2 * Copyright (C) 1995-2010 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 analyze graph to provide value range information
29 #include "iroptimize.h"
31 #include "irgraph_t.h"
39 #include "irnodemap.h"
44 DEBUG_ONLY(static firm_dbg_module_t *dbg;)
46 typedef struct vrp_env_t {
52 static vrp_attr *vrp_get_or_set_info(ir_vrp_info *info, const ir_node *node)
54 vrp_attr *attr = ir_nodemap_get(vrp_attr, &info->infos, node);
56 ir_mode *mode = get_irn_mode(node);
57 assert(mode_is_int(mode));
59 attr = OALLOCZ(&info->obst, vrp_attr);
60 attr->range_type = VRP_UNDEFINED;
61 attr->bits_set = get_mode_null(mode);
62 attr->bits_not_set = get_mode_all_one(mode);
63 attr->range_bottom = get_tarval_top();
64 attr->range_top = get_tarval_top();
66 ir_nodemap_insert(&info->infos, node, attr);
71 vrp_attr *vrp_get_info(const ir_node *node)
73 ir_graph *irg = get_irn_irg(node);
74 if (irg->vrp.infos.data == NULL)
76 return ir_nodemap_get(vrp_attr, &irg->vrp.infos, node);
79 static int vrp_update_node(ir_vrp_info *info, ir_node *node)
81 ir_tarval *new_bits_set = get_tarval_bad();
82 ir_tarval *new_bits_not_set = get_tarval_bad();
83 ir_tarval *new_range_bottom = get_tarval_bad();
84 ir_tarval *new_range_top = get_tarval_bad();
85 enum range_types new_range_type = VRP_UNDEFINED;
86 int something_changed = 0;
89 if (!mode_is_int(get_irn_mode(node))) {
90 return 0; /* we don't optimize for non-int-nodes*/
93 vrp = vrp_get_or_set_info(info, node);
95 /* TODO: Check if all predecessors have valid VRP information*/
97 switch (get_irn_opcode(node)) {
99 ir_tarval *tv = get_Const_tarval(node);
101 new_bits_not_set = tv;
102 new_range_bottom = tv;
104 new_range_type = VRP_RANGE;
108 const vrp_attr *vrp_left, *vrp_right;
109 const ir_node *left, *right;
111 left = get_And_left(node);
112 right = get_And_right(node);
113 vrp_left = vrp_get_or_set_info(info, left);
114 vrp_right = vrp_get_or_set_info(info, right);
115 new_bits_set = tarval_and(vrp_left->bits_set, vrp_right->bits_set);
116 new_bits_not_set = tarval_and(vrp_left->bits_not_set, vrp_right->bits_not_set);
122 int overflow_top, overflow_bottom;
123 ir_tarval *new_top, *new_bottom;
124 const vrp_attr *vrp_left, *vrp_right;
125 vrp_left = vrp_get_or_set_info(info, get_Add_left(node));
126 vrp_right = vrp_get_or_set_info(info, get_Add_right(node));
128 if (vrp_left->range_type == VRP_UNDEFINED || vrp_right->range_type ==
129 VRP_UNDEFINED || vrp_left->range_type == VRP_VARYING ||
130 vrp_right->range_type == VRP_VARYING) {
134 new_top = tarval_add(vrp_left->range_top, vrp_right->range_top);
135 overflow_top = tarval_carry();
136 new_bottom = tarval_add(vrp_left->range_bottom, vrp_right->range_bottom);
137 overflow_bottom = tarval_carry();
139 if (!overflow_top && !overflow_bottom && vrp_left->range_type == VRP_RANGE
140 &&vrp_right->range_type == VRP_RANGE) {
141 new_range_bottom = new_bottom;
142 new_range_top = new_top;
143 new_range_type = VRP_RANGE;
146 if (overflow_top || overflow_bottom) {
147 /* TODO Implement overflow handling*/
148 new_range_type = VRP_UNDEFINED;
154 ir_node *left = get_Sub_left(node);
155 ir_node *right = get_Sub_right(node);
156 int overflow_top, overflow_bottom;
157 ir_tarval *new_top, *new_bottom;
158 const vrp_attr *vrp_left, *vrp_right;
160 if (!mode_is_int(get_irn_mode(left)))
163 vrp_left = vrp_get_or_set_info(info, left);
164 vrp_right = vrp_get_or_set_info(info, right);
166 if (vrp_left->range_type == VRP_UNDEFINED || vrp_right->range_type ==
167 VRP_UNDEFINED || vrp_left->range_type == VRP_VARYING ||
168 vrp_right->range_type == VRP_VARYING) {
172 new_top = tarval_sub(vrp_left->range_top, vrp_right->range_top, NULL);
173 overflow_top = tarval_carry();
174 new_bottom = tarval_sub(vrp_left->range_bottom, vrp_right->range_bottom, NULL);
175 overflow_bottom = tarval_carry();
177 if (!overflow_top && !overflow_bottom && vrp_left->range_type == VRP_RANGE
178 &&vrp_right->range_type == VRP_RANGE) {
179 new_range_bottom = new_bottom;
180 new_range_top = new_top;
181 new_range_type = VRP_RANGE;
184 if (overflow_top || overflow_bottom) {
185 /* TODO Implement overflow handling*/
191 const vrp_attr *vrp_left, *vrp_right;
193 vrp_left = vrp_get_or_set_info(info, get_Or_left(node));
194 vrp_right = vrp_get_or_set_info(info, get_Or_right(node));
196 new_bits_set = tarval_or(vrp_left->bits_set, vrp_right->bits_set);
197 new_bits_not_set = tarval_or(vrp_left->bits_not_set, vrp_right->bits_not_set);
203 const vrp_attr *vrp_left;
204 const ir_node *right = get_Rotl_right(node);
206 vrp_left = vrp_get_or_set_info(info, get_Rotl_left(node));
208 /* We can only compute this if the right value is a constant*/
209 if (is_Const(right)) {
210 new_bits_set = tarval_rotl(vrp_left->bits_set, get_Const_tarval(right));
211 new_bits_not_set = tarval_rotl(vrp_left->bits_not_set, get_Const_tarval(right));
217 const vrp_attr *vrp_left;
218 const ir_node *right = get_Shl_right(node);
219 vrp_left = vrp_get_or_set_info(info, get_Shl_left(node));
221 /* We can only compute this if the right value is a constant*/
222 if (is_Const(right)) {
223 new_bits_set = tarval_shl(vrp_left->bits_set, get_Const_tarval(right));
224 new_bits_not_set = tarval_shl(vrp_left->bits_not_set, get_Const_tarval(right));
230 const vrp_attr *vrp_left;
231 const ir_node *right = get_Shr_right(node);
233 vrp_left = vrp_get_or_set_info(info, get_Shr_left(node));
235 /* We can only compute this if the right value is a constant*/
236 if (is_Const(right)) {
237 new_bits_set = tarval_shr(vrp_left->bits_set, get_Const_tarval(right));
238 new_bits_not_set = tarval_shr(vrp_left->bits_not_set, get_Const_tarval(right));
244 const vrp_attr *vrp_left;
245 const ir_node *right = get_Shrs_right(node);
247 vrp_left = vrp_get_or_set_info(info, get_Shrs_left(node));
249 /* We can only compute this if the right value is a constant*/
250 if (is_Const(right)) {
251 new_bits_set = tarval_shrs(vrp_left->bits_set, get_Const_tarval(right));
252 new_bits_not_set = tarval_shrs(vrp_left->bits_not_set, get_Const_tarval(right));
258 const vrp_attr *vrp_left, *vrp_right;
260 vrp_left = vrp_get_or_set_info(info, get_Eor_left(node));
261 vrp_right = vrp_get_or_set_info(info, get_Eor_right(node));
263 new_bits_set = tarval_or(
264 tarval_and(vrp_left->bits_set, tarval_not(vrp_right->bits_not_set)),
265 tarval_and(tarval_not(vrp_left->bits_not_set), vrp_right->bits_set));
267 new_bits_not_set = tarval_not(tarval_or(
268 tarval_and(vrp_left->bits_set,vrp_right->bits_set),
269 tarval_and(tarval_not(vrp_left->bits_not_set),
270 tarval_not(vrp_right->bits_not_set))));
276 const vrp_attr *vrp_pred = vrp_get_or_set_info(info, get_Id_pred(node));
277 new_bits_set = vrp_pred->bits_set;
278 new_bits_not_set = vrp_pred->bits_not_set;
279 new_range_top = vrp_pred->range_top;
280 new_range_bottom = vrp_pred->range_bottom;
281 new_range_type = vrp_pred->range_type;
286 const vrp_attr *vrp_pred = vrp_get_or_set_info(info, get_Not_op(node));
287 new_bits_set = tarval_not(vrp_pred->bits_not_set);
288 new_bits_not_set = tarval_not(vrp_pred->bits_set);
293 const ir_node *pred = get_Conv_op(node);
294 ir_mode *old_mode = get_irn_mode(pred);
295 const vrp_attr *vrp_pred;
299 if (!mode_is_int(old_mode))
302 vrp_pred = vrp_get_or_set_info(info, pred);
303 new_mode = get_irn_mode(node);
305 /* The second and is needed if target type is smaller*/
306 new_bits_not_set = tarval_convert_to(get_mode_all_one(old_mode), new_mode);
307 new_bits_not_set = tarval_and(new_bits_not_set, tarval_convert_to(vrp_pred->bits_not_set, new_mode));
308 new_bits_set = tarval_and(
309 new_bits_not_set, tarval_convert_to(vrp_pred->bits_set, new_mode));
311 /* Matze: TODO, BUGGY, tarval_cmp never returns ir_relation_less_equal */
312 if (tarval_cmp(vrp_pred->range_top, get_mode_max(new_mode)) == ir_relation_less_equal) {
313 vrp->range_top = vrp_pred->range_top;
316 /* Matze: TODO, BUGGY, tarval_cmp never returns ir_relation_greater_equal */
317 if (tarval_cmp(vrp_pred->range_bottom, get_mode_min(new_mode)) == ir_relation_greater_equal) {
318 vrp->range_bottom = vrp_pred->range_bottom;
324 const ir_relation relation = get_Confirm_relation(node);
325 const ir_node *bound = get_Confirm_bound(node);
328 if (relation == ir_relation_less_greater) {
329 /** @todo: Handle non-Const bounds */
330 if (is_Const(bound)) {
331 new_range_type = VRP_ANTIRANGE;
332 new_range_top = get_Const_tarval(bound);
333 new_range_bottom = get_Const_tarval(bound);
335 } else if (relation == ir_relation_less_equal) {
336 if (is_Const(bound)) {
337 new_range_type = VRP_RANGE;
338 new_range_top = get_Const_tarval(bound);
339 new_range_bottom = get_tarval_min(get_irn_mode(node));
346 /* combine all ranges*/
348 int num = get_Phi_n_preds(node);
349 ir_relation relation;
352 const ir_node *pred = get_Phi_pred(node,0);
353 const vrp_attr *vrp_pred = vrp_get_or_set_info(info, pred);
354 new_range_top = vrp_pred->range_top;
355 new_range_bottom = vrp_pred->range_bottom;
356 new_range_type = vrp_pred->range_type;
357 new_bits_set = vrp_pred->bits_set;
358 new_bits_not_set = vrp_pred->bits_not_set;
362 for (i = 1; i < num; i++) {
363 pred = get_Phi_pred(node, i);
364 vrp_pred = vrp_get_or_set_info(info, pred);
365 if (new_range_type == VRP_RANGE && vrp_pred->range_type ==
367 relation = tarval_cmp(new_range_top, vrp_pred->range_top);
368 if (relation == ir_relation_less) {
369 new_range_top = vrp_pred->range_top;
371 relation = tarval_cmp(new_range_bottom, vrp_pred->range_bottom);
372 if (relation == ir_relation_greater) {
373 new_range_bottom = vrp_pred->range_bottom;
376 new_range_type = VRP_VARYING;
378 new_bits_set = tarval_and(new_bits_set, vrp_pred->bits_set);
379 new_bits_not_set = tarval_or(new_bits_not_set,
380 vrp_pred->bits_not_set);
386 /* unhandled, therefore never updated */
392 /* TODO: Check, if there can be information derived from any of these:
393 is_Abs(node) is_Alloc(node) is_Anchor(node) is_Borrow(node) is_Bound(node)
394 is_Break(node) is_Builtin(node) is_Call(node)
395 is_Carry(node) is_Cast(node) is_Cmp(node) is_Cond(node)
396 is_CopyB(node) is_Div(node) is_Dummy(node)
397 is_End(node) is_Free(node)
398 is_IJmp(node) is_InstOf(node) is_Jmp(node) is_Load(node) is_Minus(node)
399 is_Mod(node) is_Mul(node) is_Mulh(node) is_Mux(node) is_NoMem(node)
400 is_Pin(node) is_Proj(node)
401 is_Raise(node) is_Return(node) is_Sel(node) is_Start(node) is_Store(node)
402 is_SymConst(node) is_Sync(node) is_Tuple(node)
405 /* @todo: At this place, we check if the mode of the variable changed. A
406 * better place for this might be in the convopt.c file
409 if (new_bits_set != tarval_bad && get_tarval_mode(new_bits_set) != get_tarval_mode(vrp->bits_set)) {
410 vrp->bits_set = tarval_convert_to(vrp->bits_set, get_irn_mode(node));
412 if (new_bits_not_set != tarval_bad && get_tarval_mode(new_bits_not_set) != get_tarval_mode(vrp->bits_not_set)) {
413 vrp->bits_not_set = tarval_convert_to(vrp->bits_not_set, get_irn_mode(node));
416 if (vrp->range_type != VRP_UNDEFINED && new_range_type != VRP_UNDEFINED && get_tarval_mode(new_range_top) != get_tarval_mode(vrp->range_top)) {
417 /* @todo: We might be able to preserve this range information if it
419 vrp->range_type = VRP_VARYING;
422 /* Merge the newly calculated values with those that might already exist*/
423 if (new_bits_set != tarval_bad) {
424 new_bits_set = tarval_or(new_bits_set, vrp->bits_set);
425 if (new_bits_set != vrp->bits_set) {
426 something_changed = 1;
427 vrp->bits_set = new_bits_set;
430 if (new_bits_not_set != tarval_bad) {
431 new_bits_not_set = tarval_and(new_bits_not_set, vrp->bits_not_set);
433 if (new_bits_not_set != vrp->bits_not_set) {
434 something_changed = 1;
435 vrp->bits_not_set = new_bits_not_set;
439 if (vrp->range_type == VRP_UNDEFINED &&
440 new_range_type != VRP_UNDEFINED) {
441 something_changed = 1;
442 vrp->range_type = new_range_type;
443 vrp->range_bottom = new_range_bottom;
444 vrp->range_top = new_range_top;
446 } else if (vrp->range_type == VRP_RANGE) {
447 if (new_range_type == VRP_RANGE) {
448 if (tarval_cmp(vrp->range_bottom, new_range_bottom) == ir_relation_less) {
449 something_changed = 1;
450 vrp->range_bottom = new_range_bottom;
452 if (tarval_cmp(vrp->range_top, new_range_top) == ir_relation_greater) {
453 something_changed = 1;
454 vrp->range_top = new_range_top;
458 if (new_range_type == VRP_ANTIRANGE) {
459 /* if they are overlapping, cut the range.*/
460 /* TODO: Maybe we can preserve more information here*/
461 if (tarval_cmp(vrp->range_bottom, new_range_top) == ir_relation_greater &&
462 tarval_cmp(vrp->range_bottom, new_range_bottom) == ir_relation_greater) {
463 something_changed = 1;
464 vrp->range_bottom = new_range_top;
466 } else if (tarval_cmp(vrp->range_top, new_range_bottom) == ir_relation_greater &&
467 tarval_cmp(vrp->range_top, new_range_top) == ir_relation_less) {
468 something_changed = 1;
469 vrp->range_top = new_range_bottom;
472 /* We can not handle the case where the anti range is in the*/
476 } else if (vrp->range_type == VRP_ANTIRANGE) {
477 if (new_range_type == VRP_ANTIRANGE) {
478 if (tarval_cmp(vrp->range_bottom, new_range_bottom) == ir_relation_greater) {
479 something_changed = 1;
480 vrp->range_bottom = new_range_bottom;
482 if (tarval_cmp(vrp->range_top, new_range_top) == ir_relation_less) {
483 something_changed = 1;
484 vrp->range_top = new_range_top;
488 if (new_range_type == VRP_RANGE) {
489 if (tarval_cmp(vrp->range_bottom, new_range_top) == ir_relation_greater) {
490 something_changed = 1;
491 vrp->range_bottom = new_range_top;
493 if (tarval_cmp(vrp->range_top, new_range_bottom) == ir_relation_less) {
494 something_changed = 1;
495 vrp->range_top = new_range_bottom;
500 assert(tarval_is_null(
501 tarval_and(vrp->bits_set, tarval_not(vrp->bits_not_set))));
502 return something_changed;
505 static void vrp_first_pass(ir_node *n, void *e)
508 vrp_env_t *env = (vrp_env_t*) e;
513 bitset_set(env->visited, get_irn_idx(n));
515 vrp_update_node(env->info, n);
517 assure_irg_outs(get_irn_irg(n));
518 for (i = get_irn_n_outs(n) - 1; i >=0; --i) {
519 ir_node *succ = get_irn_out(n, i);
520 if (bitset_is_set(env->visited, get_irn_idx(succ))) {
522 waitq_put(env->workqueue, succ);
527 static void dump_vrp_info(void *ctx, FILE *F, const ir_node *node)
532 if (!mode_is_int(get_irn_mode(node)))
535 vrp = vrp_get_info(node);
539 fprintf(F, "vrp range type: %d\n", (int) vrp->range_type);
540 if (vrp->range_type == VRP_RANGE || vrp->range_type == VRP_ANTIRANGE) {
541 ir_fprintf(F, "vrp range bottom: %T\n",vrp->range_bottom);
542 ir_fprintf(F, "vrp range top: %T\n", vrp->range_top);
544 ir_fprintf(F, "vrp bits set: %T\n", vrp->bits_set);
545 ir_fprintf(F, "vrp bits not set: %T\n", vrp->bits_not_set);
548 static hook_entry_t dump_hook;
550 void set_vrp_data(ir_graph *irg)
552 ir_node *succ, *node;
557 if (irg->vrp.infos.data != NULL)
560 FIRM_DBG_REGISTER(dbg, "ir.ana.vrp");
562 assure_irg_outs(irg); /* ensure that out edges are consistent*/
563 ir_nodemap_init(&irg->vrp.infos, irg);
564 obstack_init(&irg->vrp.obst);
567 if (dump_hook.hook._hook_node_info == NULL) {
568 dump_hook.hook._hook_node_info = dump_vrp_info;
569 register_hook(hook_node_info, &dump_hook);
572 env = OALLOCZ(&irg->vrp.obst, vrp_env_t);
573 env->workqueue = new_waitq();
576 env->visited = bitset_malloc(get_irg_last_idx(irg));
577 irg_walk_graph(irg, NULL, vrp_first_pass, env);
578 bitset_free(env->visited);
580 /* while there are entries in the worklist, continue*/
581 while (!waitq_empty(env->workqueue)) {
582 node = (ir_node*) waitq_get(env->workqueue);
584 if (vrp_update_node(info, node)) {
585 /* if something changed, add successors to worklist*/
586 for (i = get_irn_n_outs(node) - 1; i >= 0; --i) {
587 succ = get_irn_out(node, i);
588 waitq_put(env->workqueue, succ);
592 del_waitq(env->workqueue);
595 void free_vrp_data(ir_graph *irg)
597 if (irg->vrp.infos.data == NULL)
599 obstack_free(&irg->vrp.obst, NULL);
600 ir_nodemap_destroy(&irg->vrp.infos);
603 ir_graph_pass_t *set_vrp_pass(const char *name)
605 return def_graph_pass(name ? name : "set_vrp", set_vrp_data);
608 ir_relation vrp_cmp(const ir_node *left, const ir_node *right)
610 vrp_attr *vrp_left, *vrp_right;
612 if (!mode_is_int(get_irn_mode(left)))
613 return ir_relation_true;
615 vrp_left = vrp_get_info(left);
616 vrp_right = vrp_get_info(right);
618 if (!vrp_left || !vrp_right)
619 return ir_relation_true;
621 if (vrp_left->range_type == VRP_RANGE && vrp_right->range_type == VRP_RANGE) {
622 if (tarval_cmp(vrp_left->range_top, vrp_right->range_bottom) == ir_relation_less) {
623 return ir_relation_less;
625 if (tarval_cmp(vrp_left->range_bottom, vrp_right->range_top) == ir_relation_greater) {
626 return ir_relation_greater;
630 if (!tarval_is_null(tarval_and(vrp_left->bits_set, tarval_not(vrp_right->bits_not_set))) ||
631 !tarval_is_null(tarval_and(tarval_not(vrp_left->bits_not_set), vrp_right->bits_set))) {
632 return ir_relation_less_greater;
635 /* TODO: We can get way more information here*/
636 return ir_relation_true;