/*
- * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved.
+ * Copyright (C) 1995-2008 University of Karlsruhe. All right reserved.
*
* This file is part of libFirm.
*
DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;)
-typedef struct daemel_env_t daemel_env_t;
-struct daemel_env_t {
- spill_env_t *spill_env;
- int n_regs;
- const arch_env_t *arch_env;
- const arch_register_class_t *cls;
- const be_lv_t *lv;
- bitset_t *spilled_nodes;
-};
+static spill_env_t *spill_env;
+static int n_regs;
+static const arch_env_t *arch_env;
+static const arch_register_class_t *cls;
+static const be_lv_t *lv;
+static bitset_t *spilled_nodes;
typedef struct spill_candidate_t spill_candidate_t;
struct spill_candidate_t {
ir_node *node;
};
-static
-int compare_spill_candidates_desc(const void *d1, const void *d2)
+static int compare_spill_candidates_desc(const void *d1, const void *d2)
{
const spill_candidate_t *c1 = d1;
const spill_candidate_t *c2 = d2;
return (int) (c1->costs - c2->costs);
}
-static
-double get_spill_costs(daemel_env_t *env, ir_node *node)
+static double get_spill_costs(ir_node *node)
{
const ir_edge_t *edge;
- spill_env_t *spill_env = env->spill_env;
- double costs = be_get_spill_costs(spill_env, node, node);
+ ir_node *spill_place = skip_Proj(node);
+ double costs = be_get_spill_costs(spill_env, node,
+ spill_place);
foreach_out_edge(node, edge) {
ir_node *use = get_edge_src_irn(edge);
+ /* keeps should be directly below the node */
+ if(be_is_Keep(use)) {
+ continue;
+ }
+
if(is_Phi(use)) {
- int in = get_edge_src_pos(edge);
- ir_node *block = get_nodes_block(use);
+ int in = get_edge_src_pos(edge);
+ ir_node *block = get_nodes_block(use);
costs += be_get_reload_costs_on_edge(spill_env, node, block, in);
} else {
}
}
+ /* TODO cache costs? */
+
return costs;
}
/**
* spills a node by placing a reload before each usage
*/
-static
-void spill_node(daemel_env_t *env, ir_node *node, ir_nodeset_t *nodes)
+static void spill_node(ir_node *node)
{
const ir_edge_t *edge;
- spill_env_t *spill_env = env->spill_env;
- const arch_register_class_t *cls = env->cls;
DBG((dbg, LEVEL_3, "\tspilling %+F\n", node));
foreach_out_edge(node, edge) {
ir_node *use = get_edge_src_irn(edge);
+ if(is_Anchor(use))
+ continue;
+ if(be_is_Keep(use))
+ continue;
if(is_Phi(use)) {
int in = get_edge_src_pos(edge);
ir_node *block = get_nodes_block(use);
be_add_reload_on_edge(spill_env, node, block, in, cls, 1);
- } else if(!be_is_Keep(use)) {
+ } else {
be_add_reload(spill_env, node, use, cls, 1);
}
}
- bitset_set(env->spilled_nodes, get_irn_idx(node));
- ir_nodeset_remove(nodes, node);
+ bitset_set(spilled_nodes, get_irn_idx(node));
}
/**
* spill @p n nodes from a nodeset. Removes the nodes from the nodeset and
- * sets the spilled bits in env->spilled_nodes.
+ * sets the spilled bits in spilled_nodes.
*/
-static
-void do_spilling(daemel_env_t *env, ir_nodeset_t *nodes, ir_node *node)
+static void do_spilling(ir_nodeset_t *live_nodes, ir_node *node)
{
- size_t node_count = ir_nodeset_size(nodes);
- size_t additional_defines = 0;
- size_t reload_values = 0;
- int registers = env->n_regs;
- const arch_env_t *arch_env = env->arch_env;
- const arch_register_class_t *cls = env->cls;
- spill_candidate_t *candidates;
- ir_nodeset_iterator_t iter;
- size_t i, arity;
- int spills_needed;
- size_t cand_idx;
- ir_node *n;
- const bitset_t *spilled_nodes = env->spilled_nodes;
+ size_t n_live_nodes = ir_nodeset_size(live_nodes);
+ size_t values_defined = 0;
+ size_t free_regs_needed = 0;
+ spill_candidate_t *candidates;
+ ir_nodeset_iterator_t iter;
+ size_t i, arity;
+ int spills_needed;
+ size_t cand_idx;
+ ir_node *n;
/* mode_T nodes define several values at once. Count them */
if(get_irn_mode(node) == mode_T) {
- ir_node *proj = sched_next(node);
+ const ir_edge_t *edge;
+
+ foreach_out_edge(node, edge) {
+ const ir_node *proj = get_edge_src_irn(edge);
- while(is_Proj(proj)) {
- if(arch_irn_consider_in_reg_alloc(arch_env, cls, proj)) {
- ++additional_defines;
+ if (arch_irn_consider_in_reg_alloc(cls, proj)) {
+ ++values_defined;
}
- proj = sched_next(proj);
}
+ } else if (arch_irn_consider_in_reg_alloc(cls, node)) {
+ ++values_defined;
}
- /* we might temporarily need registers for reloaded values */
+ /* we need registers for the non-live argument values */
arity = get_irn_arity(node);
for(i = 0; i < arity; ++i) {
ir_node *pred = get_irn_n(node, i);
- if(bitset_is_set(spilled_nodes, get_irn_idx(pred)))
- ++reload_values;
+ if (arch_irn_consider_in_reg_alloc(cls, pred)
+ && !ir_nodeset_contains(live_nodes, pred)) {
+ ++free_regs_needed;
+ }
}
- if(reload_values > additional_defines)
- additional_defines = reload_values;
+ /* we can reuse all reloaded values for the defined values, but we might
+ need even more registers */
+ if(values_defined > free_regs_needed)
+ free_regs_needed = values_defined;
- spills_needed = (node_count + additional_defines) - registers;
+ spills_needed = (n_live_nodes + free_regs_needed) - n_regs;
if(spills_needed <= 0)
return;
DBG((dbg, LEVEL_2, "\tspills needed after %+F: %d\n", node, spills_needed));
- candidates = malloc(node_count * sizeof(candidates[0]));
+ candidates = alloca(n_live_nodes * sizeof(candidates[0]));
/* construct array with spill candidates and calculate their costs */
i = 0;
- foreach_ir_nodeset(nodes, n, iter) {
+ foreach_ir_nodeset(live_nodes, n, iter) {
spill_candidate_t *candidate = & candidates[i];
+ assert(!bitset_is_set(spilled_nodes, get_irn_idx(n)));
+
candidate->node = n;
- candidate->costs = get_spill_costs(env, n);
+ candidate->costs = get_spill_costs(n);
++i;
}
- assert(i == node_count);
+ assert(i == n_live_nodes);
/* sort spill candidates */
- qsort(candidates, node_count, sizeof(candidates[0]),
+ qsort(candidates, n_live_nodes, sizeof(candidates[0]),
compare_spill_candidates_desc);
/* spill cheapest ones */
cand_idx = 0;
while(spills_needed > 0) {
- if(cand_idx >= node_count) {
- panic("can't spill enough values for node %+F\n", node);
+ spill_candidate_t *candidate;
+ ir_node *cand_node;
+ int is_use;
+
+ if (cand_idx >= n_live_nodes) {
+ panic("can't spill enough values for node %+F", node);
}
- spill_candidate_t *candidate = &candidates[cand_idx];
- ir_node *cand_node = candidate->node;
- int is_use;
+
+ candidate = &candidates[cand_idx];
+ cand_node = candidate->node;
++cand_idx;
- /* make sure the node is not a use of the instruction */
+ if (arch_irn_is(cand_node, dont_spill))
+ continue;
+
+ /* make sure the node is not an argument of the instruction */
is_use = 0;
- for(i = 0; i < arity; ++i) {
+ for (i = 0; i < arity; ++i) {
ir_node *in = get_irn_n(node, i);
if(in == cand_node) {
is_use = 1;
continue;
}
- spill_node(env, cand_node, nodes);
+ spill_node(cand_node);
+ ir_nodeset_remove(live_nodes, cand_node);
--spills_needed;
}
-
- free(candidates);
}
/**
- * similar to be_liveness_transfer.
- * custom liveness transfer function, that doesn't place already spilled values
- * into the liveness set
+ * removes all values from the nodeset that are defined by node
*/
-static
-void liveness_transfer(daemel_env_t *env, ir_node *node, ir_nodeset_t *nodeset)
+static void remove_defs(ir_node *node, ir_nodeset_t *nodeset)
{
- int i, arity;
- const arch_register_class_t *cls = env->cls;
- const arch_env_t *arch_env = env->arch_env;
- const bitset_t *bitset = env->spilled_nodes;
-
/* You should better break out of your loop when hitting the first phi
* function. */
assert(!is_Phi(node) && "liveness_transfer produces invalid results for phi nodes");
- if(arch_irn_consider_in_reg_alloc(arch_env, cls, node)) {
- ir_nodeset_remove(nodeset, node);
- }
+ if (get_irn_mode(node) == mode_T) {
+ const ir_edge_t *edge;
- arity = get_irn_arity(node);
- for(i = 0; i < arity; ++i) {
- ir_node *op = get_irn_n(node, i);
+ foreach_out_edge(node, edge) {
+ const ir_node *proj = get_edge_src_irn(edge);
- if(arch_irn_consider_in_reg_alloc(arch_env, cls, op)
- && !bitset_is_set(bitset, get_irn_idx(op))) {
- ir_nodeset_insert(nodeset, op);
+ if (arch_irn_consider_in_reg_alloc(cls, proj)) {
+ ir_nodeset_remove(nodeset, proj);
+ }
}
- }
+ }
+
+ if (arch_irn_consider_in_reg_alloc(cls, node)) {
+ ir_nodeset_remove(nodeset, node);
+ }
+}
+
+static void add_uses(ir_node *node, ir_nodeset_t *nodeset)
+{
+ int i, arity;
+
+ arity = get_irn_arity(node);
+ for(i = 0; i < arity; ++i) {
+ ir_node *op = get_irn_n(node, i);
+
+ if (arch_irn_consider_in_reg_alloc(cls, op) &&
+ !bitset_is_set(spilled_nodes, get_irn_idx(op))) {
+ ir_nodeset_insert(nodeset, op);
+ }
+ }
+}
+
+static __attribute__((unused))
+void print_nodeset(ir_nodeset_t *nodeset)
+{
+ ir_nodeset_iterator_t iter;
+ ir_node *node;
+
+ foreach_ir_nodeset(nodeset, node, iter) {
+ ir_fprintf(stderr, "%+F ", node);
+ }
+ fprintf(stderr, "\n");
}
/**
* make sure register pressure in a block is always equal or below the number
* of available registers
*/
-static
-void spill_block(ir_node *block, void *data)
+static void spill_block(ir_node *block, void *data)
{
- daemel_env_t *env = data;
- const arch_env_t *arch_env = env->arch_env;
- const arch_register_class_t *cls = env->cls;
- const be_lv_t *lv = env->lv;
- ir_nodeset_t live_nodes;
- ir_nodeset_iterator_t iter;
- ir_node *node;
- bitset_t *spilled_nodes = env->spilled_nodes;
- int phi_count;
+ ir_nodeset_t live_nodes;
+ ir_nodeset_iterator_t iter;
+ ir_node *node;
+ int n_phi_values_spilled;
+ int regpressure;
+ int phi_spills_needed;
+ (void) data;
DBG((dbg, LEVEL_1, "spilling block %+F\n", block));
+ /* construct set of live nodes at end of block */
ir_nodeset_init(&live_nodes);
- be_liveness_end_of_block_ir_nodeset(lv, arch_env, cls, block, &live_nodes);
+ be_liveness_end_of_block(lv, arch_env, cls, block, &live_nodes);
+ /* remove already spilled nodes from liveset */
foreach_ir_nodeset(&live_nodes, node, iter) {
- DBG((dbg, LEVEL_2, "\t%+F is live-in... ", node));
+ DBG((dbg, LEVEL_2, "\t%+F is live-end... ", node));
if(bitset_is_set(spilled_nodes, get_irn_idx(node))) {
DBG((dbg, LEVEL_2, "but spilled; removing.\n"));
+ ir_nodeset_remove_iterator(&live_nodes, &iter);
} else {
DBG((dbg, LEVEL_2, "keeping.\n"));
}
}
+ /* walk schedule backwards and spill until register pressure is fine at
+ * each node */
sched_foreach_reverse(block, node) {
if(is_Phi(node))
break;
- if(is_Proj(node) || be_is_Keep(node)) {
- liveness_transfer(env, node, &live_nodes);
- continue;
- }
-
- do_spilling(env, &live_nodes, node);
- liveness_transfer(env, node, &live_nodes);
+ remove_defs(node, &live_nodes);
+ do_spilling(&live_nodes, node);
+ add_uses(node, &live_nodes);
}
- do_spilling(env, &live_nodes, node);
- phi_count = 0;
- int spilled_phis = 0;
+ /* until now only the values of some phis have been spilled the phis itself
+ * are still there and occupy registers, so we need to count them and might
+ * have to spill some of them.
+ */
+ n_phi_values_spilled = 0;
sched_foreach(block, node) {
if(!is_Phi(node))
break;
- ++phi_count;
if(bitset_is_set(spilled_nodes, get_irn_idx(node))) {
- ++spilled_phis;
+ ++n_phi_values_spilled;
}
}
- int regpressure = ir_nodeset_size(&live_nodes) - spilled_phis;
- int phi_spills_needed = regpressure - env->n_regs;
+
+ /* calculate how many of the phis need to be spilled */
+ regpressure = ir_nodeset_size(&live_nodes) + n_phi_values_spilled;
+ phi_spills_needed = regpressure - n_regs;
+ DBG((dbg, LEVEL_3, "Regpressure before phis: %d phispills: %d\n",
+ regpressure, phi_spills_needed));
+
+ /* spill as many phis as needed */
+ /* TODO: we should really estimate costs of the phi spill as well...
+ * and preferably spill phis with lower costs... */
sched_foreach(block, node) {
if(!is_Phi(node))
break;
break;
if(bitset_is_set(spilled_nodes, get_irn_idx(node))) {
- be_spill_phi(env->spill_env, node);
+ be_spill_phi(spill_env, node);
--phi_spills_needed;
}
}
ir_nodeset_destroy(&live_nodes);
}
-void be_spill_daemel(be_irg_t *birg, const arch_register_class_t *cls)
+void be_spill_daemel(be_irg_t *birg, const arch_register_class_t *new_cls)
{
- daemel_env_t env;
ir_graph *irg = be_get_birg_irg(birg);
- int n_regs = cls->n_regs - be_put_ignore_regs(birg, cls, NULL);
+ n_regs = new_cls->n_regs - be_put_ignore_regs(birg, new_cls, NULL);
if(n_regs == 0)
return;
- be_invalidate_liveness(birg);
- be_assure_liveness(birg);
+ be_liveness_assure_sets(be_assure_liveness(birg));
+
+ spill_env = be_new_spill_env(birg);
+ arch_env = be_get_birg_arch_env(birg);
+ cls = new_cls;
+ lv = be_get_birg_liveness(birg);
+ spilled_nodes = bitset_malloc(get_irg_last_idx(irg));
- env.spill_env = be_new_spill_env(birg);
- env.n_regs = n_regs;
- env.arch_env = be_get_birg_arch_env(birg);
- env.cls = cls;
- env.lv = be_get_birg_liveness(birg);
- env.spilled_nodes = bitset_malloc(get_irg_last_idx(irg));
+ DBG((dbg, LEVEL_1, "*** RegClass %s\n", cls->name));
- irg_block_walk_graph(irg, spill_block, NULL, &env);
+ irg_block_walk_graph(irg, spill_block, NULL, NULL);
- bitset_free(env.spilled_nodes);
+ bitset_free(spilled_nodes);
+ spilled_nodes = NULL;
- be_insert_spills_reloads(env.spill_env);
+ be_insert_spills_reloads(spill_env);
- be_delete_spill_env(env.spill_env);
+ be_delete_spill_env(spill_env);
+ spill_env = NULL;
}
void be_init_daemelspill(void)
};
be_register_spiller("daemel", &daemel_spiller);
- FIRM_DBG_REGISTER(dbg, "ir.be.spilldaemel");
+ FIRM_DBG_REGISTER(dbg, "firm.be.spilldaemel");
}
-BE_REGISTER_MODULE_CONSTRUCTOR(be_init_doedelspill);
+BE_REGISTER_MODULE_CONSTRUCTOR(be_init_daemelspill);
projects / libfirm / blobdiff