2012-01-31 Paul Thomas <pault@gcc.gnu.org>
[official-gcc.git] / gcc / tree-ssa-address.c
blobcf131578d2d7cd538123e04917fc8d2032ad6559
1 /* Memory address lowering and addressing mode selection.
2 Copyright (C) 2004, 2006, 2007, 2008, 2009, 2010, 2011
3 Free Software Foundation, Inc.
5 This file is part of GCC.
7 GCC is free software; you can redistribute it and/or modify it
8 under the terms of the GNU General Public License as published by the
9 Free Software Foundation; either version 3, or (at your option) any
10 later version.
12 GCC is distributed in the hope that it will be useful, but WITHOUT
13 ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
15 for more details.
17 You should have received a copy of the GNU General Public License
18 along with GCC; see the file COPYING3. If not see
19 <http://www.gnu.org/licenses/>. */
21 /* Utility functions for manipulation with TARGET_MEM_REFs -- tree expressions
22 that directly map to addressing modes of the target. */
24 #include "config.h"
25 #include "system.h"
26 #include "coretypes.h"
27 #include "tm.h"
28 #include "tree.h"
29 #include "tm_p.h"
30 #include "basic-block.h"
31 #include "output.h"
32 #include "tree-pretty-print.h"
33 #include "tree-flow.h"
34 #include "tree-dump.h"
35 #include "tree-pass.h"
36 #include "timevar.h"
37 #include "flags.h"
38 #include "tree-inline.h"
39 #include "tree-affine.h"
41 /* FIXME: We compute address costs using RTL. */
42 #include "insn-config.h"
43 #include "rtl.h"
44 #include "recog.h"
45 #include "expr.h"
46 #include "ggc.h"
47 #include "target.h"
49 /* TODO -- handling of symbols (according to Richard Hendersons
50 comments, http://gcc.gnu.org/ml/gcc-patches/2005-04/msg00949.html):
52 There are at least 5 different kinds of symbols that we can run up against:
54 (1) binds_local_p, small data area.
55 (2) binds_local_p, eg local statics
56 (3) !binds_local_p, eg global variables
57 (4) thread local, local_exec
58 (5) thread local, !local_exec
60 Now, (1) won't appear often in an array context, but it certainly can.
61 All you have to do is set -GN high enough, or explicitly mark any
62 random object __attribute__((section (".sdata"))).
64 All of these affect whether or not a symbol is in fact a valid address.
65 The only one tested here is (3). And that result may very well
66 be incorrect for (4) or (5).
68 An incorrect result here does not cause incorrect results out the
69 back end, because the expander in expr.c validizes the address. However
70 it would be nice to improve the handling here in order to produce more
71 precise results. */
73 /* A "template" for memory address, used to determine whether the address is
74 valid for mode. */
76 typedef struct GTY (()) mem_addr_template {
77 rtx ref; /* The template. */
78 rtx * GTY ((skip)) step_p; /* The point in template where the step should be
79 filled in. */
80 rtx * GTY ((skip)) off_p; /* The point in template where the offset should
81 be filled in. */
82 } mem_addr_template;
84 DEF_VEC_O (mem_addr_template);
85 DEF_VEC_ALLOC_O (mem_addr_template, gc);
87 /* The templates. Each of the low five bits of the index corresponds to one
88 component of TARGET_MEM_REF being present, while the high bits identify
89 the address space. See TEMPL_IDX. */
91 static GTY(()) VEC (mem_addr_template, gc) *mem_addr_template_list;
93 #define TEMPL_IDX(AS, SYMBOL, BASE, INDEX, STEP, OFFSET) \
94 (((int) (AS) << 5) \
95 | ((SYMBOL != 0) << 4) \
96 | ((BASE != 0) << 3) \
97 | ((INDEX != 0) << 2) \
98 | ((STEP != 0) << 1) \
99 | (OFFSET != 0))
101 /* Stores address for memory reference with parameters SYMBOL, BASE, INDEX,
102 STEP and OFFSET to *ADDR using address mode ADDRESS_MODE. Stores pointers
103 to where step is placed to *STEP_P and offset to *OFFSET_P. */
105 static void
106 gen_addr_rtx (enum machine_mode address_mode,
107 rtx symbol, rtx base, rtx index, rtx step, rtx offset,
108 rtx *addr, rtx **step_p, rtx **offset_p)
110 rtx act_elem;
112 *addr = NULL_RTX;
113 if (step_p)
114 *step_p = NULL;
115 if (offset_p)
116 *offset_p = NULL;
118 if (index)
120 act_elem = index;
121 if (step)
123 act_elem = gen_rtx_MULT (address_mode, act_elem, step);
125 if (step_p)
126 *step_p = &XEXP (act_elem, 1);
129 *addr = act_elem;
132 if (base && base != const0_rtx)
134 if (*addr)
135 *addr = simplify_gen_binary (PLUS, address_mode, base, *addr);
136 else
137 *addr = base;
140 if (symbol)
142 act_elem = symbol;
143 if (offset)
145 act_elem = gen_rtx_PLUS (address_mode, act_elem, offset);
147 if (offset_p)
148 *offset_p = &XEXP (act_elem, 1);
150 if (GET_CODE (symbol) == SYMBOL_REF
151 || GET_CODE (symbol) == LABEL_REF
152 || GET_CODE (symbol) == CONST)
153 act_elem = gen_rtx_CONST (address_mode, act_elem);
156 if (*addr)
157 *addr = gen_rtx_PLUS (address_mode, *addr, act_elem);
158 else
159 *addr = act_elem;
161 else if (offset)
163 if (*addr)
165 *addr = gen_rtx_PLUS (address_mode, *addr, offset);
166 if (offset_p)
167 *offset_p = &XEXP (*addr, 1);
169 else
171 *addr = offset;
172 if (offset_p)
173 *offset_p = addr;
177 if (!*addr)
178 *addr = const0_rtx;
181 /* Returns address for TARGET_MEM_REF with parameters given by ADDR
182 in address space AS.
183 If REALLY_EXPAND is false, just make fake registers instead
184 of really expanding the operands, and perform the expansion in-place
185 by using one of the "templates". */
188 addr_for_mem_ref (struct mem_address *addr, addr_space_t as,
189 bool really_expand)
191 enum machine_mode address_mode = targetm.addr_space.address_mode (as);
192 enum machine_mode pointer_mode = targetm.addr_space.pointer_mode (as);
193 rtx address, sym, bse, idx, st, off;
194 struct mem_addr_template *templ;
196 if (addr->step && !integer_onep (addr->step))
197 st = immed_double_int_const (tree_to_double_int (addr->step), pointer_mode);
198 else
199 st = NULL_RTX;
201 if (addr->offset && !integer_zerop (addr->offset))
202 off = immed_double_int_const
203 (double_int_sext (tree_to_double_int (addr->offset),
204 TYPE_PRECISION (TREE_TYPE (addr->offset))),
205 pointer_mode);
206 else
207 off = NULL_RTX;
209 if (!really_expand)
211 unsigned int templ_index
212 = TEMPL_IDX (as, addr->symbol, addr->base, addr->index, st, off);
214 if (templ_index
215 >= VEC_length (mem_addr_template, mem_addr_template_list))
216 VEC_safe_grow_cleared (mem_addr_template, gc, mem_addr_template_list,
217 templ_index + 1);
219 /* Reuse the templates for addresses, so that we do not waste memory. */
220 templ = VEC_index (mem_addr_template, mem_addr_template_list, templ_index);
221 if (!templ->ref)
223 sym = (addr->symbol ?
224 gen_rtx_SYMBOL_REF (pointer_mode, ggc_strdup ("test_symbol"))
225 : NULL_RTX);
226 bse = (addr->base ?
227 gen_raw_REG (pointer_mode, LAST_VIRTUAL_REGISTER + 1)
228 : NULL_RTX);
229 idx = (addr->index ?
230 gen_raw_REG (pointer_mode, LAST_VIRTUAL_REGISTER + 2)
231 : NULL_RTX);
233 gen_addr_rtx (pointer_mode, sym, bse, idx,
234 st? const0_rtx : NULL_RTX,
235 off? const0_rtx : NULL_RTX,
236 &templ->ref,
237 &templ->step_p,
238 &templ->off_p);
241 if (st)
242 *templ->step_p = st;
243 if (off)
244 *templ->off_p = off;
246 return templ->ref;
249 /* Otherwise really expand the expressions. */
250 sym = (addr->symbol
251 ? expand_expr (addr->symbol, NULL_RTX, pointer_mode, EXPAND_NORMAL)
252 : NULL_RTX);
253 bse = (addr->base
254 ? expand_expr (addr->base, NULL_RTX, pointer_mode, EXPAND_NORMAL)
255 : NULL_RTX);
256 idx = (addr->index
257 ? expand_expr (addr->index, NULL_RTX, pointer_mode, EXPAND_NORMAL)
258 : NULL_RTX);
260 gen_addr_rtx (pointer_mode, sym, bse, idx, st, off, &address, NULL, NULL);
261 if (pointer_mode != address_mode)
262 address = convert_memory_address (address_mode, address);
263 return address;
266 /* Returns address of MEM_REF in TYPE. */
268 tree
269 tree_mem_ref_addr (tree type, tree mem_ref)
271 tree addr;
272 tree act_elem;
273 tree step = TMR_STEP (mem_ref), offset = TMR_OFFSET (mem_ref);
274 tree addr_base = NULL_TREE, addr_off = NULL_TREE;
276 addr_base = fold_convert (type, TMR_BASE (mem_ref));
278 act_elem = TMR_INDEX (mem_ref);
279 if (act_elem)
281 if (step)
282 act_elem = fold_build2 (MULT_EXPR, TREE_TYPE (act_elem),
283 act_elem, step);
284 addr_off = act_elem;
287 act_elem = TMR_INDEX2 (mem_ref);
288 if (act_elem)
290 if (addr_off)
291 addr_off = fold_build2 (PLUS_EXPR, TREE_TYPE (addr_off),
292 addr_off, act_elem);
293 else
294 addr_off = act_elem;
297 if (offset && !integer_zerop (offset))
299 if (addr_off)
300 addr_off = fold_build2 (PLUS_EXPR, TREE_TYPE (addr_off), addr_off,
301 fold_convert (TREE_TYPE (addr_off), offset));
302 else
303 addr_off = offset;
306 if (addr_off)
307 addr = fold_build_pointer_plus (addr_base, addr_off);
308 else
309 addr = addr_base;
311 return addr;
314 /* Returns true if a memory reference in MODE and with parameters given by
315 ADDR is valid on the current target. */
317 static bool
318 valid_mem_ref_p (enum machine_mode mode, addr_space_t as,
319 struct mem_address *addr)
321 rtx address;
323 address = addr_for_mem_ref (addr, as, false);
324 if (!address)
325 return false;
327 return memory_address_addr_space_p (mode, address, as);
330 /* Checks whether a TARGET_MEM_REF with type TYPE and parameters given by ADDR
331 is valid on the current target and if so, creates and returns the
332 TARGET_MEM_REF. If VERIFY is false omit the verification step. */
334 static tree
335 create_mem_ref_raw (tree type, tree alias_ptr_type, struct mem_address *addr,
336 bool verify)
338 tree base, index2;
340 if (verify
341 && !valid_mem_ref_p (TYPE_MODE (type), TYPE_ADDR_SPACE (type), addr))
342 return NULL_TREE;
344 if (addr->step && integer_onep (addr->step))
345 addr->step = NULL_TREE;
347 if (addr->offset)
348 addr->offset = fold_convert (alias_ptr_type, addr->offset);
349 else
350 addr->offset = build_int_cst (alias_ptr_type, 0);
352 if (addr->symbol)
354 base = addr->symbol;
355 index2 = addr->base;
357 else if (addr->base
358 && POINTER_TYPE_P (TREE_TYPE (addr->base)))
360 base = addr->base;
361 index2 = NULL_TREE;
363 else
365 base = build_int_cst (ptr_type_node, 0);
366 index2 = addr->base;
369 /* If possible use a plain MEM_REF instead of a TARGET_MEM_REF.
370 ??? As IVOPTs does not follow restrictions to where the base
371 pointer may point to create a MEM_REF only if we know that
372 base is valid. */
373 if ((TREE_CODE (base) == ADDR_EXPR || TREE_CODE (base) == INTEGER_CST)
374 && (!index2 || integer_zerop (index2))
375 && (!addr->index || integer_zerop (addr->index)))
376 return fold_build2 (MEM_REF, type, base, addr->offset);
378 return build5 (TARGET_MEM_REF, type,
379 base, addr->offset, addr->index, addr->step, index2);
382 /* Returns true if OBJ is an object whose address is a link time constant. */
384 static bool
385 fixed_address_object_p (tree obj)
387 return (TREE_CODE (obj) == VAR_DECL
388 && (TREE_STATIC (obj)
389 || DECL_EXTERNAL (obj))
390 && ! DECL_DLLIMPORT_P (obj));
393 /* If ADDR contains an address of object that is a link time constant,
394 move it to PARTS->symbol. */
396 static void
397 move_fixed_address_to_symbol (struct mem_address *parts, aff_tree *addr)
399 unsigned i;
400 tree val = NULL_TREE;
402 for (i = 0; i < addr->n; i++)
404 if (!double_int_one_p (addr->elts[i].coef))
405 continue;
407 val = addr->elts[i].val;
408 if (TREE_CODE (val) == ADDR_EXPR
409 && fixed_address_object_p (TREE_OPERAND (val, 0)))
410 break;
413 if (i == addr->n)
414 return;
416 parts->symbol = val;
417 aff_combination_remove_elt (addr, i);
420 /* If ADDR contains an instance of BASE_HINT, move it to PARTS->base. */
422 static void
423 move_hint_to_base (tree type, struct mem_address *parts, tree base_hint,
424 aff_tree *addr)
426 unsigned i;
427 tree val = NULL_TREE;
428 int qual;
430 for (i = 0; i < addr->n; i++)
432 if (!double_int_one_p (addr->elts[i].coef))
433 continue;
435 val = addr->elts[i].val;
436 if (operand_equal_p (val, base_hint, 0))
437 break;
440 if (i == addr->n)
441 return;
443 /* Cast value to appropriate pointer type. We cannot use a pointer
444 to TYPE directly, as the back-end will assume registers of pointer
445 type are aligned, and just the base itself may not actually be.
446 We use void pointer to the type's address space instead. */
447 qual = ENCODE_QUAL_ADDR_SPACE (TYPE_ADDR_SPACE (type));
448 type = build_qualified_type (void_type_node, qual);
449 parts->base = fold_convert (build_pointer_type (type), val);
450 aff_combination_remove_elt (addr, i);
453 /* If ADDR contains an address of a dereferenced pointer, move it to
454 PARTS->base. */
456 static void
457 move_pointer_to_base (struct mem_address *parts, aff_tree *addr)
459 unsigned i;
460 tree val = NULL_TREE;
462 for (i = 0; i < addr->n; i++)
464 if (!double_int_one_p (addr->elts[i].coef))
465 continue;
467 val = addr->elts[i].val;
468 if (POINTER_TYPE_P (TREE_TYPE (val)))
469 break;
472 if (i == addr->n)
473 return;
475 parts->base = val;
476 aff_combination_remove_elt (addr, i);
479 /* Moves the loop variant part V in linear address ADDR to be the index
480 of PARTS. */
482 static void
483 move_variant_to_index (struct mem_address *parts, aff_tree *addr, tree v)
485 unsigned i;
486 tree val = NULL_TREE;
488 gcc_assert (!parts->index);
489 for (i = 0; i < addr->n; i++)
491 val = addr->elts[i].val;
492 if (operand_equal_p (val, v, 0))
493 break;
496 if (i == addr->n)
497 return;
499 parts->index = fold_convert (sizetype, val);
500 parts->step = double_int_to_tree (sizetype, addr->elts[i].coef);
501 aff_combination_remove_elt (addr, i);
504 /* Adds ELT to PARTS. */
506 static void
507 add_to_parts (struct mem_address *parts, tree elt)
509 tree type;
511 if (!parts->index)
513 parts->index = fold_convert (sizetype, elt);
514 return;
517 if (!parts->base)
519 parts->base = elt;
520 return;
523 /* Add ELT to base. */
524 type = TREE_TYPE (parts->base);
525 if (POINTER_TYPE_P (type))
526 parts->base = fold_build_pointer_plus (parts->base, elt);
527 else
528 parts->base = fold_build2 (PLUS_EXPR, type,
529 parts->base, elt);
532 /* Finds the most expensive multiplication in ADDR that can be
533 expressed in an addressing mode and move the corresponding
534 element(s) to PARTS. */
536 static void
537 most_expensive_mult_to_index (tree type, struct mem_address *parts,
538 aff_tree *addr, bool speed)
540 addr_space_t as = TYPE_ADDR_SPACE (type);
541 enum machine_mode address_mode = targetm.addr_space.address_mode (as);
542 HOST_WIDE_INT coef;
543 double_int best_mult, amult, amult_neg;
544 unsigned best_mult_cost = 0, acost;
545 tree mult_elt = NULL_TREE, elt;
546 unsigned i, j;
547 enum tree_code op_code;
549 best_mult = double_int_zero;
550 for (i = 0; i < addr->n; i++)
552 if (!double_int_fits_in_shwi_p (addr->elts[i].coef))
553 continue;
555 coef = double_int_to_shwi (addr->elts[i].coef);
556 if (coef == 1
557 || !multiplier_allowed_in_address_p (coef, TYPE_MODE (type), as))
558 continue;
560 acost = multiply_by_cost (coef, address_mode, speed);
562 if (acost > best_mult_cost)
564 best_mult_cost = acost;
565 best_mult = addr->elts[i].coef;
569 if (!best_mult_cost)
570 return;
572 /* Collect elements multiplied by best_mult. */
573 for (i = j = 0; i < addr->n; i++)
575 amult = addr->elts[i].coef;
576 amult_neg = double_int_ext_for_comb (double_int_neg (amult), addr);
578 if (double_int_equal_p (amult, best_mult))
579 op_code = PLUS_EXPR;
580 else if (double_int_equal_p (amult_neg, best_mult))
581 op_code = MINUS_EXPR;
582 else
584 addr->elts[j] = addr->elts[i];
585 j++;
586 continue;
589 elt = fold_convert (sizetype, addr->elts[i].val);
590 if (mult_elt)
591 mult_elt = fold_build2 (op_code, sizetype, mult_elt, elt);
592 else if (op_code == PLUS_EXPR)
593 mult_elt = elt;
594 else
595 mult_elt = fold_build1 (NEGATE_EXPR, sizetype, elt);
597 addr->n = j;
599 parts->index = mult_elt;
600 parts->step = double_int_to_tree (sizetype, best_mult);
603 /* Splits address ADDR for a memory access of type TYPE into PARTS.
604 If BASE_HINT is non-NULL, it specifies an SSA name to be used
605 preferentially as base of the reference, and IV_CAND is the selected
606 iv candidate used in ADDR.
608 TODO -- be more clever about the distribution of the elements of ADDR
609 to PARTS. Some architectures do not support anything but single
610 register in address, possibly with a small integer offset; while
611 create_mem_ref will simplify the address to an acceptable shape
612 later, it would be more efficient to know that asking for complicated
613 addressing modes is useless. */
615 static void
616 addr_to_parts (tree type, aff_tree *addr, tree iv_cand,
617 tree base_hint, struct mem_address *parts,
618 bool speed)
620 tree part;
621 unsigned i;
623 parts->symbol = NULL_TREE;
624 parts->base = NULL_TREE;
625 parts->index = NULL_TREE;
626 parts->step = NULL_TREE;
628 if (!double_int_zero_p (addr->offset))
629 parts->offset = double_int_to_tree (sizetype, addr->offset);
630 else
631 parts->offset = NULL_TREE;
633 /* Try to find a symbol. */
634 move_fixed_address_to_symbol (parts, addr);
636 /* No need to do address parts reassociation if the number of parts
637 is <= 2 -- in that case, no loop invariant code motion can be
638 exposed. */
640 if (!base_hint && (addr->n > 2))
641 move_variant_to_index (parts, addr, iv_cand);
643 /* First move the most expensive feasible multiplication
644 to index. */
645 if (!parts->index)
646 most_expensive_mult_to_index (type, parts, addr, speed);
648 /* Try to find a base of the reference. Since at the moment
649 there is no reliable way how to distinguish between pointer and its
650 offset, this is just a guess. */
651 if (!parts->symbol && base_hint)
652 move_hint_to_base (type, parts, base_hint, addr);
653 if (!parts->symbol && !parts->base)
654 move_pointer_to_base (parts, addr);
656 /* Then try to process the remaining elements. */
657 for (i = 0; i < addr->n; i++)
659 part = fold_convert (sizetype, addr->elts[i].val);
660 if (!double_int_one_p (addr->elts[i].coef))
661 part = fold_build2 (MULT_EXPR, sizetype, part,
662 double_int_to_tree (sizetype, addr->elts[i].coef));
663 add_to_parts (parts, part);
665 if (addr->rest)
666 add_to_parts (parts, fold_convert (sizetype, addr->rest));
669 /* Force the PARTS to register. */
671 static void
672 gimplify_mem_ref_parts (gimple_stmt_iterator *gsi, struct mem_address *parts)
674 if (parts->base)
675 parts->base = force_gimple_operand_gsi_1 (gsi, parts->base,
676 is_gimple_mem_ref_addr, NULL_TREE,
677 true, GSI_SAME_STMT);
678 if (parts->index)
679 parts->index = force_gimple_operand_gsi (gsi, parts->index,
680 true, NULL_TREE,
681 true, GSI_SAME_STMT);
684 /* Creates and returns a TARGET_MEM_REF for address ADDR. If necessary
685 computations are emitted in front of GSI. TYPE is the mode
686 of created memory reference. IV_CAND is the selected iv candidate in ADDR,
687 and BASE_HINT is non NULL if IV_CAND comes from a base address
688 object. */
690 tree
691 create_mem_ref (gimple_stmt_iterator *gsi, tree type, aff_tree *addr,
692 tree alias_ptr_type, tree iv_cand, tree base_hint, bool speed)
694 tree mem_ref, tmp;
695 struct mem_address parts;
697 addr_to_parts (type, addr, iv_cand, base_hint, &parts, speed);
698 gimplify_mem_ref_parts (gsi, &parts);
699 mem_ref = create_mem_ref_raw (type, alias_ptr_type, &parts, true);
700 if (mem_ref)
701 return mem_ref;
703 /* The expression is too complicated. Try making it simpler. */
705 if (parts.step && !integer_onep (parts.step))
707 /* Move the multiplication to index. */
708 gcc_assert (parts.index);
709 parts.index = force_gimple_operand_gsi (gsi,
710 fold_build2 (MULT_EXPR, sizetype,
711 parts.index, parts.step),
712 true, NULL_TREE, true, GSI_SAME_STMT);
713 parts.step = NULL_TREE;
715 mem_ref = create_mem_ref_raw (type, alias_ptr_type, &parts, true);
716 if (mem_ref)
717 return mem_ref;
720 if (parts.symbol)
722 tmp = parts.symbol;
723 gcc_assert (is_gimple_val (tmp));
725 /* Add the symbol to base, eventually forcing it to register. */
726 if (parts.base)
728 gcc_assert (useless_type_conversion_p
729 (sizetype, TREE_TYPE (parts.base)));
731 if (parts.index)
733 parts.base = force_gimple_operand_gsi_1 (gsi,
734 fold_build_pointer_plus (tmp, parts.base),
735 is_gimple_mem_ref_addr, NULL_TREE, true, GSI_SAME_STMT);
737 else
739 parts.index = parts.base;
740 parts.base = tmp;
743 else
744 parts.base = tmp;
745 parts.symbol = NULL_TREE;
747 mem_ref = create_mem_ref_raw (type, alias_ptr_type, &parts, true);
748 if (mem_ref)
749 return mem_ref;
752 if (parts.index)
754 /* Add index to base. */
755 if (parts.base)
757 parts.base = force_gimple_operand_gsi_1 (gsi,
758 fold_build_pointer_plus (parts.base, parts.index),
759 is_gimple_mem_ref_addr, NULL_TREE, true, GSI_SAME_STMT);
761 else
762 parts.base = parts.index;
763 parts.index = NULL_TREE;
765 mem_ref = create_mem_ref_raw (type, alias_ptr_type, &parts, true);
766 if (mem_ref)
767 return mem_ref;
770 if (parts.offset && !integer_zerop (parts.offset))
772 /* Try adding offset to base. */
773 if (parts.base)
775 parts.base = force_gimple_operand_gsi_1 (gsi,
776 fold_build_pointer_plus (parts.base, parts.offset),
777 is_gimple_mem_ref_addr, NULL_TREE, true, GSI_SAME_STMT);
779 else
780 parts.base = parts.offset;
782 parts.offset = NULL_TREE;
784 mem_ref = create_mem_ref_raw (type, alias_ptr_type, &parts, true);
785 if (mem_ref)
786 return mem_ref;
789 /* Verify that the address is in the simplest possible shape
790 (only a register). If we cannot create such a memory reference,
791 something is really wrong. */
792 gcc_assert (parts.symbol == NULL_TREE);
793 gcc_assert (parts.index == NULL_TREE);
794 gcc_assert (!parts.step || integer_onep (parts.step));
795 gcc_assert (!parts.offset || integer_zerop (parts.offset));
796 gcc_unreachable ();
799 /* Copies components of the address from OP to ADDR. */
801 void
802 get_address_description (tree op, struct mem_address *addr)
804 if (TREE_CODE (TMR_BASE (op)) == ADDR_EXPR)
806 addr->symbol = TMR_BASE (op);
807 addr->base = TMR_INDEX2 (op);
809 else
811 addr->symbol = NULL_TREE;
812 if (TMR_INDEX2 (op))
814 gcc_assert (integer_zerop (TMR_BASE (op)));
815 addr->base = TMR_INDEX2 (op);
817 else
818 addr->base = TMR_BASE (op);
820 addr->index = TMR_INDEX (op);
821 addr->step = TMR_STEP (op);
822 addr->offset = TMR_OFFSET (op);
825 /* Copies the additional information attached to target_mem_ref FROM to TO. */
827 void
828 copy_mem_ref_info (tree to, tree from)
830 /* And the info about the original reference. */
831 TREE_SIDE_EFFECTS (to) = TREE_SIDE_EFFECTS (from);
832 TREE_THIS_VOLATILE (to) = TREE_THIS_VOLATILE (from);
835 /* Copies the reference information from OLD_REF to NEW_REF, where
836 NEW_REF should be either a MEM_REF or a TARGET_MEM_REF. */
838 void
839 copy_ref_info (tree new_ref, tree old_ref)
841 tree new_ptr_base = NULL_TREE;
843 gcc_assert (TREE_CODE (new_ref) == MEM_REF
844 || TREE_CODE (new_ref) == TARGET_MEM_REF);
846 TREE_SIDE_EFFECTS (new_ref) = TREE_SIDE_EFFECTS (old_ref);
847 TREE_THIS_VOLATILE (new_ref) = TREE_THIS_VOLATILE (old_ref);
849 new_ptr_base = TREE_OPERAND (new_ref, 0);
851 /* We can transfer points-to information from an old pointer
852 or decl base to the new one. */
853 if (new_ptr_base
854 && TREE_CODE (new_ptr_base) == SSA_NAME
855 && !SSA_NAME_PTR_INFO (new_ptr_base))
857 tree base = get_base_address (old_ref);
858 if (!base)
860 else if ((TREE_CODE (base) == MEM_REF
861 || TREE_CODE (base) == TARGET_MEM_REF)
862 && TREE_CODE (TREE_OPERAND (base, 0)) == SSA_NAME
863 && SSA_NAME_PTR_INFO (TREE_OPERAND (base, 0)))
865 struct ptr_info_def *new_pi;
866 duplicate_ssa_name_ptr_info
867 (new_ptr_base, SSA_NAME_PTR_INFO (TREE_OPERAND (base, 0)));
868 new_pi = SSA_NAME_PTR_INFO (new_ptr_base);
869 /* We have to be careful about transfering alignment information. */
870 if (TREE_CODE (old_ref) == MEM_REF
871 && !(TREE_CODE (new_ref) == TARGET_MEM_REF
872 && (TMR_INDEX2 (new_ref)
873 || (TMR_STEP (new_ref)
874 && (TREE_INT_CST_LOW (TMR_STEP (new_ref))
875 < new_pi->align)))))
877 new_pi->misalign += double_int_sub (mem_ref_offset (old_ref),
878 mem_ref_offset (new_ref)).low;
879 new_pi->misalign &= (new_pi->align - 1);
881 else
883 new_pi->align = 1;
884 new_pi->misalign = 0;
887 else if (TREE_CODE (base) == VAR_DECL
888 || TREE_CODE (base) == PARM_DECL
889 || TREE_CODE (base) == RESULT_DECL)
891 struct ptr_info_def *pi = get_ptr_info (new_ptr_base);
892 pt_solution_set_var (&pi->pt, base);
897 /* Move constants in target_mem_ref REF to offset. Returns the new target
898 mem ref if anything changes, NULL_TREE otherwise. */
900 tree
901 maybe_fold_tmr (tree ref)
903 struct mem_address addr;
904 bool changed = false;
905 tree ret, off;
907 get_address_description (ref, &addr);
909 if (addr.base
910 && TREE_CODE (addr.base) == INTEGER_CST
911 && !integer_zerop (addr.base))
913 addr.offset = fold_binary_to_constant (PLUS_EXPR,
914 TREE_TYPE (addr.offset),
915 addr.offset, addr.base);
916 addr.base = NULL_TREE;
917 changed = true;
920 if (addr.symbol
921 && TREE_CODE (TREE_OPERAND (addr.symbol, 0)) == MEM_REF)
923 addr.offset = fold_binary_to_constant
924 (PLUS_EXPR, TREE_TYPE (addr.offset),
925 addr.offset,
926 TREE_OPERAND (TREE_OPERAND (addr.symbol, 0), 1));
927 addr.symbol = TREE_OPERAND (TREE_OPERAND (addr.symbol, 0), 0);
928 changed = true;
930 else if (addr.symbol
931 && handled_component_p (TREE_OPERAND (addr.symbol, 0)))
933 HOST_WIDE_INT offset;
934 addr.symbol = build_fold_addr_expr
935 (get_addr_base_and_unit_offset
936 (TREE_OPERAND (addr.symbol, 0), &offset));
937 addr.offset = int_const_binop (PLUS_EXPR,
938 addr.offset, size_int (offset));
939 changed = true;
942 if (addr.index && TREE_CODE (addr.index) == INTEGER_CST)
944 off = addr.index;
945 if (addr.step)
947 off = fold_binary_to_constant (MULT_EXPR, sizetype,
948 off, addr.step);
949 addr.step = NULL_TREE;
952 addr.offset = fold_binary_to_constant (PLUS_EXPR,
953 TREE_TYPE (addr.offset),
954 addr.offset, off);
955 addr.index = NULL_TREE;
956 changed = true;
959 if (!changed)
960 return NULL_TREE;
962 /* If we have propagated something into this TARGET_MEM_REF and thus
963 ended up folding it, always create a new TARGET_MEM_REF regardless
964 if it is valid in this for on the target - the propagation result
965 wouldn't be anyway. */
966 ret = create_mem_ref_raw (TREE_TYPE (ref),
967 TREE_TYPE (addr.offset), &addr, false);
968 copy_mem_ref_info (ret, ref);
969 return ret;
972 /* Dump PARTS to FILE. */
974 extern void dump_mem_address (FILE *, struct mem_address *);
975 void
976 dump_mem_address (FILE *file, struct mem_address *parts)
978 if (parts->symbol)
980 fprintf (file, "symbol: ");
981 print_generic_expr (file, TREE_OPERAND (parts->symbol, 0), TDF_SLIM);
982 fprintf (file, "\n");
984 if (parts->base)
986 fprintf (file, "base: ");
987 print_generic_expr (file, parts->base, TDF_SLIM);
988 fprintf (file, "\n");
990 if (parts->index)
992 fprintf (file, "index: ");
993 print_generic_expr (file, parts->index, TDF_SLIM);
994 fprintf (file, "\n");
996 if (parts->step)
998 fprintf (file, "step: ");
999 print_generic_expr (file, parts->step, TDF_SLIM);
1000 fprintf (file, "\n");
1002 if (parts->offset)
1004 fprintf (file, "offset: ");
1005 print_generic_expr (file, parts->offset, TDF_SLIM);
1006 fprintf (file, "\n");
1010 #include "gt-tree-ssa-address.h"