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
));
773 emit_move_insn (temp
, x
);
777 /* Copy X to TARGET (if it's nonzero and a reg)
778 or to a new temp reg and return that reg.
779 MODE is the mode to use for X in case it is a constant. */
782 copy_to_suggested_reg (rtx x
, rtx target
, enum machine_mode mode
)
786 if (target
&& GET_CODE (target
) == REG
)
789 temp
= gen_reg_rtx (mode
);
791 emit_move_insn (temp
, x
);
795 /* Return the mode to use to store a scalar of TYPE and MODE.
796 PUNSIGNEDP points to the signedness of the type and may be adjusted
797 to show what signedness to use on extension operations.
799 FOR_CALL is nonzero if this call is promoting args for a call. */
802 promote_mode (tree type
, enum machine_mode mode
, int *punsignedp
,
803 int for_call ATTRIBUTE_UNUSED
)
805 enum tree_code code
= TREE_CODE (type
);
806 int unsignedp
= *punsignedp
;
808 #ifdef PROMOTE_FOR_CALL_ONLY
816 case INTEGER_TYPE
: case ENUMERAL_TYPE
: case BOOLEAN_TYPE
:
817 case CHAR_TYPE
: case REAL_TYPE
: case OFFSET_TYPE
:
818 PROMOTE_MODE (mode
, unsignedp
, type
);
822 #ifdef POINTERS_EXTEND_UNSIGNED
826 unsignedp
= POINTERS_EXTEND_UNSIGNED
;
834 *punsignedp
= unsignedp
;
838 /* Adjust the stack pointer by ADJUST (an rtx for a number of bytes).
839 This pops when ADJUST is positive. ADJUST need not be constant. */
842 adjust_stack (rtx adjust
)
845 adjust
= protect_from_queue (adjust
, 0);
847 if (adjust
== const0_rtx
)
850 /* We expect all variable sized adjustments to be multiple of
851 PREFERRED_STACK_BOUNDARY. */
852 if (GET_CODE (adjust
) == CONST_INT
)
853 stack_pointer_delta
-= INTVAL (adjust
);
855 temp
= expand_binop (Pmode
,
856 #ifdef STACK_GROWS_DOWNWARD
861 stack_pointer_rtx
, adjust
, stack_pointer_rtx
, 0,
864 if (temp
!= stack_pointer_rtx
)
865 emit_move_insn (stack_pointer_rtx
, temp
);
868 /* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes).
869 This pushes when ADJUST is positive. ADJUST need not be constant. */
872 anti_adjust_stack (rtx adjust
)
875 adjust
= protect_from_queue (adjust
, 0);
877 if (adjust
== const0_rtx
)
880 /* We expect all variable sized adjustments to be multiple of
881 PREFERRED_STACK_BOUNDARY. */
882 if (GET_CODE (adjust
) == CONST_INT
)
883 stack_pointer_delta
+= INTVAL (adjust
);
885 temp
= expand_binop (Pmode
,
886 #ifdef STACK_GROWS_DOWNWARD
891 stack_pointer_rtx
, adjust
, stack_pointer_rtx
, 0,
894 if (temp
!= stack_pointer_rtx
)
895 emit_move_insn (stack_pointer_rtx
, temp
);
898 /* Round the size of a block to be pushed up to the boundary required
899 by this machine. SIZE is the desired size, which need not be constant. */
902 round_push (rtx size
)
904 int align
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
909 if (GET_CODE (size
) == CONST_INT
)
911 HOST_WIDE_INT
new = (INTVAL (size
) + align
- 1) / align
* align
;
913 if (INTVAL (size
) != new)
914 size
= GEN_INT (new);
918 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
919 but we know it can't. So add ourselves and then do
921 size
= expand_binop (Pmode
, add_optab
, size
, GEN_INT (align
- 1),
922 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
923 size
= expand_divmod (0, TRUNC_DIV_EXPR
, Pmode
, size
, GEN_INT (align
),
925 size
= expand_mult (Pmode
, size
, GEN_INT (align
), NULL_RTX
, 1);
931 /* Save the stack pointer for the purpose in SAVE_LEVEL. PSAVE is a pointer
932 to a previously-created save area. If no save area has been allocated,
933 this function will allocate one. If a save area is specified, it
934 must be of the proper mode.
936 The insns are emitted after insn AFTER, if nonzero, otherwise the insns
937 are emitted at the current position. */
940 emit_stack_save (enum save_level save_level
, rtx
*psave
, rtx after
)
943 /* The default is that we use a move insn and save in a Pmode object. */
944 rtx (*fcn
) (rtx
, rtx
) = gen_move_insn
;
945 enum machine_mode mode
= STACK_SAVEAREA_MODE (save_level
);
947 /* See if this machine has anything special to do for this kind of save. */
950 #ifdef HAVE_save_stack_block
952 if (HAVE_save_stack_block
)
953 fcn
= gen_save_stack_block
;
956 #ifdef HAVE_save_stack_function
958 if (HAVE_save_stack_function
)
959 fcn
= gen_save_stack_function
;
962 #ifdef HAVE_save_stack_nonlocal
964 if (HAVE_save_stack_nonlocal
)
965 fcn
= gen_save_stack_nonlocal
;
972 /* If there is no save area and we have to allocate one, do so. Otherwise
973 verify the save area is the proper mode. */
977 if (mode
!= VOIDmode
)
979 if (save_level
== SAVE_NONLOCAL
)
980 *psave
= sa
= assign_stack_local (mode
, GET_MODE_SIZE (mode
), 0);
982 *psave
= sa
= gen_reg_rtx (mode
);
987 if (mode
== VOIDmode
|| GET_MODE (sa
) != mode
)
996 /* We must validize inside the sequence, to ensure that any instructions
997 created by the validize call also get moved to the right place. */
999 sa
= validize_mem (sa
);
1000 emit_insn (fcn (sa
, stack_pointer_rtx
));
1003 emit_insn_after (seq
, after
);
1008 sa
= validize_mem (sa
);
1009 emit_insn (fcn (sa
, stack_pointer_rtx
));
1013 /* Restore the stack pointer for the purpose in SAVE_LEVEL. SA is the save
1014 area made by emit_stack_save. If it is zero, we have nothing to do.
1016 Put any emitted insns after insn AFTER, if nonzero, otherwise at
1017 current position. */
1020 emit_stack_restore (enum save_level save_level
, rtx sa
, rtx after
)
1022 /* The default is that we use a move insn. */
1023 rtx (*fcn
) (rtx
, rtx
) = gen_move_insn
;
1025 /* See if this machine has anything special to do for this kind of save. */
1028 #ifdef HAVE_restore_stack_block
1030 if (HAVE_restore_stack_block
)
1031 fcn
= gen_restore_stack_block
;
1034 #ifdef HAVE_restore_stack_function
1036 if (HAVE_restore_stack_function
)
1037 fcn
= gen_restore_stack_function
;
1040 #ifdef HAVE_restore_stack_nonlocal
1042 if (HAVE_restore_stack_nonlocal
)
1043 fcn
= gen_restore_stack_nonlocal
;
1052 sa
= validize_mem (sa
);
1053 /* These clobbers prevent the scheduler from moving
1054 references to variable arrays below the code
1055 that deletes (pops) the arrays. */
1056 emit_insn (gen_rtx_CLOBBER (VOIDmode
,
1057 gen_rtx_MEM (BLKmode
,
1058 gen_rtx_SCRATCH (VOIDmode
))));
1059 emit_insn (gen_rtx_CLOBBER (VOIDmode
,
1060 gen_rtx_MEM (BLKmode
, stack_pointer_rtx
)));
1068 emit_insn (fcn (stack_pointer_rtx
, sa
));
1071 emit_insn_after (seq
, after
);
1074 emit_insn (fcn (stack_pointer_rtx
, sa
));
1077 #ifdef SETJMP_VIA_SAVE_AREA
1078 /* Optimize RTL generated by allocate_dynamic_stack_space for targets
1079 where SETJMP_VIA_SAVE_AREA is true. The problem is that on these
1080 platforms, the dynamic stack space used can corrupt the original
1081 frame, thus causing a crash if a longjmp unwinds to it. */
1084 optimize_save_area_alloca (rtx insns
)
1088 for (insn
= insns
; insn
; insn
= NEXT_INSN(insn
))
1092 if (GET_CODE (insn
) != INSN
)
1095 for (note
= REG_NOTES (insn
); note
; note
= XEXP (note
, 1))
1097 if (REG_NOTE_KIND (note
) != REG_SAVE_AREA
)
1100 if (!current_function_calls_setjmp
)
1102 rtx pat
= PATTERN (insn
);
1104 /* If we do not see the note in a pattern matching
1105 these precise characteristics, we did something
1106 entirely wrong in allocate_dynamic_stack_space.
1108 Note, one way this could happen is if SETJMP_VIA_SAVE_AREA
1109 was defined on a machine where stacks grow towards higher
1112 Right now only supported port with stack that grow upward
1113 is the HPPA and it does not define SETJMP_VIA_SAVE_AREA. */
1114 if (GET_CODE (pat
) != SET
1115 || SET_DEST (pat
) != stack_pointer_rtx
1116 || GET_CODE (SET_SRC (pat
)) != MINUS
1117 || XEXP (SET_SRC (pat
), 0) != stack_pointer_rtx
)
1120 /* This will now be transformed into a (set REG REG)
1121 so we can just blow away all the other notes. */
1122 XEXP (SET_SRC (pat
), 1) = XEXP (note
, 0);
1123 REG_NOTES (insn
) = NULL_RTX
;
1127 /* setjmp was called, we must remove the REG_SAVE_AREA
1128 note so that later passes do not get confused by its
1130 if (note
== REG_NOTES (insn
))
1132 REG_NOTES (insn
) = XEXP (note
, 1);
1138 for (srch
= REG_NOTES (insn
); srch
; srch
= XEXP (srch
, 1))
1139 if (XEXP (srch
, 1) == note
)
1142 if (srch
== NULL_RTX
)
1145 XEXP (srch
, 1) = XEXP (note
, 1);
1148 /* Once we've seen the note of interest, we need not look at
1149 the rest of them. */
1154 #endif /* SETJMP_VIA_SAVE_AREA */
1156 /* Return an rtx representing the address of an area of memory dynamically
1157 pushed on the stack. This region of memory is always aligned to
1158 a multiple of BIGGEST_ALIGNMENT.
1160 Any required stack pointer alignment is preserved.
1162 SIZE is an rtx representing the size of the area.
1163 TARGET is a place in which the address can be placed.
1165 KNOWN_ALIGN is the alignment (in bits) that we know SIZE has. */
1168 allocate_dynamic_stack_space (rtx size
, rtx target
, int known_align
)
1170 #ifdef SETJMP_VIA_SAVE_AREA
1171 rtx setjmpless_size
= NULL_RTX
;
1174 /* If we're asking for zero bytes, it doesn't matter what we point
1175 to since we can't dereference it. But return a reasonable
1177 if (size
== const0_rtx
)
1178 return virtual_stack_dynamic_rtx
;
1180 /* Otherwise, show we're calling alloca or equivalent. */
1181 current_function_calls_alloca
= 1;
1183 /* Ensure the size is in the proper mode. */
1184 if (GET_MODE (size
) != VOIDmode
&& GET_MODE (size
) != Pmode
)
1185 size
= convert_to_mode (Pmode
, size
, 1);
1187 /* We can't attempt to minimize alignment necessary, because we don't
1188 know the final value of preferred_stack_boundary yet while executing
1190 cfun
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
1192 /* We will need to ensure that the address we return is aligned to
1193 BIGGEST_ALIGNMENT. If STACK_DYNAMIC_OFFSET is defined, we don't
1194 always know its final value at this point in the compilation (it
1195 might depend on the size of the outgoing parameter lists, for
1196 example), so we must align the value to be returned in that case.
1197 (Note that STACK_DYNAMIC_OFFSET will have a default nonzero value if
1198 STACK_POINTER_OFFSET or ACCUMULATE_OUTGOING_ARGS are defined).
1199 We must also do an alignment operation on the returned value if
1200 the stack pointer alignment is less strict that BIGGEST_ALIGNMENT.
1202 If we have to align, we must leave space in SIZE for the hole
1203 that might result from the alignment operation. */
1205 #if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET)
1206 #define MUST_ALIGN 1
1208 #define MUST_ALIGN (PREFERRED_STACK_BOUNDARY < BIGGEST_ALIGNMENT)
1213 = force_operand (plus_constant (size
,
1214 BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
- 1),
1217 #ifdef SETJMP_VIA_SAVE_AREA
1218 /* If setjmp restores regs from a save area in the stack frame,
1219 avoid clobbering the reg save area. Note that the offset of
1220 virtual_incoming_args_rtx includes the preallocated stack args space.
1221 It would be no problem to clobber that, but it's on the wrong side
1222 of the old save area. */
1225 = expand_binop (Pmode
, sub_optab
, virtual_stack_dynamic_rtx
,
1226 stack_pointer_rtx
, NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1228 if (!current_function_calls_setjmp
)
1230 int align
= PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
;
1232 /* See optimize_save_area_alloca to understand what is being
1235 /* ??? Code below assumes that the save area needs maximal
1236 alignment. This constraint may be too strong. */
1237 if (PREFERRED_STACK_BOUNDARY
!= BIGGEST_ALIGNMENT
)
1240 if (GET_CODE (size
) == CONST_INT
)
1242 HOST_WIDE_INT
new = INTVAL (size
) / align
* align
;
1244 if (INTVAL (size
) != new)
1245 setjmpless_size
= GEN_INT (new);
1247 setjmpless_size
= size
;
1251 /* Since we know overflow is not possible, we avoid using
1252 CEIL_DIV_EXPR and use TRUNC_DIV_EXPR instead. */
1253 setjmpless_size
= expand_divmod (0, TRUNC_DIV_EXPR
, Pmode
, size
,
1254 GEN_INT (align
), NULL_RTX
, 1);
1255 setjmpless_size
= expand_mult (Pmode
, setjmpless_size
,
1256 GEN_INT (align
), NULL_RTX
, 1);
1258 /* Our optimization works based upon being able to perform a simple
1259 transformation of this RTL into a (set REG REG) so make sure things
1260 did in fact end up in a REG. */
1261 if (!register_operand (setjmpless_size
, Pmode
))
1262 setjmpless_size
= force_reg (Pmode
, setjmpless_size
);
1265 size
= expand_binop (Pmode
, add_optab
, size
, dynamic_offset
,
1266 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1268 #endif /* SETJMP_VIA_SAVE_AREA */
1270 /* Round the size to a multiple of the required stack alignment.
1271 Since the stack if presumed to be rounded before this allocation,
1272 this will maintain the required alignment.
1274 If the stack grows downward, we could save an insn by subtracting
1275 SIZE from the stack pointer and then aligning the stack pointer.
1276 The problem with this is that the stack pointer may be unaligned
1277 between the execution of the subtraction and alignment insns and
1278 some machines do not allow this. Even on those that do, some
1279 signal handlers malfunction if a signal should occur between those
1280 insns. Since this is an extremely rare event, we have no reliable
1281 way of knowing which systems have this problem. So we avoid even
1282 momentarily mis-aligning the stack. */
1284 /* If we added a variable amount to SIZE,
1285 we can no longer assume it is aligned. */
1286 #if !defined (SETJMP_VIA_SAVE_AREA)
1287 if (MUST_ALIGN
|| known_align
% PREFERRED_STACK_BOUNDARY
!= 0)
1289 size
= round_push (size
);
1291 do_pending_stack_adjust ();
1293 /* We ought to be called always on the toplevel and stack ought to be aligned
1295 if (stack_pointer_delta
% (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
))
1298 /* If needed, check that we have the required amount of stack. Take into
1299 account what has already been checked. */
1300 if (flag_stack_check
&& ! STACK_CHECK_BUILTIN
)
1301 probe_stack_range (STACK_CHECK_MAX_FRAME_SIZE
+ STACK_CHECK_PROTECT
, size
);
1303 /* Don't use a TARGET that isn't a pseudo or is the wrong mode. */
1304 if (target
== 0 || GET_CODE (target
) != REG
1305 || REGNO (target
) < FIRST_PSEUDO_REGISTER
1306 || GET_MODE (target
) != Pmode
)
1307 target
= gen_reg_rtx (Pmode
);
1309 mark_reg_pointer (target
, known_align
);
1311 /* Perform the required allocation from the stack. Some systems do
1312 this differently than simply incrementing/decrementing from the
1313 stack pointer, such as acquiring the space by calling malloc(). */
1314 #ifdef HAVE_allocate_stack
1315 if (HAVE_allocate_stack
)
1317 enum machine_mode mode
= STACK_SIZE_MODE
;
1318 insn_operand_predicate_fn pred
;
1320 /* We don't have to check against the predicate for operand 0 since
1321 TARGET is known to be a pseudo of the proper mode, which must
1322 be valid for the operand. For operand 1, convert to the
1323 proper mode and validate. */
1324 if (mode
== VOIDmode
)
1325 mode
= insn_data
[(int) CODE_FOR_allocate_stack
].operand
[1].mode
;
1327 pred
= insn_data
[(int) CODE_FOR_allocate_stack
].operand
[1].predicate
;
1328 if (pred
&& ! ((*pred
) (size
, mode
)))
1329 size
= copy_to_mode_reg (mode
, convert_to_mode (mode
, size
, 1));
1331 emit_insn (gen_allocate_stack (target
, size
));
1336 #ifndef STACK_GROWS_DOWNWARD
1337 emit_move_insn (target
, virtual_stack_dynamic_rtx
);
1340 /* Check stack bounds if necessary. */
1341 if (current_function_limit_stack
)
1344 rtx space_available
= gen_label_rtx ();
1345 #ifdef STACK_GROWS_DOWNWARD
1346 available
= expand_binop (Pmode
, sub_optab
,
1347 stack_pointer_rtx
, stack_limit_rtx
,
1348 NULL_RTX
, 1, OPTAB_WIDEN
);
1350 available
= expand_binop (Pmode
, sub_optab
,
1351 stack_limit_rtx
, stack_pointer_rtx
,
1352 NULL_RTX
, 1, OPTAB_WIDEN
);
1354 emit_cmp_and_jump_insns (available
, size
, GEU
, NULL_RTX
, Pmode
, 1,
1358 emit_insn (gen_trap ());
1361 error ("stack limits not supported on this target");
1363 emit_label (space_available
);
1366 anti_adjust_stack (size
);
1367 #ifdef SETJMP_VIA_SAVE_AREA
1368 if (setjmpless_size
!= NULL_RTX
)
1370 rtx note_target
= get_last_insn ();
1372 REG_NOTES (note_target
)
1373 = gen_rtx_EXPR_LIST (REG_SAVE_AREA
, setjmpless_size
,
1374 REG_NOTES (note_target
));
1376 #endif /* SETJMP_VIA_SAVE_AREA */
1378 #ifdef STACK_GROWS_DOWNWARD
1379 emit_move_insn (target
, virtual_stack_dynamic_rtx
);
1385 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
1386 but we know it can't. So add ourselves and then do
1388 target
= expand_binop (Pmode
, add_optab
, target
,
1389 GEN_INT (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
- 1),
1390 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1391 target
= expand_divmod (0, TRUNC_DIV_EXPR
, Pmode
, target
,
1392 GEN_INT (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
),
1394 target
= expand_mult (Pmode
, target
,
1395 GEN_INT (BIGGEST_ALIGNMENT
/ BITS_PER_UNIT
),
1399 /* Record the new stack level for nonlocal gotos. */
1400 if (nonlocal_goto_handler_slots
!= 0)
1401 emit_stack_save (SAVE_NONLOCAL
, &nonlocal_goto_stack_level
, NULL_RTX
);
1406 /* A front end may want to override GCC's stack checking by providing a
1407 run-time routine to call to check the stack, so provide a mechanism for
1408 calling that routine. */
1410 static GTY(()) rtx stack_check_libfunc
;
1413 set_stack_check_libfunc (rtx libfunc
)
1415 stack_check_libfunc
= libfunc
;
1418 /* Emit one stack probe at ADDRESS, an address within the stack. */
1421 emit_stack_probe (rtx address
)
1423 rtx memref
= gen_rtx_MEM (word_mode
, address
);
1425 MEM_VOLATILE_P (memref
) = 1;
1427 if (STACK_CHECK_PROBE_LOAD
)
1428 emit_move_insn (gen_reg_rtx (word_mode
), memref
);
1430 emit_move_insn (memref
, const0_rtx
);
1433 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
1434 FIRST is a constant and size is a Pmode RTX. These are offsets from the
1435 current stack pointer. STACK_GROWS_DOWNWARD says whether to add or
1436 subtract from the stack. If SIZE is constant, this is done
1437 with a fixed number of probes. Otherwise, we must make a loop. */
1439 #ifdef STACK_GROWS_DOWNWARD
1440 #define STACK_GROW_OP MINUS
1442 #define STACK_GROW_OP PLUS
1446 probe_stack_range (HOST_WIDE_INT first
, rtx size
)
1448 /* First ensure SIZE is Pmode. */
1449 if (GET_MODE (size
) != VOIDmode
&& GET_MODE (size
) != Pmode
)
1450 size
= convert_to_mode (Pmode
, size
, 1);
1452 /* Next see if the front end has set up a function for us to call to
1454 if (stack_check_libfunc
!= 0)
1456 rtx addr
= memory_address (QImode
,
1457 gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1459 plus_constant (size
, first
)));
1461 addr
= convert_memory_address (ptr_mode
, addr
);
1462 emit_library_call (stack_check_libfunc
, LCT_NORMAL
, VOIDmode
, 1, addr
,
1466 /* Next see if we have an insn to check the stack. Use it if so. */
1467 #ifdef HAVE_check_stack
1468 else if (HAVE_check_stack
)
1470 insn_operand_predicate_fn pred
;
1472 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1474 plus_constant (size
, first
)),
1477 pred
= insn_data
[(int) CODE_FOR_check_stack
].operand
[0].predicate
;
1478 if (pred
&& ! ((*pred
) (last_addr
, Pmode
)))
1479 last_addr
= copy_to_mode_reg (Pmode
, last_addr
);
1481 emit_insn (gen_check_stack (last_addr
));
1485 /* If we have to generate explicit probes, see if we have a constant
1486 small number of them to generate. If so, that's the easy case. */
1487 else if (GET_CODE (size
) == CONST_INT
1488 && INTVAL (size
) < 10 * STACK_CHECK_PROBE_INTERVAL
)
1490 HOST_WIDE_INT offset
;
1492 /* Start probing at FIRST + N * STACK_CHECK_PROBE_INTERVAL
1493 for values of N from 1 until it exceeds LAST. If only one
1494 probe is needed, this will not generate any code. Then probe
1496 for (offset
= first
+ STACK_CHECK_PROBE_INTERVAL
;
1497 offset
< INTVAL (size
);
1498 offset
= offset
+ STACK_CHECK_PROBE_INTERVAL
)
1499 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1503 emit_stack_probe (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1505 plus_constant (size
, first
)));
1508 /* In the variable case, do the same as above, but in a loop. We emit loop
1509 notes so that loop optimization can be done. */
1513 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1515 GEN_INT (first
+ STACK_CHECK_PROBE_INTERVAL
)),
1518 = force_operand (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1520 plus_constant (size
, first
)),
1522 rtx incr
= GEN_INT (STACK_CHECK_PROBE_INTERVAL
);
1523 rtx loop_lab
= gen_label_rtx ();
1524 rtx test_lab
= gen_label_rtx ();
1525 rtx end_lab
= gen_label_rtx ();
1528 if (GET_CODE (test_addr
) != REG
1529 || REGNO (test_addr
) < FIRST_PSEUDO_REGISTER
)
1530 test_addr
= force_reg (Pmode
, test_addr
);
1532 emit_note (NOTE_INSN_LOOP_BEG
);
1533 emit_jump (test_lab
);
1535 emit_label (loop_lab
);
1536 emit_stack_probe (test_addr
);
1538 emit_note (NOTE_INSN_LOOP_CONT
);
1540 #ifdef STACK_GROWS_DOWNWARD
1541 #define CMP_OPCODE GTU
1542 temp
= expand_binop (Pmode
, sub_optab
, test_addr
, incr
, test_addr
,
1545 #define CMP_OPCODE LTU
1546 temp
= expand_binop (Pmode
, add_optab
, test_addr
, incr
, test_addr
,
1550 if (temp
!= test_addr
)
1553 emit_label (test_lab
);
1554 emit_cmp_and_jump_insns (test_addr
, last_addr
, CMP_OPCODE
,
1555 NULL_RTX
, Pmode
, 1, loop_lab
);
1556 emit_jump (end_lab
);
1557 emit_note (NOTE_INSN_LOOP_END
);
1558 emit_label (end_lab
);
1560 emit_stack_probe (last_addr
);
1564 /* Return an rtx representing the register or memory location
1565 in which a scalar value of data type VALTYPE
1566 was returned by a function call to function FUNC.
1567 FUNC is a FUNCTION_DECL node if the precise function is known,
1569 OUTGOING is 1 if on a machine with register windows this function
1570 should return the register in which the function will put its result
1574 hard_function_value (tree valtype
, tree func ATTRIBUTE_UNUSED
,
1575 int outgoing ATTRIBUTE_UNUSED
)
1579 #ifdef FUNCTION_OUTGOING_VALUE
1581 val
= FUNCTION_OUTGOING_VALUE (valtype
, func
);
1584 val
= FUNCTION_VALUE (valtype
, func
);
1586 if (GET_CODE (val
) == REG
1587 && GET_MODE (val
) == BLKmode
)
1589 unsigned HOST_WIDE_INT bytes
= int_size_in_bytes (valtype
);
1590 enum machine_mode tmpmode
;
1592 /* int_size_in_bytes can return -1. We don't need a check here
1593 since the value of bytes will be large enough that no mode
1594 will match and we will abort later in this function. */
1596 for (tmpmode
= GET_CLASS_NARROWEST_MODE (MODE_INT
);
1597 tmpmode
!= VOIDmode
;
1598 tmpmode
= GET_MODE_WIDER_MODE (tmpmode
))
1600 /* Have we found a large enough mode? */
1601 if (GET_MODE_SIZE (tmpmode
) >= bytes
)
1605 /* No suitable mode found. */
1606 if (tmpmode
== VOIDmode
)
1609 PUT_MODE (val
, tmpmode
);
1614 /* Return an rtx representing the register or memory location
1615 in which a scalar value of mode MODE was returned by a library call. */
1618 hard_libcall_value (enum machine_mode mode
)
1620 return LIBCALL_VALUE (mode
);
1623 /* Look up the tree code for a given rtx code
1624 to provide the arithmetic operation for REAL_ARITHMETIC.
1625 The function returns an int because the caller may not know
1626 what `enum tree_code' means. */
1629 rtx_to_tree_code (enum rtx_code code
)
1631 enum tree_code tcode
;
1654 tcode
= LAST_AND_UNUSED_TREE_CODE
;
1657 return ((int) tcode
);
1660 #include "gt-explow.h"