X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbespilldaemel.c;h=ef36c8f298b5eff9acd85f372fe7e433c6da054f;hb=6f068af98daa4725d60e5d23a8f98ec2841cfa44;hp=09dbee2c575a4751f3c9f55e492d9a1012dd70a5;hpb=8c0c0da8b9491b45b1cb20501faa42c1afb82889;p=libfirm diff --git a/ir/be/bespilldaemel.c b/ir/be/bespilldaemel.c index 09dbee2c5..ef36c8f29 100644 --- a/ir/be/bespilldaemel.c +++ b/ir/be/bespilldaemel.c @@ -1,5 +1,5 @@ /* - * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved. + * Copyright (C) 1995-2011 University of Karlsruhe. All right reserved. * * This file is part of libFirm. * @@ -19,23 +19,21 @@ /** * @file - * @brief Naiv spilling algorithm + * @brief Naive spilling algorithm * @author Matthias Braun * @date 20.09.2005 * @version $Id: bespillbelady.c 13913 2007-05-18 12:48:56Z matze $ - * @summary - * This implements a naiv spilling algorithm. It is design to produce similar - * effects to the spill decisions produced by traditional graph coloring - * register allocators that spill while they are coloring the graph. + * @brief + * This implements a naive spilling algorithm. It is designed to produce + * similar effects to the spill decisions produced by traditional graph + * coloring register allocators that spill while they are coloring the graph. * * This spiller walks over all blocks and looks for places with too high * register pressure where it spills the values that are cheapest to spill. * Spilling in this context means placing a spill instruction behind the * definition of the value and a reload before each usage. */ -#ifdef HAVE_CONFIG_H #include "config.h" -#endif #include "debug.h" @@ -46,26 +44,23 @@ #include "error.h" #include "beirg.h" -#include "bespilloptions.h" #include "bespill.h" +#include "bespillutil.h" #include "bemodule.h" #include "besched.h" -#include "bearch_t.h" +#include "bearch.h" #include "be_t.h" -#include "benode_t.h" +#include "benode.h" #include "beirg.h" +#include "belive.h" 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 unsigned n_regs; +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 { @@ -73,28 +68,32 @@ 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; + const spill_candidate_t *c1 = (const spill_candidate_t*)d1; + const spill_candidate_t *c2 = (const spill_candidate_t*)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); - if(is_Phi(use)) { - int in = get_edge_src_pos(edge); - ir_node *block = get_nodes_block(use); + /* 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); costs += be_get_reload_costs_on_edge(spill_env, node, block, in); } else { @@ -108,173 +107,162 @@ double get_spill_costs(daemel_env_t *env, ir_node *node) /** * spills a node by placing a reload before each usage */ -static -void spill_node(daemel_env_t *env, ir_node *node) +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)) { + 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)); + bitset_set(spilled_nodes, get_irn_idx(node)); +} + +static unsigned get_value_width(const ir_node *node) +{ + const arch_register_req_t *req = arch_get_register_req_out(node); + return req->width; } /** * 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 *live_nodes, ir_node *node) +static void do_spilling(ir_nodeset_t *live_nodes, ir_node *node) { - size_t node_count = ir_nodeset_size(live_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; - - /* mode_T nodes define several values at once. Count them */ - if(get_irn_mode(node) == mode_T) { - ir_node *proj = sched_next(node); - - while(is_Proj(proj)) { - if(arch_irn_consider_in_reg_alloc(arch_env, cls, proj)) { - ++additional_defines; - } - proj = sched_next(proj); - } - } - if(bitset_is_set(spilled_nodes, get_irn_idx(node))) - ++additional_defines; + 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; + int i, arity; + size_t c; + int spills_needed; + size_t cand_idx; + ir_node *n; + ir_node *value; + + be_foreach_definition(node, cls, value, + assert(req_->width >= 1); + values_defined += req_->width; + ); /* we need registers for the non-live argument values */ arity = get_irn_arity(node); - for(i = 0; i < arity; ++i) { + for (i = 0; i < arity; ++i) { ir_node *pred = get_irn_n(node, i); - if(arch_irn_consider_in_reg_alloc(arch_env, cls, pred) + if (arch_irn_consider_in_reg_alloc(cls, pred) && !ir_nodeset_contains(live_nodes, pred)) { - ++reload_values; + free_regs_needed += get_value_width(pred); } } - 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; - if(spills_needed <= 0) + 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 = xmalloc(node_count * sizeof(candidates[0])); + candidates = ALLOCAN(spill_candidate_t, n_live_nodes); /* construct array with spill candidates and calculate their costs */ - i = 0; + c = 0; foreach_ir_nodeset(live_nodes, n, iter) { - spill_candidate_t *candidate = & candidates[i]; + spill_candidate_t *candidate = & candidates[c]; assert(!bitset_is_set(spilled_nodes, get_irn_idx(n))); candidate->node = n; - candidate->costs = get_spill_costs(env, n); - ++i; + candidate->costs = get_spill_costs(n); + ++c; } - assert(i == node_count); + assert(c == 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) { - spill_candidate_t *candidate; - ir_node *cand_node; - int is_use; + while (spills_needed > 0) { + bool is_use = false; + spill_candidate_t *candidate; + ir_node *cand_node; - if (cand_idx >= node_count) { - panic("can't spill enough values for node %+F\n", node); + if (cand_idx >= n_live_nodes) { + panic("can't spill enough values for node %+F", node); } - candidate = &candidates[cand_idx]; cand_node = candidate->node; ++cand_idx; - if(arch_irn_is(arch_env, cand_node, dont_spill)) + if (arch_irn_is(skip_Proj_const(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) { ir_node *in = get_irn_n(node, i); - if(in == cand_node) { - is_use = 1; + if (in == cand_node) { + is_use = true; break; } } - if(is_use) { + if (is_use) continue; - } - spill_node(env, cand_node); + spill_node(cand_node); ir_nodeset_remove(live_nodes, cand_node); - --spills_needed; + spills_needed -= get_value_width(cand_node); } - - 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; + ir_node *value; + /* You must break out of your loop when hitting the first phi function. */ + assert(!is_Phi(node)); - /* 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"); + be_foreach_definition(node, cls, value, + ir_nodeset_remove(nodeset, value); + ); +} - if(arch_irn_consider_in_reg_alloc(arch_env, 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); + 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(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, op) && + !bitset_is_set(spilled_nodes, get_irn_idx(op))) { + ir_nodeset_insert(nodeset, op); } - } + } } static __attribute__((unused)) @@ -293,27 +281,27 @@ void print_nodeset(ir_nodeset_t *nodeset) * 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, spilled_phis, regpressure, phi_spills_needed; + ir_nodeset_t live_nodes; + ir_nodeset_iterator_t iter; + ir_node *node; + int n_phi_values_spilled; + int regpressure; + int live_nodes_pressure; + 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, 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-end... ", node)); - if(bitset_is_set(spilled_nodes, get_irn_idx(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 { @@ -321,79 +309,85 @@ void spill_block(ir_node *block, void *data) } } + /* walk schedule backwards and spill until register pressure is fine at + * each node */ sched_foreach_reverse(block, node) { - if(is_Phi(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); } - phi_count = 0; - 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)) + if (!is_Phi(node)) break; - ++phi_count; - if(bitset_is_set(spilled_nodes, get_irn_idx(node))) { - ++spilled_phis; + if (bitset_is_set(spilled_nodes, get_irn_idx(node))) { + n_phi_values_spilled += get_value_width(node); } } - regpressure = ir_nodeset_size(&live_nodes) + spilled_phis; - phi_spills_needed = regpressure - env->n_regs; + + live_nodes_pressure = 0; + foreach_ir_nodeset(&live_nodes, node, iter) { + live_nodes_pressure += get_value_width(node); + } + + /* calculate how many of the phis need to be spilled */ + regpressure = live_nodes_pressure + 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)) + if (!is_Phi(node)) break; - if(phi_spills_needed <= 0) + if (phi_spills_needed <= 0) break; - if(bitset_is_set(spilled_nodes, get_irn_idx(node))) { - be_spill_phi(env->spill_env, node); - --phi_spills_needed; - } + if (!bitset_is_set(spilled_nodes, get_irn_idx(node))) + continue; + + be_spill_phi(spill_env, node); + phi_spills_needed -= get_value_width(node); } assert(phi_spills_needed <= 0); ir_nodeset_destroy(&live_nodes); } -void be_spill_daemel(be_irg_t *birg, const arch_register_class_t *cls) +static void be_spill_daemel(ir_graph *irg, 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); - - if(n_regs == 0) + n_regs = be_get_n_allocatable_regs(irg, new_cls); + if (n_regs == 0) return; - be_liveness_assure_sets(be_assure_liveness(birg)); + be_liveness_assure_sets(be_assure_liveness(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)); + spill_env = be_new_spill_env(irg); + cls = new_cls; + lv = be_get_irg_liveness(irg); + 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); - be_insert_spills_reloads(env.spill_env); - - be_delete_spill_env(env.spill_env); + be_insert_spills_reloads(spill_env); + be_delete_spill_env(spill_env); } +BE_REGISTER_MODULE_CONSTRUCTOR(be_init_daemelspill) void be_init_daemelspill(void) { static be_spiller_t daemel_spiller = { @@ -401,7 +395,5 @@ 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);