-/**
- * Author: Daniel Grund, Matthias Braun
- * Date: 20.09.2005
- * Copyright: (c) Universitaet Karlsruhe
- * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
+/*
+ * 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.
*/
-#ifdef HAVE_CONFIG_H
-#include <config.h>
-#endif
-
-#ifdef HAVE_ALLOCA_H
-#include <alloca.h>
-#endif
-#ifdef HAVE_MALLOC_H
-#include <malloc.h>
+/**
+ * @file
+ * @brief Beladys spillalgorithm.
+ * @author Daniel Grund, Matthias Braun
+ * @date 20.09.2005
+ * @version $Id$
+ */
+#ifdef HAVE_CONFIG_H
+#include "config.h"
#endif
#include "obst.h"
#include "iredges_t.h"
#include "ircons_t.h"
#include "irprintf.h"
+#include "xmalloc.h"
#include "beutil.h"
-#include "bearch.h"
+#include "bearch_t.h"
#include "bespillbelady.h"
#include "beuses_t.h"
#include "besched_t.h"
#include "bechordal_t.h"
#include "bespilloptions.h"
#include "beloopana.h"
+#include "beirg_t.h"
+#include "bemodule.h"
#define DBG_SPILL 1
#define DBG_WSETS 2
static void belady(ir_node *block, void *env);
-static loc_t to_take_or_not_to_take(belady_env_t *env, ir_node* first, ir_node *node, ir_node *block, ir_loop *loop) {
+/** Decides whether a specific node should be in the start workset or not
+ *
+ * @param env belady environment
+ * @param first
+ * @param node the node to test
+ * @param block the block of the node
+ * @param loop the loop of the node
+ */
+static loc_t to_take_or_not_to_take(belady_env_t *env, ir_node* first,
+ ir_node *node, ir_node *block,
+ ir_loop *loop)
+{
be_next_use_t next_use;
loc_t loc;
loc.time = USES_INFINITY;
+ loc.irn = node;
if (!arch_irn_consider_in_reg_alloc(env->arch, env->cls, node)) {
loc.time = USES_INFINITY;
return loc;
}
- loc.irn = node;
-
/* We have to keep nonspillable nodes in the workingset */
if(arch_irn_get_flags(env->arch, node) & arch_irn_flags_dont_spill) {
loc.time = 0;
next_use = be_get_next_use(env->uses, first, 0, node, 0);
if(USES_IS_INFINITE(next_use.time)) {
// the nodes marked as live in shouldn't be dead, so it must be a phi
+ assert(is_Phi(node));
loc.time = USES_INFINITY;
DBG((dbg, DBG_START, " %+F not taken (dead)\n", node));
- assert(is_Phi(node));
+ if(is_Phi(node)) {
+ be_spill_phi(env->senv, node);
+ }
return loc;
}
ARR_APP1(loc_t, delayed, loc);
else
ARR_APP1(loc_t, starters, loc);
- } else {
- be_spill_phi(env->senv, irn);
}
}
}
pressure = be_get_loop_pressure(env->loop_ana, env->cls, loop);
+ assert(ARR_LEN(delayed) <= (signed)pressure);
free_slots = env->n_regs - ARR_LEN(starters);
- free_pressure_slots = env->n_regs - pressure;
+ free_pressure_slots = env->n_regs - (pressure - ARR_LEN(delayed));
free_slots = MIN(free_slots, free_pressure_slots);
/* append nodes delayed due to loop structure until start set is full */
for (i = 0; i < ARR_LEN(delayed) && i < free_slots; ++i) {
DBG((dbg, DBG_START, " delayed %+F taken\n", delayed[i].irn));
ARR_APP1(loc_t, starters, delayed[i]);
+ delayed[i].irn = NULL;
+ }
+
+ /* spill all delayed phis which didn't make it into start workset */
+ for (i = ARR_LEN(delayed) - 1; i >= 0; --i) {
+ ir_node *irn = delayed[i].irn;
+ if (irn && is_Phi(irn)) {
+ DBG((dbg, DBG_START, " spilling delayed phi %+F\n", irn));
+ be_spill_phi(env->senv, irn);
+ }
}
DEL_ARR_F(delayed);
}
}
-void be_spill_belady(be_irg_t *birg, const arch_register_class_t *cls) {
+/**
+ * Do spilling for a register class on a graph using the belady heuristic.
+ * In the transformed graph, the register pressure never exceeds the number
+ * of available registers.
+ *
+ * @param birg The backend graph
+ * @param cls The register class to spill
+ */
+static void be_spill_belady(be_irg_t *birg, const arch_register_class_t *cls) {
be_spill_belady_spill_env(birg, cls, NULL);
}
void be_spill_belady_spill_env(be_irg_t *birg, const arch_register_class_t *cls, spill_env_t *spill_env) {
belady_env_t env;
ir_graph *irg = be_get_birg_irg(birg);
+ int n_regs;
- FIRM_DBG_REGISTER(dbg, "firm.be.spill.belady");
- //firm_dbg_set_mask(dbg, DBG_SPILL);
+ /* some special classes contain only ignore regs, nothing to do then */
+ n_regs = cls->n_regs - be_put_ignore_regs(birg, cls, NULL);
+ if(n_regs == 0)
+ return;
be_invalidate_liveness(birg);
be_assure_liveness(birg);
env.arch = birg->main_env->arch_env;
env.cls = cls;
env.lv = be_get_birg_liveness(birg);
- env.n_regs = env.cls->n_regs - be_put_ignore_regs(birg, cls, NULL);
+ env.n_regs = n_regs;
env.ws = new_workset(&env, &env.ob);
env.uses = be_begin_uses(irg, env.lv);
env.loop_ana = be_new_loop_pressure(birg);
};
be_register_spiller("belady", &belady_spiller);
+ FIRM_DBG_REGISTER(dbg, "firm.be.spill.belady");
}
BE_REGISTER_MODULE_CONSTRUCTOR(be_init_spillbelady);