+/*
+ * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
+ *
+ * This file is part of libFirm.
+ *
+ * This file may be distributed and/or modified under the terms of the
+ * GNU General Public License version 2 as published by the Free Software
+ * Foundation and appearing in the file LICENSE.GPL included in the
+ * packaging of this file.
+ *
+ * Licensees holding valid libFirm Professional Edition licenses may use
+ * this file in accordance with the libFirm Commercial License.
+ * Agreement provided with the Software.
+ *
+ * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
+ * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
+ * PURPOSE.
+ */
+
/**
* @file
- * @brief
+ * @brief Backend IRG modification routines.
+ * @author Sebastian Hack, Daniel Grund, Matthias Braun, Christian Wuerdig
+ * @date 04.05.2005
+ *
* This file contains the following IRG modifications for be routines:
- * - backend dominance information
- * - SSA construction for a set of nodes
* - insertion of Perm nodes
* - empty block elimination
* - a simple dead node elimination (set inputs of unreachable nodes to BAD)
- *
- * @author Sebastian Hack, Daniel Grund, Matthias Braun, Christian Wuerdig
- * @date 04.05.2005
- * @version $Id$
- * Copyright: (c) Universitaet Karlsruhe
- * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
*/
-#ifdef HAVE_CONFIG_H
#include "config.h"
-#endif
#include <stdlib.h>
-#ifdef HAVE_MALLOC_H
- #include <malloc.h>
-#endif
-#ifdef HAVE_ALLOCA_H
- #include <alloca.h>
-#endif
-
#include "hashptr.h"
#include "pdeq.h"
#include "pset.h"
#include "util.h"
#include "debug.h"
#include "error.h"
+#include "xmalloc.h"
#include "irflag_t.h"
#include "ircons_t.h"
#include "iredges_t.h"
#include "irgraph_t.h"
#include "irgopt.h"
-#include "irprintf_t.h"
+#include "irgmod.h"
+#include "irprintf.h"
#include "irgwalk.h"
#include "be_t.h"
#include "bechordal_t.h"
#include "bearch.h"
-#include "besched_t.h"
+#include "besched.h"
#include "belive_t.h"
-#include "benode_t.h"
+#include "benode.h"
#include "beutil.h"
#include "beinsn_t.h"
-
+#include "bessaconstr.h"
+#include "beirg.h"
#include "beirgmod.h"
+#include "bemodule.h"
-DEBUG_ONLY(static firm_dbg_module_t *dbgssa = NULL;)
DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
+static int cmp_node_nr(const void *a, const void *b)
+{
+ ir_node **p1 = (ir_node**)a;
+ ir_node **p2 = (ir_node**)b;
+ long n1 = get_irn_node_nr(*p1);
+ long n2 = get_irn_node_nr(*p2);
+ return (n1>n2) - (n1<n2);
+}
+
/*
- ____ ____ _
- / ___/ ___| / \
- \___ \___ \ / _ \
- ___) |__) / ___ \
- |____/____/_/ \_\
- ____ _ _ _
- / ___|___ _ __ ___| |_ _ __ _ _ ___| |_(_) ___ _ __
- | | / _ \| '_ \/ __| __| '__| | | |/ __| __| |/ _ \| '_ \
- | |__| (_) | | | \__ \ |_| | | |_| | (__| |_| | (_) | | | |
- \____\___/|_| |_|___/\__|_| \__,_|\___|\__|_|\___/|_| |_|
+ ___ _ ____
+ |_ _|_ __ ___ ___ _ __| |_ | _ \ ___ _ __ _ __ ___
+ | || '_ \/ __|/ _ \ '__| __| | |_) / _ \ '__| '_ ` _ \
+ | || | | \__ \ __/ | | |_ | __/ __/ | | | | | | |
+ |___|_| |_|___/\___|_| \__| |_| \___|_| |_| |_| |_|
*/
-/* The problem: Given a value and a set of "copies" that are known to represent
- * the same abstract value, rewire all usages of the original value to their
- * closest copy while introducing phis as necessary.
- *
- * Algorithm: Mark all blocks in the iterated dominance frontiers of the value
- * and it's copies. Link the copies ordered by dominance to the blocks.
- * The we search for each use all all definitions in the current block, if none
- * is found, then we search one in the immediate dominator. If we are in a block
- * of the dominance frontier, create a phi and search do the same search for the
- * phi arguments.
- */
-
-/**
- * Calculates the iterated dominance frontier of a set of blocks. Marks the
- * blocks as visited. Sets the link fields of the blocks in the dominance
- * frontier to the block itself.
- */
-static
-void mark_iterated_dominance_frontiers(const be_dom_front_info_t *domfronts,
- waitq *worklist)
+ir_node *insert_Perm_before(ir_graph *irg, const arch_register_class_t *cls,
+ ir_node *pos)
{
- DBG((dbgssa, LEVEL_3, "Dominance Frontier:"));
- while(!pdeq_empty(worklist)) {
- int i;
- ir_node *block = waitq_get(worklist);
- ir_node **domfront = be_get_dominance_frontier(domfronts, block);
- int domfront_len = ARR_LEN(domfront);
-
- for (i = 0; i < domfront_len; ++i) {
- ir_node *y = domfront[i];
- if(Block_block_visited(y))
- continue;
-
- if(!irn_visited(y)) {
- set_irn_link(y, NULL);
- waitq_put(worklist, y);
- }
- DBG((dbgssa, LEVEL_3, " %+F", y));
- mark_Block_block_visited(y);
- }
- }
- DBG((dbgssa, LEVEL_3, "\n"));
-}
-
-typedef struct ssa_constr_env_t {
- ir_node **new_phis; /**< ARR_F of newly created phis or NULL */
- ir_mode *mode; /**< mode of the value */
-} ssa_constr_env_t;
+ be_lv_t *lv = be_get_irg_liveness(irg);
+ ir_nodeset_t live;
-static
-ir_node *search_def_end_of_block(ssa_constr_env_t *env, ir_node *block);
+ ir_node *perm, **nodes;
+ size_t i, n;
-static
-ir_node *create_phi(ssa_constr_env_t *env, ir_node *block, ir_node *link_with)
-{
- int i, n_preds = get_Block_n_cfgpreds(block);
- ir_graph *irg = get_irn_irg(block);
- ir_node *phi;
- ir_node **ins = alloca(n_preds * sizeof(ins[0]));
+ DBG((dbg, LEVEL_1, "Insert Perm before: %+F\n", pos));
- assert(n_preds > 1);
+ ir_nodeset_init(&live);
+ be_liveness_nodes_live_before(lv, cls, pos, &live);
- for(i = 0; i < n_preds; ++i) {
- ins[i] = new_r_Unknown(irg, env->mode);
- }
- phi = new_r_Phi(irg, block, n_preds, ins, env->mode);
- if(env->new_phis != NULL) {
- ARR_APP1(ir_node*, env->new_phis, phi);
+ n = ir_nodeset_size(&live);
+ if (n == 0) {
+ ir_nodeset_destroy(&live);
+ return NULL;
}
- if(env->mode != mode_M) {
- sched_add_after(block, phi);
+ nodes = XMALLOCN(ir_node*, n);
+
+ DBG((dbg, LEVEL_1, "live:\n"));
+ i = 0;
+ foreach_ir_nodeset(&live, irn, iter) {
+ DBG((dbg, LEVEL_1, "\t%+F\n", irn));
+ nodes[i] = irn;
+ i++;
}
+ ir_nodeset_destroy(&live);
+ /* make the input order deterministic */
+ qsort(nodes, n, sizeof(nodes[0]), cmp_node_nr);
- DBG((dbgssa, LEVEL_2, "\tcreating phi %+F in %+F\n", phi, block));
- set_irn_link(link_with, phi);
- mark_irn_visited(block);
+ ir_node *const bl = get_nodes_block(pos);
+ perm = be_new_Perm(cls, bl, n, nodes);
+ sched_add_before(pos, perm);
+ free(nodes);
- for(i = 0; i < n_preds; ++i) {
- ir_node *pred_block = get_Block_cfgpred_block(block, i);
- ir_node *pred_def = search_def_end_of_block(env, pred_block);
+ for (i = 0; i < n; ++i) {
+ ir_node *perm_op = get_irn_n(perm, i);
+ be_ssa_construction_env_t senv;
- set_irn_n(phi, i, pred_def);
+ ir_mode *mode = get_irn_mode(perm_op);
+ ir_node *proj = new_r_Proj(perm, mode, i);
+
+ be_ssa_construction_init(&senv, irg);
+ be_ssa_construction_add_copy(&senv, perm_op);
+ be_ssa_construction_add_copy(&senv, proj);
+ be_ssa_construction_fix_users(&senv, perm_op);
+ be_ssa_construction_update_liveness_phis(&senv, lv);
+ be_liveness_update(lv, perm_op);
+ be_liveness_update(lv, proj);
+ be_ssa_construction_destroy(&senv);
}
- return phi;
-}
-
-static
-ir_node *get_def_at_idom(ssa_constr_env_t *env, ir_node *block)
-{
- ir_node *dom = get_Block_idom(block);
- ir_node *def = search_def_end_of_block(env, dom);
-
- return def;
+ return perm;
}
-static
-ir_node *search_def_end_of_block(ssa_constr_env_t *env, ir_node *block)
-{
- if(irn_visited(block)) {
- assert(get_irn_link(block) != NULL);
- return get_irn_link(block);
- } else if(Block_block_visited(block)) {
- return create_phi(env, block, block);
- } else {
- ir_node *def = get_def_at_idom(env, block);
-#if 1
- mark_irn_visited(block);
- set_irn_link(block, def);
-#endif
-
- return def;
- }
-}
+static int blocks_removed;
-static
-ir_node *search_def(ssa_constr_env_t *env, ir_node *at)
+/**
+ * Post-block-walker: Find blocks containing only one jump and
+ * remove them.
+ */
+static void remove_empty_block(ir_node *block)
{
- ir_node *block = get_nodes_block(at);
- ir_node *node;
- ir_node *def;
-
- DBG((dbgssa, LEVEL_3, "\t...searching def at %+F\n", at));
+ int i;
+ int arity;
+ ir_node *pred;
+ ir_node *succ_block;
+ ir_node *jump = NULL;
+ ir_graph *irg = get_irn_irg(block);
+ ir_entity *entity;
+
+ if (irn_visited_else_mark(block))
+ return;
- /* no defs in the current block we can do the normal searching */
- if(!irn_visited(block) && !Block_block_visited(block)) {
- DBG((dbgssa, LEVEL_3, "\t...continue at idom\n"));
- return get_def_at_idom(env, block);
- }
+ if (get_Block_n_cfgpreds(block) != 1)
+ goto check_preds;
- /* there are defs in the current block, walk the linked list to find
- the one immediately dominating us
- */
- node = block;
- def = get_irn_link(node);
- while(def != NULL) {
-#if 0
- assert(get_nodes_block(def) == block);
- if(!value_dominates_intrablock(at, def)) {
- DBG((dbgssa, LEVEL_3, "\t...found dominating def %+F\n", def));
- return def;
- }
-#else
- if(!value_dominates(at, def)) {
- DBG((dbgssa, LEVEL_3, "\t...found dominating def %+F\n", def));
- return def;
+ sched_foreach(block, node) {
+ if (! is_Jmp(node)
+ && !(arch_get_irn_flags(node) & arch_irn_flags_simple_jump))
+ goto check_preds;
+ if (jump != NULL) {
+ /* we should never have 2 jumps in a block */
+ panic("found 2 jumps in a block");
}
-#endif
- node = def;
- def = get_irn_link(node);
- }
-
- /* block in dominance frontier? create a phi then */
- if(Block_block_visited(block)) {
- DBG((dbgssa, LEVEL_3, "\t...create phi at block %+F\n", block));
- assert(!is_Phi(node));
- return create_phi(env, block, node);
+ jump = node;
}
-
- DBG((dbgssa, LEVEL_3, "\t...continue at idom (after checking block)\n"));
- return get_def_at_idom(env, block);
-}
-
-/**
- * Adds a definition into the link field of the block. The definitions are
- * sorted by dominance. A non-visited block means no definition has been
- * inserted yet.
- */
-static
-void introduce_def_at_block(ir_node *block, ir_node *def)
-{
- if(irn_visited(block)) {
- ir_node *node = block;
- ir_node *current_def;
-
- while(1) {
- current_def = get_irn_link(node);
- if(current_def == def) {
- /* already in block */
- return;
- }
- if(current_def == NULL)
- break;
- if(value_dominates(current_def, def))
- break;
- node = current_def;
+ if (jump == NULL)
+ goto check_preds;
+
+ entity = get_Block_entity(block);
+ pred = get_Block_cfgpred(block, 0);
+ succ_block = NULL;
+ foreach_out_edge_safe(jump, edge) {
+ int pos = get_edge_src_pos(edge);
+
+ assert(succ_block == NULL);
+ succ_block = get_edge_src_irn(edge);
+ if (get_Block_entity(succ_block) != NULL && entity != NULL) {
+ /*
+ * Currently we can add only one label for a block.
+ * Therefore we cannot combine them if both block already have one.
+ */
+ goto check_preds;
}
- set_irn_link(node, def);
- set_irn_link(def, current_def);
- } else {
- set_irn_link(block, def);
- set_irn_link(def, NULL);
- mark_irn_visited(block);
+ set_irn_n(succ_block, pos, pred);
}
-}
-ir_node **be_ssa_construction(const be_dom_front_info_t *domfronts, be_lv_t *lv,
- ir_node *value, int copies_len, ir_node **copies,
- const ir_nodeset_t *ignore_uses, int need_new_phis)
-{
- ir_graph *irg = get_irn_irg(value);
- const ir_edge_t *edge, *next;
- int i;
- ir_node *block;
- waitq *worklist;
- ssa_constr_env_t env;
-
- /* We need to collect the phi functions to compute their liveness. */
- if(lv != NULL || need_new_phis) {
- env.new_phis = NEW_ARR_F(ir_node*, 0);
- } else {
- env.new_phis = NULL;
+ if (entity != NULL) {
+ /* move the label to the successor block */
+ set_Block_entity(succ_block, entity);
}
- env.mode = get_irn_mode(value);
- set_using_visited(irg);
- set_using_block_visited(irg);
- set_using_irn_link(irg);
+ /* there can be some non-scheduled Pin nodes left in the block, move them
+ * to the succ block (Pin) or pred block (Sync) */
+ foreach_out_edge_safe(block, edge) {
+ ir_node *const node = get_edge_src_irn(edge);
- /* we use the visited flag to indicate blocks in the dominance frontier
- * and blocks that already have the relevant value at the end calculated */
- inc_irg_visited(irg);
- /* We use the block visited flag to indicate blocks in the dominance
- * froniter of some values (and this potentially needing phis) */
- inc_irg_block_visited(irg);
-
- DBG((dbgssa, LEVEL_1, "Introducing following copies for: %+F\n", value));
- /* compute iterated dominance frontiers and create lists in the block link
- * fields that sort usages by dominance. Blocks in the dominance frontier
- * are marked by links back to the block. */
- worklist = new_waitq();
-
- block = get_nodes_block(value);
- introduce_def_at_block(block, value);
- waitq_put(worklist, block);
-
- for(i = 0; i < copies_len; ++i) {
- ir_node *copy = copies[i];
- block = get_nodes_block(copy);
-
- if(!irn_visited(block)) {
- waitq_put(worklist, block);
+ if (node == jump)
+ continue;
+ /* we simply kill Pins, because there are some strange interactions
+ * between jump threading, which produce PhiMs with Pins, we simply
+ * kill the pins here, everything is scheduled anyway */
+ if (is_Pin(node)) {
+ exchange(node, get_Pin_op(node));
+ continue;
}
- introduce_def_at_block(block, copy);
- DBG((dbgssa, LEVEL_1, "\t%+F in %+F\n", copy, block));
- }
-
- mark_iterated_dominance_frontiers(domfronts, worklist);
- del_waitq(worklist);
-
- DBG((dbgssa, LEVEL_2, "New Definitions:\n"));
- /*
- * Search the valid def for each use and set it.
- */
- foreach_out_edge_safe(value, edge, next) {
- ir_node *use = get_edge_src_irn(edge);
- ir_node *at = use;
- ir_node *def;
- int pos = get_edge_src_pos(edge);
-
- if(ignore_uses != NULL && ir_nodeset_contains(ignore_uses, use))
+ if (is_Sync(node)) {
+ set_nodes_block(node, get_nodes_block(pred));
continue;
-
- if(is_Phi(use)) {
- ir_node *block = get_nodes_block(use);
- ir_node *predblock = get_Block_cfgpred_block(block, pos);
- at = sched_last(predblock);
}
-
- def = search_def(&env, at);
-
- if(def == NULL) {
- panic("no definition found for %+F at position %d\n", use, pos);
+ if (is_End(node)) { /* End-keep, reroute it to the successor */
+ int pos = get_edge_src_pos(edge);
+ set_irn_n(node, pos, succ_block);
+ continue;
}
-
- DBG((dbgssa, LEVEL_2, "\t%+F(%d) -> %+F\n", use, pos, def));
- set_irn_n(use, pos, def);
+ panic("Unexpected node %+F in block %+F with empty schedule", node, block);
}
- /* Recompute the liveness of the original nodes, the copies and the
- * inserted phis. */
- if(lv != NULL) {
- int n;
-
- be_liveness_update(lv, value);
- for(i = 0; i < copies_len; ++i) {
- ir_node *copy = copies[i];
- be_liveness_update(lv, copy);
- }
-
- n = ARR_LEN(env.new_phis);
- for(i = 0; i < n; ++i) {
- ir_node *phi = env.new_phis[i];
- be_liveness_introduce(lv, phi);
- }
- }
+ set_Block_cfgpred(block, 0, new_r_Bad(irg, mode_X));
+ kill_node(jump);
+ blocks_removed = 1;
- clear_using_visited(irg);
- clear_using_block_visited(irg);
- clear_using_irn_link(irg);
+ /* check predecessor */
+ remove_empty_block(get_nodes_block(pred));
+ return;
- if(!need_new_phis && env.new_phis != NULL) {
- DEL_ARR_F(env.new_phis);
- return NULL;
+check_preds:
+ arity = get_Block_n_cfgpreds(block);
+ for (i = 0; i < arity; ++i) {
+ ir_node *pred = get_Block_cfgpred_block(block, i);
+ remove_empty_block(pred);
}
- return env.new_phis;
}
-void be_ssa_constr_set_ignore(const be_dom_front_info_t *domfronts, be_lv_t *lv,
- pset *nodes, pset *ignores)
+/* removes basic blocks that just contain a jump instruction */
+int be_remove_empty_blocks(ir_graph *irg)
{
- ir_graph *irg;
- const ir_edge_t *edge, *next;
- int i;
- ir_node *block;
- waitq *worklist;
- ir_node *value;
- ssa_constr_env_t env;
-
- foreach_pset(nodes, value) {
- pset_break(nodes);
- break;
- }
- irg = get_irn_irg(value);
-
- /* We need to collect the phi functions to compute their liveness. */
- if(lv != NULL) {
- env.new_phis = NEW_ARR_F(ir_node*, 0);
- }
+ ir_node *end;
+ int i, arity;
- set_using_visited(irg);
- set_using_block_visited(irg);
- set_using_irn_link(irg);
+ blocks_removed = 0;
- /* we use the visited flag to indicate blocks in the dominance frontier
- * and blocks that already have the relevant value at the end calculated */
+ ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
inc_irg_visited(irg);
- /* We use the block visited flag to indicate blocks in the dominance
- * froniter of some values (and this potentially needing phis) */
- inc_irg_block_visited(irg);
-
- DBG((dbgssa, LEVEL_1, "Introducing following copies for:\n"));
-
- /* compute iterated dominance frontiers and create lists in the block link
- * fields that sort usages by dominance. Blocks in the dominance frontier
- * are marked by links back to the block. */
- worklist = new_waitq();
-
- foreach_pset(nodes, value) {
- block = get_nodes_block(value);
- env.mode = get_irn_mode(value);
-
- if(!irn_visited(block)) {
- waitq_put(worklist, block);
- }
- introduce_def_at_block(block, value);
- DBG((dbgssa, LEVEL_1, "\t%+F in %+F\n", value, block));
- }
-
- mark_iterated_dominance_frontiers(domfronts, worklist);
- del_waitq(worklist);
-
- /*
- * Search the valid def for each use and set it.
- */
- foreach_pset(nodes, value) {
- foreach_out_edge_safe(value, edge, next) {
- ir_node *use = get_edge_src_irn(edge);
- ir_node *at = use;
- ir_node *def;
- int pos = get_edge_src_pos(edge);
-
- if(ignores != NULL && pset_find_ptr(ignores, use))
- continue;
-
- if(is_Phi(use)) {
- ir_node *block = get_nodes_block(use);
- ir_node *predblock = get_Block_cfgpred_block(block, pos);
- at = sched_last(predblock);
- }
-
- def = search_def(&env, at);
-
- if(def == NULL) {
- panic("no definition found for %+F input %d\n", use, pos);
- }
-
- DBG((dbgssa, LEVEL_2, "\t%+F(%d) -> %+F\n", use, pos, def));
- set_irn_n(use, pos, def);
- }
+ remove_empty_block(get_irg_end_block(irg));
+ end = get_irg_end(irg);
+ arity = get_irn_arity(end);
+ for (i = 0; i < arity; ++i) {
+ ir_node *pred = get_irn_n(end, i);
+ if (!is_Block(pred))
+ continue;
+ remove_empty_block(pred);
}
+ ir_free_resources(irg, IR_RESOURCE_IRN_VISITED);
- /* Recompute the liveness of the original nodes, the copies and the
- * inserted phis. */
- if(lv != NULL) {
- int n;
-
- foreach_pset(nodes, value) {
- be_liveness_update(lv, value);
- }
-
- n = ARR_LEN(env.new_phis);
- for(i = 0; i < n; ++i) {
- ir_node *phi = env.new_phis[i];
- be_liveness_introduce(lv, phi);
- }
- DEL_ARR_F(env.new_phis);
+ if (blocks_removed) {
+ /* invalidate analysis info */
+ clear_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_DOMINANCE);
}
-
- clear_using_visited(irg);
- clear_using_block_visited(irg);
- clear_using_irn_link(irg);
+ return blocks_removed;
}
-/*
- ___ _ ____
- |_ _|_ __ ___ ___ _ __| |_ | _ \ ___ _ __ _ __ ___
- | || '_ \/ __|/ _ \ '__| __| | |_) / _ \ '__| '_ ` _ \
- | || | | \__ \ __/ | | |_ | __/ __/ | | | | | | |
- |___|_| |_|___/\___|_| \__| |_| \___|_| |_| |_| |_|
+//---------------------------------------------------------------------------
-*/
+typedef struct remove_dead_nodes_env_t_ {
+ bitset_t *reachable;
+ ir_graph *irg;
+ be_lv_t *lv;
+} remove_dead_nodes_env_t;
-ir_node *insert_Perm_after(const arch_env_t *arch_env,
- be_lv_t *lv,
- const arch_register_class_t *cls,
- be_dom_front_info_t *dom_front,
- ir_node *pos)
+/**
+ * Post-walker: remember all visited nodes in a bitset.
+ */
+static void mark_dead_nodes_walker(ir_node *node, void *data)
{
- ir_node *bl = is_Block(pos) ? pos : get_nodes_block(pos);
- ir_graph *irg = get_irn_irg(bl);
- pset *live = pset_new_ptr_default();
-
- ir_node *curr, *irn, *perm, **nodes;
- int i, n;
-
- DBG((dbg, LEVEL_1, "Insert Perm after: %+F\n", pos));
-
- be_liveness_nodes_live_at(lv, arch_env, cls, pos, live);
-
- n = pset_count(live);
-
- if(n == 0) {
- del_pset(live);
- return NULL;
- }
-
- nodes = xmalloc(n * sizeof(nodes[0]));
-
- DBG((dbg, LEVEL_1, "live:\n"));
- for(irn = pset_first(live), i = 0; irn; irn = pset_next(live), i++) {
- DBG((dbg, LEVEL_1, "\t%+F\n", irn));
- nodes[i] = irn;
- }
- del_pset(live);
-
- perm = be_new_Perm(cls, irg, bl, n, nodes);
- sched_add_after(pos, perm);
- free(nodes);
-
- curr = perm;
- for (i = 0; i < n; ++i) {
- ir_node *copies[1];
- ir_node *perm_op = get_irn_n(perm, i);
- const arch_register_t *reg = arch_get_irn_register(arch_env, perm_op);
-
- ir_mode *mode = get_irn_mode(perm_op);
- ir_node *proj = new_r_Proj(irg, bl, perm, mode, i);
- arch_set_irn_register(arch_env, proj, reg);
-
- sched_add_after(curr, proj);
- curr = proj;
-
- copies[0] = proj;
-
- be_ssa_construction(dom_front, lv, perm_op, 1, copies, NULL, 0);
- }
-
- return perm;
+ remove_dead_nodes_env_t *env = (remove_dead_nodes_env_t*) data;
+ bitset_set(env->reachable, get_irn_idx(node));
}
/**
- * Post-block-walker: Find blocks containing only one jump and
- * remove them.
+ * Post-block-walker:
+ * Walk through the schedule of every block and remove all dead nodes from it.
*/
-static void remove_empty_block(ir_node *block, void *data) {
- const ir_edge_t *edge, *next;
- ir_node *node;
- int *changed = data;
- ir_node *jump = NULL;
+static void remove_dead_nodes_walker(ir_node *block, void *data)
+{
+ remove_dead_nodes_env_t *env = (remove_dead_nodes_env_t*) data;
+ ir_node *node, *next;
- assert(is_Block(block));
+ for (node = sched_first(block); ! sched_is_end(node); node = next) {
+ /* get next node now, as after calling sched_remove it will be invalid */
+ next = sched_next(node);
- if (get_Block_n_cfgpreds(block) != 1)
- return;
+ if (bitset_is_set(env->reachable, get_irn_idx(node)))
+ continue;
- sched_foreach(block, node) {
- if (! is_Jmp(node))
- return;
- if (jump != NULL) {
- /* we should never have 2 jumps in a block */
- panic("We should never have 2 jumps in a block");
+ if (env->lv != NULL)
+ be_liveness_remove(env->lv, node);
+ sched_remove(node);
+
+ /* kill projs */
+ if (get_irn_mode(node) == mode_T) {
+ foreach_out_edge_safe(node, edge) {
+ ir_node *proj = get_edge_src_irn(edge);
+ if (!is_Proj(proj))
+ continue;
+ if (env->lv != NULL)
+ be_liveness_remove(env->lv, proj);
+ kill_node(proj);
+ }
}
- jump = node;
- }
-
- if (jump == NULL)
- return;
-
- node = get_Block_cfgpred(block, 0);
- foreach_out_edge_safe(jump, edge, next) {
- ir_node *block = get_edge_src_irn(edge);
- int pos = get_edge_src_pos(edge);
-
- set_irn_n(block, pos, node);
+ kill_node(node);
}
-
- set_Block_cfgpred(block, 0, new_Bad());
- be_kill_node(jump);
- *changed = 1;
}
-/* removes basic blocks that just contain a jump instruction */
-int be_remove_empty_blocks(ir_graph *irg) {
- int changed = 0;
+void be_remove_dead_nodes_from_schedule(ir_graph *irg)
+{
+ remove_dead_nodes_env_t env;
+ env.reachable = bitset_alloca(get_irg_last_idx(irg));
+ env.lv = be_get_irg_liveness(irg);
+ env.irg = irg;
- irg_block_walk_graph(irg, remove_empty_block, NULL, &changed);
- if (changed) {
- /* invalidate analysis info */
- set_irg_doms_inconsistent(irg);
- set_irg_extblk_inconsistent(irg);
- set_irg_outs_inconsistent(irg);
- }
- return changed;
+ // mark all reachable nodes
+ irg_walk_graph(irg, mark_dead_nodes_walker, NULL, &env);
+
+ // walk schedule and remove non-marked nodes
+ irg_block_walk_graph(irg, remove_dead_nodes_walker, NULL, &env);
}
+BE_REGISTER_MODULE_CONSTRUCTOR(be_init_irgmod)
void be_init_irgmod(void)
{
- FIRM_DBG_REGISTER(dbgssa, "firm.be.ssaconstr");
FIRM_DBG_REGISTER(dbg, "firm.be.irgmod");
}
-
-BE_REGISTER_MODULE_CONSTRUCTOR(be_init_irgmod);
projects / libfirm / blobdiff