/*
- * Project: libFIRM
- * File name: ir/opt/ifconv.c
- * Purpose: If conversion
- * Author: Sebastian Hack.
- * Created:
- * CVS-ID: $Id$
- * Copyright: (c) 1998-2005 Universität Karlsruhe
- * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
+ * 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.
*/
-#if 1
+/*
+ * @file ir/opt/ifconv.c
+ * @brief If conversion
+ * @author Christoph Mallon
+ * @version $Id$
+ */
-#ifdef HAVE_CONFIG_H
#include "config.h"
-#endif
-#ifdef HAVE_MALLOC_H
-#include <malloc.h>
-#endif
-#ifdef HAVE_ALLOCA_H
-#include <alloca.h>
-#endif
#include <assert.h>
-
+#include "iroptimize.h"
#include "obst.h"
#include "irnode_t.h"
#include "cdep.h"
#include "ircons.h"
-#include "ifconv.h"
#include "irdom.h"
#include "irgmod.h"
#include "irgopt.h"
#include "irgwalk.h"
#include "irtools.h"
-#include "return.h"
-#include "array.h"
+#include "array_t.h"
// debug
#include "irdump.h"
#include "debug.h"
-DEBUG_ONLY(firm_dbg_module_t *dbg);
+DEBUG_ONLY(static firm_dbg_module_t *dbg);
-static ir_node* walk_to_projx(ir_node* start)
+/** allow every Mux to be created. */
+static int default_allow_ifconv(ir_node *sel, ir_node* phi_list, int i, int j)
{
- ir_node* pred;
-
- pred = get_nodes_block(start);
-
- /* if there are multiple control flow predecessors nothing sensible can be
- * done */
- if (get_irn_arity(pred) > 1) return NULL;
-
- pred = get_irn_n(pred, 0);
- if (get_irn_op(pred) == op_Proj) {
- assert(get_irn_mode(pred) == mode_X);
- return pred;
- } else {
- return NULL;
- }
+ (void) sel;
+ (void) phi_list;
+ (void) i;
+ (void) j;
+ return 1;
}
/**
- * Additional block info.
+ * Default options.
*/
-typedef struct block_info {
- ir_node *phi; /**< head of the Phi list */
- int has_pinned; /**< set if the block contains instructions that cannot be moved */
-} block_info;
-
-#define get_block_blockinfo(block) ((block_info *)get_irn_link(block))
+static const ir_settings_if_conv_t default_info = {
+ 0, /* doesn't matter for Mux */
+ default_allow_ifconv
+};
/**
* Returns non-zero if a Block can be emptied.
*/
-static int can_empty_block(ir_node *block)
+static int can_empty_block(ir_node *block) {
+ return get_Block_mark(block) == 0;
+}
+
+
+static ir_node* walk_to_projx(ir_node* start, const ir_node* dependency)
{
- return !get_block_blockinfo(block)->has_pinned;
+ int arity;
+ int i;
+
+ /* No need to find the conditional block if this block cannot be emptied and
+ * therefore not moved */
+ if (!can_empty_block(start)) return NULL;
+
+ arity = get_irn_arity(start);
+ for (i = 0; i < arity; ++i) {
+ ir_node* pred = get_irn_n(start, i);
+ ir_node* pred_block = get_nodes_block(pred);
+
+ if (pred_block == dependency) {
+ if (is_Proj(pred)) {
+ assert(get_irn_mode(pred) == mode_X);
+ return pred;
+ }
+ return NULL;
+ }
+
+ if (is_Proj(pred)) {
+ assert(get_irn_mode(pred) == mode_X);
+ return NULL;
+ }
+
+ if (is_cdep_on(pred_block, dependency)) {
+ return walk_to_projx(pred_block, dependency);
+ }
+ }
+ return NULL;
}
if (get_nodes_block(node) != src_block) return node;
if (get_irn_op(node) == op_Phi) return get_irn_n(node, i);
- copy_irn_to_irg(node, current_ir_graph);
- copy = get_irn_link(node);
+ copy = exact_copy(node);
dst_block = get_nodes_block(get_irn_n(src_block, i));
set_nodes_block(copy, dst_block);
}
-/**
- * Duplicate and move the contents of ith block predecessor into its
- * predecessors if the block has multiple control dependencies and only one
- * successor.
- * Also bail out if the block contains non-movable nodes, because later
- * if-conversion would be pointless.
- */
-static int fission_block(ir_node* block, int i)
-{
- ir_node* pred = get_irn_n(block, i);
- ir_node* pred_block;
- block_info* info;
- ir_node* phi;
- int pred_arity;
- int arity;
- ir_node** ins;
- int j;
-
- if (get_irn_op(pred) != op_Jmp) return 0;
- pred_block = get_nodes_block(pred);
-
- if (!has_multiple_cdep(pred_block)) return 0;
- if (!can_empty_block(pred_block)) return 0;
-
- DB((dbg, LEVEL_1, "Fissioning block %+F\n", pred_block));
-
- pred_arity = get_irn_arity(pred_block);
- arity = get_irn_arity(block);
- info = get_block_blockinfo(block);
- NEW_ARR_A(ir_node *, ins, arity + pred_arity - 1);
- for (phi = info->phi; phi != NULL; phi = get_irn_link(phi)) {
- for (j = 0; j < i; ++j) ins[j] = get_irn_n(phi, j);
- for (j = 0; j < pred_arity; ++j) {
- ins[i + j] = copy_to(get_irn_n(phi, i), pred_block, j);
- }
- for (j = i + 1; j < arity; ++j) {
- ins[pred_arity - 1 + j] = get_irn_n(phi, j);
- }
- set_irn_in(phi, arity + pred_arity - 1, ins);
- }
- for (j = 0; j < i; ++j) ins[j] = get_irn_n(block, j);
- for (j = 0; j < pred_arity; ++j) ins[i + j] = get_irn_n(pred_block, j);
- for (j = i + 1; j < arity; ++j) ins[pred_arity - 1 + j] = get_irn_n(block, j);
- set_irn_in(block, arity + pred_arity - 1, ins);
-
- /* Kill all Phis in the fissioned block
- * This is to make sure they're not kept alive
- */
- info = get_block_blockinfo(pred_block);
- phi = info->phi;
- while (phi != NULL) {
- ir_node* next = get_irn_link(phi);
- exchange(phi, new_Bad());
- phi = next;
- }
- return 1;
-}
-
-
/**
* Remove predecessors i and j from node and add predecessor new_pred
*/
NEW_ARR_A(ir_node *, ins, arity - 1);
l = 0;
- for (k = 0; k < i; ++k) ins[l++] = get_irn_n(node, k);
- for (++k; k < j; ++k) ins[l++] = get_irn_n(node, k);
- for (++k; k < arity; ++k) ins[l++] = get_irn_n(node, k);
+ for (k = 0; k < i; ++k) ins[l++] = get_irn_n(node, k);
+ for (++k; k < j; ++k) ins[l++] = get_irn_n(node, k);
+ for (++k; k < arity; ++k) ins[l++] = get_irn_n(node, k);
ins[l++] = new_pred;
assert(l == arity - 1);
set_irn_in(node, l, ins);
}
-static void if_conv_walker(ir_node* block, void* env)
-{
- ir_node* phi;
- int arity;
- int i;
-
- /* Bail out, if there are no Phis at all */
- if (get_block_blockinfo(block)->phi == NULL) return;
-
-restart:
- arity = get_irn_arity(block);
- for (i = 0; i < arity; ++i) {
- if (fission_block(block, i)) goto restart;
- }
- //return;
-
- arity = get_irn_arity(block);
- for (i = 0; i < arity; ++i) {
- ir_node* pred;
- ir_node* cond;
- ir_node* projx0;
- int j;
-
- projx0 = walk_to_projx(get_irn_n(block, i));
- if (projx0 == NULL) return;
- pred = get_Proj_pred(projx0);
- if (get_irn_op(pred) != op_Cond || get_irn_mode(get_Cond_selector(pred)) != mode_b) continue;
- cond = pred;
-
- if (!can_empty_block(get_nodes_block(get_irn_n(block, i)))) {
- DB((dbg, LEVEL_1, "Cannot empty block %+F\n",
- get_nodes_block(get_irn_n(block, i))
- ));
- continue;
- }
-
- for (j = i + 1; j < arity; ++j) {
- ir_node* projx1;
- ir_node* psi_block;
- ir_node* conds[1];
- ir_node* vals[2];
- ir_node* psi;
-
- projx1 = walk_to_projx(get_irn_n(block, j));
- if (projx1 == NULL) continue;
- pred = get_Proj_pred(projx1);
- if (get_irn_op(pred) != op_Cond || get_irn_mode(get_Cond_selector(pred)) != mode_b) continue;
- if (pred != cond) continue;
- DB((dbg, LEVEL_1, "Found Cond %+F with proj %+F and %+F\n", cond, projx0, projx1));
-
- if (!can_empty_block(get_nodes_block(get_irn_n(block, j)))) {
- DB((dbg, LEVEL_1, "Cannot empty %+F\n", get_nodes_block(get_irn_n(block, j))));
- continue;
- }
-
- conds[0] = get_Cond_selector(cond);
-
- psi_block = get_nodes_block(cond);
- phi = get_block_blockinfo(block)->phi;
- do {
- // Don't generate PsiMs
- if (get_irn_mode(phi) == mode_M) {
- /* Something is very fishy if to predecessors of a PhiM point into the
- * block but not at the same memory node
- */
- assert(get_irn_n(phi, i) == get_irn_n(phi, j));
- // fake memory Psi
- psi = get_irn_n(phi, i);
- DB((dbg, LEVEL_2, "Handling memory Phi %+F\n", phi));
- } else {
- ir_node* val_i = get_irn_n(phi, i);
- ir_node* val_j = get_irn_n(phi, j);
-
- if (val_i == val_j) {
- psi = val_i;
- DB((dbg, LEVEL_2, "Generating no psi, because both values are equal\n"));
- } else {
- if (get_Proj_proj(projx0) == pn_Cond_true) {
- vals[0] = val_i;
- vals[1] = val_j;
- } else {
- vals[0] = val_j;
- vals[1] = val_i;
- }
- psi = new_r_Psi(
- current_ir_graph, psi_block, 1, conds, vals, get_irn_mode(phi)
- );
- DB((dbg, LEVEL_2, "Generating %+F for %+F\n", psi, phi));
- }
- }
-
- if (arity == 2) {
- exchange(phi, psi);
- } else {
- rewire(phi, i, j, psi);
- }
-
- phi = get_irn_link(phi);
- } while (phi != NULL);
-
- exchange(get_nodes_block(get_irn_n(block, i)), psi_block);
- exchange(get_nodes_block(get_irn_n(block, j)), psi_block);
-
- if (arity == 2) {
- DB((dbg, LEVEL_1, "Welding block %+F to %+F\n", block, psi_block));
- get_block_blockinfo(psi_block)->has_pinned |= get_block_blockinfo(block)->has_pinned;
- exchange(block, psi_block);
- return;
- } else {
- rewire(block, i, j, new_r_Jmp(current_ir_graph, psi_block));
- goto restart;
- }
- }
- }
-}
-
/**
- * Block walker: add additional data
+ * Remove the jth predecessors from the ith predecessor of block and add it to block
*/
-static void init_block_link(ir_node *block, void *env)
+static void split_block(ir_node* block, int i, int j)
{
- struct obstack *obst = env;
- block_info *bi = obstack_alloc(obst, sizeof(*bi));
-
- bi->phi = NULL;
- bi->has_pinned = 0;
- set_irn_link(block, bi);
-}
+ ir_node* pred_block = get_nodes_block(get_irn_n(block, i));
+ int arity = get_irn_arity(block);
+ int new_pred_arity;
+ ir_node *phi, *next;
+ ir_node **ins;
+ ir_node **pred_ins;
+ int k;
+ DB((dbg, LEVEL_1, "Splitting predecessor %d of predecessor %d of %+F\n", j, i, block));
-/**
- * Daisy-chain all phis in a block
- * If a non-movable node is encountered set the has_pinned flag
- */
-static void collect_phis(ir_node *node, void *env)
-{
- if (is_Phi(node)) {
- ir_node *block = get_nodes_block(node);
- block_info *bi = get_block_blockinfo(block);
+ NEW_ARR_A(ir_node*, ins, arity + 1);
- set_irn_link(node, bi->phi);
- bi->phi = node;
- }
- else {
- if (is_no_Block(node) && get_irn_pinned(node) == op_pin_state_pinned) {
- /*
- * Ignore control flow nodes, these will be removed.
- * This ignores Raise. That is surely bad. FIXME.
- */
- if (! is_cfop(node)) {
- ir_node *block = get_nodes_block(node);
- block_info *bi = get_block_blockinfo(block);
+ for (phi = get_Block_phis(block); phi != NULL; phi = get_Phi_next(phi)) {
+ ir_node* copy = copy_to(get_irn_n(phi, i), pred_block, j);
- DB((dbg, LEVEL_2, "Node %+F in block %+F is unmovable\n", node, block));
- bi->has_pinned = 1;
- }
- }
+ for (k = 0; k < i; ++k) ins[k] = get_irn_n(phi, k);
+ ins[k++] = copy;
+ for (; k < arity; ++k) ins[k] = get_irn_n(phi, k);
+ ins[k] = get_irn_n(phi, i);
+ assert(k == arity);
+ set_irn_in(phi, arity + 1, ins);
}
-}
-
-
-/*
- * Transform multiple cascaded Psis into one Psi
- */
-static ir_node* fold_psi(ir_node* psi)
-{
- int arity = get_Psi_n_conds(psi);
- int new_arity = 0;
- int i;
- ir_node* n;
- ir_node** conds;
- ir_node** vals;
- int j;
- int k;
- int a;
- ir_node* new_psi;
- for (i = 0; i < arity; ++i) {
- n = get_Psi_val(psi, i);
- if (get_irn_op(n) == op_Psi) {
- new_arity += get_Psi_n_conds(n) + 1;
+ for (k = 0; k < i; ++k) ins[k] = get_irn_n(block, k);
+ ins[k++] = get_irn_n(pred_block, j);
+ for (; k < arity; ++k) ins[k] = get_irn_n(block, k);
+ ins[k] = get_irn_n(block, i);
+ assert(k == arity);
+ set_irn_in(block, arity + 1, ins);
+
+ new_pred_arity = get_irn_arity(pred_block) - 1;
+ NEW_ARR_A(ir_node*, pred_ins, new_pred_arity);
+
+ for (phi = get_Block_phis(pred_block); phi != NULL; phi = next) {
+ for (k = 0; k < j; ++k) pred_ins[k] = get_irn_n(phi, k);
+ for (; k < new_pred_arity; ++k) pred_ins[k] = get_irn_n(phi, k + 1);
+ assert(k == new_pred_arity);
+ next = get_Phi_next(phi);
+ if (new_pred_arity > 1) {
+ set_irn_in(phi, new_pred_arity, pred_ins);
} else {
- ++new_arity;
+ exchange(phi, pred_ins[0]);
}
}
- n = get_Psi_default(psi);
- if (get_irn_op(n) == op_Psi) {
- new_arity += get_Psi_n_conds(n);
- }
-
- if (arity == new_arity) return psi; // no attached Psis found
- DB((dbg, LEVEL_1, "Folding %+F from %d to %d conds\n", psi, arity, new_arity));
- NEW_ARR_A(ir_node *, conds, new_arity);
- NEW_ARR_A(ir_node *, vals, new_arity + 1);
- j = 0;
- for (i = 0; i < arity; ++i) {
- ir_node* c = get_Psi_cond(psi, i);
-
- n = get_Psi_val(psi, i);
- if (get_irn_op(n) == op_Psi) {
- a = get_Psi_n_conds(n);
- for (k = 0; k < a; ++k) {
- conds[j] = new_r_And(
- current_ir_graph, get_nodes_block(psi),
- c, get_Psi_cond(n, k), mode_b
- );
- vals[j] = get_Psi_val(n, k);
- ++j;
- }
- conds[j] = c;
- vals[j] = get_Psi_default(n);
- } else {
- conds[j] = c;
- vals[j] = n;
- }
- ++j;
- }
- n = get_Psi_default(psi);
- if (get_irn_op(n) == op_Psi) {
- a = get_Psi_n_conds(n);
- for (k = 0; k < a; ++k) {
- conds[j] = get_Psi_cond(n, k);
- vals[j] = get_Psi_val(n, k);
- ++j;
- }
- vals[j] = get_Psi_default(n);
+ for (k = 0; k < j; ++k) pred_ins[k] = get_irn_n(pred_block, k);
+ for (; k < new_pred_arity; ++k) pred_ins[k] = get_irn_n(pred_block, k + 1);
+ assert(k == new_pred_arity);
+ if (new_pred_arity > 1) {
+ set_irn_in(pred_block, new_pred_arity, pred_ins);
} else {
- vals[j] = n;
+ exchange(pred_block, get_nodes_block(pred_ins[0]));
}
- assert(j == new_arity);
- new_psi = new_r_Psi(
- current_ir_graph, get_nodes_block(psi),
- new_arity, conds, vals, get_irn_mode(psi)
- );
- DB((dbg, LEVEL_1, "Folded %+F into new %+F\n", psi, new_psi));
- exchange(psi, new_psi);
- return new_psi;
}
-/*
- * Merge consecutive psi inputs if the data inputs are the same
- */
-static void meld_psi(ir_node* psi)
+static void prepare_path(ir_node* block, int i, const ir_node* dependency)
{
- int arity = get_Psi_n_conds(psi);
- int new_arity;
- ir_node** conds;
- ir_node** vals;
- ir_node* cond;
- ir_node* val;
- int i;
+ ir_node* pred = get_nodes_block(get_irn_n(block, i));
+ int pred_arity;
int j;
- ir_node* new_psi;
-
- new_arity = 1;
- val = get_Psi_val(psi, 0);
- DB((dbg, LEVEL_1, "Pred 0 of %+F is %+F\n", psi, val));
- for (i = 1; i < arity; ++i) {
- ir_node* v = get_Psi_val(psi, i);
- DB((dbg, LEVEL_1, "Pred %2d of %+F is %+F\n", i, psi, v));
- if (val != v) {
- val = v;
- ++new_arity;
- }
- }
- DB((dbg, LEVEL_1, "Default of %+F is %+F\n", psi, get_Psi_default(psi)));
- if (val == get_Psi_default(psi)) --new_arity;
-
- DB((dbg, LEVEL_1, "Melding Psi %+F from %d conds to %d\n", psi, arity, new_arity));
- if (new_arity == arity) return;
+ DB((dbg, LEVEL_1, "Preparing predecessor %d of %+F\n", i, block));
- /* If all data inputs of the Psi are equal, exchange the Psi with that value */
- if (new_arity == 0) {
- exchange(psi, val);
- return;
- }
+ pred_arity = get_irn_arity(pred);
+ for (j = 0; j < pred_arity; ++j) {
+ ir_node* pred_pred = get_nodes_block(get_irn_n(pred, j));
- NEW_ARR_A(ir_node *, conds, new_arity);
- NEW_ARR_A(ir_node *, vals, new_arity + 1);
- cond = get_Psi_cond(psi, 0);
- val = get_Psi_val(psi, 0);
- j = 0;
- for (i = 1; i < arity; ++i) {
- ir_node* v = get_Psi_val(psi, i);
-
- if (v == val) {
- cond = new_r_Or(
- current_ir_graph, get_nodes_block(psi),
- cond, get_Psi_cond(psi, i), mode_b
- );
- } else {
- conds[j] = cond;
- vals[j] = val;
- ++j;
- val = v;
+ if (is_cdep_on(pred_pred, dependency)) {
+ prepare_path(pred, j, dependency);
+ split_block(block, i, j);
+ break;
}
}
- if (val != get_Psi_default(psi)) {
- conds[j] = cond;
- vals[j] = val;
- ++j;
- }
- vals[j] = get_Psi_default(psi);
- assert(j == new_arity);
- new_psi = new_r_Psi(
- current_ir_graph, get_nodes_block(psi),
- new_arity, conds, vals, get_irn_mode(psi)
- );
- DB((dbg, LEVEL_1, "Molded %+F into %+F\n", psi, new_psi));
- exchange(psi, new_psi);
-}
-
-
-static void optimise_psis(ir_node* node, void* env)
-{
- if (get_irn_op(node) != op_Psi) return;
-#if 1
- node = fold_psi(node);
-#endif
-#if 1
- meld_psi(node);
-#endif
}
-void opt_if_conv(ir_graph *irg, const opt_if_conv_info_t *params)
+static void if_conv_walker(ir_node* block, void* env)
{
- struct obstack obst;
-
- FIRM_DBG_REGISTER(dbg, "firm.opt.ifconv");
-
- DB((dbg, LEVEL_1, "Running if-conversion on %+F\n", irg));
-
- dump_ir_block_graph(irg, "_00_pre");
-
- normalize_one_return(irg);
- remove_critical_cf_edges(irg);
-
- dump_ir_block_graph(irg, "_01_normal");
-
- compute_cdep(irg);
- assure_doms(irg);
-
- obstack_init(&obst);
- irg_block_walk_graph(irg, init_block_link, NULL, &obst);
- irg_walk_graph(irg, collect_phis, NULL, NULL);
- irg_block_walk_graph(irg, NULL, if_conv_walker, NULL);
-
- local_optimize_graph(irg);
- dump_ir_block_graph(irg, "_02_ifconv");
-
- irg_walk_graph(irg, NULL, optimise_psis, NULL);
-
- dump_ir_block_graph(irg, "_03_postifconv");
-
- obstack_free(&obst, NULL);
+ ir_settings_if_conv_t* opt_info = env;
+ int arity;
+ int i;
- free_dom(irg);
- free_cdep(irg);
-}
+ /* Bail out, if there are no Phis at all */
+ if (get_Block_phis(block) == NULL) return;
-#else
+restart:
+ arity = get_irn_arity(block);
+ for (i = 0; i < arity; ++i) {
+ ir_node* pred0;
+ ir_cdep* cdep;
-/**
- * @file ifconv.c
- * If conversion.
- * Make Mux nodes from Conds where it its possible.
- * @author Sebastian Hack
- * @date 4.2.2005
- */
-#ifdef HAVE_CONFIG_H
-#include "config.h"
-#endif
+ pred0 = get_Block_cfgpred_block(block, i);
+ for (cdep = find_cdep(pred0); cdep != NULL; cdep = cdep->next) {
+ const ir_node* dependency = cdep->node;
+ ir_node* projx0 = walk_to_projx(pred0, dependency);
+ ir_node* cond;
+ int j;
-#ifdef HAVE_STDLIB_H
-#include <stdlib.h>
-#endif
-#ifdef HAVE_STRING_H
-#include <string.h>
-#endif
-#ifdef HAVE_ALLOCA_H
-#include <alloca.h>
-#endif
+ if (projx0 == NULL) continue;
-#include "irgraph_t.h"
-#include "irnode_t.h"
-#include "irgwalk.h"
-#include "iropt_t.h"
-#include "irgmod.h"
-#include "irmode_t.h"
-#include "ircons_t.h"
-#include "irdom_t.h"
-#include "irgwalk.h"
+ cond = get_Proj_pred(projx0);
+ if (! is_Cond(cond))
+ continue;
-#include "ifconv.h"
-#include "irflag_t.h"
+ /* We only handle boolean decisions, no switches */
+ if (get_irn_mode(get_Cond_selector(cond)) != mode_b) continue;
-#include "irprintf.h"
-#include "debug.h"
-#include "obst.h"
-#include "set.h"
-#include "bitset.h"
-#include "bitfiddle.h"
-#include "irhooks.h"
-#include "return.h"
+ for (j = i + 1; j < arity; ++j) {
+ ir_node* projx1;
+ ir_node* sel;
+ ir_node* mux_block;
+ ir_node* phi;
+ ir_node* pred1;
+ dbg_info* cond_dbg;
-#define MAX_DEPTH 4
+ pred1 = get_Block_cfgpred_block(block, j);
-/**
- * check, if a node is const and return its tarval or
- * return a default tarval.
- * @param cnst The node whose tarval to get.
- * @param or The alternative tarval, if the node is no Const.
- * @return The tarval of @p cnst, if the node is Const, @p otherwise.
- */
-static tarval *get_value_or(ir_node *cnst, tarval *or)
-{
- return get_irn_op(cnst) == op_Const ? get_Const_tarval(cnst) : or;
-}
+ if (!is_cdep_on(pred1, dependency)) continue;
+ projx1 = walk_to_projx(pred1, dependency);
-/**
- * Try to optimize nested muxes into a dis- or conjunction
- * of two muxes.
- * @param mux The parent mux, which has muxes as operands.
- * @return The replacement node for this mux. If the optimization is
- * successful, this might be an And or Or node, if not, its the mux
- * himself.
- */
-static ir_node *optimize_mux_chain(ir_node *mux)
-{
- int i;
- ir_node *res;
- ir_node *ops[2];
- ir_mode *mode = get_irn_mode(mux);
- tarval *null;
- tarval *minus_one;
-
- /*
- * If we have no mux, or its mode is not integer, we
- * can return.
- */
- if(get_irn_op(mux) != op_Mux || !mode_is_int(mode))
- return mux;
-
- res = mux;
- null = get_mode_null(mode);
- minus_one = tarval_sub(null, get_tarval_one(mode));
-
- ops[0] = get_Mux_false(mux);
- ops[1] = get_Mux_true(mux);
-
- for(i = 0; i < 2; ++i) {
- ir_node *a, *b, *d;
- tarval *tva, *tvb, *tvd;
- ir_node *child_mux;
-
- /*
- * A mux operand at the first position can be factored
- * out, if the operands fulfill several conditions:
- *
- * mux(c1, mux(c2, a, b), d)
- *
- * This can be made into:
- * 1) mux(c1, 0, d) | mux(c2, a, b)
- * if a | d == d and b | d == d
- *
- * 2) mux(c1, -1, d) & mux(c2, a, b)
- * if a & d == d and a & b == b
- */
- if(get_irn_op(ops[i]) == op_Mux) {
-
- child_mux = ops[i];
- a = get_Mux_false(child_mux);
- b = get_Mux_true(child_mux);
- d = ops[1 - i];
-
- /* Try the or stuff */
- tva = get_value_or(a, minus_one);
- tvb = get_value_or(b, minus_one);
- tvd = get_value_or(d, null);
-
- if(tarval_cmp(tarval_or(tva, tvd), tvd) == pn_Cmp_Eq
- && tarval_cmp(tarval_or(tvb, tvd), tvd) == pn_Cmp_Eq) {
-
- ops[i] = new_Const(mode, null);
- res = new_r_Or(current_ir_graph, get_nodes_block(mux),
- mux, child_mux, mode);
- break;
- }
-
- /* If the or didn't go, try the and stuff */
- tva = get_value_or(a, null);
- tvb = get_value_or(b, null);
- tvd = get_value_or(d, minus_one);
-
- if(tarval_cmp(tarval_and(tva, tvd), tvd) == pn_Cmp_Eq
- && tarval_cmp(tarval_and(tvb, tvd), tvd) == pn_Cmp_Eq) {
-
- ops[i] = new_Const(mode, minus_one);
- res = new_r_And(current_ir_graph, get_nodes_block(mux),
- mux, child_mux, mode);
- break;
- }
- }
- }
-
- /* recursively optimize nested muxes. */
- set_irn_n(mux, 1, optimize_mux_chain(ops[0]));
- set_irn_n(mux, 2, optimize_mux_chain(ops[1]));
-
- return res;
-}
+ if (projx1 == NULL) continue;
+ phi = get_Block_phis(block);
+ if (!opt_info->allow_ifconv(get_Cond_selector(cond), phi, i, j)) continue;
-/***********************************************************
- * The If conversion itself.
- ***********************************************************/
+ DB((dbg, LEVEL_1, "Found Cond %+F with proj %+F and %+F\n",
+ cond, projx0, projx1
+ ));
-/** allow every Mux to be created. */
-static int default_allow_mux(ir_node *sel, ir_node *false_res, ir_node *true_res) {
- return 1;
-}
+ prepare_path(block, i, dependency);
+ prepare_path(block, j, dependency);
+ arity = get_irn_arity(block);
-/**
- * Default options.
- */
-static const opt_if_conv_info_t default_info = {
- MAX_DEPTH,
- default_allow_mux
-};
+ sel = get_Cond_selector(cond);
-/** The debugging module. */
-DEBUG_ONLY(static firm_dbg_module_t *dbg;)
+ mux_block = get_nodes_block(cond);
+ cond_dbg = get_irn_dbg_info(cond);
+ do {
+ ir_node* val_i = get_irn_n(phi, i);
+ ir_node* val_j = get_irn_n(phi, j);
+ ir_node* mux;
+ ir_node* next_phi;
-/**
- * A simple check for side effects upto an opcode of a ir node.
- * @param irn The ir node to check,
- * @return 1 if the opcode itself may produce side effects, 0 if not.
- */
-static INLINE int has_side_effects(const ir_node *irn)
-{
- ir_op *op = get_irn_op(irn);
+ if (val_i == val_j) {
+ mux = val_i;
+ DB((dbg, LEVEL_2, "Generating no Mux, because both values are equal\n"));
+ } else {
+ ir_node *t, *f;
- if (op == op_Cmp)
- return 0;
+ /* Something is very fishy if two predecessors of a PhiM point into
+ * one block, but not at the same memory node
+ */
+ assert(get_irn_mode(phi) != mode_M);
+ if (get_Proj_proj(projx0) == pn_Cond_true) {
+ t = val_i;
+ f = val_j;
+ } else {
+ t = val_j;
+ f = val_i;
+ }
- return !mode_is_datab(get_irn_mode(irn));
-}
+ mux = new_rd_Mux(cond_dbg, current_ir_graph, mux_block, sel, f, t, get_irn_mode(phi));
+ DB((dbg, LEVEL_2, "Generating %+F for %+F\n", mux, phi));
+ }
-/**
- * Possible failure reasons
- */
-enum failure_reason_t {
- SUCCESS = IF_RESULT_SUCCESS,
- TO_DEEP = IF_RESULT_TOO_DEEP,
- SIDE_EFFECTS = IF_RESULT_SIDE_EFFECT,
- PHI_FOUND = IF_RESULT_SIDE_EFFECT_PHI,
- DENIED = IF_RESULT_DENIED
-};
+ next_phi = get_Phi_next(phi);
-/**
- * Decides, if a given expression and its subexpressions
- * (to certain, also given extent) can be moved to a block.
- *
- * @param expr The expression to examine.
- * @param block The block where the expression should go.
- * @param depth The current depth, passed recursively. Use 0 for
- * non-recursive calls.
- * @param info The options for createing Mux nodes.
- * examined.
- *
- * @return a failure reason
- */
-static int _can_move_to(ir_node *expr, ir_node *dest_block, int depth, const opt_if_conv_info_t *info)
-{
- int i, n;
- int res = SUCCESS;
- ir_node *expr_block = get_nodes_block(expr);
-
- /*
- * If we are forced to look too deep into the expression,
- * treat it like it could not be moved.
- */
- if(depth >= info->max_depth) {
- res = TO_DEEP;
- goto end;
- }
-
- /*
- * If the block of the expression dominates the specified
- * destination block, it does not matter if the expression
- * has side effects or anything else. It is executed on each
- * path the destination block is reached.
- */
- if (block_dominates(expr_block, dest_block))
- goto end;
-
- /*
- * We cannot move phis!
- */
- if (is_Phi(expr)) {
- res = PHI_FOUND;
- goto end;
- }
-
- /*
- * This should be superfluous and could be converted into a assertion.
- * The destination block _must_ dominate the block of the expression,
- * else the expression could be used without its definition.
- */
- if (! block_dominates(dest_block, expr_block)) {
- res = IF_RESULT_SIDE_EFFECT;
- goto end;
- }
-
- /*
- * Surely, if the expression does not have a data mode, it is not
- * movable. Perhaps one should also test the floating property of
- * the opcode/node.
- */
- if (has_side_effects(expr)) {
- res = IF_RESULT_SIDE_EFFECT;
- goto end;
- }
-
- /*
- * If the node looks alright so far, look at its operands and
- * check them out. If one of them cannot be moved, this one
- * cannot be moved either.
- */
- for (i = 0, n = get_irn_arity(expr); i < n; ++i) {
- ir_node *op = get_irn_n(expr, i);
- int new_depth = is_Proj(op) ? depth : depth + 1;
-
- res = _can_move_to(op, dest_block, new_depth, info);
-
- if (res != SUCCESS)
- goto end;
- }
-
-end:
- DBG((dbg, LEVEL_3, "\t\t\tcan move to %n: %d\n", expr, res));
-
- return res;
-}
+ if (arity == 2) {
+ exchange(phi, mux);
+ } else {
+ rewire(phi, i, j, mux);
+ }
-/**
- * Convenience function for _can_move_to.
- * Checks, if an expression can be moved to another block. The check can
- * be limited to a expression depth meaning if we need to crawl in
- * deeper into an expression than a given threshold to examine if
- * it can be moved, the expression is rejected and the test returns
- * false.
- *
- * @param expr The expression to check for.
- * @param dest_block The destination block you want @p expr to be.
- * @param info The options for createing Mux nodes.
- *
- * @return return a failure reason
- */
-static INLINE int can_move_to(ir_node *expr, ir_node *dest_block, const opt_if_conv_info_t *info)
-{
- return _can_move_to(expr, dest_block, 0, info);
-}
+ phi = next_phi;
+ } while (phi != NULL);
-/**
- * move a DAG given by a root node expr into a new block
- *
- * @param expr the root of a dag
- * @param dest_block the destination block
- */
-static void move_to(ir_node *expr, ir_node *dest_block)
-{
- int i, n;
- ir_node *expr_block = get_nodes_block(expr);
+ exchange(get_nodes_block(get_irn_n(block, i)), mux_block);
+ exchange(get_nodes_block(get_irn_n(block, j)), mux_block);
- /*
- * If we reached the dominator, we are done.
- * We will never put code through the dominator
- */
- if (block_dominates(expr_block, dest_block))
- return;
+ if (arity == 2) {
+ unsigned mark;
+#if 1
+ DB((dbg, LEVEL_1, "Welding block %+F and %+F\n", block, mux_block));
+ /* copy the block-info from the Mux-block to the block before merging */
- for (i = 0, n = get_irn_arity(expr); i < n; ++i)
- move_to(get_irn_n(expr, i), dest_block);
+ mark = get_Block_mark(mux_block) | get_Block_mark(block);
+ set_Block_mark(block, mark);
+ set_Block_phis(block, get_Block_phis(mux_block));
- set_nodes_block(expr, dest_block);
+ set_irn_in(block, get_irn_arity(mux_block), get_irn_in(mux_block) + 1);
+ exchange_cdep(mux_block, block);
+ exchange(mux_block, block);
+#else
+ DB((dbg, LEVEL_1, "Welding block %+F to %+F\n", block, mux_block));
+ mark = get_Block_mark(mux_block) | get_Block_mark(block);
+ /* mark both block just to be sure, should be enough to mark mux_block */
+ set_Block_mark(mux_block, mark);
+ exchange(block, mux_block);
+#endif
+ return;
+ } else {
+ rewire(block, i, j, new_r_Jmp(current_ir_graph, mux_block));
+ goto restart;
+ }
+ }
+ }
+ }
}
/**
- * return the common dominator of two blocks
+ * Block walker: clear block mark and Phi list
*/
-static INLINE ir_node *common_idom(ir_node *b1, ir_node *b2)
+static void init_block_link(ir_node *block, void *env)
{
- if(block_dominates(b1, b2))
- return b1;
- else if(block_dominates(b2, b1))
- return b2;
- else {
- ir_node *p;
-
- for (p = get_Block_idom(b1); !block_dominates(p, b2); p = get_Block_idom(p));
- return p;
- }
+ (void)env;
+ set_Block_mark(block, 0);
+ set_Block_phis(block, NULL);
}
-/**
- * Information about a cond node.
- */
-typedef struct _cond_t {
- ir_node *cond; /**< The cond node. */
- struct list_head list; /**< List head which is used for queuing this cond
- into the cond bunch it belongs to. */
- unsigned is_new : 1;
- unsigned totally_covers : 1;
- struct _cond_t *link;
- long visited_nr;
-
- /**
- * Information about the both 'branches'
- * (true and false), the cond creates.
- */
- struct {
- int pos; /**< Number of the predecessor of the
- phi block by which this branch is
- reached. It is -1, if this branch is
- only reached through another cond. */
-
- struct _cond_t *masked_by; /**< If this cond's branch is only reached
- through another cond, we store this
- cond ir_node here. */
- } cases[2];
-} cond_t;
/**
- * retrieve the conditional information from a Cond node
+ * Daisy-chain all phis in a block
+ * If a non-movable node is encountered set the has_pinned flag in its block.
*/
-static INLINE cond_t *get_cond(ir_node *irn, set *cond_set)
-{
- cond_t templ;
-
- templ.cond = irn;
- return set_find(cond_set, &templ, sizeof(templ), HASH_PTR(templ.cond));
-}
-
-
-typedef void (cond_walker_t)(cond_t *cond, void *env);
+static void collect_phis(ir_node *node, void *env) {
+ (void) env;
-static void _walk_conds(cond_t *cond, cond_walker_t *pre, cond_walker_t *post,
- long visited_nr, void *env)
-{
- int i;
-
- if(cond->visited_nr >= visited_nr)
- return;
-
- cond->visited_nr = visited_nr;
-
- if(pre)
- pre(cond, env);
-
- for(i = 0; i < 2; ++i) {
- cond_t *c = cond->cases[i].masked_by;
-
- if(c)
- _walk_conds(c, pre, post, visited_nr, env);
- }
-
- if(post)
- post(cond, env);
-}
-
-static long cond_visited_nr = 0;
-
-static void walk_conds(cond_t *cond, cond_walker_t *pre, cond_walker_t *post, void *env)
-{
- _walk_conds(cond, pre, post, ++cond_visited_nr, env);
-}
-
-static void link_conds(cond_t *cond, void *env)
-{
- cond_t **ptr = (cond_t **) env;
+ if (is_Phi(node)) {
+ ir_node *block = get_nodes_block(node);
- cond->link = *ptr;
- *ptr = cond;
-}
+ add_Block_phi(block, node);
+ } else {
+ if (is_no_Block(node) && get_irn_pinned(node) == op_pin_state_pinned) {
+ /*
+ * Ignore control flow nodes, these will be removed.
+ * This ignores Raise. That is surely bad. FIXME.
+ */
+ if (!is_cfop(node)) {
+ ir_node *block = get_nodes_block(node);
-/**
- * Compare two conds for use in a firm set.
- * Two cond_t's are equal, if they designate the same cond node.
- * @param a A cond_t.
- * @param b Another one.
- * @param size Not used.
- * @return 0 (!) if they are equal, != 0 otherwise.
- */
-static int cond_cmp(const void *a, const void *b, size_t size)
-{
- const cond_t *x = a;
- const cond_t *y = b;
- return x->cond != y->cond;
+ DB((dbg, LEVEL_2, "Node %+F in block %+F is unmovable\n", node, block));
+ set_Block_mark(block, 1);
+ }
+ }
+ }
}
-/**
- * Information about conds which can be made to muxes.
- * Instances of this struct are attached to the link field of
- * blocks in which phis are located.
- */
-typedef struct _cond_info_t {
- struct list_head list; /**< Used to list all of these structs per class. */
-
- struct list_head roots; /**< A list of non-depending Conds. Two Conds are
- independent, if it's not possible not reach one from the
- other (all Conds in this list have to dominate the
- block this struct is attached to). */
-
- ir_node *first_phi; /**< The first phi node this cond info was made for. */
- set *cond_set; /**< A set of all dominating reachable Conds. */
-} cond_info_t;
-
-/**
- * @see find_conds.
- */
-static void _find_conds(ir_node *irn, unsigned long visited_nr,
- ir_node *dominator, cond_t *masked_by, int pos, int depth, cond_info_t *ci)
+static void optimise_muxs_0(ir_node* mux, void* env)
{
- ir_node *block;
- int saw_select_cond = 0;
-
- block = get_nodes_block(irn);
-
- /*
- * Only check this block if it is dominated by the specified
- * dominator or it has not been visited yet.
- */
- if (block_dominates(dominator, block) && get_Block_block_visited(block) < visited_nr) {
- cond_t *res = masked_by;
- int i, n;
-
- /* check, if we're on a ProjX
- *
- * Further, the ProjX/Cond block must dominate the base block
- * (the block with the phi in it), otherwise, the Cond
- * is not affecting the phi so that a mux can be inserted.
- */
- if(is_Proj(irn) && get_irn_mode(irn) == mode_X) {
-
- int proj = get_Proj_proj(irn);
- ir_node *cond = get_Proj_pred(irn);
-
- /* true, if the mode is a mode_b cond _NO_ switch cond */
- int is_modeb_cond = get_irn_opcode(cond) == iro_Cond
- && get_irn_mode(get_Cond_selector(cond)) == mode_b;
-
- saw_select_cond = !is_modeb_cond;
-
- /* Check, if the pred of the proj is a Cond
- * with a Projb as selector.
- */
- if(is_modeb_cond) {
- cond_t c;
-
- memset(&c, 0, sizeof(c));
- c.cond = cond;
- c.is_new = 1;
- c.cases[0].pos = -1;
- c.cases[1].pos = -1;
-
- /* get or insert the cond info into the set. */
- res = set_insert(ci->cond_set, &c, sizeof(c), HASH_PTR(cond));
-
- /*
- * If this cond is already masked by the masked_by cond
- * return immediately, since we don't have anything to add.
- */
- if(masked_by && res->cases[proj].masked_by == masked_by)
- return;
-
- if(res->is_new) {
- res->is_new = 0;
- list_add(&res->list, &ci->roots);
- }
-
- /*
- * Set masked by (either NULL or another cond node.
- * If this cond is truly masked by another one, set
- * the position of the actually investigated branch
- * to -1. Since the cond is masked by another one,
- * there could be more ways from the start block
- * to this branch, so we choose -1.
- */
- res->cases[proj].masked_by = masked_by;
-
- if(!masked_by)
- res->cases[proj].pos = pos;
-
- /*
- * Since the masked_by nodes masks a cond, remove it from the
- * root list of the conf trees.
- */
- else {
- assert(res->cases[proj].pos < 0);
- list_del_init(&masked_by->list);
- }
-
- DBG((dbg, LEVEL_2, "%n (%s branch) "
- "for pos %d in block %n reached by %n\n",
- cond, proj ? "true" : "false", pos,
- block, masked_by ? masked_by->cond : NULL));
- }
- }
-
- if(get_Block_block_visited(block) < visited_nr && !saw_select_cond) {
-
- set_Block_block_visited(block, visited_nr);
-
- /* Search recursively from this cond. */
- for(i = 0, n = get_irn_arity(block); i < n; ++i) {
- ir_node *pred = get_irn_n(block, i);
-
- /*
- * If the depth is 0 (the first recursion), we set the pos to
- * the current viewed predecessor, else we adopt the position
- * as given by the caller. We also increase the depth for the
- * recursively called functions.
- */
- _find_conds(pred, visited_nr, dominator, res, pos, depth + (res != masked_by), ci);
- }
- }
- }
-}
+ ir_node* t;
+ ir_node* f;
+ (void) env;
-/**
- * A convenience function for _find_conds.
- * It sets some parameters needed for recursion to appropriate start
- * values. Always use this function.
- *
- * @param irn The node to start looking for Conds from. This might
- * be the phi node we are investigating.
- * @param conds The set to record the found Conds in.
- */
-static INLINE void find_conds(ir_node *irn, cond_info_t *ci)
-{
- int i, n;
- unsigned long visited_nr;
- ir_node *block = get_nodes_block(irn);
- ir_node *dom = get_Block_idom(block);
+ if (!is_Mux(mux)) return;
- for(i = 0, n = get_irn_arity(block); i < n; ++i) {
- ir_node *pred = get_irn_n(block, i);
+ t = get_Mux_true(mux);
+ f = get_Mux_false(mux);
- inc_irg_block_visited(current_ir_graph);
- visited_nr = get_irg_block_visited(current_ir_graph);
- set_Block_block_visited(block, visited_nr);
+ DB((dbg, LEVEL_3, "Simplify %+F T=%+F F=%+F\n", mux, t, f));
- DBG((dbg, LEVEL_2, "find conds at pred %d (%n) and idom %n\n", i, pred, dom));
- _find_conds(pred, visited_nr, dom, NULL, i, 0, ci);
- }
-}
+ if (is_Unknown(t)) {
+ DB((dbg, LEVEL_3, "Replace Mux with unknown operand by %+F\n", f));
+ exchange(mux, f);
+ return;
+ }
+ if (is_Unknown(f)) {
+ DB((dbg, LEVEL_3, "Replace Mux with unknown operand by %+F\n", t));
+ exchange(mux, t);
+ return;
+ }
-/**
- * Make the mux for a given cond.
- *
- * @param phi The phi node which shall be replaced by a mux.
- * @param dom The block where the muxes shall be placed.
- * @param cond The cond information.
- * @param info The options for createing Mux nodes.
- * @return The mux node made for this cond.
- */
-static ir_node *make_mux_on_demand(ir_node *phi, ir_node *dom, cond_t *cond,
- const opt_if_conv_info_t *info, ir_node **mux, bitset_t *positions,
- int *muxes_made, long visited_nr)
-{
- int i, can_move[2];
- ir_node *projb = get_Cond_selector(cond->cond);
- ir_node *bl = get_nodes_block(cond->cond);
- ir_node *operands[2];
- int set[2];
-
- cond->visited_nr = visited_nr;
- DBG((dbg, LEVEL_2, "%n\n", cond->cond));
- for(i = 0; i < 2; ++i) {
- cond_t *masked_by = cond->cases[i].masked_by;
- int pos = cond->cases[i].pos;
-
- operands[i] = NULL;
- set[i] = -1;
-
- /*
- * If this Cond branch is masked by another cond, make the mux
- * for that Cond first, since the Mux for this cond takes
- * it as an operand.
- */
- if(masked_by) {
- assert(pos < 0);
- DBG((dbg, LEVEL_2, "\tmasked by: %n\n", masked_by->cond));
- if(masked_by->visited_nr < visited_nr)
- operands[i] = make_mux_on_demand(phi, dom, masked_by, info, mux, positions, muxes_made, visited_nr);
- }
-
- /*
- * If this cond branch is not masked by another cond, take
- * the corresponding phi operand as an operand to the mux.
- */
- else if(pos >= 0) {
- operands[i] = get_irn_n(phi, pos);
- set[i] = pos;
- }
- }
-
- /*
- * Move the operands to the dominator block if the cond
- * made sense. Some Conds found are not suitable for making a mux
- * out of them, since one of their branches cannot be reached from
- * the phi block. In that case we do not make a mux and return NULL.
- */
- if(operands[0] && operands[1]) {
- if (operands[0] == operands[1]) {
- /* there is no gain in using mux in this case, as
- it will be optimized away. We will NOT move the
- content of the blocks either
- */
- for (i = 0; i < 2; ++i)
- if(set[i] >= 0)
- bitset_set(positions, set[i]);
-
- *mux = operands[0];
- return *mux;
- }
-
- can_move[0] = can_move_to(operands[0], bl, info);
- can_move[1] = can_move_to(operands[1], bl, info);
-
- if (can_move[0] == SUCCESS && can_move[1] == SUCCESS) {
- if (info->allow_mux(projb, operands[0], operands[1])) {
- move_to(operands[0], bl);
- move_to(operands[1], bl);
-
- /* Make the mux. */
- *mux = new_r_Mux(current_ir_graph, bl, projb,
- operands[0], operands[1], get_irn_mode(operands[0]));
-
- *muxes_made += 1;
-
- DBG((dbg, LEVEL_2, "\t%n(%n, %n, %n)[%d, %d]\n",
- *mux, projb, operands[0], operands[1], set[0], set[1]));
-
- for(i = 0; i < 2; ++i)
- if(set[i] >= 0) {
- bitset_set(positions, set[i]);
-
- /* we have done one */
- hook_if_conversion(current_ir_graph, phi, set[i], *mux, IF_RESULT_SUCCESS);
- }
- }
- else {
- hook_if_conversion(current_ir_graph, phi, set[i], *mux, IF_RESULT_DENIED);
- }
- }
- else {
- if(can_move[0] != SUCCESS)
- hook_if_conversion(current_ir_graph, phi, set[0], NULL, can_move[0]);
- if(can_move[1] != SUCCESS)
- hook_if_conversion(current_ir_graph, phi, set[1], NULL, can_move[1]);
- }
- }
- else {
- if(operands[0])
- hook_if_conversion(current_ir_graph, phi, set[0], NULL, IF_RESULT_BAD_CF);
- if(operands[1])
- hook_if_conversion(current_ir_graph, phi, set[1], NULL, IF_RESULT_BAD_CF);
- }
-
- return *mux;
+ if (is_Mux(t)) {
+ ir_graph* irg = current_ir_graph;
+ ir_node* block = get_nodes_block(mux);
+ ir_mode* mode = get_irn_mode(mux);
+ ir_node* c0 = get_Mux_sel(mux);
+ ir_node* c1 = get_Mux_sel(t);
+ ir_node* t1 = get_Mux_true(t);
+ ir_node* f1 = get_Mux_false(t);
+ if (f == f1) {
+ /* Mux(c0, Mux(c1, x, y), y) -> typical if (c0 && c1) x else y */
+ ir_node* and_ = new_r_And(irg, block, c0, c1, mode_b);
+ ir_node* new_mux = new_r_Mux(irg, block, and_, f1, t1, mode);
+ exchange(mux, new_mux);
+ } else if (f == t1) {
+ /* Mux(c0, Mux(c1, x, y), x) */
+ ir_node* not_c1 = new_r_Not(irg, block, c1, mode_b);
+ ir_node* and_ = new_r_And(irg, block, c0, not_c1, mode_b);
+ ir_node* new_mux = new_r_Mux(irg, block, and_, t1, f1, mode);
+ exchange(mux, new_mux);
+ }
+ } else if (is_Mux(f)) {
+ ir_graph* irg = current_ir_graph;
+ ir_node* block = get_nodes_block(mux);
+ ir_mode* mode = get_irn_mode(mux);
+ ir_node* c0 = get_Mux_sel(mux);
+ ir_node* c1 = get_Mux_sel(f);
+ ir_node* t1 = get_Mux_true(f);
+ ir_node* f1 = get_Mux_false(f);
+ if (t == t1) {
+ /* Mux(c0, x, Mux(c1, x, y)) -> typical if (c0 || c1) x else y */
+ ir_node* or_ = new_r_Or(irg, block, c0, c1, mode_b);
+ ir_node* new_mux = new_r_Mux(irg, block, or_, f1, t1, mode);
+ exchange(mux, new_mux);
+ } else if (t == f1) {
+ /* Mux(c0, x, Mux(c1, y, x)) */
+ ir_node* not_c1 = new_r_Not(irg, block, c1, mode_b);
+ ir_node* or_ = new_r_Or(irg, block, c0, not_c1, mode_b);
+ ir_node* new_mux = new_r_Mux(irg, block, or_, t1, f1, mode);
+ exchange(mux, new_mux);
+ }
+ }
}
-typedef struct _phi_info_t {
- struct list_head list;
- cond_info_t *cond_info;
- ir_node *irn;
-} phi_info_t;
-
-/**
- * Examine a phi node if it can be replaced by some muxes.
- * @param irn A phi node.
- * @param info Parameters for the if conversion algorithm.
- */
-static int check_out_phi(phi_info_t *phi_info, const opt_if_conv_info_t *info)
+static void optimise_muxs_1(ir_node* mux, void* env)
{
- ir_node *irn = phi_info->irn;
- ir_node *block, *nw;
- cond_info_t *cond_info = phi_info->cond_info;
- cond_t *cond;
- int i, arity;
- int muxes_made = 0;
- bitset_t *positions;
-
- block = get_nodes_block(irn);
- arity = get_irn_arity(irn);
- positions = bitset_alloca(arity);
-
- assert(is_Phi(irn));
- assert(get_irn_arity(irn) == get_irn_arity(block));
- assert(arity > 0);
-
- DBG((dbg, LEVEL_2, "phi candidate: %n\n", irn));
-
- list_for_each_entry(cond_t, cond, &cond_info->roots, list) {
- ir_node *cidom = block;
- ir_node *mux = NULL;
- cond_t *p, *head = NULL;
- long pos;
-
- bitset_clear_all(positions);
-
- DBG((dbg, LEVEL_2, "\tcond root: %n\n", cond->cond));
- /*
- * Link all conds which are in the subtree of
- * the current cond in the list together.
- */
- walk_conds(cond, link_conds, NULL, &head);
-
- cidom = block;
- for(p = head; p; p = p->link) {
- for(i = 0; i < 2; ++i) {
- int pos = p->cases[i].pos;
- if(pos != -1)
- cidom = common_idom(cidom, get_nodes_block(get_irn_n(block, pos)));
- }
- }
-
- DBG((dbg, LEVEL_2, "\tcommon idom: %n\n", cidom));
- make_mux_on_demand(irn, cidom, cond, info, &mux, positions, &muxes_made, ++cond_visited_nr);
-
- if(mux) {
- bitset_foreach(positions, pos)
- set_irn_n(irn, (int) pos, mux);
- }
- }
-
- /*
- * optimize the phi away. This can anable further runs of this
- * function. Look at _can_move. phis cannot be moved there.
- */
- nw = optimize_in_place_2(irn);
- if(nw != irn)
- exchange(irn, nw);
-
- return muxes_made;
-}
+ ir_node* t;
+ ir_node* f;
+ ir_mode* mode;
-typedef struct _cond_walk_info_t {
- struct obstack *obst;
- struct list_head cond_info_head;
- struct list_head phi_head;
-} cond_walk_info_t;
+ (void) env;
+ if (!is_Mux(mux)) return;
-static void annotate_cond_info_pre(ir_node *irn, void *data)
-{
- set_irn_link(irn, NULL);
-}
+ t = get_Mux_true(mux);
+ f = get_Mux_false(mux);
-static void annotate_cond_info_post(ir_node *irn, void *data)
-{
- cond_walk_info_t *cwi = data;
-
- /*
- * Check, if the node is a phi
- * we then compute a set of conds which are reachable from this
- * phi's block up to its dominator.
- * The set is attached to the blocks link field.
- */
- if(is_Phi(irn) && mode_is_datab(get_irn_mode(irn))) {
- ir_node *block = get_nodes_block(irn);
-
- cond_info_t *ci = get_irn_link(block);
-
- /* If the set is not yet computed, do it now. */
- if(!ci) {
- ci = obstack_alloc(cwi->obst, sizeof(*ci));
- ci->cond_set = new_set(cond_cmp, log2_ceil(get_irn_arity(block)));
- ci->first_phi = irn;
-
- INIT_LIST_HEAD(&ci->roots);
- INIT_LIST_HEAD(&ci->list);
-
- /*
- * Add this cond info to the list of all cond infos
- * in this graph. This is just done to xfree the
- * set easier afterwards (we save an irg_walk_graph).
- */
- list_add(&cwi->cond_info_head, &ci->list);
-
- DBG((dbg, LEVEL_2, "searching conds at %n\n", irn));
-
- /*
- * Fill the set with conds we find on the way from
- * the block to its dominator.
- */
- find_conds(irn, ci);
-
- /*
- * If there where no suitable conds, delete the set
- * immediately and reset the set pointer to NULL
- */
- if(set_count(ci->cond_set) == 0) {
- del_set(ci->cond_set);
- list_del(&ci->list);
- obstack_free(cwi->obst, ci);
- ci = NULL;
- }
- }
-
- else
- DBG((dbg, LEVEL_2, "conds already computed for %n (look at %n)\n", irn, ci->first_phi));
-
- set_irn_link(block, ci);
-
- if(ci) {
- phi_info_t *pi = obstack_alloc(cwi->obst, sizeof(*pi));
- pi->irn = irn;
- pi->cond_info = ci;
- INIT_LIST_HEAD(&pi->list);
- list_add(&pi->list, &cwi->phi_head);
- }
-
- }
-}
+ DB((dbg, LEVEL_3, "Simplify %+F T=%+F F=%+F\n", mux, t, f));
-static void dump_conds(cond_t *cond, void *env)
-{
- int i;
- FILE *f = env;
+ mode = get_irn_mode(mux);
- ir_fprintf(f, "node:{title:\"n%p\" label:\"%n(%d, %d)\n%n\"}\n",
- cond, cond->cond, cond->cases[0].pos, cond->cases[1].pos,
- get_nodes_block(cond->cond));
-
- for(i = 0; i < 2; ++i)
- if(cond->cases[i].masked_by)
- ir_fprintf(f, "edge:{sourcename:\"n%p\" targetname:\"n%p\" label:\"%d\"}\n",
- cond, cond->cases[i].masked_by, i);
+ if (is_Const(t) && is_Const(f) && (mode_is_int(mode))) {
+ ir_node* block = get_nodes_block(mux);
+ ir_node* c = get_Mux_sel(mux);
+ tarval* tv_t = get_Const_tarval(t);
+ tarval* tv_f = get_Const_tarval(f);
+ if (tarval_is_one(tv_t) && tarval_is_null(tv_f)) {
+ ir_node* conv = new_r_Conv(current_ir_graph, block, c, mode);
+ exchange(mux, conv);
+ } else if (tarval_is_null(tv_t) && tarval_is_one(tv_f)) {
+ ir_node* not_ = new_r_Not(current_ir_graph, block, c, mode_b);
+ ir_node* conv = new_r_Conv(current_ir_graph, block, not_, mode);
+ exchange(mux, conv);
+ }
+ }
}
-static void vcg_dump_conds(ir_graph *irg, cond_walk_info_t *cwi)
-{
- char buf[512];
- FILE *f;
-
- snprintf(buf, sizeof(buf), "%s-conds.vcg", get_entity_name(get_irg_entity(irg)));
-
- if((f = fopen(buf, "wt")) != NULL) {
- cond_info_t *ci;
- phi_info_t *phi;
- cond_t *cond;
-
- ir_fprintf(f, "graph:{\ndisplay_edge_labels:yes\n");
- list_for_each_entry(cond_info_t, ci, &cwi->cond_info_head, list) {
- ir_fprintf(f, "node:{title:\"n%p\" label:\"cond info\"}\n", ci);
- list_for_each_entry(cond_t, cond, &ci->roots, list) {
- walk_conds(cond, NULL, dump_conds, f);
- ir_fprintf(f, "edge:{sourcename:\"n%p\" targetname:\"n%p\"}\n", ci, cond);
- }
- }
-
- list_for_each_entry(phi_info_t, phi, &cwi->phi_head, list) {
- ir_fprintf(f, "node:{title:\"n%p\" label:\"%n\n%n\"}\n",
- phi->irn, phi->irn, get_nodes_block(phi->irn));
- ir_fprintf(f, "edge:{sourcename:\"n%p\" targetname:\"n%p\"}\n", phi->irn, phi->cond_info);
- }
- fprintf(f, "}\n");
- }
-}
-void opt_if_conv(ir_graph *irg, const opt_if_conv_info_t *params)
+void opt_if_conv(ir_graph *irg, const ir_settings_if_conv_t *params)
{
- int muxes_made = 0;
- struct obstack obst;
- phi_info_t *phi_info;
- cond_info_t *cond_info;
- cond_walk_info_t cwi;
+ ir_settings_if_conv_t p;
- opt_if_conv_info_t p;
+ /* get the parameters */
+ p = (params != NULL ? *params : default_info);
- if(!get_opt_if_conversion())
- return;
-
- /* get the parameters */
- if (params)
- memcpy(&p, params, sizeof(p));
- else
- memcpy(&p, &default_info, sizeof(p));
-
- if (! p.allow_mux)
- p.allow_mux = default_info.allow_mux;
+ FIRM_DBG_REGISTER(dbg, "firm.opt.ifconv");
- obstack_init(&obst);
+ DB((dbg, LEVEL_1, "Running if-conversion on %+F\n", irg));
- cwi.obst = &obst;
- INIT_LIST_HEAD(&cwi.cond_info_head);
- INIT_LIST_HEAD(&cwi.phi_head);
+ normalize_one_return(irg);
+ remove_critical_cf_edges(irg);
- /* Init the debug stuff. */
- FIRM_DBG_REGISTER(dbg, "firm.opt.ifconv");
-#if 0
- firm_dbg_set_mask(dbg, LEVEL_1|LEVEL_2|LEVEL_3);
-#endif
+ compute_cdep(irg);
+ assure_doms(irg);
- /* if-conversion works better with normalized returns */
- normalize_one_return(irg);
+ ir_reserve_resources(irg, IR_RESOURCE_BLOCK_MARK);
- /* Ensure, that the dominators are computed. */
- assure_doms(irg);
+ irg_block_walk_graph(irg, init_block_link, NULL, NULL);
+ irg_walk_graph(irg, collect_phis, NULL, NULL);
+ irg_block_walk_graph(irg, NULL, if_conv_walker, &p);
- DBG((dbg, LEVEL_1, "if conversion for irg %s(%p)\n",
- get_entity_name(get_irg_entity(irg)), irg));
+ ir_free_resources(irg, IR_RESOURCE_BLOCK_MARK);
- /*
- * Collect information about the conds pu the phis on an obstack.
- * It is important that phi nodes which are 'higher' (with a
- * lower dfs pre order) are in front of the obstack. Since they are
- * possibly turned in to muxes this can enable the optimization
- * of 'lower' ones.
- */
- irg_walk_graph(irg, annotate_cond_info_pre, annotate_cond_info_post, &cwi);
+ local_optimize_graph(irg);
-#if 0
- vcg_dump_conds(irg, &cwi);
+ irg_walk_graph(irg, NULL, optimise_muxs_0, NULL);
+#if 1
+ irg_walk_graph(irg, NULL, optimise_muxs_1, NULL);
#endif
- /* Process each suitable phi found. */
- list_for_each_entry(phi_info_t, phi_info, &cwi.phi_head, list) {
- DBG((dbg, LEVEL_2, "phi node %n\n", phi_info->irn));
- muxes_made += check_out_phi(phi_info, &p);
- }
-
- list_for_each_entry(cond_info_t, cond_info, &cwi.cond_info_head, list) {
- del_set(cond_info->cond_set);
- }
-
- DBG((dbg, LEVEL_1, "muxes made: %d\n", muxes_made));
-
- obstack_free(&obst, NULL);
+ /* TODO: graph might be changed, handle more graceful */
+ set_irg_outs_inconsistent(irg);
+ set_irg_extblk_inconsistent(irg);
+ set_irg_loopinfo_inconsistent(irg);
+ free_dom(irg);
- dump_ir_block_graph(irg, "_ifconv_hack");
+ free_cdep(irg);
}
-
-#endif
projects / libfirm / blobdiff