2 * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @brief Memory disambiguator
23 * @author Michael Beck
34 #include "irgraph_t.h"
46 /** The debug handle. */
47 DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
49 /** The source language specific language disambiguator function. */
50 static DISAMBIGUATOR_FUNC language_disambuigator = NULL;
52 /** The global memory disambiguator options. */
53 static unsigned global_mem_disamgig_opt = aa_opt_no_opt;
55 /* Returns a human readable name for an alias relation. */
56 const char *get_ir_alias_relation_name(ir_alias_relation rel) {
57 #define X(a) case a: return #a
62 default: assert(0); return "UNKNOWN";
67 /* Get the memory disambiguator options for a graph. */
68 unsigned get_irg_memory_disambiguator_options(ir_graph *irg) {
69 unsigned opt = irg->mem_disambig_opt;
70 if (opt & aa_opt_inherited)
71 return global_mem_disamgig_opt;
73 } /* get_irg_memory_disambiguator_options */
75 /* Set the memory disambiguator options for a graph. */
76 void set_irg_memory_disambiguator_options(ir_graph *irg, unsigned options) {
77 irg->mem_disambig_opt = options & ~aa_opt_inherited;
78 } /* set_irg_memory_disambiguator_options */
80 /* Set the global disambiguator options for all graphs not having local options. */
81 void set_irp_memory_disambiguator_options(unsigned options) {
82 global_mem_disamgig_opt = options;
83 } /* set_irp_memory_disambiguator_options */
86 * Find the base address and entity of an Sel node.
89 * @param pEnt after return points to the base entity.
91 * @return the base address.
93 static ir_node *find_base_adr(ir_node *sel, ir_entity **pEnt) {
94 ir_node *ptr = get_Sel_ptr(sel);
98 ptr = get_Sel_ptr(sel);
100 *pEnt = get_Sel_entity(sel);
102 } /* find_base_adr */
105 * Check if a given Const node is greater or equal a given size.
107 * @return no_alias if the Const is greater, may_alias else
109 static ir_alias_relation check_const(ir_node *cns, int size) {
110 tarval *tv = get_Const_tarval(cns);
114 return tarval_is_null(tv) ? may_alias : no_alias;
115 tv_size = new_tarval_from_long(size, get_tarval_mode(tv));
116 return tarval_cmp(tv_size, tv) & (pn_Cmp_Eq|pn_Cmp_Lt) ? no_alias : may_alias;
120 * Treat idx1 and idx2 as integer indexes and check if they differ always more than size.
122 * @return sure_alias iff idx1 == idx2
123 * no_alias iff they ALWAYS differ more than size
126 static ir_alias_relation different_index(ir_node *idx1, ir_node *idx2, int size) {
129 if (is_Const(idx1) && is_Const(idx2)) {
130 /* both are const, we can compare them */
131 tarval *tv1 = get_Const_tarval(idx1);
132 tarval *tv2 = get_Const_tarval(idx2);
133 tarval *tv, *tv_size;
137 return tv1 == tv2 ? sure_alias : no_alias;
139 /* arg, modes may be different */
140 m1 = get_tarval_mode(tv1);
141 m2 = get_tarval_mode(tv2);
143 int size = get_mode_size_bits(m1) - get_mode_size_bits(m2);
146 /* m1 is a small mode, cast up */
147 m1 = mode_is_signed(m1) ? find_signed_mode(m2) : find_unsigned_mode(m2);
149 /* should NOT happen, but if it does we give up here */
152 tv1 = tarval_convert_to(tv1, m1);
153 } else if (size > 0) {
154 /* m2 is a small mode, cast up */
155 m2 = mode_is_signed(m2) ? find_signed_mode(m1) : find_unsigned_mode(m1);
157 /* should NOT happen, but if it does we give up here */
160 tv2 = tarval_convert_to(tv2, m2);
162 /* here the size should be identical, check for signed */
163 if (get_mode_sign(m1) != get_mode_sign(m2)) {
164 /* find the signed */
165 if (mode_is_signed(m2)) {
172 /* m1 is now the signed one */
173 if (tarval_cmp(tv1, get_tarval_null(m1)) & (pn_Cmp_Eq|pn_Cmp_Gt)) {
174 /* tv1 is signed, but >= 0, simply cast into unsigned */
175 tv1 = tarval_convert_to(tv1, m2);
177 tv_size = new_tarval_from_long(size, m2);
179 if (tarval_cmp(tv2, tv_size) & (pn_Cmp_Eq|pn_Cmp_Gt)) {
180 /* tv1 is negative and tv2 >= tv_size, so the difference is bigger than size */
183 /* tv_size > tv2, so we can subtract without overflow */
184 tv2 = tarval_sub(tv_size, tv2);
186 /* tv1 is < 0, so we can negate it */
187 tv1 = tarval_neg(tv1);
189 /* cast it into unsigned. for two-complement it does the right thing for MIN_INT */
190 tv1 = tarval_convert_to(tv1, m2);
192 /* now we can compare without overflow */
193 return tarval_cmp(tv1, tv2) & (pn_Cmp_Eq|pn_Cmp_Gt) ? no_alias : may_alias;
197 if (tarval_cmp(tv1, tv2) == pn_Cmp_Gt) {
202 /* tv1 is now the "smaller" one */
203 tv = tarval_sub(tv2, tv1);
204 tv_size = new_tarval_from_long(size, get_tarval_mode(tv));
205 return tarval_cmp(tv_size, tv) & (pn_Cmp_Eq|pn_Cmp_Lt) ? no_alias : may_alias;
208 /* Note: we rely here on the fact that normalization puts constants on the RIGHT side */
210 ir_node *l1 = get_Add_left(idx1);
211 ir_node *r1 = get_Add_right(idx1);
216 return check_const(r1, size);
219 /* both are Adds, check if they are of x + a == x + b kind */
220 ir_node *l2 = get_Add_left(idx2);
221 ir_node *r2 = get_Add_right(idx2);
224 return different_index(r1, r2, size);
226 return different_index(r1, l2, size);
228 return different_index(l1, l2, size);
230 return different_index(l1, r2, size);
234 ir_node *l2 = get_Add_left(idx2);
235 ir_node *r2 = get_Add_right(idx2);
240 return check_const(r2, size);
245 ir_node *l1 = get_Sub_left(idx1);
246 ir_node *r1 = get_Sub_right(idx1);
251 return check_const(r1, size);
255 /* both are Subs, check if they are of x - a == x - b kind */
256 ir_node *l2 = get_Sub_left(idx2);
259 ir_node *r2 = get_Sub_right(idx2);
260 return different_index(r1, r2, size);
265 ir_node *l2 = get_Sub_left(idx2);
266 ir_node *r2 = get_Sub_right(idx2);
271 return check_const(r2, size);
276 } /* different_index */
279 * Two Sel addresses have the same base address, check if there offsets are
282 * @param adr1 The first address.
283 * @param adr2 The second address.
285 static ir_alias_relation different_sel_offsets(ir_node *sel1, ir_node *sel2) {
286 /* seems to be broken */
290 ir_entity *ent1 = get_Sel_entity(sel1);
291 ir_entity *ent2 = get_Sel_entity(sel2);
292 int i, check_arr = 0;
297 ir_type *tp1 = get_entity_type(ent1);
298 ir_type *tp2 = get_entity_type(ent2);
302 else if (get_type_state(tp1) == layout_fixed && get_type_state(tp2) == layout_fixed &&
303 get_type_size_bits(tp1) == get_type_size_bits(tp2))
307 /* we select an entity of same size, check for indexes */
308 int n = get_Sel_n_indexs(sel1);
311 if (n > 0 && n == get_Sel_n_indexs(sel2)) {
312 /* same non-zero number of indexes, an array access, check */
313 for (i = 0; i < n; ++i) {
314 ir_node *idx1 = get_Sel_index(sel1, i);
315 ir_node *idx2 = get_Sel_index(sel2, i);
316 ir_alias_relation res = different_index(idx1, idx2, 0); /* we can safely IGNORE the size here if it's at least >0 */
318 if (res == may_alias)
320 else if (res == no_alias)
323 /* if we have at least one no_alias, there is no alias relation, else we have sure */
324 return have_no > 0 ? no_alias : sure_alias;
329 } /* different_sel_offsets */
332 * Determine the alias relation by checking if adr1 and adr2 are pointer
335 * @param adr1 The first address.
336 * @param adr2 The second address.
338 static ir_alias_relation different_types(ir_node *adr1, ir_node *adr2)
340 ir_entity *ent1 = NULL, *ent2 = NULL;
342 if (is_SymConst_addr_ent(adr1))
343 ent1 = get_SymConst_entity(adr1);
344 else if (is_Sel(adr1))
345 ent1 = get_Sel_entity(adr1);
347 if (is_SymConst_addr_ent(adr2))
348 ent2 = get_SymConst_entity(adr2);
349 else if (is_Sel(adr2))
350 ent2 = get_Sel_entity(adr2);
352 if (ent1 != NULL && ent2 != NULL) {
353 ir_type *tp1 = get_entity_type(ent1);
354 ir_type *tp2 = get_entity_type(ent2);
357 if (is_Pointer_type(tp1) && is_Pointer_type(tp2)) {
358 /* do deref until no pointer types are found */
360 tp1 = get_pointer_points_to_type(tp1);
361 tp2 = get_pointer_points_to_type(tp2);
362 } while (is_Pointer_type(tp1) && is_Pointer_type(tp2));
365 if (get_type_tpop(tp1) != get_type_tpop(tp2)) {
366 /* different type structure */
369 if (is_Class_type(tp1)) {
370 /* check class hierarchy */
371 if (! is_SubClass_of(tp1, tp2) &&
372 ! is_SubClass_of(tp2, tp1))
375 /* different types */
381 } /* different_types */
384 * Check if an offset is a constant and these constant is bigger or equal
387 static int check_const_offset(ir_node *offset, int size) {
388 ir_mode *mode = get_irn_mode(offset);
390 /* ok, we found an offset, check for constant */
391 if (is_Const(offset) && mode_is_int(mode)) {
392 tarval *tv = new_tarval_from_long(size, mode);
394 /* size <= offset ? */
395 if (tarval_cmp(tv, get_Const_tarval(offset)) & (pn_Cmp_Eq|pn_Cmp_Lt))
399 } /* check_const_offset */
402 * Check if we can determine that the two pointers always have an offset bigger
405 static ir_alias_relation _different_pointer(ir_node *adr1, ir_node *adr2, int size) {
409 /* first address is the result of a pointer addition */
410 ir_node *l1 = get_Add_left(adr1);
411 ir_node *r1 = get_Add_right(adr1);
414 found = check_const_offset(r1, size);
415 } else if (r1 == adr2) {
416 found = check_const_offset(l1, size);
417 } else if (is_Add(adr2)) {
418 /* second address is the result of a pointer addition */
419 ir_node *l2 = get_Add_left(adr2);
420 ir_node *r2 = get_Add_right(adr2);
423 return _different_pointer(r1, r2, size);
424 } else if (l1 == r2) {
425 return _different_pointer(r1, l2, size);
426 } else if (r1 == l2) {
427 return _different_pointer(l1, r2, size);
428 } else if (r1 == r2) {
429 return _different_pointer(l1, l2, size);
432 } else if (is_Add(adr2)) {
433 /* second address is the result of a pointer addition */
434 ir_node *l2 = get_Add_left(adr2);
435 ir_node *r2 = get_Add_right(adr2);
438 found = check_const_offset(r2, size);
439 } else if (r2 == adr1) {
440 found = check_const_offset(l2, size);
443 return different_index(adr1, adr2, size);
445 return found ? no_alias : may_alias;
446 } /* _different_pointer */
449 * Check if we can determine that the two pointers always have an offset bigger
450 * then the maximum size of mode1, mode2
452 static ir_alias_relation different_pointer(ir_node *adr1, ir_mode *mode1, ir_node *adr2, ir_mode *mode2) {
453 int size = get_mode_size_bytes(mode1);
454 int n = get_mode_size_bytes(mode2);
458 return _different_pointer(adr1, adr2, size);
459 } /* different_pointer */
462 * Returns non-zero if a node is a routine parameter.
464 * @param node the Proj node to test
466 static int is_arg_Proj(ir_node *node) {
467 node = get_Proj_pred(node);
470 return pn_Start_T_args == get_Proj_proj(node) && is_Start(get_Proj_pred(node));
474 * Returns non-zero if a node is a result on a malloc-like routine.
476 * @param node the Proj node to test
478 static int is_malloc_Result(ir_node *node) {
479 node = get_Proj_pred(node);
482 node = get_Proj_pred(node);
485 node = get_Call_ptr(node);
486 if (is_SymConst_addr_ent(node)) {
487 ir_entity *ent = get_SymConst_entity(node);
489 if (get_entity_additional_properties(ent) & mtp_property_malloc)
494 } /* is_malloc_Result */
497 * Returns true if an address represents a global variable.
499 * @param irn the node representing the address
501 static INLINE int is_global_var(ir_node *irn) {
502 return is_SymConst_addr_ent(irn);
503 } /* is_global_var */
506 * Determine the alias relation between two addresses.
508 static ir_alias_relation _get_alias_relation(
510 ir_node *adr1, ir_mode *mode1,
511 ir_node *adr2, ir_mode *mode2)
514 ir_entity *ent1, *ent2;
516 ir_alias_relation rel;
518 if (! get_opt_alias_analysis())
524 options = get_irg_memory_disambiguator_options(irg);
526 /* The Armageddon switch */
527 if (options & aa_opt_no_alias)
530 /* Two save some code, sort the addresses by its id's. Beware, this
531 might break some things, so better check here. */
532 assert(iro_SymConst < iro_Sel && iro_Sel < iro_Proj && "Code dependence broken");
533 op1 = get_irn_opcode(adr1);
534 op2 = get_irn_opcode(adr2);
545 /* some pointers, check if they have the same base but different offset */
546 rel = different_pointer(adr1, mode1, adr2, mode2);
547 if (rel != may_alias)
550 if (is_global_var(adr1)) {
551 /* first address is a global variable */
553 if (is_global_var(adr2)) {
554 /* both addresses are global variables and we know
555 they are different (R1 a) */
556 if (get_SymConst_entity(adr1) != get_SymConst_entity(adr2))
559 /* equal entity addresses */
562 } else if (is_Sel(adr2)) {
563 ir_node *base2 = find_base_adr(adr2, &ent2);
565 if (is_global_var(base2)) {
566 /* base2 address is a global var (R1 a) */
569 } else if (base2 == get_irg_frame(irg)) {
570 /* the second one is a local variable so they are always
573 } else if (base2 == get_irg_tls(irg)) {
574 /* the second one is a TLS variable so they are always
577 } else if (is_Proj(base2)) {
578 if (is_malloc_Result(base2)) {
579 /* the second one is an offset from a result of a malloc like call, ie.
580 freshly allocated non-aliases heap memory, (R1 f) */
584 } else if (is_Proj(adr2)) {
585 if (is_malloc_Result(adr2)) {
586 /* the second one is a result of a malloc like call, ie.
587 freshly allocated non-aliases heap memory, (R1 f) */
592 /* Here we are: the first is a global var, the second some pointer. */
593 ent1 = get_SymConst_entity(adr1);
594 if (get_entity_address_taken(ent1) == ir_address_not_taken) {
595 /* The address of the global variable was never taken, so
596 the pointer cannot match (R2). */
599 } else if (is_Sel(adr1)) {
600 /* the first address is a Sel */
601 ir_node *base1 = find_base_adr(adr1, &ent1);
603 if (base1 == get_irg_frame(irg)) {
604 /* first is a local variable ent1 */
606 /* the second address is a Sel */
607 ir_node *base2 = find_base_adr(adr2, &ent2);
609 if (base1 == base2) {
610 /* identical bases: both are local variables */
612 /* both addresses are local variables and we know
613 they are different (R1 a) */
617 return different_sel_offsets(adr1, adr2);
619 } else if (base2 == get_irg_tls(irg)) {
620 /* the second one is a TLS variable so they are always
623 } else if (is_Proj(base2)) {
624 if (is_arg_Proj(base2)) {
625 /* the second one is an offset from a parameter so they are
626 always different (R1 e) */
628 } else if (is_malloc_Result(base2)) {
629 /* the second one is an offset from a result of a malloc like call, ie.
630 freshly allocated non-aliases heap memory (R1 g) */
634 } else if (is_Proj(adr2)) {
635 if (is_arg_Proj(adr2)) {
636 /* a local variable and a parameter are always different (R1 e) */
638 } else if (is_malloc_Result(adr2)) {
639 /* the second one is a result of a malloc like call, ie.
640 freshly allocated non-aliases heap memory (R1 g) */
644 } else if (base1 == get_irg_tls(irg)) {
645 /* the first is a TLS variable */
647 /* the second address is a Sel */
648 ir_node *base2 = find_base_adr(adr2, &ent2);
650 if (base1 == base2) {
652 /* both addresses are tls variables and we know
653 they are different (R1 a) */
657 return different_sel_offsets(adr1, adr2);
659 } else if (base2 == get_irg_frame(irg)) {
660 /* the first one is a tls variable, the second a local one,
661 they are different (R1 d) */
663 } else if (is_Proj(base2)) {
664 if (is_malloc_Result(base2)) {
665 /* the second one is an offset from a result of a malloc like call, ie.
666 freshly allocated non-aliases heap memory (R1 h) */
670 } else if (is_Proj(adr2)) {
671 if (is_malloc_Result(adr2)) {
672 /* the second one is an offset from a result of a malloc like call, ie.
673 freshly allocated non-aliases heap memory (R1 h) */
677 } else if (is_Proj(base1)) {
678 if (is_arg_Proj(base1)) {
679 /* the first one is an offset from a parameter */
681 /* the second address is a Sel */
682 ir_node *base2 = find_base_adr(adr2, &ent2);
684 if (base2 == get_irg_frame(irg)) {
685 /* the second one is a local variable so they are always
688 } else if (is_Proj(base2)) {
689 if (is_malloc_Result(base2)) {
690 /* the second one is an offset from a result of a malloc like call, ie.
691 freshly allocated non-aliases heap memory (R1 Ã) */
695 } else if (is_Proj(adr2)) {
696 if (is_malloc_Result(adr2)) {
697 /* the second one is a malloc like call, ie.
698 freshly allocated non-aliases heap memory (R1 Ã) */
703 } else if (is_global_var(base1)) {
704 /* the first one is an offset from a global variable */
705 ent1 = get_SymConst_entity(base1);
707 /* the second address is a Sel */
708 ir_node *base2 = find_base_adr(adr2, &ent2);
710 if (base1 == base2) {
711 /* same global var */
712 return different_sel_offsets(adr1, adr2);
713 } else if (base2 == get_irg_frame(irg)) {
714 /* the second one is a local variable so they are always
717 } else if (base2 == get_irg_tls(irg)) {
718 /* the second one is a TLS variable so they are always
721 } else if (is_Proj(base2)) {
722 if (is_arg_Proj(base2)) {
723 if (get_entity_address_taken(ent1) == ir_address_not_taken) {
724 /* The address of the global variable was never taken, so
725 the pointer cannot match (R2). */
728 } else if (is_malloc_Result(base2)) {
729 /* the second one is an offset from a result of a malloc like call, ie.
730 freshly allocated non-aliases heap memory (R1 g) */
733 } else if (is_global_var(base2)) {
734 ent2 = get_SymConst_entity(base2);
735 /* both addresses are global variables and we know
736 they are different (R1 a) */
743 /* Note: we cannot check for malloc result here, as we cannot be sure
744 * the result is not stored anywhere after getting if.
748 if (options & aa_opt_type_based) { /* Type based alias analysis */
749 ir_alias_relation rel;
751 if (options & aa_opt_byte_type_may_alias) {
752 if (get_mode_size_bits(mode1) == 8 || get_mode_size_bits(mode2) == 8) {
753 /* One of the modes address a byte. Assume a may_alias and leave
754 the type based check. */
755 goto leave_type_based_alias;
758 /* cheap check: If the mode sizes did not match, the types MUST be different */
759 if (get_mode_size_bits(mode1) != get_mode_size_bits(mode2))
762 /* cheap test: if only one is a reference mode, no alias */
763 if (mode_is_reference(mode1) != mode_is_reference(mode2))
767 rel = different_types(adr1, adr2);
768 if (rel != may_alias)
770 leave_type_based_alias:;
773 /* do we have a language specific memory disambiguator? */
774 if (language_disambuigator) {
775 ir_alias_relation rel = (*language_disambuigator)(irg, adr1, mode1, adr2, mode2);
776 if (rel != may_alias)
780 /* access points-to information here */
782 } /* _get_alias_relation */
785 * Determine the alias relation between two addresses.
787 ir_alias_relation get_alias_relation(
789 ir_node *adr1, ir_mode *mode1,
790 ir_node *adr2, ir_mode *mode2)
792 ir_alias_relation rel = _get_alias_relation(irg, adr1, mode1, adr2, mode2);
793 DB((dbg, LEVEL_1, "alias(%+F, %+F) = %s\n", adr1, adr2, get_ir_alias_relation_name(rel)));
795 } /* get_alias_relation */
797 /* Set a source language specific memory disambiguator function. */
798 void set_language_memory_disambiguator(DISAMBIGUATOR_FUNC func) {
799 language_disambuigator = func;
800 } /* set_language_memory_disambiguator */
802 /** The result cache for the memory disambiguator. */
803 static set *result_cache = NULL;
805 /** An entry in the relation cache. */
806 typedef struct mem_disambig_entry {
807 ir_node *adr1; /**< The first address. */
808 ir_node *adr2; /**< The second address. */
809 ir_alias_relation result; /**< The alias relation result. */
810 } mem_disambig_entry;
812 #define HASH_ENTRY(adr1, adr2) (HASH_PTR(adr1) ^ HASH_PTR(adr2))
815 * Compare two relation cache entries.
817 static int cmp_mem_disambig_entry(const void *elt, const void *key, size_t size) {
818 const mem_disambig_entry *p1 = elt;
819 const mem_disambig_entry *p2 = key;
822 return p1->adr1 == p2->adr1 && p1->adr2 == p2->adr2;
823 } /* cmp_mem_disambig_entry */
826 * Initialize the relation cache.
828 void mem_disambig_init(void) {
829 result_cache = new_set(cmp_mem_disambig_entry, 8);
830 } /* mem_disambig_init */
833 * Determine the alias relation between two addresses.
835 ir_alias_relation get_alias_relation_ex(
837 ir_node *adr1, ir_mode *mode1,
838 ir_node *adr2, ir_mode *mode2)
840 mem_disambig_entry key, *entry;
842 ir_fprintf(stderr, "%+F <-> %+F\n", adr1, adr2);
844 if (! get_opt_alias_analysis())
847 if (get_irn_opcode(adr1) > get_irn_opcode(adr2)) {
855 entry = set_find(result_cache, &key, sizeof(key), HASH_ENTRY(adr1, adr2));
857 return entry->result;
859 key.result = get_alias_relation(irg, adr1, mode1, adr2, mode2);
861 set_insert(result_cache, &key, sizeof(key), HASH_ENTRY(adr1, adr2));
863 } /* get_alias_relation_ex */
865 /* Free the relation cache. */
866 void mem_disambig_term(void) {
868 del_set(result_cache);
871 } /* mem_disambig_term */
874 * Check the mode of a Load/Store with the mode of the entity
876 * If the mode of the entity and the Load/Store mode do not match, we
877 * have the bad reinterpret case:
880 * char b = *(char *)&i;
882 * We do NOT count this as one value and return address_taken
884 * However, we support an often used case. If the mode is two-complement
885 * we allow casts between signed/unsigned.
887 * @param mode the mode of the Load/Store
888 * @param ent_mode the mode of the accessed entity
890 * @return non-zero if the Load/Store is a hidden cast, zero else
892 static int is_hidden_cast(ir_mode *mode, ir_mode *ent_mode) {
893 if (ent_mode != mode) {
894 if (ent_mode == NULL ||
895 get_mode_size_bits(ent_mode) != get_mode_size_bits(mode) ||
896 get_mode_sort(ent_mode) != get_mode_sort(mode) ||
897 get_mode_arithmetic(ent_mode) != irma_twos_complement ||
898 get_mode_arithmetic(mode) != irma_twos_complement)
902 } /* is_hidden_cast */
905 * Determine the address_taken state of a node (or it's successor Sels).
907 * @param irn the node
909 static ir_address_taken_state find_address_taken_state(ir_node *irn) {
911 ir_mode *emode, *mode;
915 for (i = get_irn_n_outs(irn) - 1; i >= 0; --i) {
916 ir_node *succ = get_irn_out(irn, i);
918 switch (get_irn_opcode(succ)) {
920 /* check if this load is not a hidden conversion */
921 mode = get_Load_mode(succ);
922 ent = is_SymConst(irn) ? get_SymConst_entity(irn) : get_Sel_entity(irn);
923 emode = get_type_mode(get_entity_type(ent));
924 if (is_hidden_cast(mode, emode))
925 return ir_address_taken;
929 /* check that the node is not the Store's value */
930 value = get_Store_value(succ);
932 return ir_address_taken;
933 /* check if this Store is not a hidden conversion */
934 mode = get_irn_mode(value);
935 ent = is_SymConst(irn) ? get_SymConst_entity(irn) : get_Sel_entity(irn);
936 emode = get_type_mode(get_entity_type(ent));
937 if (is_hidden_cast(mode, emode))
938 return ir_address_taken;
942 /* Check the successor of irn. */
943 ir_address_taken_state res = find_address_taken_state(succ);
944 if (res != ir_address_not_taken)
950 /* Only the call address is not an address taker but
951 this is an uninteresting case, so we ignore it here. */
952 for (j = get_Call_n_params(succ) - 1; j >= 0; --j) {
953 ir_node *param = get_Call_param(succ, j);
955 return ir_address_taken;
960 /* another op, the address may be taken */
961 return ir_address_taken_unknown;
964 /* All successors finished, the address is not taken. */
965 return ir_address_not_taken;
966 } /* find_address_taken_state */
969 * Update the "address taken" flag of all frame entities.
971 static void analyse_irg_address_taken(ir_graph *irg) {
972 ir_type *ft = get_irg_frame_type(irg);
976 /* set initial state to not_taken, as this is the "smallest" state */
977 for (i = get_class_n_members(ft) - 1; i >= 0; --i) {
978 ir_entity *ent = get_class_member(ft, i);
980 set_entity_address_taken(ent, ir_address_not_taken);
983 assure_irg_outs(irg);
985 irg_frame = get_irg_frame(irg);
987 for (i = get_irn_n_outs(irg_frame) - 1; i >= 0; --i) {
988 ir_node *succ = get_irn_out(irg_frame, i);
989 ir_address_taken_state state;
992 ir_entity *ent = get_Sel_entity(succ);
994 if (get_entity_address_taken(ent) == ir_address_taken)
997 state = find_address_taken_state(succ);
998 if (state > get_entity_address_taken(ent))
999 set_entity_address_taken(ent, state);
1003 irg->adr_taken_state = ir_address_taken_computed;
1004 } /* analyse_address_taken */
1006 /* Returns the current address taken state of the graph. */
1007 ir_address_taken_computed_state get_irg_address_taken_state(const ir_graph *irg) {
1008 return irg->adr_taken_state;
1009 } /* get_irg_address_taken_state */
1011 /* Sets the current address taken state of the graph. */
1012 void set_irg_address_taken_state(ir_graph *irg, ir_address_taken_computed_state state) {
1013 irg->adr_taken_state = state;
1014 } /* set_irg_address_taken_state */
1016 /* Assure that the address taken flag is computed for the given graph. */
1017 void assure_irg_address_taken_computed(ir_graph *irg) {
1018 if (irg->adr_taken_state == ir_address_taken_not_computed)
1019 analyse_irg_address_taken(irg);
1020 } /* assure_irg_address_taken_computed */
1024 * Initialize the address_taken flag for a global type like type.
1026 static void init_taken_flag(ir_type * tp) {
1029 /* All external visible entities are at least
1030 ir_address_taken_unknown. This is very conservative. */
1031 for (i = get_compound_n_members(tp) - 1; i >= 0; --i) {
1032 ir_entity *ent = get_compound_member(tp, i);
1033 ir_address_taken_state state;
1035 state = get_entity_visibility(ent) == visibility_external_visible ?
1036 ir_address_taken_unknown : ir_address_not_taken ;
1037 set_entity_address_taken(ent, state);
1039 } /* init_taken_flag */
1041 static void check_initializer_nodes(ir_initializer_t *initializer)
1043 switch(initializer->kind) {
1044 case IR_INITIALIZER_CONST: {
1045 ir_node *n = initializer->consti.value;
1047 /* let's check if it's an address */
1048 if (is_SymConst_addr_ent(n)) {
1049 ir_entity *ent = get_SymConst_entity(n);
1050 set_entity_address_taken(ent, ir_address_taken);
1054 case IR_INITIALIZER_TARVAL:
1055 case IR_INITIALIZER_NULL:
1057 case IR_INITIALIZER_COMPOUND: {
1060 for(i = 0; i < initializer->compound.n_initializers; ++i) {
1061 ir_initializer_t *sub_initializer
1062 = initializer->compound.initializers[i];
1063 check_initializer_nodes(sub_initializer);
1068 panic("invalid initialzier found");
1072 * Mark all entities used in the initializer for the given entity as address taken
1074 static void check_initializer(ir_entity *ent) {
1078 /* do not check uninitialized values */
1079 if (get_entity_variability(ent) == variability_uninitialized)
1082 /* Beware: Methods initialized with "themself". This does not count as a taken
1084 if (is_Method_type(get_entity_type(ent)))
1087 if (ent->has_initializer) {
1088 check_initializer_nodes(ent->attr.initializer);
1089 } else if (is_atomic_entity(ent)) {
1090 /* let's check if it's an address */
1091 n = get_atomic_ent_value(ent);
1092 if (is_SymConst_addr_ent(n)) {
1093 ir_entity *ent = get_SymConst_entity(n);
1094 set_entity_address_taken(ent, ir_address_taken);
1097 for (i = get_compound_ent_n_values(ent) - 1; i >= 0; --i) {
1098 n = get_compound_ent_value(ent, i);
1100 /* let's check if it's an address */
1101 if (is_SymConst_addr_ent(n)) {
1102 ir_entity *ent = get_SymConst_entity(n);
1103 set_entity_address_taken(ent, ir_address_taken);
1107 } /* check_initializer */
1111 * Mark all entities used in initializers as address taken
1113 static void check_initializers(ir_type *tp) {
1116 for (i = get_compound_n_members(tp) - 1; i >= 0; --i) {
1117 ir_entity *ent = get_compound_member(tp, i);
1119 check_initializer(ent);
1121 } /* check_initializers */
1123 #ifdef DEBUG_libfirm
1125 * Print the address taken state of all entities of a given type for debugging.
1127 static void print_address_taken_state(ir_type *tp) {
1129 for (i = get_compound_n_members(tp) - 1; i >= 0; --i) {
1130 ir_entity *ent = get_compound_member(tp, i);
1131 ir_address_taken_state state = get_entity_address_taken(ent);
1133 if (state != ir_address_not_taken) {
1134 assert(ir_address_not_taken <= (int) state && state <= ir_address_taken);
1135 ir_printf("%+F: %s\n", ent, get_address_taken_state_name(state));
1138 } /* print_address_taken_state */
1139 #endif /* DEBUG_libfirm */
1142 * Post-walker: check for global entity address
1144 static void check_global_address(ir_node *irn, void *env) {
1147 ir_address_taken_state state;
1149 if (is_SymConst_addr_ent(irn)) {
1151 ent = get_SymConst_entity(irn);
1152 } else if (is_Sel(irn) && get_Sel_ptr(irn) == tls) {
1153 /* A TLS variable. */
1154 ent = get_Sel_entity(irn);
1158 if (get_entity_address_taken(ent) >= ir_address_taken) {
1159 /* Already at the maximum. */
1162 state = find_address_taken_state(irn);
1163 if (state > get_entity_address_taken(ent))
1164 set_entity_address_taken(ent, state);
1165 } /* check_global_address */
1168 * Update the "address taken" flag of all global entities.
1170 static void analyse_irp_globals_address_taken(void) {
1173 FIRM_DBG_REGISTER(dbg, "firm.ana.irmemory");
1175 init_taken_flag(get_glob_type());
1176 init_taken_flag(get_tls_type());
1178 check_initializers(get_glob_type());
1179 check_initializers(get_tls_type());
1181 for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
1182 ir_graph *irg = get_irp_irg(i);
1184 assure_irg_outs(irg);
1185 irg_walk_graph(irg, NULL, check_global_address, get_irg_tls(irg));
1188 #ifdef DEBUG_libfirm
1189 if (firm_dbg_get_mask(dbg) & LEVEL_1) {
1190 print_address_taken_state(get_glob_type());
1191 print_address_taken_state(get_tls_type());
1193 #endif /* DEBUG_libfirm */
1196 irp->globals_adr_taken_state = ir_address_taken_computed;
1197 } /* analyse_irp_globals_address_taken */
1199 /* Returns the current address taken state of the globals. */
1200 ir_address_taken_computed_state get_irp_globals_address_taken_state(void) {
1201 return irp->globals_adr_taken_state;
1202 } /* get_irp_globals_address_taken_state */
1204 /* Sets the current address taken state of the graph. */
1205 void set_irp_globals_address_taken_state(ir_address_taken_computed_state state) {
1206 irp->globals_adr_taken_state = state;
1207 } /* set_irg_address_taken_state */
1209 /* Assure that the address taken flag is computed for the globals. */
1210 void assure_irp_globals_address_taken_computed(void) {
1211 if (irp->globals_adr_taken_state == ir_address_taken_not_computed)
1212 analyse_irp_globals_address_taken();
1213 } /* assure_irp_globals_address_taken_computed */
1216 #include <adt/pmap.h>
1217 #include "typerep.h"
1219 DEBUG_ONLY(static firm_dbg_module_t *dbgcall = NULL;)
1221 /** Maps method types to cloned method types. */
1222 static pmap *mtp_map;
1225 * Clone a method type if not already cloned.
1227 static ir_type *clone_type_and_cache(ir_type *tp) {
1228 static ident *prefix = NULL;
1230 pmap_entry *e = pmap_find(mtp_map, tp);
1236 prefix = new_id_from_chars("C", 1);
1238 res = clone_type_method(tp, prefix);
1239 pmap_insert(mtp_map, tp, res);
1240 DB((dbgcall, LEVEL_2, "cloned type %+F into %+F\n", tp, res));
1243 } /* clone_type_and_cache */
1246 * Copy the calling conventions from the entities to the call type.
1248 static void update_calls_to_private(ir_node *call, void *env) {
1250 if (is_Call(call)) {
1251 ir_node *ptr = get_Call_ptr(call);
1253 if (is_SymConst(ptr)) {
1254 ir_entity *ent = get_SymConst_entity(ptr);
1255 ir_type *ctp = get_Call_type(call);
1257 if (get_entity_additional_properties(ent) & mtp_property_private) {
1258 if ((get_method_additional_properties(ctp) & mtp_property_private) == 0) {
1259 ctp = clone_type_and_cache(ctp);
1260 set_method_additional_property(ctp, mtp_property_private);
1261 set_Call_type(call, ctp);
1262 DB((dbgcall, LEVEL_1, "changed call to private method %+F\n", ent));
1267 } /* update_calls_to_private */
1269 /* Mark all private methods, i.e. those of which all call sites are known. */
1270 void mark_private_methods(void) {
1274 FIRM_DBG_REGISTER(dbgcall, "firm.opt.cc");
1276 assure_irp_globals_address_taken_computed();
1278 mtp_map = pmap_create();
1280 /* first step: change the calling conventions of the local non-escaped entities */
1281 for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
1282 ir_graph *irg = get_irp_irg(i);
1283 ir_entity *ent = get_irg_entity(irg);
1284 ir_address_taken_state state = get_entity_address_taken(ent);
1286 if (get_entity_visibility(ent) == visibility_local &&
1287 state == ir_address_not_taken) {
1288 ir_type *mtp = get_entity_type(ent);
1290 set_entity_additional_property(ent, mtp_property_private);
1291 DB((dbgcall, LEVEL_1, "found private method %+F\n", ent));
1292 if ((get_method_additional_properties(mtp) & mtp_property_private) == 0) {
1293 /* need a new type */
1294 mtp = clone_type_and_cache(mtp);
1295 set_entity_type(ent, mtp);
1296 set_method_additional_property(mtp, mtp_property_private);
1303 all_irg_walk(NULL, update_calls_to_private, NULL);
1305 pmap_destroy(mtp_map);
1306 } /* mark_private_methods */