1 /* Subroutines for manipulating rtx's in semantically interesting ways.
2 Copyright (C) 1987, 1991, 1994, 1995, 1996, 1997, 1998, 1999, 2000,
3 2001, 2002, 2003, 2004, 2005, 2006, 2007, 2008, 2009, 2010, 2011
4 Free Software Foundation, Inc.
6 This file is part of GCC.
8 GCC is free software; you can redistribute it and/or modify it under
9 the terms of the GNU General Public License as published by the Free
10 Software Foundation; either version 3, or (at your option) any later
13 GCC is distributed in the hope that it will be useful, but WITHOUT ANY
14 WARRANTY; without even the implied warranty of MERCHANTABILITY or
15 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
18 You should have received a copy of the GNU General Public License
19 along with GCC; see the file COPYING3. If not see
20 <http://www.gnu.org/licenses/>. */
25 #include "coretypes.h"
27 #include "diagnostic-core.h"
37 #include "hard-reg-set.h"
38 #include "insn-config.h"
41 #include "langhooks.h"
43 #include "common/common-target.h"
46 static rtx
break_out_memory_refs (rtx
);
49 /* Truncate and perhaps sign-extend C as appropriate for MODE. */
52 trunc_int_for_mode (HOST_WIDE_INT c
, enum machine_mode mode
)
54 int width
= GET_MODE_PRECISION (mode
);
56 /* You want to truncate to a _what_? */
57 gcc_assert (SCALAR_INT_MODE_P (mode
));
59 /* Canonicalize BImode to 0 and STORE_FLAG_VALUE. */
61 return c
& 1 ? STORE_FLAG_VALUE
: 0;
63 /* Sign-extend for the requested mode. */
65 if (width
< HOST_BITS_PER_WIDE_INT
)
67 HOST_WIDE_INT sign
= 1;
77 /* Return an rtx for the sum of X and the integer C, given that X has
81 plus_constant (enum machine_mode mode
, rtx x
, HOST_WIDE_INT c
)
88 gcc_assert (GET_MODE (x
) == VOIDmode
|| GET_MODE (x
) == mode
);
101 if (GET_MODE_BITSIZE (mode
) > HOST_BITS_PER_WIDE_INT
)
103 unsigned HOST_WIDE_INT l1
= INTVAL (x
);
104 HOST_WIDE_INT h1
= (l1
>> (HOST_BITS_PER_WIDE_INT
- 1)) ? -1 : 0;
105 unsigned HOST_WIDE_INT l2
= c
;
106 HOST_WIDE_INT h2
= c
< 0 ? -1 : 0;
107 unsigned HOST_WIDE_INT lv
;
110 if (add_double_with_sign (l1
, h1
, l2
, h2
, &lv
, &hv
, false))
113 return immed_double_const (lv
, hv
, VOIDmode
);
116 return GEN_INT (INTVAL (x
) + c
);
120 unsigned HOST_WIDE_INT l1
= CONST_DOUBLE_LOW (x
);
121 HOST_WIDE_INT h1
= CONST_DOUBLE_HIGH (x
);
122 unsigned HOST_WIDE_INT l2
= c
;
123 HOST_WIDE_INT h2
= c
< 0 ? -1 : 0;
124 unsigned HOST_WIDE_INT lv
;
127 if (add_double_with_sign (l1
, h1
, l2
, h2
, &lv
, &hv
, false))
128 /* Sorry, we have no way to represent overflows this wide.
129 To fix, add constant support wider than CONST_DOUBLE. */
130 gcc_assert (GET_MODE_BITSIZE (mode
) <= HOST_BITS_PER_DOUBLE_INT
);
132 return immed_double_const (lv
, hv
, VOIDmode
);
136 /* If this is a reference to the constant pool, try replacing it with
137 a reference to a new constant. If the resulting address isn't
138 valid, don't return it because we have no way to validize it. */
139 if (GET_CODE (XEXP (x
, 0)) == SYMBOL_REF
140 && CONSTANT_POOL_ADDRESS_P (XEXP (x
, 0)))
142 tem
= plus_constant (mode
, get_pool_constant (XEXP (x
, 0)), c
);
143 tem
= force_const_mem (GET_MODE (x
), tem
);
144 if (memory_address_p (GET_MODE (tem
), XEXP (tem
, 0)))
150 /* If adding to something entirely constant, set a flag
151 so that we can add a CONST around the result. */
162 /* The interesting case is adding the integer to a sum. Look
163 for constant term in the sum and combine with C. For an
164 integer constant term or a constant term that is not an
165 explicit integer, we combine or group them together anyway.
167 We may not immediately return from the recursive call here, lest
168 all_constant gets lost. */
170 if (CONSTANT_P (XEXP (x
, 1)))
172 x
= gen_rtx_PLUS (mode
, XEXP (x
, 0),
173 plus_constant (mode
, XEXP (x
, 1), c
));
176 else if (find_constant_term_loc (&y
))
178 /* We need to be careful since X may be shared and we can't
179 modify it in place. */
180 rtx copy
= copy_rtx (x
);
181 rtx
*const_loc
= find_constant_term_loc (©
);
183 *const_loc
= plus_constant (mode
, *const_loc
, c
);
194 x
= gen_rtx_PLUS (mode
, x
, GEN_INT (c
));
196 if (GET_CODE (x
) == SYMBOL_REF
|| GET_CODE (x
) == LABEL_REF
)
198 else if (all_constant
)
199 return gen_rtx_CONST (mode
, x
);
204 /* If X is a sum, return a new sum like X but lacking any constant terms.
205 Add all the removed constant terms into *CONSTPTR.
206 X itself is not altered. The result != X if and only if
207 it is not isomorphic to X. */
210 eliminate_constant_term (rtx x
, rtx
*constptr
)
215 if (GET_CODE (x
) != PLUS
)
218 /* First handle constants appearing at this level explicitly. */
219 if (CONST_INT_P (XEXP (x
, 1))
220 && 0 != (tem
= simplify_binary_operation (PLUS
, GET_MODE (x
), *constptr
,
222 && CONST_INT_P (tem
))
225 return eliminate_constant_term (XEXP (x
, 0), constptr
);
229 x0
= eliminate_constant_term (XEXP (x
, 0), &tem
);
230 x1
= eliminate_constant_term (XEXP (x
, 1), &tem
);
231 if ((x1
!= XEXP (x
, 1) || x0
!= XEXP (x
, 0))
232 && 0 != (tem
= simplify_binary_operation (PLUS
, GET_MODE (x
),
234 && CONST_INT_P (tem
))
237 return gen_rtx_PLUS (GET_MODE (x
), x0
, x1
);
243 /* Return an rtx for the size in bytes of the value of EXP. */
250 if (TREE_CODE (exp
) == WITH_SIZE_EXPR
)
251 size
= TREE_OPERAND (exp
, 1);
254 size
= tree_expr_size (exp
);
256 gcc_assert (size
== SUBSTITUTE_PLACEHOLDER_IN_EXPR (size
, exp
));
259 return expand_expr (size
, NULL_RTX
, TYPE_MODE (sizetype
), EXPAND_NORMAL
);
262 /* Return a wide integer for the size in bytes of the value of EXP, or -1
263 if the size can vary or is larger than an integer. */
266 int_expr_size (tree exp
)
270 if (TREE_CODE (exp
) == WITH_SIZE_EXPR
)
271 size
= TREE_OPERAND (exp
, 1);
274 size
= tree_expr_size (exp
);
278 if (size
== 0 || !host_integerp (size
, 0))
281 return tree_low_cst (size
, 0);
284 /* Return a copy of X in which all memory references
285 and all constants that involve symbol refs
286 have been replaced with new temporary registers.
287 Also emit code to load the memory locations and constants
288 into those registers.
290 If X contains no such constants or memory references,
291 X itself (not a copy) is returned.
293 If a constant is found in the address that is not a legitimate constant
294 in an insn, it is left alone in the hope that it might be valid in the
297 X may contain no arithmetic except addition, subtraction and multiplication.
298 Values returned by expand_expr with 1 for sum_ok fit this constraint. */
301 break_out_memory_refs (rtx x
)
304 || (CONSTANT_P (x
) && CONSTANT_ADDRESS_P (x
)
305 && GET_MODE (x
) != VOIDmode
))
306 x
= force_reg (GET_MODE (x
), x
);
307 else if (GET_CODE (x
) == PLUS
|| GET_CODE (x
) == MINUS
308 || GET_CODE (x
) == MULT
)
310 rtx op0
= break_out_memory_refs (XEXP (x
, 0));
311 rtx op1
= break_out_memory_refs (XEXP (x
, 1));
313 if (op0
!= XEXP (x
, 0) || op1
!= XEXP (x
, 1))
314 x
= simplify_gen_binary (GET_CODE (x
), GET_MODE (x
), op0
, op1
);
320 /* Given X, a memory address in address space AS' pointer mode, convert it to
321 an address in the address space's address mode, or vice versa (TO_MODE says
322 which way). We take advantage of the fact that pointers are not allowed to
323 overflow by commuting arithmetic operations over conversions so that address
324 arithmetic insns can be used. */
327 convert_memory_address_addr_space (enum machine_mode to_mode ATTRIBUTE_UNUSED
,
328 rtx x
, addr_space_t as ATTRIBUTE_UNUSED
)
330 #ifndef POINTERS_EXTEND_UNSIGNED
331 gcc_assert (GET_MODE (x
) == to_mode
|| GET_MODE (x
) == VOIDmode
);
333 #else /* defined(POINTERS_EXTEND_UNSIGNED) */
334 enum machine_mode pointer_mode
, address_mode
, from_mode
;
338 /* If X already has the right mode, just return it. */
339 if (GET_MODE (x
) == to_mode
)
342 pointer_mode
= targetm
.addr_space
.pointer_mode (as
);
343 address_mode
= targetm
.addr_space
.address_mode (as
);
344 from_mode
= to_mode
== pointer_mode
? address_mode
: pointer_mode
;
346 /* Here we handle some special cases. If none of them apply, fall through
347 to the default case. */
348 switch (GET_CODE (x
))
350 CASE_CONST_SCALAR_INT
:
351 if (GET_MODE_SIZE (to_mode
) < GET_MODE_SIZE (from_mode
))
353 else if (POINTERS_EXTEND_UNSIGNED
< 0)
355 else if (POINTERS_EXTEND_UNSIGNED
> 0)
359 temp
= simplify_unary_operation (code
, to_mode
, x
, from_mode
);
365 if ((SUBREG_PROMOTED_VAR_P (x
) || REG_POINTER (SUBREG_REG (x
)))
366 && GET_MODE (SUBREG_REG (x
)) == to_mode
)
367 return SUBREG_REG (x
);
371 temp
= gen_rtx_LABEL_REF (to_mode
, XEXP (x
, 0));
372 LABEL_REF_NONLOCAL_P (temp
) = LABEL_REF_NONLOCAL_P (x
);
377 temp
= shallow_copy_rtx (x
);
378 PUT_MODE (temp
, to_mode
);
383 return gen_rtx_CONST (to_mode
,
384 convert_memory_address_addr_space
385 (to_mode
, XEXP (x
, 0), as
));
390 /* FIXME: For addition, we used to permute the conversion and
391 addition operation only if one operand is a constant and
392 converting the constant does not change it or if one operand
393 is a constant and we are using a ptr_extend instruction
394 (POINTERS_EXTEND_UNSIGNED < 0) even if the resulting address
395 may overflow/underflow. We relax the condition to include
396 zero-extend (POINTERS_EXTEND_UNSIGNED > 0) since the other
397 parts of the compiler depend on it. See PR 49721.
399 We can always safely permute them if we are making the address
401 if (GET_MODE_SIZE (to_mode
) < GET_MODE_SIZE (from_mode
)
402 || (GET_CODE (x
) == PLUS
403 && CONST_INT_P (XEXP (x
, 1))
404 && (POINTERS_EXTEND_UNSIGNED
!= 0
405 || XEXP (x
, 1) == convert_memory_address_addr_space
406 (to_mode
, XEXP (x
, 1), as
))))
407 return gen_rtx_fmt_ee (GET_CODE (x
), to_mode
,
408 convert_memory_address_addr_space
409 (to_mode
, XEXP (x
, 0), as
),
417 return convert_modes (to_mode
, from_mode
,
418 x
, POINTERS_EXTEND_UNSIGNED
);
419 #endif /* defined(POINTERS_EXTEND_UNSIGNED) */
422 /* Return something equivalent to X but valid as a memory address for something
423 of mode MODE in the named address space AS. When X is not itself valid,
424 this works by copying X or subexpressions of it into registers. */
427 memory_address_addr_space (enum machine_mode mode
, rtx x
, addr_space_t as
)
430 enum machine_mode address_mode
= targetm
.addr_space
.address_mode (as
);
432 x
= convert_memory_address_addr_space (address_mode
, x
, as
);
434 /* By passing constant addresses through registers
435 we get a chance to cse them. */
436 if (! cse_not_expected
&& CONSTANT_P (x
) && CONSTANT_ADDRESS_P (x
))
437 x
= force_reg (address_mode
, x
);
439 /* We get better cse by rejecting indirect addressing at this stage.
440 Let the combiner create indirect addresses where appropriate.
441 For now, generate the code so that the subexpressions useful to share
442 are visible. But not if cse won't be done! */
445 if (! cse_not_expected
&& !REG_P (x
))
446 x
= break_out_memory_refs (x
);
448 /* At this point, any valid address is accepted. */
449 if (memory_address_addr_space_p (mode
, x
, as
))
452 /* If it was valid before but breaking out memory refs invalidated it,
453 use it the old way. */
454 if (memory_address_addr_space_p (mode
, oldx
, as
))
460 /* Perform machine-dependent transformations on X
461 in certain cases. This is not necessary since the code
462 below can handle all possible cases, but machine-dependent
463 transformations can make better code. */
466 x
= targetm
.addr_space
.legitimize_address (x
, oldx
, mode
, as
);
467 if (orig_x
!= x
&& memory_address_addr_space_p (mode
, x
, as
))
471 /* PLUS and MULT can appear in special ways
472 as the result of attempts to make an address usable for indexing.
473 Usually they are dealt with by calling force_operand, below.
474 But a sum containing constant terms is special
475 if removing them makes the sum a valid address:
476 then we generate that address in a register
477 and index off of it. We do this because it often makes
478 shorter code, and because the addresses thus generated
479 in registers often become common subexpressions. */
480 if (GET_CODE (x
) == PLUS
)
482 rtx constant_term
= const0_rtx
;
483 rtx y
= eliminate_constant_term (x
, &constant_term
);
484 if (constant_term
== const0_rtx
485 || ! memory_address_addr_space_p (mode
, y
, as
))
486 x
= force_operand (x
, NULL_RTX
);
489 y
= gen_rtx_PLUS (GET_MODE (x
), copy_to_reg (y
), constant_term
);
490 if (! memory_address_addr_space_p (mode
, y
, as
))
491 x
= force_operand (x
, NULL_RTX
);
497 else if (GET_CODE (x
) == MULT
|| GET_CODE (x
) == MINUS
)
498 x
= force_operand (x
, NULL_RTX
);
500 /* If we have a register that's an invalid address,
501 it must be a hard reg of the wrong class. Copy it to a pseudo. */
505 /* Last resort: copy the value to a register, since
506 the register is a valid address. */
508 x
= force_reg (address_mode
, x
);
513 gcc_assert (memory_address_addr_space_p (mode
, x
, as
));
514 /* If we didn't change the address, we are done. Otherwise, mark
515 a reg as a pointer if we have REG or REG + CONST_INT. */
519 mark_reg_pointer (x
, BITS_PER_UNIT
);
520 else if (GET_CODE (x
) == PLUS
521 && REG_P (XEXP (x
, 0))
522 && CONST_INT_P (XEXP (x
, 1)))
523 mark_reg_pointer (XEXP (x
, 0), BITS_PER_UNIT
);
525 /* OLDX may have been the address on a temporary. Update the address
526 to indicate that X is now used. */
527 update_temp_slot_address (oldx
, x
);
532 /* Convert a mem ref into one with a valid memory address.
533 Pass through anything else unchanged. */
536 validize_mem (rtx ref
)
540 ref
= use_anchored_address (ref
);
541 if (memory_address_addr_space_p (GET_MODE (ref
), XEXP (ref
, 0),
542 MEM_ADDR_SPACE (ref
)))
545 /* Don't alter REF itself, since that is probably a stack slot. */
546 return replace_equiv_address (ref
, XEXP (ref
, 0));
549 /* If X is a memory reference to a member of an object block, try rewriting
550 it to use an anchor instead. Return the new memory reference on success
551 and the old one on failure. */
554 use_anchored_address (rtx x
)
557 HOST_WIDE_INT offset
;
558 enum machine_mode mode
;
560 if (!flag_section_anchors
)
566 /* Split the address into a base and offset. */
569 if (GET_CODE (base
) == CONST
570 && GET_CODE (XEXP (base
, 0)) == PLUS
571 && CONST_INT_P (XEXP (XEXP (base
, 0), 1)))
573 offset
+= INTVAL (XEXP (XEXP (base
, 0), 1));
574 base
= XEXP (XEXP (base
, 0), 0);
577 /* Check whether BASE is suitable for anchors. */
578 if (GET_CODE (base
) != SYMBOL_REF
579 || !SYMBOL_REF_HAS_BLOCK_INFO_P (base
)
580 || SYMBOL_REF_ANCHOR_P (base
)
581 || SYMBOL_REF_BLOCK (base
) == NULL
582 || !targetm
.use_anchors_for_symbol_p (base
))
585 /* Decide where BASE is going to be. */
586 place_block_symbol (base
);
588 /* Get the anchor we need to use. */
589 offset
+= SYMBOL_REF_BLOCK_OFFSET (base
);
590 base
= get_section_anchor (SYMBOL_REF_BLOCK (base
), offset
,
591 SYMBOL_REF_TLS_MODEL (base
));
593 /* Work out the offset from the anchor. */
594 offset
-= SYMBOL_REF_BLOCK_OFFSET (base
);
596 /* If we're going to run a CSE pass, force the anchor into a register.
597 We will then be able to reuse registers for several accesses, if the
598 target costs say that that's worthwhile. */
599 mode
= GET_MODE (base
);
600 if (!cse_not_expected
)
601 base
= force_reg (mode
, base
);
603 return replace_equiv_address (x
, plus_constant (mode
, base
, offset
));
606 /* Copy the value or contents of X to a new temp reg and return that reg. */
611 rtx temp
= gen_reg_rtx (GET_MODE (x
));
613 /* If not an operand, must be an address with PLUS and MULT so
614 do the computation. */
615 if (! general_operand (x
, VOIDmode
))
616 x
= force_operand (x
, temp
);
619 emit_move_insn (temp
, x
);
624 /* Like copy_to_reg but always give the new register mode Pmode
625 in case X is a constant. */
628 copy_addr_to_reg (rtx x
)
630 return copy_to_mode_reg (Pmode
, x
);
633 /* Like copy_to_reg but always give the new register mode MODE
634 in case X is a constant. */
637 copy_to_mode_reg (enum machine_mode mode
, rtx x
)
639 rtx temp
= gen_reg_rtx (mode
);
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
);
646 gcc_assert (GET_MODE (x
) == mode
|| GET_MODE (x
) == VOIDmode
);
648 emit_move_insn (temp
, x
);
652 /* Load X into a register if it is not already one.
653 Use mode MODE for the register.
654 X should be valid for mode MODE, but it may be a constant which
655 is valid for all integer modes; that's why caller must specify MODE.
657 The caller must not alter the value in the register we return,
658 since we mark it as a "constant" register. */
661 force_reg (enum machine_mode mode
, rtx x
)
668 if (general_operand (x
, mode
))
670 temp
= gen_reg_rtx (mode
);
671 insn
= emit_move_insn (temp
, x
);
675 temp
= force_operand (x
, NULL_RTX
);
677 insn
= get_last_insn ();
680 rtx temp2
= gen_reg_rtx (mode
);
681 insn
= emit_move_insn (temp2
, temp
);
686 /* Let optimizers know that TEMP's value never changes
687 and that X can be substituted for it. Don't get confused
688 if INSN set something else (such as a SUBREG of TEMP). */
690 && (set
= single_set (insn
)) != 0
691 && SET_DEST (set
) == temp
692 && ! rtx_equal_p (x
, SET_SRC (set
)))
693 set_unique_reg_note (insn
, REG_EQUAL
, x
);
695 /* Let optimizers know that TEMP is a pointer, and if so, the
696 known alignment of that pointer. */
699 if (GET_CODE (x
) == SYMBOL_REF
)
701 align
= BITS_PER_UNIT
;
702 if (SYMBOL_REF_DECL (x
) && DECL_P (SYMBOL_REF_DECL (x
)))
703 align
= DECL_ALIGN (SYMBOL_REF_DECL (x
));
705 else if (GET_CODE (x
) == LABEL_REF
)
706 align
= BITS_PER_UNIT
;
707 else if (GET_CODE (x
) == CONST
708 && GET_CODE (XEXP (x
, 0)) == PLUS
709 && GET_CODE (XEXP (XEXP (x
, 0), 0)) == SYMBOL_REF
710 && CONST_INT_P (XEXP (XEXP (x
, 0), 1)))
712 rtx s
= XEXP (XEXP (x
, 0), 0);
713 rtx c
= XEXP (XEXP (x
, 0), 1);
717 if (SYMBOL_REF_DECL (s
) && DECL_P (SYMBOL_REF_DECL (s
)))
718 sa
= DECL_ALIGN (SYMBOL_REF_DECL (s
));
724 ca
= ctz_hwi (INTVAL (c
)) * BITS_PER_UNIT
;
725 align
= MIN (sa
, ca
);
729 if (align
|| (MEM_P (x
) && MEM_POINTER (x
)))
730 mark_reg_pointer (temp
, align
);
736 /* If X is a memory ref, copy its contents to a new temp reg and return
737 that reg. Otherwise, return X. */
740 force_not_mem (rtx x
)
744 if (!MEM_P (x
) || GET_MODE (x
) == BLKmode
)
747 temp
= gen_reg_rtx (GET_MODE (x
));
750 REG_POINTER (temp
) = 1;
752 emit_move_insn (temp
, x
);
756 /* Copy X to TARGET (if it's nonzero and a reg)
757 or to a new temp reg and return that reg.
758 MODE is the mode to use for X in case it is a constant. */
761 copy_to_suggested_reg (rtx x
, rtx target
, enum machine_mode mode
)
765 if (target
&& REG_P (target
))
768 temp
= gen_reg_rtx (mode
);
770 emit_move_insn (temp
, x
);
774 /* Return the mode to use to pass or return a scalar of TYPE and MODE.
775 PUNSIGNEDP points to the signedness of the type and may be adjusted
776 to show what signedness to use on extension operations.
778 FOR_RETURN is nonzero if the caller is promoting the return value
779 of FNDECL, else it is for promoting args. */
782 promote_function_mode (const_tree type
, enum machine_mode mode
, int *punsignedp
,
783 const_tree funtype
, int for_return
)
785 /* Called without a type node for a libcall. */
786 if (type
== NULL_TREE
)
788 if (INTEGRAL_MODE_P (mode
))
789 return targetm
.calls
.promote_function_mode (NULL_TREE
, mode
,
796 switch (TREE_CODE (type
))
798 case INTEGER_TYPE
: case ENUMERAL_TYPE
: case BOOLEAN_TYPE
:
799 case REAL_TYPE
: case OFFSET_TYPE
: case FIXED_POINT_TYPE
:
800 case POINTER_TYPE
: case REFERENCE_TYPE
:
801 return targetm
.calls
.promote_function_mode (type
, mode
, punsignedp
, funtype
,
808 /* Return the mode to use to store a scalar of TYPE and MODE.
809 PUNSIGNEDP points to the signedness of the type and may be adjusted
810 to show what signedness to use on extension operations. */
813 promote_mode (const_tree type ATTRIBUTE_UNUSED
, enum machine_mode mode
,
814 int *punsignedp ATTRIBUTE_UNUSED
)
821 /* For libcalls this is invoked without TYPE from the backends
822 TARGET_PROMOTE_FUNCTION_MODE hooks. Don't do anything in that
824 if (type
== NULL_TREE
)
827 /* FIXME: this is the same logic that was there until GCC 4.4, but we
828 probably want to test POINTERS_EXTEND_UNSIGNED even if PROMOTE_MODE
829 is not defined. The affected targets are M32C, S390, SPARC. */
831 code
= TREE_CODE (type
);
832 unsignedp
= *punsignedp
;
836 case INTEGER_TYPE
: case ENUMERAL_TYPE
: case BOOLEAN_TYPE
:
837 case REAL_TYPE
: case OFFSET_TYPE
: case FIXED_POINT_TYPE
:
838 PROMOTE_MODE (mode
, unsignedp
, type
);
839 *punsignedp
= unsignedp
;
843 #ifdef POINTERS_EXTEND_UNSIGNED
846 *punsignedp
= POINTERS_EXTEND_UNSIGNED
;
847 return targetm
.addr_space
.address_mode
848 (TYPE_ADDR_SPACE (TREE_TYPE (type
)));
861 /* Use one of promote_mode or promote_function_mode to find the promoted
862 mode of DECL. If PUNSIGNEDP is not NULL, store there the unsignedness
863 of DECL after promotion. */
866 promote_decl_mode (const_tree decl
, int *punsignedp
)
868 tree type
= TREE_TYPE (decl
);
869 int unsignedp
= TYPE_UNSIGNED (type
);
870 enum machine_mode mode
= DECL_MODE (decl
);
871 enum machine_mode pmode
;
873 if (TREE_CODE (decl
) == RESULT_DECL
874 || TREE_CODE (decl
) == PARM_DECL
)
875 pmode
= promote_function_mode (type
, mode
, &unsignedp
,
876 TREE_TYPE (current_function_decl
), 2);
878 pmode
= promote_mode (type
, mode
, &unsignedp
);
881 *punsignedp
= unsignedp
;
886 /* Controls the behaviour of {anti_,}adjust_stack. */
887 static bool suppress_reg_args_size
;
889 /* A helper for adjust_stack and anti_adjust_stack. */
892 adjust_stack_1 (rtx adjust
, bool anti_p
)
896 #ifndef STACK_GROWS_DOWNWARD
897 /* Hereafter anti_p means subtract_p. */
901 temp
= expand_binop (Pmode
,
902 anti_p
? sub_optab
: add_optab
,
903 stack_pointer_rtx
, adjust
, stack_pointer_rtx
, 0,
906 if (temp
!= stack_pointer_rtx
)
907 insn
= emit_move_insn (stack_pointer_rtx
, temp
);
910 insn
= get_last_insn ();
911 temp
= single_set (insn
);
912 gcc_assert (temp
!= NULL
&& SET_DEST (temp
) == stack_pointer_rtx
);
915 if (!suppress_reg_args_size
)
916 add_reg_note (insn
, REG_ARGS_SIZE
, GEN_INT (stack_pointer_delta
));
919 /* Adjust the stack pointer by ADJUST (an rtx for a number of bytes).
920 This pops when ADJUST is positive. ADJUST need not be constant. */
923 adjust_stack (rtx adjust
)
925 if (adjust
== const0_rtx
)
928 /* We expect all variable sized adjustments to be multiple of
929 PREFERRED_STACK_BOUNDARY. */
930 if (CONST_INT_P (adjust
))
931 stack_pointer_delta
-= INTVAL (adjust
);
933 adjust_stack_1 (adjust
, false);
936 /* Adjust the stack pointer by minus ADJUST (an rtx for a number of bytes).
937 This pushes when ADJUST is positive. ADJUST need not be constant. */
940 anti_adjust_stack (rtx adjust
)
942 if (adjust
== const0_rtx
)
945 /* We expect all variable sized adjustments to be multiple of
946 PREFERRED_STACK_BOUNDARY. */
947 if (CONST_INT_P (adjust
))
948 stack_pointer_delta
+= INTVAL (adjust
);
950 adjust_stack_1 (adjust
, true);
953 /* Round the size of a block to be pushed up to the boundary required
954 by this machine. SIZE is the desired size, which need not be constant. */
957 round_push (rtx size
)
959 rtx align_rtx
, alignm1_rtx
;
961 if (!SUPPORTS_STACK_ALIGNMENT
962 || crtl
->preferred_stack_boundary
== MAX_SUPPORTED_STACK_ALIGNMENT
)
964 int align
= crtl
->preferred_stack_boundary
/ BITS_PER_UNIT
;
969 if (CONST_INT_P (size
))
971 HOST_WIDE_INT new_size
= (INTVAL (size
) + align
- 1) / align
* align
;
973 if (INTVAL (size
) != new_size
)
974 size
= GEN_INT (new_size
);
978 align_rtx
= GEN_INT (align
);
979 alignm1_rtx
= GEN_INT (align
- 1);
983 /* If crtl->preferred_stack_boundary might still grow, use
984 virtual_preferred_stack_boundary_rtx instead. This will be
985 substituted by the right value in vregs pass and optimized
987 align_rtx
= virtual_preferred_stack_boundary_rtx
;
988 alignm1_rtx
= force_operand (plus_constant (Pmode
, align_rtx
, -1),
992 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
993 but we know it can't. So add ourselves and then do
995 size
= expand_binop (Pmode
, add_optab
, size
, alignm1_rtx
,
996 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
997 size
= expand_divmod (0, TRUNC_DIV_EXPR
, Pmode
, size
, align_rtx
,
999 size
= expand_mult (Pmode
, size
, align_rtx
, NULL_RTX
, 1);
1004 /* Save the stack pointer for the purpose in SAVE_LEVEL. PSAVE is a pointer
1005 to a previously-created save area. If no save area has been allocated,
1006 this function will allocate one. If a save area is specified, it
1007 must be of the proper mode. */
1010 emit_stack_save (enum save_level save_level
, rtx
*psave
)
1013 /* The default is that we use a move insn and save in a Pmode object. */
1014 rtx (*fcn
) (rtx
, rtx
) = gen_move_insn
;
1015 enum machine_mode mode
= STACK_SAVEAREA_MODE (save_level
);
1017 /* See if this machine has anything special to do for this kind of save. */
1020 #ifdef HAVE_save_stack_block
1022 if (HAVE_save_stack_block
)
1023 fcn
= gen_save_stack_block
;
1026 #ifdef HAVE_save_stack_function
1028 if (HAVE_save_stack_function
)
1029 fcn
= gen_save_stack_function
;
1032 #ifdef HAVE_save_stack_nonlocal
1034 if (HAVE_save_stack_nonlocal
)
1035 fcn
= gen_save_stack_nonlocal
;
1042 /* If there is no save area and we have to allocate one, do so. Otherwise
1043 verify the save area is the proper mode. */
1047 if (mode
!= VOIDmode
)
1049 if (save_level
== SAVE_NONLOCAL
)
1050 *psave
= sa
= assign_stack_local (mode
, GET_MODE_SIZE (mode
), 0);
1052 *psave
= sa
= gen_reg_rtx (mode
);
1056 do_pending_stack_adjust ();
1058 sa
= validize_mem (sa
);
1059 emit_insn (fcn (sa
, stack_pointer_rtx
));
1062 /* Restore the stack pointer for the purpose in SAVE_LEVEL. SA is the save
1063 area made by emit_stack_save. If it is zero, we have nothing to do. */
1066 emit_stack_restore (enum save_level save_level
, rtx sa
)
1068 /* The default is that we use a move insn. */
1069 rtx (*fcn
) (rtx
, rtx
) = gen_move_insn
;
1071 /* If stack_realign_drap, the x86 backend emits a prologue that aligns both
1072 STACK_POINTER and HARD_FRAME_POINTER.
1073 If stack_realign_fp, the x86 backend emits a prologue that aligns only
1074 STACK_POINTER. This renders the HARD_FRAME_POINTER unusable for accessing
1075 aligned variables, which is reflected in ix86_can_eliminate.
1076 We normally still have the realigned STACK_POINTER that we can use.
1077 But if there is a stack restore still present at reload, it can trigger
1078 mark_not_eliminable for the STACK_POINTER, leaving no way to eliminate
1079 FRAME_POINTER into a hard reg.
1080 To prevent this situation, we force need_drap if we emit a stack
1082 if (SUPPORTS_STACK_ALIGNMENT
)
1083 crtl
->need_drap
= true;
1085 /* See if this machine has anything special to do for this kind of save. */
1088 #ifdef HAVE_restore_stack_block
1090 if (HAVE_restore_stack_block
)
1091 fcn
= gen_restore_stack_block
;
1094 #ifdef HAVE_restore_stack_function
1096 if (HAVE_restore_stack_function
)
1097 fcn
= gen_restore_stack_function
;
1100 #ifdef HAVE_restore_stack_nonlocal
1102 if (HAVE_restore_stack_nonlocal
)
1103 fcn
= gen_restore_stack_nonlocal
;
1112 sa
= validize_mem (sa
);
1113 /* These clobbers prevent the scheduler from moving
1114 references to variable arrays below the code
1115 that deletes (pops) the arrays. */
1116 emit_clobber (gen_rtx_MEM (BLKmode
, gen_rtx_SCRATCH (VOIDmode
)));
1117 emit_clobber (gen_rtx_MEM (BLKmode
, stack_pointer_rtx
));
1120 discard_pending_stack_adjust ();
1122 emit_insn (fcn (stack_pointer_rtx
, sa
));
1125 /* Invoke emit_stack_save on the nonlocal_goto_save_area for the current
1126 function. This function should be called whenever we allocate or
1127 deallocate dynamic stack space. */
1130 update_nonlocal_goto_save_area (void)
1135 /* The nonlocal_goto_save_area object is an array of N pointers. The
1136 first one is used for the frame pointer save; the rest are sized by
1137 STACK_SAVEAREA_MODE. Create a reference to array index 1, the first
1138 of the stack save area slots. */
1139 t_save
= build4 (ARRAY_REF
,
1140 TREE_TYPE (TREE_TYPE (cfun
->nonlocal_goto_save_area
)),
1141 cfun
->nonlocal_goto_save_area
,
1142 integer_one_node
, NULL_TREE
, NULL_TREE
);
1143 r_save
= expand_expr (t_save
, NULL_RTX
, VOIDmode
, EXPAND_WRITE
);
1145 emit_stack_save (SAVE_NONLOCAL
, &r_save
);
1148 /* Return an rtx representing the address of an area of memory dynamically
1149 pushed on the stack.
1151 Any required stack pointer alignment is preserved.
1153 SIZE is an rtx representing the size of the area.
1155 SIZE_ALIGN is the alignment (in bits) that we know SIZE has. This
1156 parameter may be zero. If so, a proper value will be extracted
1157 from SIZE if it is constant, otherwise BITS_PER_UNIT will be assumed.
1159 REQUIRED_ALIGN is the alignment (in bits) required for the region
1162 If CANNOT_ACCUMULATE is set to TRUE, the caller guarantees that the
1163 stack space allocated by the generated code cannot be added with itself
1164 in the course of the execution of the function. It is always safe to
1165 pass FALSE here and the following criterion is sufficient in order to
1166 pass TRUE: every path in the CFG that starts at the allocation point and
1167 loops to it executes the associated deallocation code. */
1170 allocate_dynamic_stack_space (rtx size
, unsigned size_align
,
1171 unsigned required_align
, bool cannot_accumulate
)
1173 HOST_WIDE_INT stack_usage_size
= -1;
1174 rtx final_label
, final_target
, target
;
1175 unsigned extra_align
= 0;
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 cfun
->calls_alloca
= 1;
1187 /* If stack usage info is requested, look into the size we are passed.
1188 We need to do so this early to avoid the obfuscation that may be
1189 introduced later by the various alignment operations. */
1190 if (flag_stack_usage_info
)
1192 if (CONST_INT_P (size
))
1193 stack_usage_size
= INTVAL (size
);
1194 else if (REG_P (size
))
1196 /* Look into the last emitted insn and see if we can deduce
1197 something for the register. */
1198 rtx insn
, set
, note
;
1199 insn
= get_last_insn ();
1200 if ((set
= single_set (insn
)) && rtx_equal_p (SET_DEST (set
), size
))
1202 if (CONST_INT_P (SET_SRC (set
)))
1203 stack_usage_size
= INTVAL (SET_SRC (set
));
1204 else if ((note
= find_reg_equal_equiv_note (insn
))
1205 && CONST_INT_P (XEXP (note
, 0)))
1206 stack_usage_size
= INTVAL (XEXP (note
, 0));
1210 /* If the size is not constant, we can't say anything. */
1211 if (stack_usage_size
== -1)
1213 current_function_has_unbounded_dynamic_stack_size
= 1;
1214 stack_usage_size
= 0;
1218 /* Ensure the size is in the proper mode. */
1219 if (GET_MODE (size
) != VOIDmode
&& GET_MODE (size
) != Pmode
)
1220 size
= convert_to_mode (Pmode
, size
, 1);
1222 /* Adjust SIZE_ALIGN, if needed. */
1223 if (CONST_INT_P (size
))
1225 unsigned HOST_WIDE_INT lsb
;
1227 lsb
= INTVAL (size
);
1230 /* Watch out for overflow truncating to "unsigned". */
1231 if (lsb
> UINT_MAX
/ BITS_PER_UNIT
)
1232 size_align
= 1u << (HOST_BITS_PER_INT
- 1);
1234 size_align
= (unsigned)lsb
* BITS_PER_UNIT
;
1236 else if (size_align
< BITS_PER_UNIT
)
1237 size_align
= BITS_PER_UNIT
;
1239 /* We can't attempt to minimize alignment necessary, because we don't
1240 know the final value of preferred_stack_boundary yet while executing
1242 if (crtl
->preferred_stack_boundary
< PREFERRED_STACK_BOUNDARY
)
1243 crtl
->preferred_stack_boundary
= PREFERRED_STACK_BOUNDARY
;
1245 /* We will need to ensure that the address we return is aligned to
1246 REQUIRED_ALIGN. If STACK_DYNAMIC_OFFSET is defined, we don't
1247 always know its final value at this point in the compilation (it
1248 might depend on the size of the outgoing parameter lists, for
1249 example), so we must align the value to be returned in that case.
1250 (Note that STACK_DYNAMIC_OFFSET will have a default nonzero value if
1251 STACK_POINTER_OFFSET or ACCUMULATE_OUTGOING_ARGS are defined).
1252 We must also do an alignment operation on the returned value if
1253 the stack pointer alignment is less strict than REQUIRED_ALIGN.
1255 If we have to align, we must leave space in SIZE for the hole
1256 that might result from the alignment operation. */
1258 must_align
= (crtl
->preferred_stack_boundary
< required_align
);
1261 if (required_align
> PREFERRED_STACK_BOUNDARY
)
1262 extra_align
= PREFERRED_STACK_BOUNDARY
;
1263 else if (required_align
> STACK_BOUNDARY
)
1264 extra_align
= STACK_BOUNDARY
;
1266 extra_align
= BITS_PER_UNIT
;
1269 /* ??? STACK_POINTER_OFFSET is always defined now. */
1270 #if defined (STACK_DYNAMIC_OFFSET) || defined (STACK_POINTER_OFFSET)
1272 extra_align
= BITS_PER_UNIT
;
1277 unsigned extra
= (required_align
- extra_align
) / BITS_PER_UNIT
;
1279 size
= plus_constant (Pmode
, size
, extra
);
1280 size
= force_operand (size
, NULL_RTX
);
1282 if (flag_stack_usage_info
)
1283 stack_usage_size
+= extra
;
1285 if (extra
&& size_align
> extra_align
)
1286 size_align
= extra_align
;
1289 /* Round the size to a multiple of the required stack alignment.
1290 Since the stack if presumed to be rounded before this allocation,
1291 this will maintain the required alignment.
1293 If the stack grows downward, we could save an insn by subtracting
1294 SIZE from the stack pointer and then aligning the stack pointer.
1295 The problem with this is that the stack pointer may be unaligned
1296 between the execution of the subtraction and alignment insns and
1297 some machines do not allow this. Even on those that do, some
1298 signal handlers malfunction if a signal should occur between those
1299 insns. Since this is an extremely rare event, we have no reliable
1300 way of knowing which systems have this problem. So we avoid even
1301 momentarily mis-aligning the stack. */
1302 if (size_align
% MAX_SUPPORTED_STACK_ALIGNMENT
!= 0)
1304 size
= round_push (size
);
1306 if (flag_stack_usage_info
)
1308 int align
= crtl
->preferred_stack_boundary
/ BITS_PER_UNIT
;
1309 stack_usage_size
= (stack_usage_size
+ align
- 1) / align
* align
;
1313 target
= gen_reg_rtx (Pmode
);
1315 /* The size is supposed to be fully adjusted at this point so record it
1316 if stack usage info is requested. */
1317 if (flag_stack_usage_info
)
1319 current_function_dynamic_stack_size
+= stack_usage_size
;
1321 /* ??? This is gross but the only safe stance in the absence
1322 of stack usage oriented flow analysis. */
1323 if (!cannot_accumulate
)
1324 current_function_has_unbounded_dynamic_stack_size
= 1;
1327 final_label
= NULL_RTX
;
1328 final_target
= NULL_RTX
;
1330 /* If we are splitting the stack, we need to ask the backend whether
1331 there is enough room on the current stack. If there isn't, or if
1332 the backend doesn't know how to tell is, then we need to call a
1333 function to allocate memory in some other way. This memory will
1334 be released when we release the current stack segment. The
1335 effect is that stack allocation becomes less efficient, but at
1336 least it doesn't cause a stack overflow. */
1337 if (flag_split_stack
)
1339 rtx available_label
, ask
, space
, func
;
1341 available_label
= NULL_RTX
;
1343 #ifdef HAVE_split_stack_space_check
1344 if (HAVE_split_stack_space_check
)
1346 available_label
= gen_label_rtx ();
1348 /* This instruction will branch to AVAILABLE_LABEL if there
1349 are SIZE bytes available on the stack. */
1350 emit_insn (gen_split_stack_space_check (size
, available_label
));
1354 /* The __morestack_allocate_stack_space function will allocate
1355 memory using malloc. If the alignment of the memory returned
1356 by malloc does not meet REQUIRED_ALIGN, we increase SIZE to
1357 make sure we allocate enough space. */
1358 if (MALLOC_ABI_ALIGNMENT
>= required_align
)
1362 ask
= expand_binop (Pmode
, add_optab
, size
,
1363 GEN_INT (required_align
/ BITS_PER_UNIT
- 1),
1364 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1368 func
= init_one_libfunc ("__morestack_allocate_stack_space");
1370 space
= emit_library_call_value (func
, target
, LCT_NORMAL
, Pmode
,
1373 if (available_label
== NULL_RTX
)
1376 final_target
= gen_reg_rtx (Pmode
);
1378 emit_move_insn (final_target
, space
);
1380 final_label
= gen_label_rtx ();
1381 emit_jump (final_label
);
1383 emit_label (available_label
);
1386 do_pending_stack_adjust ();
1388 /* We ought to be called always on the toplevel and stack ought to be aligned
1390 gcc_assert (!(stack_pointer_delta
1391 % (PREFERRED_STACK_BOUNDARY
/ BITS_PER_UNIT
)));
1393 /* If needed, check that we have the required amount of stack. Take into
1394 account what has already been checked. */
1395 if (STACK_CHECK_MOVING_SP
)
1397 else if (flag_stack_check
== GENERIC_STACK_CHECK
)
1398 probe_stack_range (STACK_OLD_CHECK_PROTECT
+ STACK_CHECK_MAX_FRAME_SIZE
,
1400 else if (flag_stack_check
== STATIC_BUILTIN_STACK_CHECK
)
1401 probe_stack_range (STACK_CHECK_PROTECT
, size
);
1403 /* Don't let anti_adjust_stack emit notes. */
1404 suppress_reg_args_size
= true;
1406 /* Perform the required allocation from the stack. Some systems do
1407 this differently than simply incrementing/decrementing from the
1408 stack pointer, such as acquiring the space by calling malloc(). */
1409 #ifdef HAVE_allocate_stack
1410 if (HAVE_allocate_stack
)
1412 struct expand_operand ops
[2];
1413 /* We don't have to check against the predicate for operand 0 since
1414 TARGET is known to be a pseudo of the proper mode, which must
1415 be valid for the operand. */
1416 create_fixed_operand (&ops
[0], target
);
1417 create_convert_operand_to (&ops
[1], size
, STACK_SIZE_MODE
, true);
1418 expand_insn (CODE_FOR_allocate_stack
, 2, ops
);
1423 int saved_stack_pointer_delta
;
1425 #ifndef STACK_GROWS_DOWNWARD
1426 emit_move_insn (target
, virtual_stack_dynamic_rtx
);
1429 /* Check stack bounds if necessary. */
1430 if (crtl
->limit_stack
)
1433 rtx space_available
= gen_label_rtx ();
1434 #ifdef STACK_GROWS_DOWNWARD
1435 available
= expand_binop (Pmode
, sub_optab
,
1436 stack_pointer_rtx
, stack_limit_rtx
,
1437 NULL_RTX
, 1, OPTAB_WIDEN
);
1439 available
= expand_binop (Pmode
, sub_optab
,
1440 stack_limit_rtx
, stack_pointer_rtx
,
1441 NULL_RTX
, 1, OPTAB_WIDEN
);
1443 emit_cmp_and_jump_insns (available
, size
, GEU
, NULL_RTX
, Pmode
, 1,
1447 emit_insn (gen_trap ());
1450 error ("stack limits not supported on this target");
1452 emit_label (space_available
);
1455 saved_stack_pointer_delta
= stack_pointer_delta
;
1457 if (flag_stack_check
&& STACK_CHECK_MOVING_SP
)
1458 anti_adjust_stack_and_probe (size
, false);
1460 anti_adjust_stack (size
);
1462 /* Even if size is constant, don't modify stack_pointer_delta.
1463 The constant size alloca should preserve
1464 crtl->preferred_stack_boundary alignment. */
1465 stack_pointer_delta
= saved_stack_pointer_delta
;
1467 #ifdef STACK_GROWS_DOWNWARD
1468 emit_move_insn (target
, virtual_stack_dynamic_rtx
);
1472 suppress_reg_args_size
= false;
1474 /* Finish up the split stack handling. */
1475 if (final_label
!= NULL_RTX
)
1477 gcc_assert (flag_split_stack
);
1478 emit_move_insn (final_target
, target
);
1479 emit_label (final_label
);
1480 target
= final_target
;
1485 /* CEIL_DIV_EXPR needs to worry about the addition overflowing,
1486 but we know it can't. So add ourselves and then do
1488 target
= expand_binop (Pmode
, add_optab
, target
,
1489 GEN_INT (required_align
/ BITS_PER_UNIT
- 1),
1490 NULL_RTX
, 1, OPTAB_LIB_WIDEN
);
1491 target
= expand_divmod (0, TRUNC_DIV_EXPR
, Pmode
, target
,
1492 GEN_INT (required_align
/ BITS_PER_UNIT
),
1494 target
= expand_mult (Pmode
, target
,
1495 GEN_INT (required_align
/ BITS_PER_UNIT
),
1499 /* Now that we've committed to a return value, mark its alignment. */
1500 mark_reg_pointer (target
, required_align
);
1502 /* Record the new stack level for nonlocal gotos. */
1503 if (cfun
->nonlocal_goto_save_area
!= 0)
1504 update_nonlocal_goto_save_area ();
1509 /* A front end may want to override GCC's stack checking by providing a
1510 run-time routine to call to check the stack, so provide a mechanism for
1511 calling that routine. */
1513 static GTY(()) rtx stack_check_libfunc
;
1516 set_stack_check_libfunc (const char *libfunc_name
)
1518 gcc_assert (stack_check_libfunc
== NULL_RTX
);
1519 stack_check_libfunc
= gen_rtx_SYMBOL_REF (Pmode
, libfunc_name
);
1522 /* Emit one stack probe at ADDRESS, an address within the stack. */
1525 emit_stack_probe (rtx address
)
1527 #ifdef HAVE_probe_stack_address
1528 if (HAVE_probe_stack_address
)
1529 emit_insn (gen_probe_stack_address (address
));
1533 rtx memref
= gen_rtx_MEM (word_mode
, address
);
1535 MEM_VOLATILE_P (memref
) = 1;
1537 /* See if we have an insn to probe the stack. */
1538 #ifdef HAVE_probe_stack
1539 if (HAVE_probe_stack
)
1540 emit_insn (gen_probe_stack (memref
));
1543 emit_move_insn (memref
, const0_rtx
);
1547 /* Probe a range of stack addresses from FIRST to FIRST+SIZE, inclusive.
1548 FIRST is a constant and size is a Pmode RTX. These are offsets from
1549 the current stack pointer. STACK_GROWS_DOWNWARD says whether to add
1550 or subtract them from the stack pointer. */
1552 #define PROBE_INTERVAL (1 << STACK_CHECK_PROBE_INTERVAL_EXP)
1554 #ifdef STACK_GROWS_DOWNWARD
1555 #define STACK_GROW_OP MINUS
1556 #define STACK_GROW_OPTAB sub_optab
1557 #define STACK_GROW_OFF(off) -(off)
1559 #define STACK_GROW_OP PLUS
1560 #define STACK_GROW_OPTAB add_optab
1561 #define STACK_GROW_OFF(off) (off)
1565 probe_stack_range (HOST_WIDE_INT first
, rtx size
)
1567 /* First ensure SIZE is Pmode. */
1568 if (GET_MODE (size
) != VOIDmode
&& GET_MODE (size
) != Pmode
)
1569 size
= convert_to_mode (Pmode
, size
, 1);
1571 /* Next see if we have a function to check the stack. */
1572 if (stack_check_libfunc
)
1574 rtx addr
= memory_address (Pmode
,
1575 gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1577 plus_constant (Pmode
,
1579 emit_library_call (stack_check_libfunc
, LCT_NORMAL
, VOIDmode
, 1, addr
,
1583 /* Next see if we have an insn to check the stack. */
1584 #ifdef HAVE_check_stack
1585 else if (HAVE_check_stack
)
1587 struct expand_operand ops
[1];
1588 rtx addr
= memory_address (Pmode
,
1589 gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1591 plus_constant (Pmode
,
1594 create_input_operand (&ops
[0], addr
, Pmode
);
1595 success
= maybe_expand_insn (CODE_FOR_check_stack
, 1, ops
);
1596 gcc_assert (success
);
1600 /* Otherwise we have to generate explicit probes. If we have a constant
1601 small number of them to generate, that's the easy case. */
1602 else if (CONST_INT_P (size
) && INTVAL (size
) < 7 * PROBE_INTERVAL
)
1604 HOST_WIDE_INT isize
= INTVAL (size
), i
;
1607 /* Probe at FIRST + N * PROBE_INTERVAL for values of N from 1 until
1608 it exceeds SIZE. If only one probe is needed, this will not
1609 generate any code. Then probe at FIRST + SIZE. */
1610 for (i
= PROBE_INTERVAL
; i
< isize
; i
+= PROBE_INTERVAL
)
1612 addr
= memory_address (Pmode
,
1613 plus_constant (Pmode
, stack_pointer_rtx
,
1614 STACK_GROW_OFF (first
+ i
)));
1615 emit_stack_probe (addr
);
1618 addr
= memory_address (Pmode
,
1619 plus_constant (Pmode
, stack_pointer_rtx
,
1620 STACK_GROW_OFF (first
+ isize
)));
1621 emit_stack_probe (addr
);
1624 /* In the variable case, do the same as above, but in a loop. Note that we
1625 must be extra careful with variables wrapping around because we might be
1626 at the very top (or the very bottom) of the address space and we have to
1627 be able to handle this case properly; in particular, we use an equality
1628 test for the loop condition. */
1631 rtx rounded_size
, rounded_size_op
, test_addr
, last_addr
, temp
;
1632 rtx loop_lab
= gen_label_rtx ();
1633 rtx end_lab
= gen_label_rtx ();
1636 /* Step 1: round SIZE to the previous multiple of the interval. */
1638 /* ROUNDED_SIZE = SIZE & -PROBE_INTERVAL */
1640 = simplify_gen_binary (AND
, Pmode
, size
, GEN_INT (-PROBE_INTERVAL
));
1641 rounded_size_op
= force_operand (rounded_size
, NULL_RTX
);
1644 /* Step 2: compute initial and final value of the loop counter. */
1646 /* TEST_ADDR = SP + FIRST. */
1647 test_addr
= force_operand (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1649 GEN_INT (first
)), NULL_RTX
);
1651 /* LAST_ADDR = SP + FIRST + ROUNDED_SIZE. */
1652 last_addr
= force_operand (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1654 rounded_size_op
), NULL_RTX
);
1659 while (TEST_ADDR != LAST_ADDR)
1661 TEST_ADDR = TEST_ADDR + PROBE_INTERVAL
1665 probes at FIRST + N * PROBE_INTERVAL for values of N from 1
1666 until it is equal to ROUNDED_SIZE. */
1668 emit_label (loop_lab
);
1670 /* Jump to END_LAB if TEST_ADDR == LAST_ADDR. */
1671 emit_cmp_and_jump_insns (test_addr
, last_addr
, EQ
, NULL_RTX
, Pmode
, 1,
1674 /* TEST_ADDR = TEST_ADDR + PROBE_INTERVAL. */
1675 temp
= expand_binop (Pmode
, STACK_GROW_OPTAB
, test_addr
,
1676 GEN_INT (PROBE_INTERVAL
), test_addr
,
1679 gcc_assert (temp
== test_addr
);
1681 /* Probe at TEST_ADDR. */
1682 emit_stack_probe (test_addr
);
1684 emit_jump (loop_lab
);
1686 emit_label (end_lab
);
1689 /* Step 4: probe at FIRST + SIZE if we cannot assert at compile-time
1690 that SIZE is equal to ROUNDED_SIZE. */
1692 /* TEMP = SIZE - ROUNDED_SIZE. */
1693 temp
= simplify_gen_binary (MINUS
, Pmode
, size
, rounded_size
);
1694 if (temp
!= const0_rtx
)
1698 if (CONST_INT_P (temp
))
1700 /* Use [base + disp} addressing mode if supported. */
1701 HOST_WIDE_INT offset
= INTVAL (temp
);
1702 addr
= memory_address (Pmode
,
1703 plus_constant (Pmode
, last_addr
,
1704 STACK_GROW_OFF (offset
)));
1708 /* Manual CSE if the difference is not known at compile-time. */
1709 temp
= gen_rtx_MINUS (Pmode
, size
, rounded_size_op
);
1710 addr
= memory_address (Pmode
,
1711 gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1715 emit_stack_probe (addr
);
1720 /* Adjust the stack pointer by minus SIZE (an rtx for a number of bytes)
1721 while probing it. This pushes when SIZE is positive. SIZE need not
1722 be constant. If ADJUST_BACK is true, adjust back the stack pointer
1723 by plus SIZE at the end. */
1726 anti_adjust_stack_and_probe (rtx size
, bool adjust_back
)
1728 /* We skip the probe for the first interval + a small dope of 4 words and
1729 probe that many bytes past the specified size to maintain a protection
1730 area at the botton of the stack. */
1731 const int dope
= 4 * UNITS_PER_WORD
;
1733 /* First ensure SIZE is Pmode. */
1734 if (GET_MODE (size
) != VOIDmode
&& GET_MODE (size
) != Pmode
)
1735 size
= convert_to_mode (Pmode
, size
, 1);
1737 /* If we have a constant small number of probes to generate, that's the
1739 if (CONST_INT_P (size
) && INTVAL (size
) < 7 * PROBE_INTERVAL
)
1741 HOST_WIDE_INT isize
= INTVAL (size
), i
;
1742 bool first_probe
= true;
1744 /* Adjust SP and probe at PROBE_INTERVAL + N * PROBE_INTERVAL for
1745 values of N from 1 until it exceeds SIZE. If only one probe is
1746 needed, this will not generate any code. Then adjust and probe
1747 to PROBE_INTERVAL + SIZE. */
1748 for (i
= PROBE_INTERVAL
; i
< isize
; i
+= PROBE_INTERVAL
)
1752 anti_adjust_stack (GEN_INT (2 * PROBE_INTERVAL
+ dope
));
1753 first_probe
= false;
1756 anti_adjust_stack (GEN_INT (PROBE_INTERVAL
));
1757 emit_stack_probe (stack_pointer_rtx
);
1761 anti_adjust_stack (plus_constant (Pmode
, size
, PROBE_INTERVAL
+ dope
));
1763 anti_adjust_stack (plus_constant (Pmode
, size
, PROBE_INTERVAL
- i
));
1764 emit_stack_probe (stack_pointer_rtx
);
1767 /* In the variable case, do the same as above, but in a loop. Note that we
1768 must be extra careful with variables wrapping around because we might be
1769 at the very top (or the very bottom) of the address space and we have to
1770 be able to handle this case properly; in particular, we use an equality
1771 test for the loop condition. */
1774 rtx rounded_size
, rounded_size_op
, last_addr
, temp
;
1775 rtx loop_lab
= gen_label_rtx ();
1776 rtx end_lab
= gen_label_rtx ();
1779 /* Step 1: round SIZE to the previous multiple of the interval. */
1781 /* ROUNDED_SIZE = SIZE & -PROBE_INTERVAL */
1783 = simplify_gen_binary (AND
, Pmode
, size
, GEN_INT (-PROBE_INTERVAL
));
1784 rounded_size_op
= force_operand (rounded_size
, NULL_RTX
);
1787 /* Step 2: compute initial and final value of the loop counter. */
1789 /* SP = SP_0 + PROBE_INTERVAL. */
1790 anti_adjust_stack (GEN_INT (PROBE_INTERVAL
+ dope
));
1792 /* LAST_ADDR = SP_0 + PROBE_INTERVAL + ROUNDED_SIZE. */
1793 last_addr
= force_operand (gen_rtx_fmt_ee (STACK_GROW_OP
, Pmode
,
1795 rounded_size_op
), NULL_RTX
);
1800 while (SP != LAST_ADDR)
1802 SP = SP + PROBE_INTERVAL
1806 adjusts SP and probes at PROBE_INTERVAL + N * PROBE_INTERVAL for
1807 values of N from 1 until it is equal to ROUNDED_SIZE. */
1809 emit_label (loop_lab
);
1811 /* Jump to END_LAB if SP == LAST_ADDR. */
1812 emit_cmp_and_jump_insns (stack_pointer_rtx
, last_addr
, EQ
, NULL_RTX
,
1815 /* SP = SP + PROBE_INTERVAL and probe at SP. */
1816 anti_adjust_stack (GEN_INT (PROBE_INTERVAL
));
1817 emit_stack_probe (stack_pointer_rtx
);
1819 emit_jump (loop_lab
);
1821 emit_label (end_lab
);
1824 /* Step 4: adjust SP and probe at PROBE_INTERVAL + SIZE if we cannot
1825 assert at compile-time that SIZE is equal to ROUNDED_SIZE. */
1827 /* TEMP = SIZE - ROUNDED_SIZE. */
1828 temp
= simplify_gen_binary (MINUS
, Pmode
, size
, rounded_size
);
1829 if (temp
!= const0_rtx
)
1831 /* Manual CSE if the difference is not known at compile-time. */
1832 if (GET_CODE (temp
) != CONST_INT
)
1833 temp
= gen_rtx_MINUS (Pmode
, size
, rounded_size_op
);
1834 anti_adjust_stack (temp
);
1835 emit_stack_probe (stack_pointer_rtx
);
1839 /* Adjust back and account for the additional first interval. */
1841 adjust_stack (plus_constant (Pmode
, size
, PROBE_INTERVAL
+ dope
));
1843 adjust_stack (GEN_INT (PROBE_INTERVAL
+ dope
));
1846 /* Return an rtx representing the register or memory location
1847 in which a scalar value of data type VALTYPE
1848 was returned by a function call to function FUNC.
1849 FUNC is a FUNCTION_DECL, FNTYPE a FUNCTION_TYPE node if the precise
1850 function is known, otherwise 0.
1851 OUTGOING is 1 if on a machine with register windows this function
1852 should return the register in which the function will put its result
1856 hard_function_value (const_tree valtype
, const_tree func
, const_tree fntype
,
1857 int outgoing ATTRIBUTE_UNUSED
)
1861 val
= targetm
.calls
.function_value (valtype
, func
? func
: fntype
, outgoing
);
1864 && GET_MODE (val
) == BLKmode
)
1866 unsigned HOST_WIDE_INT bytes
= int_size_in_bytes (valtype
);
1867 enum machine_mode tmpmode
;
1869 /* int_size_in_bytes can return -1. We don't need a check here
1870 since the value of bytes will then be large enough that no
1871 mode will match anyway. */
1873 for (tmpmode
= GET_CLASS_NARROWEST_MODE (MODE_INT
);
1874 tmpmode
!= VOIDmode
;
1875 tmpmode
= GET_MODE_WIDER_MODE (tmpmode
))
1877 /* Have we found a large enough mode? */
1878 if (GET_MODE_SIZE (tmpmode
) >= bytes
)
1882 /* No suitable mode found. */
1883 gcc_assert (tmpmode
!= VOIDmode
);
1885 PUT_MODE (val
, tmpmode
);
1890 /* Return an rtx representing the register or memory location
1891 in which a scalar value of mode MODE was returned by a library call. */
1894 hard_libcall_value (enum machine_mode mode
, rtx fun
)
1896 return targetm
.calls
.libcall_value (mode
, fun
);
1899 /* Look up the tree code for a given rtx code
1900 to provide the arithmetic operation for REAL_ARITHMETIC.
1901 The function returns an int because the caller may not know
1902 what `enum tree_code' means. */
1905 rtx_to_tree_code (enum rtx_code code
)
1907 enum tree_code tcode
;
1930 tcode
= LAST_AND_UNUSED_TREE_CODE
;
1933 return ((int) tcode
);
1936 #include "gt-explow.h"