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;
82 register enum machine_mode mode;
96 return GEN_INT (INTVAL (x) + c);
100 unsigned HOST_WIDE_INT l1 = CONST_DOUBLE_LOW (x);
101 HOST_WIDE_INT h1 = CONST_DOUBLE_HIGH (x);
102 unsigned HOST_WIDE_INT l2 = c;
103 HOST_WIDE_INT h2 = c < 0 ? ~0 : 0;
104 unsigned HOST_WIDE_INT lv;
107 add_double (l1, h1, l2, h2, &lv, &hv);
109 return immed_double_const (lv, hv, VOIDmode);
113 /* If this is a reference to the constant pool, try replacing it with
114 a reference to a new constant. If the resulting address isn't
115 valid, don't return it because we have no way to validize it. */
116 if (GET_CODE (XEXP (x, 0)) == SYMBOL_REF
117 && CONSTANT_POOL_ADDRESS_P (XEXP (x, 0)))
120 = force_const_mem (GET_MODE (x),
121 plus_constant (get_pool_constant (XEXP (x, 0)),
123 if (memory_address_p (GET_MODE (tem), XEXP (tem, 0)))
129 /* If adding to something entirely constant, set a flag
130 so that we can add a CONST around the result. */
141 /* The interesting case is adding the integer to a sum.
142 Look for constant term in the sum and combine
143 with C. For an integer constant term, we make a combined
144 integer. For a constant term that is not an explicit integer,
145 we cannot really combine, but group them together anyway.
147 Restart or use a recursive call in case the remaining operand is
148 something that we handle specially, such as a SYMBOL_REF.
150 We may not immediately return from the recursive call here, lest
151 all_constant gets lost. */
153 if (GET_CODE (XEXP (x, 1)) == CONST_INT)
155 c += INTVAL (XEXP (x, 1));
157 if (GET_MODE (x) != VOIDmode)
158 c = trunc_int_for_mode (c, GET_MODE (x));
163 else if (CONSTANT_P (XEXP (x, 1)))
165 x = gen_rtx_PLUS (mode, XEXP (x, 0), plus_constant (XEXP (x, 1), c));
168 else if (find_constant_term_loc (&y))
170 /* We need to be careful since X may be shared and we can't
171 modify it in place. */
172 rtx copy = copy_rtx (x);
173 rtx *const_loc = find_constant_term_loc (©);
175 *const_loc = plus_constant (*const_loc, c);
182 return gen_rtx_LO_SUM (mode, XEXP (x, 0),
183 plus_constant (XEXP (x, 1), c));
191 x = gen_rtx_PLUS (mode, x, GEN_INT (c));
193 if (GET_CODE (x) == SYMBOL_REF || GET_CODE (x) == LABEL_REF)
195 else if (all_constant)
196 return gen_rtx_CONST (mode, x);
201 /* If X is a sum, return a new sum like X but lacking any constant terms.
202 Add all the removed constant terms into *CONSTPTR.
203 X itself is not altered. The result != X if and only if
204 it is not isomorphic to X. */
207 eliminate_constant_term (x, constptr)
214 if (GET_CODE (x) != PLUS)
217 /* First handle constants appearing at this level explicitly. */
218 if (GET_CODE (XEXP (x, 1)) == CONST_INT
219 && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x), *constptr,
221 && GET_CODE (tem) == CONST_INT)
224 return eliminate_constant_term (XEXP (x, 0), constptr);
228 x0 = eliminate_constant_term (XEXP (x, 0), &tem);
229 x1 = eliminate_constant_term (XEXP (x, 1), &tem);
230 if ((x1 != XEXP (x, 1) || x0 != XEXP (x, 0))
231 && 0 != (tem = simplify_binary_operation (PLUS, GET_MODE (x),
233 && GET_CODE (tem) == CONST_INT)
236 return gen_rtx_PLUS (GET_MODE (x), x0, x1);
242 /* Returns the insn that next references REG after INSN, or 0
243 if REG is clobbered before next referenced or we cannot find
244 an insn that references REG in a straight-line piece of code. */
247 find_next_ref (reg, insn)
253 for (insn = NEXT_INSN (insn); insn; insn = next)
255 next = NEXT_INSN (insn);
256 if (GET_CODE (insn) == NOTE)
258 if (GET_CODE (insn) == CODE_LABEL
259 || GET_CODE (insn) == BARRIER)
261 if (GET_CODE (insn) == INSN
262 || GET_CODE (insn) == JUMP_INSN
263 || GET_CODE (insn) == CALL_INSN)
265 if (reg_set_p (reg, insn))
267 if (reg_mentioned_p (reg, PATTERN (insn)))
269 if (GET_CODE (insn) == JUMP_INSN)
271 if (any_uncondjump_p (insn))
272 next = JUMP_LABEL (insn);
276 if (GET_CODE (insn) == CALL_INSN
277 && REGNO (reg) < FIRST_PSEUDO_REGISTER
278 && call_used_regs[REGNO (reg)])
287 /* Return an rtx for the size in bytes of the value of EXP. */
295 if (TREE_CODE_CLASS (TREE_CODE (exp)) == 'd'
296 && DECL_SIZE_UNIT (exp) != 0)
297 size = DECL_SIZE_UNIT (exp);
299 size = size_in_bytes (TREE_TYPE (exp));
301 if (TREE_CODE (size) != INTEGER_CST
302 && contains_placeholder_p (size))
303 size = build (WITH_RECORD_EXPR, sizetype, size, exp);
305 return expand_expr (size, NULL_RTX, TYPE_MODE (sizetype),
306 EXPAND_MEMORY_USE_BAD);
309 /* Return a copy of X in which all memory references
310 and all constants that involve symbol refs
311 have been replaced with new temporary registers.
312 Also emit code to load the memory locations and constants
313 into those registers.
315 If X contains no such constants or memory references,
316 X itself (not a copy) is returned.
318 If a constant is found in the address that is not a legitimate constant
319 in an insn, it is left alone in the hope that it might be valid in the
322 X may contain no arithmetic except addition, subtraction and multiplication.
323 Values returned by expand_expr with 1 for sum_ok fit this constraint. */
326 break_out_memory_refs (x)
329 if (GET_CODE (x) == MEM
330 || (CONSTANT_P (x) && CONSTANT_ADDRESS_P (x)
331 && GET_MODE (x) != VOIDmode))
332 x = force_reg (GET_MODE (x), x);
333 else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS
334 || GET_CODE (x) == MULT)
336 register rtx op0 = break_out_memory_refs (XEXP (x, 0));
337 register rtx op1 = break_out_memory_refs (XEXP (x, 1));
339 if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1))
340 x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1);
346 #ifdef POINTERS_EXTEND_UNSIGNED
348 /* Given X, a memory address in ptr_mode, convert it to an address
349 in Pmode, or vice versa (TO_MODE says which way). We take advantage of
350 the fact that pointers are not allowed to overflow by commuting arithmetic
351 operations over conversions so that address arithmetic insns can be
355 convert_memory_address (to_mode, x)
356 enum machine_mode to_mode;
359 enum machine_mode from_mode = to_mode == ptr_mode ? Pmode : ptr_mode;
362 /* Here we handle some special cases. If none of them apply, fall through
363 to the default case. */
364 switch (GET_CODE (x))
371 if (GET_MODE (SUBREG_REG (x)) == to_mode)
372 return SUBREG_REG (x);
376 temp = gen_rtx_LABEL_REF (to_mode, XEXP (x, 0));
377 LABEL_REF_NONLOCAL_P (temp) = LABEL_REF_NONLOCAL_P (x);
381 temp = gen_rtx_SYMBOL_REF (to_mode, XSTR (x, 0));
382 SYMBOL_REF_FLAG (temp) = SYMBOL_REF_FLAG (x);
383 CONSTANT_POOL_ADDRESS_P (temp) = CONSTANT_POOL_ADDRESS_P (x);
384 STRING_POOL_ADDRESS_P (temp) = STRING_POOL_ADDRESS_P (x);
388 return gen_rtx_CONST (to_mode,
389 convert_memory_address (to_mode, XEXP (x, 0)));
393 /* For addition the second operand is a small constant, we can safely
394 permute the conversion and addition operation. We can always safely
395 permute them if we are making the address narrower. In addition,
396 always permute the operations if this is a constant. */
397 if (GET_MODE_SIZE (to_mode) < GET_MODE_SIZE (from_mode)
398 || (GET_CODE (x) == PLUS && GET_CODE (XEXP (x, 1)) == CONST_INT
399 && (INTVAL (XEXP (x, 1)) + 20000 < 40000
400 || CONSTANT_P (XEXP (x, 0)))))
401 return gen_rtx_fmt_ee (GET_CODE (x), to_mode,
402 convert_memory_address (to_mode, XEXP (x, 0)),
403 convert_memory_address (to_mode, XEXP (x, 1)));
410 return convert_modes (to_mode, from_mode,
411 x, POINTERS_EXTEND_UNSIGNED);
415 /* Given a memory address or facsimile X, construct a new address,
416 currently equivalent, that is stable: future stores won't change it.
418 X must be composed of constants, register and memory references
419 combined with addition, subtraction and multiplication:
420 in other words, just what you can get from expand_expr if sum_ok is 1.
422 Works by making copies of all regs and memory locations used
423 by X and combining them the same way X does.
424 You could also stabilize the reference to this address
425 by copying the address to a register with copy_to_reg;
426 but then you wouldn't get indexed addressing in the reference. */
432 if (GET_CODE (x) == REG)
434 if (REGNO (x) != FRAME_POINTER_REGNUM
435 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
436 && REGNO (x) != HARD_FRAME_POINTER_REGNUM
441 else if (GET_CODE (x) == MEM)
443 else if (GET_CODE (x) == PLUS || GET_CODE (x) == MINUS
444 || GET_CODE (x) == MULT)
446 register rtx op0 = copy_all_regs (XEXP (x, 0));
447 register rtx op1 = copy_all_regs (XEXP (x, 1));
448 if (op0 != XEXP (x, 0) || op1 != XEXP (x, 1))
449 x = gen_rtx_fmt_ee (GET_CODE (x), Pmode, op0, op1);
454 /* Return something equivalent to X but valid as a memory address
455 for something of mode MODE. When X is not itself valid, this
456 works by copying X or subexpressions of it into registers. */
459 memory_address (mode, x)
460 enum machine_mode mode;
463 register rtx oldx = x;
465 if (GET_CODE (x) == ADDRESSOF)
468 #ifdef POINTERS_EXTEND_UNSIGNED
469 if (GET_MODE (x) == ptr_mode)
470 x = convert_memory_address (Pmode, x);
473 /* By passing constant addresses thru registers
474 we get a chance to cse them. */
475 if (! cse_not_expected && CONSTANT_P (x) && CONSTANT_ADDRESS_P (x))
476 x = force_reg (Pmode, x);
478 /* Accept a QUEUED that refers to a REG
479 even though that isn't a valid address.
480 On attempting to put this in an insn we will call protect_from_queue
481 which will turn it into a REG, which is valid. */
482 else if (GET_CODE (x) == QUEUED
483 && GET_CODE (QUEUED_VAR (x)) == REG)
486 /* We get better cse by rejecting indirect addressing at this stage.
487 Let the combiner create indirect addresses where appropriate.
488 For now, generate the code so that the subexpressions useful to share
489 are visible. But not if cse won't be done! */
492 if (! cse_not_expected && GET_CODE (x) != REG)
493 x = break_out_memory_refs (x);
495 /* At this point, any valid address is accepted. */
496 GO_IF_LEGITIMATE_ADDRESS (mode, x, win);
498 /* If it was valid before but breaking out memory refs invalidated it,
499 use it the old way. */
500 if (memory_address_p (mode, oldx))
503 /* Perform machine-dependent transformations on X
504 in certain cases. This is not necessary since the code
505 below can handle all possible cases, but machine-dependent
506 transformations can make better code. */
507 LEGITIMIZE_ADDRESS (x, oldx, mode, win);
509 /* PLUS and MULT can appear in special ways
510 as the result of attempts to make an address usable for indexing.
511 Usually they are dealt with by calling force_operand, below.
512 But a sum containing constant terms is special
513 if removing them makes the sum a valid address:
514 then we generate that address in a register
515 and index off of it. We do this because it often makes
516 shorter code, and because the addresses thus generated
517 in registers often become common subexpressions. */
518 if (GET_CODE (x) == PLUS)
520 rtx constant_term = const0_rtx;
521 rtx y = eliminate_constant_term (x, &constant_term);
522 if (constant_term == const0_rtx
523 || ! memory_address_p (mode, y))
524 x = force_operand (x, NULL_RTX);
527 y = gen_rtx_PLUS (GET_MODE (x), copy_to_reg (y), constant_term);
528 if (! memory_address_p (mode, y))
529 x = force_operand (x, NULL_RTX);
535 else if (GET_CODE (x) == MULT || GET_CODE (x) == MINUS)
536 x = force_operand (x, NULL_RTX);
538 /* If we have a register that's an invalid address,
539 it must be a hard reg of the wrong class. Copy it to a pseudo. */
540 else if (GET_CODE (x) == REG)
543 /* Last resort: copy the value to a register, since
544 the register is a valid address. */
546 x = force_reg (Pmode, x);
553 if (flag_force_addr && ! cse_not_expected && GET_CODE (x) != REG
554 /* Don't copy an addr via a reg if it is one of our stack slots. */
555 && ! (GET_CODE (x) == PLUS
556 && (XEXP (x, 0) == virtual_stack_vars_rtx
557 || XEXP (x, 0) == virtual_incoming_args_rtx)))
559 if (general_operand (x, Pmode))
560 x = force_reg (Pmode, x);
562 x = force_operand (x, NULL_RTX);
568 /* If we didn't change the address, we are done. Otherwise, mark
569 a reg as a pointer if we have REG or REG + CONST_INT. */
572 else if (GET_CODE (x) == REG)
573 mark_reg_pointer (x, BITS_PER_UNIT);
574 else if (GET_CODE (x) == PLUS
575 && GET_CODE (XEXP (x, 0)) == REG
576 && GET_CODE (XEXP (x, 1)) == CONST_INT)
577 mark_reg_pointer (XEXP (x, 0), BITS_PER_UNIT);
579 /* OLDX may have been the address on a temporary. Update the address
580 to indicate that X is now used. */
581 update_temp_slot_address (oldx, x);
586 /* Like `memory_address' but pretend `flag_force_addr' is 0. */
589 memory_address_noforce (mode, x)
590 enum machine_mode mode;
593 int ambient_force_addr = flag_force_addr;
597 val = memory_address (mode, x);
598 flag_force_addr = ambient_force_addr;
602 /* Convert a mem ref into one with a valid memory address.
603 Pass through anything else unchanged. */
609 if (GET_CODE (ref) != MEM)
611 if (memory_address_p (GET_MODE (ref), XEXP (ref, 0)))
613 /* Don't alter REF itself, since that is probably a stack slot. */
614 return change_address (ref, GET_MODE (ref), XEXP (ref, 0));
617 /* Given REF, either a MEM or a REG, and T, either the type of X or
618 the expression corresponding to REF, set RTX_UNCHANGING_P if
622 maybe_set_unchanging (ref, t)
626 /* We can set RTX_UNCHANGING_P from TREE_READONLY for decls whose
627 initialization is only executed once, or whose initializer always
628 has the same value. Currently we simplify this to PARM_DECLs in the
629 first case, and decls with TREE_CONSTANT initializers in the second. */
630 if ((TREE_READONLY (t) && DECL_P (t)
631 && (TREE_CODE (t) == PARM_DECL
632 || DECL_INITIAL (t) == NULL_TREE
633 || TREE_CONSTANT (DECL_INITIAL (t))))
634 || TREE_CODE_CLASS (TREE_CODE (t)) == 'c')
635 RTX_UNCHANGING_P (ref) = 1;
638 /* Given REF, a MEM, and T, either the type of X or the expression
639 corresponding to REF, set the memory attributes. OBJECTP is nonzero
640 if we are making a new object of this type. */
643 set_mem_attributes (ref, t, objectp)
650 /* It can happen that type_for_mode was given a mode for which there
651 is no language-level type. In which case it returns NULL, which
656 type = TYPE_P (t) ? t : TREE_TYPE (t);
658 /* Get the alias set from the expression or type (perhaps using a
659 front-end routine) and then copy bits from the type. */
661 /* It is incorrect to set RTX_UNCHANGING_P from TREE_READONLY (type)
662 here, because, in C and C++, the fact that a location is accessed
663 through a const expression does not mean that the value there can
665 MEM_ALIAS_SET (ref) = get_alias_set (t);
666 MEM_VOLATILE_P (ref) = TYPE_VOLATILE (type);
667 MEM_IN_STRUCT_P (ref) = AGGREGATE_TYPE_P (type);
669 /* If we are making an object of this type, we know that it is a scalar if
670 the type is not an aggregate. */
671 if (objectp && ! AGGREGATE_TYPE_P (type))
672 MEM_SCALAR_P (ref) = 1;
674 /* If T is a type, this is all we can do. Otherwise, we may be able
675 to deduce some more information about the expression. */
679 maybe_set_unchanging (ref, t);
680 if (TREE_THIS_VOLATILE (t))
681 MEM_VOLATILE_P (ref) = 1;
683 /* Now see if we can say more about whether it's an aggregate or
684 scalar. If we already know it's an aggregate, don't bother. */
685 if (MEM_IN_STRUCT_P (ref))
688 /* Now remove any NOPs: they don't change what the underlying object is.
689 Likewise for SAVE_EXPR. */
690 while (TREE_CODE (t) == NOP_EXPR || TREE_CODE (t) == CONVERT_EXPR
691 || TREE_CODE (t) == NON_LVALUE_EXPR || TREE_CODE (t) == SAVE_EXPR)
692 t = TREE_OPERAND (t, 0);
694 /* Since we already know the type isn't an aggregate, if this is a decl,
695 it must be a scalar. Or if it is a reference into an aggregate,
696 this is part of an aggregate. Otherwise we don't know. */
698 MEM_SCALAR_P (ref) = 1;
699 else if (TREE_CODE (t) == COMPONENT_REF || TREE_CODE (t) == ARRAY_REF
700 || TREE_CODE (t) == ARRAY_RANGE_REF
701 || TREE_CODE (t) == BIT_FIELD_REF)
702 MEM_IN_STRUCT_P (ref) = 1;
705 /* Return a modified copy of X with its memory address copied
706 into a temporary register to protect it from side effects.
707 If X is not a MEM, it is returned unchanged (and not copied).
708 Perhaps even if it is a MEM, if there is no need to change it. */
716 if (GET_CODE (x) != MEM)
720 if (rtx_unstable_p (addr))
722 rtx temp = force_reg (Pmode, copy_all_regs (addr));
723 rtx mem = gen_rtx_MEM (GET_MODE (x), temp);
725 MEM_COPY_ATTRIBUTES (mem, x);
731 /* Copy the value or contents of X to a new temp reg and return that reg. */
737 register rtx temp = gen_reg_rtx (GET_MODE (x));
739 /* If not an operand, must be an address with PLUS and MULT so
740 do the computation. */
741 if (! general_operand (x, VOIDmode))
742 x = force_operand (x, temp);
745 emit_move_insn (temp, x);
750 /* Like copy_to_reg but always give the new register mode Pmode
751 in case X is a constant. */
757 return copy_to_mode_reg (Pmode, x);
760 /* Like copy_to_reg but always give the new register mode MODE
761 in case X is a constant. */
764 copy_to_mode_reg (mode, x)
765 enum machine_mode mode;
768 register rtx temp = gen_reg_rtx (mode);
770 /* If not an operand, must be an address with PLUS and MULT so
771 do the computation. */
772 if (! general_operand (x, VOIDmode))
773 x = force_operand (x, temp);
775 if (GET_MODE (x) != mode && GET_MODE (x) != VOIDmode)
778 emit_move_insn (temp, x);
782 /* Load X into a register if it is not already one.
783 Use mode MODE for the register.
784 X should be valid for mode MODE, but it may be a constant which
785 is valid for all integer modes; that's why caller must specify MODE.
787 The caller must not alter the value in the register we return,
788 since we mark it as a "constant" register. */
792 enum machine_mode mode;
795 register rtx temp, insn, set;
797 if (GET_CODE (x) == REG)
800 temp = gen_reg_rtx (mode);
802 if (! general_operand (x, mode))
803 x = force_operand (x, NULL_RTX);
805 insn = emit_move_insn (temp, x);
807 /* Let optimizers know that TEMP's value never changes
808 and that X can be substituted for it. Don't get confused
809 if INSN set something else (such as a SUBREG of TEMP). */
811 && (set = single_set (insn)) != 0
812 && SET_DEST (set) == temp)
814 rtx note = find_reg_note (insn, REG_EQUAL, NULL_RTX);
819 REG_NOTES (insn) = gen_rtx_EXPR_LIST (REG_EQUAL, x, REG_NOTES (insn));
824 /* If X is a memory ref, copy its contents to a new temp reg and return
825 that reg. Otherwise, return X. */
833 if (GET_CODE (x) != MEM || GET_MODE (x) == BLKmode)
836 temp = gen_reg_rtx (GET_MODE (x));
837 emit_move_insn (temp, x);
841 /* Copy X to TARGET (if it's nonzero and a reg)
842 or to a new temp reg and return that reg.
843 MODE is the mode to use for X in case it is a constant. */
846 copy_to_suggested_reg (x, target, mode)
848 enum machine_mode mode;
852 if (target && GET_CODE (target) == REG)
855 temp = gen_reg_rtx (mode);
857 emit_move_insn (temp, x);
861 /* Return the mode to use to store a scalar of TYPE and MODE.
862 PUNSIGNEDP points to the signedness of the type and may be adjusted
863 to show what signedness to use on extension operations.
865 FOR_CALL is non-zero if this call is promoting args for a call. */
868 promote_mode (type, mode, punsignedp, for_call)
870 enum machine_mode mode;
872 int for_call ATTRIBUTE_UNUSED;
874 enum tree_code code = TREE_CODE (type);
875 int unsignedp = *punsignedp;
877 #ifdef PROMOTE_FOR_CALL_ONLY
885 case INTEGER_TYPE: case ENUMERAL_TYPE: case BOOLEAN_TYPE:
886 case CHAR_TYPE: case REAL_TYPE: case OFFSET_TYPE:
887 PROMOTE_MODE (mode, unsignedp, type);
891 #ifdef POINTERS_EXTEND_UNSIGNED
895 unsignedp = POINTERS_EXTEND_UNSIGNED;
903 *punsignedp = unsignedp;
907 /* Adjust the stack pointer by ADJUST (an rtx for a number of bytes).
908 This pops when ADJUST is positive. ADJUST need not be constant. */
911 adjust_stack (adjust)
915 adjust = protect_from_queue (adjust, 0);
917 if (adjust == const0_rtx)
920 /* We expect all variable sized adjustments to be multiple of
921 PREFERRED_STACK_BOUNDARY. */
922 if (GET_CODE (adjust) == CONST_INT)
923 stack_pointer_delta -= INTVAL (adjust);
925 temp = expand_binop (Pmode,
926 #ifdef STACK_GROWS_DOWNWARD
931 stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
934 if (temp != stack_pointer_rtx)
935 emit_move_insn (stack_pointer_rtx, temp);
938 /* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes).
939 This pushes when ADJUST is positive. ADJUST need not be constant. */
942 anti_adjust_stack (adjust)
946 adjust = protect_from_queue (adjust, 0);
948 if (adjust == const0_rtx)
951 /* We expect all variable sized adjustments to be multiple of
952 PREFERRED_STACK_BOUNDARY. */
953 if (GET_CODE (adjust) == CONST_INT)
954 stack_pointer_delta += INTVAL (adjust);
956 temp = expand_binop (Pmode,
957 #ifdef STACK_GROWS_DOWNWARD
962 stack_pointer_rtx, adjust, stack_pointer_rtx, 0,
965 if (temp != stack_pointer_rtx)
966 emit_move_insn (stack_pointer_rtx, temp);
969 /* Round the size of a block to be pushed up to the boundary required
970 by this machine. SIZE is the desired size, which need not be constant. */
976 #ifdef PREFERRED_STACK_BOUNDARY
977 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
980 if (GET_CODE (size) == CONST_INT)
982 int new = (INTVAL (size) + align - 1) / align * align;
983 if (INTVAL (size) != new)
984 size = GEN_INT (new);
988 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
989 but we know it can't. So add ourselves and then do
991 size = expand_binop (Pmode, add_optab, size, GEN_INT (align - 1),
992 NULL_RTX, 1, OPTAB_LIB_WIDEN);
993 size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size, GEN_INT (align),
995 size = expand_mult (Pmode, size, GEN_INT (align), NULL_RTX, 1);
997 #endif /* PREFERRED_STACK_BOUNDARY */
1001 /* Save the stack pointer for the purpose in SAVE_LEVEL. PSAVE is a pointer
1002 to a previously-created save area. If no save area has been allocated,
1003 this function will allocate one. If a save area is specified, it
1004 must be of the proper mode.
1006 The insns are emitted after insn AFTER, if nonzero, otherwise the insns
1007 are emitted at the current position. */
1010 emit_stack_save (save_level, psave, after)
1011 enum save_level save_level;
1016 /* The default is that we use a move insn and save in a Pmode object. */
1017 rtx (*fcn) PARAMS ((rtx, rtx)) = gen_move_insn;
1018 enum machine_mode mode = STACK_SAVEAREA_MODE (save_level);
1020 /* See if this machine has anything special to do for this kind of save. */
1023 #ifdef HAVE_save_stack_block
1025 if (HAVE_save_stack_block)
1026 fcn = gen_save_stack_block;
1029 #ifdef HAVE_save_stack_function
1031 if (HAVE_save_stack_function)
1032 fcn = gen_save_stack_function;
1035 #ifdef HAVE_save_stack_nonlocal
1037 if (HAVE_save_stack_nonlocal)
1038 fcn = gen_save_stack_nonlocal;
1045 /* If there is no save area and we have to allocate one, do so. Otherwise
1046 verify the save area is the proper mode. */
1050 if (mode != VOIDmode)
1052 if (save_level == SAVE_NONLOCAL)
1053 *psave = sa = assign_stack_local (mode, GET_MODE_SIZE (mode), 0);
1055 *psave = sa = gen_reg_rtx (mode);
1060 if (mode == VOIDmode || GET_MODE (sa) != mode)
1069 /* We must validize inside the sequence, to ensure that any instructions
1070 created by the validize call also get moved to the right place. */
1072 sa = validize_mem (sa);
1073 emit_insn (fcn (sa, stack_pointer_rtx));
1074 seq = gen_sequence ();
1076 emit_insn_after (seq, after);
1081 sa = validize_mem (sa);
1082 emit_insn (fcn (sa, stack_pointer_rtx));
1086 /* Restore the stack pointer for the purpose in SAVE_LEVEL. SA is the save
1087 area made by emit_stack_save. If it is zero, we have nothing to do.
1089 Put any emitted insns after insn AFTER, if nonzero, otherwise at
1090 current position. */
1093 emit_stack_restore (save_level, sa, after)
1094 enum save_level save_level;
1098 /* The default is that we use a move insn. */
1099 rtx (*fcn) PARAMS ((rtx, rtx)) = gen_move_insn;
1101 /* See if this machine has anything special to do for this kind of save. */
1104 #ifdef HAVE_restore_stack_block
1106 if (HAVE_restore_stack_block)
1107 fcn = gen_restore_stack_block;
1110 #ifdef HAVE_restore_stack_function
1112 if (HAVE_restore_stack_function)
1113 fcn = gen_restore_stack_function;
1116 #ifdef HAVE_restore_stack_nonlocal
1118 if (HAVE_restore_stack_nonlocal)
1119 fcn = gen_restore_stack_nonlocal;
1127 sa = validize_mem (sa);
1134 emit_insn (fcn (stack_pointer_rtx, sa));
1135 seq = gen_sequence ();
1137 emit_insn_after (seq, after);
1140 emit_insn (fcn (stack_pointer_rtx, sa));
1143 #ifdef SETJMP_VIA_SAVE_AREA
1144 /* Optimize RTL generated by allocate_dynamic_stack_space for targets
1145 where SETJMP_VIA_SAVE_AREA is true. The problem is that on these
1146 platforms, the dynamic stack space used can corrupt the original
1147 frame, thus causing a crash if a longjmp unwinds to it. */
1150 optimize_save_area_alloca (insns)
1155 for (insn = insns; insn; insn = NEXT_INSN(insn))
1159 if (GET_CODE (insn) != INSN)
1162 for (note = REG_NOTES (insn); note; note = XEXP (note, 1))
1164 if (REG_NOTE_KIND (note) != REG_SAVE_AREA)
1167 if (!current_function_calls_setjmp)
1169 rtx pat = PATTERN (insn);
1171 /* If we do not see the note in a pattern matching
1172 these precise characteristics, we did something
1173 entirely wrong in allocate_dynamic_stack_space.
1175 Note, one way this could happen is if SETJMP_VIA_SAVE_AREA
1176 was defined on a machine where stacks grow towards higher
1179 Right now only supported port with stack that grow upward
1180 is the HPPA and it does not define SETJMP_VIA_SAVE_AREA. */
1181 if (GET_CODE (pat) != SET
1182 || SET_DEST (pat) != stack_pointer_rtx
1183 || GET_CODE (SET_SRC (pat)) != MINUS
1184 || XEXP (SET_SRC (pat), 0) != stack_pointer_rtx)
1187 /* This will now be transformed into a (set REG REG)
1188 so we can just blow away all the other notes. */
1189 XEXP (SET_SRC (pat), 1) = XEXP (note, 0);
1190 REG_NOTES (insn) = NULL_RTX;
1194 /* setjmp was called, we must remove the REG_SAVE_AREA
1195 note so that later passes do not get confused by its
1197 if (note == REG_NOTES (insn))
1199 REG_NOTES (insn) = XEXP (note, 1);
1205 for (srch = REG_NOTES (insn); srch; srch = XEXP (srch, 1))
1206 if (XEXP (srch, 1) == note)
1209 if (srch == NULL_RTX)
1212 XEXP (srch, 1) = XEXP (note, 1);
1215 /* Once we've seen the note of interest, we need not look at
1216 the rest of them. */
1221 #endif /* SETJMP_VIA_SAVE_AREA */
1223 /* Return an rtx representing the address of an area of memory dynamically
1224 pushed on the stack. This region of memory is always aligned to
1225 a multiple of BIGGEST_ALIGNMENT.
1227 Any required stack pointer alignment is preserved.
1229 SIZE is an rtx representing the size of the area.
1230 TARGET is a place in which the address can be placed.
1232 KNOWN_ALIGN is the alignment (in bits) that we know SIZE has. */
1235 allocate_dynamic_stack_space (size, target, known_align)
1240 #ifdef SETJMP_VIA_SAVE_AREA
1241 rtx setjmpless_size = NULL_RTX;
1244 /* If we're asking for zero bytes, it doesn't matter what we point
1245 to since we can't dereference it. But return a reasonable
1247 if (size == const0_rtx)
1248 return virtual_stack_dynamic_rtx;
1250 /* Otherwise, show we're calling alloca or equivalent. */
1251 current_function_calls_alloca = 1;
1253 /* Ensure the size is in the proper mode. */
1254 if (GET_MODE (size) != VOIDmode && GET_MODE (size) != Pmode)
1255 size = convert_to_mode (Pmode, size, 1);
1257 /* We can't attempt to minimize alignment necessary, because we don't
1258 know the final value of preferred_stack_boundary yet while executing
1260 #ifdef PREFERRED_STACK_BOUNDARY
1261 cfun->preferred_stack_boundary = PREFERRED_STACK_BOUNDARY;
1264 /* We will need to ensure that the address we return is aligned to
1265 BIGGEST_ALIGNMENT. If STACK_DYNAMIC_OFFSET is defined, we don't
1266 always know its final value at this point in the compilation (it
1267 might depend on the size of the outgoing parameter lists, for
1268 example), so we must align the value to be returned in that case.
1269 (Note that STACK_DYNAMIC_OFFSET will have a default non-zero value if
1270 STACK_POINTER_OFFSET or ACCUMULATE_OUTGOING_ARGS are defined).
1271 We must also do an alignment operation on the returned value if
1272 the stack pointer alignment is less strict that BIGGEST_ALIGNMENT.
1274 If we have to align, we must leave space in SIZE for the hole
1275 that might result from the alignment operation. */
1277 #if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET) || ! defined (PREFERRED_STACK_BOUNDARY)
1278 #define MUST_ALIGN 1
1280 #define MUST_ALIGN (PREFERRED_STACK_BOUNDARY < BIGGEST_ALIGNMENT)
1285 = force_operand (plus_constant (size,
1286 BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1),
1289 #ifdef SETJMP_VIA_SAVE_AREA
1290 /* If setjmp restores regs from a save area in the stack frame,
1291 avoid clobbering the reg save area. Note that the offset of
1292 virtual_incoming_args_rtx includes the preallocated stack args space.
1293 It would be no problem to clobber that, but it's on the wrong side
1294 of the old save area. */
1297 = expand_binop (Pmode, sub_optab, virtual_stack_dynamic_rtx,
1298 stack_pointer_rtx, NULL_RTX, 1, OPTAB_LIB_WIDEN);
1300 if (!current_function_calls_setjmp)
1302 int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT;
1304 /* See optimize_save_area_alloca to understand what is being
1307 #if !defined(PREFERRED_STACK_BOUNDARY) || !defined(MUST_ALIGN) || (PREFERRED_STACK_BOUNDARY != BIGGEST_ALIGNMENT)
1308 /* If anyone creates a target with these characteristics, let them
1309 know that our optimization cannot work correctly in such a case. */
1313 if (GET_CODE (size) == CONST_INT)
1315 HOST_WIDE_INT new = INTVAL (size) / align * align;
1317 if (INTVAL (size) != new)
1318 setjmpless_size = GEN_INT (new);
1320 setjmpless_size = size;
1324 /* Since we know overflow is not possible, we avoid using
1325 CEIL_DIV_EXPR and use TRUNC_DIV_EXPR instead. */
1326 setjmpless_size = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, size,
1327 GEN_INT (align), NULL_RTX, 1);
1328 setjmpless_size = expand_mult (Pmode, setjmpless_size,
1329 GEN_INT (align), NULL_RTX, 1);
1331 /* Our optimization works based upon being able to perform a simple
1332 transformation of this RTL into a (set REG REG) so make sure things
1333 did in fact end up in a REG. */
1334 if (!register_operand (setjmpless_size, Pmode))
1335 setjmpless_size = force_reg (Pmode, setjmpless_size);
1338 size = expand_binop (Pmode, add_optab, size, dynamic_offset,
1339 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1341 #endif /* SETJMP_VIA_SAVE_AREA */
1343 /* Round the size to a multiple of the required stack alignment.
1344 Since the stack if presumed to be rounded before this allocation,
1345 this will maintain the required alignment.
1347 If the stack grows downward, we could save an insn by subtracting
1348 SIZE from the stack pointer and then aligning the stack pointer.
1349 The problem with this is that the stack pointer may be unaligned
1350 between the execution of the subtraction and alignment insns and
1351 some machines do not allow this. Even on those that do, some
1352 signal handlers malfunction if a signal should occur between those
1353 insns. Since this is an extremely rare event, we have no reliable
1354 way of knowing which systems have this problem. So we avoid even
1355 momentarily mis-aligning the stack. */
1357 #ifdef PREFERRED_STACK_BOUNDARY
1358 /* If we added a variable amount to SIZE,
1359 we can no longer assume it is aligned. */
1360 #if !defined (SETJMP_VIA_SAVE_AREA)
1361 if (MUST_ALIGN || known_align % PREFERRED_STACK_BOUNDARY != 0)
1363 size = round_push (size);
1366 do_pending_stack_adjust ();
1368 /* We ought to be called always on the toplevel and stack ought to be aligned
1370 #ifdef PREFERRED_STACK_BOUNDARY
1371 if (stack_pointer_delta % (PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT))
1375 /* If needed, check that we have the required amount of stack. Take into
1376 account what has already been checked. */
1377 if (flag_stack_check && ! STACK_CHECK_BUILTIN)
1378 probe_stack_range (STACK_CHECK_MAX_FRAME_SIZE + STACK_CHECK_PROTECT, size);
1380 /* Don't use a TARGET that isn't a pseudo or is the wrong mode. */
1381 if (target == 0 || GET_CODE (target) != REG
1382 || REGNO (target) < FIRST_PSEUDO_REGISTER
1383 || GET_MODE (target) != Pmode)
1384 target = gen_reg_rtx (Pmode);
1386 mark_reg_pointer (target, known_align);
1388 /* Perform the required allocation from the stack. Some systems do
1389 this differently than simply incrementing/decrementing from the
1390 stack pointer, such as acquiring the space by calling malloc(). */
1391 #ifdef HAVE_allocate_stack
1392 if (HAVE_allocate_stack)
1394 enum machine_mode mode = STACK_SIZE_MODE;
1395 insn_operand_predicate_fn pred;
1397 pred = insn_data[(int) CODE_FOR_allocate_stack].operand[0].predicate;
1398 if (pred && ! ((*pred) (target, Pmode)))
1399 #ifdef POINTERS_EXTEND_UNSIGNED
1400 target = convert_memory_address (Pmode, target);
1402 target = copy_to_mode_reg (Pmode, target);
1405 if (mode == VOIDmode)
1408 pred = insn_data[(int) CODE_FOR_allocate_stack].operand[1].predicate;
1409 if (pred && ! ((*pred) (size, mode)))
1410 size = copy_to_mode_reg (mode, size);
1412 emit_insn (gen_allocate_stack (target, size));
1417 #ifndef STACK_GROWS_DOWNWARD
1418 emit_move_insn (target, virtual_stack_dynamic_rtx);
1421 /* Check stack bounds if necessary. */
1422 if (current_function_limit_stack)
1425 rtx space_available = gen_label_rtx ();
1426 #ifdef STACK_GROWS_DOWNWARD
1427 available = expand_binop (Pmode, sub_optab,
1428 stack_pointer_rtx, stack_limit_rtx,
1429 NULL_RTX, 1, OPTAB_WIDEN);
1431 available = expand_binop (Pmode, sub_optab,
1432 stack_limit_rtx, stack_pointer_rtx,
1433 NULL_RTX, 1, OPTAB_WIDEN);
1435 emit_cmp_and_jump_insns (available, size, GEU, NULL_RTX, Pmode, 1,
1436 0, space_available);
1439 emit_insn (gen_trap ());
1442 error ("stack limits not supported on this target");
1444 emit_label (space_available);
1447 anti_adjust_stack (size);
1448 #ifdef SETJMP_VIA_SAVE_AREA
1449 if (setjmpless_size != NULL_RTX)
1451 rtx note_target = get_last_insn ();
1453 REG_NOTES (note_target)
1454 = gen_rtx_EXPR_LIST (REG_SAVE_AREA, setjmpless_size,
1455 REG_NOTES (note_target));
1457 #endif /* SETJMP_VIA_SAVE_AREA */
1459 #ifdef STACK_GROWS_DOWNWARD
1460 emit_move_insn (target, virtual_stack_dynamic_rtx);
1466 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
1467 but we know it can't. So add ourselves and then do
1469 target = expand_binop (Pmode, add_optab, target,
1470 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT - 1),
1471 NULL_RTX, 1, OPTAB_LIB_WIDEN);
1472 target = expand_divmod (0, TRUNC_DIV_EXPR, Pmode, target,
1473 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT),
1475 target = expand_mult (Pmode, target,
1476 GEN_INT (BIGGEST_ALIGNMENT / BITS_PER_UNIT),
1480 /* Some systems require a particular insn to refer to the stack
1481 to make the pages exist. */
1484 emit_insn (gen_probe ());
1487 /* Record the new stack level for nonlocal gotos. */
1488 if (nonlocal_goto_handler_slots != 0)
1489 emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, NULL_RTX);
1494 /* A front end may want to override GCC's stack checking by providing a
1495 run-time routine to call to check the stack, so provide a mechanism for
1496 calling that routine. */
1498 static rtx stack_check_libfunc;
1501 set_stack_check_libfunc (libfunc)
1504 stack_check_libfunc = libfunc;
1507 /* Emit one stack probe at ADDRESS, an address within the stack. */
1510 emit_stack_probe (address)
1513 rtx memref = gen_rtx_MEM (word_mode, address);
1515 MEM_VOLATILE_P (memref) = 1;
1517 if (STACK_CHECK_PROBE_LOAD)
1518 emit_move_insn (gen_reg_rtx (word_mode), memref);
1520 emit_move_insn (memref, const0_rtx);
1523 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
1524 FIRST is a constant and size is a Pmode RTX. These are offsets from the
1525 current stack pointer. STACK_GROWS_DOWNWARD says whether to add or
1526 subtract from the stack. If SIZE is constant, this is done
1527 with a fixed number of probes. Otherwise, we must make a loop. */
1529 #ifdef STACK_GROWS_DOWNWARD
1530 #define STACK_GROW_OP MINUS
1532 #define STACK_GROW_OP PLUS
1536 probe_stack_range (first, size)
1537 HOST_WIDE_INT first;
1540 /* First see if the front end has set up a function for us to call to
1542 if (stack_check_libfunc != 0)
1544 rtx addr = memory_address (QImode,
1545 gen_rtx (STACK_GROW_OP, Pmode,
1547 plus_constant (size, first)));
1549 #ifdef POINTERS_EXTEND_UNSIGNED
1550 if (GET_MODE (addr) != ptr_mode)
1551 addr = convert_memory_address (ptr_mode, addr);
1554 emit_library_call (stack_check_libfunc, 0, VOIDmode, 1, addr,
1558 /* Next see if we have an insn to check the stack. Use it if so. */
1559 #ifdef HAVE_check_stack
1560 else if (HAVE_check_stack)
1562 insn_operand_predicate_fn pred;
1564 = force_operand (gen_rtx_STACK_GROW_OP (Pmode,
1566 plus_constant (size, first)),
1569 pred = insn_data[(int) CODE_FOR_check_stack].operand[0].predicate;
1570 if (pred && ! ((*pred) (last_addr, Pmode)))
1571 last_addr = copy_to_mode_reg (Pmode, last_addr);
1573 emit_insn (gen_check_stack (last_addr));
1577 /* If we have to generate explicit probes, see if we have a constant
1578 small number of them to generate. If so, that's the easy case. */
1579 else if (GET_CODE (size) == CONST_INT
1580 && INTVAL (size) < 10 * STACK_CHECK_PROBE_INTERVAL)
1582 HOST_WIDE_INT offset;
1584 /* Start probing at FIRST + N * STACK_CHECK_PROBE_INTERVAL
1585 for values of N from 1 until it exceeds LAST. If only one
1586 probe is needed, this will not generate any code. Then probe
1588 for (offset = first + STACK_CHECK_PROBE_INTERVAL;
1589 offset < INTVAL (size);
1590 offset = offset + STACK_CHECK_PROBE_INTERVAL)
1591 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1595 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1597 plus_constant (size, first)));
1600 /* In the variable case, do the same as above, but in a loop. We emit loop
1601 notes so that loop optimization can be done. */
1605 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1607 GEN_INT (first + STACK_CHECK_PROBE_INTERVAL)),
1610 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP, Pmode,
1612 plus_constant (size, first)),
1614 rtx incr = GEN_INT (STACK_CHECK_PROBE_INTERVAL);
1615 rtx loop_lab = gen_label_rtx ();
1616 rtx test_lab = gen_label_rtx ();
1617 rtx end_lab = gen_label_rtx ();
1620 if (GET_CODE (test_addr) != REG
1621 || REGNO (test_addr) < FIRST_PSEUDO_REGISTER)
1622 test_addr = force_reg (Pmode, test_addr);
1624 emit_note (NULL, NOTE_INSN_LOOP_BEG);
1625 emit_jump (test_lab);
1627 emit_label (loop_lab);
1628 emit_stack_probe (test_addr);
1630 emit_note (NULL, NOTE_INSN_LOOP_CONT);
1632 #ifdef STACK_GROWS_DOWNWARD
1633 #define CMP_OPCODE GTU
1634 temp = expand_binop (Pmode, sub_optab, test_addr, incr, test_addr,
1637 #define CMP_OPCODE LTU
1638 temp = expand_binop (Pmode, add_optab, test_addr, incr, test_addr,
1642 if (temp != test_addr)
1645 emit_label (test_lab);
1646 emit_cmp_and_jump_insns (test_addr, last_addr, CMP_OPCODE,
1647 NULL_RTX, Pmode, 1, 0, loop_lab);
1648 emit_jump (end_lab);
1649 emit_note (NULL, NOTE_INSN_LOOP_END);
1650 emit_label (end_lab);
1652 emit_stack_probe (last_addr);
1656 /* Return an rtx representing the register or memory location
1657 in which a scalar value of data type VALTYPE
1658 was returned by a function call to function FUNC.
1659 FUNC is a FUNCTION_DECL node if the precise function is known,
1661 OUTGOING is 1 if on a machine with register windows this function
1662 should return the register in which the function will put its result
1666 hard_function_value (valtype, func, outgoing)
1668 tree func ATTRIBUTE_UNUSED;
1669 int outgoing ATTRIBUTE_UNUSED;
1673 #ifdef FUNCTION_OUTGOING_VALUE
1675 val = FUNCTION_OUTGOING_VALUE (valtype, func);
1678 val = FUNCTION_VALUE (valtype, func);
1680 if (GET_CODE (val) == REG
1681 && GET_MODE (val) == BLKmode)
1683 unsigned HOST_WIDE_INT bytes = int_size_in_bytes (valtype);
1684 enum machine_mode tmpmode;
1686 for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT);
1687 tmpmode != VOIDmode;
1688 tmpmode = GET_MODE_WIDER_MODE (tmpmode))
1690 /* Have we found a large enough mode? */
1691 if (GET_MODE_SIZE (tmpmode) >= bytes)
1695 /* No suitable mode found. */
1696 if (tmpmode == VOIDmode)
1699 PUT_MODE (val, tmpmode);
1704 /* Return an rtx representing the register or memory location
1705 in which a scalar value of mode MODE was returned by a library call. */
1708 hard_libcall_value (mode)
1709 enum machine_mode mode;
1711 return LIBCALL_VALUE (mode);
1714 /* Look up the tree code for a given rtx code
1715 to provide the arithmetic operation for REAL_ARITHMETIC.
1716 The function returns an int because the caller may not know
1717 what `enum tree_code' means. */
1720 rtx_to_tree_code (code)
1723 enum tree_code tcode;
1746 tcode = LAST_AND_UNUSED_TREE_CODE;
1749 return ((int) tcode);