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 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;
208 return e1->id != e2->id;
209 } /* listmap_cmp_ptr */
212 * Initializes a listmap.
214 * @param map the listmap
216 static void listmap_init(listmap_t *map) {
217 map->map = new_set(listmap_cmp_ptr, 16);
222 * Terminates a listmap.
224 * @param map the listmap
226 static void listmap_term(listmap_t *map) {
231 * Return the associated listmap entry for a given id.
233 * @param map the listmap
234 * @param id the id to search for
236 * @return the asociated listmap entry for the given id
238 static listmap_entry_t *listmap_find(listmap_t *map, void *id) {
239 listmap_entry_t key, *entry;
244 entry = set_insert(map->map, &key, sizeof(key), HASH_PTR(id));
246 if (entry->list == NULL) {
247 /* a new entry, put into the list */
248 entry->next = map->values;
255 * Calculate the hash value for an opcode map entry.
257 * @param entry an opcode map entry
259 * @return a hash value for the given opcode map entry
261 static unsigned opcode_hash(const opcode_key_t *entry) {
262 return (entry->mode - (ir_mode *)0) * 9 + entry->code + entry->proj * 3;
266 * Compare two entries in the opcode map.
268 static int cmp_opcode(const void *elt, const void *key, size_t size) {
269 const opcode_key_t *o1 = elt;
270 const opcode_key_t *o2 = key;
272 return o1->code != o2->code || o1->mode != o2->mode || o1->proj != o2->proj;
276 * Compare two Def-Use edges for input position.
278 static int cmp_def_use_edge(const void *a, const void *b) {
279 const ir_def_use_edge *ea = a;
280 const ir_def_use_edge *eb = b;
282 /* no overrun, because range is [-1, MAXINT] */
283 return ea->pos - eb->pos;
284 } /* cmp_def_use_edge */
287 * We need the Def-Use edges sorted.
289 static void sort_irn_outs(node_t *node) {
290 ir_node *irn = node->node;
291 int n_outs = get_irn_n_outs(irn);
294 qsort(&irn->out[1], n_outs, sizeof(irn->out[0]), cmp_def_use_edge);
296 node->max_user_input = irn->out[n_outs + 1].pos;
297 } /* sort_irn_outs */
300 * Return the type of a node.
302 * @param irn an IR-node
304 * @return the associated type of this node
306 static INLINE lattice_elem_t get_node_type(const ir_node *irn) {
307 return get_irn_node(irn)->type;
308 } /* get_node_type */
311 * Return the tarval of a node.
313 * @param irn an IR-node
315 * @return the associated type of this node
317 static INLINE tarval *get_node_tarval(const ir_node *irn) {
318 lattice_elem_t type = get_node_type(irn);
320 if (is_tarval(type.tv))
322 return tarval_bottom;
323 } /* get_node_type */
326 * Add a partition to the worklist.
328 static INLINE void add_to_worklist(partition_t *X, environment_t *env) {
329 assert(X->on_worklist == 0);
330 X->wl_next = env->worklist;
336 * Create a new empty partition.
338 * @param env the environment
340 * @return a newly allocated partition
342 static INLINE partition_t *new_partition(environment_t *env) {
343 partition_t *part = obstack_alloc(&env->obst, sizeof(*part));
345 INIT_LIST_HEAD(&part->entries);
347 part->wl_next = NULL;
348 part->touched_next = NULL;
349 part->cprop_next = NULL;
350 part->touched = NULL;
354 part->max_user_inputs = 0;
355 part->on_worklist = 0;
356 part->on_touched = 0;
359 part->dbg_next = env->dbg_list;
360 env->dbg_list = part;
361 part->nr = part_nr++;
365 } /* new_partition */
368 * Get the first node from a partition.
370 static INLINE node_t *get_first_node(const partition_t *X) {
371 return list_entry(X->entries.next, node_t, node_list);
375 * Return the type of a partition (assuming partition is non-empty and
376 * all elements have the same type).
378 * @param X a partition
380 * @return the type of the first element of the partition
382 static INLINE lattice_elem_t get_partition_type(const partition_t *X) {
383 const node_t *first = get_first_node(X);
385 } /* get_partition_type */
388 * Creates a partition node for the given IR-node and place it
389 * into the given partition.
391 * @param irn an IR-node
392 * @param part a partition to place the node in
393 * @param env the environment
395 * @return the created node
397 static node_t *create_partition_node(ir_node *irn, partition_t *part, environment_t *env) {
398 /* create a partition node and place it in the partition */
399 node_t *node = obstack_alloc(&env->obst, sizeof(*node));
400 ir_mode *mode = get_irn_mode(irn);
402 INIT_LIST_HEAD(&node->node_list);
405 node->cprop_next = NULL;
407 node->type.tv = (mode == mode_X || mode == mode_BB) ? tarval_unreachable : tarval_top;
408 node->max_user_input = 0;
410 node->on_touched = 0;
413 set_irn_node(irn, node);
415 list_add_tail(&node->node_list, &part->entries);
419 } /* create_partition_node */
422 * Walker, initialize all Nodes' type to U or top and place
423 * all nodes into the TOP partition.
425 static void create_initial_partitions(ir_node *irn, void *ctx) {
426 environment_t *env = ctx;
427 partition_t *part = env->initial;
431 node = create_partition_node(irn, part, env);
433 arity = get_irn_arity(irn);
434 if (arity > part->max_arity)
435 part->max_arity = arity;
436 if (node->max_user_input > part->max_user_inputs)
437 part->max_user_inputs = node->max_user_input;
438 } /* create_initial_partitions */
441 * Add a partition to the touched set if not already there.
443 * @param part the partition
444 * @param env the environment
446 static INLINE void add_to_touched(partition_t *part, environment_t *env) {
447 if (part->on_touched == 0) {
448 part->touched_next = env->touched;
450 part->on_touched = 1;
452 } /* add_to_touched */
455 * Add a node to the entry.partition.touched set if not already there.
459 static INLINE void add_to_partition_touched(node_t *y) {
460 if (y->on_touched == 0) {
461 partition_t *part = y->part;
463 y->next = part->touched;
468 } /* add_to_partition_touched */
471 * Update the worklist: If Z is on worklist then add Z' to worklist.
472 * Else add the smaller of Z and Z' to worklist.
474 * @param Z the Z partition
475 * @param Z_prime the Z' partition, a previous part of Z
476 * @param env the environment
478 static void update_worklist(partition_t *Z, partition_t *Z_prime, environment_t *env) {
479 if (Z->on_worklist || Z_prime->n_nodes < Z->n_nodes) {
480 add_to_worklist(Z_prime, env);
482 add_to_worklist(Z, env);
484 } /* update_worklist */
487 * Split a partition by a local list.
489 * @param Z the Z partition to split
490 * @param g a (non-empty) node list
491 * @param env the environment
493 * @return a new partition containing the nodes of g
495 static partition_t *split(partition_t *Z, node_t *g, environment_t *env) {
496 partition_t *Z_prime;
499 int max_input, max_arity, arity;
501 dump_partition("Splitting ", Z);
505 /* Remove g from Z. */
506 for (node = g; node != NULL; node = node->next) {
507 list_del(&node->node_list);
510 assert(n < Z->n_nodes);
513 /* Move g to a new partition, Z
\92. */
514 Z_prime = new_partition(env);
515 max_arity = max_input = 0;
516 for (node = g; node != NULL; node = node->next) {
517 list_add(&node->node_list, &Z_prime->entries);
518 node->part = Z_prime;
519 arity = get_irn_arity(node->node);
520 if (arity > max_arity)
522 if (node->max_user_input > max_input)
523 max_input = node->max_user_input;
525 Z_prime->max_arity = max_arity;
526 Z_prime->max_user_inputs = max_input;
527 Z_prime->n_nodes = n;
529 update_worklist(Z, Z_prime, env);
531 dump_partition("Now ", Z);
532 dump_partition("Created new ", Z_prime);
537 * Returns non-zero if the i'th input of a Phi node is live.
539 * @param phi a Phi-node
540 * @param i an input number
542 * @return non-zero if the i'th input of the given Phi node is live
544 static int is_live_input(ir_node *phi, int i) {
546 ir_node *block = get_nodes_block(phi);
547 ir_node *pred = get_Block_cfgpred(block, i);
548 lattice_elem_t type = get_node_type(pred);
550 return type.tv != tarval_unreachable;
552 /* else it's the control input, always live */
554 } /* is_live_input */
557 * Return non-zero if a type is a constant.
559 static int is_constant_type(lattice_elem_t type) {
560 if (type.tv != tarval_bottom && type.tv != tarval_top)
563 } /* is_constant_type */
566 * Place a node on the cprop list.
569 * @param env the environment
571 static void add_node_to_cprop(node_t *y, environment_t *env) {
572 /* Add y to y.partition.cprop. */
573 if (y->on_cprop == 0) {
574 partition_t *Y = y->part;
576 y->cprop_next = Y->cprop;
580 DB((dbg, LEVEL_3, "Add %+F to part%u.cprop\n", y->node, Y->nr));
582 /* place its partition on the cprop list */
583 if (Y->on_cprop == 0) {
584 Y->cprop_next = env->cprop;
589 if (get_irn_mode(y->node) == mode_T) {
590 /* mode_T nodes always produce tarval_bottom, so we must explicitly
591 add it's Proj's to get constant evaluation to work */
594 for (i = get_irn_n_outs(y->node) - 1; i >= 0; --i) {
595 node_t *proj = get_irn_node(get_irn_out(y->node, i));
597 add_node_to_cprop(proj, env);
600 } /* add_node_to_cprop */
603 * Split the partitions if caused by the first entry on the worklist.
605 * @param env the environment
607 static void cause_splits(environment_t *env) {
608 partition_t *X, *Y, *Z;
614 /* remove the first partition from the worklist */
616 env->worklist = X->wl_next;
619 dump_partition("Cause_split: ", X);
620 end_idx = env->end_idx;
621 for (i = -1; i <= X->max_user_inputs; ++i) {
622 /* empty the touched set: already done, just clear the list */
625 list_for_each_entry(node_t, x, &X->entries, node_list) {
631 num_edges = get_irn_n_outs(x->node);
633 while (x->next_edge <= num_edges) {
634 ir_def_use_edge *edge = &x->node->out[x->next_edge];
636 /* check if we have necessary edges */
644 /* ignore the "control input" for non-pinned nodes
645 if we are running in GCSE mode */
646 if (i < end_idx && get_irn_pinned(succ) != op_pin_state_pinned)
649 y = get_irn_node(succ);
650 if (is_constant_type(y->type)) {
651 code = get_irn_opcode(succ);
652 if (code == iro_Sub || (code == iro_Proj && is_Cmp(get_Proj_pred(succ))))
653 add_node_to_cprop(y, env);
656 /* Partitions of constants should not be split simply because their Nodes have unequal
657 functions or incongruent inputs. */
658 if (y->type.tv == tarval_bottom &&
659 (! is_Phi(x->node) || is_live_input(x->node, i))) {
661 add_to_touched(Y, env);
662 add_to_partition_touched(y);
667 for (Z = env->touched; Z != NULL; Z = Z->touched_next) {
668 /* remove it from the touched set */
671 if (Z->n_nodes != Z->n_touched) {
672 split(Z, Z->touched, env);
674 /* Empty local Z.touched. */
675 for (e = Z->touched; e != NULL; e = e->next) {
685 * Implements split_by_what(): Split a partition by characteristics given
686 * by the what function.
688 * @param X the partition to split
689 * @param What a function returning an Id for every node of the partition X
690 * @param P an flexible array to store the result partitions or NULL
691 * @param env the environment
693 * @return if P != NULL P will be filled with the resulting partitions and returned
695 static partition_t **split_by_what(partition_t *X, what_func What,
696 partition_t **P, environment_t *env) {
699 listmap_entry_t *iter;
702 /* Let map be an empty mapping from the range of What to (local) list of Nodes. */
704 list_for_each_entry(node_t, x, &X->entries, node_list) {
705 void *id = What(x, env);
706 listmap_entry_t *entry;
709 /* input not allowed, ignore */
712 /* Add x to map[What(x)]. */
713 entry = listmap_find(&map, id);
714 x->next = entry->list;
717 /* Let P be a set of Partitions. */
719 /* for all sets S except one in the range of map do */
720 for (iter = map.values; iter != NULL; iter = iter->next) {
721 if (iter->next == NULL) {
722 /* this is the last entry, ignore */
727 /* Add SPLIT( X, S ) to P. */
728 R = split(X, S, env);
730 ARR_APP1(partition_t *, P, R);
735 ARR_APP1(partition_t *, P, X);
740 } /* split_by_what */
742 /** lambda n.(n.type) */
743 static void *lambda_type(const node_t *node, environment_t *env) {
745 return node->type.tv;
748 /** lambda n.(n.opcode) */
749 static void *lambda_opcode(const node_t *node, environment_t *env) {
750 opcode_key_t key, *entry;
751 ir_node *irn = node->node;
753 key.code = get_irn_opcode(irn);
754 key.mode = get_irn_mode(irn);
755 key.proj = is_Proj(irn) ? get_Proj_proj(irn) : 0;
756 entry = set_insert(env->opcode2id_map, &key, sizeof(key), opcode_hash(&key));
758 } /* lambda_opcode */
760 /** lambda n.(n[i].partition) */
761 static void *lambda_partition(const node_t *node, environment_t *env) {
764 int i = env->lambda_input;
766 if (i >= get_irn_arity(node->node)) {
767 /* we are outside the allowed range */
771 /* ignore the "control input" for non-pinned nodes
772 if we are running in GCSE mode */
773 if (i < env->end_idx && get_irn_pinned(node->node) != op_pin_state_pinned)
776 pred = get_irn_n(node->node, i);
777 p = get_irn_node(pred);
780 } /* lambda_partition */
783 * Checks whether a type is a constant.
785 static int is_type_constant(lattice_elem_t type) {
786 if (is_tarval(type.tv))
787 return tarval_is_constant(type.tv);
788 /* else it is a symconst */
793 * Implements split_by().
795 * @param X the partition to split
796 * @param env the environment
798 static void split_by(partition_t *X, environment_t *env) {
799 partition_t **P = NEW_ARR_F(partition_t *, 0);
802 P = split_by_what(X, lambda_type, P, env);
803 for (i = ARR_LEN(P) - 1; i >= 0; --i) {
804 partition_t *Y = P[i];
806 if (Y->n_nodes > 1) {
807 lattice_elem_t type = get_partition_type(Y);
809 /* we do not want split the TOP, unreachable or constant partitions */
810 if (type.tv != tarval_top && type.tv != tarval_unreachable && !is_type_constant(type)) {
811 partition_t **Q = NEW_ARR_F(partition_t *, 0);
813 Q = split_by_what(Y, lambda_opcode, Q, env);
815 for (j = ARR_LEN(Q) - 1; j >= 0; --j) {
816 partition_t *Z = Q[j];
818 for (k = Z->max_arity - 1; k >= -1; --k) {
819 if (Z->n_nodes > 1) {
820 env->lambda_input = k;
821 split_by_what(Z, lambda_partition, NULL, env);
833 * (Re-)compute the type for a given node.
835 * @param node the node
837 static void default_compute(node_t *node) {
839 ir_node *irn = node->node;
840 tarval *top = tarval_top;
842 if (get_irn_mode(node->node) == mode_X)
843 top = tarval_unreachable;
845 if (get_irn_pinned(irn) == op_pin_state_pinned) {
846 node_t *block = get_irn_node(get_nodes_block(irn));
848 if (block->type.tv == tarval_unreachable) {
854 /* if any of the data inputs have type top, the result is type top */
855 for (i = get_irn_arity(irn) - 1; i >= 0; --i) {
856 ir_node *pred = get_irn_n(irn, i);
857 node_t *p = get_irn_node(pred);
859 if (p->type.tv == tarval_top) {
865 if (get_irn_mode(node->node) == mode_X)
866 node->type.tv = tarval_reachable;
868 node->type.tv = computed_value(irn);
869 } /* default_compute */
872 * (Re-)compute the type for a Block node.
874 * @param node the node
876 static void compute_Block(node_t *node) {
878 ir_node *block = node->node;
880 for (i = get_Block_n_cfgpreds(block) - 1; i >= 0; --i) {
881 node_t *pred = get_irn_node(get_Block_cfgpred(block, i));
883 if (pred->type.tv == tarval_reachable) {
884 /* A block is reachable, if at least of predecessor is reachable. */
885 node->type.tv = tarval_reachable;
889 node->type.tv = tarval_unreachable;
890 } /* compute_Block */
893 * (Re-)compute the type for a Jmp node.
895 * @param node the node
897 static void compute_Jmp(node_t *node) {
898 node_t *block = get_irn_node(get_nodes_block(node->node));
900 node->type = block->type;
904 * (Re-)compute the type for the End node.
906 * @param node the node
908 static void compute_End(node_t *node) {
909 /* the End node is NOT dead of course */
910 node->type.tv = tarval_reachable;
914 * (Re-)compute the type for a SymConst node.
916 * @param node the node
918 static void compute_SymConst(node_t *node) {
919 ir_node *irn = node->node;
920 node_t *block = get_irn_node(get_nodes_block(irn));
922 if (block->type.tv == tarval_unreachable) {
923 node->type.tv = tarval_top;
926 switch (get_SymConst_kind(irn)) {
927 case symconst_addr_ent:
928 /* case symconst_addr_name: cannot handle this yet */
929 node->type.sym = get_SymConst_symbol(irn);
932 node->type.tv = computed_value(irn);
934 } /* compute_SymConst */
937 * (Re-)compute the type for a Phi node.
939 * @param node the node
941 static void compute_Phi(node_t *node) {
943 ir_node *phi = node->node;
946 /* if a Phi is in a unreachable block, its type is TOP */
947 node_t *block = get_irn_node(get_nodes_block(phi));
949 if (block->type.tv == tarval_unreachable) {
950 node->type.tv = tarval_top;
954 /* Phi implements the Meet operation */
955 type.tv = tarval_top;
956 for (i = get_Phi_n_preds(phi) - 1; i >= 0; --i) {
957 node_t *pred = get_irn_node(get_Phi_pred(phi, i));
958 node_t *pred_X = get_irn_node(get_Block_cfgpred(block->node, i));
960 if (pred_X->type.tv == tarval_unreachable || pred->type.tv == tarval_top) {
961 /* ignore TOP inputs: We must check here for unreachable blocks,
962 because Firm constants live in the Start Block are NEVER Top.
963 Else, a Phi (1,2) will produce Bottom, even if the 2 for instance
964 comes from a unreachable input. */
967 if (pred->type.tv == tarval_bottom) {
968 node->type.tv = tarval_bottom;
970 } else if (type.tv == tarval_top) {
971 /* first constant found */
973 } else if (type.tv != pred->type.tv) {
974 /* different constants or tarval_bottom */
975 node->type.tv = tarval_bottom;
978 /* else nothing, constants are the same */
984 * (Re-)compute the type for an Add. Special case: one nodes is a Zero Const.
986 * @param node the node
988 static void compute_Add(node_t *node) {
989 ir_node *sub = node->node;
990 node_t *l = get_irn_node(get_Add_left(sub));
991 node_t *r = get_irn_node(get_Add_right(sub));
992 lattice_elem_t a = l->type;
993 lattice_elem_t b = r->type;
994 node_t *block = get_irn_node(get_nodes_block(sub));
997 if (block->type.tv == tarval_unreachable) {
998 node->type.tv = tarval_top;
1002 if (a.tv == tarval_top || b.tv == tarval_top) {
1003 node->type.tv = tarval_top;
1004 } else if (a.tv == tarval_bottom || b.tv == tarval_bottom) {
1005 node->type.tv = tarval_bottom;
1007 /* x + 0 = 0 + x = x, but beware of floating point +0 + -0, so we
1008 must call tarval_add() first to handle this case! */
1009 if (is_tarval(a.tv)) {
1010 if (is_tarval(b.tv)) {
1011 node->type.tv = tarval_add(a.tv, b.tv);
1014 mode = get_tarval_mode(a.tv);
1015 if (a.tv == get_mode_null(mode)) {
1019 } else if (is_tarval(b.tv)) {
1020 mode = get_tarval_mode(b.tv);
1021 if (b.tv == get_mode_null(mode)) {
1026 node->type.tv = tarval_bottom;
1031 * (Re-)compute the type for a Sub. Special case: both nodes are congruent.
1033 * @param node the node
1035 static void compute_Sub(node_t *node) {
1036 ir_node *sub = node->node;
1037 node_t *l = get_irn_node(get_Sub_left(sub));
1038 node_t *r = get_irn_node(get_Sub_right(sub));
1039 lattice_elem_t a = l->type;
1040 lattice_elem_t b = r->type;
1041 node_t *block = get_irn_node(get_nodes_block(sub));
1043 if (block->type.tv == tarval_unreachable) {
1044 node->type.tv = tarval_top;
1048 if (a.tv == tarval_top || b.tv == tarval_top) {
1049 node->type.tv = tarval_top;
1050 } else if (r->part == l->part) {
1051 ir_mode *mode = get_irn_mode(sub);
1052 node->type.tv = get_mode_null(mode);
1053 } else if (a.tv == tarval_bottom || b.tv == tarval_bottom) {
1054 node->type.tv = tarval_bottom;
1056 if (is_tarval(a.tv) && is_tarval(b.tv))
1057 node->type.tv = tarval_sub(a.tv, b.tv);
1059 node->type.tv = tarval_bottom;
1064 * (Re-)compute the type for a Proj(Cmp).
1066 * @param node the node
1067 * @param cond the predecessor Cmp node
1069 static void compute_Proj_Cmp(node_t *node, ir_node *cmp) {
1070 ir_node *proj = node->node;
1071 node_t *l = get_irn_node(get_Cmp_left(cmp));
1072 node_t *r = get_irn_node(get_Cmp_right(cmp));
1073 lattice_elem_t a = l->type;
1074 lattice_elem_t b = r->type;
1075 pn_Cmp pnc = get_Proj_proj(proj);
1078 * BEWARE: a == a is NOT always True for floating Point values, as
1079 * NaN != NaN is defined, so we must check this here.
1081 if (!mode_is_float(get_irn_mode(l->node)) || pnc == pn_Cmp_Lt || pnc == pn_Cmp_Gt) {
1082 if (a.tv == tarval_top || b.tv == tarval_top) {
1083 node->type.tv = tarval_top;
1084 } else if (r->part == l->part) {
1085 node->type.tv = new_tarval_from_long(pnc & pn_Cmp_Eq, mode_b);
1086 } else if (a.tv == tarval_bottom || b.tv == tarval_bottom) {
1087 node->type.tv = tarval_bottom;
1089 default_compute(node);
1092 default_compute(node);
1094 } /* compute_Proj_Cmp */
1097 * (Re-)compute the type for a Proj(Cond).
1099 * @param node the node
1100 * @param cond the predecessor Cond node
1102 static void compute_Proj_Cond(node_t *node, ir_node *cond) {
1103 ir_node *proj = node->node;
1104 long pnc = get_Proj_proj(proj);
1105 ir_node *sel = get_Cond_selector(cond);
1106 node_t *selector = get_irn_node(sel);
1108 if (get_irn_mode(sel) == mode_b) {
1110 if (pnc == pn_Cond_true) {
1111 if (selector->type.tv == tarval_b_false) {
1112 node->type.tv = tarval_unreachable;
1113 } else if (selector->type.tv == tarval_b_true) {
1114 node->type.tv = tarval_reachable;
1115 } else if (selector->type.tv == tarval_bottom) {
1116 node->type.tv = tarval_reachable;
1118 assert(selector->type.tv == tarval_top);
1119 node->type.tv = tarval_unreachable;
1122 assert(pnc == pn_Cond_false);
1124 if (selector->type.tv == tarval_b_false) {
1125 node->type.tv = tarval_reachable;
1126 } else if (selector->type.tv == tarval_b_true) {
1127 node->type.tv = tarval_unreachable;
1128 } else if (selector->type.tv == tarval_bottom) {
1129 node->type.tv = tarval_reachable;
1131 assert(selector->type.tv == tarval_top);
1132 node->type.tv = tarval_unreachable;
1137 if (selector->type.tv == tarval_bottom) {
1138 node->type.tv = tarval_reachable;
1139 } else if (selector->type.tv == tarval_top) {
1140 node->type.tv = tarval_unreachable;
1142 long value = get_tarval_long(selector->type.tv);
1143 if (pnc == get_Cond_defaultProj(cond)) {
1144 /* default switch, have to check ALL other cases */
1147 for (i = get_irn_n_outs(cond) - 1; i >= 0; --i) {
1148 ir_node *succ = get_irn_out(cond, i);
1152 if (value == get_Proj_proj(succ)) {
1153 /* we found a match, will NOT take the default case */
1154 node->type.tv = tarval_unreachable;
1158 /* all cases checked, no match, will take default case */
1159 node->type.tv = tarval_reachable;
1162 node->type.tv = value == pnc ? tarval_reachable : tarval_unreachable;
1166 } /* compute_Proj_Cond */
1169 * (Re-)compute the type for a Proj-Nodes.
1171 * @param node the node
1173 static void compute_Proj(node_t *node) {
1174 ir_node *proj = node->node;
1175 ir_mode *mode = get_irn_mode(proj);
1178 if (mode == mode_M) {
1179 /* mode M is always bottom */
1180 node->type.tv = tarval_bottom;
1183 if (mode != mode_X) {
1184 ir_node *cmp = get_Proj_pred(proj);
1186 compute_Proj_Cmp(node, cmp);
1188 default_compute(node);
1191 /* handle mode_X nodes */
1192 pred = get_Proj_pred(proj);
1194 switch (get_irn_opcode(pred)) {
1196 /* the Proj_X from the Start is always reachable */
1197 node->type.tv = tarval_reachable;
1200 compute_Proj_Cond(node, pred);
1203 default_compute(node);
1205 } /* compute_Proj */
1208 * (Re-)compute the type for a given node.
1210 * @param node the node
1212 static void compute(node_t *node) {
1213 compute_func func = (compute_func)node->node->op->ops.generic;
1220 * Propagate constant evaluation.
1222 * @param env the environment
1224 static void propagate(environment_t *env) {
1227 lattice_elem_t old_type;
1232 while (env->cprop != NULL) {
1233 /* remove the first partition X from cprop */
1236 env->cprop = X->cprop_next;
1240 while (X->cprop != NULL) {
1241 /* remove the first Node x from X.cprop */
1244 X->cprop = x->cprop_next;
1246 /* compute a new type for x */
1248 DB((dbg, LEVEL_3, "computing type of %+F\n", x->node));
1250 if (x->type.tv != old_type.tv) {
1251 DB((dbg, LEVEL_2, "node %+F has changed type from %+F to %+F\n", x->node, old_type, x->type));
1253 if (x->on_fallen == 0) {
1254 /* Add x to fallen. Nodes might fall from T -> const -> _|_, so check that they are
1255 not already on the list. */
1261 for (i = get_irn_n_outs(x->node) - 1; i >= 0; --i) {
1262 ir_node *succ = get_irn_out(x->node, i);
1263 node_t *y = get_irn_node(succ);
1265 /* Add y to y.partition.cprop. */
1266 add_node_to_cprop(y, env);
1271 if (n_fallen > 0 && n_fallen != X->n_nodes) {
1272 Y = split(X, fallen, env);
1276 /* remove the nodes from the fallen list */
1277 for (x = fallen; x != NULL; x = x->next)
1286 * Get the leader for a given node from its congruence class.
1288 * @param irn the node
1290 static ir_node *get_leader(node_t *node) {
1291 partition_t *part = node->part;
1293 if (part->n_nodes > 1) {
1294 DB((dbg, LEVEL_2, "Found congruence class for %+F\n", node->node));
1296 return get_first_node(part)->node;
1302 * Post-Walker, apply the analysis results;
1304 static void apply_result(ir_node *irn, void *ctx) {
1305 environment_t *env = ctx;
1306 node_t *node = get_irn_node(irn);
1308 if (is_Block(irn)) {
1309 if (irn == get_irg_end_block(current_ir_graph)) {
1310 /* the EndBlock is always reachable even if the analysis
1311 finds out the opposite :-) */
1315 if (node->type.tv == tarval_unreachable) {
1316 /* mark dead blocks */
1317 set_Block_dead(irn);
1319 } else if (is_End(irn)) {
1320 /* do not touch the End node */
1322 node_t *block = get_irn_node(get_nodes_block(irn));
1324 if (block->type.tv == tarval_unreachable) {
1325 ir_node *bad = get_irg_bad(current_ir_graph);
1327 /* here, bad might already have a node, but this can be safely ignored
1328 as long as bad has at least ONE valid node */
1329 set_irn_node(bad, node);
1331 DB((dbg, LEVEL_1, "%+F is unreachable\n", irn));
1334 else if (get_irn_mode(irn) == mode_X) {
1335 if (node->type.tv == tarval_unreachable) {
1336 ir_node *bad = get_irg_bad(current_ir_graph);
1338 /* see comment above */
1339 set_irn_node(bad, node);
1341 DB((dbg, LEVEL_1, "%+F is unreachable\n", irn));
1342 exchange(irn, get_irg_bad(current_ir_graph));
1344 else if (is_Proj(irn)) {
1346 ir_node *cond = get_Proj_pred(irn);
1348 if (is_Cond(cond)) {
1349 node_t *sel = get_irn_node(get_Cond_selector(cond));
1351 if (is_tarval(sel->type.tv) && tarval_is_constant(sel->type.tv)) {
1352 /* Cond selector is a constant, make a Jmp */
1353 ir_node *jmp = new_r_Jmp(current_ir_graph, block->node);
1354 set_irn_node(jmp, node);
1356 DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", irn, jmp));
1362 /* normal data node */
1363 if (is_tarval(node->type.tv) && tarval_is_constant(node->type.tv)) {
1364 tarval *tv = node->type.tv;
1366 if (! is_Const(irn)) {
1367 /* can be replaced by a constant */
1368 ir_node *c = new_r_Const(current_ir_graph, block->node, get_tarval_mode(tv), tv);
1369 set_irn_node(c, node);
1371 DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", irn, c));
1374 } else if (is_entity(node->type.sym.entity_p)) {
1375 if (! is_SymConst(irn)) {
1376 /* can be replaced by a Symconst */
1377 ir_node *symc = new_r_SymConst(current_ir_graph, block->node, get_irn_mode(irn), node->type.sym, symconst_addr_ent);
1378 set_irn_node(symc, node);
1381 DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", irn, symc));
1382 exchange(irn, symc);
1385 ir_node *leader = get_leader(node);
1387 if (leader != irn) {
1388 DB((dbg, LEVEL_1, "%+F is replaced by %+F\n", irn, leader));
1389 exchange(irn, leader);
1394 } /* static void apply_result(ir_node *irn, void *ctx) {
1397 #define SET(code) op_##code->ops.generic = (op_func)compute_##code
1400 * sets the generic functions to compute.
1402 static void set_compute_functions(void) {
1405 /* set the default compute function */
1406 for (i = get_irp_n_opcodes() - 1; i >= 0; --i) {
1407 ir_op *op = get_irp_opcode(i);
1408 op->ops.generic = (op_func)default_compute;
1411 /* set specific functions */
1420 } /* set_compute_functions */
1422 static int dump_partition_hook(FILE *F, ir_node *n, ir_node *local) {
1423 ir_node *irn = local != NULL ? local : n;
1424 node_t *node = get_irn_node(n);
1426 ir_fprintf(F, "info2 : \"partition %u type %+F\"\n", node->part->nr, node->type);
1430 void combo(ir_graph *irg) {
1434 ir_graph *rem = current_ir_graph;
1436 current_ir_graph = irg;
1438 /* register a debug mask */
1439 FIRM_DBG_REGISTER(dbg, "firm.opt.combo");
1440 firm_dbg_set_mask(dbg, SET_LEVEL_1);
1442 DB((dbg, LEVEL_1, "Doing COMBO for %+F\n", irg));
1444 obstack_init(&env.obst);
1445 env.worklist = NULL;
1449 #ifdef DEBUG_libfirm
1450 env.dbg_list = NULL;
1452 env.opcode2id_map = new_set(cmp_opcode, iro_Last * 4);
1453 env.type2id_map = pmap_create();
1454 env.end_idx = get_opt_global_cse() ? 0 : -1;
1455 env.lambda_input = 0;
1457 assure_irg_outs(irg);
1459 /* we have our own value_of function */
1460 set_value_of_func(get_node_tarval);
1462 set_compute_functions();
1464 /* create the initial partition and place it on the work list */
1465 env.initial = new_partition(&env);
1466 add_to_worklist(env.initial, &env);
1467 irg_walk_graph(irg, NULL, create_initial_partitions, &env);
1469 /* Place the START Node's partition on cprop.
1470 Place the START Node on its local worklist. */
1471 initial_X = get_irg_initial_exec(irg);
1472 start = get_irn_node(initial_X);
1473 add_node_to_cprop(start, &env);
1477 if (env.worklist != NULL)
1479 } while (env.cprop != NULL || env.worklist != NULL);
1481 dump_all_partitions(&env);
1483 set_dump_node_vcgattr_hook(dump_partition_hook);
1484 dump_ir_block_graph(irg, "-partition");
1485 set_dump_node_vcgattr_hook(NULL);
1488 /* apply the result */
1489 irg_walk_graph(irg, NULL, apply_result, &env);
1491 pmap_destroy(env.type2id_map);
1492 del_set(env.opcode2id_map);
1493 obstack_free(&env.obst, NULL);
1495 /* restore value_of() default behavior */
1496 set_value_of_func(NULL);
1497 current_ir_graph = rem;