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
31 #include "irgraph_t.h"
39 #include "irphase_t.h"
43 static void *VISITED = &v;
47 DEBUG_ONLY(firm_dbg_module_t *dbg);
50 static vrp_attr *get_vrp_attr(const ir_node *node)
52 return (vrp_attr*) get_or_set_irn_phase_info(node, PHASE_VRP);
55 static int vrp_update_node(ir_node *node)
57 tarval *new_bits_set = get_tarval_bad();
58 tarval *new_bits_not_set = get_tarval_bad();
59 tarval *new_range_bottom = get_tarval_bad();
60 tarval *new_range_top = get_tarval_bad();
61 enum range_types new_range_type = VRP_UNDEFINED;
62 int something_changed = 0;
65 if (!mode_is_int(get_irn_mode(node))) {
66 return 0; /* we don't optimize for non-int-nodes*/
69 vrp = get_vrp_attr(node);
71 /* TODO: Check if all predecessors have valid VRP information*/
73 switch (get_irn_opcode(node)) {
75 tarval *tv = get_Const_tarval(node);
77 new_bits_not_set = tv;
78 new_range_bottom = tv;
80 new_range_type = VRP_RANGE;
84 vrp_attr *vrp_left, *vrp_right;
85 ir_node *left, *right;
87 left = get_And_left(node);
88 right = get_And_right(node);
89 vrp_left = get_vrp_attr(left);
90 vrp_right = get_vrp_attr(right);
91 new_bits_set = tarval_and(vrp_left->bits_set, vrp_right->bits_set);
92 new_bits_not_set = tarval_and(vrp_left->bits_not_set, vrp_right->bits_not_set);
98 int overflow_top, overflow_bottom;
99 tarval *new_top, *new_bottom;
100 vrp_attr *vrp_left, *vrp_right;
101 vrp_left = get_vrp_attr(get_Add_left(node));
102 vrp_right = get_vrp_attr(get_Add_right(node));
104 if (vrp_left->range_type == VRP_UNDEFINED || vrp_right->range_type ==
105 VRP_UNDEFINED || vrp_left->range_type == VRP_VARYING ||
106 vrp_right->range_type == VRP_VARYING) {
110 new_top = tarval_add(vrp_left->range_top, vrp_right->range_top);
111 overflow_top = tarval_carry();
112 new_bottom = tarval_add(vrp_left->range_bottom, vrp_right->range_bottom);
113 overflow_bottom = tarval_carry();
115 if (!overflow_top && !overflow_bottom && vrp_left->range_type == VRP_RANGE
116 &&vrp_right->range_type == VRP_RANGE) {
117 new_range_bottom = new_bottom;
118 new_range_top = new_top;
119 new_range_type = VRP_RANGE;
122 if (overflow_top || overflow_bottom) {
123 /* TODO Implement overflow handling*/
124 new_range_type = VRP_UNDEFINED;
130 int overflow_top, overflow_bottom;
131 tarval *new_top, *new_bottom;
132 vrp_attr *vrp_left, *vrp_right;
133 vrp_left = get_vrp_attr(get_Sub_left(node));
134 vrp_right = get_vrp_attr(get_Sub_right(node));
136 if (vrp_left->range_type == VRP_UNDEFINED || vrp_right->range_type ==
137 VRP_UNDEFINED || vrp_left->range_type == VRP_VARYING ||
138 vrp_right->range_type == VRP_VARYING) {
142 new_top = tarval_sub(vrp_left->range_top, vrp_right->range_top, NULL);
143 overflow_top = tarval_carry();
144 new_bottom = tarval_sub(vrp_left->range_bottom, vrp_right->range_bottom, NULL);
145 overflow_bottom = tarval_carry();
147 if (!overflow_top && !overflow_bottom && vrp_left->range_type == VRP_RANGE
148 &&vrp_right->range_type == VRP_RANGE) {
149 new_range_bottom = new_bottom;
150 new_range_top = new_top;
151 new_range_type = VRP_RANGE;
154 if (overflow_top || overflow_bottom) {
155 /* TODO Implement overflow handling*/
161 vrp_attr *vrp_left, *vrp_right;
163 vrp_left = get_vrp_attr(get_Or_left(node));
164 vrp_right = get_vrp_attr(get_Or_right(node));
166 new_bits_set = tarval_or(vrp_left->bits_set, vrp_right->bits_set);
167 new_bits_not_set = tarval_or(vrp_left->bits_not_set, vrp_right->bits_not_set);
173 vrp_attr *vrp_left, *vrp_right;
174 ir_node *right = get_Rotl_right(node);
176 vrp_left = get_vrp_attr(get_Rotl_left(node));
177 vrp_right = get_vrp_attr(get_Rotl_right(node));
179 /* We can only compute this if the right value is a constant*/
180 if (is_Const(right)) {
181 tarval *bits_set, *bits_not_set;
182 bits_set = tarval_rotl(vrp_left->bits_set, get_Const_tarval(right));
183 bits_not_set = tarval_rotl(vrp_left->bits_not_set, get_Const_tarval(right));
189 vrp_attr *vrp_left, *vrp_right;
190 ir_node *right = get_Shl_right(node);
191 vrp_left = get_vrp_attr(get_Shl_left(node));
192 vrp_right = get_vrp_attr(get_Shl_right(node));
194 /* We can only compute this if the right value is a constant*/
195 if (is_Const(right)) {
196 new_bits_set = tarval_shl(vrp_left->bits_set, get_Const_tarval(right));
197 new_bits_not_set = tarval_shl(vrp_left->bits_not_set, get_Const_tarval(right));
203 vrp_attr *vrp_left, *vrp_right;
204 ir_node *right = get_Shr_right(node);
206 vrp_left = get_vrp_attr(get_Shr_left(node));
207 vrp_right = get_vrp_attr(get_Shr_right(node));
209 /* We can only compute this if the right value is a constant*/
210 if (is_Const(right)) {
211 new_bits_set = tarval_shr(vrp_left->bits_set, get_Const_tarval(right));
212 new_bits_not_set = tarval_shr(vrp_left->bits_not_set, get_Const_tarval(right));
218 vrp_attr *vrp_left, *vrp_right;
219 ir_node *right = get_Shrs_right(node);
221 vrp_left = get_vrp_attr(get_Shrs_left(node));
222 vrp_right = get_vrp_attr(get_Shrs_right(node));
224 /* We can only compute this if the right value is a constant*/
225 if (is_Const(right)) {
226 new_bits_set = tarval_shrs(vrp_left->bits_set, get_Const_tarval(right));
227 new_bits_not_set = tarval_shrs(vrp_left->bits_not_set, get_Const_tarval(right));
233 tarval *bits_set, *bits_not_set;
234 vrp_attr *vrp_left, *vrp_right;
236 vrp_left = get_vrp_attr(get_Eor_left(node));
237 vrp_right = get_vrp_attr(get_Eor_right(node));
239 new_bits_set = tarval_or(
240 tarval_and(vrp_left->bits_set, tarval_not(vrp_right->bits_not_set)),
241 tarval_and(tarval_not(vrp_left->bits_not_set), vrp_right->bits_set));
243 new_bits_not_set = tarval_not(tarval_or(
244 tarval_and(vrp_left->bits_set,vrp_right->bits_set),
245 tarval_and(tarval_not(vrp_left->bits_not_set),
246 tarval_not(vrp_right->bits_not_set))));
252 vrp_attr *vrp_pred = get_vrp_attr(get_Id_pred(node));
253 new_bits_set = vrp_pred->bits_set;
254 new_bits_not_set = vrp_pred->bits_not_set;
255 new_range_top = vrp_pred->range_top;
256 new_range_bottom = vrp_pred->range_bottom;
257 new_range_type = vrp_pred->range_type;
262 vrp_attr *vrp_pred = get_vrp_attr(get_Not_op(node));
263 new_bits_set = tarval_not(vrp_pred->bits_not_set);
264 new_bits_not_set = tarval_not(vrp_pred->bits_set);
269 ir_node *pred = get_Conv_op(node);
270 ir_mode *old_mode = get_irn_mode(pred);
271 vrp_attr *vrp_pred = get_vrp_attr(pred);
275 if (!mode_is_int(old_mode))
278 new_mode = get_irn_mode(node);
280 /* The second and is needed if target type is smaller*/
281 new_bits_not_set = tarval_convert_to(get_mode_all_one(old_mode), new_mode);
282 new_bits_not_set = tarval_and(new_bits_not_set, tarval_convert_to(vrp_pred->bits_not_set, new_mode));
283 new_bits_set = tarval_and(
284 new_bits_not_set, tarval_convert_to(vrp_pred->bits_set, new_mode));
286 if (tarval_cmp(vrp_pred->range_top, get_mode_max(new_mode)) == pn_Cmp_Le) {
287 vrp->range_top = vrp_pred->range_top;
290 if (tarval_cmp(vrp_pred->range_bottom, get_mode_min(new_mode)) == pn_Cmp_Ge) {
291 vrp->range_bottom = vrp_pred->range_bottom;
297 pn_Cmp cmp = get_Confirm_cmp(node);
298 ir_node *bound = get_Confirm_bound(node);
301 if (cmp == pn_Cmp_Lg) {
302 /** @todo: Handle non-Const bounds */
303 if (is_Const(bound)) {
304 new_range_type = VRP_ANTIRANGE;
305 new_range_top = get_Const_tarval(bound);
306 new_range_bottom = get_Const_tarval(bound);
308 } else if (cmp == pn_Cmp_Le) {
309 if (is_Const(bound)) {
310 new_range_type = VRP_RANGE;
311 new_range_top = get_Const_tarval(bound);
312 new_range_bottom = get_tarval_min(get_irn_mode(node));
319 /* combine all ranges*/
321 int num = get_Phi_n_preds(node);
325 ir_node *pred = get_Phi_pred(node,0);
326 vrp_attr *vrp_pred = get_vrp_attr(pred);
327 new_range_top = vrp_pred->range_top;
328 new_range_bottom = vrp_pred->range_bottom;
329 new_range_type = vrp_pred->range_type;
330 new_bits_set = vrp_pred->bits_set;
331 new_bits_not_set = vrp_pred->bits_not_set;
335 for (i = 1; i < num; i++) {
336 pred = get_Phi_pred(node, i);
337 vrp_pred = get_vrp_attr(pred);
338 if (new_range_type == VRP_RANGE && vrp_pred->range_type ==
340 cmp = tarval_cmp(new_range_top, vrp_pred->range_top);
341 if (cmp == pn_Cmp_Lt) {
342 new_range_top = vrp_pred->range_top;
344 cmp = tarval_cmp(new_range_bottom, vrp_pred->range_bottom);
345 if (cmp == pn_Cmp_Gt) {
346 new_range_bottom = vrp_pred->range_bottom;
349 new_range_type = VRP_VARYING;
351 new_bits_set = tarval_and(new_bits_set, vrp_pred->bits_set);
352 new_bits_not_set = tarval_or(new_bits_not_set,
353 vrp_pred->bits_not_set);
359 /* unhandled, therefore never updated */
365 /* TODO: Check, if there can be information derived from any of these:
366 is_Abs(node) is_Alloc(node) is_Anchor(node) is_Borrow(node) is_Bound(node)
367 is_Break(node) is_Builtin(node) is_Call(node) is_CallBegin(node)
368 is_Carry(node) is_Cast(node) is_Cmp(node) is_Cond(node)
369 is_CopyB(node) is_Div(node) is_DivMod(node) is_Dummy(node)
370 is_End(node) is_EndExcept(node) is_EndReg(node) is_Filter(node) is_Free(node)
371 is_IJmp(node) is_InstOf(node) is_Jmp(node) is_Load(node) is_Minus(node)
372 is_Mod(node) is_Mul(node) is_Mulh(node) is_Mux(node) is_NoMem(node)
373 is_Pin(node) is_Proj(node) is_Quot(node)
374 is_Raise(node) is_Return(node) is_Sel(node) is_Start(node) is_Store(node)
375 is_SymConst(node) is_Sync(node) is_Tuple(node)
378 /* @todo: At this place, we check if the mode of the variable changed. A
379 * better place for this might be in the convopt.c file
382 if (new_bits_set != tarval_bad && get_tarval_mode(new_bits_set) != get_tarval_mode(vrp->bits_set)) {
383 vrp->bits_set = tarval_convert_to(vrp->bits_set, get_irn_mode(node));
385 if (new_bits_not_set != tarval_bad && get_tarval_mode(new_bits_not_set) != get_tarval_mode(vrp->bits_not_set)) {
386 vrp->bits_not_set = tarval_convert_to(vrp->bits_not_set, get_irn_mode(node));
389 if (vrp->range_type != VRP_UNDEFINED && new_range_type != VRP_UNDEFINED && get_tarval_mode(new_range_top) != get_tarval_mode(vrp->range_top)) {
390 /* @todo: We might be able to preserve this range information if it
392 vrp->range_type = VRP_VARYING;
395 /* Merge the newly calculated values with those that might already exist*/
396 if (new_bits_set != tarval_bad) {
397 new_bits_set = tarval_or(new_bits_set, vrp->bits_set);
398 if (tarval_cmp(new_bits_set, vrp->bits_set) != pn_Cmp_Eq) {
399 something_changed = 1;
400 vrp->bits_set = new_bits_set;
403 if (new_bits_not_set != tarval_bad) {
404 new_bits_not_set = tarval_and(new_bits_not_set, vrp->bits_not_set);
406 if (tarval_cmp(new_bits_not_set, vrp->bits_not_set) != pn_Cmp_Eq) {
407 something_changed = 1;
408 vrp->bits_not_set = new_bits_not_set;
412 if (vrp->range_type == VRP_UNDEFINED &&
413 new_range_type != VRP_UNDEFINED) {
414 something_changed = 1;
415 vrp->range_type = new_range_type;
416 vrp->range_bottom = new_range_bottom;
417 vrp->range_top = new_range_top;
419 } else if (vrp->range_type == VRP_RANGE) {
420 if (new_range_type == VRP_RANGE) {
421 if (tarval_cmp(vrp->range_bottom, new_range_bottom) == pn_Cmp_Lt) {
422 something_changed = 1;
423 vrp->range_bottom = new_range_bottom;
425 if (tarval_cmp(vrp->range_top, new_range_top) == pn_Cmp_Gt) {
426 something_changed = 1;
427 vrp->range_top = new_range_top;
431 if (new_range_type == VRP_ANTIRANGE) {
432 /* if they are overlapping, cut the range.*/
433 /* TODO: Maybe we can preserve more information here*/
434 if (tarval_cmp(vrp->range_bottom, new_range_top) == pn_Cmp_Gt &&
435 tarval_cmp(vrp->range_bottom, new_range_bottom) == pn_Cmp_Gt) {
436 something_changed = 1;
437 vrp->range_bottom = new_range_top;
439 } else if (tarval_cmp(vrp->range_top, new_range_bottom) == pn_Cmp_Gt &&
440 tarval_cmp(vrp->range_top, new_range_top) == pn_Cmp_Lt) {
441 something_changed = 1;
442 vrp->range_top = new_range_bottom;
445 /* We can not handle the case where the anti range is in the*/
449 } else if (vrp->range_type == VRP_ANTIRANGE) {
450 if (new_range_type == VRP_ANTIRANGE) {
451 if (tarval_cmp(vrp->range_bottom, new_range_bottom) == pn_Cmp_Gt) {
452 something_changed = 1;
453 vrp->range_bottom = new_range_bottom;
455 if (tarval_cmp(vrp->range_top, new_range_top) == pn_Cmp_Lt) {
456 something_changed = 1;
457 vrp->range_top = new_range_top;
461 if (new_range_type == VRP_RANGE) {
462 if (tarval_cmp(vrp->range_bottom, new_range_top) == pn_Cmp_Gt) {
463 something_changed = 1;
464 vrp->range_bottom = new_range_top;
466 if (tarval_cmp(vrp->range_top, new_range_bottom) == pn_Cmp_Lt) {
467 something_changed = 1;
468 vrp->range_top = new_range_bottom;
473 assert(tarval_is_null(
474 tarval_and(vrp->bits_set, tarval_not(vrp->bits_not_set))));
475 return something_changed;
478 static void vrp_first_pass(ir_node *n, void *e)
482 struct vrp_env_t *env = e;
487 set_irn_link(n, VISITED);
491 assure_irg_outs(get_current_ir_graph());
492 for (i = get_irn_n_outs(n) - 1; i >=0; --i) {
493 succ = get_irn_out(n, i);
494 if (get_irn_link(succ) == VISITED) {
496 waitq_put(env->workqueue, succ);
501 static void *vrp_init_node(ir_phase *phase, const ir_node *n, void *old)
505 struct vrp_env_t *env = phase->priv;
507 DBG((env->dbg, LEVEL_2, "initialized node nr: %d\n", get_irn_node_nr(n)));
508 assert(old==NULL && "init called for node already initialized");
509 vrp = phase_alloc(phase, sizeof(vrp_attr));
511 memset(vrp, 0, sizeof(vrp_attr));
512 /* Initialize the vrp information to default */
514 mode = get_irn_mode(n);
516 vrp->range_type = VRP_UNDEFINED;
518 /* TODO: We might be able to optimize space usage if we do not allocate
519 * vrp space for non-int nodes. (currently caught by vrp_update_node)
521 if (mode_is_int(mode)) {
522 /* We are assuming that 0 is always represented as this modes null */
524 vrp->bits_set = get_mode_null(mode);
525 vrp->bits_not_set = get_mode_all_one(mode);
526 vrp->range_bottom = get_tarval_top();
527 vrp->range_top = get_tarval_top();
530 vrp->bits_set = get_tarval_bad();
531 vrp->bits_not_set = get_tarval_bad();
532 vrp->range_bottom = get_tarval_bad();
533 vrp->range_top = get_tarval_bad();
536 /* TODO: We might be able to set better vrp info at this time, if this is
537 * a node which is newly created in an already initialized irg
539 * maybe just call vrp_update_node and if it returns one, iterate over
545 void set_vrp_data(ir_graph *irg)
547 ir_node *succ, *node;
549 struct vrp_env_t *env;
552 assure_irg_outs(irg); /* ensure that out edges are consistent*/
553 phase = irg_get_phase(irg, PHASE_VRP);
555 /* this is our first run */
556 phase = new_phase(irg, vrp_init_node);
557 irg_register_phase(irg, PHASE_VRP, phase);
558 env = phase_alloc(phase, sizeof(*env));
559 FIRM_DBG_REGISTER(env->dbg, "ir.ana.vrp");
565 env->workqueue = new_waitq();
567 irg_walk_graph(irg, NULL, vrp_first_pass, env);
569 /* while there are entries in the worklist, continue*/
570 while (!waitq_empty(env->workqueue)) {
571 node = waitq_get(env->workqueue);
573 if (vrp_update_node(node)) {
574 /* if something changed, add successors to worklist*/
575 for (i = get_irn_n_outs(node) - 1; i >=0; --i) {
576 succ = get_irn_out(node, i);
577 waitq_put(env->workqueue, node);
581 del_waitq(env->workqueue);
585 ir_graph_pass_t *set_vrp_pass(const char *name)
587 return def_graph_pass(name ? name : "set_vrp", set_vrp_data);
590 pn_Cmp vrp_cmp(const ir_node *left, const ir_node *right)
592 vrp_attr *vrp_left, *vrp_right;
594 vrp_left = vrp_get_info(left);
595 vrp_right = vrp_get_info(right);
597 if (!vrp_left || !vrp_right) {
601 if (vrp_left->range_type == VRP_RANGE && vrp_right->range_type == VRP_RANGE) {
602 if (tarval_cmp(vrp_left->range_top, vrp_right->range_bottom) == pn_Cmp_Lt) {
605 if (tarval_cmp(vrp_left->range_bottom, vrp_right->range_top) == pn_Cmp_Gt) {
610 if (!tarval_is_null(tarval_and(vrp_left->bits_set, tarval_not(vrp_right->bits_not_set))) ||
611 !tarval_is_null(tarval_and(tarval_not(vrp_left->bits_not_set), vrp_right->bits_set))) {
614 /* TODO: We can get way more information here*/
619 vrp_attr *vrp_get_info(const ir_node *node)
621 const ir_graph *irg = get_irn_irg(node);
622 const ir_phase *phase = irg_get_phase(irg, PHASE_VRP);
625 /* phase has not yet been initialized */
630 vrp_attr *vrp = phase_get_irn_data(phase, node);
631 if (vrp && vrp->valid) {