X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbespill.c;h=62ffddc972fcd379fa5adf9c253982192d460784;hb=895edce679ee6434eb0c4f8b976e3f668bf2d48b;hp=fad86bc8b758c6f3ed18b179e2a8328e23e8122f;hpb=b71eb461afcc67cf09b606d42db1125b03e001e6;p=libfirm diff --git a/ir/be/bespill.c b/ir/be/bespill.c index fad86bc8b..62ffddc97 100644 --- a/ir/be/bespill.c +++ b/ir/be/bespill.c @@ -1,6 +1,8 @@ -/* - * Author: Daniel Grund, Sebastian Hack, Matthias Braun - * Date: 29.09.2005 +/** + * @file + * @author Daniel Grund, Sebastian Hack, Matthias Braun + * @date 29.09.2005 + * @version $Id$ * Copyright: (c) Universitaet Karlsruhe * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE. */ @@ -14,6 +16,7 @@ #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" @@ -22,8 +25,8 @@ #include "irgwalk.h" #include "array.h" #include "pdeq.h" -#include "unionfind.h" #include "execfreq.h" +#include "irnodeset.h" #include "belive_t.h" #include "besched_t.h" @@ -33,16 +36,21 @@ #include "bechordal_t.h" #include "bejavacoal.h" #include "benodesets.h" +#include "bespilloptions.h" +#include "bestatevent.h" +#include "beirgmod.h" // only rematerialise when costs are less than REMAT_COST_LIMIT // TODO determine a good value here... -#define REMAT_COST_LIMIT 20 +#define REMAT_COST_LIMIT 10 typedef struct _reloader_t reloader_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 */ }; typedef struct _spill_info_t { @@ -56,15 +64,20 @@ typedef struct _spill_info_t { /** 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 { - const arch_register_class_t *cls; const arch_env_t *arch_env; - const be_chordal_env_t *chordal_env; + ir_graph *irg; 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 */ + 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 */ + ir_nodeset_t mem_phis; /**< set of all special spilled phis. allocated and freed separately */ DEBUG_ONLY(firm_dbg_module_t *dbg;) }; @@ -78,6 +91,19 @@ static int cmp_spillinfo(const void *x, const void *y, size_t size) { 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) */ @@ -92,27 +118,32 @@ static spill_info_t *get_spillinfo(const spill_env_t *env, ir_node *value) { 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; } -DEBUG_ONLY( +#ifdef DEBUG_libfirm /* 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; } -) +#endif /* Creates a new spill environment. */ -spill_env_t *be_new_spill_env(const be_chordal_env_t *chordal_env) { +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->cls = chordal_env->cls; - env->chordal_env = chordal_env; - env->arch_env = env->chordal_env->birg->main_env->arch_env; - env->mem_phis = pset_new_ptr_default(); + env->irg = be_get_birg_irg(birg); + env->birg = birg; + env->arch_env = birg->main_env->arch_env; + ir_nodeset_init(&env->mem_phis); + // 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; } @@ -120,12 +151,12 @@ spill_env_t *be_new_spill_env(const be_chordal_env_t *chordal_env) { /* Deletes a spill environment. */ void be_delete_spill_env(spill_env_t *env) { del_set(env->spills); - del_pset(env->mem_phis); + ir_nodeset_destroy(&env->mem_phis); obstack_free(&env->obst, NULL); free(env); } -/** +/* * ____ _ ____ _ _ * | _ \| | __ _ ___ ___ | _ \ ___| | ___ __ _ __| |___ * | |_) | |/ _` |/ __/ _ \ | |_) / _ \ |/ _ \ / _` |/ _` / __| @@ -134,31 +165,72 @@ void be_delete_spill_env(spill_env_t *env) { * */ -void be_add_reload(spill_env_t *env, ir_node *to_spill, ir_node *before) { +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); + + /* 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; + + spill_info->reloaders = reloader; + + DBG((env->dbg, LEVEL_1, "creating spillinfo for %+F, will be rematerialized before %+F\n", + to_spill, before)); +} + +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; - assert(sched_is_scheduled(before)); - assert(arch_irn_consider_in_reg_alloc(env->arch_env, env->cls, to_spill)); - info = get_spillinfo(env, to_spill); - if(is_Phi(to_spill)) { + 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) { + + /* 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 } - rel = obstack_alloc(&env->obst, sizeof(rel[0])); - rel->reloader = before; - rel->next = info->reloaders; - info->reloaders = rel; + /* 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; + + DBG((env->dbg, LEVEL_1, "creating spillinfo for %+F, will be reloaded before %+F, may%s be rematerialized\n", + to_spill, before, allow_remat ? "" : " not")); } -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 @@ -166,8 +238,7 @@ void be_add_reload_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block, */ 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 */ @@ -179,10 +250,22 @@ void be_add_reload_on_edge(spill_env_t *env, ir_node *to_spill, ir_node *block, last = sched_prev(last); assert(!sched_is_end(last)); } - assert(is_cfop(last)); + + if(!is_cfop(last)) { + last = sched_next(last); + // last node must be a cfop, only exception is the start block + assert(last == get_irg_start_block(get_irn_irg(block))); + } // 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, + 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) { @@ -191,7 +274,7 @@ void be_spill_phi(spill_env_t *env, ir_node *node) { assert(is_Phi(node)); - pset_insert_ptr(env->mem_phis, node); + ir_nodeset_insert(&env->mem_phis, node); // create spillinfos for the phi arguments spill = get_spillinfo(env, node); @@ -203,6 +286,7 @@ void be_spill_phi(spill_env_t *env, ir_node *node) { // 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; } @@ -246,9 +330,10 @@ static void sched_add_after_insn(ir_node *sched_after, ir_node *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; + optimization_state_t opt; + ir_node *to_spill = spillinfo->spilled_node; - DBG((env->dbg, LEVEL_1, "%+F\n", to_spill)); + DBG((env->dbg, LEVEL_1, "spilling %+F ... ", 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 @@ -256,20 +341,32 @@ static void spill_irn(spill_env_t *env, spill_info_t *spillinfo) { * (although rematerialization code should handle most of these cases * this can still happen when spilling Phis) */ - if(be_is_Reload(to_spill)) { + if (be_is_Reload(to_spill)) { spillinfo->spill = get_irn_n(to_spill, be_pos_Reload_mem); + DB((env->dbg, LEVEL_1, "skip reload, using existing spill %+F\n", spillinfo->spill)); return; } if (arch_irn_is(env->arch_env, to_spill, dont_spill)) { - if (env->chordal_env->opts->vrfy_option == BE_CH_VRFY_WARN) - ir_fprintf(stderr, "Verify warning: spilling 'dont_spill' node %+F\n", to_spill); - else if (env->chordal_env->opts->vrfy_option == BE_CH_VRFY_ASSERT) - assert(0 && "Attempt to spill a node marked 'dont_spill'"); + assert(0 && "Attempt to spill a node marked 'dont_spill'"); } + /* + We switch on optimizations here to get CSE. This is needed as some backends + have some extra spill phases and we want to make use of those spills instead + of creating new ones. + */ + save_optimization_state(&opt); + set_optimize(1); spillinfo->spill = be_spill(env->arch_env, to_spill); - sched_add_after_insn(to_spill, spillinfo->spill); + restore_optimization_state(&opt); + if (! sched_is_scheduled(spillinfo->spill)) { + DB((env->dbg, LEVEL_1, "add spill %+F after %+F\n", spillinfo->spill, to_spill)); + sched_add_after_insn(to_spill, spillinfo->spill); + } + else { + DB((env->dbg, LEVEL_1, "re-using spill %+F after %+F\n", spillinfo->spill, to_spill)); + } } static void spill_node(spill_env_t *env, spill_info_t *spillinfo); @@ -293,12 +390,13 @@ static void spill_phi(spill_env_t *env, spill_info_t *spillinfo) { assert(is_Phi(phi)); + DBG((env->dbg, LEVEL_1, "spilling Phi %+F:\n", phi)); /* build a new PhiM */ ins = alloca(sizeof(ir_node*) * arity); for(i = 0; i < arity; ++i) { - ins[i] = get_irg_bad(env->chordal_env->irg); + ins[i] = get_irg_bad(env->irg); } - spillinfo->spill = new_r_Phi(env->chordal_env->irg, block, arity, ins, mode_M); + 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); @@ -308,15 +406,27 @@ static void spill_phi(spill_env_t *env, spill_info_t *spillinfo) { set_irn_n(spillinfo->spill, i, arg_info->spill); } + DBG((env->dbg, LEVEL_1, "... done spilling Phi %+F\n", phi)); // rewire reloads from old_spill to phi - if(spillinfo->old_spill != NULL) { + 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); + ir_node *old_spill = spillinfo->old_spill; + + DBG((env->dbg, LEVEL_1, "old spill found, rewiring reloads:\n")); + + foreach_out_edge_safe(old_spill, edge, next) { + ir_node *reload = get_edge_src_irn(edge); + int pos = get_edge_src_pos(edge); + + DBG((env->dbg, LEVEL_1, "\tset input %d of %+F to %+F\n", pos, reload, spillinfo->spill)); + assert(be_is_Reload(reload) || is_Phi(reload)); - set_irn_n(reload, get_edge_src_pos(edge), spillinfo->spill); + set_irn_n(reload, pos, spillinfo->spill); } + DBG((env->dbg, LEVEL_1, "\tset input of %+F to BAD\n", old_spill)); + set_irn_n(old_spill, be_pos_Spill_val, new_Bad()); + //sched_remove(old_spill); spillinfo->old_spill = NULL; } } @@ -335,7 +445,8 @@ static void spill_node(spill_env_t *env, spill_info_t *spillinfo) { return; to_spill = spillinfo->spilled_node; - if (is_Phi(to_spill) && pset_find_ptr(env->mem_phis, spillinfo->spilled_node)) { + assert(sched_is_scheduled(to_spill) && "Node to be spilled must be scheduled!"); + if (is_Phi(to_spill) && ir_nodeset_contains(&env->mem_phis, to_spill)) { spill_phi(env, spillinfo); } else { spill_irn(env, spillinfo); @@ -363,35 +474,43 @@ static int is_value_available(spill_env_t *env, ir_node *arg, ir_node *reloader) if(be_is_Spill(arg)) return 1; - if(arg == get_irg_frame(env->chordal_env->irg)) + 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. - * - * So we can only do this test for ignore registers (of our register class) */ - if(arch_get_irn_reg_class(env->arch_env, arg, -1) == env->chordal_env->cls - && arch_irn_is(env->arch_env, arg, ignore)) { - int i, arity; - /* 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->chordal_env->lv, reloader, arg)) { - return 1; - } + /* 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; - } + 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; } @@ -466,7 +585,7 @@ static int check_remat_conditions_costs(spill_env_t *env, ir_node *spilled, ir_n } 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; } @@ -481,9 +600,15 @@ static int check_remat_conditions(spill_env_t *env, ir_node *spilled, ir_node *r static ir_node *do_remat(spill_env_t *env, ir_node *spilled, ir_node *reloader) { int i, arity; ir_node *res; - ir_node *bl = get_nodes_block(reloader); + 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); @@ -496,22 +621,46 @@ static ir_node *do_remat(spill_env_t *env, ir_node *spilled, ir_node *reloader) } /* create a copy of the node */ - res = new_ir_node(get_irn_dbg_info(spilled), env->chordal_env->irg, bl, + 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 before reloader %+F\n", res, reloader)); + DBG((env->dbg, LEVEL_1, "Insert remat %+F of %+F before reloader %+F\n", res, spilled, reloader)); /* insert in schedule */ - assert(!is_Block(reloader)); sched_add_before(reloader, res); return res; } +int be_get_reload_costs(spill_env_t *env, ir_node *to_spill, ir_node *before) { + spill_info_t *spill_info; + + 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; + + 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); +} + /* * ___ _ ____ _ _ * |_ _|_ __ ___ ___ _ __| |_ | _ \ ___| | ___ __ _ __| |___ @@ -523,44 +672,85 @@ static ir_node *do_remat(spill_env_t *env, ir_node *spilled, ir_node *reloader) void be_insert_spills_reloads(spill_env_t *env) { const arch_env_t *arch_env = env->arch_env; - spill_info_t *si; + int remats = 0; + int reloads = 0; + int spills = 0; + spill_info_t *si; + ir_nodeset_iterator_t iter; + ir_node *node; + + /* create all phi-ms first, this is needed so, that phis, hanging on + spilled phis work correctly */ + foreach_ir_nodeset(&env->mem_phis, node, iter) { + spill_info_t *info = get_spillinfo(env, node); + spill_phi(env, info); + } /* 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)) { + 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); + ir_node *spilled_node = si->spilled_node; + ir_mode *mode = get_irn_mode(spilled_node); + ir_node **copies = NEW_ARR_F(ir_node*, 0); - /* go through all reloads for this spill */ - for(rld = si->reloaders; rld; rld = rld->next) { - ir_node *new_val; + DBG((env->dbg, LEVEL_1, "\nhandling all reloaders of %+F:\n", spilled_node)); - if (check_remat_conditions(env, si->spilled_node, rld->reloader)) { - new_val = do_remat(env, si->spilled_node, rld->reloader); + /* go through all reloads for this spill */ + for (rld = si->reloaders; rld; rld = rld->next) { + ir_node *copy; /* a reaload is a "copy" of the original value */ + + if (rld->rematted_node != NULL) { + copy = rld->rematted_node; + remats++; + sched_add_before(rld->reloader, copy); + } else if (be_do_remats && rld->allow_remat && + check_remat_conditions(env, spilled_node, rld->reloader)) { + copy = do_remat(env, spilled_node, rld->reloader); + remats++; } else { /* make sure we have a spill */ - spill_node(env, si); - - /* do a reload */ - new_val = be_reload(arch_env, env->cls, rld->reloader, mode, si->spill); + if (si->spill == NULL) { + spill_node(env, si); + spills++; + } + + /* create a reload */ + copy = 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); + DBG((env->dbg, LEVEL_1, " %+F of %+F before %+F\n", + copy, spilled_node, rld->reloader)); + ARR_APP1(ir_node*, copies, copy); } - if(pset_count(values) > 0) { - /* introduce copies, rewire the uses */ - pset_insert_ptr(values, si->spilled_node); - be_ssa_constr_set_ignore(env->chordal_env->dom_front, env->chordal_env->lv, values, env->mem_phis); + /* if we had any reloads or remats, then we need to reconstruct the + * SSA form for the spilled value */ + if (ARR_LEN(copies) > 0) { + /* Matze: used mem_phis as ignore uses in the past, I don't see how + one of the mem_phis can be a use of the spilled value... + so I changed this to NULL now */ + be_ssa_construction( + be_get_birg_dom_front(env->birg), + be_get_birg_liveness(env->birg), + spilled_node, ARR_LEN(copies), copies, + NULL, 0); } - del_pset(values); - + DEL_ARR_F(copies); si->reloaders = NULL; } - be_remove_dead_nodes_from_schedule(env->chordal_env->irg); - be_liveness_recompute(env->chordal_env->lv); +#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); + /* Matze: In theory be_ssa_construction should take care of the livenes... + * try to disable this again in the future */ + be_invalidate_liveness(env->birg); }