#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 "benode_t.h"
#include "bechordal_t.h"
#include "bejavacoal.h"
+#include "benodesets.h"
// only rematerialise when costs are less than REMAT_COST_LIMIT
// TODO determine a good value here...
-#define REMAT_COST_LIMIT 80
+#define REMAT_COST_LIMIT 10
typedef struct _reloader_t reloader_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;
+ /** 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;
} spill_info_t;
struct _spill_env_t {
const arch_env_t *arch_env;
const be_chordal_env_t *chordal_env;
struct obstack obst;
- set *spills; /**< all spill_info_t's, which must be placed */
- pset *mem_phis; /**< set of all special spilled phis. allocated and freed separately */
+ 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 */
DEBUG_ONLY(firm_dbg_module_t *dbg;)
};
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 = HASH_PTR(value);
+ 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;
res = set_insert(env->spills, &info, sizeof(info), hash);
}
env->chordal_env = chordal_env;
env->arch_env = env->chordal_env->birg->main_env->arch_env;
env->mem_phis = pset_new_ptr_default();
+ // TODO, ask backend about costs...
+ env->spill_cost = 8;
+ env->reload_cost = 5;
obstack_init(&env->obst);
return env;
}
rel->reloader = before;
rel->next = info->reloaders;
info->reloaders = rel;
- be_liveness_add_missing(env->chordal_env->lv);
}
-void be_add_reload_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block, int pos) {
+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
*/
if(get_Block_n_cfgpreds(block) == 1) {
assert(!is_Phi(sched_first(block)));
- be_add_reload(env, to_spill, sched_first(block));
- return;
+ return sched_first(block);
}
/* We have to reload the value in pred-block */
assert(is_cfop(last));
// add the reload before the (cond-)jump
- be_add_reload(env, to_spill, last);
+ return last;
+}
+
+void be_add_reload_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block, int pos) {
+ ir_node *before = get_reload_insertion_point(block, pos);
+ be_add_reload(env, to_spill, before);
}
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
- get_spillinfo(env, node);
+ 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)) {
+ spill->old_spill = spill->spill;
+ spill->spill = NULL;
+ }
}
/*
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;
+ foreach_out_edge_safe(spillinfo->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);
+ }
+ spillinfo->old_spill = NULL;
+ }
}
/**
assert(!be_is_Spill(node));
- if(be_is_Reload(node))
- return 1;
-
- // TODO why does arch_irn_is say rematerializable anyway?
- if(be_is_Barrier(node))
- return 0;
-
- if(arch_irn_is(arch_env, node, rematerializable))
+ if(arch_irn_is(arch_env, node, rematerializable)) {
return 1;
+ }
if(be_is_StackParam(node))
return 1;
} else {
costs += arch_get_op_estimated_cost(env->arch_env, spilled);
}
- if(parentcosts + costs >= REMAT_COST_LIMIT)
+ if(parentcosts + costs >= REMAT_COST_LIMIT) {
return REMAT_COST_LIMIT;
+ }
argremats = 0;
for(i = 0, arity = get_irn_arity(spilled); i < arity; ++i) {
}
argremats++;
- // TODO can we get more accurate costs than +1?
costs += check_remat_conditions_costs(env, arg, reloader, parentcosts + costs);
if(parentcosts + costs >= REMAT_COST_LIMIT)
return REMAT_COST_LIMIT;
}
static int check_remat_conditions(spill_env_t *env, ir_node *spilled, ir_node *reloader) {
- int costs = check_remat_conditions_costs(env, spilled, reloader, 1);
+ int costs = check_remat_conditions_costs(env, spilled, reloader, 0);
return costs < REMAT_COST_LIMIT;
}
get_irn_arity(spilled),
ins);
copy_node_attr(spilled, res);
+ new_backedge_info(res);
DBG((env->dbg, LEVEL_1, "Insert remat %+F before reloader %+F\n", res, reloader));
return res;
}
+int be_get_reload_costs(spill_env_t *env, ir_node *to_spill, ir_node *before) {
+ spill_info_t *spill_info;
+
+ // 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;
+
+ return env->spill_cost + env->reload_cost;
+}
+
+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);
+}
+
/*
* ___ _ ____ _ _
* |_ _|_ __ ___ ___ _ __| |_ | _ \ ___| | ___ __ _ __| |___
spill_info_t *si;
/* process each spilled node */
- DBG((env->dbg, LEVEL_1, "Insert spills and reloads:\n"));
for(si = set_first(env->spills); si; si = set_next(env->spills)) {
reloader_t *rld;
ir_mode *mode = get_irn_mode(si->spilled_node);
}
del_pset(values);
+
+ si->reloaders = NULL;
}
- // reloads are placed now, but we might reuse the spill environment for further spilling decisions
- del_set(env->spills);
- env->spills = new_set(cmp_spillinfo, 1024);
+ be_remove_dead_nodes_from_schedule(env->chordal_env->irg);
+ be_liveness_recompute(env->chordal_env->lv);
}