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 Various verify routines that check a scheduled graph for correctness.
23 * @author Matthias Braun
47 #include "beintlive_t.h"
49 static int my_values_interfere(const ir_node *a, const ir_node *b);
51 typedef struct be_verify_register_pressure_env_t_ {
52 ir_graph *irg; /**< the irg to verify */
53 be_lv_t *lv; /**< Liveness information. */
54 const arch_register_class_t *cls; /**< the register class to check for */
55 int registers_available; /**< number of available registers */
56 int problem_found; /**< flag indicating if a problem was found */
57 } be_verify_register_pressure_env_t;
60 * Print all nodes of a pset into a file.
62 static void print_living_values(FILE *F, const ir_nodeset_t *live_nodes)
64 ir_nodeset_iterator_t iter;
68 foreach_ir_nodeset(live_nodes, node, iter) {
69 ir_fprintf(F, "%+F ", node);
75 * Check if number of live nodes never exceeds the number of available registers.
77 static void verify_liveness_walker(ir_node *block, void *data)
79 be_verify_register_pressure_env_t *env = (be_verify_register_pressure_env_t *)data;
80 ir_nodeset_t live_nodes;
84 /* collect register pressure info, start with end of a block */
85 // ir_fprintf(stderr, "liveness check %+F\n", block);
86 ir_nodeset_init(&live_nodes);
87 be_liveness_end_of_block(env->lv, env->cls, block,
90 // print_living_values(stderr, &live_nodes);
91 pressure = ir_nodeset_size(&live_nodes);
92 if (pressure > env->registers_available) {
93 ir_fprintf(stderr, "Verify Warning: Register pressure too high at end of block %+F(%s) (%d/%d):\n",
94 block, get_irg_dump_name(env->irg), pressure, env->registers_available);
95 print_living_values(stderr, &live_nodes);
96 env->problem_found = 1;
99 sched_foreach_reverse(block, irn) {
103 // print_living_values(stderr, &live_nodes);
104 be_liveness_transfer(env->cls, irn, &live_nodes);
106 pressure = ir_nodeset_size(&live_nodes);
108 if (pressure > env->registers_available) {
109 ir_fprintf(stderr, "Verify Warning: Register pressure too high before node %+F in %+F(%s) (%d/%d):\n",
110 irn, block, get_irg_dump_name(env->irg), pressure, env->registers_available);
111 print_living_values(stderr, &live_nodes);
112 env->problem_found = 1;
116 ir_nodeset_destroy(&live_nodes);
120 * Start a walk over the irg and check the register pressure.
122 int be_verify_register_pressure(ir_graph *irg, const arch_register_class_t *cls)
124 be_verify_register_pressure_env_t env;
126 env.lv = be_liveness(irg);
129 env.registers_available
130 = env.cls->n_regs - be_put_ignore_regs(irg, env.cls, NULL);
131 env.problem_found = 0;
133 be_liveness_assure_sets(env.lv);
134 irg_block_walk_graph(irg, verify_liveness_walker, NULL, &env);
135 be_liveness_free(env.lv);
137 return ! env.problem_found;
142 /*--------------------------------------------------------------------------- */
146 typedef struct be_verify_schedule_env_t_ {
147 int problem_found; /**< flags indicating a problem */
148 bitset_t *scheduled; /**< bitset of scheduled nodes */
149 ir_graph *irg; /**< the irg to check */
150 } be_verify_schedule_env_t;
153 * Simple schedule checker.
155 static void verify_schedule_walker(ir_node *block, void *data)
157 be_verify_schedule_env_t *env = (be_verify_schedule_env_t*) data;
159 ir_node *non_phi_found = NULL;
160 int cfchange_found = 0;
161 /* TODO ask arch about delay branches */
162 int delay_branches = 0;
163 int last_timestep = INT_MIN;
166 * Tests for the following things:
167 * 1. Make sure that all phi nodes are scheduled at the beginning of the block
168 * 2. There is 1 or no control flow changing node scheduled and exactly delay_branches operations after it.
169 * 3. No value is defined after it has been used
170 * 4. mode_T nodes have all projs scheduled behind them followed by Keeps
171 * (except mode_X projs)
173 sched_foreach(block, node) {
177 /* this node is scheduled */
178 if (bitset_is_set(env->scheduled, get_irn_idx(node))) {
179 ir_fprintf(stderr, "Verify warning: %+F appears to be schedule twice\n");
180 env->problem_found = 1;
182 bitset_set(env->scheduled, get_irn_idx(node));
184 /* Check that scheduled nodes are in the correct block */
185 if (get_nodes_block(node) != block) {
186 ir_fprintf(stderr, "Verify warning: %+F is in block %+F but scheduled in %+F\n", node, get_nodes_block(node), block);
187 env->problem_found = 1;
190 /* Check that timesteps are increasing */
191 timestep = sched_get_time_step(node);
192 if (timestep <= last_timestep) {
193 ir_fprintf(stderr, "Verify warning: Schedule timestep did not increase at node %+F\n",
195 env->problem_found = 1;
197 last_timestep = timestep;
199 /* Check that phis come before any other node */
201 if (non_phi_found != NULL) {
202 ir_fprintf(stderr, "Verify Warning: Phi node %+F scheduled after non-Phi nodes (for example %+F) in block %+F (%s)\n",
203 node, non_phi_found, block, get_irg_dump_name(env->irg));
204 env->problem_found = 1;
207 non_phi_found = node;
210 /* Check for control flow changing nodes */
211 if (is_cfop(node) && get_irn_opcode(node) != iro_Start) {
212 /* check, that only one CF operation is scheduled */
213 if (cfchange_found == 1) {
214 ir_fprintf(stderr, "Verify Warning: More than 1 control flow changing node (%+F) scheduled in block %+F (%s)\n",
215 node, block, get_irg_dump_name(env->irg));
216 env->problem_found = 1;
219 } else if (cfchange_found) {
220 /* proj and keepany aren't real instructions... */
221 if (!is_Proj(node) && !be_is_Keep(node)) {
222 /* check for delay branches */
223 if (delay_branches == 0) {
224 ir_fprintf(stderr, "Verify Warning: Node %+F scheduled after control flow changing node (+delay branches) in block %+F (%s)\n",
225 node, block, get_irg_dump_name(env->irg));
226 env->problem_found = 1;
233 /* Check that all uses come before their definitions */
235 int nodetime = sched_get_time_step(node);
236 for (i = 0, arity = get_irn_arity(node); i < arity; ++i) {
237 ir_node *arg = get_irn_n(node, i);
238 if (get_nodes_block(arg) != block
239 || !sched_is_scheduled(arg))
242 if (sched_get_time_step(arg) >= nodetime) {
243 ir_fprintf(stderr, "Verify Warning: Value %+F used by %+F before it was defined in block %+F (%s)\n",
244 arg, node, block, get_irg_dump_name(env->irg));
245 env->problem_found = 1;
250 /* Check that no dead nodes are scheduled */
251 if (get_irn_n_edges(node) == 0) {
252 ir_fprintf(stderr, "Verify warning: Node %+F is dead but scheduled in block %+F (%s)\n",
253 node, block, get_irg_dump_name(env->irg));
254 env->problem_found = 1;
257 if (be_is_Keep(node) || be_is_CopyKeep(node)) {
258 /* at least 1 of the keep arguments has to be it schedule
260 int arity = get_irn_arity(node);
262 ir_node *prev = sched_prev(node);
263 while (be_is_Keep(prev) || be_is_CopyKeep(prev))
264 prev = sched_prev(prev);
266 for (i = 0; i < arity; ++i) {
267 ir_node *in = get_irn_n(node, i);
273 ir_fprintf(stderr, "%+F not scheduled after its pred node in block %+F (%s)\n",
274 node, block, get_irg_dump_name(env->irg));
275 env->problem_found = 1;
280 /* check that all delay branches are filled (at least with NOPs) */
281 if (cfchange_found && delay_branches != 0) {
282 ir_fprintf(stderr, "Verify warning: Not all delay slots filled after jump (%d/%d) in block %+F (%s)\n",
283 block, get_irg_dump_name(env->irg));
284 env->problem_found = 1;
288 static void check_schedule(ir_node *node, void *data)
290 be_verify_schedule_env_t *env = data;
291 bool should_be = to_appear_in_schedule(node);
292 bool scheduled = bitset_is_set(env->scheduled, get_irn_idx(node));
294 if (should_be != scheduled) {
295 ir_fprintf(stderr, "Verify warning: Node %+F in block %+F(%s) should%s be scheduled\n",
296 node, get_nodes_block(node), get_irg_dump_name(env->irg), should_be ? "" : " not");
297 env->problem_found = 1;
302 * Start a walk over the irg and check schedule.
304 int be_verify_schedule(ir_graph *irg)
306 be_verify_schedule_env_t env;
308 env.problem_found = 0;
310 env.scheduled = bitset_alloca(get_irg_last_idx(env.irg));
312 irg_block_walk_graph(irg, verify_schedule_walker, NULL, &env);
313 /* check if all nodes are scheduled */
314 irg_walk_graph(irg, check_schedule, NULL, &env);
316 return ! env.problem_found;
321 /*--------------------------------------------------------------------------- */
325 typedef struct spill_t {
335 } be_verify_spillslots_env_t;
337 static int cmp_spill(const void* d1, const void* d2, size_t size)
339 const spill_t* s1 = d1;
340 const spill_t* s2 = d2;
343 return s1->spill != s2->spill;
346 static spill_t *find_spill(be_verify_spillslots_env_t *env, ir_node *node)
351 return set_find(env->spills, &spill, sizeof(spill), HASH_PTR(node));
354 static spill_t *get_spill(be_verify_spillslots_env_t *env, ir_node *node, ir_entity *ent)
357 int hash = HASH_PTR(node);
360 res = set_find(env->spills, &spill, sizeof(spill), hash);
364 res = set_insert(env->spills, &spill, sizeof(spill), hash);
370 static ir_node *get_memory_edge(const ir_node *node)
373 ir_node *result = NULL;
375 arity = get_irn_arity(node);
376 for (i = arity - 1; i >= 0; --i) {
377 ir_node *arg = get_irn_n(node, i);
378 if (get_irn_mode(arg) == mode_M) {
379 assert(result == NULL);
387 static void collect(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, ir_entity* ent);
389 static void be_check_entity(be_verify_spillslots_env_t *env, ir_node *node, ir_entity *ent)
392 ir_fprintf(stderr, "Verify warning: Node %+F in block %+F(%s) should have an entity assigned\n",
393 node, get_nodes_block(node), get_irg_dump_name(env->irg));
397 static void collect_spill(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, ir_entity* ent)
399 ir_entity *spillent = arch_get_frame_entity(node);
400 be_check_entity(env, node, spillent);
401 get_spill(env, node, ent);
403 if (spillent != ent) {
404 ir_fprintf(stderr, "Verify warning: Spill %+F has different entity than reload %+F in block %+F(%s)\n",
405 node, reload, get_nodes_block(node), get_irg_dump_name(env->irg));
406 env->problem_found = 1;
410 static void collect_memperm(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, ir_entity* ent)
414 int hash = HASH_PTR(node);
419 assert(is_Proj(node));
421 memperm = get_Proj_pred(node);
422 out = get_Proj_proj(node);
424 spillent = be_get_MemPerm_out_entity(memperm, out);
425 be_check_entity(env, memperm, spillent);
426 if (spillent != ent) {
427 ir_fprintf(stderr, "Verify warning: MemPerm %+F has different entity than reload %+F in block %+F(%s)\n",
428 node, reload, get_nodes_block(node), get_irg_dump_name(env->irg));
429 env->problem_found = 1;
433 res = set_find(env->spills, &spill, sizeof(spill), hash);
438 spill.ent = spillent;
439 res = set_insert(env->spills, &spill, sizeof(spill), hash);
441 for (i = 0, arity = be_get_MemPerm_entity_arity(memperm); i < arity; ++i) {
442 ir_node* arg = get_irn_n(memperm, i + 1);
443 ir_entity* argent = be_get_MemPerm_in_entity(memperm, i);
445 collect(env, arg, memperm, argent);
449 static void collect_memphi(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, ir_entity *ent)
453 int hash = HASH_PTR(node);
455 assert(is_Phi(node));
458 res = set_find(env->spills, &spill, sizeof(spill), hash);
464 res = set_insert(env->spills, &spill, sizeof(spill), hash);
466 /* is 1 of the arguments a spill? */
467 for (i = 0, arity = get_irn_arity(node); i < arity; ++i) {
468 ir_node* arg = get_irn_n(node, i);
469 collect(env, arg, reload, ent);
473 static void collect(be_verify_spillslots_env_t *env, ir_node *node, ir_node *reload, ir_entity* ent)
475 if (be_is_Spill(node)) {
476 collect_spill(env, node, reload, ent);
477 } else if (is_Proj(node)) {
478 collect_memperm(env, node, reload, ent);
479 } else if (is_Phi(node) && get_irn_mode(node) == mode_M) {
480 collect_memphi(env, node, reload, ent);
482 /* Disabled for now, spills might get transformed by the backend */
484 ir_fprintf(stderr, "Verify warning: No spill, memperm or memphi attached to node %+F found from node %+F in block %+F(%s)\n",
485 node, reload, get_nodes_block(node), get_irg_dump_name(env->irg));
486 env->problem_found = 1;
492 * This walker function searches for reloads and collects all the spills
493 * and memphis attached to them.
495 static void collect_spills_walker(ir_node *node, void *data)
497 be_verify_spillslots_env_t *env = data;
499 if (arch_irn_classify(node) & arch_irn_class_reload) {
500 ir_node *spill = get_memory_edge(node);
504 ir_fprintf(stderr, "Verify warning: No spill attached to reload %+F in block %+F(%s)\n",
505 node, get_nodes_block(node), get_irg_dump_name(env->irg));
506 env->problem_found = 1;
509 ent = arch_get_frame_entity(node);
510 be_check_entity(env, node, ent);
512 collect(env, spill, node, ent);
513 ARR_APP1(ir_node*, env->reloads, node);
517 static void check_spillslot_interference(be_verify_spillslots_env_t *env)
519 int spillcount = set_count(env->spills);
520 spill_t **spills = ALLOCAN(spill_t*, spillcount);
524 for (spill = set_first(env->spills), i = 0; spill != NULL; spill = set_next(env->spills), ++i) {
528 for (i = 0; i < spillcount; ++i) {
529 spill_t *sp1 = spills[i];
532 for (i2 = i+1; i2 < spillcount; ++i2) {
533 spill_t *sp2 = spills[i2];
535 if (sp1->ent != sp2->ent)
538 if (my_values_interfere(sp1->spill, sp2->spill)) {
539 ir_fprintf(stderr, "Verify warning: Spillslots for %+F in block %+F(%s) and %+F in block %+F(%s) interfere\n",
540 sp1->spill, get_nodes_block(sp1->spill), get_irg_dump_name(env->irg),
541 sp2->spill, get_nodes_block(sp2->spill), get_irg_dump_name(env->irg));
542 env->problem_found = 1;
543 my_values_interfere(sp1->spill, sp2->spill);
549 static void check_lonely_spills(ir_node *node, void *data)
551 be_verify_spillslots_env_t *env = data;
553 if (be_is_Spill(node) || (is_Proj(node) && be_is_MemPerm(get_Proj_pred(node)))) {
554 spill_t *spill = find_spill(env, node);
555 if (be_is_Spill(node)) {
556 ir_entity *ent = arch_get_frame_entity(node);
557 be_check_entity(env, node, ent);
561 ir_fprintf(stderr, "Verify warning: Node %+F in block %+F(%s) not connected to a reaload\n",
562 node, get_nodes_block(node), get_irg_dump_name(env->irg));
567 int be_verify_spillslots(ir_graph *irg)
569 be_verify_spillslots_env_t env;
572 env.spills = new_set(cmp_spill, 10);
573 env.reloads = NEW_ARR_F(ir_node*, 0);
574 env.problem_found = 0;
576 irg_walk_graph(irg, collect_spills_walker, NULL, &env);
577 irg_walk_graph(irg, check_lonely_spills, NULL, &env);
579 check_spillslot_interference(&env);
581 DEL_ARR_F(env.reloads);
584 return ! env.problem_found;
589 /*--------------------------------------------------------------------------- */
594 * Check, if two values interfere.
595 * @param a The first value.
596 * @param b The second value.
597 * @return 1, if a and b interfere, 0 if not.
599 static int my_values_interfere(const ir_node *a, const ir_node *b)
601 const ir_edge_t *edge;
603 int a2b = value_dominates(a, b);
604 int b2a = value_dominates(b, a);
606 /* If there is no dominance relation, they do not interfere. */
611 * Adjust a and b so, that a dominates b if
612 * a dominates b or vice versa.
615 const ir_node *t = a;
620 bb = get_nodes_block(b);
623 * Look at all usages of a.
624 * If there's one usage of a in the block of b, then
625 * we check, if this use is dominated by b, if that's true
626 * a and b interfere. Note that b must strictly dominate the user,
627 * since if b is the last user of in the block, b and a do not
629 * Uses of a not in b's block can be disobeyed, because the
630 * check for a being live at the end of b's block is already
633 foreach_out_edge(a, edge) {
634 const ir_node *user = get_edge_src_irn(edge);
638 if (get_irn_opcode(user) == iro_End)
641 /* in case of phi arguments we compare with the block the value comes from */
643 ir_node *phiblock = get_nodes_block(user);
646 user = get_irn_n(phiblock, get_edge_src_pos(edge));
649 if (value_dominates(b, user))
658 /*--------------------------------------------------------------------------- */
660 static const arch_env_t *arch_env;
661 static ir_graph *irg;
663 static int problem_found;
664 static const arch_register_class_t *regclass;
665 static ir_node **registers;
667 static void check_output_constraints(ir_node *node)
669 /* verify output register */
670 if (arch_get_irn_reg_class_out(node) == regclass) {
671 const arch_register_t *reg = arch_get_irn_register(node);
673 ir_fprintf(stderr, "Verify warning: Node %+F in block %+F(%s) should have a register assigned\n",
674 node, get_nodes_block(node), get_irg_dump_name(irg));
676 } else if (!arch_register_type_is(reg, joker) && !arch_reg_out_is_allocatable(node, reg)) {
677 ir_fprintf(stderr, "Verify warning: Register %s assigned as output of %+F not allowed (register constraint) in block %+F(%s)\n",
678 reg->name, node, get_nodes_block(node), get_irg_dump_name(irg));
684 static void check_input_constraints(ir_node *node)
686 const arch_register_t *reg;
689 /* verify input register */
690 arity = get_irn_arity(node);
691 for (i = 0; i < arity; ++i) {
692 const arch_register_req_t *req = arch_get_in_register_req(node, i);
693 ir_node *pred = get_irn_n(node, i);
694 const arch_register_req_t *pred_req = arch_get_register_req_out(pred);
697 ir_fprintf(stderr, "Verify warning: %+F in block %+F(%s) has Bad as input %d\n",
698 node, get_nodes_block(node), get_irg_dump_name(irg), i);
702 if (req->cls == NULL)
705 if (req->width > pred_req->width) {
706 ir_fprintf(stderr, "Verify warning: %+F in block %+F(%s) register width of value at input %d too small\n",
707 node, get_nodes_block(node), get_irg_dump_name(irg), i);
711 reg = arch_get_irn_register(pred);
712 if (req->type & arch_register_req_type_aligned) {
713 if (reg->index % req->width != 0) {
714 ir_fprintf(stderr, "Verify warning: %+F in block %+F(%s) register allignment not fulfilled\n",
715 node, get_nodes_block(node), get_irg_dump_name(irg), i);
721 ir_fprintf(stderr, "Verify warning: Node %+F in block %+F(%s) should have a register assigned (%+F input constraint)\n",
722 pred, get_nodes_block(pred), get_irg_dump_name(irg), node);
725 } else if (!arch_register_type_is(reg, joker) && ! arch_reg_is_allocatable(node, i, reg)) {
726 ir_fprintf(stderr, "Verify warning: Register %s as input %d of %+F not allowed (register constraint) in block %+F(%s)\n",
727 reg->name, i, node, get_nodes_block(node), get_irg_dump_name(irg));
732 /* phis should be NOPs at this point, which means all input regs
733 * must be the same as the output reg */
737 reg = arch_get_irn_register(node);
739 arity = get_irn_arity(node);
740 for (i = 0; i < arity; ++i) {
741 ir_node *pred = get_Phi_pred(node, i);
742 const arch_register_t *pred_reg = arch_get_irn_register(pred);
744 if (reg != pred_reg && !arch_register_type_is(pred_reg, joker)) {
745 const char *pred_name = pred_reg != NULL ? pred_reg->name : "(null)";
746 const char *reg_name = reg != NULL ? reg->name : "(null)";
747 ir_fprintf(stderr, "Verify warning: Input %d of %+F in block %+F(%s) uses register %s instead of %s\n",
748 i, node, get_nodes_block(node),
749 get_irg_dump_name(irg), pred_name, reg_name);
756 static void value_used(ir_node *block, ir_node *node)
758 const arch_register_t *reg;
761 if (arch_get_irn_reg_class_out(node) != regclass)
764 reg = arch_get_irn_register(node);
765 if (reg == NULL || reg->type & arch_register_type_virtual)
768 reg_node = registers[reg->index];
769 if (reg_node != NULL && reg_node != node) {
770 ir_fprintf(stderr, "Verify warning: Register %s assigned more than once in block %+F(%s) (nodes %+F %+F)\n",
771 reg->name, block, get_irg_dump_name(irg),
776 registers[reg->index] = node;
779 static void value_def(ir_node *node)
781 const arch_register_t *reg;
784 if (arch_get_irn_reg_class_out(node) != regclass)
787 reg = arch_get_irn_register(node);
788 if (reg == NULL || reg->type & arch_register_type_virtual)
791 reg_node = registers[reg->index];
793 if (reg_node != node) {
794 ir_fprintf(stderr, "Verify warning: Node %+F not registered as value for Register %s (but %+F) in block %+F(%s)\n",
795 node, reg->name, reg_node, get_nodes_block(node), get_irg_dump_name(irg));
798 registers[reg->index] = NULL;
801 static void verify_block_register_allocation(ir_node *block, void *data)
806 nregclasses = arch_env_get_n_reg_class(arch_env);
807 for (i = 0; i < nregclasses; ++i) {
811 regclass = arch_env_get_reg_class(arch_env, i);
813 assert(lv->nodes && "live sets must be computed");
815 n_regs = arch_register_class_n_regs(regclass);
816 registers = ALLOCANZ(ir_node*, n_regs);
818 be_lv_foreach(lv, block, be_lv_state_end, idx) {
819 ir_node *node = be_lv_get_irn(lv, block, idx);
820 value_used(block, node);
823 sched_foreach_reverse(block, node) {
826 if (get_irn_mode(node) == mode_T) {
827 const ir_edge_t *edge;
828 foreach_out_edge(node, edge) {
829 ir_node *def = get_edge_src_irn(edge);
831 check_output_constraints(def);
835 check_output_constraints(node);
838 check_input_constraints(node);
840 /* process uses. (Phi inputs are no real uses) */
842 arity = get_irn_arity(node);
843 for (i2 = 0; i2 < arity; ++i2) {
844 ir_node *use = get_irn_n(node, i2);
845 value_used(block, use);
850 be_lv_foreach(lv, block, be_lv_state_in, idx) {
851 ir_node *node = be_lv_get_irn(lv, block, idx);
855 /* set must be empty now */
856 for (i2 = 0; i2 < n_regs; ++i2) {
857 if (registers[i2] == NULL)
860 ir_fprintf(stderr, "Verify warning: Node %+F not live-in and no def found in block %+F(%s)\n",
861 registers[i2], block, get_irg_dump_name(irg));
867 int be_verify_register_allocation(ir_graph *new_irg)
870 arch_env = be_get_irg_arch_env(irg);
871 lv = be_liveness(irg);
874 be_liveness_assure_sets(lv);
875 irg_block_walk_graph(irg, verify_block_register_allocation, NULL, NULL);
877 be_liveness_free(lv);
879 return !problem_found;