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4 * This file is part of libFirm.
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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 boolean condition/control flow optimizations
23 * @author Matthias Braun, Christoph Mallon, Michael Beck
24 * @version $Id: cfopt.c 22579 2008-10-07 14:54:04Z beck $
32 #include "../adt/array_t.h"
33 #include "iroptimize.h"
43 /** Describes a pair of relative conditions lo < hi, lo pnc_lo x, hi pnc_hi x */
44 typedef struct cond_pair {
45 ir_node *cmp_lo; /**< The lo compare node. */
46 ir_node *cmp_hi; /**< The hi compare node. */
47 pn_Cmp pnc_lo; /**< The lo relation node. */
48 pn_Cmp pnc_hi; /**< The hi relation node. */
49 ir_node *proj_lo; /**< The mode_b result proj of cmp_lo. */
50 ir_node *proj_hi; /**< The mode_b result proj of cmp_hi. */
51 tarval *tv_lo; /**< The tarval of cmp_lo node. */
52 tarval *tv_hi; /**< The tarval of cmp_hi node. */
53 ir_mode *lo_mode; /**< The mode of the cmp_lo operands. */
56 /** Environment for all walker in boolopt. */
58 int changed; /**< Set if the graph was changed. */
61 DEBUG_ONLY(static firm_dbg_module_t *dbg);
64 * Check if tho given nodes, l and r, represent two compares with
65 * ... . If yes, return non-zero and fill the res struct.
67 static int find_cond_pair(ir_node *const l, ir_node *const r, cond_pair *const res)
69 if (is_Proj(l) && is_Proj(r)) {
70 ir_node *const lo = get_Proj_pred(l);
71 ir_node *const ro = get_Proj_pred(r);
73 if (is_Cmp(lo) && is_Cmp(ro)) {
74 ir_node *const lol = get_Cmp_left(lo);
75 ir_node *const lor = get_Cmp_right(lo);
76 ir_node *const rol = get_Cmp_left(ro);
77 ir_node *const ror = get_Cmp_right(ro);
78 pn_Cmp const pnc_l = get_Proj_proj(l);
79 pn_Cmp const pnc_r = get_Proj_proj(r);
81 if (is_Const(lor) && is_Const_null(lor) &&
82 is_Const(ror) && is_Const_null(ror) &&
84 (pnc_l == pn_Cmp_Lg || pnc_l == pn_Cmp_Eq)) {
85 /* lo == (lol !=|== NULL) && ro == (rol !=|== NULL) */
86 DB((dbg, LEVEL_1, "found <null null>\n"));
94 res->tv_lo = get_Const_tarval(lor);
95 res->tv_hi = get_Const_tarval(ror);
96 res->lo_mode = get_irn_mode(lor);
101 if (lol == rol && lor != ror && is_Const(lor) && is_Const(ror)) {
102 /* lo == (x CMP c_l), ro == (x cmp c_r) */
103 tarval *const tv_l = get_Const_tarval(lor);
104 tarval *const tv_r = get_Const_tarval(ror);
105 pn_Cmp const rel = tarval_cmp(tv_l, tv_r);
107 res->lo_mode = get_irn_mode(lol);
109 if (rel == pn_Cmp_Lt) {
119 } else if (rel == pn_Cmp_Gt) {
130 /* The constants shall be unequal but comparable.
131 * Local optimizations handle the equal case. */
142 * Handle (lo pnc_lo x) AND (hi pnc_hi x)
144 static ir_node *bool_and(cond_pair* const cpair)
146 ir_node *const cmp_lo = cpair->cmp_lo;
147 ir_node *const cmp_hi = cpair->cmp_hi;
148 pn_Cmp pnc_lo = cpair->pnc_lo;
149 pn_Cmp const pnc_hi = cpair->pnc_hi;
150 ir_node *const proj_lo = cpair->proj_lo;
151 ir_node *const proj_hi = cpair->proj_hi;
152 tarval * tv_lo = cpair->tv_lo;
153 tarval * tv_hi = cpair->tv_hi;
154 ir_mode * mode = cpair->lo_mode;
156 if (mode_is_reference(mode) && pnc_lo == pn_Cmp_Eq && pnc_hi == pn_Cmp_Eq &&
157 tarval_is_null(tv_lo) && tarval_is_null(tv_hi) &&
158 mode == get_tarval_mode(tv_hi)) {
159 /* p == NULL && q == NULL ==> (p&q) == NULL) */
160 ir_node *block, *lol, *hil, *cmp, *c, *p;
162 mode = find_unsigned_mode(mode);
165 tv_lo = tarval_convert_to(tv_lo, mode);
166 if (tv_lo == tarval_bad)
168 block = get_nodes_block(cmp_lo);
169 lol = get_Cmp_left(cmp_lo);
170 lol = new_r_Conv(block, lol, mode);
171 hil = get_Cmp_left(cmp_hi);
172 hil = new_r_Conv(block, hil, mode);
173 p = new_r_And(block, lol, hil, mode);
174 c = new_Const(tv_lo);
175 cmp = new_r_Cmp(block, p, c);
176 p = new_r_Proj(block, cmp, mode_b, pn_Cmp_Eq);
180 /* TODO: for now reject float modes */
181 if (! mode_is_int(mode))
184 /* Beware of NaN's, we can only check for (ordered) != here (which is Lg, not Ne) */
185 if ((pnc_lo == pn_Cmp_Lt || pnc_lo == pn_Cmp_Le || pnc_lo == pn_Cmp_Eq) &&
186 (pnc_hi == pn_Cmp_Eq || pnc_hi == pn_Cmp_Ge || pnc_hi == pn_Cmp_Gt)) {
187 /* x <|<=|== lo && x ==|>=|> hi ==> false */
188 ir_node *const t = new_Const(tarval_b_false);
190 } else if ((pnc_lo == pn_Cmp_Lt || pnc_lo == pn_Cmp_Le || pnc_lo == pn_Cmp_Eq) &&
191 (pnc_hi == pn_Cmp_Lt || pnc_hi == pn_Cmp_Le || pnc_hi == pn_Cmp_Lg)) {
192 /* x <|<=|== lo && x <|<=|!= hi ==> x <|<=|== lo */
194 } else if ((pnc_lo == pn_Cmp_Ge || pnc_lo == pn_Cmp_Gt || pnc_lo == pn_Cmp_Lg) &&
195 (pnc_hi == pn_Cmp_Eq || pnc_hi == pn_Cmp_Ge || pnc_hi == pn_Cmp_Gt)) {
196 /* x >=|>|!= lo && x ==|>=|> hi ==> x ==|>=|> hi */
198 } else if (tarval_is_one(tarval_sub(tv_hi, tv_lo, NULL))) { /* lo + 1 == hi */
199 if (pnc_lo == pn_Cmp_Ge && pnc_hi == pn_Cmp_Lt) {
200 /* x >= c && x < c + 1 ==> x == c */
201 ir_node *const block = get_nodes_block(cmp_lo);
202 ir_node *const p = new_r_Proj(block, cmp_lo, mode_b, pn_Cmp_Eq);
204 } else if (pnc_lo == pn_Cmp_Gt) {
205 if (pnc_hi == pn_Cmp_Lg) {
206 /* x > c && x != c + 1 ==> x > c + 1 */
207 ir_node *const block = get_nodes_block(cmp_hi);
208 ir_node *const p = new_r_Proj(block, cmp_hi, mode_b, pn_Cmp_Gt);
210 } else if (pnc_hi == pn_Cmp_Lt) {
211 /* x > c && x < c + 1 ==> false */
212 ir_node *const t = new_Const(tarval_b_false);
214 } else if (pnc_hi == pn_Cmp_Le) {
215 /* x > c && x <= c + 1 ==> x != c + 1 */
216 ir_node *const block = get_nodes_block(cmp_hi);
217 ir_node *const p = new_r_Proj(block, cmp_hi, mode_b, pn_Cmp_Eq);
220 } else if (pnc_lo == pn_Cmp_Lg && pnc_hi == pn_Cmp_Lt) {
221 /* x != c && c < c + 1 ==> x < c */
222 ir_node *const block = get_nodes_block(cmp_lo);
223 ir_node *const p = new_r_Proj(block, cmp_lo, mode_b, pn_Cmp_Lt);
226 } else if ((pnc_lo == pn_Cmp_Gt || pnc_lo == pn_Cmp_Ge) &&
227 (pnc_hi == pn_Cmp_Lt || pnc_lo == pn_Cmp_Le) &&
228 get_mode_arithmetic(mode) == irma_twos_complement) {
229 /* works for two-complements only */
230 /* x >|\= lo && x <|<= hi ==> (x - lo) <u|<=u (hi-lo) */
231 if (pnc_lo == pn_Cmp_Gt) {
232 /* must convert to >= */
233 ir_mode *mode = get_tarval_mode(tv_lo);
234 tarval *n = tarval_add(tv_lo, get_mode_one(mode));
235 if (n != tarval_bad && tarval_cmp(n, tv_lo) == pn_Cmp_Gt) {
241 if (pnc_lo == pn_Cmp_Ge) {
243 ir_node *const block = get_nodes_block(cmp_hi);
244 ir_node * x = get_Cmp_left(cmp_hi);
245 ir_mode * mode = get_irn_mode(x);
246 ir_node *sub, *cmp, *c, *subc, *p;
248 if (mode_is_signed(mode)) {
249 /* convert to unsigned */
250 mode = find_unsigned_mode(mode);
253 x = new_r_Conv(block, x, mode);
254 tv_lo = tarval_convert_to(tv_lo, mode);
255 tv_hi = tarval_convert_to(tv_hi, mode);
256 if (tv_lo == tarval_bad || tv_hi == tarval_bad)
259 c = new_Const(tv_lo);
260 sub = new_r_Sub(block, x, c, mode);
261 subc = new_r_Sub(block, new_Const(tv_hi), c, mode);
262 cmp = new_r_Cmp(block, sub, subc);
263 p = new_r_Proj(block, cmp, mode_b, pnc_hi);
271 * Handle (lo pnc_lo x) OR (hi pnc_hi x)
273 static ir_node *bool_or(cond_pair *const cpair)
275 ir_node *const cmp_lo = cpair->cmp_lo;
276 ir_node *const cmp_hi = cpair->cmp_hi;
277 pn_Cmp pnc_lo = cpair->pnc_lo;
278 pn_Cmp const pnc_hi = cpair->pnc_hi;
279 ir_node *const proj_lo = cpair->proj_lo;
280 ir_node *const proj_hi = cpair->proj_hi;
281 tarval * tv_lo = cpair->tv_lo;
282 tarval * tv_hi = cpair->tv_hi;
283 ir_mode * mode = cpair->lo_mode;
285 if (mode_is_reference(mode) && pnc_lo == pn_Cmp_Lg && pnc_hi == pn_Cmp_Lg &&
286 tarval_is_null(tv_lo) && tarval_is_null(tv_hi) &&
287 mode == get_tarval_mode(tv_hi)) {
288 /* p != NULL || q != NULL ==> (p|q) != NULL) */
289 ir_node *block, *lol, *hil, *cmp, *c, *p;
291 mode = find_unsigned_mode(mode);
294 tv_lo = tarval_convert_to(tv_lo, mode);
295 if (tv_lo == tarval_bad)
297 block = get_nodes_block(cmp_lo);
298 lol = get_Cmp_left(cmp_lo);
299 lol = new_r_Conv(block, lol, mode);
300 hil = get_Cmp_left(cmp_hi);
301 hil = new_r_Conv(block, hil, mode);
302 p = new_r_Or(block, lol, hil, mode);
303 c = new_Const(tv_lo);
304 cmp = new_r_Cmp(block, p, c);
305 p = new_r_Proj(block, cmp, mode_b, pn_Cmp_Lg);
309 /* TODO: for now reject float modes */
310 if (! mode_is_int(mode))
313 /* Beware of NaN's, we can only check for (ordered) != here (which is Lg, not Ne) */
314 if ((pnc_lo == pn_Cmp_Ge || pnc_lo == pn_Cmp_Gt || pnc_lo == pn_Cmp_Lg) &&
315 (pnc_hi == pn_Cmp_Lt || pnc_hi == pn_Cmp_Le || pnc_hi == pn_Cmp_Lg)) {
316 /* x >=|>|!= lo | x <|<=|!= hi ==> true */
317 ir_node *const t = new_Const(tarval_b_true);
319 } else if ((pnc_lo == pn_Cmp_Lt || pnc_lo == pn_Cmp_Le || pnc_lo == pn_Cmp_Eq) &&
320 (pnc_hi == pn_Cmp_Lt || pnc_hi == pn_Cmp_Le || pnc_hi == pn_Cmp_Lg)) {
321 /* x <|<=|== lo || x <|<=|!= hi ==> x <|<=|!= hi */
323 } else if ((pnc_lo == pn_Cmp_Ge || pnc_lo == pn_Cmp_Gt || pnc_lo == pn_Cmp_Lg) &&
324 (pnc_hi == pn_Cmp_Eq || pnc_hi == pn_Cmp_Ge || pnc_hi == pn_Cmp_Gt)) {
325 /* x >=|>|!= lo || x ==|>=|> hi ==> x >=|>|!= lo */
327 } else if (tarval_is_one(tarval_sub(tv_hi, tv_lo, NULL))) { /* lo + 1 == hi */
328 if (pnc_lo == pn_Cmp_Lt && pnc_hi == pn_Cmp_Ge) {
329 /* x < c || x >= c + 1 ==> x != c */
330 ir_node *const block = get_nodes_block(cmp_lo);
331 ir_node *const p = new_r_Proj(block, cmp_lo, mode_b, pn_Cmp_Lg);
333 } else if (pnc_lo == pn_Cmp_Le) {
334 if (pnc_hi == pn_Cmp_Eq) {
335 /* x <= c || x == c + 1 ==> x <= c + 1 */
336 ir_node *const block = get_nodes_block(cmp_hi);
337 ir_node *const p = new_r_Proj(block, cmp_hi, mode_b, pn_Cmp_Le);
339 } else if (pnc_hi == pn_Cmp_Ge) {
340 /* x <= c || x >= c + 1 ==> true */
341 ir_node *const t = new_Const(tarval_b_true);
343 } else if (pnc_hi == pn_Cmp_Gt) {
344 /* x <= c || x > c + 1 ==> x != c + 1 */
345 ir_node *const block = get_nodes_block(cmp_hi);
346 ir_node *const p = new_r_Proj(block, cmp_hi, mode_b, pn_Cmp_Lg);
349 } else if (pnc_lo == pn_Cmp_Eq && pnc_hi == pn_Cmp_Ge) {
350 /* x == c || x >= c + 1 ==> x >= c */
351 ir_node *const block = get_nodes_block(cmp_lo);
352 ir_node *const p = new_r_Proj(block, cmp_lo, mode_b, pn_Cmp_Ge);
355 } else if ((pnc_lo == pn_Cmp_Lt || pnc_lo == pn_Cmp_Le) &&
356 (pnc_hi == pn_Cmp_Gt || pnc_lo == pn_Cmp_Ge) &&
357 get_mode_arithmetic(mode) == irma_twos_complement) {
358 /* works for two-complements only */
359 /* x <|\= lo || x >|>= hi ==> (x - lo) >u|>=u (hi-lo) */
360 if (pnc_lo == pn_Cmp_Lt) {
361 /* must convert to <= */
362 ir_mode *mode = get_tarval_mode(tv_lo);
363 tarval *n = tarval_sub(tv_lo, get_mode_one(mode), NULL);
364 if (n != tarval_bad && tarval_cmp(n, tv_lo) == pn_Cmp_Lt) {
370 if (pnc_lo == pn_Cmp_Le) {
372 ir_node *const block = get_nodes_block(cmp_hi);
373 ir_node * x = get_Cmp_left(cmp_hi);
374 ir_mode * mode = get_irn_mode(x);
375 ir_node *sub, *cmp, *c, *subc, *p;
377 if (mode_is_signed(mode)) {
378 /* convert to unsigned */
379 mode = find_unsigned_mode(mode);
382 x = new_r_Conv(block, x, mode);
383 tv_lo = tarval_convert_to(tv_lo, mode);
384 tv_hi = tarval_convert_to(tv_hi, mode);
385 if (tv_lo == tarval_bad || tv_hi == tarval_bad)
388 c = new_Const(tv_lo);
389 sub = new_r_Sub(block, x, c, mode);
390 subc = new_r_Sub(block, new_Const(tv_hi), c, mode);
391 cmp = new_r_Cmp(block, sub, subc);
392 p = new_r_Proj(block, cmp, mode_b, pnc_hi);
400 * Walker, tries to optimize Andb and Orb nodes.
402 static void bool_walk(ir_node *n, void *ctx)
404 bool_opt_env_t *env = ctx;
406 if (get_irn_mode(n) != mode_b)
410 ir_node *const l = get_And_left(n);
411 ir_node *const r = get_And_right(n);
412 ir_node * replacement;
414 if (!find_cond_pair(l, r, &cpair))
416 replacement = bool_and(&cpair);
418 exchange(n, replacement);
421 } else if (is_Or(n)) {
422 ir_node *const l = get_Or_left(n);
423 ir_node *const r = get_Or_right(n);
424 ir_node * replacement;
426 if (!find_cond_pair(l, r, &cpair))
428 replacement = bool_or(&cpair);
430 exchange(n, replacement);
437 * Walker, clear Block marker and Phi lists.
439 static void clear_block_infos(ir_node *node, void *env)
443 /* we visit blocks before any other nodes (from the block) */
447 /* clear the PHI list */
448 set_Block_phis(node, NULL);
449 set_Block_mark(node, 0);
453 * Walker: collect Phi nodes and mark
455 static void collect_phis(ir_node *node, void *env)
460 ir_node *block = get_nodes_block(node);
461 add_Block_phi(block, node);
465 /* Ignore control flow nodes, these will be removed. */
466 if (get_irn_pinned(node) == op_pin_state_pinned &&
467 !is_Block(node) && !is_cfop(node)) {
468 /* found a pinned non-cf node, mark its block */
469 ir_node *block = get_nodes_block(node);
470 set_Block_mark(block, 1);
475 * If node is a Jmp in a block containing no pinned instruction
476 * and having only one predecessor, skip the block and return its
477 * cf predecessor, else the node itself.
479 static ir_node *skip_empty_blocks(ir_node *node)
481 while (is_Jmp(node)) {
482 ir_node *block = get_nodes_block(node);
484 if (get_Block_n_cfgpreds(block) != 1)
487 if (get_Block_mark(block))
490 node = get_Block_cfgpred(block, 0);
496 * Check if two block inputs can be fused.
497 * This can be done, if block contains no Phi node that depends on
498 * different inputs idx_i and idx_j.
500 static int can_fuse_block_inputs(const ir_node *block, int idx_i, int idx_j) {
503 for (phi = get_Block_phis(block); phi != NULL; phi = get_Phi_next(phi)) {
504 if (get_Phi_pred(phi, idx_i) != get_Phi_pred(phi, idx_j))
511 * Remove block input with given index.
513 static void remove_block_input(ir_node *block, int idx)
515 int i, j, n = get_Block_n_cfgpreds(block) - 1;
518 NEW_ARR_A(ir_node *, ins, n);
521 /* all Phis will be deleted */
524 for (phi = get_Block_phis(block); phi != NULL; phi = next_phi) {
525 next_phi = get_Phi_next(phi);
526 exchange(phi, get_Phi_pred(phi, idx ^ 1));
528 set_Block_phis(block, NULL);
530 for (phi = get_Block_phis(block); phi != NULL; phi = get_Phi_next(phi)) {
531 for (i = j = 0; i <= n; ++i) {
533 ins[j++] = get_Phi_pred(phi, i);
535 set_irn_in(phi, n, ins);
538 for (i = j = 0; i <= n; ++i) {
540 ins[j++] = get_Block_cfgpred(block, i);
542 set_irn_in(block, n, ins);
546 * Under the preposition that we have a chain of blocks from
547 * from_block to to_block, collapse them all into to_block.
549 static void move_nodes_to_block(ir_node *jmp, ir_node *to_block) {
550 ir_node *new_jmp = NULL;
551 ir_node *block, *next_block;
553 for (block = get_nodes_block(jmp); block != to_block; block = next_block) {
554 new_jmp = get_Block_cfgpred(block, 0);
555 next_block = get_nodes_block(new_jmp);
556 exchange(block, to_block);
559 exchange(jmp, new_jmp);
565 * if we can find the following structure,
576 * try to convert it into a (x pnc_lo c_lo) || (x pnc_hi c_hi)
579 static void find_cf_and_or_walker(ir_node *block, void *ctx)
582 int n_cfgpreds = get_Block_n_cfgpreds(block);
583 bool_opt_env_t *env = ctx;
589 for (low_idx = 0; low_idx < n_cfgpreds; ++low_idx) {
590 ir_node *lower_block;
593 ir_node *cond_selector;
596 lower_cf = get_Block_cfgpred(block, low_idx);
597 lower_cf = skip_empty_blocks(lower_cf);
598 if (!is_Proj(lower_cf))
601 cond = get_Proj_pred(lower_cf);
605 lower_block = get_nodes_block(cond);
606 if (get_Block_n_cfgpreds(lower_block) != 1)
609 /* the block must not produce any side-effects */
610 if (get_Block_mark(lower_block))
613 cond_selector = get_Cond_selector(cond);
614 if (get_irn_mode(cond_selector) != mode_b)
617 lower_pred = get_Block_cfgpred_block(lower_block, 0);
619 for (up_idx = 0; up_idx < n_cfgpreds; ++up_idx) {
620 ir_node *upper_block;
623 ir_node *upper_cond_selector;
624 ir_node *replacement;
627 upper_cf = get_Block_cfgpred(block, up_idx);
628 upper_cf = skip_empty_blocks(upper_cf);
629 if (is_Bad(upper_cf))
631 upper_block = get_nodes_block(upper_cf);
632 if (upper_block != lower_pred)
635 assert(is_Proj(upper_cf));
636 upper_cond = get_Proj_pred(upper_cf);
637 assert(is_Cond(upper_cond));
638 upper_cond_selector = get_Cond_selector(upper_cond);
639 if (get_irn_mode(upper_cond_selector) != mode_b)
642 /* we have found the structure */
643 /* check Phis: There must be NO Phi in block that
644 depends on the existence of low block */
645 if (!can_fuse_block_inputs(block, low_idx, up_idx))
648 /* all fine, try it */
649 if (!find_cond_pair(cond_selector, upper_cond_selector, &cpair))
652 /* normalize pncs: we need the true case to jump into the
653 * common block (ie. conjunctive normal form) */
654 if (get_Proj_proj(lower_cf) == pn_Cond_false) {
655 if (cpair.proj_lo == cond_selector) {
656 ir_mode *mode = get_tarval_mode(cpair.tv_lo);
657 cpair.pnc_lo = get_negated_pnc(cpair.pnc_lo, mode);
658 cpair.proj_lo = new_r_Proj(lower_block,
659 get_Proj_pred(cpair.proj_lo), mode_b, cpair.pnc_lo);
661 ir_mode *mode = get_tarval_mode(cpair.tv_hi);
662 assert(cpair.proj_hi == cond_selector);
663 cpair.pnc_hi = get_negated_pnc(cpair.pnc_hi, mode);
664 cpair.proj_hi = new_r_Proj(lower_block,
665 get_Proj_pred(cpair.proj_hi), mode_b, cpair.pnc_hi);
668 if (get_Proj_proj(upper_cf) == pn_Cond_false) {
669 if (cpair.proj_lo == upper_cond_selector) {
670 ir_mode *mode = get_tarval_mode(cpair.tv_lo);
671 cpair.pnc_lo = get_negated_pnc(cpair.pnc_lo, mode);
672 cpair.proj_lo = new_r_Proj(upper_block,
673 get_Proj_pred(cpair.proj_lo), mode_b, cpair.pnc_lo);
675 ir_mode *mode = get_tarval_mode(cpair.tv_hi);
676 assert(cpair.proj_hi == upper_cond_selector);
677 cpair.pnc_hi = get_negated_pnc(cpair.pnc_hi, mode);
678 cpair.proj_hi = new_r_Proj(upper_block,
679 get_Proj_pred(cpair.proj_hi), mode_b, cpair.pnc_hi);
683 /* can we optimize the case? */
684 replacement = bool_or(&cpair);
685 if (replacement == NULL)
690 /* move all expressions on the path to lower/upper block */
691 move_nodes_to_block(get_Block_cfgpred(block, up_idx), upper_block);
692 move_nodes_to_block(get_Block_cfgpred(block, low_idx), lower_block);
694 /* move all nodes from lower block to upper block */
695 exchange(lower_block, upper_block);
697 remove_block_input(block, up_idx);
700 /* the optimizations expected the true case to jump */
701 if (get_Proj_proj(lower_cf) == pn_Cond_false) {
702 ir_node *block = get_nodes_block(replacement);
703 replacement = new_rd_Not(NULL, block, replacement, mode_b);
705 set_Cond_selector(cond, replacement);
707 DB((dbg, LEVEL_1, "%+F: replaced (ub %+F)\n", current_ir_graph, upper_block));
713 void opt_bool(ir_graph *const irg)
717 /* register a debug mask */
718 FIRM_DBG_REGISTER(dbg, "firm.opt.bool");
720 /* works better with one return block only */
721 normalize_one_return(irg);
725 /* optimize simple Andb and Orb cases */
726 irg_walk_graph(irg, NULL, bool_walk, &env);
728 ir_reserve_resources(irg, IR_RESOURCE_BLOCK_MARK | IR_RESOURCE_PHI_LIST);
730 /* now more complicated cases: find control flow And/Or and optimize. */
731 irg_walk_graph(irg, clear_block_infos, collect_phis, NULL);
732 irg_block_walk_graph(irg, NULL, find_cf_and_or_walker, &env);
735 set_irg_outs_inconsistent(irg);
736 set_irg_doms_inconsistent(irg);
737 set_irg_extblk_inconsistent(irg);
738 set_irg_loopinfo_inconsistent(irg);
741 ir_free_resources(irg, IR_RESOURCE_BLOCK_MARK | IR_RESOURCE_PHI_LIST);
744 /* Creates an ir_graph pass for opt_bool. */
745 ir_graph_pass_t *opt_bool_pass(const char *name)
747 return def_graph_pass(name ? name : "opt_bool", opt_bool);
748 } /* opt_bool_pass */