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 const vrp_attr *vrp_left = vrp_get_or_set_info(info, get_Add_left(node));
123 const vrp_attr *vrp_right = vrp_get_or_set_info(info, get_Add_right(node));
125 if (vrp_left->range_type == VRP_UNDEFINED
126 || vrp_right->range_type == VRP_UNDEFINED
127 || vrp_left->range_type == VRP_VARYING
128 || vrp_right->range_type == VRP_VARYING) {
132 if (vrp_left->range_type == VRP_RANGE
133 && vrp_right->range_type == VRP_RANGE) {
134 tarval_int_overflow_mode_t rem = tarval_get_integer_overflow_mode();
135 tarval_set_integer_overflow_mode(TV_OVERFLOW_BAD);
137 = tarval_add(vrp_left->range_top, vrp_right->range_top);
138 ir_tarval *new_bottom
139 = tarval_add(vrp_left->range_bottom, vrp_right->range_bottom);
140 tarval_set_integer_overflow_mode(rem);
142 if (new_top != tarval_bad && new_bottom != tarval_bad) {
143 new_range_bottom = new_bottom;
144 new_range_top = new_top;
145 new_range_type = VRP_RANGE;
147 /* TODO Implement overflow handling*/
148 new_range_type = VRP_UNDEFINED;
155 ir_node *left = get_Sub_left(node);
156 ir_node *right = get_Sub_right(node);
158 if (!mode_is_int(get_irn_mode(left)))
161 const vrp_attr *vrp_left = vrp_get_or_set_info(info, left);
162 const vrp_attr *vrp_right = vrp_get_or_set_info(info, right);
164 if (vrp_left->range_type == VRP_UNDEFINED
165 || vrp_right->range_type == VRP_UNDEFINED
166 || vrp_left->range_type == VRP_VARYING
167 || vrp_right->range_type == VRP_VARYING) {
171 if (vrp_left->range_type == VRP_RANGE
172 && vrp_right->range_type == VRP_RANGE) {
173 tarval_int_overflow_mode_t rem = tarval_get_integer_overflow_mode();
174 tarval_set_integer_overflow_mode(TV_OVERFLOW_BAD);
175 ir_tarval *new_top = tarval_sub(vrp_left->range_top, vrp_right->range_top, NULL);
176 ir_tarval *new_bottom = tarval_sub(vrp_left->range_bottom, vrp_right->range_bottom, NULL);
177 tarval_set_integer_overflow_mode(rem);
179 if (new_top != tarval_bad && new_bottom != tarval_bad) {
180 new_range_bottom = new_bottom;
181 new_range_top = new_top;
182 new_range_type = VRP_RANGE;
184 /* TODO Implement overflow handling*/
185 new_range_type = VRP_UNDEFINED;
192 const vrp_attr *vrp_left, *vrp_right;
194 vrp_left = vrp_get_or_set_info(info, get_Or_left(node));
195 vrp_right = vrp_get_or_set_info(info, get_Or_right(node));
197 new_bits_set = tarval_or(vrp_left->bits_set, vrp_right->bits_set);
198 new_bits_not_set = tarval_or(vrp_left->bits_not_set, vrp_right->bits_not_set);
204 const vrp_attr *vrp_left;
205 const ir_node *right = get_Rotl_right(node);
207 vrp_left = vrp_get_or_set_info(info, get_Rotl_left(node));
209 /* We can only compute this if the right value is a constant*/
210 if (is_Const(right)) {
211 new_bits_set = tarval_rotl(vrp_left->bits_set, get_Const_tarval(right));
212 new_bits_not_set = tarval_rotl(vrp_left->bits_not_set, get_Const_tarval(right));
218 const vrp_attr *vrp_left;
219 const ir_node *right = get_Shl_right(node);
220 vrp_left = vrp_get_or_set_info(info, get_Shl_left(node));
222 /* We can only compute this if the right value is a constant*/
223 if (is_Const(right)) {
224 new_bits_set = tarval_shl(vrp_left->bits_set, get_Const_tarval(right));
225 new_bits_not_set = tarval_shl(vrp_left->bits_not_set, get_Const_tarval(right));
231 const vrp_attr *vrp_left;
232 const ir_node *right = get_Shr_right(node);
234 vrp_left = vrp_get_or_set_info(info, get_Shr_left(node));
236 /* We can only compute this if the right value is a constant*/
237 if (is_Const(right)) {
238 new_bits_set = tarval_shr(vrp_left->bits_set, get_Const_tarval(right));
239 new_bits_not_set = tarval_shr(vrp_left->bits_not_set, get_Const_tarval(right));
245 const vrp_attr *vrp_left;
246 const ir_node *right = get_Shrs_right(node);
248 vrp_left = vrp_get_or_set_info(info, get_Shrs_left(node));
250 /* We can only compute this if the right value is a constant*/
251 if (is_Const(right)) {
252 new_bits_set = tarval_shrs(vrp_left->bits_set, get_Const_tarval(right));
253 new_bits_not_set = tarval_shrs(vrp_left->bits_not_set, get_Const_tarval(right));
259 const vrp_attr *vrp_left, *vrp_right;
261 vrp_left = vrp_get_or_set_info(info, get_Eor_left(node));
262 vrp_right = vrp_get_or_set_info(info, get_Eor_right(node));
264 new_bits_set = tarval_or(
265 tarval_and(vrp_left->bits_set, tarval_not(vrp_right->bits_not_set)),
266 tarval_and(tarval_not(vrp_left->bits_not_set), vrp_right->bits_set));
268 new_bits_not_set = tarval_not(tarval_or(
269 tarval_and(vrp_left->bits_set,vrp_right->bits_set),
270 tarval_and(tarval_not(vrp_left->bits_not_set),
271 tarval_not(vrp_right->bits_not_set))));
277 const vrp_attr *vrp_pred = vrp_get_or_set_info(info, get_Id_pred(node));
278 new_bits_set = vrp_pred->bits_set;
279 new_bits_not_set = vrp_pred->bits_not_set;
280 new_range_top = vrp_pred->range_top;
281 new_range_bottom = vrp_pred->range_bottom;
282 new_range_type = vrp_pred->range_type;
287 const vrp_attr *vrp_pred = vrp_get_or_set_info(info, get_Not_op(node));
288 new_bits_set = tarval_not(vrp_pred->bits_not_set);
289 new_bits_not_set = tarval_not(vrp_pred->bits_set);
294 const ir_node *pred = get_Conv_op(node);
295 ir_mode *old_mode = get_irn_mode(pred);
296 const vrp_attr *vrp_pred;
300 if (!mode_is_int(old_mode))
303 vrp_pred = vrp_get_or_set_info(info, pred);
304 new_mode = get_irn_mode(node);
306 /* The second and is needed if target type is smaller*/
307 new_bits_not_set = tarval_convert_to(get_mode_all_one(old_mode), new_mode);
308 new_bits_not_set = tarval_and(new_bits_not_set, tarval_convert_to(vrp_pred->bits_not_set, new_mode));
309 new_bits_set = tarval_and(
310 new_bits_not_set, tarval_convert_to(vrp_pred->bits_set, new_mode));
312 /* Matze: TODO, BUGGY, tarval_cmp never returns ir_relation_less_equal */
313 if (tarval_cmp(vrp_pred->range_top, get_mode_max(new_mode)) == ir_relation_less_equal) {
314 vrp->range_top = vrp_pred->range_top;
317 /* Matze: TODO, BUGGY, tarval_cmp never returns ir_relation_greater_equal */
318 if (tarval_cmp(vrp_pred->range_bottom, get_mode_min(new_mode)) == ir_relation_greater_equal) {
319 vrp->range_bottom = vrp_pred->range_bottom;
325 const ir_relation relation = get_Confirm_relation(node);
326 const ir_node *bound = get_Confirm_bound(node);
329 if (relation == ir_relation_less_greater) {
330 /** @todo: Handle non-Const bounds */
331 if (is_Const(bound)) {
332 new_range_type = VRP_ANTIRANGE;
333 new_range_top = get_Const_tarval(bound);
334 new_range_bottom = get_Const_tarval(bound);
336 } else if (relation == ir_relation_less_equal) {
337 if (is_Const(bound)) {
338 new_range_type = VRP_RANGE;
339 new_range_top = get_Const_tarval(bound);
340 new_range_bottom = get_tarval_min(get_irn_mode(node));
347 /* combine all ranges*/
349 int num = get_Phi_n_preds(node);
350 ir_relation relation;
353 const ir_node *pred = get_Phi_pred(node,0);
354 const vrp_attr *vrp_pred = vrp_get_or_set_info(info, pred);
355 new_range_top = vrp_pred->range_top;
356 new_range_bottom = vrp_pred->range_bottom;
357 new_range_type = vrp_pred->range_type;
358 new_bits_set = vrp_pred->bits_set;
359 new_bits_not_set = vrp_pred->bits_not_set;
363 for (i = 1; i < num; i++) {
364 pred = get_Phi_pred(node, i);
365 vrp_pred = vrp_get_or_set_info(info, pred);
366 if (new_range_type == VRP_RANGE && vrp_pred->range_type ==
368 relation = tarval_cmp(new_range_top, vrp_pred->range_top);
369 if (relation == ir_relation_less) {
370 new_range_top = vrp_pred->range_top;
372 relation = tarval_cmp(new_range_bottom, vrp_pred->range_bottom);
373 if (relation == ir_relation_greater) {
374 new_range_bottom = vrp_pred->range_bottom;
377 new_range_type = VRP_VARYING;
379 new_bits_set = tarval_and(new_bits_set, vrp_pred->bits_set);
380 new_bits_not_set = tarval_or(new_bits_not_set,
381 vrp_pred->bits_not_set);
387 /* unhandled, therefore never updated */
393 /* TODO: Check, if there can be information derived from any of these:
394 is_Abs(node) is_Alloc(node) is_Anchor(node) is_Borrow(node) is_Bound(node)
395 is_Break(node) is_Builtin(node) is_Call(node)
396 is_Carry(node) is_Cmp(node) is_Cond(node)
397 is_CopyB(node) is_Div(node) is_Dummy(node)
398 is_End(node) is_Free(node)
399 is_IJmp(node) is_InstOf(node) is_Jmp(node) is_Load(node) is_Minus(node)
400 is_Mod(node) is_Mul(node) is_Mulh(node) is_Mux(node) is_NoMem(node)
401 is_Pin(node) is_Proj(node)
402 is_Raise(node) is_Return(node) is_Sel(node) is_Start(node) is_Store(node)
403 is_SymConst(node) is_Sync(node) is_Tuple(node)
406 /* @todo: At this place, we check if the mode of the variable changed. A
407 * better place for this might be in the convopt.c file
410 if (new_bits_set != tarval_bad && get_tarval_mode(new_bits_set) != get_tarval_mode(vrp->bits_set)) {
411 vrp->bits_set = tarval_convert_to(vrp->bits_set, get_irn_mode(node));
413 if (new_bits_not_set != tarval_bad && get_tarval_mode(new_bits_not_set) != get_tarval_mode(vrp->bits_not_set)) {
414 vrp->bits_not_set = tarval_convert_to(vrp->bits_not_set, get_irn_mode(node));
417 if (vrp->range_type != VRP_UNDEFINED && new_range_type != VRP_UNDEFINED && get_tarval_mode(new_range_top) != get_tarval_mode(vrp->range_top)) {
418 /* @todo: We might be able to preserve this range information if it
420 vrp->range_type = VRP_VARYING;
423 /* Merge the newly calculated values with those that might already exist*/
424 if (new_bits_set != tarval_bad) {
425 new_bits_set = tarval_or(new_bits_set, vrp->bits_set);
426 if (new_bits_set != vrp->bits_set) {
427 something_changed = 1;
428 vrp->bits_set = new_bits_set;
431 if (new_bits_not_set != tarval_bad) {
432 new_bits_not_set = tarval_and(new_bits_not_set, vrp->bits_not_set);
434 if (new_bits_not_set != vrp->bits_not_set) {
435 something_changed = 1;
436 vrp->bits_not_set = new_bits_not_set;
440 if (vrp->range_type == VRP_UNDEFINED &&
441 new_range_type != VRP_UNDEFINED) {
442 something_changed = 1;
443 vrp->range_type = new_range_type;
444 vrp->range_bottom = new_range_bottom;
445 vrp->range_top = new_range_top;
447 } else if (vrp->range_type == VRP_RANGE) {
448 if (new_range_type == VRP_RANGE) {
449 if (tarval_cmp(vrp->range_bottom, new_range_bottom) == ir_relation_less) {
450 something_changed = 1;
451 vrp->range_bottom = new_range_bottom;
453 if (tarval_cmp(vrp->range_top, new_range_top) == ir_relation_greater) {
454 something_changed = 1;
455 vrp->range_top = new_range_top;
459 if (new_range_type == VRP_ANTIRANGE) {
460 /* if they are overlapping, cut the range.*/
461 /* TODO: Maybe we can preserve more information here*/
462 if (tarval_cmp(vrp->range_bottom, new_range_top) == ir_relation_greater &&
463 tarval_cmp(vrp->range_bottom, new_range_bottom) == ir_relation_greater) {
464 something_changed = 1;
465 vrp->range_bottom = new_range_top;
467 } else if (tarval_cmp(vrp->range_top, new_range_bottom) == ir_relation_greater &&
468 tarval_cmp(vrp->range_top, new_range_top) == ir_relation_less) {
469 something_changed = 1;
470 vrp->range_top = new_range_bottom;
473 /* We can not handle the case where the anti range is in the*/
477 } else if (vrp->range_type == VRP_ANTIRANGE) {
478 if (new_range_type == VRP_ANTIRANGE) {
479 if (tarval_cmp(vrp->range_bottom, new_range_bottom) == ir_relation_greater) {
480 something_changed = 1;
481 vrp->range_bottom = new_range_bottom;
483 if (tarval_cmp(vrp->range_top, new_range_top) == ir_relation_less) {
484 something_changed = 1;
485 vrp->range_top = new_range_top;
489 if (new_range_type == VRP_RANGE) {
490 if (tarval_cmp(vrp->range_bottom, new_range_top) == ir_relation_greater) {
491 something_changed = 1;
492 vrp->range_bottom = new_range_top;
494 if (tarval_cmp(vrp->range_top, new_range_bottom) == ir_relation_less) {
495 something_changed = 1;
496 vrp->range_top = new_range_bottom;
501 assert(tarval_is_null(
502 tarval_and(vrp->bits_set, tarval_not(vrp->bits_not_set))));
503 return something_changed;
506 static void vrp_first_pass(ir_node *n, void *e)
509 vrp_env_t *env = (vrp_env_t*) e;
514 bitset_set(env->visited, get_irn_idx(n));
516 vrp_update_node(env->info, 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;