNWARD
967 stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
970 if (temp != stack_pointer_rtx)
971 emit_move_insn (stack_pointer_rtx, temp);
974 /* Round the size of a block to be pushed up to the boundary required
975 by this machine. SIZE is the desired size, which need not be constant. */
981 #ifdef PREFERRED_STACK_BOUNDARY
982 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
985 if (GET_CODE (size) == CONST_INT)
987 int new = (INTVAL (size) + align - 1) / align * align;
988 if (INTVAL (size) != new)
989 size = GEN_INT (new);
993 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
994 but we know it can't. So add ourselves and then do
996 size = expand_binop (Pmode, add_optab, size, GEN_INT (align - 1),
997 NULL_RTX, 1, OPTAB_LIB_WIDEN);
998 size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size, GEN_INT (align),
1000 size = expand_mult (Pmode, size, GEN_INT (align), NULL_RTX, 1);
1002 #endif /* PREFERRED_STACK_BOUNDARY */
1006 /* Save the stack pointer for the purpose in SAVE_LEVEL. PSAVE is a pointer
1007 to a previously-created save area. If no save area has been allocated,
1008 this function will allocate one. If a save area is specified, it
1009 must be of the proper mode.
1011 The insns are emitted after insn AFTER, if nonzero, otherwise the insns
1012 are emitted at the current position. */
1015 emit_stack_save (save_level, psave, after)
1016 enum save_level save_level;
1021 /* The default is that we use a move insn and save in a Pmode object. */
1022 rtx (*fcn) PARAMS ((rtx, rtx)) = gen_move_insn;
1023 enum machine_mode mode = STACK_SAVEAREA_MODE (save_level);
1025 /* See if this machine has anything special to do for this kind of save. */
1028 #ifdef HAVE_save_stack_block
1030 if (HAVE_save_stack_block)
1031 fcn = gen_save_stack_block;
1034 #ifdef HAVE_save_stack_function
1036 if (HAVE_save_stack_function)
1037 fcn = gen_save_stack_function;
1040 #ifdef HAVE_save_stack_nonlocal
1042 if (HAVE_save_stack_nonlocal)
1043 fcn = gen_save_stack_nonlocal;
1050 /* If there is no save area and we have to allocate one, do so. Otherwise
1051 verify the save area is the proper mode. */
1055 if (mode != VOIDmode)
1057 if (save_level == SAVE_NONLOCAL)
1058 *psave = sa = assign_stack_local (mode, GET_MODE_SIZE (mode), 0);
1060 *psave = sa = gen_reg_rtx (mode);
1065 if (mode == VOIDmode || GET_MODE (sa) != mode)
1074 /* We must validize inside the sequence, to ensure that any instructions
1075 created by the validize call also get moved to the right place. */
1077 sa = validize_mem (sa);
1078 emit_insn (fcn (sa, stack_pointer_rtx));
1079 seq = gen_sequence ();
1081 emit_insn_after (seq, after);
1086 sa = validize_mem (sa);
1087 emit_insn (fcn (sa, stack_pointer_rtx));
1091 /* Restore the stack pointer for the purpose in SAVE_LEVEL. SA is the save
1092 area made by emit_stack_save. If it is zero, we have nothing to do.
1094 Put any emitted insns after insn AFTER, if nonzero, otherwise at
1095 current position. */
1098 emit_stack_restore (save_level, sa, after)
1099 enum save_level save_level;
1103 /* The default is that we use a move insn. */
1104 rtx (*fcn) PARAMS ((rtx, rtx)) = gen_move_insn;
1106 /* See if this machine has anything special to do for this kind of save. */
1109 #ifdef HAVE_restore_stack_block
1111 if (HAVE_restore_stack_block)
1112 fcn = gen_restore_stack_block;
1115 #ifdef HAVE_restore_stack_function
1117 if (HAVE_restore_stack_function)
1118 fcn = gen_restore_stack_function;
1121 #ifdef HAVE_restore_stack_nonlocal
1123 if (HAVE_restore_stack_nonlocal)
1124 fcn = gen_restore_stack_nonlocal;
1132 sa = validize_mem (sa);
1139 emit_insn (fcn (stack_pointer_rtx, sa));
1140 seq = gen_sequence ();
1142 emit_insn_after (seq, after);
1145 emit_insn (fcn (stack_pointer_rtx, sa));
1148 #ifdef SETJMP_VIA_SAVE_AREA
1149 /* Optimize RTL generated by allocate_dynamic_stack_space for targets
1150 where SETJMP_VIA_SAVE_AREA is true. The problem is that on these
1151 platforms, the dynamic stack space used can corrupt the original
1152 frame, thus causing a crash if a longjmp unwinds to it. */
1155 optimize_save_area_alloca (insns)
1160 for (insn = insns; insn; insn = NEXT_INSN(insn))
1164 if (GET_CODE (insn) != INSN)
1167 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
1169 if (REG_NOTE_KIND (note) != REG_SAVE_AREA)
1172 if (!current_function_calls_setjmp)
1174 rtx pat = PATTERN (insn);
1176 /* If we do not see the note in a pattern matching
1177 these precise characteristics, we did something
1178 entirely wrong in allocate_dynamic_stack_space.
1180 Note, one way this could happen is if SETJMP_VIA_SAVE_AREA
1181 was defined on a machine where stacks grow towards higher
1184 Right now only supported port with stack that grow upward
1185 is the HPPA and it does not define SETJMP_VIA_SAVE_AREA. */
1186 if (GET_CODE (pat) != SET
1187 || SET_DEST (pat) != stack_pointer_rtx
1188 || GET_CODE (SET_SRC (pat)) != MINUS
1189 || XEXP (SET_SRC (pat), 0) != stack_pointer_rtx)
1192 /* This will now be transformed into a (set REG REG)
1193 so we can just blow away all the other notes. */
1194 XEXP (SET_SRC (pat), 1) = XEXP (note, 0);
1195 REG_NOTES (insn) = NULL_RTX;
1199 /* setjmp was called, we must remove the REG_SAVE_AREA
1200 note so that later passes do not get confused by its
1202 if (note == REG_NOTES (insn))
1204 REG_NOTES (insn) = XEXP (note, 1);
1210 for (srch = REG_NOTES (insn); srch; srch = XEXP (srch, 1))
1211 if (XEXP (srch, 1) == note)
1214 if (srch == NULL_RTX)
1217 XEXP (srch, 1) = XEXP (note, 1);
1220 /* Once we've seen the note of interest, we need not look at
1221 the rest of them. */
1226 #endif /* SETJMP_VIA_SAVE_AREA */
1228 /* Return an rtx representing the address of an area of memory dynamically
1229 pushed on the stack. This region of memory is always aligned to
1230 a multiple of BIGGEST_ALIGNMENT.
1232 Any required stack pointer alignment is preserved.
1234 SIZE is an rtx representing the size of the area.
1235 TARGET is a place in which the address can be placed.
1237 KNOWN_ALIGN is the alignment (in bits) that we know SIZE has. */
1240 allocate_dynamic_stack_space (size, target, known_align)
1245 #ifdef SETJMP_VIA_SAVE_AREA
1246 rtx setjmpless_size = NULL_RTX;
1249 /* If we're asking for zero bytes, it doesn't matter what we point
1250 to since we can't dereference it. But return a reasonable
1252 if (size == const0_rtx)
1253 return virtual_stack_dynamic_rtx;
1255 /* Otherwise, show we're calling alloca or equivalent. */
1256 current_function_calls_alloca = 1;
1258 /* Ensure the size is in the proper mode. */
1259 if (GET_MODE (size) != VOIDmode && GET_MODE (size) != Pmode)
1260 size = convert_to_mode (Pmode, size, 1);
1262 /* We can't attempt to minimize alignment necessary, because we don't
1263 know the final value of preferred_stack_boundary yet while executing
1265 #ifdef PREFERRED_STACK_BOUNDARY
1266 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
1269 /* We will need to ensure that the address we return is aligned to
1270 BIGGEST_ALIGNMENT. If STACK_DYNAMIC_OFFSET is defined, we don't
1271 always know its final value at this point in the compilation (it
1272 might depend on the size of the outgoing parameter lists, for
1273 example), so we must align the value to be returned in that case.
1274 (Note that STACK_DYNAMIC_OFFSET will have a default non-zero value if
1275 STACK_POINTER_OFFSET or ACCUMULATE_OUTGOING_ARGS are defined).
1276 We must also do an alignment operation on the returned value if
1277 the stack pointer alignment is less strict that BIGGEST_ALIGNMENT.
1279 If we have to align, we must leave space in SIZE for the hole
1280 that might result from the alignment operation. */
1282 #if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET) || ! defined (PREFERRED_STACK_BOUNDARY)
1283 #define MUST_ALIGN 1
1285 #define MUST_ALIGN (PREFERRED_STACK_BOUNDARY < BIGGEST_ALIGNMENT)
1290 = force_operand (plus_constant (size,
1291 BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1),
1294 #ifdef SETJMP_VIA_SAVE_AREA
1295 /* If setjmp restores regs from a save area in the stack frame,
1296 avoid clobbering the reg save area. Note that the offset of
1297 virtual_incoming_args_rtx includes the preallocated stack args space.
1298 It would be no problem to clobber that, but it's on the wrong side
1299 of the old save area. */
1302 = expand_binop (Pmode, sub_optab, virtual_stack_dynamic_rtx,
1303 stack_pointer_rtx, NULL_RTX, 1, OPTAB_LIB_WIDEN);
1305 if (!current_function_calls_setjmp)
1307 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
1309 /* See optimize_save_area_alloca to understand what is being
1312 #if !defined(PREFERRED_STACK_BOUNDARY) || !defined(MUST_ALIGN) || (PREFERRED_STACK_BOUNDARY != BIGGEST_ALIGNMENT)
1313 /* If anyone creates a target with these characteristics, let them
1314 know that our optimization cannot work correctly in such a case. */
1318 if (GET_CODE (size) == CONST_INT)
1320 HOST_WIDE_INT new = INTVAL (size) / align * align;
1322 if (INTVAL (size) != new)
1323 setjmpless_size = GEN_INT (new);
1325 setjmpless_size = size;
1329 /* Since we know overflow is not possible, we avoid using
1330 CEIL_DIV_EXPR and use TRUNC_DIV_EXPR instead. */
1331 setjmpless_size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size,
1332 GEN_INT (align), NULL_RTX, 1);
1333 setjmpless_size = expand_mult (Pmode, setjmpless_size,
1334 GEN_INT (align), NULL_RTX, 1);
1336 /* Our optimization works based upon being able to perform a simple
1337 transformation of this RTL into a (set REG REG) so make sure things
1338 did in fact end up in a REG. */
1339 if (!register_operand (setjmpless_size, Pmode))
1340 setjmpless_size = force_reg (Pmode, setjmpless_size);
1343 size = expand_binop (Pmode, add_optab, size, dynamic_offset,
1344 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1346 #endif /* SETJMP_VIA_SAVE_AREA */
1348 /* Round the size to a multiple of the required stack alignment.
1349 Since the stack if presumed to be rounded before this allocation,
1350 this will maintain the required alignment.
1352 If the stack grows downward, we could save an insn by subtracting
1353 SIZE from the stack pointer and then aligning the stack pointer.
1354 The problem with this is that the stack pointer may be unaligned
1355 between the execution of the subtraction and alignment insns and
1356 some machines do not allow this. Even on those that do, some
1357 signal handlers malfunction if a signal should occur between those
1358 insns. Since this is an extremely rare event, we have no reliable
1359 way of knowing which systems have this problem. So we avoid even
1360 momentarily mis-aligning the stack. */
1362 #ifdef PREFERRED_STACK_BOUNDARY
1363 /* If we added a variable amount to SIZE,
1364 we can no longer assume it is aligned. */
1365 #if !defined (SETJMP_VIA_SAVE_AREA)
1366 if (MUST_ALIGN || known_align % PREFERRED_STACK_BOUNDARY != 0)
1368 size = round_push (size);
1371 do_pending_stack_adjust ();
1373 /* We ought to be called always on the toplevel and stack ought to be aligned
1375 #ifdef PREFERRED_STACK_BOUNDARY
1376 if (stack_pointer_delta % (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT))
1380 /* If needed, check that we have the required amount of stack. Take into
1381 account what has already been checked. */
1382 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
1383 probe_stack_range (STACK_CHECK_MAX_FRAME_SIZE + STACK_CHECK_PROTECT, size);
1385 /* Don't use a TARGET that isn't a pseudo or is the wrong mode. */
1386 if (target == 0 || GET_CODE (target) != REG
1387 || REGNO (target) < FIRST_PSEUDO_REGISTER
1388 || GET_MODE (target) != Pmode)
1389 target = gen_reg_rtx (Pmode);
1391 mark_reg_pointer (target, known_align);
1393 /* Perform the required allocation from the stack. Some systems do
1394 this differently than simply incrementing/decrementing from the
1395 stack pointer, such as acquiring the space by calling malloc(). */
1396 #ifdef HAVE_allocate_stack
1397 if (HAVE_allocate_stack)
1399 enum machine_mode mode = STACK_SIZE_MODE;
1400 insn_operand_predicate_fn pred;
1402 pred = insn_data[(int) CODE_FOR_allocate_stack].operand[0].predicate;
1403 if (pred && ! ((*pred) (target, Pmode)))
1404 #ifdef POINTERS_EXTEND_UNSIGNED
1405 target = convert_memory_address (Pmode, target);
1407 target = copy_to_mode_reg (Pmode, target);
1410 if (mode == VOIDmode)
1413 pred = insn_data[(int) CODE_FOR_allocate_stack].operand[1].predicate;
1414 if (pred && ! ((*pred) (size, mode)))
1415 size = copy_to_mode_reg (mode, size);
1417 emit_insn (gen_allocate_stack (target, size));
1422 #ifndef STACK_GROWS_DOWNWARD
1423 emit_move_insn (target, virtual_stack_dynamic_rtx);
1426 /* Check stack bounds if necessary. */
1427 if (current_function_limit_stack)
1430 rtx space_available = gen_label_rtx ();
1431 #ifdef STACK_GROWS_DOWNWARD
1432 available = expand_binop (Pmode, sub_optab,
1433 stack_pointer_rtx, stack_limit_rtx,
1434 NULL_RTX, 1, OPTAB_WIDEN);
1436 available = expand_binop (Pmode, sub_optab,
1437 stack_limit_rtx, stack_pointer_rtx,
1438 NULL_RTX, 1, OPTAB_WIDEN);
1440 emit_cmp_and_jump_insns (available, size, GEU, NULL_RTX, Pmode, 1,
1441 0, space_available);
1444 emit_insn (gen_trap ());
1447 error ("stack limits not supported on this target");
1449 emit_label (space_available);
1452 anti_adjust_stack (size);
1453 #ifdef SETJMP_VIA_SAVE_AREA
1454 if (setjmpless_size != NULL_RTX)
1456 rtx note_target = get_last_insn ();
1458 REG_NOTES (note_target)
1459 = gen_rtx_EXPR_LIST (REG_SAVE_AREA, setjmpless_size,
1460 REG_NOTES (note_target));
1462 #endif /* SETJMP_VIA_SAVE_AREA */
1464 #ifdef STACK_GROWS_DOWNWARD
1465 emit_move_insn (target, virtual_stack_dynamic_rtx);
1471 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
1472 but we know it can't. So add ourselves and then do
1474 target = expand_binop (Pmode, add_optab, target,
1475 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1),
1476 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1477 target = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, target,
1478 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT),
1480 target = expand_mult (Pmode, target,
1481 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT),
1485 /* Some systems require a particular insn to refer to the stack
1486 to make the pages exist. */
1489 emit_insn (gen_probe ());
1492 /* Record the new stack level for nonlocal gotos. */
1493 if (nonlocal_goto_handler_slots != 0)
1494 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
1499 /* A front end may want to override GCC's stack checking by providing a
1500 run-time routine to call to check the stack, so provide a mechanism for
1501 calling that routine. */
1503 static rtx stack_check_libfunc;
1506 set_stack_check_libfunc (libfunc)
1509 stack_check_libfunc = libfunc;
1512 /* Emit one stack probe at ADDRESS, an address within the stack. */
1515 emit_stack_probe (address)
1518 rtx memref = gen_rtx_MEM (word_mode, address);
1520 MEM_VOLATILE_P (memref) = 1;
1522 if (STACK_CHECK_PROBE_LOAD)
1523 emit_move_insn (gen_reg_rtx (word_mode), memref);
1525 emit_move_insn (memref, const0_rtx);
1528 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
1529 FIRST is a constant and size is a Pmode RTX. These are offsets from the
1530 current stack pointer. STACK_GROWS_DOWNWARD says whether to add or
1531 subtract from the stack. If SIZE is constant, this is done
1532 with a fixed number of probes. Otherwise, we must make a loop. */
1534 #ifdef STACK_GROWS_DOWNWARD
1535 #define STACK_GROW_OP MINUS
1537 #define STACK_GROW_OP PLUS
1541 probe_stack_range (first, size)
1542 HOST_WIDE_INT first;
1545 /* First see if the front end has set up a function for us to call to
1547 if (stack_check_libfunc != 0)
1549 rtx addr = memory_address (QImode,
1550 gen_rtx (STACK_GROW_OP, Pmode,
1552 plus_constant (size, first)));
1554 #ifdef POINTERS_EXTEND_UNSIGNED
1555 if (GET_MODE (addr) != ptr_mode)
1556 addr = convert_memory_address (ptr_mode, addr);
1559 emit_library_call (stack_check_libfunc, 0, VOIDmode, 1, addr,
1563 /* Next see if we have an insn to check the stack. Use it if so. */
1564 #ifdef HAVE_check_stack
1565 else if (HAVE_check_stack)
1567 insn_operand_predicate_fn pred;
1569 = force_operand (gen_rtx_STACK_GROW_OP (Pmode,
1571 plus_constant (size, first)),
1574 pred = insn_data[(int) CODE_FOR_check_stack].operand[0].predicate;
1575 if (pred && ! ((*pred) (last_addr, Pmode)))
1576 last_addr = copy_to_mode_reg (Pmode, last_addr);
1578 emit_insn (gen_check_stack (last_addr));
1582 /* If we have to generate explicit probes, see if we have a constant
1583 small number of them to generate. If so, that's the easy case. */
1584 else if (GET_CODE (size) == CONST_INT
1585 && INTVAL (size) < 10 * STACK_CHECK_PROBE_INTERVAL)
1587 HOST_WIDE_INT offset;
1589 /* Start probing at FIRST + N * STACK_CHECK_PROBE_INTERVAL
1590 for values of N from 1 until it exceeds LAST. If only one
1591 probe is needed, this will not generate any code. Then probe
1593 for (offset = first + STACK_CHECK_PROBE_INTERVAL;
1594 offset < INTVAL (size);
1595 offset = offset + STACK_CHECK_PROBE_INTERVAL)
1596 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1600 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1602 plus_constant (size, first)));
1605 /* In the variable case, do the same as above, but in a loop. We emit loop
1606 notes so that loop optimization can be done. */
1610 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1612 GEN_INT (first + STACK_CHECK_PROBE_INTERVAL)),
1615 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1617 plus_constant (size, first)),
1619 rtx incr = GEN_INT (STACK_CHECK_PROBE_INTERVAL);
1620 rtx loop_lab = gen_label_rtx ();
1621 rtx test_lab = gen_label_rtx ();
1622 rtx end_lab = gen_label_rtx ();
1625 if (GET_CODE (test_addr) != REG
1626 || REGNO (test_addr) < FIRST_PSEUDO_REGISTER)
1627 test_addr = force_reg (Pmode, test_addr);
1629 emit_note (NULL, NOTE_INSN_LOOP_BEG);
1630 emit_jump (test_lab);
1632 emit_label (loop_lab);
1633 emit_stack_probe (test_addr);
1635 emit_note (NULL, NOTE_INSN_LOOP_CONT);
1637 #ifdef STACK_GROWS_DOWNWARD
1638 #define CMP_OPCODE GTU
1639 temp = expand_binop (Pmode, sub_optab, test_addr, incr, test_addr,
1642 #define CMP_OPCODE LTU
1643 temp = expand_binop (Pmode, add_optab, test_addr, incr, test_addr,
1647 if (temp != test_addr)
1650 emit_label (test_lab);
1651 emit_cmp_and_jump_insns (test_addr, last_addr, CMP_OPCODE,
1652 NULL_RTX, Pmode, 1, 0, loop_lab);
1653 emit_jump (end_lab);
1654 emit_note (NULL, NOTE_INSN_LOOP_END);
1655 emit_label (end_lab);
1657 emit_stack_probe (last_addr);
1661 /* Return an rtx representing the register or memory location
1662 in which a scalar value of data type VALTYPE
1663 was returned by a function call to function FUNC.
1664 FUNC is a FUNCTION_DECL node if the precise function is known,
1666 OUTGOING is 1 if on a machine with register windows this function
1667 should return the register in which the function will put its result
1671 hard_function_value (valtype, func, outgoing)
1673 tree func ATTRIBUTE_UNUSED;
1674 int outgoing ATTRIBUTE_UNUSED;
1678 #ifdef FUNCTION_OUTGOING_VALUE
1680 val = FUNCTION_OUTGOING_VALUE (valtype, func);
1683 val = FUNCTION_VALUE (valtype, func);
1685 if (GET_CODE (val) == REG
1686 && GET_MODE (val) == BLKmode)
1688 unsigned HOST_WIDE_INT bytes = int_size_in_bytes (valtype);
1689 enum machine_mode tmpmode;
1691 for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
1692 tmpmode != VOIDmode;
1693 tmpmode = GET_MODE_WIDER_MODE (tmpmode))
1695 /* Have we found a large enough mode? */
1696 if (GET_MODE_SIZE (tmpmode) >= bytes)
1700 /* No suitable mode found. */
1701 if (tmpmode == VOIDmode)
1704 PUT_MODE (val, tmpmode);
1709 /* Return an rtx representing the register or memory location
1710 in which a scalar value of mode MODE was returned by a library call. */
1713 hard_libcall_value (mode)
1714 enum machine_mode mode;
1716 return LIBCALL_VALUE (mode);
1719 /* Look up the tree code for a given rtx code
1720 to provide the arithmetic operation for REAL_ARITHMETIC.
1721 The function returns an int because the caller may not know
1722 what `enum tree_code' means. */
1725 rtx_to_tree_code (code)
1728 enum tree_code tcode;
1751 tcode = LAST_AND_UNUSED_TREE_CODE;
1754 return ((int) tcode);