1 /* Subroutines for manipulating rtx's in semantically interesting ways.
2 Copyright (C) 1987, 1991, 1994, 1995, 1996, 1997, 1998,
3 1999, 2000, 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it under
8 the terms of the GNU General Public License as published by the Free
9 Software Foundation; either version 2, or (at your option) any later
12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
13 WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING. If not, write to the Free
19 Software Foundation, 59 Temple Place - Suite 330, Boston, MA
25 #include "coretypes.h"
35 #include "hard-reg-set.h"
36 #include "insn-config.h"
39 #include "langhooks.h"
41 static rtx
break_out_memory_refs (rtx
);
42 static void emit_stack_probe (rtx
);
45 /* Truncate and perhaps sign-extend C as appropriate for MODE. */
48 trunc_int_for_mode (HOST_WIDE_INT c
, enum machine_mode mode
)
50 int width
= GET_MODE_BITSIZE (mode
);
52 /* You want to truncate to a _what_? */
53 if (! SCALAR_INT_MODE_P (mode
))
56 /* Canonicalize BImode to 0 and STORE_FLAG_VALUE. */
58 return c
& 1 ? STORE_FLAG_VALUE
: 0;
60 /* Sign-extend for the requested mode. */
62 if (width
< HOST_BITS_PER_WIDE_INT
)
64 HOST_WIDE_INT sign
= 1;
74 /* Return an rtx for the sum of X and the integer C.
76 This function should be used via the `plus_constant' macro. */
79 plus_constant_wide (rtx x
, HOST_WIDE_INT c
)
83 enum machine_mode mode
;
99 return GEN_INT (INTVAL (x
) + c
);
103 unsigned HOST_WIDE_INT l1
= CONST_DOUBLE_LOW (x
);
104 HOST_WIDE_INT h1
= CONST_DOUBLE_HIGH (x
);
105 unsigned HOST_WIDE_INT l2
= c
;
106 HOST_WIDE_INT h2
= c
< 0 ? ~0 : 0;
107 unsigned HOST_WIDE_INT lv
;
110 add_double (l1
, h1
, l2
, h2
, &lv
, &hv
);
112 return immed_double_const (lv
, hv
, VOIDmode
);
116 /* If this is a reference to the constant pool, try replacing it with
117 a reference to a new constant. If the resulting address isn't
118 valid, don't return it because we have no way to validize it. */
119 if (GET_CODE (XEXP (x
, 0)) == SYMBOL_REF
120 && CONSTANT_POOL_ADDRESS_P (XEXP (x
, 0)))
123 = force_const_mem (GET_MODE (x
),
124 plus_constant (get_pool_constant (XEXP (x
, 0)),
126 if (memory_address_p (GET_MODE (tem
), XEXP (tem
, 0)))
132 /* If adding to something entirely constant, set a flag
133 so that we can add a CONST around the result. */
144 /* The interesting case is adding the integer to a sum.
145 Look for constant term in the sum and combine
146 with C. For an integer constant term, we make a combined
147 integer. For a constant term that is not an explicit integer,
148 we cannot really combine, but group them together anyway.
150 Restart or use a recursive call in case the remaining operand is
151 something that we handle specially, such as a SYMBOL_REF.
153 We may not immediately return from the recursive call here, lest
154 all_constant gets lost. */
156 if (GET_CODE (XEXP (x
, 1)) == CONST_INT
)
158 c
+= INTVAL (XEXP (x
, 1));
160 if (GET_MODE (x
) != VOIDmode
)
161 c
= trunc_int_for_mode (c
, GET_MODE (x
));
166 else if (CONSTANT_P (XEXP (x
, 1)))
168 x
= gen_rtx_PLUS (mode
, XEXP (x
, 0), plus_constant (XEXP (x
, 1), c
));
171 else if (find_constant_term_loc (&y
))
173 /* We need to be careful since X may be shared and we can't
174 modify it in place. */
175 rtx copy
= copy_rtx (x
);
176 rtx
*const_loc
= find_constant_term_loc (©
);
178 *const_loc
= plus_constant (*const_loc
, c
);
189 x
= gen_rtx_PLUS (mode
, x
, GEN_INT (c
));
191 if (GET_CODE (x
) == SYMBOL_REF
|| GET_CODE (x
) == LABEL_REF
)
193 else if (all_constant
)
194 return gen_rtx_CONST (mode
, x
);
199 /* If X is a sum, return a new sum like X but lacking any constant terms.
200 Add all the removed constant terms into *CONSTPTR.
201 X itself is not altered. The result != X if and only if
202 it is not isomorphic to X. */
205 eliminate_constant_term (rtx x
, rtx
*constptr
)
210 if (GET_CODE (x
) != PLUS
)
213 /* First handle constants appearing at this level explicitly. */
214 if (GET_CODE (XEXP (x
, 1)) == CONST_INT
215 && 0 != (tem
= simplify_binary_operation (PLUS
, GET_MODE (x
), *constptr
,
217 && GET_CODE (tem
) == CONST_INT
)
220 return eliminate_constant_term (XEXP (x
, 0), constptr
);
224 x0
= eliminate_constant_term (XEXP (x
, 0), &tem
);
225 x1
= eliminate_constant_term (XEXP (x
, 1), &tem
);
226 if ((x1
!= XEXP (x
, 1) || x0
!= XEXP (x
, 0))
227 && 0 != (tem
= simplify_binary_operation (PLUS
, GET_MODE (x
),
229 && GET_CODE (tem
) == CONST_INT
)
232 return gen_rtx_PLUS (GET_MODE (x
), x0
, x1
);
238 /* Return an rtx for the size in bytes of the value of EXP. */
243 tree size
= lang_hooks
.expr_size (exp
);
245 if (CONTAINS_PLACEHOLDER_P (size
))
246 size
= build (WITH_RECORD_EXPR
, sizetype
, size
, exp
);
248 return expand_expr (size
, NULL_RTX
, TYPE_MODE (sizetype
), 0);
251 /* Return a wide integer for the size in bytes of the value of EXP, or -1
252 if the size can vary or is larger than an integer. */
255 int_expr_size (tree exp
)
257 tree t
= lang_hooks
.expr_size (exp
);
260 || TREE_CODE (t
) != INTEGER_CST
262 || TREE_INT_CST_HIGH (t
) != 0
263 /* If the result would appear negative, it's too big to represent. */
264 || (HOST_WIDE_INT
) TREE_INT_CST_LOW (t
) < 0)
267 return TREE_INT_CST_LOW (t
);
270 /* Return a copy of X in which all memory references
271 and all constants that involve symbol refs
272 have been replaced with new temporary registers.
273 Also emit code to load the memory locations and constants
274 into those registers.
276 If X contains no such constants or memory references,
277 X itself (not a copy) is returned.
279 If a constant is found in the address that is not a legitimate constant
280 in an insn, it is left alone in the hope that it might be valid in the
283 X may contain no arithmetic except addition, subtraction and multiplication.
284 Values returned by expand_expr with 1 for sum_ok fit this constraint. */
287 break_out_memory_refs (rtx x
)
289 if (GET_CODE (x
) == MEM
290 || (CONSTANT_P (x
) && CONSTANT_ADDRESS_P (x
)
291 && GET_MODE (x
) != VOIDmode
))
292 x
= force_reg (GET_MODE (x
), x
);
293 else if (GET_CODE (x
) == PLUS
|| GET_CODE (x
) == MINUS
294 || GET_CODE (x
) == MULT
)
296 rtx op0
= break_out_memory_refs (XEXP (x
, 0));
297 rtx op1
= break_out_memory_refs (XEXP (x
, 1));
299 if (op0
!= XEXP (x
, 0) || op1
!= XEXP (x
, 1))
300 x
= gen_rtx_fmt_ee (GET_CODE (x
), Pmode
, op0
, op1
);
306 /* Given X, a memory address in ptr_mode, convert it to an address
307 in Pmode, or vice versa (TO_MODE says which way). We take advantage of
308 the fact that pointers are not allowed to overflow by commuting arithmetic
309 operations over conversions so that address arithmetic insns can be
313 convert_memory_address (enum machine_mode to_mode ATTRIBUTE_UNUSED
,
316 #ifndef POINTERS_EXTEND_UNSIGNED
318 #else /* defined(POINTERS_EXTEND_UNSIGNED) */
319 enum machine_mode from_mode
;
323 /* If X already has the right mode, just return it. */
324 if (GET_MODE (x
) == to_mode
)
327 from_mode
= to_mode
== ptr_mode
? Pmode
: ptr_mode
;
329 /* Here we handle some special cases. If none of them apply, fall through
330 to the default case. */
331 switch (GET_CODE (x
))
335 if (GET_MODE_SIZE (to_mode
) < GET_MODE_SIZE (from_mode
))
337 else if (POINTERS_EXTEND_UNSIGNED
< 0)
339 else if (POINTERS_EXTEND_UNSIGNED
> 0)
343 temp
= simplify_unary_operation (code
, to_mode
, x
, from_mode
);
349 if ((SUBREG_PROMOTED_VAR_P (x
) || REG_POINTER (SUBREG_REG (x
)))
350 && GET_MODE (SUBREG_REG (x
)) == to_mode
)
351 return SUBREG_REG (x
);
355 temp
= gen_rtx_LABEL_REF (to_mode
, XEXP (x
, 0));
356 LABEL_REF_NONLOCAL_P (temp
) = LABEL_REF_NONLOCAL_P (x
);
361 temp
= shallow_copy_rtx (x
);
362 PUT_MODE (temp
, to_mode
);
367 return gen_rtx_CONST (to_mode
,
368 convert_memory_address (to_mode
, XEXP (x
, 0)));
373 /* For addition we can safely permute the conversion and addition
374 operation if one operand is a constant and converting the constant
375 does not change it. We can always safely permute them if we are
376 making the address narrower. */
377 if (GET_MODE_SIZE (to_mode
) < GET_MODE_SIZE (from_mode
)
378 || (GET_CODE (x
) == PLUS
379 && GET_CODE (XEXP (x
, 1)) == CONST_INT
380 && XEXP (x
, 1) == convert_memory_address (to_mode
, XEXP (x
, 1))))
381 return gen_rtx_fmt_ee (GET_CODE (x
), to_mode
,
382 convert_memory_address (to_mode
, XEXP (x
, 0)),
390 return convert_modes (to_mode
, from_mode
,
391 x
, POINTERS_EXTEND_UNSIGNED
);
392 #endif /* defined(POINTERS_EXTEND_UNSIGNED) */
395 /* Given a memory address or facsimile X, construct a new address,
396 currently equivalent, that is stable: future stores won't change it.
398 X must be composed of constants, register and memory references
399 combined with addition, subtraction and multiplication:
400 in other words, just what you can get from expand_expr if sum_ok is 1.
402 Works by making copies of all regs and memory locations used
403 by X and combining them the same way X does.
404 You could also stabilize the reference to this address
405 by copying the address to a register with copy_to_reg;
406 but then you wouldn't get indexed addressing in the reference. */
409 copy_all_regs (rtx x
)
411 if (GET_CODE (x
) == REG
)
413 if (REGNO (x
) != FRAME_POINTER_REGNUM
414 #if HARD_FRAME_POINTER_REGNUM != FRAME_POINTER_REGNUM
415 && REGNO (x
) != HARD_FRAME_POINTER_REGNUM
420 else if (GET_CODE (x
) == MEM
)
422 else if (GET_CODE (x
) == PLUS
|| GET_CODE (x
) == MINUS
423 || GET_CODE (x
) == MULT
)
425 rtx op0
= copy_all_regs (XEXP (x
, 0));
426 rtx op1
= copy_all_regs (XEXP (x
, 1));
427 if (op0
!= XEXP (x
, 0) || op1
!= XEXP (x
, 1))
428 x
= gen_rtx_fmt_ee (GET_CODE (x
), Pmode
, op0
, op1
);
433 /* Return something equivalent to X but valid as a memory address
434 for something of mode MODE. When X is not itself valid, this
435 works by copying X or subexpressions of it into registers. */
438 memory_address (enum machine_mode mode
, rtx x
)
442 if (GET_CODE (x
) == ADDRESSOF
)
445 x
= convert_memory_address (Pmode
, x
);
447 /* By passing constant addresses through registers
448 we get a chance to cse them. */
449 if (! cse_not_expected
&& CONSTANT_P (x
) && CONSTANT_ADDRESS_P (x
))
450 x
= force_reg (Pmode
, x
);
452 /* Accept a QUEUED that refers to a REG
453 even though that isn't a valid address.
454 On attempting to put this in an insn we will call protect_from_queue
455 which will turn it into a REG, which is valid. */
456 else if (GET_CODE (x
) == QUEUED
457 && GET_CODE (QUEUED_VAR (x
)) == REG
)
460 /* We get better cse by rejecting indirect addressing at this stage.
461 Let the combiner create indirect addresses where appropriate.
462 For now, generate the code so that the subexpressions useful to share
463 are visible. But not if cse won't be done! */
466 if (! cse_not_expected
&& GET_CODE (x
) != REG
)
467 x
= break_out_memory_refs (x
);
469 /* At this point, any valid address is accepted. */
470 GO_IF_LEGITIMATE_ADDRESS (mode
, x
, win
);
472 /* If it was valid before but breaking out memory refs invalidated it,
473 use it the old way. */
474 if (memory_address_p (mode
, oldx
))
477 /* Perform machine-dependent transformations on X
478 in certain cases. This is not necessary since the code
479 below can handle all possible cases, but machine-dependent
480 transformations can make better code. */
481 LEGITIMIZE_ADDRESS (x
, oldx
, mode
, win
);
483 /* PLUS and MULT can appear in special ways
484 as the result of attempts to make an address usable for indexing.
485 Usually they are dealt with by calling force_operand, below.
486 But a sum containing constant terms is special
487 if removing them makes the sum a valid address:
488 then we generate that address in a register
489 and index off of it. We do this because it often makes
490 shorter code, and because the addresses thus generated
491 in registers often become common subexpressions. */
492 if (GET_CODE (x
) == PLUS
)
494 rtx constant_term
= const0_rtx
;
495 rtx y
= eliminate_constant_term (x
, &constant_term
);
496 if (constant_term
== const0_rtx
497 || ! memory_address_p (mode
, y
))
498 x
= force_operand (x
, NULL_RTX
);
501 y
= gen_rtx_PLUS (GET_MODE (x
), copy_to_reg (y
), constant_term
);
502 if (! memory_address_p (mode
, y
))
503 x
= force_operand (x
, NULL_RTX
);
509 else if (GET_CODE (x
) == MULT
|| GET_CODE (x
) == MINUS
)
510 x
= force_operand (x
, NULL_RTX
);
512 /* If we have a register that's an invalid address,
513 it must be a hard reg of the wrong class. Copy it to a pseudo. */
514 else if (GET_CODE (x
) == REG
)
517 /* Last resort: copy the value to a register, since
518 the register is a valid address. */
520 x
= force_reg (Pmode
, x
);
527 if (flag_force_addr
&& ! cse_not_expected
&& GET_CODE (x
) != REG
528 /* Don't copy an addr via a reg if it is one of our stack slots. */
529 && ! (GET_CODE (x
) == PLUS
530 && (XEXP (x
, 0) == virtual_stack_vars_rtx
531 || XEXP (x
, 0) == virtual_incoming_args_rtx
)))
533 if (general_operand (x
, Pmode
))
534 x
= force_reg (Pmode
, x
);
536 x
= force_operand (x
, NULL_RTX
);
542 /* If we didn't change the address, we are done. Otherwise, mark
543 a reg as a pointer if we have REG or REG + CONST_INT. */
546 else if (GET_CODE (x
) == REG
)
547 mark_reg_pointer (x
, BITS_PER_UNIT
);
548 else if (GET_CODE (x
) == PLUS
549 && GET_CODE (XEXP (x
, 0)) == REG
550 && GET_CODE (XEXP (x
, 1)) == CONST_INT
)
551 mark_reg_pointer (XEXP (x
, 0), BITS_PER_UNIT
);
553 /* OLDX may have been the address on a temporary. Update the address
554 to indicate that X is now used. */
555 update_temp_slot_address (oldx
, x
);
560 /* Like `memory_address' but pretend `flag_force_addr' is 0. */
563 memory_address_noforce (enum machine_mode mode
, rtx x
)
565 int ambient_force_addr
= flag_force_addr
;
569 val
= memory_address (mode
, x
);
570 flag_force_addr
= ambient_force_addr
;
574 /* Convert a mem ref into one with a valid memory address.
575 Pass through anything else unchanged. */
578 validize_mem (rtx ref
)
580 if (GET_CODE (ref
) != MEM
)
582 if (! (flag_force_addr
&& CONSTANT_ADDRESS_P (XEXP (ref
, 0)))
583 && memory_address_p (GET_MODE (ref
), XEXP (ref
, 0)))
586 /* Don't alter REF itself, since that is probably a stack slot. */
587 return replace_equiv_address (ref
, XEXP (ref
, 0));
590 /* Given REF, either a MEM or a REG, and T, either the type of X or
591 the expression corresponding to REF, set RTX_UNCHANGING_P if
595 maybe_set_unchanging (rtx ref
, tree t
)
597 /* We can set RTX_UNCHANGING_P from TREE_READONLY for decls whose
598 initialization is only executed once, or whose initializer always
599 has the same value. Currently we simplify this to PARM_DECLs in the
600 first case, and decls with TREE_CONSTANT initializers in the second.
602 We cannot do this for non-static aggregates, because of the double
603 writes that can be generated by store_constructor, depending on the
604 contents of the initializer. Yes, this does eliminate a good fraction
605 of the number of uses of RTX_UNCHANGING_P for a language like Ada.
606 It also eliminates a good quantity of bugs. Let this be incentive to
607 eliminate RTX_UNCHANGING_P entirely in favor of a more reliable
608 solution, perhaps based on alias sets. */
610 if ((TREE_READONLY (t
) && DECL_P (t
)
611 && (TREE_STATIC (t
) || ! AGGREGATE_TYPE_P (TREE_TYPE (t
)))
612 && (TREE_CODE (t
) == PARM_DECL
613 || (DECL_INITIAL (t
) && TREE_CONSTANT (DECL_INITIAL (t
)))))
614 || TREE_CODE_CLASS (TREE_CODE (t
)) == 'c')
615 RTX_UNCHANGING_P (ref
) = 1;
618 /* Return a modified copy of X with its memory address copied
619 into a temporary register to protect it from side effects.
620 If X is not a MEM, it is returned unchanged (and not copied).
621 Perhaps even if it is a MEM, if there is no need to change it. */
626 if (GET_CODE (x
) != MEM
627 || ! rtx_unstable_p (XEXP (x
, 0)))
631 replace_equiv_address (x
, force_reg (Pmode
, copy_all_regs (XEXP (x
, 0))));
634 /* Copy the value or contents of X to a new temp reg and return that reg. */
639 rtx temp
= gen_reg_rtx (GET_MODE (x
));
641 /* If not an operand, must be an address with PLUS and MULT so
642 do the computation. */
643 if (! general_operand (x
, VOIDmode
))
644 x
= force_operand (x
, temp
);
647 emit_move_insn (temp
, x
);
652 /* Like copy_to_reg but always give the new register mode Pmode
653 in case X is a constant. */
656 copy_addr_to_reg (rtx x
)
658 return copy_to_mode_reg (Pmode
, x
);
661 /* Like copy_to_reg but always give the new register mode MODE
662 in case X is a constant. */
665 copy_to_mode_reg (enum machine_mode mode
, rtx x
)
667 rtx temp
= gen_reg_rtx (mode
);
669 /* If not an operand, must be an address with PLUS and MULT so
670 do the computation. */
671 if (! general_operand (x
, VOIDmode
))
672 x
= force_operand (x
, temp
);
674 if (GET_MODE (x
) != mode
&& GET_MODE (x
) != VOIDmode
)
677 emit_move_insn (temp
, x
);
681 /* Load X into a register if it is not already one.
682 Use mode MODE for the register.
683 X should be valid for mode MODE, but it may be a constant which
684 is valid for all integer modes; that's why caller must specify MODE.
686 The caller must not alter the value in the register we return,
687 since we mark it as a "constant" register. */
690 force_reg (enum machine_mode mode
, rtx x
)
694 if (GET_CODE (x
) == REG
)
697 if (general_operand (x
, mode
))
699 temp
= gen_reg_rtx (mode
);
700 insn
= emit_move_insn (temp
, x
);
704 temp
= force_operand (x
, NULL_RTX
);
705 if (GET_CODE (temp
) == REG
)
706 insn
= get_last_insn ();
709 rtx temp2
= gen_reg_rtx (mode
);
710 insn
= emit_move_insn (temp2
, temp
);
715 /* Let optimizers know that TEMP's value never changes
716 and that X can be substituted for it. Don't get confused
717 if INSN set something else (such as a SUBREG of TEMP). */
719 && (set
= single_set (insn
)) != 0
720 && SET_DEST (set
) == temp
721 && ! rtx_equal_p (x
, SET_SRC (set
)))
722 set_unique_reg_note (insn
, REG_EQUAL
, x
);
724 /* Let optimizers know that TEMP is a pointer, and if so, the
725 known alignment of that pointer. */
728 if (GET_CODE (x
) == SYMBOL_REF
)
730 align
= BITS_PER_UNIT
;
731 if (SYMBOL_REF_DECL (x
) && DECL_P (SYMBOL_REF_DECL (x
)))
732 align
= DECL_ALIGN (SYMBOL_REF_DECL (x
));
734 else if (GET_CODE (x
) == LABEL_REF
)
735 align
= BITS_PER_UNIT
;
736 else if (GET_CODE (x
) == CONST
737 && GET_CODE (XEXP (x
, 0)) == PLUS
738 && GET_CODE (XEXP (XEXP (x
, 0), 0)) == SYMBOL_REF
739 && GET_CODE (XEXP (XEXP (x
, 0), 1)) == CONST_INT
)
741 rtx s
= XEXP (XEXP (x
, 0), 0);
742 rtx c
= XEXP (XEXP (x
, 0), 1);
746 if (SYMBOL_REF_DECL (s
) && DECL_P (SYMBOL_REF_DECL (s
)))
747 sa
= DECL_ALIGN (SYMBOL_REF_DECL (s
));
749 ca
= exact_log2 (INTVAL (c
) & -INTVAL (c
)) * BITS_PER_UNIT
;
751 align
= MIN (sa
, ca
);
755 mark_reg_pointer (temp
, align
);
761 /* If X is a memory ref, copy its contents to a new temp reg and return
762 that reg. Otherwise, return X. */
765 force_not_mem (rtx x
)
769 if (GET_CODE (x
) != MEM
|| GET_MODE (x
) == BLKmode
)
772 temp
= gen_reg_rtx (GET_MODE (x
));
775 REG_POINTER (temp
) = 1;
777 emit_move_insn (temp
, x
);
781 /* Copy X to TARGET (if it's nonzero and a reg)
782 or to a new temp reg and return that reg.
783 MODE is the mode to use for X in case it is a constant. */
786 copy_to_suggested_reg (rtx x
, rtx target
, enum machine_mode mode
)
790 if (target
&& GET_CODE (target
) == REG
)
793 temp
= gen_reg_rtx (mode
);
795 emit_move_insn (temp
, x
);
799 /* Return the mode to use to store a scalar of TYPE and MODE.
800 PUNSIGNEDP points to the signedness of the type and may be adjusted
801 to show what signedness to use on extension operations.
803 FOR_CALL is nonzero if this call is promoting args for a call. */
806 promote_mode (tree type
, enum machine_mode mode
, int *punsignedp
,
807 int for_call ATTRIBUTE_UNUSED
)
809 enum tree_code code
= TREE_CODE (type
);
810 int unsignedp
= *punsignedp
;
812 #ifdef PROMOTE_FOR_CALL_ONLY
820 case INTEGER_TYPE
: case ENUMERAL_TYPE
: case BOOLEAN_TYPE
:
821 case CHAR_TYPE
: case REAL_TYPE
: case OFFSET_TYPE
:
822 PROMOTE_MODE (mode
, unsignedp
, type
);
826 #ifdef POINTERS_EXTEND_UNSIGNED
830 unsignedp
= POINTERS_EXTEND_UNSIGNED
;
838 *punsignedp
= unsignedp
;
842 /* Adjust the stack pointer by ADJUST (an rtx for a number of bytes).
843 This pops when ADJUST is positive. ADJUST need not be constant. */
846 adjust_stack (rtx adjust
)
849 adjust
= protect_from_queue (adjust
, 0);
851 if (adjust
== const0_rtx
)
854 /* We expect all variable sized adjustments to be multiple of
855 PREFERRED_STACK_BOUNDARY. */
856 if (GET_CODE (adjust
) == CONST_INT
)
857 stack_pointer_delta
-= INTVAL (adjust
);
859 temp
= expand_binop (Pmode
,
860 #ifdef STACK_GROWS_DOWNWARD
865 stack_pointer_rtx
, adjust
, stack_pointer_rtx
, 0,
868 if (temp
!= stack_pointer_rtx
)
869 emit_move_insn (stack_pointer_rtx
, temp
);
872 /* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes).
873 This pushes when ADJUST is positive. ADJUST need not be constant. */
876 anti_adjust_stack (rtx adjust
)
879 adjust
= protect_from_queue (adjust
, 0);
881 if (adjust
== const0_rtx
)
884 /* We expect all variable sized adjustments to be multiple of
885 PREFERRED_STACK_BOUNDARY. */
886 if (GET_CODE (adjust
) == CONST_INT
)
887 stack_pointer_delta
+= INTVAL (adjust
);
889 temp
= expand_binop (Pmode
,
890 #ifdef STACK_GROWS_DOWNWARD
895 stack_pointer_rtx
, adjust
, stack_pointer_rtx
, 0,
898 if (temp
!= stack_pointer_rtx
)
899 emit_move_insn (stack_pointer_rtx
, temp
);
902 /* Round the size of a block to be pushed up to the boundary required
903 by this machine. SIZE is the desired size, which need not be constant. */
906 round_push (rtx size
)
908 int align
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
913 if (GET_CODE (size
) == CONST_INT
)
915 HOST_WIDE_INT
new = (INTVAL (size
) + align
- 1) / align
* align
;
917 if (INTVAL (size
) != new)
918 size
= GEN_INT (new);
922 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
923 but we know it can't. So add ourselves and then do
925 size
= expand_binop (Pmode
, add_optab
, size
, GEN_INT (align
- 1),
926 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
927 size
= expand_divmod (0, TRUNC_DIV_EXPR
, Pmode
, size
, GEN_INT (align
),
929 size
= expand_mult (Pmode
, size
, GEN_INT (align
), NULL_RTX
, 1);
935 /* Save the stack pointer for the purpose in SAVE_LEVEL. PSAVE is a pointer
936 to a previously-created save area. If no save area has been allocated,
937 this function will allocate one. If a save area is specified, it
938 must be of the proper mode.
940 The insns are emitted after insn AFTER, if nonzero, otherwise the insns
941 are emitted at the current position. */
944 emit_stack_save (enum save_level save_level
, rtx
*psave
, rtx after
)
947 /* The default is that we use a move insn and save in a Pmode object. */
948 rtx (*fcn
) (rtx
, rtx
) = gen_move_insn
;
949 enum machine_mode mode
= STACK_SAVEAREA_MODE (save_level
);
951 /* See if this machine has anything special to do for this kind of save. */
954 #ifdef HAVE_save_stack_block
956 if (HAVE_save_stack_block
)
957 fcn
= gen_save_stack_block
;
960 #ifdef HAVE_save_stack_function
962 if (HAVE_save_stack_function
)
963 fcn
= gen_save_stack_function
;
966 #ifdef HAVE_save_stack_nonlocal
968 if (HAVE_save_stack_nonlocal
)
969 fcn
= gen_save_stack_nonlocal
;
976 /* If there is no save area and we have to allocate one, do so. Otherwise
977 verify the save area is the proper mode. */
981 if (mode
!= VOIDmode
)
983 if (save_level
== SAVE_NONLOCAL
)
984 *psave
= sa
= assign_stack_local (mode
, GET_MODE_SIZE (mode
), 0);
986 *psave
= sa
= gen_reg_rtx (mode
);
991 if (mode
== VOIDmode
|| GET_MODE (sa
) != mode
)
1000 /* We must validize inside the sequence, to ensure that any instructions
1001 created by the validize call also get moved to the right place. */
1003 sa
= validize_mem (sa
);
1004 emit_insn (fcn (sa
, stack_pointer_rtx
));
1007 emit_insn_after (seq
, after
);
1012 sa
= validize_mem (sa
);
1013 emit_insn (fcn (sa
, stack_pointer_rtx
));
1017 /* Restore the stack pointer for the purpose in SAVE_LEVEL. SA is the save
1018 area made by emit_stack_save. If it is zero, we have nothing to do.
1020 Put any emitted insns after insn AFTER, if nonzero, otherwise at
1021 current position. */
1024 emit_stack_restore (enum save_level save_level
, rtx sa
, rtx after
)
1026 /* The default is that we use a move insn. */
1027 rtx (*fcn
) (rtx
, rtx
) = gen_move_insn
;
1029 /* See if this machine has anything special to do for this kind of save. */
1032 #ifdef HAVE_restore_stack_block
1034 if (HAVE_restore_stack_block
)
1035 fcn
= gen_restore_stack_block
;
1038 #ifdef HAVE_restore_stack_function
1040 if (HAVE_restore_stack_function
)
1041 fcn
= gen_restore_stack_function
;
1044 #ifdef HAVE_restore_stack_nonlocal
1046 if (HAVE_restore_stack_nonlocal
)
1047 fcn
= gen_restore_stack_nonlocal
;
1056 sa
= validize_mem (sa
);
1057 /* These clobbers prevent the scheduler from moving
1058 references to variable arrays below the code
1059 that deletes (pops) the arrays. */
1060 emit_insn (gen_rtx_CLOBBER (VOIDmode
,
1061 gen_rtx_MEM (BLKmode
,
1062 gen_rtx_SCRATCH (VOIDmode
))));
1063 emit_insn (gen_rtx_CLOBBER (VOIDmode
,
1064 gen_rtx_MEM (BLKmode
, stack_pointer_rtx
)));
1072 emit_insn (fcn (stack_pointer_rtx
, sa
));
1075 emit_insn_after (seq
, after
);
1078 emit_insn (fcn (stack_pointer_rtx
, sa
));
1081 #ifdef SETJMP_VIA_SAVE_AREA
1082 /* Optimize RTL generated by allocate_dynamic_stack_space for targets
1083 where SETJMP_VIA_SAVE_AREA is true. The problem is that on these
1084 platforms, the dynamic stack space used can corrupt the original
1085 frame, thus causing a crash if a longjmp unwinds to it. */
1088 optimize_save_area_alloca (rtx insns
)
1092 for (insn
= insns
; insn
; insn
= NEXT_INSN(insn
))
1096 if (GET_CODE (insn
) != INSN
)
1099 for (note
= REG_NOTES (insn
); note
; note
= XEXP (note
, 1))
1101 if (REG_NOTE_KIND (note
) != REG_SAVE_AREA
)
1104 if (!current_function_calls_setjmp
)
1106 rtx pat
= PATTERN (insn
);
1108 /* If we do not see the note in a pattern matching
1109 these precise characteristics, we did something
1110 entirely wrong in allocate_dynamic_stack_space.
1112 Note, one way this could happen is if SETJMP_VIA_SAVE_AREA
1113 was defined on a machine where stacks grow towards higher
1116 Right now only supported port with stack that grow upward
1117 is the HPPA and it does not define SETJMP_VIA_SAVE_AREA. */
1118 if (GET_CODE (pat
) != SET
1119 || SET_DEST (pat
) != stack_pointer_rtx
1120 || GET_CODE (SET_SRC (pat
)) != MINUS
1121 || XEXP (SET_SRC (pat
), 0) != stack_pointer_rtx
)
1124 /* This will now be transformed into a (set REG REG)
1125 so we can just blow away all the other notes. */
1126 XEXP (SET_SRC (pat
), 1) = XEXP (note
, 0);
1127 REG_NOTES (insn
) = NULL_RTX
;
1131 /* setjmp was called, we must remove the REG_SAVE_AREA
1132 note so that later passes do not get confused by its
1134 if (note
== REG_NOTES (insn
))
1136 REG_NOTES (insn
) = XEXP (note
, 1);
1142 for (srch
= REG_NOTES (insn
); srch
; srch
= XEXP (srch
, 1))
1143 if (XEXP (srch
, 1) == note
)
1146 if (srch
== NULL_RTX
)
1149 XEXP (srch
, 1) = XEXP (note
, 1);
1152 /* Once we've seen the note of interest, we need not look at
1153 the rest of them. */
1158 #endif /* SETJMP_VIA_SAVE_AREA */
1160 /* Return an rtx representing the address of an area of memory dynamically
1161 pushed on the stack. This region of memory is always aligned to
1162 a multiple of BIGGEST_ALIGNMENT.
1164 Any required stack pointer alignment is preserved.
1166 SIZE is an rtx representing the size of the area.
1167 TARGET is a place in which the address can be placed.
1169 KNOWN_ALIGN is the alignment (in bits) that we know SIZE has. */
1172 allocate_dynamic_stack_space (rtx size
, rtx target
, int known_align
)
1174 #ifdef SETJMP_VIA_SAVE_AREA
1175 rtx setjmpless_size
= NULL_RTX
;
1178 /* If we're asking for zero bytes, it doesn't matter what we point
1179 to since we can't dereference it. But return a reasonable
1181 if (size
== const0_rtx
)
1182 return virtual_stack_dynamic_rtx
;
1184 /* Otherwise, show we're calling alloca or equivalent. */
1185 current_function_calls_alloca
= 1;
1187 /* Ensure the size is in the proper mode. */
1188 if (GET_MODE (size
) != VOIDmode
&& GET_MODE (size
) != Pmode
)
1189 size
= convert_to_mode (Pmode
, size
, 1);
1191 /* We can't attempt to minimize alignment necessary, because we don't
1192 know the final value of preferred_stack_boundary yet while executing
1194 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
1196 /* We will need to ensure that the address we return is aligned to
1197 BIGGEST_ALIGNMENT. If STACK_DYNAMIC_OFFSET is defined, we don't
1198 always know its final value at this point in the compilation (it
1199 might depend on the size of the outgoing parameter lists, for
1200 example), so we must align the value to be returned in that case.
1201 (Note that STACK_DYNAMIC_OFFSET will have a default nonzero value if
1202 STACK_POINTER_OFFSET or ACCUMULATE_OUTGOING_ARGS are defined).
1203 We must also do an alignment operation on the returned value if
1204 the stack pointer alignment is less strict that BIGGEST_ALIGNMENT.
1206 If we have to align, we must leave space in SIZE for the hole
1207 that might result from the alignment operation. */
1209 #if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET)
1210 #define MUST_ALIGN 1
1212 #define MUST_ALIGN (PREFERRED_STACK_BOUNDARY < BIGGEST_ALIGNMENT)
1217 = force_operand (plus_constant (size
,
1218 BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
- 1),
1221 #ifdef SETJMP_VIA_SAVE_AREA
1222 /* If setjmp restores regs from a save area in the stack frame,
1223 avoid clobbering the reg save area. Note that the offset of
1224 virtual_incoming_args_rtx includes the preallocated stack args space.
1225 It would be no problem to clobber that, but it's on the wrong side
1226 of the old save area. */
1229 = expand_binop (Pmode
, sub_optab
, virtual_stack_dynamic_rtx
,
1230 stack_pointer_rtx
, NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1232 if (!current_function_calls_setjmp
)
1234 int align
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
1236 /* See optimize_save_area_alloca to understand what is being
1239 /* ??? Code below assumes that the save area needs maximal
1240 alignment. This constraint may be too strong. */
1241 if (PREFERRED_STACK_BOUNDARY
!= BIGGEST_ALIGNMENT
)
1244 if (GET_CODE (size
) == CONST_INT
)
1246 HOST_WIDE_INT
new = INTVAL (size
) / align
* align
;
1248 if (INTVAL (size
) != new)
1249 setjmpless_size
= GEN_INT (new);
1251 setjmpless_size
= size
;
1255 /* Since we know overflow is not possible, we avoid using
1256 CEIL_DIV_EXPR and use TRUNC_DIV_EXPR instead. */
1257 setjmpless_size
= expand_divmod (0, TRUNC_DIV_EXPR
, Pmode
, size
,
1258 GEN_INT (align
), NULL_RTX
, 1);
1259 setjmpless_size
= expand_mult (Pmode
, setjmpless_size
,
1260 GEN_INT (align
), NULL_RTX
, 1);
1262 /* Our optimization works based upon being able to perform a simple
1263 transformation of this RTL into a (set REG REG) so make sure things
1264 did in fact end up in a REG. */
1265 if (!register_operand (setjmpless_size
, Pmode
))
1266 setjmpless_size
= force_reg (Pmode
, setjmpless_size
);
1269 size
= expand_binop (Pmode
, add_optab
, size
, dynamic_offset
,
1270 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1272 #endif /* SETJMP_VIA_SAVE_AREA */
1274 /* Round the size to a multiple of the required stack alignment.
1275 Since the stack if presumed to be rounded before this allocation,
1276 this will maintain the required alignment.
1278 If the stack grows downward, we could save an insn by subtracting
1279 SIZE from the stack pointer and then aligning the stack pointer.
1280 The problem with this is that the stack pointer may be unaligned
1281 between the execution of the subtraction and alignment insns and
1282 some machines do not allow this. Even on those that do, some
1283 signal handlers malfunction if a signal should occur between those
1284 insns. Since this is an extremely rare event, we have no reliable
1285 way of knowing which systems have this problem. So we avoid even
1286 momentarily mis-aligning the stack. */
1288 /* If we added a variable amount to SIZE,
1289 we can no longer assume it is aligned. */
1290 #if !defined (SETJMP_VIA_SAVE_AREA)
1291 if (MUST_ALIGN
|| known_align
% PREFERRED_STACK_BOUNDARY
!= 0)
1293 size
= round_push (size
);
1295 do_pending_stack_adjust ();
1297 /* We ought to be called always on the toplevel and stack ought to be aligned
1299 if (stack_pointer_delta
% (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
))
1302 /* If needed, check that we have the required amount of stack. Take into
1303 account what has already been checked. */
1304 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
1305 probe_stack_range (STACK_CHECK_MAX_FRAME_SIZE
+ STACK_CHECK_PROTECT
, size
);
1307 /* Don't use a TARGET that isn't a pseudo or is the wrong mode. */
1308 if (target
== 0 || GET_CODE (target
) != REG
1309 || REGNO (target
) < FIRST_PSEUDO_REGISTER
1310 || GET_MODE (target
) != Pmode
)
1311 target
= gen_reg_rtx (Pmode
);
1313 mark_reg_pointer (target
, known_align
);
1315 /* Perform the required allocation from the stack. Some systems do
1316 this differently than simply incrementing/decrementing from the
1317 stack pointer, such as acquiring the space by calling malloc(). */
1318 #ifdef HAVE_allocate_stack
1319 if (HAVE_allocate_stack
)
1321 enum machine_mode mode
= STACK_SIZE_MODE
;
1322 insn_operand_predicate_fn pred
;
1324 /* We don't have to check against the predicate for operand 0 since
1325 TARGET is known to be a pseudo of the proper mode, which must
1326 be valid for the operand. For operand 1, convert to the
1327 proper mode and validate. */
1328 if (mode
== VOIDmode
)
1329 mode
= insn_data
[(int) CODE_FOR_allocate_stack
].operand
[1].mode
;
1331 pred
= insn_data
[(int) CODE_FOR_allocate_stack
].operand
[1].predicate
;
1332 if (pred
&& ! ((*pred
) (size
, mode
)))
1333 size
= copy_to_mode_reg (mode
, convert_to_mode (mode
, size
, 1));
1335 emit_insn (gen_allocate_stack (target
, size
));
1340 #ifndef STACK_GROWS_DOWNWARD
1341 emit_move_insn (target
, virtual_stack_dynamic_rtx
);
1344 /* Check stack bounds if necessary. */
1345 if (current_function_limit_stack
)
1348 rtx space_available
= gen_label_rtx ();
1349 #ifdef STACK_GROWS_DOWNWARD
1350 available
= expand_binop (Pmode
, sub_optab
,
1351 stack_pointer_rtx
, stack_limit_rtx
,
1352 NULL_RTX
, 1, OPTAB_WIDEN
);
1354 available
= expand_binop (Pmode
, sub_optab
,
1355 stack_limit_rtx
, stack_pointer_rtx
,
1356 NULL_RTX
, 1, OPTAB_WIDEN
);
1358 emit_cmp_and_jump_insns (available
, size
, GEU
, NULL_RTX
, Pmode
, 1,
1362 emit_insn (gen_trap ());
1365 error ("stack limits not supported on this target");
1367 emit_label (space_available
);
1370 anti_adjust_stack (size
);
1371 #ifdef SETJMP_VIA_SAVE_AREA
1372 if (setjmpless_size
!= NULL_RTX
)
1374 rtx note_target
= get_last_insn ();
1376 REG_NOTES (note_target
)
1377 = gen_rtx_EXPR_LIST (REG_SAVE_AREA
, setjmpless_size
,
1378 REG_NOTES (note_target
));
1380 #endif /* SETJMP_VIA_SAVE_AREA */
1382 #ifdef STACK_GROWS_DOWNWARD
1383 emit_move_insn (target
, virtual_stack_dynamic_rtx
);
1389 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
1390 but we know it can't. So add ourselves and then do
1392 target
= expand_binop (Pmode
, add_optab
, target
,
1393 GEN_INT (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
- 1),
1394 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1395 target
= expand_divmod (0, TRUNC_DIV_EXPR
, Pmode
, target
,
1396 GEN_INT (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
),
1398 target
= expand_mult (Pmode
, target
,
1399 GEN_INT (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
),
1403 /* Record the new stack level for nonlocal gotos. */
1404 if (nonlocal_goto_handler_slots
!= 0)
1405 emit_stack_save (SAVE_NONLOCAL
, &nonlocal_goto_stack_level
, NULL_RTX
);
1410 /* A front end may want to override GCC's stack checking by providing a
1411 run-time routine to call to check the stack, so provide a mechanism for
1412 calling that routine. */
1414 static GTY(()) rtx stack_check_libfunc
;
1417 set_stack_check_libfunc (rtx libfunc
)
1419 stack_check_libfunc
= libfunc
;
1422 /* Emit one stack probe at ADDRESS, an address within the stack. */
1425 emit_stack_probe (rtx address
)
1427 rtx memref
= gen_rtx_MEM (word_mode
, address
);
1429 MEM_VOLATILE_P (memref
) = 1;
1431 if (STACK_CHECK_PROBE_LOAD
)
1432 emit_move_insn (gen_reg_rtx (word_mode
), memref
);
1434 emit_move_insn (memref
, const0_rtx
);
1437 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
1438 FIRST is a constant and size is a Pmode RTX. These are offsets from the
1439 current stack pointer. STACK_GROWS_DOWNWARD says whether to add or
1440 subtract from the stack. If SIZE is constant, this is done
1441 with a fixed number of probes. Otherwise, we must make a loop. */
1443 #ifdef STACK_GROWS_DOWNWARD
1444 #define STACK_GROW_OP MINUS
1446 #define STACK_GROW_OP PLUS
1450 probe_stack_range (HOST_WIDE_INT first
, rtx size
)
1452 /* First ensure SIZE is Pmode. */
1453 if (GET_MODE (size
) != VOIDmode
&& GET_MODE (size
) != Pmode
)
1454 size
= convert_to_mode (Pmode
, size
, 1);
1456 /* Next see if the front end has set up a function for us to call to
1458 if (stack_check_libfunc
!= 0)
1460 rtx addr
= memory_address (QImode
,
1461 gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1463 plus_constant (size
, first
)));
1465 addr
= convert_memory_address (ptr_mode
, addr
);
1466 emit_library_call (stack_check_libfunc
, LCT_NORMAL
, VOIDmode
, 1, addr
,
1470 /* Next see if we have an insn to check the stack. Use it if so. */
1471 #ifdef HAVE_check_stack
1472 else if (HAVE_check_stack
)
1474 insn_operand_predicate_fn pred
;
1476 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1478 plus_constant (size
, first
)),
1481 pred
= insn_data
[(int) CODE_FOR_check_stack
].operand
[0].predicate
;
1482 if (pred
&& ! ((*pred
) (last_addr
, Pmode
)))
1483 last_addr
= copy_to_mode_reg (Pmode
, last_addr
);
1485 emit_insn (gen_check_stack (last_addr
));
1489 /* If we have to generate explicit probes, see if we have a constant
1490 small number of them to generate. If so, that's the easy case. */
1491 else if (GET_CODE (size
) == CONST_INT
1492 && INTVAL (size
) < 10 * STACK_CHECK_PROBE_INTERVAL
)
1494 HOST_WIDE_INT offset
;
1496 /* Start probing at FIRST + N * STACK_CHECK_PROBE_INTERVAL
1497 for values of N from 1 until it exceeds LAST. If only one
1498 probe is needed, this will not generate any code. Then probe
1500 for (offset
= first
+ STACK_CHECK_PROBE_INTERVAL
;
1501 offset
< INTVAL (size
);
1502 offset
= offset
+ STACK_CHECK_PROBE_INTERVAL
)
1503 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1507 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1509 plus_constant (size
, first
)));
1512 /* In the variable case, do the same as above, but in a loop. We emit loop
1513 notes so that loop optimization can be done. */
1517 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1519 GEN_INT (first
+ STACK_CHECK_PROBE_INTERVAL
)),
1522 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1524 plus_constant (size
, first
)),
1526 rtx incr
= GEN_INT (STACK_CHECK_PROBE_INTERVAL
);
1527 rtx loop_lab
= gen_label_rtx ();
1528 rtx test_lab
= gen_label_rtx ();
1529 rtx end_lab
= gen_label_rtx ();
1532 if (GET_CODE (test_addr
) != REG
1533 || REGNO (test_addr
) < FIRST_PSEUDO_REGISTER
)
1534 test_addr
= force_reg (Pmode
, test_addr
);
1536 emit_note (NOTE_INSN_LOOP_BEG
);
1537 emit_jump (test_lab
);
1539 emit_label (loop_lab
);
1540 emit_stack_probe (test_addr
);
1542 emit_note (NOTE_INSN_LOOP_CONT
);
1544 #ifdef STACK_GROWS_DOWNWARD
1545 #define CMP_OPCODE GTU
1546 temp
= expand_binop (Pmode
, sub_optab
, test_addr
, incr
, test_addr
,
1549 #define CMP_OPCODE LTU
1550 temp
= expand_binop (Pmode
, add_optab
, test_addr
, incr
, test_addr
,
1554 if (temp
!= test_addr
)
1557 emit_label (test_lab
);
1558 emit_cmp_and_jump_insns (test_addr
, last_addr
, CMP_OPCODE
,
1559 NULL_RTX
, Pmode
, 1, loop_lab
);
1560 emit_jump (end_lab
);
1561 emit_note (NOTE_INSN_LOOP_END
);
1562 emit_label (end_lab
);
1564 emit_stack_probe (last_addr
);
1568 /* Return an rtx representing the register or memory location
1569 in which a scalar value of data type VALTYPE
1570 was returned by a function call to function FUNC.
1571 FUNC is a FUNCTION_DECL node if the precise function is known,
1573 OUTGOING is 1 if on a machine with register windows this function
1574 should return the register in which the function will put its result
1578 hard_function_value (tree valtype
, tree func ATTRIBUTE_UNUSED
,
1579 int outgoing ATTRIBUTE_UNUSED
)
1583 #ifdef FUNCTION_OUTGOING_VALUE
1585 val
= FUNCTION_OUTGOING_VALUE (valtype
, func
);
1588 val
= FUNCTION_VALUE (valtype
, func
);
1590 if (GET_CODE (val
) == REG
1591 && GET_MODE (val
) == BLKmode
)
1593 unsigned HOST_WIDE_INT bytes
= int_size_in_bytes (valtype
);
1594 enum machine_mode tmpmode
;
1596 /* int_size_in_bytes can return -1. We don't need a check here
1597 since the value of bytes will be large enough that no mode
1598 will match and we will abort later in this function. */
1600 for (tmpmode
= GET_CLASS_NARROWEST_MODE (MODE_INT
);
1601 tmpmode
!= VOIDmode
;
1602 tmpmode
= GET_MODE_WIDER_MODE (tmpmode
))
1604 /* Have we found a large enough mode? */
1605 if (GET_MODE_SIZE (tmpmode
) >= bytes
)
1609 /* No suitable mode found. */
1610 if (tmpmode
== VOIDmode
)
1613 PUT_MODE (val
, tmpmode
);
1618 /* Return an rtx representing the register or memory location
1619 in which a scalar value of mode MODE was returned by a library call. */
1622 hard_libcall_value (enum machine_mode mode
)
1624 return LIBCALL_VALUE (mode
);
1627 /* Look up the tree code for a given rtx code
1628 to provide the arithmetic operation for REAL_ARITHMETIC.
1629 The function returns an int because the caller may not know
1630 what `enum tree_code' means. */
1633 rtx_to_tree_code (enum rtx_code code
)
1635 enum tree_code tcode
;
1658 tcode
= LAST_AND_UNUSED_TREE_CODE
;
1661 return ((int) tcode
);
1664 #include "gt-explow.h"