/*
- * 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.
+ * Copyright (C) 2012 University of Karlsruhe.
*/
/**
* @file
- * @brief implementation of the spill/reload placement abstraction layer
- * @author Daniel Grund, Sebastian Hack, Matthias Braun
- * @date 29.09.2005
- * @version $Id$
+ * @brief Spill module selection; Preparation steps
+ * @author Matthias Braun
+ * @date 29.09.2005
*/
-#ifdef HAVE_CONFIG_H
#include "config.h"
-#endif
-#include <stdlib.h>
-
-#include "pset.h"
-#include "irnode_t.h"
-#include "ircons_t.h"
-#include "iredges_t.h"
-#include "irbackedge_t.h"
-#include "irprintf.h"
-#include "ident_t.h"
-#include "type_t.h"
-#include "entity_t.h"
+#include "irtools.h"
#include "debug.h"
+#include "iredges_t.h"
+#include "raw_bitset.h"
+#include "statev_t.h"
#include "irgwalk.h"
-#include "array.h"
-#include "pdeq.h"
-#include "execfreq.h"
-#include "irnodeset.h"
-#include "bearch_t.h"
-#include "belive_t.h"
-#include "besched_t.h"
#include "bespill.h"
+#include "bemodule.h"
+#include "be.h"
#include "belive_t.h"
-#include "benode_t.h"
-#include "bechordal_t.h"
-#include "bejavacoal.h"
-#include "benodesets.h"
-#include "bespilloptions.h"
-#include "bestatevent.h"
-#include "bessaconstr.h"
-#include "beirg_t.h"
+#include "beirg.h"
+#include "bearch.h"
+#include "benode.h"
+#include "besched.h"
+#include "bera.h"
#include "beintlive_t.h"
-#include "bemodule.h"
-DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
+#include "lc_opts.h"
+#include "lc_opts_enum.h"
-#define REMAT_COST_INFINITE 1000
-
-typedef struct reloader_t reloader_t;
-struct reloader_t {
- reloader_t *next;
- ir_node *reloader;
- ir_node *rematted_node;
- int remat_cost_delta; /** costs needed for rematerialization,
- compared to placing a reload */
-};
+DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
-typedef struct spill_info_t spill_info_t;
-struct spill_info_t {
- ir_node *to_spill; /**< the value that should get spilled */
- reloader_t *reloaders; /**< list of places where the value should get
- reloaded */
- ir_node *spill; /**< the spill node, or a PhiM node */
- ir_node *old_spill; /**< if we had the value of a phi spilled before but
- not the phi itself then this field contains the
- spill for the phi value */
- const arch_register_class_t *reload_cls; /** the register class in which the
- reload should be placed */
-};
+typedef struct be_pre_spill_env_t {
+ ir_graph *irg;
+ const arch_register_class_t *cls;
+} be_pre_spill_env_t;
+
+static void prepare_constr_insn(be_pre_spill_env_t *env, ir_node *node)
+{
+ const arch_register_class_t *cls = env->cls;
+ ir_node *block = get_nodes_block(node);
+ const ir_graph *irg = env->irg;
+ be_irg_t *birg = be_birg_from_irg(irg);
+ be_lv_t *lv = be_get_irg_liveness(irg);
+ unsigned *def_constr = NULL;
+ int arity = get_irn_arity(node);
+
+ /* Insert a copy for constraint inputs attached to a value which can't
+ * fulfill the constraint
+ * (typical example: stack pointer as input to copyb)
+ * TODO: This really just checks precolored registers at the moment and
+ * ignores the general case of not matching in/out constraints
+ */
+ for (int i = 0; i < arity; ++i) {
+ ir_node *op = get_irn_n(node, i);
+ const arch_register_req_t *req = arch_get_irn_register_req_in(node, i);
+ const arch_register_t *reg;
+ ir_node *copy;
-struct spill_env_t {
- const arch_env_t *arch_env;
- ir_graph *irg;
- struct obstack obst;
- be_irg_t *birg;
- int spill_cost; /**< the cost of a single spill node */
- int reload_cost; /**< the cost of a reload node */
- set *spills; /**< all spill_info_t's, which must be
- placed */
- ir_nodeset_t mem_phis; /**< set of all spilled phis. */
- ir_exec_freq *exec_freq;
-
-#ifdef FIRM_STATISTICS
- unsigned spill_count;
- unsigned reload_count;
- unsigned remat_count;
- unsigned spilled_phi_count;
-#endif
-};
+ if (req->cls != cls)
+ continue;
+ reg = arch_get_irn_register(op);
+ if (reg == NULL)
+ continue;
-/**
- * Compare two spill infos.
- */
-static
-int cmp_spillinfo(const void *x, const void *y, size_t size)
-{
- const spill_info_t *xx = x;
- const spill_info_t *yy = y;
- (void) size;
+ /* Precolored with an ignore register (which is not virtual). */
+ if (reg->type & arch_register_type_virtual ||
+ rbitset_is_set(birg->allocatable_regs, reg->global_index))
+ continue;
- return xx->to_spill != yy->to_spill;
-}
+ if (!arch_register_req_is(req, limited))
+ continue;
+ if (rbitset_is_set(req->limited, reg->index))
+ continue;
-/**
- * Returns spill info for a specific value (the value that is to be spilled)
- */
-static
-spill_info_t *get_spillinfo(const spill_env_t *env, ir_node *value)
-{
- spill_info_t info, *res;
- int hash = nodeset_hash(value);
-
- info.to_spill = value;
- res = set_find(env->spills, &info, sizeof(info), hash);
-
- if (res == NULL) {
- info.reloaders = NULL;
- info.spill = NULL;
- info.old_spill = NULL;
- info.reload_cls = NULL;
- res = set_insert(env->spills, &info, sizeof(info), hash);
+ copy = be_new_Copy(block, op);
+ stat_ev_int("constr_copy", 1);
+ sched_add_before(node, copy);
+ set_irn_n(node, i, copy);
+ DBG((dbg, LEVEL_3, "inserting ignore arg copy %+F for %+F pos %d\n",
+ copy, node, i));
}
- return res;
-}
-
-spill_env_t *be_new_spill_env(be_irg_t *birg)
-{
- const arch_env_t *arch_env = birg->main_env->arch_env;
-
- spill_env_t *env = xmalloc(sizeof(env[0]));
- env->spills = new_set(cmp_spillinfo, 1024);
- env->irg = be_get_birg_irg(birg);
- env->birg = birg;
- env->arch_env = arch_env;
- ir_nodeset_init(&env->mem_phis);
- env->spill_cost = arch_env->isa->spill_cost;
- env->reload_cost = arch_env->isa->reload_cost;
- env->exec_freq = be_get_birg_exec_freq(birg);
- obstack_init(&env->obst);
-
-#ifdef FIRM_STATISTICS
- env->spill_count = 0;
- env->reload_count = 0;
- env->remat_count = 0;
- env->spilled_phi_count = 0;
-#endif
-
- return env;
-}
-
-void be_delete_spill_env(spill_env_t *env)
-{
- del_set(env->spills);
- ir_nodeset_destroy(&env->mem_phis);
- obstack_free(&env->obst, NULL);
- free(env);
-}
-
-/*
- * ____ _ ____ _ _
- * | _ \| | __ _ ___ ___ | _ \ ___| | ___ __ _ __| |___
- * | |_) | |/ _` |/ __/ _ \ | |_) / _ \ |/ _ \ / _` |/ _` / __|
- * | __/| | (_| | (_| __/ | _ < __/ | (_) | (_| | (_| \__ \
- * |_| |_|\__,_|\___\___| |_| \_\___|_|\___/ \__,_|\__,_|___/
- *
- */
-
-void be_add_remat(spill_env_t *env, ir_node *to_spill, ir_node *before,
- ir_node *rematted_node)
-{
- spill_info_t *spill_info;
- reloader_t *reloader;
-
- spill_info = get_spillinfo(env, to_spill);
-
- /* add the remat information */
- reloader = obstack_alloc(&env->obst, sizeof(reloader[0]));
- reloader->next = spill_info->reloaders;
- reloader->reloader = before;
- reloader->rematted_node = rematted_node;
- reloader->remat_cost_delta = 0; /* We will never have a cost win over a
- reload since we're not even allowed to
- create a reload */
-
- spill_info->reloaders = reloader;
-
- DBG((dbg, LEVEL_1, "creating spillinfo for %+F, will be rematerialized before %+F\n",
- to_spill, before));
-}
-
-void be_add_reload(spill_env_t *env, ir_node *to_spill, ir_node *before,
- const arch_register_class_t *reload_cls, int allow_remat)
-{
- spill_info_t *info;
- reloader_t *rel;
-
- info = get_spillinfo(env, to_spill);
-
- if (is_Phi(to_spill)) {
- int i, arity;
+ /* insert copies for nodes that occur constrained more than once. */
+ be_foreach_use(node, cls, req, in, in_req_,
+ if (!arch_register_req_is(req, limited))
+ continue;
- /* create spillinfos for the phi arguments */
- for (i = 0, arity = get_irn_arity(to_spill); i < arity; ++i) {
- ir_node *arg = get_irn_n(to_spill, i);
- get_spillinfo(env, arg);
+ for (int i2 = i_ + 1; i2 < arity; ++i2) {
+ ir_node *in2;
+ const arch_register_req_t *req2;
+
+ req2 = arch_get_irn_register_req_in(node, i2);
+ if (req2->cls != cls)
+ continue;
+ if (!arch_register_req_is(req2, limited))
+ continue;
+
+ in2 = get_irn_n(node, i2);
+ if (in2 != in)
+ continue;
+
+ /* if the constraint is the same, no copy is necessary
+ * TODO generalise unequal but overlapping constraints */
+ if (rbitsets_equal(req->limited, req2->limited, cls->n_regs))
+ continue;
+
+ ir_node *copy = be_new_Copy(block, in);
+ stat_ev_int("constr_copy", 1);
+
+ sched_add_before(node, copy);
+ set_irn_n(node, i2, copy);
+ DBG((dbg, LEVEL_3,
+ "inserting multiple constr copy %+F for %+F pos %d\n",
+ copy, node, i2));
}
+ );
-#if 1
- /* hackery... sometimes the morgan algo spilled the value of a phi,
- * the belady algo decides later to spill the whole phi, then sees the
- * spill node and adds a reload for that spill node, problem is the
- * reload gets attach to that same spill (and is totally unnecessary)
- */
- if (info->old_spill != NULL &&
- (before == info->old_spill || value_dominates(before, info->old_spill)))
- {
- printf("spilledphi hack was needed...\n");
- before = sched_next(info->old_spill);
+ /* collect all registers occurring in out constraints. */
+ be_foreach_definition(node, cls, def, req,
+ (void)def;
+ if (!arch_register_req_is(req, limited))
+ continue;
+ if (def_constr == NULL) {
+ def_constr = rbitset_alloca(cls->n_regs);
}
-#endif
- }
-
- assert(!is_Proj(before) && !be_is_Keep(before));
-
- /* put reload into list */
- rel = obstack_alloc(&env->obst, sizeof(rel[0]));
- rel->next = info->reloaders;
- rel->reloader = before;
- rel->rematted_node = NULL;
- if(!allow_remat) {
- rel->remat_cost_delta = REMAT_COST_INFINITE;
- } else {
- rel->remat_cost_delta = 0;
- }
-
- info->reloaders = rel;
- assert(info->reload_cls == NULL || info->reload_cls == reload_cls);
- info->reload_cls = reload_cls;
-
- DBG((dbg, LEVEL_1, "creating spillinfo for %+F, will be reloaded before %+F, may%s be rematerialized\n",
- to_spill, before, allow_remat ? "" : " not"));
-}
-
-/**
- * Returns the point at which you can insert a node that should be executed
- * before block @p block when coming from pred @p pos.
- */
-static
-ir_node *get_block_insertion_point(ir_node *block, int pos)
-{
- ir_node *predblock, *last;
-
- /* simply add the reload to the beginning of the block if we only have 1
- * predecessor. We don't need to check for phis as there can't be any in a
- * block with only 1 pred. */
- if(get_Block_n_cfgpreds(block) == 1) {
- assert(!is_Phi(sched_first(block)));
- return sched_first(block);
- }
-
- /* We have to reload the value in pred-block */
- predblock = get_Block_cfgpred_block(block, pos);
- last = sched_last(predblock);
-
- /* we might have projs and keepanys behind the jump... */
- while(is_Proj(last) || be_is_Keep(last)) {
- last = sched_prev(last);
- assert(!sched_is_end(last));
- }
-
- if(!is_cfop(last)) {
- last = sched_next(last);
- /* last node must be a cfop, only exception is the start block */
- assert(last == get_irg_start_block(get_irn_irg(block)));
- }
-
- /* add the reload before the (cond-)jump */
- return last;
-}
-
-void be_add_reload_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block,
- int pos, const arch_register_class_t *reload_cls,
- int allow_remat)
-{
- ir_node *before = get_block_insertion_point(block, pos);
- be_add_reload(env, to_spill, before, reload_cls, allow_remat);
-}
-
-void be_spill_phi(spill_env_t *env, ir_node *node)
-{
- spill_info_t* spill;
- int i, arity;
-
- assert(is_Phi(node));
-
- ir_nodeset_insert(&env->mem_phis, node);
-
- /* create spillinfos for the phi arguments */
- spill = get_spillinfo(env, node);
- for(i = 0, arity = get_irn_arity(node); i < arity; ++i) {
- ir_node *arg = get_irn_n(node, i);
- get_spillinfo(env, arg);
- }
-
- /* if we had a spill for the phi value before, then remove this spill from
- * schedule, as we will remove it in the insert spill/reload phase
- */
- if(spill->spill != NULL && !is_Phi(spill->spill)) {
- assert(spill->old_spill == NULL);
- spill->old_spill = spill->spill;
- spill->spill = NULL;
- }
-}
-
-/*
- * ____ _ ____ _ _ _
- * / ___|_ __ ___ __ _| |_ ___ / ___| _ __ (_) | |___
- * | | | '__/ _ \/ _` | __/ _ \ \___ \| '_ \| | | / __|
- * | |___| | | __/ (_| | || __/ ___) | |_) | | | \__ \
- * \____|_| \___|\__,_|\__\___| |____/| .__/|_|_|_|___/
- * |_|
- */
-
-/**
- * Schedules a node after an instruction. That is the place after all projs and
- * phis that are scheduled after the instruction. This function also skips phi
- * nodes at the beginning of a block
- */
-static
-void sched_add_after_insn(ir_node *sched_after, ir_node *node)
-{
- ir_node *next = sched_next(sched_after);
- while(is_Proj(next) || is_Phi(next) || be_is_Keep(next)) {
- next = sched_next(next);
- }
- assert(next != NULL);
-
- if(sched_is_end(next)) {
- sched_add_after(sched_last(get_nodes_block(sched_after)), node);
- } else {
- sched_add_before(next, node);
- }
-}
-
-/**
- * Creates a spill.
- *
- * @param senv the spill environment
- * @param irn the node that should be spilled
- * @param ctx_irn an user of the spilled node
- *
- * @return a be_Spill node
- */
-static
-void spill_irn(spill_env_t *env, spill_info_t *spillinfo)
-{
- optimization_state_t opt;
- ir_node *to_spill = spillinfo->to_spill;
-
- DBG((dbg, LEVEL_1, "spilling %+F ... ", to_spill));
-
- /* Trying to spill an already spilled value, no need for a new spill
- * node then, we can simply connect to the same one for this reload
- *
- * Normally reloads get simply rematerialized instead of spilled again; this
- * can happen annyway when the reload is the pred of a phi to spill)
- */
- if (be_is_Reload(to_spill)) {
- spillinfo->spill = get_irn_n(to_spill, be_pos_Reload_mem);
- DB((dbg, LEVEL_1, "skip reload, using existing spill %+F\n", spillinfo->spill));
- return;
- }
-
- assert(!(arch_irn_is(env->arch_env, to_spill, dont_spill)
- && "Attempt to spill a node marked 'dont_spill'"));
+ rbitset_or(def_constr, req->limited, cls->n_regs);
+ );
- /* some backends have virtual noreg/unknown nodes that are not scheduled */
- if(!sched_is_scheduled(to_spill)) {
- spillinfo->spill = new_NoMem();
+ /* no output constraints => we're good */
+ if (def_constr == NULL) {
return;
}
-
/*
- * We switch on optimizations here to get CSE. This is needed as the STA
- * backends has some extra spill phases and we want to make use of those
- * spills instead of creating new ones.
+ * insert copies for all constrained arguments living through the node
+ * and being constrained to a register which also occurs in out constraints.
*/
- save_optimization_state(&opt);
- set_optimize(1);
- spillinfo->spill = be_spill(env->arch_env, to_spill);
- restore_optimization_state(&opt);
- if (! sched_is_scheduled(spillinfo->spill)) {
- DB((dbg, LEVEL_1, "add spill %+F after %+F\n", spillinfo->spill, to_spill));
-#ifdef FIRM_STATISTICS
- env->spill_count++;
-#endif
- sched_add_after_insn(to_spill, spillinfo->spill);
- } else {
- DB((dbg, LEVEL_1, "re-using spill %+F after %+F\n", spillinfo->spill, to_spill));
- }
-}
-
-static
-void spill_node(spill_env_t *env, spill_info_t *spillinfo);
-
-/**
- * If the first usage of a Phi result would be out of memory
- * there is no sense in allocating a register for it.
- * Thus we spill it and all its operands to the same spill slot.
- * Therefore the phi/dataB becomes a phi/Memory
- *
- * @param senv the spill environment
- * @param phi the Phi node that should be spilled
- * @param ctx_irn an user of the spilled node
- */
-static
-void spill_phi(spill_env_t *env, spill_info_t *spillinfo)
-{
- ir_node *phi = spillinfo->to_spill;
- int i;
- int arity = get_irn_arity(phi);
- ir_node *block = get_nodes_block(phi);
- ir_node **ins;
-
- assert(is_Phi(phi));
-
- DBG((dbg, LEVEL_1, "spilling Phi %+F:\n", phi));
- /* build a new PhiM */
- ins = alloca(sizeof(ir_node*) * arity);
- for(i = 0; i < arity; ++i) {
- ins[i] = get_irg_bad(env->irg);
- }
- spillinfo->spill = new_r_Phi(env->irg, block, arity, ins, mode_M);
-#ifdef FIRM_STATISTICS
- env->spilled_phi_count++;
-#endif
-
- for(i = 0; i < arity; ++i) {
- ir_node *arg = get_irn_n(phi, i);
- spill_info_t *arg_info = get_spillinfo(env, arg);
-
- spill_node(env, arg_info);
-
- set_irn_n(spillinfo->spill, i, arg_info->spill);
- }
- DBG((dbg, LEVEL_1, "... done spilling Phi %+F, created PhiM %+F\n", phi, spillinfo->spill));
-
- /* rewire reloads from old_spill to phi */
- if (spillinfo->old_spill != NULL) {
- const ir_edge_t *edge, *next;
- ir_node *old_spill = spillinfo->old_spill;
+ unsigned *const tmp = rbitset_alloca(cls->n_regs);
+ be_foreach_use(node, cls, req, in, in_req_,
+ /* Check, if
+ * 1) the operand is constrained.
+ * 2) lives through the node.
+ * 3) is constrained to a register occurring in out constraints.
+ */
+ if (!arch_register_req_is(req, limited))
+ continue;
+ if (!be_values_interfere(lv, node, in))
+ continue;
- DBG((dbg, LEVEL_1, "old spill found, rewiring reloads:\n"));
+ rbitset_copy(tmp, req->limited, cls->n_regs);
+ rbitset_and(tmp, def_constr, cls->n_regs);
- foreach_out_edge_safe(old_spill, edge, next) {
- ir_node *reload = get_edge_src_irn(edge);
- int pos = get_edge_src_pos(edge);
+ if (rbitset_is_empty(tmp, cls->n_regs))
+ continue;
- DBG((dbg, LEVEL_1, "\tset input %d of %+F to %+F\n", pos, reload, spillinfo->spill));
+ /*
+ * only create the copy if the operand is no copy.
+ * this is necessary since the assure constraints phase inserts
+ * Copies and Keeps for operands which must be different from the
+ * results. Additional copies here would destroy this.
+ */
+ if (be_is_Copy(in))
+ continue;
- assert(be_is_Reload(reload) || is_Phi(reload));
- set_irn_n(reload, pos, spillinfo->spill);
- }
- DBG((dbg, LEVEL_1, "\tset input of %+F to BAD\n", old_spill));
- set_irn_n(old_spill, be_pos_Spill_val, new_Bad());
- /* sched_remove(old_spill); */
- spillinfo->old_spill = NULL;
- }
+ ir_node *copy = be_new_Copy(block, in);
+ sched_add_before(node, copy);
+ set_irn_n(node, i_, copy);
+ DBG((dbg, LEVEL_3, "inserting constr copy %+F for %+F pos %d\n",
+ copy, node, i_));
+ be_liveness_update(lv, in);
+ );
}
-/**
- * Spill a node.
- *
- * @param senv the spill environment
- * @param to_spill the node that should be spilled
- */
-static
-void spill_node(spill_env_t *env, spill_info_t *spillinfo)
+static void pre_spill_prepare_constr_walker(ir_node *block, void *data)
{
- ir_node *to_spill;
-
- /* the node should be tagged for spilling already... */
- if(spillinfo->spill != NULL)
- return;
-
- to_spill = spillinfo->to_spill;
-
- if (is_Phi(to_spill) && ir_nodeset_contains(&env->mem_phis, to_spill)) {
- spill_phi(env, spillinfo);
- } else {
- spill_irn(env, spillinfo);
+ be_pre_spill_env_t *env = (be_pre_spill_env_t*)data;
+ sched_foreach(block, node) {
+ prepare_constr_insn(env, node);
}
}
-/*
- *
- * ____ _ _ _ _
- * | _ \ ___ _ __ ___ __ _| |_ ___ _ __(_) __ _| (_)_______
- * | |_) / _ \ '_ ` _ \ / _` | __/ _ \ '__| |/ _` | | |_ / _ \
- * | _ < __/ | | | | | (_| | || __/ | | | (_| | | |/ / __/
- * |_| \_\___|_| |_| |_|\__,_|\__\___|_| |_|\__,_|_|_/___\___|
- *
- */
-
-/**
- * Tests whether value @p arg is available before node @p reloader
- * @returns 1 if value is available, 0 otherwise
- */
-static
-int is_value_available(spill_env_t *env, ir_node *arg, ir_node *reloader)
+void be_pre_spill_prepare_constr(ir_graph *irg,
+ const arch_register_class_t *cls)
{
- if(is_Unknown(arg) || arg == new_NoMem())
- return 1;
+ be_pre_spill_env_t env;
+ memset(&env, 0, sizeof(env));
+ env.irg = irg;
+ env.cls = cls;
- if(be_is_Spill(arg))
- return 1;
+ be_assure_live_sets(irg);
- if(arg == get_irg_frame(env->irg))
- return 1;
-
- /* hack for now (happens when command should be inserted at end of block) */
- if(is_Block(reloader)) {
- return 0;
- }
-
- /*
- * Ignore registers are always available
- */
- if(arch_irn_is(env->arch_env, arg, ignore)) {
- return 1;
- }
-
- /* the following test does not work while spilling,
- * because the liveness info is not adapted yet to the effects of the
- * additional spills/reloads.
- */
-#if 0
- /* we want to remat before the insn reloader
- * thus an arguments is alive if
- * - it interferes with the reloaders result
- * - or it is (last-) used by reloader itself
- */
- if (values_interfere(env->birg->lv, reloader, arg)) {
- return 1;
- }
-
- arity = get_irn_arity(reloader);
- for (i = 0; i < arity; ++i) {
- ir_node *rel_arg = get_irn_n(reloader, i);
- if (rel_arg == arg)
- return 1;
- }
-#endif
-
- return 0;
+ irg_block_walk_graph(irg, pre_spill_prepare_constr_walker, NULL, &env);
}
-/**
- * Checks whether the node can principally be rematerialized
- */
-static
-int is_remat_node(spill_env_t *env, ir_node *node)
-{
- const arch_env_t *arch_env = env->arch_env;
-
- assert(!be_is_Spill(node));
- if(arch_irn_is(arch_env, node, rematerializable))
- return 1;
- return 0;
-}
+int be_coalesce_spill_slots = 1;
+int be_do_remats = 1;
-/**
- * Check if a node is rematerializable. This tests for the following conditions:
- *
- * - The node itself is rematerializable
- * - All arguments of the node are available or also rematerialisable
- * - The costs for the rematerialisation operation is less or equal a limit
- *
- * Returns the costs needed for rematerialisation or something
- * >= REMAT_COST_INFINITE if remat is not possible.
- */
-static
-int check_remat_conditions_costs(spill_env_t *env, ir_node *spilled,
- ir_node *reloader, int parentcosts)
-{
- int i, arity;
- int argremats;
- int costs = 0;
-
- if(!is_remat_node(env, spilled))
- return REMAT_COST_INFINITE;
-
- if(be_is_Reload(spilled)) {
- costs += 2;
- } else {
- costs += arch_get_op_estimated_cost(env->arch_env, spilled);
- }
- if(parentcosts + costs >= env->reload_cost + env->spill_cost) {
- return REMAT_COST_INFINITE;
- }
-
- argremats = 0;
- for(i = 0, arity = get_irn_arity(spilled); i < arity; ++i) {
- ir_node *arg = get_irn_n(spilled, i);
-
- if(is_value_available(env, arg, reloader))
- continue;
-
- /* we have to rematerialize the argument as well */
- if(argremats >= 1) {
- /* we only support rematerializing 1 argument at the moment,
- * so that we don't have to care about register pressure
- */
- return REMAT_COST_INFINITE;
- }
- argremats++;
-
- costs += check_remat_conditions_costs(env, arg, reloader, parentcosts + costs);
- if(parentcosts + costs >= env->reload_cost + env->spill_cost)
- return REMAT_COST_INFINITE;
- }
-
- return costs;
-}
-
-/**
- * Re-materialize a node.
- *
- * @param senv the spill environment
- * @param spilled the node that was spilled
- * @param reloader a irn that requires a reload
- */
-static
-ir_node *do_remat(spill_env_t *env, ir_node *spilled, ir_node *reloader)
-{
- int i, arity;
- ir_node *res;
- ir_node *bl;
- ir_node **ins;
-
- if(is_Block(reloader)) {
- bl = reloader;
- } else {
- bl = get_nodes_block(reloader);
- }
-
- ins = alloca(get_irn_arity(spilled) * sizeof(ins[0]));
- for(i = 0, arity = get_irn_arity(spilled); i < arity; ++i) {
- ir_node *arg = get_irn_n(spilled, i);
-
- if(is_value_available(env, arg, reloader)) {
- ins[i] = arg;
- } else {
- ins[i] = do_remat(env, arg, reloader);
-#ifdef FIRM_STATISTICS
- /* don't count the recursive call as remat */
- env->remat_count--;
-#endif
- }
- }
-
- /* create a copy of the node */
- res = new_ir_node(get_irn_dbg_info(spilled), env->irg, bl,
- get_irn_op(spilled), get_irn_mode(spilled),
- get_irn_arity(spilled), ins);
- copy_node_attr(spilled, res);
- new_backedge_info(res);
-
- DBG((dbg, LEVEL_1, "Insert remat %+F of %+F before reloader %+F\n", res, spilled, reloader));
-
-#ifdef SCHEDULE_PROJS
- /* insert in schedule */
- sched_reset(res);
- sched_add_before(reloader, res);
-#ifdef FIRM_STATISTICS
- if (! is_Proj(res))
- env->remat_count++;
-#endif
-#else
- if (! is_Proj(res)) {
- /* insert in schedule */
- sched_reset(res);
- sched_add_before(reloader, res);
-#ifdef FIRM_STATISTICS
- env->remat_count++;
-#endif
- }
-#endif /* SCHEDULE_PROJS */
+static const lc_opt_table_entry_t be_spill_options[] = {
+ LC_OPT_ENT_BOOL ("coalesce_slots", "coalesce the spill slots", &be_coalesce_spill_slots),
+ LC_OPT_ENT_BOOL ("remat", "try to rematerialize values instead of reloading", &be_do_remats),
+ LC_OPT_LAST
+};
- return res;
-}
+static be_module_list_entry_t *spillers = NULL;
+static const be_spiller_t *selected_spiller = NULL;
-double be_get_spill_costs(spill_env_t *env, ir_node *to_spill, ir_node *after)
+void be_register_spiller(const char *name, be_spiller_t *spiller)
{
- ir_node *block = get_nodes_block(after);
- double freq = get_block_execfreq(env->exec_freq, block);
- (void) to_spill;
-
- return env->spill_cost * freq;
+ if (selected_spiller == NULL)
+ selected_spiller = spiller;
+ be_add_module_to_list(&spillers, name, spiller);
}
-double be_get_reload_costs(spill_env_t *env, ir_node *to_spill, ir_node *before)
+void be_do_spill(ir_graph *irg, const arch_register_class_t *cls)
{
- ir_node *block = get_nodes_block(before);
- double freq = get_block_execfreq(env->exec_freq, block);
-
- if(be_do_remats) {
- /* is the node rematerializable? */
- int costs = check_remat_conditions_costs(env, to_spill, before, 0);
- if(costs < env->reload_cost)
- return costs * freq;
- }
+ assert(selected_spiller != NULL);
- return env->reload_cost * freq;
+ selected_spiller->spill(irg, cls);
}
-double be_get_reload_costs_on_edge(spill_env_t *env, ir_node *to_spill,
- ir_node *block, int pos)
+BE_REGISTER_MODULE_CONSTRUCTOR(be_init_spilloptions)
+void be_init_spilloptions(void)
{
- ir_node *before = get_block_insertion_point(block, pos);
- return be_get_reload_costs(env, to_spill, before);
-}
+ lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be");
+ lc_opt_entry_t *spill_grp = lc_opt_get_grp(be_grp, "spill");
-/*
- * ___ _ ____ _ _
- * |_ _|_ __ ___ ___ _ __| |_ | _ \ ___| | ___ __ _ __| |___
- * | || '_ \/ __|/ _ \ '__| __| | |_) / _ \ |/ _ \ / _` |/ _` / __|
- * | || | | \__ \ __/ | | |_ | _ < __/ | (_) | (_| | (_| \__ \
- * |___|_| |_|___/\___|_| \__| |_| \_\___|_|\___/ \__,_|\__,_|___/
- *
- */
-
-void be_insert_spills_reloads(spill_env_t *env)
-{
- const arch_env_t *arch_env = env->arch_env;
- const ir_exec_freq *exec_freq = env->exec_freq;
- spill_info_t *si;
- ir_nodeset_iterator_t iter;
- ir_node *node;
-
- /* create all phi-ms first, this is needed so, that phis, hanging on
- spilled phis work correctly */
- foreach_ir_nodeset(&env->mem_phis, node, iter) {
- spill_info_t *info = get_spillinfo(env, node);
- spill_node(env, info);
- }
-
- /* process each spilled node */
- for (si = set_first(env->spills); si; si = set_next(env->spills)) {
- reloader_t *rld;
- ir_node *to_spill = si->to_spill;
- ir_mode *mode = get_irn_mode(to_spill);
- ir_node **copies = NEW_ARR_F(ir_node*, 0);
- double all_remat_costs = 0; /** costs when we would remat all nodes */
- int force_remat = 0;
-
- DBG((dbg, LEVEL_1, "\nhandling all reloaders of %+F:\n", to_spill));
-
- /* determine possibility of rematerialisations */
- if(be_do_remats) {
- for (rld = si->reloaders; rld != NULL; rld = rld->next) {
- double freq;
- int remat_cost;
- int remat_cost_delta;
- ir_node *block;
- ir_node *reloader = rld->reloader;
-
- if(rld->rematted_node != NULL) {
- DBG((dbg, LEVEL_2, "\tforced remat %+F before %+F\n",
- rld->rematted_node, reloader));
- continue;
- }
- if(rld->remat_cost_delta >= REMAT_COST_INFINITE) {
- DBG((dbg, LEVEL_2, "\treload before %+F is forbidden\n",
- reloader));
- all_remat_costs = REMAT_COST_INFINITE;
- continue;
- }
-
- remat_cost = check_remat_conditions_costs(env, to_spill,
- reloader, 0);
- if(remat_cost >= REMAT_COST_INFINITE) {
- DBG((dbg, LEVEL_2, "\tremat before %+F not possible\n",
- reloader));
- rld->remat_cost_delta = REMAT_COST_INFINITE;
- all_remat_costs = REMAT_COST_INFINITE;
- continue;
- }
-
- remat_cost_delta = remat_cost - env->reload_cost;
- rld->remat_cost_delta = remat_cost_delta;
- block = get_nodes_block(reloader);
- freq = get_block_execfreq(exec_freq, block);
- all_remat_costs += remat_cost_delta * freq;
- DBG((dbg, LEVEL_2, "\tremat costs delta before %+F: "
- "%d (rel %f)\n", reloader, remat_cost_delta,
- remat_cost_delta * freq));
- }
- if(all_remat_costs < REMAT_COST_INFINITE) {
- ir_node *block = get_nodes_block(to_spill);
- double freq = get_block_execfreq(exec_freq, block);
- /* we don't need the costs for the spill if we can remat
- all reloaders */
- all_remat_costs -= env->spill_cost * freq;
-
- DBG((dbg, LEVEL_2, "\tspill costs %d (rel %f)\n",
- env->spill_cost, env->spill_cost * freq));
- }
-
- if(all_remat_costs < 0) {
- DBG((dbg, LEVEL_1, "\nforcing remats of all reloaders (%f)\n",
- all_remat_costs));
- force_remat = 1;
- }
- }
+ lc_opt_add_table(spill_grp, be_spill_options);
+ be_add_module_list_opt(be_grp, "spiller", "spill algorithm",
+ &spillers, (void**) &selected_spiller);
- /* go through all reloads for this spill */
- for (rld = si->reloaders; rld != NULL; rld = rld->next) {
- ir_node *copy; /* a reload is a "copy" of the original value */
-
- if (rld->rematted_node != NULL) {
- copy = rld->rematted_node;
- sched_add_before(rld->reloader, copy);
- } else if (be_do_remats &&
- (force_remat || rld->remat_cost_delta < 0)) {
- copy = do_remat(env, to_spill, rld->reloader);
- } else {
- /* make sure we have a spill */
- if (si->spill == NULL) {
- spill_node(env, si);
- }
-
- /* create a reload */
- copy = be_reload(arch_env, si->reload_cls, rld->reloader, mode,
- si->spill);
-#ifdef FIRM_STATISTICS
- env->reload_count++;
-#endif
- }
-
- DBG((dbg, LEVEL_1, " %+F of %+F before %+F\n",
- copy, to_spill, rld->reloader));
- ARR_APP1(ir_node*, copies, copy);
- }
-
- /* if we had any reloads or remats, then we need to reconstruct the
- * SSA form for the spilled value */
- if (ARR_LEN(copies) > 0) {
- be_ssa_construction_env_t senv;
- /* be_lv_t *lv = be_get_birg_liveness(env->birg); */
-
- be_ssa_construction_init(&senv, env->birg);
- be_ssa_construction_add_copy(&senv, to_spill);
- be_ssa_construction_add_copies(&senv, copies, ARR_LEN(copies));
- be_ssa_construction_fix_users(&senv, to_spill);
-
-#if 0
- /* no need to enable this as long as we invalidate liveness
- after this function... */
- be_ssa_construction_update_liveness_phis(&senv);
- be_liveness_update(to_spill);
- len = ARR_LEN(copies);
- for(i = 0; i < len; ++i) {
- be_liveness_update(lv, copies[i]);
- }
-#endif
- be_ssa_construction_destroy(&senv);
- }
-
- DEL_ARR_F(copies);
- si->reloaders = NULL;
- }
-
- stat_ev_dbl("spill_spills", env->spill_count);
- stat_ev_dbl("spill_reloads", env->reload_count);
- stat_ev_dbl("spill_remats", env->remat_count);
- stat_ev_dbl("spill_spilled_phis", env->spilled_phi_count);
-
- /* Matze: In theory be_ssa_construction should take care of the liveness...
- * try to disable this again in the future */
- be_liveness_invalidate(env->birg->lv);
-
- be_remove_dead_nodes_from_schedule(env->birg);
-}
-
-void be_init_spill(void)
-{
- FIRM_DBG_REGISTER(dbg, "firm.be.spill");
+ FIRM_DBG_REGISTER(dbg, "firm.be.spillprepare");
}
-
-BE_REGISTER_MODULE_CONSTRUCTOR(be_init_spill);
projects / libfirm / blobdiff