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 Cliff Click's Combined Analysis/Optimization
23 * @author Michael Beck
26 * Note that we use the terminology from Click's work here, which is different
27 * in some cases from Firm terminology. Especially, Click's type is a
28 * Firm tarval, nevertheless we call it type here for "maximum compatibility".
36 #include "iroptimize.h"
44 #include "irgraph_t.h"
58 typedef struct node_t node_t;
59 typedef struct partition_t partition_t;
60 typedef struct opcode_key_t opcode_key_t;
61 typedef struct listmap_entry_t listmap_entry_t;
63 /** The type of the compute function. */
64 typedef void (*compute_func)(node_t *node);
70 ir_opcode code; /**< The Firm opcode. */
71 ir_mode *mode; /**< The mode of all nodes in the partition. */
72 long proj; /**< For Proj nodes, its proj number */
76 * An entry in the list_map.
78 struct listmap_entry_t {
79 void *id; /**< The id. */
80 node_t *list; /**< The associated list for this id. */
81 listmap_entry_t *next; /**< Link to the next entry in the map. */
84 /** We must map id's to lists. */
85 typedef struct listmap_t {
86 set *map; /**< Map id's to listmap_entry_t's */
87 listmap_entry_t *values; /**< List of all values in the map. */
91 * A lattice element. Because we handle constants and symbolic constants different, we
92 * have to use this union.
103 ir_node *node; /**< The IR-node itself. */
104 list_head node_list; /**< Double-linked list of entries. */
105 partition_t *part; /**< points to the partition this node belongs to */
106 node_t *cprop_next; /**< Next node on partition.cprop list. */
107 node_t *next; /**< Next node on local list (partition.touched, fallen). */
108 lattice_elem_t type; /**< The associated lattice element "type". */
109 int max_user_input; /**< Maximum input number of Def-Use edges. */
110 int next_edge; /**< Index of the next Def-Use edge to use. */
111 unsigned on_touched:1; /**< Set, if this node is on the partition.touched set. */
112 unsigned on_cprop:1; /**< Set, if this node is on the partition.cprop list. */
113 unsigned on_fallen:1; /**< Set, if this node is on the fallen list. */
117 * A partition containing congruent nodes.
120 list_head entries; /**< The head of partition node list. */
121 node_t *cprop; /**< The partition.cprop list. */
122 partition_t *wl_next; /**< Next entry in the work list if any. */
123 partition_t *touched_next; /**< Points to the next partition in the touched set. */
124 partition_t *cprop_next; /**< Points to the next partition in the cprop list. */
125 node_t *touched; /**< The partition.touched set of this partition. */
126 unsigned n_nodes; /**< Number of entries in this partition. */
127 unsigned n_touched; /**< Number of entries in the partition.touched. */
128 int max_arity; /**< Maximum arity of all entries. */
129 int max_user_inputs; /**< Maximum number of user inputs of all entries. */
130 unsigned on_worklist:1; /**< Set, if this partition is in the work list. */
131 unsigned on_touched:1; /**< Set, if this partition is on the touched set. */
132 unsigned on_cprop:1; /**< Set, if this partition is on the cprop list. */
134 partition_t *dbg_next; /**< Link all partitions for debugging */
135 unsigned nr; /**< A unique number for (what-)mapping, >0. */
139 typedef struct environment_t {
140 struct obstack obst; /**< obstack to allocate data structures. */
141 partition_t *worklist; /**< The work list. */
142 partition_t *cprop; /**< The constant propagation list. */
143 partition_t *touched; /**< the touched set. */
144 partition_t *initial; /**< The initial partition. */
146 partition_t *dbg_list; /**< List of all partitions. */
148 set *opcode2id_map; /**< The opcodeMode->id map. */
149 pmap *type2id_map; /**< The type->id map. */
150 int end_idx; /**< -1 for local and 0 for global congruences. */
151 int lambda_input; /**< Captured argument for lambda_partition(). */
154 /** Type of the what function. */
155 typedef void *(*what_func)(const node_t *node, environment_t *env);
157 #define get_irn_node(irn) ((node_t *)get_irn_link(irn))
158 #define set_irn_node(irn, node) set_irn_link(irn, node)
160 /** The debug module handle. */
161 DEBUG_ONLY(static firm_dbg_module_t *dbg;)
163 /** Next partition number. */
164 DEBUG_ONLY(static unsigned part_nr = 0);
167 static INLINE lattice_elem_t get_partition_type(const partition_t *X);
170 * Dump partition to output.
172 static void dump_partition(const char *msg, const partition_t *part) {
175 lattice_elem_t type = get_partition_type(part);
177 DB((dbg, LEVEL_2, "%s part%u (%u, %+F) {\n ", msg, part->nr, part->n_nodes, type));
178 list_for_each_entry(node_t, node, &part->entries, node_list) {
179 DB((dbg, LEVEL_2, "%s%+F", first ? "" : ", ", node->node));
182 DB((dbg, LEVEL_2, "\n}\n"));
186 * Dump all partitions.
188 static void dump_all_partitions(const environment_t *env) {
189 const partition_t *P;
191 DB((dbg, LEVEL_2, "All partitions\n===============\n"));
192 for (P = env->dbg_list; P != NULL; P = P->dbg_next)
193 dump_partition("", P);
197 #define dump_partition(msg, part)
198 #define dump_all_partitions(env)
202 * Compare two pointer values of a listmap.
204 static int listmap_cmp_ptr(const void *elt, const void *key, size_t size) {
205 const listmap_entry_t *e1 = elt;
206 const listmap_entry_t *e2 = key;
209 return e1->id != e2->id;
210 } /* listmap_cmp_ptr */
213 * Initializes a listmap.
215 * @param map the listmap
217 static void listmap_init(listmap_t *map) {
218 map->map = new_set(listmap_cmp_ptr, 16);
223 * Terminates a listmap.
225 * @param map the listmap
227 static void listmap_term(listmap_t *map) {
232 * Return the associated listmap entry for a given id.
234 * @param map the listmap
235 * @param id the id to search for
237 * @return the asociated listmap entry for the given id
239 static listmap_entry_t *listmap_find(listmap_t *map, void *id) {
240 listmap_entry_t key, *entry;
245 entry = set_insert(map->map, &key, sizeof(key), HASH_PTR(id));
247 if (entry->list == NULL) {
248 /* a new entry, put into the list */
249 entry->next = map->values;
256 * Calculate the hash value for an opcode map entry.
258 * @param entry an opcode map entry
260 * @return a hash value for the given opcode map entry
262 static unsigned opcode_hash(const opcode_key_t *entry) {
263 return (entry->mode - (ir_mode *)0) * 9 + entry->code + entry->proj * 3;
267 * Compare two entries in the opcode map.
269 static int cmp_opcode(const void *elt, const void *key, size_t size) {
270 const opcode_key_t *o1 = elt;
271 const opcode_key_t *o2 = key;
274 return o1->code != o2->code || o1->mode != o2->mode || o1->proj != o2->proj;
278 * Compare two Def-Use edges for input position.
280 static int cmp_def_use_edge(const void *a, const void *b) {
281 const ir_def_use_edge *ea = a;
282 const ir_def_use_edge *eb = b;
284 /* no overrun, because range is [-1, MAXINT] */
285 return ea->pos - eb->pos;
286 } /* cmp_def_use_edge */
289 * We need the Def-Use edges sorted.
291 static void sort_irn_outs(node_t *node) {
292 ir_node *irn = node->node;
293 int n_outs = get_irn_n_outs(irn);
296 qsort(&irn->out[1], n_outs, sizeof(irn->out[0]), cmp_def_use_edge);
298 node->max_user_input = irn->out[n_outs + 1].pos;
299 } /* sort_irn_outs */
302 * Return the type of a node.
304 * @param irn an IR-node
306 * @return the associated type of this node
308 static INLINE lattice_elem_t get_node_type(const ir_node *irn) {
309 return get_irn_node(irn)->type;
310 } /* get_node_type */
313 * Return the tarval of a node.
315 * @param irn an IR-node
317 * @return the associated type of this node
319 static INLINE tarval *get_node_tarval(const ir_node *irn) {
320 lattice_elem_t type = get_node_type(irn);
322 if (is_tarval(type.tv))
324 return tarval_bottom;
325 } /* get_node_type */
328 * Add a partition to the worklist.
330 static INLINE void add_to_worklist(partition_t *X, environment_t *env) {
331 assert(X->on_worklist == 0);
332 X->wl_next = env->worklist;
338 * Create a new empty partition.
340 * @param env the environment
342 * @return a newly allocated partition
344 static INLINE partition_t *new_partition(environment_t *env) {
345 partition_t *part = obstack_alloc(&env->obst, sizeof(*part));
347 INIT_LIST_HEAD(&part->entries);
349 part->wl_next = NULL;
350 part->touched_next = NULL;
351 part->cprop_next = NULL;
352 part->touched = NULL;
356 part->max_user_inputs = 0;
357 part->on_worklist = 0;
358 part->on_touched = 0;
361 part->dbg_next = env->dbg_list;
362 env->dbg_list = part;
363 part->nr = part_nr++;
367 } /* new_partition */
370 * Get the first node from a partition.
372 static INLINE node_t *get_first_node(const partition_t *X) {
373 return list_entry(X->entries.next, node_t, node_list);
377 * Return the type of a partition (assuming partition is non-empty and
378 * all elements have the same type).
380 * @param X a partition
382 * @return the type of the first element of the partition
384 static INLINE lattice_elem_t get_partition_type(const partition_t *X) {
385 const node_t *first = get_first_node(X);
387 } /* get_partition_type */
390 * Creates a partition node for the given IR-node and place it
391 * into the given partition.
393 * @param irn an IR-node
394 * @param part a partition to place the node in
395 * @param env the environment
397 * @return the created node
399 static node_t *create_partition_node(ir_node *irn, partition_t *part, environment_t *env) {
400 /* create a partition node and place it in the partition */
401 node_t *node = obstack_alloc(&env->obst, sizeof(*node));
402 ir_mode *mode = get_irn_mode(irn);
404 INIT_LIST_HEAD(&node->node_list);
407 node->cprop_next = NULL;
409 node->type.tv = (mode == mode_X || mode == mode_BB) ? tarval_unreachable : tarval_top;
410 node->max_user_input = 0;
412 node->on_touched = 0;
415 set_irn_node(irn, node);
417 list_add_tail(&node->node_list, &part->entries);
421 } /* create_partition_node */
424 * Walker, initialize all Nodes' type to U or top and place
425 * all nodes into the TOP partition.
427 static void create_initial_partitions(ir_node *irn, void *ctx) {
428 environment_t *env = ctx;
429 partition_t *part = env->initial;
433 node = create_partition_node(irn, part, env);
435 arity = get_irn_arity(irn);
436 if (arity > part->max_arity)
437 part->max_arity = arity;
438 if (node->max_user_input > part->max_user_inputs)
439 part->max_user_inputs = node->max_user_input;
440 } /* create_initial_partitions */
443 * Add a partition to the touched set if not already there.
445 * @param part the partition
446 * @param env the environment
448 static INLINE void add_to_touched(partition_t *part, environment_t *env) {
449 if (part->on_touched == 0) {
450 part->touched_next = env->touched;
452 part->on_touched = 1;
454 } /* add_to_touched */
457 * Add a node to the entry.partition.touched set if not already there.
461 static INLINE void add_to_partition_touched(node_t *y) {
462 if (y->on_touched == 0) {
463 partition_t *part = y->part;
465 y->next = part->touched;
470 } /* add_to_partition_touched */
473 * Update the worklist: If Z is on worklist then add Z' to worklist.
474 * Else add the smaller of Z and Z' to worklist.
476 * @param Z the Z partition
477 * @param Z_prime the Z' partition, a previous part of Z
478 * @param env the environment
480 static void update_worklist(partition_t *Z, partition_t *Z_prime, environment_t *env) {
481 if (Z->on_worklist || Z_prime->n_nodes < Z->n_nodes) {
482 add_to_worklist(Z_prime, env);
484 add_to_worklist(Z, env);
486 } /* update_worklist */
489 * Split a partition by a local list.
491 * @param Z the Z partition to split
492 * @param g a (non-empty) node list
493 * @param env the environment
495 * @return a new partition containing the nodes of g
497 static partition_t *split(partition_t *Z, node_t *g, environment_t *env) {
498 partition_t *Z_prime;
501 int max_input, max_arity, arity;
503 dump_partition("Splitting ", Z);
507 /* Remove g from Z. */
508 for (node = g; node != NULL; node = node->next) {
509 list_del(&node->node_list);
512 assert(n < Z->n_nodes);
515 /* Move g to a new partition, Z
\92. */
516 Z_prime = new_partition(env);
517 max_arity = max_input = 0;
518 for (node = g; node != NULL; node = node->next) {
519 list_add(&node->node_list, &Z_prime->entries);
520 node->part = Z_prime;
521 arity = get_irn_arity(node->node);
522 if (arity > max_arity)
524 if (node->max_user_input > max_input)
525 max_input = node->max_user_input;
527 Z_prime->max_arity = max_arity;
528 Z_prime->max_user_inputs = max_input;
529 Z_prime->n_nodes = n;
531 update_worklist(Z, Z_prime, env);
533 dump_partition("Now ", Z);
534 dump_partition("Created new ", Z_prime);
539 * Returns non-zero if the i'th input of a Phi node is live.
541 * @param phi a Phi-node
542 * @param i an input number
544 * @return non-zero if the i'th input of the given Phi node is live
546 static int is_live_input(ir_node *phi, int i) {
548 ir_node *block = get_nodes_block(phi);
549 ir_node *pred = get_Block_cfgpred(block, i);
550 lattice_elem_t type = get_node_type(pred);
552 return type.tv != tarval_unreachable;
554 /* else it's the control input, always live */
556 } /* is_live_input */
559 * Return non-zero if a type is a constant.
561 static int is_constant_type(lattice_elem_t type) {
562 if (type.tv != tarval_bottom && type.tv != tarval_top)
565 } /* is_constant_type */
568 * Place a node on the cprop list.
571 * @param env the environment
573 static void add_node_to_cprop(node_t *y, environment_t *env) {
574 /* Add y to y.partition.cprop. */
575 if (y->on_cprop == 0) {
576 partition_t *Y = y->part;
578 y->cprop_next = Y->cprop;
582 DB((dbg, LEVEL_3, "Add %+F to part%u.cprop\n", y->node, Y->nr));
584 /* place its partition on the cprop list */
585 if (Y->on_cprop == 0) {
586 Y->cprop_next = env->cprop;
591 if (get_irn_mode(y->node) == mode_T) {
592 /* mode_T nodes always produce tarval_bottom, so we must explicitly
593 add it's Proj's to get constant evaluation to work */
596 for (i = get_irn_n_outs(y->node) - 1; i >= 0; --i) {
597 node_t *proj = get_irn_node(get_irn_out(y->node, i));
599 add_node_to_cprop(proj, env);
602 } /* add_node_to_cprop */
605 * Split the partitions if caused by the first entry on the worklist.
607 * @param env the environment
609 static void cause_splits(environment_t *env) {
610 partition_t *X, *Y, *Z;
616 /* remove the first partition from the worklist */
618 env->worklist = X->wl_next;
621 dump_partition("Cause_split: ", X);
622 end_idx = env->end_idx;
623 for (i = -1; i <= X->max_user_inputs; ++i) {
624 /* empty the touched set: already done, just clear the list */
627 list_for_each_entry(node_t, x, &X->entries, node_list) {
633 num_edges = get_irn_n_outs(x->node);
635 while (x->next_edge <= num_edges) {
636 ir_def_use_edge *edge = &x->node->out[x->next_edge];
638 /* check if we have necessary edges */
646 /* ignore the "control input" for non-pinned nodes
647 if we are running in GCSE mode */
648 if (i < end_idx && get_irn_pinned(succ) != op_pin_state_pinned)
651 y = get_irn_node(succ);
652 if (is_constant_type(y->type)) {
653 code = get_irn_opcode(succ);
654 if (code == iro_Sub || (code == iro_Proj && is_Cmp(get_Proj_pred(succ))))
655 add_node_to_cprop(y, env);
658 /* Partitions of constants should not be split simply because their Nodes have unequal
659 functions or incongruent inputs. */
660 if (y->type.tv == tarval_bottom &&
661 (! is_Phi(x->node) || is_live_input(x->node, i))) {
663 add_to_touched(Y, env);
664 add_to_partition_touched(y);
669 for (Z = env->touched; Z != NULL; Z = Z->touched_next) {
670 /* remove it from the touched set */
673 if (Z->n_nodes != Z->n_touched) {
674 split(Z, Z->touched, env);
676 /* Empty local Z.touched. */
677 for (e = Z->touched; e != NULL; e = e->next) {
687 * Implements split_by_what(): Split a partition by characteristics given
688 * by the what function.
690 * @param X the partition to split
691 * @param What a function returning an Id for every node of the partition X
692 * @param P an flexible array to store the result partitions or NULL
693 * @param env the environment
695 * @return if P != NULL P will be filled with the resulting partitions and returned
697 static partition_t **split_by_what(partition_t *X, what_func What,
698 partition_t **P, environment_t *env) {
701 listmap_entry_t *iter;
704 /* Let map be an empty mapping from the range of What to (local) list of Nodes. */
706 list_for_each_entry(node_t, x, &X->entries, node_list) {
707 void *id = What(x, env);
708 listmap_entry_t *entry;
711 /* input not allowed, ignore */
714 /* Add x to map[What(x)]. */
715 entry = listmap_find(&map, id);
716 x->next = entry->list;
719 /* Let P be a set of Partitions. */
721 /* for all sets S except one in the range of map do */
722 for (iter = map.values; iter != NULL; iter = iter->next) {
723 if (iter->next == NULL) {
724 /* this is the last entry, ignore */
729 /* Add SPLIT( X, S ) to P. */
730 R = split(X, S, env);
732 ARR_APP1(partition_t *, P, R);
737 ARR_APP1(partition_t *, P, X);
742 } /* split_by_what */
744 /** lambda n.(n.type) */
745 static void *lambda_type(const node_t *node, environment_t *env) {
747 return node->type.tv;
750 /** lambda n.(n.opcode) */
751 static void *lambda_opcode(const node_t *node, environment_t *env) {
752 opcode_key_t key, *entry;
753 ir_node *irn = node->node;
755 key.code = get_irn_opcode(irn);
756 key.mode = get_irn_mode(irn);
757 key.proj = is_Proj(irn) ? get_Proj_proj(irn) : 0;
758 entry = set_insert(env->opcode2id_map, &key, sizeof(key), opcode_hash(&key));
760 } /* lambda_opcode */
762 /** lambda n.(n[i].partition) */
763 static void *lambda_partition(const node_t *node, environment_t *env) {
766 int i = env->lambda_input;
768 if (i >= get_irn_arity(node->node)) {
769 /* we are outside the allowed range */
773 /* ignore the "control input" for non-pinned nodes
774 if we are running in GCSE mode */
775 if (i < env->end_idx && get_irn_pinned(node->node) != op_pin_state_pinned)
778 pred = get_irn_n(node->node, i);
779 p = get_irn_node(pred);
782 } /* lambda_partition */
785 * Checks whether a type is a constant.
787 static int is_type_constant(lattice_elem_t type) {
788 if (is_tarval(type.tv))
789 return tarval_is_constant(type.tv);
790 /* else it is a symconst */
795 * Implements split_by().
797 * @param X the partition to split
798 * @param env the environment
800 static void split_by(partition_t *X, environment_t *env) {
801 partition_t **P = NEW_ARR_F(partition_t *, 0);
804 P = split_by_what(X, lambda_type, P, env);
805 for (i = ARR_LEN(P) - 1; i >= 0; --i) {
806 partition_t *Y = P[i];
808 if (Y->n_nodes > 1) {
809 lattice_elem_t type = get_partition_type(Y);
811 /* we do not want split the TOP, unreachable or constant partitions */
812 if (type.tv != tarval_top && type.tv != tarval_unreachable && !is_type_constant(type)) {
813 partition_t **Q = NEW_ARR_F(partition_t *, 0);
815 Q = split_by_what(Y, lambda_opcode, Q, env);
817 for (j = ARR_LEN(Q) - 1; j >= 0; --j) {
818 partition_t *Z = Q[j];
820 for (k = Z->max_arity - 1; k >= -1; --k) {
821 if (Z->n_nodes > 1) {
822 env->lambda_input = k;
823 split_by_what(Z, lambda_partition, NULL, env);
835 * (Re-)compute the type for a given node.
837 * @param node the node
839 static void default_compute(node_t *node) {
841 ir_node *irn = node->node;
842 tarval *top = tarval_top;
844 if (get_irn_mode(node->node) == mode_X)
845 top = tarval_unreachable;
847 if (get_irn_pinned(irn) == op_pin_state_pinned) {
848 node_t *block = get_irn_node(get_nodes_block(irn));
850 if (block->type.tv == tarval_unreachable) {
856 /* if any of the data inputs have type top, the result is type top */
857 for (i = get_irn_arity(irn) - 1; i >= 0; --i) {
858 ir_node *pred = get_irn_n(irn, i);
859 node_t *p = get_irn_node(pred);
861 if (p->type.tv == tarval_top) {
867 if (get_irn_mode(node->node) == mode_X)
868 node->type.tv = tarval_reachable;
870 node->type.tv = computed_value(irn);
871 } /* default_compute */
874 * (Re-)compute the type for a Block node.
876 * @param node the node
878 static void compute_Block(node_t *node) {
880 ir_node *block = node->node;
882 for (i = get_Block_n_cfgpreds(block) - 1; i >= 0; --i) {
883 node_t *pred = get_irn_node(get_Block_cfgpred(block, i));
885 if (pred->type.tv == tarval_reachable) {
886 /* A block is reachable, if at least of predecessor is reachable. */
887 node->type.tv = tarval_reachable;
891 node->type.tv = tarval_unreachable;
892 } /* compute_Block */
895 * (Re-)compute the type for a Jmp node.
897 * @param node the node
899 static void compute_Jmp(node_t *node) {
900 node_t *block = get_irn_node(get_nodes_block(node->node));
902 node->type = block->type;
906 * (Re-)compute the type for the End node.
908 * @param node the node
910 static void compute_End(node_t *node) {
911 /* the End node is NOT dead of course */
912 node->type.tv = tarval_reachable;
916 * (Re-)compute the type for a SymConst node.
918 * @param node the node
920 static void compute_SymConst(node_t *node) {
921 ir_node *irn = node->node;
922 node_t *block = get_irn_node(get_nodes_block(irn));
924 if (block->type.tv == tarval_unreachable) {
925 node->type.tv = tarval_top;
928 switch (get_SymConst_kind(irn)) {
929 case symconst_addr_ent:
930 /* case symconst_addr_name: cannot handle this yet */
931 node->type.sym = get_SymConst_symbol(irn);
934 node->type.tv = computed_value(irn);
936 } /* compute_SymConst */
939 * (Re-)compute the type for a Phi node.
941 * @param node the node
943 static void compute_Phi(node_t *node) {
945 ir_node *phi = node->node;
948 /* if a Phi is in a unreachable block, its type is TOP */
949 node_t *block = get_irn_node(get_nodes_block(phi));
951 if (block->type.tv == tarval_unreachable) {
952 node->type.tv = tarval_top;
956 /* Phi implements the Meet operation */
957 type.tv = tarval_top;
958 for (i = get_Phi_n_preds(phi) - 1; i >= 0; --i) {
959 node_t *pred = get_irn_node(get_Phi_pred(phi, i));
960 node_t *pred_X = get_irn_node(get_Block_cfgpred(block->node, i));
962 if (pred_X->type.tv == tarval_unreachable || pred->type.tv == tarval_top) {
963 /* ignore TOP inputs: We must check here for unreachable blocks,
964 because Firm constants live in the Start Block are NEVER Top.
965 Else, a Phi (1,2) will produce Bottom, even if the 2 for instance
966 comes from a unreachable input. */
969 if (pred->type.tv == tarval_bottom) {
970 node->type.tv = tarval_bottom;
972 } else if (type.tv == tarval_top) {
973 /* first constant found */
975 } else if (type.tv != pred->type.tv) {
976 /* different constants or tarval_bottom */
977 node->type.tv = tarval_bottom;
980 /* else nothing, constants are the same */
986 * (Re-)compute the type for an Add. Special case: one nodes is a Zero Const.
988 * @param node the node
990 static void compute_Add(node_t *node) {
991 ir_node *sub = node->node;
992 node_t *l = get_irn_node(get_Add_left(sub));
993 node_t *r = get_irn_node(get_Add_right(sub));
994 lattice_elem_t a = l->type;
995 lattice_elem_t b = r->type;
996 node_t *block = get_irn_node(get_nodes_block(sub));
999 if (block->type.tv == tarval_unreachable) {
1000 node->type.tv = tarval_top;
1004 if (a.tv == tarval_top || b.tv == tarval_top) {
1005 node->type.tv = tarval_top;
1006 } else if (a.tv == tarval_bottom || b.tv == tarval_bottom) {
1007 node->type.tv = tarval_bottom;
1009 /* x + 0 = 0 + x = x, but beware of floating point +0 + -0, so we
1010 must call tarval_add() first to handle this case! */
1011 if (is_tarval(a.tv)) {
1012 if (is_tarval(b.tv)) {
1013 node->type.tv = tarval_add(a.tv, b.tv);
1016 mode = get_tarval_mode(a.tv);
1017 if (a.tv == get_mode_null(mode)) {
1021 } else if (is_tarval(b.tv)) {
1022 mode = get_tarval_mode(b.tv);
1023 if (b.tv == get_mode_null(mode)) {
1028 node->type.tv = tarval_bottom;
1033 * (Re-)compute the type for a Sub. Special case: both nodes are congruent.
1035 * @param node the node
1037 static void compute_Sub(node_t *node) {
1038 ir_node *sub = node->node;
1039 node_t *l = get_irn_node(get_Sub_left(sub));
1040 node_t *r = get_irn_node(get_Sub_right(sub));
1041 lattice_elem_t a = l->type;
1042 lattice_elem_t b = r->type;
1043 node_t *block = get_irn_node(get_nodes_block(sub));
1045 if (block->type.tv == tarval_unreachable) {
1046 node->type.tv = tarval_top;
1050 if (a.tv == tarval_top || b.tv == tarval_top) {
1051 node->type.tv = tarval_top;
1052 } else if (r->part == l->part) {
1053 ir_mode *mode = get_irn_mode(sub);
1054 node->type.tv = get_mode_null(mode);
1055 } else if (a.tv == tarval_bottom || b.tv == tarval_bottom) {
1056 node->type.tv = tarval_bottom;
1058 if (is_tarval(a.tv) && is_tarval(b.tv))
1059 node->type.tv = tarval_sub(a.tv, b.tv);
1061 node->type.tv = tarval_bottom;
1066 * (Re-)compute the type for a Proj(Cmp).
1068 * @param node the node
1069 * @param cond the predecessor Cmp node
1071 static void compute_Proj_Cmp(node_t *node, ir_node *cmp) {
1072 ir_node *proj = node->node;
1073 node_t *l = get_irn_node(get_Cmp_left(cmp));
1074 node_t *r = get_irn_node(get_Cmp_right(cmp));
1075 lattice_elem_t a = l->type;
1076 lattice_elem_t b = r->type;
1077 pn_Cmp pnc = get_Proj_proj(proj);
1080 * BEWARE: a == a is NOT always True for floating Point values, as
1081 * NaN != NaN is defined, so we must check this here.
1083 if (!mode_is_float(get_irn_mode(l->node)) || pnc == pn_Cmp_Lt || pnc == pn_Cmp_Gt) {
1084 if (a.tv == tarval_top || b.tv == tarval_top) {
1085 node->type.tv = tarval_top;
1086 } else if (r->part == l->part) {
1087 node->type.tv = new_tarval_from_long(pnc & pn_Cmp_Eq, mode_b);
1088 } else if (a.tv == tarval_bottom || b.tv == tarval_bottom) {
1089 node->type.tv = tarval_bottom;
1091 default_compute(node);
1094 default_compute(node);
1096 } /* compute_Proj_Cmp */
1099 * (Re-)compute the type for a Proj(Cond).
1101 * @param node the node
1102 * @param cond the predecessor Cond node
1104 static void compute_Proj_Cond(node_t *node, ir_node *cond) {
1105 ir_node *proj = node->node;
1106 long pnc = get_Proj_proj(proj);
1107 ir_node *sel = get_Cond_selector(cond);
1108 node_t *selector = get_irn_node(sel);
1110 if (get_irn_mode(sel) == mode_b) {
1112 if (pnc == pn_Cond_true) {
1113 if (selector->type.tv == tarval_b_false) {
1114 node->type.tv = tarval_unreachable;
1115 } else if (selector->type.tv == tarval_b_true) {
1116 node->type.tv = tarval_reachable;
1117 } else if (selector->type.tv == tarval_bottom) {
1118 node->type.tv = tarval_reachable;
1120 assert(selector->type.tv == tarval_top);
1121 node->type.tv = tarval_unreachable;
1124 assert(pnc == pn_Cond_false);
1126 if (selector->type.tv == tarval_b_false) {
1127 node->type.tv = tarval_reachable;
1128 } else if (selector->type.tv == tarval_b_true) {
1129 node->type.tv = tarval_unreachable;
1130 } else if (selector->type.tv == tarval_bottom) {
1131 node->type.tv = tarval_reachable;
1133 assert(selector->type.tv == tarval_top);
1134 node->type.tv = tarval_unreachable;
1139 if (selector->type.tv == tarval_bottom) {
1140 node->type.tv = tarval_reachable;
1141 } else if (selector->type.tv == tarval_top) {
1142 node->type.tv = tarval_unreachable;
1144 long value = get_tarval_long(selector->type.tv);
1145 if (pnc == get_Cond_defaultProj(cond)) {
1146 /* default switch, have to check ALL other cases */
1149 for (i = get_irn_n_outs(cond) - 1; i >= 0; --i) {
1150 ir_node *succ = get_irn_out(cond, i);
1154 if (value == get_Proj_proj(succ)) {
1155 /* we found a match, will NOT take the default case */
1156 node->type.tv = tarval_unreachable;
1160 /* all cases checked, no match, will take default case */
1161 node->type.tv = tarval_reachable;
1164 node->type.tv = value == pnc ? tarval_reachable : tarval_unreachable;
1168 } /* compute_Proj_Cond */
1171 * (Re-)compute the type for a Proj-Nodes.
1173 * @param node the node
1175 static void compute_Proj(node_t *node) {
1176 ir_node *proj = node->node;
1177 ir_mode *mode = get_irn_mode(proj);
1180 if (mode == mode_M) {
1181 /* mode M is always bottom */
1182 node->type.tv = tarval_bottom;
1185 if (mode != mode_X) {
1186 ir_node *cmp = get_Proj_pred(proj);
1188 compute_Proj_Cmp(node, cmp);
1190 default_compute(node);
1193 /* handle mode_X nodes */
1194 pred = get_Proj_pred(proj);
1196 switch (get_irn_opcode(pred)) {
1198 /* the Proj_X from the Start is always reachable */
1199 node->type.tv = tarval_reachable;
1202 compute_Proj_Cond(node, pred);
1205 default_compute(node);
1207 } /* compute_Proj */
1210 * (Re-)compute the type for a given node.
1212 * @param node the node
1214 static void compute(node_t *node) {
1215 compute_func func = (compute_func)node->node->op->ops.generic;
1222 * Propagate constant evaluation.
1224 * @param env the environment
1226 static void propagate(environment_t *env) {
1229 lattice_elem_t old_type;
1234 while (env->cprop != NULL) {
1235 /* remove the first partition X from cprop */
1238 env->cprop = X->cprop_next;
1242 while (X->cprop != NULL) {
1243 /* remove the first Node x from X.cprop */
1246 X->cprop = x->cprop_next;
1248 /* compute a new type for x */
1250 DB((dbg, LEVEL_3, "computing type of %+F\n", x->node));
1252 if (x->type.tv != old_type.tv) {
1253 DB((dbg, LEVEL_2, "node %+F has changed type from %+F to %+F\n", x->node, old_type, x->type));
1255 if (x->on_fallen == 0) {
1256 /* Add x to fallen. Nodes might fall from T -> const -> _|_, so check that they are
1257 not already on the list. */
1263 for (i = get_irn_n_outs(x->node) - 1; i >= 0; --i) {
1264 ir_node *succ = get_irn_out(x->node, i);
1265 node_t *y = get_irn_node(succ);
1267 /* Add y to y.partition.cprop. */
1268 add_node_to_cprop(y, env);
1273 if (n_fallen > 0 && n_fallen != X->n_nodes) {
1274 Y = split(X, fallen, env);
1278 /* remove the nodes from the fallen list */
1279 for (x = fallen; x != NULL; x = x->next)
1288 * Get the leader for a given node from its congruence class.
1290 * @param irn the node
1292 static ir_node *get_leader(node_t *node) {
1293 partition_t *part = node->part;
1295 if (part->n_nodes > 1) {
1296 DB((dbg, LEVEL_2, "Found congruence class for %+F\n", node->node));
1298 return get_first_node(part)->node;
1304 * Post-Walker, apply the analysis results;
1306 static void apply_result(ir_node *irn, void *ctx) {
1307 node_t *node = get_irn_node(irn);
1310 if (is_Block(irn)) {
1311 if (irn == get_irg_end_block(current_ir_graph)) {
1312 /* the EndBlock is always reachable even if the analysis
1313 finds out the opposite :-) */
1317 if (node->type.tv == tarval_unreachable) {
1318 /* mark dead blocks */
1319 set_Block_dead(irn);
1321 } else if (is_End(irn)) {
1322 /* do not touch the End node */
1324 node_t *block = get_irn_node(get_nodes_block(irn));
1326 if (block->type.tv == tarval_unreachable) {
1327 ir_node *bad = get_irg_bad(current_ir_graph);
1329 /* here, bad might already have a node, but this can be safely ignored
1330 as long as bad has at least ONE valid node */
1331 set_irn_node(bad, node);
1333 DB((dbg, LEVEL_1, "%+F is unreachable\n", irn));
1336 else if (get_irn_mode(irn) == mode_X) {
1337 if (node->type.tv == tarval_unreachable) {
1338 ir_node *bad = get_irg_bad(current_ir_graph);
1340 /* see comment above */
1341 set_irn_node(bad, node);
1343 DB((dbg, LEVEL_1, "%+F is unreachable\n", irn));
1344 exchange(irn, get_irg_bad(current_ir_graph));
1346 else if (is_Proj(irn)) {
1348 ir_node *cond = get_Proj_pred(irn);
1350 if (is_Cond(cond)) {
1351 node_t *sel = get_irn_node(get_Cond_selector(cond));
1353 if (is_tarval(sel->type.tv) && tarval_is_constant(sel->type.tv)) {
1354 /* Cond selector is a constant, make a Jmp */
1355 ir_node *jmp = new_r_Jmp(current_ir_graph, block->node);
1356 set_irn_node(jmp, node);
1358 DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", irn, jmp));
1364 /* normal data node */
1365 if (is_tarval(node->type.tv) && tarval_is_constant(node->type.tv)) {
1366 tarval *tv = node->type.tv;
1368 if (! is_Const(irn)) {
1369 /* can be replaced by a constant */
1370 ir_node *c = new_r_Const(current_ir_graph, block->node, get_tarval_mode(tv), tv);
1371 set_irn_node(c, node);
1373 DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", irn, c));
1376 } else if (is_entity(node->type.sym.entity_p)) {
1377 if (! is_SymConst(irn)) {
1378 /* can be replaced by a Symconst */
1379 ir_node *symc = new_r_SymConst(current_ir_graph, block->node, get_irn_mode(irn), node->type.sym, symconst_addr_ent);
1380 set_irn_node(symc, node);
1383 DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", irn, symc));
1384 exchange(irn, symc);
1387 ir_node *leader = get_leader(node);
1389 if (leader != irn) {
1390 DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", irn, leader));
1391 exchange(irn, leader);
1396 } /* static void apply_result(ir_node *irn, void *ctx) {
1399 #define SET(code) op_##code->ops.generic = (op_func)compute_##code
1402 * sets the generic functions to compute.
1404 static void set_compute_functions(void) {
1407 /* set the default compute function */
1408 for (i = get_irp_n_opcodes() - 1; i >= 0; --i) {
1409 ir_op *op = get_irp_opcode(i);
1410 op->ops.generic = (op_func)default_compute;
1413 /* set specific functions */
1422 } /* set_compute_functions */
1424 static int dump_partition_hook(FILE *F, ir_node *n, ir_node *local) {
1425 ir_node *irn = local != NULL ? local : n;
1426 node_t *node = get_irn_node(irn);
1428 ir_fprintf(F, "info2 : \"partition %u type %+F\"\n", node->part->nr, node->type);
1432 void combo(ir_graph *irg) {
1436 ir_graph *rem = current_ir_graph;
1438 current_ir_graph = irg;
1440 /* register a debug mask */
1441 FIRM_DBG_REGISTER(dbg, "firm.opt.combo");
1443 DB((dbg, LEVEL_1, "Doing COMBO for %+F\n", irg));
1445 obstack_init(&env.obst);
1446 env.worklist = NULL;
1450 #ifdef DEBUG_libfirm
1451 env.dbg_list = NULL;
1453 env.opcode2id_map = new_set(cmp_opcode, iro_Last * 4);
1454 env.type2id_map = pmap_create();
1455 env.end_idx = get_opt_global_cse() ? 0 : -1;
1456 env.lambda_input = 0;
1458 assure_irg_outs(irg);
1460 /* we have our own value_of function */
1461 set_value_of_func(get_node_tarval);
1463 set_compute_functions();
1465 /* create the initial partition and place it on the work list */
1466 env.initial = new_partition(&env);
1467 add_to_worklist(env.initial, &env);
1468 irg_walk_graph(irg, NULL, create_initial_partitions, &env);
1470 /* Place the START Node's partition on cprop.
1471 Place the START Node on its local worklist. */
1472 initial_X = get_irg_initial_exec(irg);
1473 start = get_irn_node(initial_X);
1474 add_node_to_cprop(start, &env);
1478 if (env.worklist != NULL)
1480 } while (env.cprop != NULL || env.worklist != NULL);
1482 dump_all_partitions(&env);
1484 set_dump_node_vcgattr_hook(dump_partition_hook);
1485 dump_ir_block_graph(irg, "-partition");
1486 set_dump_node_vcgattr_hook(NULL);
1489 /* apply the result */
1490 irg_walk_graph(irg, NULL, apply_result, &env);
1492 pmap_destroy(env.type2id_map);
1493 del_set(env.opcode2id_map);
1494 obstack_free(&env.obst, NULL);
1496 /* restore value_of() default behavior */
1497 set_value_of_func(NULL);
1498 current_ir_graph = rem;