+/*
+ * Copyright (C) 1995-2007 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.
+ */
+
/*
* Project: libFIRM
* File name: ir/opt/ifconv.c
* Created:
* CVS-ID: $Id$
* Copyright: (c) 1998-2005 Universität Karlsruhe
- * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
*/
#if 1
#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 "irtools.h"
#include "return.h"
#include "array.h"
+#include "xmalloc.h"
// debug
#include "irdump.h"
DEBUG_ONLY(firm_dbg_module_t *dbg);
-static ir_node* walk_to_projx(ir_node* start)
+/** allow every Psi 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;
- }
+ return 1;
}
+/**
+ * Default options.
+ */
+static const opt_if_conv_info_t default_info = {
+ 0, /* doesn't matter for Psi */
+ default_allow_ifconv
+};
+
/**
* Additional block info.
*/
}
+static ir_node* walk_to_projx(ir_node* start, const ir_node* dependency)
+{
+ 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;
+}
+
+
/**
* Copies the DAG starting at node to the ith predecessor block of src_block
* -if the node isn't in the src_block, this is a nop and the node is returned
}
-/**
- * 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
*/
}
-static void if_conv_walker(ir_node* block, void* env)
+/**
+ * Remove the jth predecessors from the ith predecessor of block and add it to block
+ */
+static void split_block(ir_node* block, int i, int j)
{
+ 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;
+ 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));
+
+ NEW_ARR_A(ir_node*, ins, arity + 1);
+
+ for (phi = get_block_blockinfo(block)->phi; phi != NULL; phi = get_irn_link(phi)) {
+ ir_node* copy = copy_to(get_irn_n(phi, i), pred_block, j);
+
+ 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);
+ }
+
+ 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_blockinfo(pred_block)->phi; phi != NULL; phi = get_irn_link(phi)) {
+ 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);
+ if (new_pred_arity > 1) {
+ set_irn_in(phi, new_pred_arity, pred_ins);
+ } else {
+ exchange(phi, pred_ins[0]);
+ }
+ }
+
+ 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 {
+ exchange(pred_block, get_nodes_block(pred_ins[0]));
+ }
+}
+
+
+static void prepare_path(ir_node* block, int i, const ir_node* dependency)
+{
+ ir_node* pred = get_nodes_block(get_irn_n(block, i));
+ int pred_arity;
+ int j;
+
+ DB((dbg, LEVEL_1, "Preparing predecessor %d of %+F\n", i, block));
+
+ 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));
+
+ if (is_cdep_on(pred_pred, dependency)) {
+ prepare_path(pred, j, dependency);
+ split_block(block, i, j);
+ break;
+ }
+ }
+}
+
+
+static void if_conv_walker(ir_node* block, void* env)
+{
int arity;
int i;
+ opt_if_conv_info_t *opt_info = env;
/* 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;
- }
+ cdep* cdep;
- 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;
- }
+ pred = get_nodes_block(get_irn_n(block, i));
+ for (cdep = find_cdep(pred); cdep != NULL; cdep = cdep->next) {
+ const ir_node* dependency = cdep->node;
+ ir_node* projx0 = walk_to_projx(pred, dependency);
+ ir_node* cond;
+ int j;
- conds[0] = get_Cond_selector(cond);
+ if (projx0 == NULL) continue;
- psi_block = get_nodes_block(cond);
- phi = get_block_blockinfo(block)->phi;
- do {
- ir_node* val_i = get_irn_n(phi, i);
- ir_node* val_j = get_irn_n(phi, j);
+ cond = get_Proj_pred(projx0);
+ if (get_irn_op(cond) != op_Cond) continue;
- if (val_i == val_j) {
- psi = val_i;
- DB((dbg, LEVEL_2, "Generating no psi, because both values are equal\n"));
- } else {
- /* 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) {
- vals[0] = val_i;
- vals[1] = val_j;
+ /* We only handle boolean decisions, no switches */
+ if (get_irn_mode(get_Cond_selector(cond)) != mode_b) continue;
+
+ for (j = i + 1; j < arity; ++j) {
+ ir_node* projx1;
+ ir_node* conds[1];
+ ir_node* vals[2];
+ ir_node* psi = NULL;
+ ir_node* psi_block;
+ ir_node* phi;
+
+ pred = get_nodes_block(get_irn_n(block, j));
+
+ if (!is_cdep_on(pred, dependency)) continue;
+
+ projx1 = walk_to_projx(pred, dependency);
+
+ if (projx1 == NULL) continue;
+
+ phi = get_block_blockinfo(block)->phi;
+ if (!opt_info->allow_ifconv(get_Cond_selector(cond), phi, i, j)) continue;
+
+ DB((dbg, LEVEL_1, "Found Cond %+F with proj %+F and %+F\n",
+ cond, projx0, projx1
+ ));
+
+ prepare_path(block, i, dependency);
+ prepare_path(block, j, dependency);
+ arity = get_irn_arity(block);
+
+ conds[0] = get_Cond_selector(cond);
+
+ psi_block = get_nodes_block(cond);
+ do {
+ 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 {
- vals[0] = val_j;
- vals[1] = val_i;
+ /* 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) {
+ 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));
}
- 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);
- }
+ /* only exchange if we have a Psi */
+ if (arity == 2) {
+ exchange(phi, psi);
+ } else {
+ rewire(phi, i, j, psi);
+ }
- phi = get_irn_link(phi);
- } while (phi != NULL);
+ 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);
+ 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;
+ if (arity == 2) {
+#if 1
+ DB((dbg, LEVEL_1, "Welding block %+F and %+F\n", block, psi_block));
+ /* copy the block-info from the Psi-block to the block before merging */
+ get_block_blockinfo(psi_block)->has_pinned |= get_block_blockinfo(block)->has_pinned;
+ set_irn_link(block, get_irn_link(psi_block));
+
+ set_irn_in(block, get_irn_arity(psi_block), get_irn_in(psi_block) + 1);
+ exchange_cdep(psi_block, block);
+ exchange(psi_block, block);
+#else
+ 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);
+#endif
+ return;
+ } else {
+ rewire(block, i, j, new_r_Jmp(current_ir_graph, psi_block));
+ goto restart;
+ }
}
}
}
void opt_if_conv(ir_graph *irg, const opt_if_conv_info_t *params)
{
struct obstack obst;
+ opt_if_conv_info_t p;
- if (!get_opt_if_conversion())
+ if (! get_opt_if_conversion())
return;
+ /* get the parameters */
+ if (params)
+ memcpy(&p, params, sizeof(p));
+ else
+ memcpy(&p, &default_info, sizeof(p));
+
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);
+ irg_block_walk_graph(irg, NULL, if_conv_walker, &p);
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);
free_dom(irg);
DBG((dbg, LEVEL_1, "muxes made: %d\n", muxes_made));
obstack_free(&obst, NULL);
-
- dump_ir_block_graph(irg, "_ifconv_hack");
}
#endif