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;
343 ent1 = get_Global_entity(adr1);
344 else if (is_Sel(adr1))
345 ent1 = get_Sel_entity(adr1);
348 ent2 = get_Global_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 * Returns non-zero if a node is a routine parameter.
386 * @param node the Proj node to test
388 static int is_arg_Proj(ir_node *node) {
391 node = get_Proj_pred(node);
394 return pn_Start_T_args == get_Proj_proj(node) && is_Start(get_Proj_pred(node));
398 * Returns non-zero if a node is a result on a malloc-like routine.
400 * @param node the Proj node to test
402 static int is_malloc_Result(ir_node *node) {
403 node = get_Proj_pred(node);
406 node = get_Proj_pred(node);
409 node = get_Call_ptr(node);
410 if (is_Global(node)) {
411 ir_entity *ent = get_Global_entity(node);
413 if (get_entity_additional_properties(ent) & mtp_property_malloc)
418 } /* is_malloc_Result */
421 * classify storage locations.
422 * Except STORAGE_CLASS_POINTER they are all disjoint.
423 * STORAGE_CLASS_POINTER potentially aliases all classes which don't have a
427 STORAGE_CLASS_POINTER = 0x0000,
428 STORAGE_CLASS_GLOBALVAR = 0x0001,
429 STORAGE_CLASS_LOCALVAR = 0x0002,
430 STORAGE_CLASS_ARGUMENT = 0x0003,
431 STORAGE_CLASS_TLS = 0x0004,
432 STORAGE_CLASS_MALLOCED = 0x0005,
434 STORAGE_CLASS_MODIFIER_NOTTAKEN = 0x1000,
435 } storage_class_class_t;
438 * Classify a base pointer.
440 * @param irg the graph of the pointer
441 * @param irn the node representing the base address
442 * @param ent the base entity of the base address iff any
444 static storage_class_class_t classify_pointer(ir_graph *irg, ir_node *irn, ir_entity *ent)
446 storage_class_class_t res = STORAGE_CLASS_POINTER;
447 if (is_Global(irn)) {
448 ir_entity *entity = get_Global_entity(irn);
449 res = STORAGE_CLASS_GLOBALVAR;
450 if (get_entity_address_taken(entity) == ir_address_not_taken)
451 res |= STORAGE_CLASS_MODIFIER_NOTTAKEN;
452 } else if (irn == get_irg_frame(irg)) {
453 res = STORAGE_CLASS_LOCALVAR;
454 if (ent != NULL && get_entity_address_taken(ent) == ir_address_not_taken)
455 res |= STORAGE_CLASS_MODIFIER_NOTTAKEN;
456 } else if (is_arg_Proj(irn)) {
457 return STORAGE_CLASS_ARGUMENT;
458 } else if (irn == get_irg_tls(irg)) {
459 res = STORAGE_CLASS_TLS;
460 if (ent != NULL && get_entity_address_taken(ent) == ir_address_not_taken)
461 res |= STORAGE_CLASS_MODIFIER_NOTTAKEN;
462 } else if (is_Proj(irn) && is_malloc_Result(irn)) {
463 return STORAGE_CLASS_MALLOCED;
470 * If adr represents a Bitfield Sel, skip it
472 static ir_node *skip_Bitfield_Sels(ir_node *adr) {
474 ir_entity *ent = get_Sel_entity(adr);
475 ir_type *bf_type = get_entity_type(ent);
477 /* is it a bitfield type? */
478 if (is_Primitive_type(bf_type) && get_primitive_base_type(bf_type) != NULL)
479 adr = get_Sel_ptr(adr);
485 * Determine the alias relation between two addresses.
487 static ir_alias_relation _get_alias_relation(
489 ir_node *adr1, ir_mode *mode1,
490 ir_node *adr2, ir_mode *mode2)
492 ir_entity *ent1, *ent2;
498 ir_node *orig_adr1 = adr1;
499 ir_node *orig_adr2 = adr2;
501 storage_class_class_t class1, class2;
502 int have_const_offsets;
504 if (! get_opt_alias_analysis())
510 options = get_irg_memory_disambiguator_options(irg);
512 /* The Armageddon switch */
513 if (options & aa_opt_no_alias)
516 /* do the addresses have constants offsets?
517 * Note: nodes are normalized to have constants at right inputs,
518 * sub X, C is normalized to add X, -C
520 have_const_offsets = 1;
521 while (is_Add(adr1)) {
522 ir_node *add_right = get_Add_right(adr1);
523 if (is_Const(add_right)) {
524 tarval *tv = get_Const_tarval(add_right);
525 offset1 += get_tarval_long(tv);
526 adr1 = get_Add_left(adr1);
527 } else if (mode_is_reference(get_irn_mode(add_right))) {
529 have_const_offsets = 0;
531 adr1 = get_Add_left(adr1);
532 have_const_offsets = 0;
535 while (is_Add(adr2)) {
536 ir_node *add_right = get_Add_right(adr2);
537 if (is_Const(add_right)) {
538 tarval *tv = get_Const_tarval(add_right);
539 offset2 += get_tarval_long(tv);
540 adr2 = get_Add_left(adr2);
541 } else if (mode_is_reference(get_irn_mode(add_right))) {
543 have_const_offsets = 0;
545 adr2 = get_Add_left(adr2);
546 have_const_offsets = 0;
550 mode_size = get_mode_size_bytes(mode1);
551 if (get_mode_size_bytes(mode2) > mode_size) {
552 mode_size = get_mode_size_bytes(mode2);
555 /* same base address -> compare offsets if possible.
556 * FIXME: type long is not sufficient for this task ...
558 if (adr1 == adr2 && have_const_offsets) {
559 if ((unsigned long)labs(offset2 - offset1) >= mode_size)
566 * Bitfields can be constructed as Sels from its base address.
567 * As they have different entities, the disambiguator would find that they are
568 * alias free. While this is true vor it's values, it is false for the addresses
569 * (strictly speaking, the Sel's are NOT the addresses of the bitfields).
570 * So, skip those bitfield selecting Sel's.
572 adr1 = skip_Bitfield_Sels(adr1);
573 adr2 = skip_Bitfield_Sels(adr2);
581 base1 = find_base_adr(adr1, &ent1);
584 base2 = find_base_adr(adr2, &ent2);
587 /* same base address -> compare sel entities */
588 if (base1 == base2 && ent1 != NULL && ent2 != NULL) {
591 else if (have_const_offsets)
592 return different_sel_offsets(adr1, adr2);
595 class1 = classify_pointer(irg, base1, ent1);
596 class2 = classify_pointer(irg, base2, ent2);
598 if (class1 == STORAGE_CLASS_POINTER) {
599 if (class2 & STORAGE_CLASS_MODIFIER_NOTTAKEN) {
604 } else if (class2 == STORAGE_CLASS_POINTER) {
605 if (class1 & STORAGE_CLASS_MODIFIER_NOTTAKEN) {
612 if (class1 != class2) {
616 if (class1 == STORAGE_CLASS_GLOBALVAR) {
617 ir_entity *entity1 = get_SymConst_entity(base1);
618 ir_entity *entity2 = get_SymConst_entity(base2);
619 if (entity1 != entity2)
622 /* for some reason CSE didn't happen yet for the 2 SymConsts... */
626 /* Type based alias analysis */
627 if (options & aa_opt_type_based) {
628 ir_alias_relation rel;
630 if (options & aa_opt_byte_type_may_alias) {
631 if (get_mode_size_bits(mode1) == 8 || get_mode_size_bits(mode2) == 8) {
632 /* One of the modes address a byte. Assume a may_alias and leave
633 the type based check. */
634 goto leave_type_based_alias;
637 /* cheap check: If the mode sizes did not match, the types MUST be different */
638 if (get_mode_size_bits(mode1) != get_mode_size_bits(mode2))
641 /* cheap test: if only one is a reference mode, no alias */
642 if (mode_is_reference(mode1) != mode_is_reference(mode2))
646 rel = different_types(orig_adr1, orig_adr2);
647 if (rel != may_alias)
649 leave_type_based_alias:;
652 /* do we have a language specific memory disambiguator? */
653 if (language_disambuigator) {
654 ir_alias_relation rel = (*language_disambuigator)(irg, orig_adr1, mode1, orig_adr2, mode2);
655 if (rel != may_alias)
659 /* access points-to information here */
661 } /* _get_alias_relation */
664 * Determine the alias relation between two addresses.
666 ir_alias_relation get_alias_relation(
668 ir_node *adr1, ir_mode *mode1,
669 ir_node *adr2, ir_mode *mode2)
671 ir_alias_relation rel = _get_alias_relation(irg, adr1, mode1, adr2, mode2);
672 DB((dbg, LEVEL_1, "alias(%+F, %+F) = %s\n", adr1, adr2, get_ir_alias_relation_name(rel)));
674 } /* get_alias_relation */
676 /* Set a source language specific memory disambiguator function. */
677 void set_language_memory_disambiguator(DISAMBIGUATOR_FUNC func) {
678 language_disambuigator = func;
679 } /* set_language_memory_disambiguator */
681 /** The result cache for the memory disambiguator. */
682 static set *result_cache = NULL;
684 /** An entry in the relation cache. */
685 typedef struct mem_disambig_entry {
686 ir_node *adr1; /**< The first address. */
687 ir_node *adr2; /**< The second address. */
688 ir_alias_relation result; /**< The alias relation result. */
689 } mem_disambig_entry;
691 #define HASH_ENTRY(adr1, adr2) (HASH_PTR(adr1) ^ HASH_PTR(adr2))
694 * Compare two relation cache entries.
696 static int cmp_mem_disambig_entry(const void *elt, const void *key, size_t size) {
697 const mem_disambig_entry *p1 = elt;
698 const mem_disambig_entry *p2 = key;
701 return p1->adr1 == p2->adr1 && p1->adr2 == p2->adr2;
702 } /* cmp_mem_disambig_entry */
705 * Initialize the relation cache.
707 void mem_disambig_init(void) {
708 result_cache = new_set(cmp_mem_disambig_entry, 8);
709 } /* mem_disambig_init */
712 * Determine the alias relation between two addresses.
714 ir_alias_relation get_alias_relation_ex(
716 ir_node *adr1, ir_mode *mode1,
717 ir_node *adr2, ir_mode *mode2)
719 mem_disambig_entry key, *entry;
721 ir_fprintf(stderr, "%+F <-> %+F\n", adr1, adr2);
723 if (! get_opt_alias_analysis())
726 if (get_irn_opcode(adr1) > get_irn_opcode(adr2)) {
734 entry = set_find(result_cache, &key, sizeof(key), HASH_ENTRY(adr1, adr2));
736 return entry->result;
738 key.result = get_alias_relation(irg, adr1, mode1, adr2, mode2);
740 set_insert(result_cache, &key, sizeof(key), HASH_ENTRY(adr1, adr2));
742 } /* get_alias_relation_ex */
744 /* Free the relation cache. */
745 void mem_disambig_term(void) {
747 del_set(result_cache);
750 } /* mem_disambig_term */
753 * Check the mode of a Load/Store with the mode of the entity
755 * If the mode of the entity and the Load/Store mode do not match, we
756 * have the bad reinterpret case:
759 * char b = *(char *)&i;
761 * We do NOT count this as one value and return address_taken
763 * However, we support an often used case. If the mode is two-complement
764 * we allow casts between signed/unsigned.
766 * @param mode the mode of the Load/Store
767 * @param ent_mode the mode of the accessed entity
769 * @return non-zero if the Load/Store is a hidden cast, zero else
771 static int is_hidden_cast(ir_mode *mode, ir_mode *ent_mode) {
772 if (ent_mode != mode) {
773 if (ent_mode == NULL ||
774 get_mode_size_bits(ent_mode) != get_mode_size_bits(mode) ||
775 get_mode_sort(ent_mode) != get_mode_sort(mode) ||
776 get_mode_arithmetic(ent_mode) != irma_twos_complement ||
777 get_mode_arithmetic(mode) != irma_twos_complement)
781 } /* is_hidden_cast */
784 * Determine the address_taken state of a node (or it's successor Sels).
786 * @param irn the node
788 static ir_address_taken_state find_address_taken_state(ir_node *irn) {
790 ir_mode *emode, *mode;
795 for (i = get_irn_n_outs(irn) - 1; i >= 0; --i) {
796 ir_node *succ = get_irn_out(irn, i);
798 switch (get_irn_opcode(succ)) {
800 /* check if this load is not a hidden conversion */
801 mode = get_Load_mode(succ);
802 ent = is_SymConst(irn) ? get_SymConst_entity(irn) : get_Sel_entity(irn);
803 emode = get_type_mode(get_entity_type(ent));
804 if (is_hidden_cast(mode, emode))
805 return ir_address_taken;
809 /* check that the node is not the Store's value */
810 value = get_Store_value(succ);
812 return ir_address_taken;
813 /* check if this Store is not a hidden conversion */
814 mode = get_irn_mode(value);
815 ent = is_SymConst(irn) ? get_SymConst_entity(irn) : get_Sel_entity(irn);
816 emode = get_type_mode(get_entity_type(ent));
817 if (is_hidden_cast(mode, emode))
818 return ir_address_taken;
822 /* CopyB are like Loads/Stores */
823 ent = is_SymConst(irn) ? get_SymConst_entity(irn) : get_Sel_entity(irn);
824 tp = get_entity_type(ent);
825 if (tp != get_CopyB_type(succ)) {
826 /* bad, different types, might be a hidden conversion */
827 return ir_address_taken;
832 /* Check the successor of irn. */
833 ir_address_taken_state res = find_address_taken_state(succ);
834 if (res != ir_address_not_taken)
840 /* Only the call address is not an address taker but
841 this is an uninteresting case, so we ignore it here. */
842 for (j = get_Call_n_params(succ) - 1; j >= 0; --j) {
843 ir_node *param = get_Call_param(succ, j);
845 return ir_address_taken;
850 /* another op, the address may be taken */
851 return ir_address_taken_unknown;
854 /* All successors finished, the address is not taken. */
855 return ir_address_not_taken;
856 } /* find_address_taken_state */
859 * Update the "address taken" flag of all frame entities.
861 static void analyse_irg_address_taken(ir_graph *irg) {
862 ir_type *ft = get_irg_frame_type(irg);
866 /* set initial state to not_taken, as this is the "smallest" state */
867 for (i = get_class_n_members(ft) - 1; i >= 0; --i) {
868 ir_entity *ent = get_class_member(ft, i);
870 set_entity_address_taken(ent, ir_address_not_taken);
873 assure_irg_outs(irg);
875 irg_frame = get_irg_frame(irg);
877 for (i = get_irn_n_outs(irg_frame) - 1; i >= 0; --i) {
878 ir_node *succ = get_irn_out(irg_frame, i);
879 ir_address_taken_state state;
882 ir_entity *ent = get_Sel_entity(succ);
884 if (get_entity_address_taken(ent) == ir_address_taken)
887 state = find_address_taken_state(succ);
888 if (state > get_entity_address_taken(ent))
889 set_entity_address_taken(ent, state);
893 irg->adr_taken_state = ir_address_taken_computed;
894 } /* analyse_address_taken */
896 /* Returns the current address taken state of the graph. */
897 ir_address_taken_computed_state get_irg_address_taken_state(const ir_graph *irg) {
898 return irg->adr_taken_state;
899 } /* get_irg_address_taken_state */
901 /* Sets the current address taken state of the graph. */
902 void set_irg_address_taken_state(ir_graph *irg, ir_address_taken_computed_state state) {
903 irg->adr_taken_state = state;
904 } /* set_irg_address_taken_state */
906 /* Assure that the address taken flag is computed for the given graph. */
907 void assure_irg_address_taken_computed(ir_graph *irg) {
908 if (irg->adr_taken_state == ir_address_taken_not_computed)
909 analyse_irg_address_taken(irg);
910 } /* assure_irg_address_taken_computed */
914 * Initialize the address_taken flag for a global type like type.
916 static void init_taken_flag(ir_type * tp) {
919 /* All external visible entities are at least
920 ir_address_taken_unknown. This is very conservative. */
921 for (i = get_compound_n_members(tp) - 1; i >= 0; --i) {
922 ir_entity *ent = get_compound_member(tp, i);
923 ir_address_taken_state state;
925 state = get_entity_visibility(ent) == visibility_external_visible ?
926 ir_address_taken_unknown : ir_address_not_taken ;
927 set_entity_address_taken(ent, state);
929 } /* init_taken_flag */
931 static void check_initializer_nodes(ir_initializer_t *initializer)
933 switch (initializer->kind) {
934 case IR_INITIALIZER_CONST: {
935 ir_node *n = initializer->consti.value;
937 /* let's check if it's an address */
939 ir_entity *ent = get_Global_entity(n);
940 set_entity_address_taken(ent, ir_address_taken);
944 case IR_INITIALIZER_TARVAL:
945 case IR_INITIALIZER_NULL:
947 case IR_INITIALIZER_COMPOUND: {
950 for (i = 0; i < initializer->compound.n_initializers; ++i) {
951 ir_initializer_t *sub_initializer
952 = initializer->compound.initializers[i];
953 check_initializer_nodes(sub_initializer);
958 panic("invalid initialzier found");
962 * Mark all entities used in the initializer for the given entity as address taken
964 static void check_initializer(ir_entity *ent) {
968 /* do not check uninitialized values */
969 if (get_entity_variability(ent) == variability_uninitialized)
972 /* Beware: Methods initialized with "themself". This does not count as a taken
974 if (is_Method_type(get_entity_type(ent)))
977 if (ent->has_initializer) {
978 check_initializer_nodes(ent->attr.initializer);
979 } else if (is_atomic_entity(ent)) {
980 /* let's check if it's an address */
981 n = get_atomic_ent_value(ent);
983 ir_entity *ent = get_Global_entity(n);
984 set_entity_address_taken(ent, ir_address_taken);
987 for (i = get_compound_ent_n_values(ent) - 1; i >= 0; --i) {
988 n = get_compound_ent_value(ent, i);
990 /* let's check if it's an address */
992 ir_entity *ent = get_Global_entity(n);
993 set_entity_address_taken(ent, ir_address_taken);
997 } /* check_initializer */
1001 * Mark all entities used in initializers as address taken
1003 static void check_initializers(ir_type *tp) {
1006 for (i = get_compound_n_members(tp) - 1; i >= 0; --i) {
1007 ir_entity *ent = get_compound_member(tp, i);
1009 check_initializer(ent);
1011 } /* check_initializers */
1013 #ifdef DEBUG_libfirm
1015 * Print the address taken state of all entities of a given type for debugging.
1017 static void print_address_taken_state(ir_type *tp) {
1019 for (i = get_compound_n_members(tp) - 1; i >= 0; --i) {
1020 ir_entity *ent = get_compound_member(tp, i);
1021 ir_address_taken_state state = get_entity_address_taken(ent);
1023 if (state != ir_address_not_taken) {
1024 assert(ir_address_not_taken <= (int) state && state <= ir_address_taken);
1025 ir_printf("%+F: %s\n", ent, get_address_taken_state_name(state));
1028 } /* print_address_taken_state */
1029 #endif /* DEBUG_libfirm */
1032 * Post-walker: check for global entity address
1034 static void check_global_address(ir_node *irn, void *env) {
1037 ir_address_taken_state state;
1039 if (is_Global(irn)) {
1041 ent = get_Global_entity(irn);
1042 } else if (is_Sel(irn) && get_Sel_ptr(irn) == tls) {
1043 /* A TLS variable. */
1044 ent = get_Sel_entity(irn);
1048 if (get_entity_address_taken(ent) >= ir_address_taken) {
1049 /* Already at the maximum. */
1052 state = find_address_taken_state(irn);
1053 if (state > get_entity_address_taken(ent))
1054 set_entity_address_taken(ent, state);
1055 } /* check_global_address */
1058 * Update the "address taken" flag of all global entities.
1060 static void analyse_irp_globals_address_taken(void) {
1063 FIRM_DBG_REGISTER(dbg, "firm.ana.irmemory");
1065 init_taken_flag(get_glob_type());
1066 init_taken_flag(get_tls_type());
1068 check_initializers(get_glob_type());
1069 check_initializers(get_tls_type());
1071 for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
1072 ir_graph *irg = get_irp_irg(i);
1074 assure_irg_outs(irg);
1075 irg_walk_graph(irg, NULL, check_global_address, get_irg_tls(irg));
1078 #ifdef DEBUG_libfirm
1079 if (firm_dbg_get_mask(dbg) & LEVEL_1) {
1080 print_address_taken_state(get_glob_type());
1081 print_address_taken_state(get_tls_type());
1083 #endif /* DEBUG_libfirm */
1086 irp->globals_adr_taken_state = ir_address_taken_computed;
1087 } /* analyse_irp_globals_address_taken */
1089 /* Returns the current address taken state of the globals. */
1090 ir_address_taken_computed_state get_irp_globals_address_taken_state(void) {
1091 return irp->globals_adr_taken_state;
1092 } /* get_irp_globals_address_taken_state */
1094 /* Sets the current address taken state of the graph. */
1095 void set_irp_globals_address_taken_state(ir_address_taken_computed_state state) {
1096 irp->globals_adr_taken_state = state;
1097 } /* set_irg_address_taken_state */
1099 /* Assure that the address taken flag is computed for the globals. */
1100 void assure_irp_globals_address_taken_computed(void) {
1101 if (irp->globals_adr_taken_state == ir_address_taken_not_computed)
1102 analyse_irp_globals_address_taken();
1103 } /* assure_irp_globals_address_taken_computed */
1106 #include <adt/pmap.h>
1107 #include "typerep.h"
1109 DEBUG_ONLY(static firm_dbg_module_t *dbgcall = NULL;)
1111 /** Maps method types to cloned method types. */
1112 static pmap *mtp_map;
1115 * Clone a method type if not already cloned.
1117 static ir_type *clone_type_and_cache(ir_type *tp) {
1118 static ident *prefix = NULL;
1120 pmap_entry *e = pmap_find(mtp_map, tp);
1126 prefix = new_id_from_chars("C", 1);
1128 res = clone_type_method(tp, prefix);
1129 pmap_insert(mtp_map, tp, res);
1130 DB((dbgcall, LEVEL_2, "cloned type %+F into %+F\n", tp, res));
1133 } /* clone_type_and_cache */
1136 * Copy the calling conventions from the entities to the call type.
1138 static void update_calls_to_private(ir_node *call, void *env) {
1140 if (is_Call(call)) {
1141 ir_node *ptr = get_Call_ptr(call);
1143 if (is_SymConst(ptr)) {
1144 ir_entity *ent = get_SymConst_entity(ptr);
1145 ir_type *ctp = get_Call_type(call);
1147 if (get_entity_additional_properties(ent) & mtp_property_private) {
1148 if ((get_method_additional_properties(ctp) & mtp_property_private) == 0) {
1149 ctp = clone_type_and_cache(ctp);
1150 set_method_additional_property(ctp, mtp_property_private);
1151 set_Call_type(call, ctp);
1152 DB((dbgcall, LEVEL_1, "changed call to private method %+F\n", ent));
1157 } /* update_calls_to_private */
1159 /* Mark all private methods, i.e. those of which all call sites are known. */
1160 void mark_private_methods(void) {
1164 FIRM_DBG_REGISTER(dbgcall, "firm.opt.cc");
1166 assure_irp_globals_address_taken_computed();
1168 mtp_map = pmap_create();
1170 /* first step: change the calling conventions of the local non-escaped entities */
1171 for (i = get_irp_n_irgs() - 1; i >= 0; --i) {
1172 ir_graph *irg = get_irp_irg(i);
1173 ir_entity *ent = get_irg_entity(irg);
1174 ir_address_taken_state state = get_entity_address_taken(ent);
1176 if (get_entity_visibility(ent) == visibility_local &&
1177 state == ir_address_not_taken) {
1178 ir_type *mtp = get_entity_type(ent);
1180 set_entity_additional_property(ent, mtp_property_private);
1181 DB((dbgcall, LEVEL_1, "found private method %+F\n", ent));
1182 if ((get_method_additional_properties(mtp) & mtp_property_private) == 0) {
1183 /* need a new type */
1184 mtp = clone_type_and_cache(mtp);
1185 set_entity_type(ent, mtp);
1186 set_method_additional_property(mtp, mtp_property_private);
1193 all_irg_walk(NULL, update_calls_to_private, NULL);
1195 pmap_destroy(mtp_map);
1196 } /* mark_private_methods */