-/**
- * Author: Daniel Grund, Sebastian Hack
+/*
+ * Author: Daniel Grund, Sebastian Hack, Matthias Braun
* Date: 29.09.2005
* Copyright: (c) Universitaet Karlsruhe
* Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE.
+ * CVS-Id: $Id$
*/
+#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 "debug.h"
-
-#include "besched.h"
+#include "irgwalk.h"
+#include "array.h"
+#include "pdeq.h"
+#include "unionfind.h"
+#include "execfreq.h"
+
+#include "belive_t.h"
+#include "besched_t.h"
#include "bespill.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"
+
+// only rematerialise when costs are less than REMAT_COST_LIMIT
+// TODO determine a good value here...
+#define REMAT_COST_LIMIT 10
typedef struct _reloader_t reloader_t;
-typedef struct _spill_info_t spill_info_t;
struct _reloader_t {
reloader_t *next;
- ir_node *reloader;
+ ir_node *reloader;
+ ir_node *rematted_node;
+ int allow_remat; /**< the node may be rematted instead of reloaded if global remat option is on */
};
-struct _spill_info_t {
+typedef struct _spill_info_t {
+ /** the value that should get spilled */
ir_node *spilled_node;
+ /** list of places where the value should get reloaded */
reloader_t *reloaders;
-};
-typedef struct _spill_ctx_t {
- ir_node *spilled; /**< The spilled node. */
- ir_node *user; /**< The node this spill is for. */
- ir_node *spill; /**< The spill itself. */
-} spill_ctx_t;
+ /** the spill node, or a PhiM node */
+ ir_node *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 */
+ ir_node *old_spill;
+
+ /** the register class in which the reload should be placed */
+ const arch_register_class_t *reload_cls;
+} spill_info_t;
struct _spill_env_t {
- firm_dbg_module_t *dbg;
- const arch_register_class_t *cls;
- const be_chordal_env_t *chordal_env;
+ const arch_env_t *arch_env;
+ ir_graph *irg;
struct obstack obst;
- set *spill_ctxs;
- set *spills; /**< all spill_info_t's, which must be placed */
- pset *mem_phis; /**< set of all special spilled phis. allocated and freed seperately */
- decide_irn_t is_mem_phi; /**< callback func to decide if a phi needs special spilling */
- void *data; /**< data passed to all callbacks */
-};
+ 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 */
+ pset *mem_phis; /**< set of all special spilled phis. allocated and freed separately */
-static int cmp_spillctx(const void *a, const void *b, size_t n) {
- const spill_ctx_t *p = a;
- const spill_ctx_t *q = b;
- return !(p->user == q->user && p->spilled == q->spilled);
-}
+ DEBUG_ONLY(firm_dbg_module_t *dbg;)
+};
+/**
+ * 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;
- return ! (xx->spilled_node == yy->spilled_node);
+ return xx->spilled_node != yy->spilled_node;
+}
+
+/**
+ * Returns spill info for a specific value (returns NULL if the info doesn't
+ * exist yet)
+ */
+static spill_info_t *find_spillinfo(const spill_env_t *env, ir_node *value) {
+ spill_info_t info;
+ int hash = nodeset_hash(value);
+
+ info.spilled_node = value;
+
+ return set_find(env->spills, &info, sizeof(info), hash);
+}
+
+/**
+ * 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.spilled_node = 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);
+ }
+
+ return res;
}
-spill_env_t *be_new_spill_env(firm_dbg_module_t *dbg,
- const be_chordal_env_t *chordal_env,
- decide_irn_t is_mem_phi, void *data) {
-
- spill_env_t *env = malloc(sizeof(env[0]));
- env->spill_ctxs = new_set(cmp_spillctx, 1024);
- env->spills = new_set(cmp_spillinfo, 1024);
- env->cls = chordal_env->cls;
- env->dbg = dbg;
- env->is_mem_phi = is_mem_phi;
- env->data = data;
- env->chordal_env = chordal_env;
+DEBUG_ONLY(
+/* Sets the debug module of a spill environment. */
+void be_set_spill_env_dbg_module(spill_env_t *env, firm_dbg_module_t *dbg) {
+ env->dbg = dbg;
+}
+)
+
+/* Creates a new spill environment. */
+spill_env_t *be_new_spill_env(be_irg_t *birg) {
+ 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 = birg->main_env->arch_env;
+ env->mem_phis = pset_new_ptr_default();
+ // TODO, ask backend about costs..., or even ask backend whether we should
+ // rematerialize...
+ env->spill_cost = 8;
+ env->reload_cost = 5;
obstack_init(&env->obst);
return env;
}
-void be_delete_spill_env(spill_env_t *senv) {
- del_set(senv->spill_ctxs);
- del_set(senv->spills);
- obstack_free(&senv->obst, NULL);
- free(senv);
+/* Deletes a spill environment. */
+void be_delete_spill_env(spill_env_t *env) {
+ del_set(env->spills);
+ del_pset(env->mem_phis);
+ obstack_free(&env->obst, NULL);
+ free(env);
}
-static spill_ctx_t *be_get_spill_ctx(set *sc, ir_node *to_spill, ir_node *ctx_irn) {
- spill_ctx_t templ;
+/*
+ * ____ _ ____ _ _
+ * | _ \| | __ _ ___ ___ | _ \ ___| | ___ __ _ __| |___
+ * | |_) | |/ _` |/ __/ _ \ | |_) / _ \ |/ _ \ / _` |/ _` / __|
+ * | __/| | (_| | (_| __/ | _ < __/ | (_) | (_| | (_| \__ \
+ * |_| |_|\__,_|\___\___| |_| \_\___|_|\___/ \__,_|\__,_|___/
+ *
+ */
+
+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);
- templ.spilled = to_spill;
- templ.user = ctx_irn;
- templ.spill = NULL;
+ /* 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->allow_remat = 1;
- return set_insert(sc, &templ, sizeof(templ), HASH_COMBINE(HASH_PTR(to_spill), HASH_PTR(ctx_irn)));
+ spill_info->reloaders = reloader;
}
-static ir_node *be_spill_irn(spill_env_t *senv, ir_node *irn, ir_node *ctx_irn) {
- spill_ctx_t *ctx;
- DBG((senv->dbg, LEVEL_1, "%+F in ctx %+F\n", irn, ctx_irn));
+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);
- ctx = be_get_spill_ctx(senv->spill_ctxs, irn, ctx_irn);
- if(!ctx->spill) {
- const be_main_env_t *env = senv->chordal_env->main_env;
- ctx->spill = be_spill(env->node_factory, env->arch_env, irn);
+ if (is_Phi(to_spill)) {
+ int i, arity;
+
+ /* 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);
+ }
+
+#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);
+ }
+#endif
}
- return ctx->spill;
+ /* put reload into list */
+ rel = obstack_alloc(&env->obst, sizeof(rel[0]));
+ rel->next = info->reloaders;
+ rel->reloader = before;
+ rel->rematted_node = NULL;
+ rel->allow_remat = allow_remat;
+
+ info->reloaders = rel;
+ assert(info->reload_cls == NULL || info->reload_cls == reload_cls);
+ info->reload_cls = reload_cls;
}
+static ir_node *get_reload_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)) {
+ ir_graph *irg = get_irn_irg(block);
+ ir_node *startblock = get_irg_start_block(irg);
+
+ last = sched_next(last);
+ // last node must be a cfop, only exception is the start block
+ assert(last == startblock);
+ }
+
+ // 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_reload_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));
+
+ pset_insert_ptr(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;
+ }
+}
+
+/*
+ * ____ _ ____ _ _ _
+ * / ___|_ __ ___ __ _| |_ ___ / ___| _ __ (_) | |___
+ * | | | '__/ _ \/ _` | __/ _ \ \___ \| '_ \| | | / __|
+ * | |___| | | __/ (_| | || __/ ___) | |_) | | | \__ \
+ * \____|_| \___|\__,_|\__\___| |____/| .__/|_|_|_|___/
+ * |_|
+ */
+
/**
- * If the first usage of a phi result would be out of memory
+ * 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)) {
+ 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) {
+ ir_node *to_spill = spillinfo->spilled_node;
+
+ DBG((env->dbg, LEVEL_1, "%+F\n", 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
+ *
+ * (although rematerialization code should handle most of these cases
+ * this can still happen when spilling Phis)
+ */
+ if(be_is_Reload(to_spill)) {
+ spillinfo->spill = get_irn_n(to_spill, be_pos_Reload_mem);
+ return;
+ }
+
+ if (arch_irn_is(env->arch_env, to_spill, dont_spill)) {
+ assert(0 && "Attempt to spill a node marked 'dont_spill'");
+ }
+
+ spillinfo->spill = be_spill(env->arch_env, to_spill);
+ sched_add_after_insn(to_spill, spillinfo->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 ir_node *be_spill_phi(spill_env_t *senv, ir_node *phi, ir_node *ctx_irn) {
- int i, n = get_irn_arity(phi);
- ir_node **ins, *bl = get_nodes_block(phi);
- ir_graph *irg = senv->chordal_env->irg;
- spill_ctx_t *ctx;
+static void spill_phi(spill_env_t *env, spill_info_t *spillinfo) {
+ ir_node *phi = spillinfo->spilled_node;
+ int i;
+ int arity = get_irn_arity(phi);
+ ir_node *block = get_nodes_block(phi);
+ ir_node **ins;
assert(is_Phi(phi));
- DBG((senv->dbg, LEVEL_1, "%+F in ctx %+F\n", phi, ctx_irn));
-
- /* search an existing spill for this context */
- ctx = be_get_spill_ctx(senv->spill_ctxs, phi, ctx_irn);
-
- /* if not found spill the phi */
- if(!ctx->spill) {
- /* build a new PhiM with dummy in-array */
- ins = malloc(n * sizeof(ins[0]));
- for(i=0; i<n; ++i)
- ins[i] = new_r_Unknown(irg, mode_M);
- ctx->spill = new_r_Phi(senv->chordal_env->irg, bl, n, ins, mode_M);
- free(ins);
-
- /* re-wire the phiM */
- for(i=0; i<n; ++i) {
- ir_node *arg = get_irn_n(phi, i);
- ir_node *sub_res;
-
- if(is_Phi(arg) && pset_find_ptr(senv->mem_phis, arg))
- sub_res = be_spill_phi(senv, arg, ctx_irn);
- else
- sub_res = be_spill_irn(senv, arg, ctx_irn);
-
- set_irn_n(ctx->spill, i, sub_res);
+
+ /* 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);
+
+ 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);
+ }
+
+ // 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;
+
+ foreach_out_edge_safe(old_spill, edge, next) {
+ ir_node* reload = get_edge_src_irn(edge);
+ assert(be_is_Reload(reload) || is_Phi(reload));
+ set_irn_n(reload, get_edge_src_pos(edge), spillinfo->spill);
}
+ set_irn_n(old_spill, be_pos_Spill_val, new_Bad());
+ //sched_remove(old_spill);
+ spillinfo->old_spill = NULL;
}
- return ctx->spill;
}
-static ir_node *be_spill_node(spill_env_t *senv, ir_node *to_spill) {
- ir_node *res;
- if (pset_find_ptr(senv->mem_phis, to_spill))
- res = be_spill_phi(senv, to_spill, to_spill);
- else
- res = be_spill_irn(senv, to_spill, to_spill);
+/**
+ * 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) {
+ ir_node *to_spill;
+
+ // the node should be tagged for spilling already...
+ if(spillinfo->spill != NULL)
+ return;
+
+ to_spill = spillinfo->spilled_node;
+ if (is_Phi(to_spill) && pset_find_ptr(env->mem_phis, spillinfo->spilled_node)) {
+ spill_phi(env, spillinfo);
+ } else {
+ spill_irn(env, spillinfo);
+ }
+}
- return res;
+/*
+ *
+ * ____ _ _ _ _
+ * | _ \ ___ _ __ ___ __ _| |_ ___ _ __(_) __ _| (_)_______
+ * | |_) / _ \ '_ ` _ \ / _` | __/ _ \ '__| |/ _` | | |_ / _ \
+ * | _ < __/ | | | | | (_| | || __/ | | | (_| | | |/ / __/
+ * |_| \_\___|_| |_| |_|\__,_|\__\___|_| |_|\__,_|_|_/___\___|
+ *
+ */
+
+/**
+ * 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) {
+ if(is_Unknown(arg) || arg == new_NoMem())
+ return 1;
+
+ if(be_is_Spill(arg))
+ return 1;
+
+ 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;
+ }
+
+#if 0
+ /* the following test does not work while spilling,
+ * because the liveness info is not adapted yet to the effects of the
+ * additional spills/reloads.
+ */
+
+ /* 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;
}
-static void phi_walker(ir_node *irn, void *env) {
- spill_env_t *senv = env;
- const arch_env_t *arch = senv->chordal_env->main_env->arch_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 (is_Phi(irn) && arch_irn_has_reg_class(arch, irn, 0, senv->cls)
- && senv->is_mem_phi(irn, senv->data)) {
- DBG((senv->dbg, LEVEL_1, " %+F\n", irn));
- pset_insert_ptr(senv->mem_phis, irn);
+ if(arch_irn_is(arch_env, node, rematerializable)) {
+ return 1;
}
+
+ if(be_is_StackParam(node))
+ return 1;
+
+ return 0;
}
-void be_insert_spills_reloads(spill_env_t *senv, pset *reload_set) {
- ir_graph *irg = senv->chordal_env->irg;
- ir_node *irn;
- spill_info_t *si;
- struct obstack ob;
-
- obstack_init(&ob);
-
- /* get all special spilled phis */
- DBG((senv->dbg, LEVEL_1, "Mem-phis:\n"));
- senv->mem_phis = pset_new_ptr_default();
- irg_walk_graph(senv->chordal_env->irg, phi_walker, NULL, senv);
-
- /* Add reloads for mem_phis */
- /* BETTER: These reloads (1) should only be inserted, if they are really needed */
- DBG((senv->dbg, LEVEL_1, "Reloads for mem-phis:\n"));
- for(irn = pset_first(senv->mem_phis); irn; irn = pset_next(senv->mem_phis)) {
- const ir_edge_t *e;
- DBG((senv->dbg, LEVEL_1, " Mem-phi %+F\n", irn));
- foreach_out_edge(irn, e) {
- ir_node *user = e->src;
- if (is_Phi(user) && !pset_find_ptr(senv->mem_phis, user)) {
- ir_node *use_bl = get_nodes_block(user);
- DBG((senv->dbg, LEVEL_1, " non-mem-phi user %+F\n", user));
- be_add_reload_on_edge(senv, irn, use_bl, e->pos); /* (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_LIMIT 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_LIMIT;
+
+ if(be_is_Reload(spilled)) {
+ costs += 2;
+ } else {
+ costs += arch_get_op_estimated_cost(env->arch_env, spilled);
+ }
+ if(parentcosts + costs >= REMAT_COST_LIMIT) {
+ return REMAT_COST_LIMIT;
}
- /* process each spilled node */
- DBG((senv->dbg, LEVEL_1, "Insert spills and reloads:\n"));
- for(si = set_first(senv->spills); si; si = set_next(senv->spills)) {
- reloader_t *rld;
- ir_node **reloads;
- int n_reloads = 0;
- ir_mode *mode = get_irn_mode(si->spilled_node);
+ argremats = 0;
+ for(i = 0, arity = get_irn_arity(spilled); i < arity; ++i) {
+ ir_node *arg = get_irn_n(spilled, i);
- /* go through all reloads for this spill */
- for(rld = si->reloaders; rld; rld = rld->next) {
- /* the spill for this reloader */
- ir_node *spill = be_spill_node(senv, si->spilled_node);
-
- /* the reload */
- ir_node *bl = is_Block(rld->reloader) ? rld->reloader : get_nodes_block(rld->reloader);
- ir_node *reload = new_Reload(senv->chordal_env->main_env->node_factory,
- senv->cls, irg, bl, mode, spill);
-
- DBG((senv->dbg, LEVEL_1, " %+F of %+F before %+F\n", reload, si->spilled_node, rld->reloader));
- if(reload_set)
- pset_insert_ptr(reload_set, reload);
-
- /* remember the reaload */
- obstack_ptr_grow(&ob, reload);
- sched_add_before(rld->reloader, reload);
- n_reloads++;
+ 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_LIMIT;
}
+ argremats++;
- assert(n_reloads > 0);
- reloads = obstack_finish(&ob);
- be_introduce_copies_ignore(senv->chordal_env->dom_front, si->spilled_node,
- n_reloads, reloads, senv->mem_phis);
- obstack_free(&ob, reloads);
+ costs += check_remat_conditions_costs(env, arg, reloader, parentcosts + costs);
+ if(parentcosts + costs >= REMAT_COST_LIMIT)
+ return REMAT_COST_LIMIT;
}
- obstack_free(&ob, NULL);
+ return costs;
+}
+
+static int check_remat_conditions(spill_env_t *env, ir_node *spilled, ir_node *reloader) {
+ int costs = check_remat_conditions_costs(env, spilled, reloader, 0);
- for(irn = pset_first(senv->mem_phis); irn; irn = pset_next(senv->mem_phis)) {
- int i, n;
- for(i = 0, n = get_irn_arity(irn); i < n; ++i)
- set_irn_n(irn, i, new_r_Bad(senv->chordal_env->irg));
- sched_remove(irn);
+ return costs < REMAT_COST_LIMIT;
+}
+
+/**
+ * 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);
+ }
}
- del_pset(senv->mem_phis);
+ /* 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);
+ sched_reset(res);
+
+ DBG((env->dbg, LEVEL_1, "Insert remat %+F of %+F before reloader %+F\n", res, spilled, reloader));
+
+ /* insert in schedule */
+ sched_add_before(reloader, res);
+
+ return res;
}
-void be_add_reload(spill_env_t *senv, ir_node *to_spill, ir_node *before) {
- spill_info_t templ, *res;
- reloader_t *rel;
+int be_get_reload_costs(spill_env_t *env, ir_node *to_spill, ir_node *before) {
+ spill_info_t *spill_info;
-// assert(get_irn_opcode(to_spill) != iro_Unknown);
+ if(be_do_remats) {
+ // is the node rematerializable?
+ int costs = check_remat_conditions_costs(env, to_spill, before, 0);
+ if(costs < REMAT_COST_LIMIT)
+ return costs;
+ }
+
+ // do we already have a spill?
+ spill_info = find_spillinfo(env, to_spill);
+ if(spill_info != NULL && spill_info->spill != NULL)
+ return env->reload_cost;
- templ.spilled_node = to_spill;
- templ.reloaders = NULL;
- res = set_insert(senv->spills, &templ, sizeof(templ), HASH_PTR(to_spill));
+ return env->spill_cost + env->reload_cost;
+}
- rel = obstack_alloc(&senv->obst, sizeof(rel[0]));
- rel->reloader = before;
- rel->next = res->reloaders;
- res->reloaders = rel;
+int be_get_reload_costs_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block, int pos) {
+ ir_node *before = get_reload_insertion_point(block, pos);
+ return be_get_reload_costs(env, to_spill, before);
}
-void be_add_reload_on_edge(spill_env_t *senv, ir_node *to_spill, ir_node *bl, int pos) {
- ir_node *insert_bl = get_irn_arity(bl) == 1 ? sched_first(bl) : get_Block_cfgpred_block(bl, pos);
- be_add_reload(senv, to_spill, insert_bl);
+/*
+ * ___ _ ____ _ _
+ * |_ _|_ __ ___ ___ _ __| |_ | _ \ ___| | ___ __ _ __| |___
+ * | || '_ \/ __|/ _ \ '__| __| | |_) / _ \ |/ _ \ / _` |/ _` / __|
+ * | || | | \__ \ __/ | | |_ | _ < __/ | (_) | (_| | (_| \__ \
+ * |___|_| |_|___/\___|_| \__| |_| \_\___|_|\___/ \__,_|\__,_|___/
+ *
+ */
+
+void be_insert_spills_reloads(spill_env_t *env) {
+ const arch_env_t *arch_env = env->arch_env;
+ int remats = 0;
+ int reloads = 0;
+ int spills = 0;
+ spill_info_t *si;
+
+ /* process each spilled node */
+ for (si = set_first(env->spills); si; si = set_next(env->spills)) {
+ reloader_t *rld;
+ ir_mode *mode = get_irn_mode(si->spilled_node);
+ pset *values = pset_new_ptr(16);
+
+ /* go through all reloads for this spill */
+ for (rld = si->reloaders; rld; rld = rld->next) {
+ ir_node *new_val;
+
+ if (rld->rematted_node != NULL) {
+ new_val = rld->rematted_node;
+ remats++;
+ sched_add_before(rld->reloader, new_val);
+ }
+ else if (be_do_remats && rld->allow_remat && check_remat_conditions(env, si->spilled_node, rld->reloader)) {
+ new_val = do_remat(env, si->spilled_node, rld->reloader);
+ remats++;
+ }
+ else {
+ /* make sure we have a spill */
+ if (si->spill == NULL) {
+ spill_node(env, si);
+ spills++;
+ }
+
+ /* create a reload */
+ new_val = be_reload(arch_env, si->reload_cls, rld->reloader, mode, si->spill);
+ reloads++;
+ }
+
+ DBG((env->dbg, LEVEL_1, " %+F of %+F before %+F\n", new_val, si->spilled_node, rld->reloader));
+ pset_insert_ptr(values, new_val);
+ }
+
+ if (pset_count(values) > 0) {
+ /* introduce copies, rewire the uses */
+ pset_insert_ptr(values, si->spilled_node);
+ be_ssa_constr_set_ignore(env->birg->dom_front, env->birg->lv, values, env->mem_phis);
+ }
+
+ del_pset(values);
+
+ si->reloaders = NULL;
+ }
+
+#ifdef FIRM_STATISTICS
+ if (be_stat_ev_is_active()) {
+ be_stat_ev("spill_spills", spills);
+ be_stat_ev("spill_reloads", reloads);
+ be_stat_ev("spill_remats", remats);
+ }
+#endif /* FIRM_STATISTICS */
+
+ be_remove_dead_nodes_from_schedule(env->irg);
+ //be_liveness_recompute(env->birg->lv);
+ be_invalidate_liveness(env->birg);
}