+/*
+ * 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 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
- * Copyright: (c) Universitaet Karlsruhe
- * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
- * CVS-Id: $Id$
*/
-#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 "pmap.h"
#include "util.h"
#include "debug.h"
+#include "error.h"
+#include "xmalloc.h"
#include "irflag_t.h"
#include "ircons_t.h"
#include "irmode_t.h"
#include "irdom_t.h"
#include "iredges_t.h"
+#include "irgraph_t.h"
#include "irgopt.h"
+#include "irgmod.h"
#include "irprintf_t.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"
-#define DBG_MODULE "firm.be.irgmod"
-#define DBG_LEVEL SET_LEVEL_0
-
-/*
- ____ _
- | _ \ ___ _ __ ___ (_)_ __ __ _ _ __ ___ ___
- | | | |/ _ \| '_ ` _ \| | '_ \ / _` | '_ \ / __/ _ \
- | |_| | (_) | | | | | | | | | | (_| | | | | (_| __/
- |____/ \___/|_| |_| |_|_|_| |_|\__,_|_| |_|\___\___|
- | ___| __ ___ _ __ | |_(_) ___ _ __ ___
- | |_ | '__/ _ \| '_ \| __| |/ _ \ '__/ __|
- | _|| | | (_) | | | | |_| | __/ | \__ \
- |_| |_| \___/|_| |_|\__|_|\___|_| |___/
-
-*/
-
-/**
- * The dominance frontier for a graph.
- */
-struct _be_dom_front_info_t {
- pmap *df_map; /**< A map, mapping every block to a list of its dominance frontier blocks. */
- struct obstack obst; /**< An obstack holding all the frontier data. */
-};
-
-/**
- * A wrapper for get_Block_idom.
- * This function returns the block itself, if the block is the start
- * block. Returning NULL would make any != comparison true which
- * suggests, that the start block is dominated by some other node.
- * @param bl The block.
- * @return The immediate dominator of the block.
- */
-static INLINE ir_node *get_idom(ir_node *bl)
-{
- ir_node *idom = get_Block_idom(bl);
- return idom == NULL ? bl : idom;
-}
-
-/**
- * Compute the dominance frontier for a given block.
- *
- * @param blk the block where the calculation starts
- *
- * @return the list of all blocks in the dominance frontier of blk
- */
-static ir_node **compute_df(ir_node *blk, be_dom_front_info_t *info)
-{
- ir_node *c;
- const ir_edge_t *edge;
- ir_node **df_list = NEW_ARR_F(ir_node *, 0);
- ir_node **df;
- int len;
-
- /* Add local dominance frontiers */
- foreach_block_succ(blk, edge) {
- ir_node *y = edge->src;
-
- if (get_idom(y) != blk) {
- ARR_APP1(ir_node *, df_list, y);
- }
- }
-
- /*
- * Go recursively down the dominance tree and add all blocks
- * into the dominance frontiers of the children, which are not
- * dominated by the given block.
- */
- for (c = get_Block_dominated_first(blk); c; c = get_Block_dominated_next(c)) {
- int i;
- ir_node **df_c_list = compute_df(c, info);
-
- for (i = ARR_LEN(df_c_list) - 1; i >= 0; --i) {
- ir_node *w = df_c_list[i];
- if (get_idom(w) != blk)
- ARR_APP1(ir_node *, df_list, w);
- }
- }
-
- /* now copy the flexible array to the obstack */
- len = ARR_LEN(df_list);
- df = NEW_ARR_D(ir_node *, &info->obst, len);
- memcpy(df, df_list, len * sizeof(df[0]));
- DEL_ARR_F(df_list);
-
- pmap_insert(info->df_map, blk, df);
- return df;
-}
-
-be_dom_front_info_t *be_compute_dominance_frontiers(ir_graph *irg)
-{
- be_dom_front_info_t *info = xmalloc(sizeof(*info));
-
- edges_assure(irg);
- obstack_init(&info->obst);
- info->df_map = pmap_create();
- assure_doms(irg);
- (void)compute_df(get_irg_start_block(irg), info);
-
- return info;
-}
-
-void be_free_dominance_frontiers(be_dom_front_info_t *info)
-{
- obstack_free(&info->obst, NULL);
- pmap_destroy(info->df_map);
- free(info);
-}
-
-/* Get the dominance frontier of a block. */
-ir_node **be_get_dominance_frontier(be_dom_front_info_t *info, ir_node *block)
-{
- return pmap_get(info->df_map, block);
-}
-
-static void determine_phi_blocks(pset *copies, pset *copy_blocks, pset *phi_blocks, be_dom_front_info_t *df_info)
-{
- ir_node *bl;
- waitq *worklist = new_waitq();
- FIRM_DBG_REGISTER(firm_dbg_module_t *dbg, DBG_MODULE);
-
- /*
- * Fill the worklist queue and the rest of the orig blocks array.
- */
- for (bl = pset_first(copy_blocks); bl; bl = pset_next(copy_blocks)) {
- waitq_put(worklist, bl);
- }
-
- while (!pdeq_empty(worklist)) {
- ir_node *bl = waitq_get(worklist);
- ir_node **df = be_get_dominance_frontier(df_info, bl);
- int i;
-
- ir_node *y;
-
- DBG((dbg, LEVEL_3, "dom front of %+F\n", bl));
- DEBUG_ONLY(
- for (i = ARR_LEN(df) - 1; i >= 0; --i)
- DBG((dbg, LEVEL_3, "\t%+F\n", df[i]))
- );
-
- for (i = ARR_LEN(df) - 1; i >= 0; --i) {
- y = df[i];
- if (!pset_find_ptr(phi_blocks, y)) {
- pset_insert_ptr(phi_blocks, y);
-
- /*
- * Clear the link field of a possible phi block, since
- * the possibly created phi will be stored there. See,
- * search_def()
- */
- set_irn_link(y, NULL);
-
- if(!pset_find_ptr(copy_blocks, y))
- waitq_put(worklist, y);
- }
- }
- }
-
- del_waitq(worklist);
-}
-
-/*
- ____ ____ _
- / ___/ ___| / \
- \___ \___ \ / _ \
- ___) |__) / ___ \
- |____/____/_/ \_\
- ____ _ _ _
- / ___|___ _ __ ___| |_ _ __ _ _ ___| |_(_) ___ _ __
- | | / _ \| '_ \/ __| __| '__| | | |/ __| __| |/ _ \| '_ \
- | |__| (_) | | | \__ \ |_| | | |_| | (__| |_| | (_) | | | |
- \____\___/|_| |_|___/\__|_| \__,_|\___|\__|_|\___/|_| |_|
-
-*/
-
-/**
- * Find the copy of the given original node whose value is 'active'
- * at a usage.
- *
- * The usage is given as a node and a position. Initially, the given operand
- * points to a node for which copies were introduced. We have to find
- * the valid copy for this usage. This is done by traversing the
- * dominance tree upwards. If the usage is a phi function, we start
- * traversing from the predecessor block which corresponds to the phi
- * usage.
- *
- * @param usage The node which uses the original node.
- * @param pos The position of the argument which corresponds to the original node.
- * @param copies A set containing all node which are copies from the original node.
- * @param copy_blocks A set containing all basic block in which copies of the original node are located.
- * @param phis A set where all created phis are recorded.
- * @param phi_blocks A set of all blocks where Phis shall be inserted (iterated dominance frontier).
- * @param mode The mode for the Phi if one has to be created.
- * @return The valid copy for usage.
- */
-static ir_node *search_def(ir_node *usage, int pos, pset *copies, pset *copy_blocks, pset *phis, pset *phi_blocks, ir_mode *mode)
-{
- ir_node *curr_bl;
- ir_node *start_irn;
- FIRM_DBG_REGISTER(firm_dbg_module_t *dbg, DBG_MODULE);
-
- curr_bl = get_nodes_block(usage);
-
- DBG((dbg, LEVEL_1, "Searching valid def for use %+F at pos %d\n", usage, pos));
- /*
- * If the usage is in a phi node, search the copy in the
- * predecessor denoted by pos.
- */
- if(is_Phi(usage)) {
- curr_bl = get_Block_cfgpred_block(curr_bl, pos);
- start_irn = sched_last(curr_bl);
- } else {
- start_irn = sched_prev(usage);
- }
-
- /*
- * Traverse the dominance tree upwards from the
- * predecessor block of the usage.
- */
- while(curr_bl != NULL) {
- ir_node *phim;
-
- /*
- * If this block contains a copy, search the block
- * instruction by instruction. If nothing is found
- * search for a not scheduled PhiM.
- */
- if(pset_find_ptr(copy_blocks, curr_bl)) {
- ir_node *irn;
-
- /* Look at each instruction from last to first. */
- sched_foreach_reverse_from(start_irn, irn) {
-
- /* Take the first copy we find. */
- if(pset_find_ptr(copies, irn))
- return irn;
- }
-
- for(phim = pset_first(copies); phim; phim = pset_next(copies)) {
- if(!is_Phi(phim) || !(get_irn_mode(phim) == mode_M))
- continue;
-
- if(get_nodes_block(phim) == curr_bl) {
- pset_break(copies);
- return phim;
- }
- }
- }
-
- if(pset_find_ptr(phi_blocks, curr_bl)) {
- ir_node *phi = get_irn_link(curr_bl);
-
- if(phi == NULL) {
- int i, n_preds = get_irn_arity(curr_bl);
- ir_graph *irg = get_irn_irg(curr_bl);
- ir_node **ins = alloca(n_preds * sizeof(ins[0]));
-
- for(i = 0; i < n_preds; ++i)
- ins[i] = new_r_Bad(irg);
-
- phi = new_r_Phi(irg, curr_bl, n_preds, ins, mode);
- DBG((dbg, LEVEL_2, "\tcreating phi %+F in %+F\n", phi, curr_bl));
-
- set_irn_link(curr_bl, phi);
- if(mode != mode_M)
- sched_add_after(curr_bl, phi);
-
- for(i = 0; i < n_preds; ++i) {
- ir_node *arg = search_def(phi, i, copies, copy_blocks, phis, phi_blocks, mode);
- if(arg == NULL) {
- ir_node *irn;
-
- ir_fprintf(stderr, "no definition found for %+F at position %d\nCopies: ", phi, i);
- for(irn = pset_first(copies); irn; irn = pset_next(copies)) {
- ir_fprintf(stderr, "%+F ", irn);
- }
- ir_fprintf(stderr, "\n\n");
- assert(arg && "no definition found");
- }
- DBG((dbg, LEVEL_2, "\t\t%+F(%d) -> %+F\n", phi, i, arg));
- set_irn_n(phi, i, arg);
- }
-
- if(phis != NULL)
- pset_insert_ptr(phis, phi);
- }
-
- return phi;
- }
-
- /* If were not done yet, look in the immediate dominator */
- curr_bl = get_Block_idom(curr_bl);
- if(curr_bl)
- start_irn = sched_last(curr_bl);
- }
-
- return NULL;
-}
-
-static void fix_usages(pset *copies, pset *copy_blocks, pset *phi_blocks, pset *phis, pset *ignore_uses)
-{
- int n_outs = 0;
- struct obstack obst;
- ir_node *irn;
- int i;
- struct out {
- ir_node *irn;
- int pos;
- } *outs;
-
- FIRM_DBG_REGISTER(firm_dbg_module_t *dbg, DBG_MODULE);
-
- obstack_init(&obst);
-
- /*
- * Put all outs into an array.
- * This is necessary, since the outs would be modified while
- * iterating on them what could bring the outs module in trouble.
- */
- for (irn = pset_first(copies); irn; irn = pset_next(copies)) {
- const ir_edge_t *edge;
- foreach_out_edge(irn, edge) {
- ir_node *src = get_edge_src_irn(edge);
- /* ignore all users from ignore_uses or keep-alives (user is End node) */
- if (! pset_find_ptr(ignore_uses, src) && ! is_End(src)) {
- struct out tmp;
- tmp.irn = src;
- tmp.pos = get_edge_src_pos(edge);
- obstack_grow(&obst, &tmp, sizeof(tmp));
- n_outs++;
- }
- }
- }
- outs = obstack_finish(&obst);
-
- /*
- * Search the valid def for each out and set it.
- */
- for(i = 0; i < n_outs; ++i) {
- ir_node *irn = outs[i].irn;
- int pos = outs[i].pos;
- ir_mode *mode = get_irn_mode(get_irn_n(irn, pos));
-
- ir_node *def;
-
- def = search_def(irn, pos, copies, copy_blocks, phis, phi_blocks, mode);
- DBG((dbg, LEVEL_2, "\t%+F(%d) -> %+F\n", irn, pos, def));
-
- if(def == NULL) {
- ir_fprintf(stderr, "no definition found for %+F at position %d\nCopies: ", irn, pos);
- for(irn = pset_first(copies); irn; irn = pset_next(copies)) {
- ir_fprintf(stderr, "%+F ", irn);
- }
- ir_fprintf(stderr, "\n\n");
- assert(def && "no definition found");
- }
- set_irn_n(irn, pos, def);
- }
-
- obstack_free(&obst, NULL);
-}
-
-#if 0
-/**
- * Remove phis which are not necessary.
- * During place_phi_functions() phi functions are put on the dominance
- * frontiers blindly. However some of them will never be used (these
- * have at least one predecessor which is NULL, see search_def() for
- * this case). Since place_phi_functions() enters them into the
- * schedule, we have to remove them from there.
- *
- * @param copies The set of all copies made (including the phi functions).
- */
-static void remove_odd_phis(pset *copies, pset *unused_copies)
-{
- ir_node *irn;
-
- for(irn = pset_first(copies); irn; irn = pset_next(copies)) {
- if(is_Phi(irn)) {
- int i, n;
- int illegal = 0;
-
- assert(sched_is_scheduled(irn) && "phi must be scheduled");
- for(i = 0, n = get_irn_arity(irn); i < n && !illegal; ++i)
- illegal = get_irn_n(irn, i) == NULL;
-
- if(illegal) {
- for(i = 0, n = get_irn_arity(irn); i < n; ++i)
- set_irn_n(irn, i, new_Bad());
- sched_remove(irn);
- }
- }
- }
-
- for(irn = pset_first(unused_copies); irn; irn = pset_next(unused_copies)) {
- for(i = 0, n = get_irn_arity(irn); i < n; ++i)
- set_irn_n(irn, i, new_Bad());
- sched_remove(irn);
- }
-}
-#endif /* if 0 */
-
-void be_ssa_constr_phis_ignore(be_dom_front_info_t *info, be_lv_t *lv, int n, ir_node *nodes[], pset *phis, pset *ignore_uses)
-{
- pset *irns = pset_new_ptr(n);
- int i;
-
- for(i = 0; i < n; ++i)
- pset_insert_ptr(irns, nodes[i]);
- be_ssa_constr_set_phis_ignore(info, lv, irns, phis, ignore_uses);
- del_pset(irns);
-}
-
-void be_ssa_constr_ignore(be_dom_front_info_t *info, be_lv_t *lv, int n, ir_node *nodes[], pset *ignore_uses)
-{
- be_ssa_constr_phis_ignore(info, lv, n, nodes, NULL, ignore_uses);
-}
-
-void be_ssa_constr(be_dom_front_info_t *info, be_lv_t *lv, int n, ir_node *nodes[])
-{
- pset *empty_set = be_empty_set();
- be_ssa_constr_ignore(info, lv, n, nodes, empty_set);
-}
-
-void be_ssa_constr_set_phis_ignore(be_dom_front_info_t *df, be_lv_t *lv, pset *nodes, pset *phis, pset *ignore_uses)
-{
- int n = pset_count(nodes);
- pset *blocks = pset_new_ptr(n);
- pset *phi_blocks = pset_new_ptr(n);
- int save_optimize = get_optimize();
- int save_normalize = get_opt_normalize();
- int phis_set_created = 0;
- FIRM_DBG_REGISTER(firm_dbg_module_t *dbg, DBG_MODULE);
-
- ir_node *irn;
-
- /* We need to collect the phi functions to compute their liveness. */
- if(lv && !phis) {
- phis_set_created = 1;
- phis = pset_new_ptr_default();
- }
-
- DBG((dbg, LEVEL_1, "Introducing following copies for:\n"));
-
- /* Fill the sets. */
- for(irn = pset_first(nodes); irn; irn = pset_next(nodes)) {
- ir_node *bl = get_nodes_block(irn);
- pset_insert_ptr(blocks, bl);
- DBG((dbg, LEVEL_1, "\t%+F in %+F\n", irn, bl));
- }
-
- /*
- * Disable optimization so that the phi functions do not
- * disappear.
- */
- set_optimize(0);
- set_opt_normalize(0);
-
- /*
- * Place the phi functions and reroute the usages.
- */
- determine_phi_blocks(nodes, blocks, phi_blocks, df);
- fix_usages(nodes, blocks, phi_blocks, phis, ignore_uses);
-
- /* reset the optimizations */
- set_optimize(save_optimize);
- set_opt_normalize(save_normalize);
-
- del_pset(phi_blocks);
- del_pset(blocks);
-
- /* Recompute the liveness (if wanted) of the original nodes, the copies and the inserted phis. */
- if(lv) {
-#if 1
- foreach_pset(nodes, irn)
- be_liveness_update(lv, irn);
-
- foreach_pset(phis, irn)
- be_liveness_introduce(lv, irn);
-#else
- be_liveness_recompute(lv);
-#endif
- }
-
- /* Free the phi set of we created it. */
- if(phis_set_created)
- del_pset(phis);
-
-}
-
-void be_ssa_constr_set_phis(be_dom_front_info_t *df, be_lv_t *lv, pset *nodes, pset *phis)
-{
- pset *empty_set = be_empty_set();
- be_ssa_constr_set_phis_ignore(df, lv, nodes, phis, empty_set);
-}
-
-void be_ssa_constr_set_ignore(be_dom_front_info_t *df, be_lv_t *lv, pset *nodes, pset *ignore_uses)
-{
- be_ssa_constr_set_phis_ignore(df, lv, nodes, NULL, ignore_uses);
-}
-
-void be_ssa_constr_set(be_dom_front_info_t *info, be_lv_t *lv, pset *nodes)
-{
- pset *empty_set = be_empty_set();
- be_ssa_constr_set_ignore(info, lv, nodes, empty_set);
-}
+DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
/*
___ _ ____
*/
-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 *insert_Perm_after(ir_graph *irg, const arch_register_class_t *cls,
ir_node *pos)
{
+ be_lv_t *lv = be_get_irg_liveness(irg);
ir_node *bl = is_Block(pos) ? pos : get_nodes_block(pos);
- ir_graph *irg = get_irn_irg(bl);
- pset *live = pset_new_ptr_default();
- FIRM_DBG_REGISTER(firm_dbg_module_t *dbg, "be.node");
+ ir_nodeset_t live;
+ ir_nodeset_iterator_t iter;
- ir_node *curr, *irn, *perm, **nodes;
- int i, n;
+ ir_node *irn, *perm, **nodes;
+ size_t i, n;
DBG((dbg, LEVEL_1, "Insert Perm after: %+F\n", pos));
- be_liveness_nodes_live_at(lv, arch_env, cls, pos, live);
+ ir_nodeset_init(&live);
+ be_liveness_nodes_live_at(lv, cls, pos, &live);
- n = pset_count(live);
-
- if(n == 0) {
- del_pset(live);
+ n = ir_nodeset_size(&live);
+ if (n == 0) {
+ ir_nodeset_destroy(&live);
return NULL;
}
- nodes = xmalloc(n * sizeof(nodes[0]));
+ nodes = XMALLOCN(ir_node*, n);
DBG((dbg, LEVEL_1, "live:\n"));
- for(irn = pset_first(live), i = 0; irn; irn = pset_next(live), i++) {
+ i = 0;
+ foreach_ir_nodeset(&live, irn, iter) {
DBG((dbg, LEVEL_1, "\t%+F\n", irn));
nodes[i] = irn;
+ i++;
}
- del_pset(live);
+ ir_nodeset_destroy(&live);
- perm = be_new_Perm(cls, irg, bl, n, nodes);
+ perm = be_new_Perm(cls, bl, n, nodes);
sched_add_after(pos, perm);
free(nodes);
- curr = perm;
for (i = 0; i < n; ++i) {
- ir_node *copies[2];
ir_node *perm_op = get_irn_n(perm, i);
- const arch_register_t *reg = arch_get_irn_register(arch_env, perm_op);
+ const arch_register_t *reg = arch_get_irn_register(perm_op);
+ be_ssa_construction_env_t senv;
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] = perm_op;
- copies[1] = proj;
-
- be_ssa_constr(dom_front, lv, 2, copies);
+ ir_node *proj = new_r_Proj(perm, mode, i);
+ arch_set_irn_register(proj, reg);
+
+ 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 perm;
}
-struct _elr_closure_t {
- struct obstack obst;
- const be_chordal_env_t *cenv;
-};
-
-static void elr_split_walker(ir_node *bl, void *data)
-{
- struct _elr_closure_t *c = data;
- const be_chordal_env_t *cenv = c->cenv;
- const arch_env_t *aenv = cenv->birg->main_env->arch_env;
- be_lv_t *lv = cenv->birg->lv;
- be_dom_front_info_t *dom_front = cenv->birg->dom_front;
- be_insn_t *insn;
- be_insn_env_t ie;
-
- be_insn_env_init(&ie, cenv->birg, cenv->cls, &c->obst);
-
- for(insn = be_scan_insn(&ie, sched_first(bl)); !is_Block(insn->irn); insn = be_scan_insn(&ie, insn->next_insn)) {
- ir_node *pred = sched_prev(insn->irn);
- if(!is_Block(pred) && !is_Phi(insn->irn))
- insert_Perm_after(aenv, lv, cenv->cls, dom_front, insn->irn);
- }
-}
-
-void extreme_liverange_splitting(struct _be_chordal_env_t *cenv)
-{
- struct _elr_closure_t c;
- be_lv_t *lv = cenv->birg->lv;
-
- c.cenv = cenv;
- obstack_init(&c.obst);
- be_liveness_recompute(lv);
- irg_block_walk_graph(cenv->irg, elr_split_walker, NULL, &c);
- be_liveness_recompute(lv);
- obstack_free(&c.obst, NULL);
-}
+static int blocks_removed;
/**
* Post-block-walker: Find blocks containing only one jump and
* remove them.
*/
-static void remove_empty_block(ir_node *block, void *data) {
+static void remove_empty_block(ir_node *block)
+{
const ir_edge_t *edge, *next;
+ int i, arity;
ir_node *node;
- int *changed = data;
+ ir_node *pred;
+ ir_node *succ_block;
ir_node *jump = NULL;
+ ir_graph *irg = get_irn_irg(block);
- assert(is_Block(block));
+ if (irn_visited_else_mark(block))
+ return;
if (get_Block_n_cfgpreds(block) != 1)
- return;
+ goto check_preds;
sched_foreach(block, node) {
- if (! is_Jmp(node))
- return;
+ 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 */
- assert(0 && "We should never have 2 jumps in a block");
- return;
+ panic("found 2 jumps in a block");
}
jump = node;
}
if (jump == NULL)
- return;
+ goto check_preds;
- node = get_Block_cfgpred(block, 0);
+ pred = get_Block_cfgpred(block, 0);
+ succ_block = NULL;
foreach_out_edge_safe(jump, edge, next) {
- ir_node *block = get_edge_src_irn(edge);
- int pos = get_edge_src_pos(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
+ && get_Block_entity(block) != 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_n(block, pos, node);
+ set_irn_n(succ_block, pos, pred);
}
- set_Block_cfgpred(block, 0, new_Bad());
- sched_remove(jump);
- *changed = 1;
+ if (get_Block_entity(block) != NULL) {
+ /* move the label to the successor block */
+ ir_entity *entity = get_Block_entity(block);
+ set_Block_entity(succ_block, entity);
+ }
+
+ /* 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, next) {
+ node = get_edge_src_irn(edge);
+
+ 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;
+ }
+ if (is_Sync(node)) {
+ set_nodes_block(node, get_nodes_block(pred));
+ continue;
+ }
+ 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;
+ }
+ panic("Unexpected node %+F in block %+F with empty schedule", node, block);
+ }
+
+ set_Block_cfgpred(block, 0, new_r_Bad(irg, mode_X));
+ kill_node(jump);
+ blocks_removed = 1;
+
+ /* check predecessor */
+ remove_empty_block(get_nodes_block(pred));
+ return;
+
+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);
+ }
}
/* removes basic blocks that just contain a jump instruction */
-int be_remove_empty_blocks(ir_graph *irg) {
- int changed = 0;
+int be_remove_empty_blocks(ir_graph *irg)
+{
+ ir_node *end;
+ int i, arity;
+
+ blocks_removed = 0;
+
+ ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
+ inc_irg_visited(irg);
+ 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);
- irg_block_walk_graph(irg, remove_empty_block, NULL, &changed);
- if (changed) {
+ if (blocks_removed) {
/* invalidate analysis info */
- set_irg_doms_inconsistent(irg);
- set_irg_extblk_inconsistent(irg);
- set_irg_outs_inconsistent(irg);
+ clear_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_DOMINANCE
+ | IR_GRAPH_STATE_VALID_EXTENDED_BLOCKS);
}
- return changed;
+ return blocks_removed;
}
-typedef struct _be_dead_out_env_t {
- ir_graph *irg;
+//---------------------------------------------------------------------------
+
+typedef struct remove_dead_nodes_env_t_ {
bitset_t *reachable;
- DEBUG_ONLY(firm_dbg_module_t *dbg);
-} be_dead_out_env_t;
+ ir_graph *irg;
+ be_lv_t *lv;
+} remove_dead_nodes_env_t;
/**
- * Check if @p node has dead users, i.e. they are reachable only via outedges from @p node.
- * Set all ins of those users to BAD.
+ * Post-walker: remember all visited nodes in a bitset.
*/
-static void kill_dead_out(ir_node *node, be_dead_out_env_t *env) {
- ir_graph *irg = env->irg;
- const ir_edge_t *edge, *tmp_edge;
+static void mark_dead_nodes_walker(ir_node *node, void *data)
+{
+ remove_dead_nodes_env_t *env = (remove_dead_nodes_env_t*) data;
+ bitset_set(env->reachable, get_irn_idx(node));
+}
- if (irn_visited(node))
- return;
- mark_irn_visited(node);
+/**
+ * Post-block-walker:
+ * Walk through the schedule of every block and remove all dead nodes from it.
+ */
+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;
- /* check all out edges */
- foreach_out_edge_safe(node, edge, tmp_edge) {
- ir_node *src = get_edge_src_irn(edge);
+ 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 (! bitset_is_set(env->reachable, get_irn_idx(src))) {
- /* BEWARE: do not kill anchors or TLS */
- if (src != get_irg_globals(irg) && src != get_irg_tls(irg)) {
- DBG((env->dbg, LEVEL_1, "killing %+F, only reachable from %+F\n", src, node));
- be_kill_node(src);
- }
+ if (bitset_is_set(env->reachable, get_irn_idx(node)))
continue;
- }
- /* descent */
- if (! is_Block(src)) {
- kill_dead_out(src, env);
+ if (env->lv != NULL)
+ be_liveness_remove(env->lv, node);
+ sched_remove(node);
+
+ /* kill projs */
+ if (get_irn_mode(node) == mode_T) {
+ const ir_edge_t *edge;
+ const ir_edge_t *next_edge;
+ foreach_out_edge_safe(node, edge, next_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);
+ }
}
+ kill_node(node);
}
}
-static void set_reachable(ir_node *node, void *data) {
- bitset_t *reachable = data;
- bitset_set(reachable, get_irn_idx(node));
-}
-
-/**
- * Set input of all nodes only reachable via out edges to BAD.
- */
-void be_kill_dead_nodes(ir_graph *irg) {
- be_dead_out_env_t env;
-
- env.irg = irg;
+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));
- FIRM_DBG_REGISTER(env.dbg, "firm.be.killdead");
+ env.lv = be_get_irg_liveness(irg);
+ env.irg = irg;
- /* collect all reachable nodes */
- irg_walk_in_or_dep_graph(irg, set_reachable, NULL, env.reachable);
+ // mark all reachable nodes
+ irg_walk_graph(irg, mark_dead_nodes_walker, NULL, &env);
- /* this is a forward walk (start -> end) */
- inc_irg_visited(irg);
- kill_dead_out(get_irg_start(irg), &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(dbg, "firm.be.irgmod");
}
projects / libfirm / blobdiff