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
30 #include "iroptimize.h"
32 #include "irgraph_t.h"
40 #include "irnodemap.h"
45 DEBUG_ONLY(static firm_dbg_module_t *dbg;)
47 typedef struct vrp_env_t {
53 static vrp_attr *vrp_get_or_set_info(ir_vrp_info *info, const ir_node *node)
55 vrp_attr *attr = ir_nodemap_get(&info->infos, node);
57 ir_mode *mode = get_irn_mode(node);
58 assert(mode_is_int(mode));
60 attr = obstack_alloc(&info->obst, sizeof(*attr));
61 memset(attr, 0, sizeof(*attr));
62 attr->range_type = VRP_UNDEFINED;
63 attr->bits_set = get_mode_null(mode);
64 attr->bits_not_set = get_mode_all_one(mode);
65 attr->range_bottom = get_tarval_top();
66 attr->range_top = get_tarval_top();
68 ir_nodemap_insert(&info->infos, node, attr);
73 vrp_attr *vrp_get_info(const ir_node *node)
75 ir_graph *irg = get_irn_irg(node);
76 if (irg->vrp.infos.data == NULL)
78 return (vrp_attr*) ir_nodemap_get(&irg->vrp.infos, node);
81 static int vrp_update_node(ir_vrp_info *info, ir_node *node)
83 ir_tarval *new_bits_set = get_tarval_bad();
84 ir_tarval *new_bits_not_set = get_tarval_bad();
85 ir_tarval *new_range_bottom = get_tarval_bad();
86 ir_tarval *new_range_top = get_tarval_bad();
87 enum range_types new_range_type = VRP_UNDEFINED;
88 int something_changed = 0;
91 if (!mode_is_int(get_irn_mode(node))) {
92 return 0; /* we don't optimize for non-int-nodes*/
95 vrp = vrp_get_or_set_info(info, node);
97 /* TODO: Check if all predecessors have valid VRP information*/
99 switch (get_irn_opcode(node)) {
101 ir_tarval *tv = get_Const_tarval(node);
103 new_bits_not_set = tv;
104 new_range_bottom = tv;
106 new_range_type = VRP_RANGE;
110 const vrp_attr *vrp_left, *vrp_right;
111 const ir_node *left, *right;
113 left = get_And_left(node);
114 right = get_And_right(node);
115 vrp_left = vrp_get_or_set_info(info, left);
116 vrp_right = vrp_get_or_set_info(info, right);
117 new_bits_set = tarval_and(vrp_left->bits_set, vrp_right->bits_set);
118 new_bits_not_set = tarval_and(vrp_left->bits_not_set, vrp_right->bits_not_set);
124 int overflow_top, overflow_bottom;
125 ir_tarval *new_top, *new_bottom;
126 const vrp_attr *vrp_left, *vrp_right;
127 vrp_left = vrp_get_or_set_info(info, get_Add_left(node));
128 vrp_right = vrp_get_or_set_info(info, get_Add_right(node));
130 if (vrp_left->range_type == VRP_UNDEFINED || vrp_right->range_type ==
131 VRP_UNDEFINED || vrp_left->range_type == VRP_VARYING ||
132 vrp_right->range_type == VRP_VARYING) {
136 new_top = tarval_add(vrp_left->range_top, vrp_right->range_top);
137 overflow_top = tarval_carry();
138 new_bottom = tarval_add(vrp_left->range_bottom, vrp_right->range_bottom);
139 overflow_bottom = tarval_carry();
141 if (!overflow_top && !overflow_bottom && vrp_left->range_type == VRP_RANGE
142 &&vrp_right->range_type == VRP_RANGE) {
143 new_range_bottom = new_bottom;
144 new_range_top = new_top;
145 new_range_type = VRP_RANGE;
148 if (overflow_top || overflow_bottom) {
149 /* TODO Implement overflow handling*/
150 new_range_type = VRP_UNDEFINED;
156 ir_node *left = get_Sub_left(node);
157 ir_node *right = get_Sub_right(node);
158 int overflow_top, overflow_bottom;
159 ir_tarval *new_top, *new_bottom;
160 const vrp_attr *vrp_left, *vrp_right;
162 if (!mode_is_int(get_irn_mode(left)))
165 vrp_left = vrp_get_or_set_info(info, left);
166 vrp_right = vrp_get_or_set_info(info, right);
168 if (vrp_left->range_type == VRP_UNDEFINED || vrp_right->range_type ==
169 VRP_UNDEFINED || vrp_left->range_type == VRP_VARYING ||
170 vrp_right->range_type == VRP_VARYING) {
174 new_top = tarval_sub(vrp_left->range_top, vrp_right->range_top, NULL);
175 overflow_top = tarval_carry();
176 new_bottom = tarval_sub(vrp_left->range_bottom, vrp_right->range_bottom, NULL);
177 overflow_bottom = tarval_carry();
179 if (!overflow_top && !overflow_bottom && vrp_left->range_type == VRP_RANGE
180 &&vrp_right->range_type == VRP_RANGE) {
181 new_range_bottom = new_bottom;
182 new_range_top = new_top;
183 new_range_type = VRP_RANGE;
186 if (overflow_top || overflow_bottom) {
187 /* TODO Implement overflow handling*/
193 const vrp_attr *vrp_left, *vrp_right;
195 vrp_left = vrp_get_or_set_info(info, get_Or_left(node));
196 vrp_right = vrp_get_or_set_info(info, get_Or_right(node));
198 new_bits_set = tarval_or(vrp_left->bits_set, vrp_right->bits_set);
199 new_bits_not_set = tarval_or(vrp_left->bits_not_set, vrp_right->bits_not_set);
205 const vrp_attr *vrp_left;
206 const ir_node *right = get_Rotl_right(node);
208 vrp_left = vrp_get_or_set_info(info, get_Rotl_left(node));
210 /* We can only compute this if the right value is a constant*/
211 if (is_Const(right)) {
212 new_bits_set = tarval_rotl(vrp_left->bits_set, get_Const_tarval(right));
213 new_bits_not_set = tarval_rotl(vrp_left->bits_not_set, get_Const_tarval(right));
219 const vrp_attr *vrp_left;
220 const ir_node *right = get_Shl_right(node);
221 vrp_left = vrp_get_or_set_info(info, get_Shl_left(node));
223 /* We can only compute this if the right value is a constant*/
224 if (is_Const(right)) {
225 new_bits_set = tarval_shl(vrp_left->bits_set, get_Const_tarval(right));
226 new_bits_not_set = tarval_shl(vrp_left->bits_not_set, get_Const_tarval(right));
232 const vrp_attr *vrp_left;
233 const ir_node *right = get_Shr_right(node);
235 vrp_left = vrp_get_or_set_info(info, get_Shr_left(node));
237 /* We can only compute this if the right value is a constant*/
238 if (is_Const(right)) {
239 new_bits_set = tarval_shr(vrp_left->bits_set, get_Const_tarval(right));
240 new_bits_not_set = tarval_shr(vrp_left->bits_not_set, get_Const_tarval(right));
246 const vrp_attr *vrp_left;
247 const ir_node *right = get_Shrs_right(node);
249 vrp_left = vrp_get_or_set_info(info, get_Shrs_left(node));
251 /* We can only compute this if the right value is a constant*/
252 if (is_Const(right)) {
253 new_bits_set = tarval_shrs(vrp_left->bits_set, get_Const_tarval(right));
254 new_bits_not_set = tarval_shrs(vrp_left->bits_not_set, get_Const_tarval(right));
260 const vrp_attr *vrp_left, *vrp_right;
262 vrp_left = vrp_get_or_set_info(info, get_Eor_left(node));
263 vrp_right = vrp_get_or_set_info(info, get_Eor_right(node));
265 new_bits_set = tarval_or(
266 tarval_and(vrp_left->bits_set, tarval_not(vrp_right->bits_not_set)),
267 tarval_and(tarval_not(vrp_left->bits_not_set), vrp_right->bits_set));
269 new_bits_not_set = tarval_not(tarval_or(
270 tarval_and(vrp_left->bits_set,vrp_right->bits_set),
271 tarval_and(tarval_not(vrp_left->bits_not_set),
272 tarval_not(vrp_right->bits_not_set))));
278 const vrp_attr *vrp_pred = vrp_get_or_set_info(info, get_Id_pred(node));
279 new_bits_set = vrp_pred->bits_set;
280 new_bits_not_set = vrp_pred->bits_not_set;
281 new_range_top = vrp_pred->range_top;
282 new_range_bottom = vrp_pred->range_bottom;
283 new_range_type = vrp_pred->range_type;
288 const vrp_attr *vrp_pred = vrp_get_or_set_info(info, get_Not_op(node));
289 new_bits_set = tarval_not(vrp_pred->bits_not_set);
290 new_bits_not_set = tarval_not(vrp_pred->bits_set);
295 const ir_node *pred = get_Conv_op(node);
296 ir_mode *old_mode = get_irn_mode(pred);
297 const vrp_attr *vrp_pred;
301 if (!mode_is_int(old_mode))
304 vrp_pred = vrp_get_or_set_info(info, pred);
305 new_mode = get_irn_mode(node);
307 /* The second and is needed if target type is smaller*/
308 new_bits_not_set = tarval_convert_to(get_mode_all_one(old_mode), new_mode);
309 new_bits_not_set = tarval_and(new_bits_not_set, tarval_convert_to(vrp_pred->bits_not_set, new_mode));
310 new_bits_set = tarval_and(
311 new_bits_not_set, tarval_convert_to(vrp_pred->bits_set, new_mode));
313 /* Matze: TODO, BUGGY, tarval_cmp never returns ir_relation_less_equal */
314 if (tarval_cmp(vrp_pred->range_top, get_mode_max(new_mode)) == ir_relation_less_equal) {
315 vrp->range_top = vrp_pred->range_top;
318 /* Matze: TODO, BUGGY, tarval_cmp never returns ir_relation_greater_equal */
319 if (tarval_cmp(vrp_pred->range_bottom, get_mode_min(new_mode)) == ir_relation_greater_equal) {
320 vrp->range_bottom = vrp_pred->range_bottom;
326 const ir_relation relation = get_Confirm_relation(node);
327 const ir_node *bound = get_Confirm_bound(node);
330 if (relation == ir_relation_less_greater) {
331 /** @todo: Handle non-Const bounds */
332 if (is_Const(bound)) {
333 new_range_type = VRP_ANTIRANGE;
334 new_range_top = get_Const_tarval(bound);
335 new_range_bottom = get_Const_tarval(bound);
337 } else if (relation == ir_relation_less_equal) {
338 if (is_Const(bound)) {
339 new_range_type = VRP_RANGE;
340 new_range_top = get_Const_tarval(bound);
341 new_range_bottom = get_tarval_min(get_irn_mode(node));
348 /* combine all ranges*/
350 int num = get_Phi_n_preds(node);
351 ir_relation relation;
354 const ir_node *pred = get_Phi_pred(node,0);
355 const vrp_attr *vrp_pred = vrp_get_or_set_info(info, pred);
356 new_range_top = vrp_pred->range_top;
357 new_range_bottom = vrp_pred->range_bottom;
358 new_range_type = vrp_pred->range_type;
359 new_bits_set = vrp_pred->bits_set;
360 new_bits_not_set = vrp_pred->bits_not_set;
364 for (i = 1; i < num; i++) {
365 pred = get_Phi_pred(node, i);
366 vrp_pred = vrp_get_or_set_info(info, pred);
367 if (new_range_type == VRP_RANGE && vrp_pred->range_type ==
369 relation = tarval_cmp(new_range_top, vrp_pred->range_top);
370 if (relation == ir_relation_less) {
371 new_range_top = vrp_pred->range_top;
373 relation = tarval_cmp(new_range_bottom, vrp_pred->range_bottom);
374 if (relation == ir_relation_greater) {
375 new_range_bottom = vrp_pred->range_bottom;
378 new_range_type = VRP_VARYING;
380 new_bits_set = tarval_and(new_bits_set, vrp_pred->bits_set);
381 new_bits_not_set = tarval_or(new_bits_not_set,
382 vrp_pred->bits_not_set);
388 /* unhandled, therefore never updated */
394 /* TODO: Check, if there can be information derived from any of these:
395 is_Abs(node) is_Alloc(node) is_Anchor(node) is_Borrow(node) is_Bound(node)
396 is_Break(node) is_Builtin(node) is_Call(node)
397 is_Carry(node) is_Cast(node) is_Cmp(node) is_Cond(node)
398 is_CopyB(node) is_Div(node) is_Dummy(node)
399 is_End(node) is_Free(node)
400 is_IJmp(node) is_InstOf(node) is_Jmp(node) is_Load(node) is_Minus(node)
401 is_Mod(node) is_Mul(node) is_Mulh(node) is_Mux(node) is_NoMem(node)
402 is_Pin(node) is_Proj(node)
403 is_Raise(node) is_Return(node) is_Sel(node) is_Start(node) is_Store(node)
404 is_SymConst(node) is_Sync(node) is_Tuple(node)
407 /* @todo: At this place, we check if the mode of the variable changed. A
408 * better place for this might be in the convopt.c file
411 if (new_bits_set != tarval_bad && get_tarval_mode(new_bits_set) != get_tarval_mode(vrp->bits_set)) {
412 vrp->bits_set = tarval_convert_to(vrp->bits_set, get_irn_mode(node));
414 if (new_bits_not_set != tarval_bad && get_tarval_mode(new_bits_not_set) != get_tarval_mode(vrp->bits_not_set)) {
415 vrp->bits_not_set = tarval_convert_to(vrp->bits_not_set, get_irn_mode(node));
418 if (vrp->range_type != VRP_UNDEFINED && new_range_type != VRP_UNDEFINED && get_tarval_mode(new_range_top) != get_tarval_mode(vrp->range_top)) {
419 /* @todo: We might be able to preserve this range information if it
421 vrp->range_type = VRP_VARYING;
424 /* Merge the newly calculated values with those that might already exist*/
425 if (new_bits_set != tarval_bad) {
426 new_bits_set = tarval_or(new_bits_set, vrp->bits_set);
427 if (tarval_cmp(new_bits_set, vrp->bits_set) != ir_relation_equal) {
428 something_changed = 1;
429 vrp->bits_set = new_bits_set;
432 if (new_bits_not_set != tarval_bad) {
433 new_bits_not_set = tarval_and(new_bits_not_set, vrp->bits_not_set);
435 if (tarval_cmp(new_bits_not_set, vrp->bits_not_set) != ir_relation_equal) {
436 something_changed = 1;
437 vrp->bits_not_set = new_bits_not_set;
441 if (vrp->range_type == VRP_UNDEFINED &&
442 new_range_type != VRP_UNDEFINED) {
443 something_changed = 1;
444 vrp->range_type = new_range_type;
445 vrp->range_bottom = new_range_bottom;
446 vrp->range_top = new_range_top;
448 } else if (vrp->range_type == VRP_RANGE) {
449 if (new_range_type == VRP_RANGE) {
450 if (tarval_cmp(vrp->range_bottom, new_range_bottom) == ir_relation_less) {
451 something_changed = 1;
452 vrp->range_bottom = new_range_bottom;
454 if (tarval_cmp(vrp->range_top, new_range_top) == ir_relation_greater) {
455 something_changed = 1;
456 vrp->range_top = new_range_top;
460 if (new_range_type == VRP_ANTIRANGE) {
461 /* if they are overlapping, cut the range.*/
462 /* TODO: Maybe we can preserve more information here*/
463 if (tarval_cmp(vrp->range_bottom, new_range_top) == ir_relation_greater &&
464 tarval_cmp(vrp->range_bottom, new_range_bottom) == ir_relation_greater) {
465 something_changed = 1;
466 vrp->range_bottom = new_range_top;
468 } else if (tarval_cmp(vrp->range_top, new_range_bottom) == ir_relation_greater &&
469 tarval_cmp(vrp->range_top, new_range_top) == ir_relation_less) {
470 something_changed = 1;
471 vrp->range_top = new_range_bottom;
474 /* We can not handle the case where the anti range is in the*/
478 } else if (vrp->range_type == VRP_ANTIRANGE) {
479 if (new_range_type == VRP_ANTIRANGE) {
480 if (tarval_cmp(vrp->range_bottom, new_range_bottom) == ir_relation_greater) {
481 something_changed = 1;
482 vrp->range_bottom = new_range_bottom;
484 if (tarval_cmp(vrp->range_top, new_range_top) == ir_relation_less) {
485 something_changed = 1;
486 vrp->range_top = new_range_top;
490 if (new_range_type == VRP_RANGE) {
491 if (tarval_cmp(vrp->range_bottom, new_range_top) == ir_relation_greater) {
492 something_changed = 1;
493 vrp->range_bottom = new_range_top;
495 if (tarval_cmp(vrp->range_top, new_range_bottom) == ir_relation_less) {
496 something_changed = 1;
497 vrp->range_top = new_range_bottom;
502 assert(tarval_is_null(
503 tarval_and(vrp->bits_set, tarval_not(vrp->bits_not_set))));
504 return something_changed;
507 static void vrp_first_pass(ir_node *n, void *e)
510 vrp_env_t *env = (vrp_env_t*) e;
515 bitset_set(env->visited, get_irn_idx(n));
517 vrp_update_node(env->info, n);
519 assure_irg_outs(get_current_ir_graph());
520 for (i = get_irn_n_outs(n) - 1; i >=0; --i) {
521 ir_node *succ = get_irn_out(n, i);
522 if (bitset_is_set(env->visited, get_irn_idx(succ))) {
524 waitq_put(env->workqueue, succ);
529 static void dump_vrp_info(void *ctx, FILE *F, const ir_node *node)
534 if (!mode_is_int(get_irn_mode(node)))
537 vrp = vrp_get_info(node);
541 fprintf(F, "vrp range type: %d\n", (int) vrp->range_type);
542 if (vrp->range_type == VRP_RANGE || vrp->range_type == VRP_ANTIRANGE) {
543 ir_fprintf(F, "vrp range bottom: %T\n",vrp->range_bottom);
544 ir_fprintf(F, "vrp range top: %T\n", vrp->range_top);
546 ir_fprintf(F, "vrp bits set: %T\n", vrp->bits_set);
547 ir_fprintf(F, "vrp bits not set: %T\n", vrp->bits_not_set);
550 static hook_entry_t dump_hook;
552 void set_vrp_data(ir_graph *irg)
554 ir_node *succ, *node;
559 if (irg->vrp.infos.data != NULL)
562 FIRM_DBG_REGISTER(dbg, "ir.ana.vrp");
564 assure_irg_outs(irg); /* ensure that out edges are consistent*/
565 ir_nodemap_init(&irg->vrp.infos, irg);
566 obstack_init(&irg->vrp.obst);
569 if (dump_hook.hook._hook_node_info == NULL) {
570 dump_hook.hook._hook_node_info = dump_vrp_info;
571 register_hook(hook_node_info, &dump_hook);
574 env = obstack_alloc(&irg->vrp.obst, sizeof(*env));
575 env->workqueue = new_waitq();
578 env->visited = bitset_malloc(get_irg_last_idx(irg));
579 irg_walk_graph(irg, NULL, vrp_first_pass, env);
580 bitset_free(env->visited);
582 /* while there are entries in the worklist, continue*/
583 while (!waitq_empty(env->workqueue)) {
584 node = (ir_node*) waitq_get(env->workqueue);
586 if (vrp_update_node(info, node)) {
587 /* if something changed, add successors to worklist*/
588 for (i = get_irn_n_outs(node) - 1; i >= 0; --i) {
589 succ = get_irn_out(node, i);
590 waitq_put(env->workqueue, succ);
594 del_waitq(env->workqueue);
597 void free_vrp_data(ir_graph *irg)
599 if (irg->vrp.infos.data == NULL)
601 obstack_free(&irg->vrp.obst, NULL);
602 ir_nodemap_destroy(&irg->vrp.infos);
605 ir_graph_pass_t *set_vrp_pass(const char *name)
607 return def_graph_pass(name ? name : "set_vrp", set_vrp_data);
610 ir_relation vrp_cmp(const ir_node *left, const ir_node *right)
612 vrp_attr *vrp_left, *vrp_right;
614 if (!mode_is_int(get_irn_mode(left)))
615 return ir_relation_true;
617 vrp_left = vrp_get_info(left);
618 vrp_right = vrp_get_info(right);
620 if (!vrp_left || !vrp_right)
621 return ir_relation_true;
623 if (vrp_left->range_type == VRP_RANGE && vrp_right->range_type == VRP_RANGE) {
624 if (tarval_cmp(vrp_left->range_top, vrp_right->range_bottom) == ir_relation_less) {
625 return ir_relation_less;
627 if (tarval_cmp(vrp_left->range_bottom, vrp_right->range_top) == ir_relation_greater) {
628 return ir_relation_greater;
632 if (!tarval_is_null(tarval_and(vrp_left->bits_set, tarval_not(vrp_right->bits_not_set))) ||
633 !tarval_is_null(tarval_and(tarval_not(vrp_left->bits_not_set), vrp_right->bits_set))) {
634 return ir_relation_less_greater;
637 /* TODO: We can get way more information here*/
638 return ir_relation_true;