#define DBG_LOOPANA 2
#define DBG_PRESSURE 4
#define DBG_SPILLS 8
+#define DBG_CHOOSE 16
DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
typedef struct morgan_env {
res = set_find(env->block_attr_set, &b_attr, sizeof(b_attr), hash);
if(res == NULL) {
- b_attr.livethrough_unused = bitset_obstack_alloc(&env->obst, get_irg_last_idx(env->irg));
+ b_attr.livethrough_unused = NULL;
res = set_insert(env->block_attr_set, &b_attr, sizeof(b_attr), hash);
}
}
#endif
-/**
- * Construct the livethrough unused set for a block
- */
-static bitset_t *construct_block_livethrough_unused(morgan_env_t* env, const ir_node* block) {
- block_attr_t *block_attr = get_block_attr(env, block);
- ir_node *node;
+static INLINE void init_livethrough_unuseds(block_attr_t *attr, morgan_env_t *env) {
+ const ir_node *block;
int i;
- DBG((dbg, DBG_LIVE, "Processing block %d\n", get_irn_node_nr(block)));
+ if(attr->livethrough_unused != NULL)
+ return;
+
+ block = attr->block;
+
+ attr->livethrough_unused = bitset_obstack_alloc(&env->obst, get_irg_last_idx(env->irg));
+
// copy all live-outs into the livethrough_unused set
be_lv_foreach(env->cenv->lv, block, be_lv_state_in | be_lv_state_out, i) {
ir_node *irn = be_lv_get_irn(env->cenv->lv, block, i);
continue;
node_idx = get_irn_idx(irn);
- bitset_set(block_attr->livethrough_unused, node_idx);
+ bitset_set(attr->livethrough_unused, node_idx);
+ }
+}
+
+/**
+ * Construct the livethrough unused set for a block
+ */
+static void construct_block_livethrough_unused(ir_node *block, void *data) {
+ morgan_env_t* env = data;
+ block_attr_t *block_attr = get_block_attr(env, block);
+ ir_node *node;
+ int n_cfgpreds;
+ block_attr_t **pred_attrs = NULL;
+ int i;
+
+ init_livethrough_unuseds(block_attr, env);
+
+ DBG((dbg, DBG_LIVE, "Processing block %d\n", get_irn_node_nr(block)));
+
+ n_cfgpreds = get_Block_n_cfgpreds(block);
+ if(n_cfgpreds > 1) {
+ pred_attrs = alloca(sizeof(pred_attrs[0]) * n_cfgpreds);
+ for(i = 0; i < n_cfgpreds; ++i) {
+ ir_node *pred_block = get_Block_cfgpred_block(block, i);
+ pred_attrs[i] = get_block_attr(env, pred_block);
+ init_livethrough_unuseds(pred_attrs[i], env);
+ }
}
/*
sched_foreach(block, node) {
int i, arity;
- for(i = 0, arity = get_irn_arity(node); i < arity; ++i) {
- int idx = get_irn_idx(get_irn_n(node, i));
- bitset_clear(block_attr->livethrough_unused, idx);
+ // phis are really uses in the pred block
+ if(is_Phi(node)) {
+ int j;
+ for(j = 0; j < n_cfgpreds; ++j) {
+ ir_node *used_value = get_Phi_pred(node, j);
+ int idx = get_irn_idx(used_value);
+ block_attr_t *pred_attr = pred_attrs[j];
+
+ bitset_clear(pred_attr->livethrough_unused, idx);
+ }
+ } else {
+ // mark all used values as used
+ for(i = 0, arity = get_irn_arity(node); i < arity; ++i) {
+ int idx = get_irn_idx(get_irn_n(node, i));
+ bitset_clear(block_attr->livethrough_unused, idx);
+ }
}
}
-
- return block_attr->livethrough_unused;
}
/**
loop_element elem = get_loop_element(loop, i);
switch (*elem.kind) {
case k_ir_node: {
- bitset_t *livethrough_block_unused;
+ ir_node *block = elem.node;
+ block_attr_t *block_attr = get_block_attr(env, block);
+ bitset_t *livethrough_block_unused = block_attr->livethrough_unused;
+
assert(is_Block(elem.node));
- livethrough_block_unused = construct_block_livethrough_unused(env, elem.node);
+ assert(livethrough_block_unused != NULL);
+
if(i == 0) {
bitset_copy(loop_attr->livethrough_unused, livethrough_block_unused);
} else {
/*---------------------------------------------------------------------------*/
+typedef struct _spillcandidate_t {
+ ir_node *node;
+ int cost;
+} spillcandidate_t;
+
+static int compare_spillcandidates(const void *d1, const void *d2) {
+ const spillcandidate_t *cand1 = d1;
+ const spillcandidate_t *cand2 = d2;
+
+ return cand1->cost - cand2->cost;
+}
+
+static void spill_values(morgan_env_t *env, const loop_attr_t *loop_attr, int spills) {
+ const bitset_t *cand_bitset = loop_attr->livethrough_unused;
+ int candidatecount = bitset_popcnt(cand_bitset);
+ spillcandidate_t *candidates;
+ int i, c;
+ loop_edge_t *edge;
+
+ assert(spills <= candidatecount);
+
+ candidates = alloca(sizeof(candidates[0]) * candidatecount);
+
+ DBG((dbg, DBG_CHOOSE, "Candidates for loop %d\n", get_loop_loop_nr(loop_attr->loop)));
+ // build candidiatelist
+ c = 0;
+ bitset_foreach(cand_bitset, i) {
+ ir_node *node = get_idx_irn(env->irg, i);
+ candidates[c].node = node;
+ candidates[c].cost = 0;
+
+ for(edge = set_first(loop_attr->out_edges); edge != NULL; edge = set_next(loop_attr->out_edges)) {
+ candidates[c].cost += be_get_reload_costs_on_edge(env->senv, node, edge->block, edge->pos);
+ }
+ DBG((dbg, DBG_CHOOSE, "%+F has costs %d\n", node, candidates[c].cost));
+
+ c++;
+ }
+ assert(c == candidatecount);
+
+ // sort list
+ qsort(candidates, candidatecount, sizeof(candidates[0]), compare_spillcandidates);
+
+ // spill values
+ for(i = 0; i < spills; ++i) {
+ ir_node *to_spill = candidates[i].node;
+ DBG((dbg, DBG_CHOOSE, "Spilling %+F ", to_spill));
+
+ for(edge = set_first(loop_attr->out_edges); edge != NULL; edge = set_next(loop_attr->out_edges)) {
+ be_add_reload_on_edge(env->senv, to_spill, edge->block, edge->pos);
+ }
+ }
+}
+
static int reduce_register_pressure_in_block(morgan_env_t *env, const ir_node* block, int loop_unused_spills_possible) {
ir_node *node;
int max_pressure;
DBG((dbg, DBG_SPILLS, "%d values unused in loop %d, spilling %d\n",
spills_possible - outer_spills_possible, loop->loop_nr, spills_to_place));
- bitset_foreach(loop_attr->livethrough_unused, i) {
- loop_edge_t *edge;
- ir_node *to_spill = get_idx_irn(env->irg, i);
-
- DBG((dbg, DBG_SPILLS, "Spilling node %+F around loop %d\n", to_spill, loop->loop_nr));
-
- for(edge = set_first(loop_attr->out_edges); edge != NULL; edge = set_next(loop_attr->out_edges)) {
- be_add_reload_on_edge(env->senv, to_spill, edge->block, edge->pos);
- }
-
- spills_to_place--;
- if(spills_to_place <= 0) {
- break;
- }
- }
+ spill_values(env, loop_attr, spills_to_place);
} else {
outer_spills_needed = spills_needed;
}
construct_cf_backedges(chordal_env->irg);
/* construct loop out edges and livethrough_unused sets for loops and blocks */
- irg_block_walk_graph(chordal_env->irg, NULL, construct_loop_edges, &env);
+ irg_block_walk_graph(chordal_env->irg, construct_block_livethrough_unused, construct_loop_edges, &env);
construct_loop_livethrough_unused(&env, get_irg_loop(env.irg));
/*-- Part2: Transformation --*/
projects / libfirm / blobdiff