+++ /dev/null
-/*
- * 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 Statistics for Firm, register pressure estimation.
- * @author Michael Beck
- * @version $Id$
- */
-#include "config.h"
-#include "irgwalk.h"
-#include "irbitset.h"
-#include "irtools.h"
-#include "array_t.h"
-#include "irnode_t.h"
-
-typedef struct block_entry_t block_entry_t;
-typedef struct environment_t environment_t;
-
-/** A Block entry. */
-struct block_entry_t {
- ir_node **live_ins; /**< The array of live ins. */
- ir_node **live_outs; /**< The array of live outs. */
- ir_node *block; /**< The associated block. */
- block_entry_t *next; /**< Links to the next block entry. */
-};
-
-struct environment_t {
- struct obstack obst;
- block_entry_t *entries; /**< List of all allocated block entries. */
- bitset_t *visited; /**< a Bitset to mark visited nodes */
-};
-
-static environment_t *env;
-
-/**
- * Get the block entry or allocate one if not yet assigned.
- */
-static block_entry_t *get_block_entry(ir_node *block)
-{
- block_entry_t *entry = (block_entry_t*)get_irn_link(block);
-
- if (entry == NULL) {
- entry = OALLOC(&env->obst, block_entry_t);
-
- entry->live_ins = NEW_ARR_F(ir_node *, 0);
- entry->live_outs = NEW_ARR_F(ir_node *, 0);
-
- entry->next = env->entries;
- env->entries = entry;
- }
- return entry;
-}
-
-static void add_entry(ir_node ***arr, ir_node *irn)
-{
- ir_node **list = *arr;
- size_t i;
-
- for (i = ARR_LEN(list); i > 0;) {
- --i;
- if (list[i] == irn) {
- /* already there */
- return;
- }
- }
- ARR_APP1(ir_node *, *arr, irn);
-}
-
-static void add_live_in(ir_node *block, ir_node *irn)
-{
- block_entry_t *entry = get_block_entry(block);
-
- add_entry(&entry->live_ins, irn);
-}
-
-static void add_live_out(ir_node *block, ir_node *irn)
-{
- block_entry_t *entry = get_block_entry(block);
-
- add_entry(&entry->live_outs, irn);
-}
-
-/**
- * Mark a node (value) live out at a certain block. Do this also
- * transitively, i.e. if the block is not the block of the value's
- * definition, all predecessors are also marked live.
- *
- * @param def The node (value).
- * @param block The block to mark the value live out of.
- */
-static void live_end_at_block(ir_node *def, ir_node *block)
-{
- add_live_out(block, def);
-
- if (is_irn_constlike(def)) {
- /* do NOT follow Constants further, assume they are
- part of instruction or can easily
- be rematerialized */
- return;
- }
-
- if (! bitset_contains_irn(env->visited, block)) {
- bitset_add_irn(env->visited, block);
-
- /*
- * If this block is not the definition block, we have to go up
- * further.
- */
- if (get_nodes_block(def) != block) {
- int i;
-
- add_live_in(block, def);
-
- for (i = get_Block_n_cfgpreds(block) - 1; i >= 0; --i)
- live_end_at_block(def, get_Block_cfgpred_block(block, i));
- }
- }
-}
-
-/**
- * Walker: finds live-outs and calculate live-ins from that.
- */
-static void find_live_outs(ir_node *irn, void *ctx)
-{
- ir_mode *mode = get_irn_mode(irn);
- ir_node *block, *use_block;
- int i;
-
- (void)ctx;
-
- /* only data nodes */
- if (! mode_is_datab(mode))
- return;
-
- block = get_nodes_block(irn);
-
- for (i = get_irn_arity(irn) - 1; i >= 0; --i) {
- ir_node *pred = get_irn_n(irn, i);
-
- if (mode_is_datab(get_irn_mode(pred))) {
- ir_node *def_block = get_nodes_block(pred);
-
- if (is_Phi(irn)) {
- use_block = get_Block_cfgpred_block(block, i);
-
- /* even if pred is a Const, it MUST be
- in a register on block output */
- bitset_clear_all(env->visited);
- live_end_at_block(pred, use_block);
-
- /* The Block has only one live in, the Phi itself */
- add_live_in(block, irn);
- }
- else if (def_block != use_block) {
- /* pred is a live in of our block */
- if (is_irn_constlike(pred)) {
- /* ignore Constants, assume they are
- part of instruction or can easily
- be rematerialized */
- continue;
- }
-
- use_block = block;
- add_live_in(use_block, pred);
-
- bitset_clear_all(env->visited);
- for (i = get_Block_n_cfgpreds(use_block); i >= 0; --i) {
- ir_node *pred_block = get_Block_cfgpred_block(use_block, i);
- live_end_at_block(irn, pred_block);
- }
- }
- }
- }
-}
-
-/**
- * Calculate the live-in and live out of blocks for datab nodes.
- * Use it to estimate register pressure.
- */
-void stat_liveness(ir_graph *irg)
-{
- environment_t genv;
- block_entry_t *p;
-
- env = &genv;
-
- obstack_init(&env->obst);
- env->entries = NULL;
- env->visited = bitset_obstack_alloc(&env->obst, get_irg_last_idx(irg));
-
- irg_block_walk_graph(irg, NULL, firm_clear_link, NULL);
- irg_walk_graph(irg, NULL, find_live_outs, NULL);
-
- for (p = env->entries; p != NULL; p = p->next) {
- DEL_ARR_F(p->live_ins);
- DEL_ARR_F(p->live_outs);
- }
- obstack_free(&env->obst, NULL);
- env = NULL;
-}
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