X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbespill.c;h=2495cc7f3cd174c2696a2387cdf4e079f7fe9aa8;hb=9276447aec4972df060349e162f583c4898dfec8;hp=a6902bfbbd31d0543d09706141b7554e063612e7;hpb=e705a754ad5d92918739622a778dbdd067adb1a5;p=libfirm diff --git a/ir/be/bespill.c b/ir/be/bespill.c index a6902bfbb..2495cc7f3 100644 --- a/ir/be/bespill.c +++ b/ir/be/bespill.c @@ -1,9 +1,28 @@ /* - * Author: Daniel Grund, Sebastian Hack, Matthias Braun - * Date: 29.09.2005 - * Copyright: (c) Universitaet Karlsruhe - * Licence: This file protected by GPL - GNU GENERAL PUBLIC LICENSE. - * CVS-Id: $Id$ + * Copyright (C) 1995-2007 University of Karlsruhe. All right reserved. + * + * This file is part of libFirm. + * + * This file may be distributed and/or modified under the terms of the + * GNU General Public License version 2 as published by the Free Software + * Foundation and appearing in the file LICENSE.GPL included in the + * packaging of this file. + * + * Licensees holding valid libFirm Professional Edition licenses may use + * this file in accordance with the libFirm Commercial License. + * Agreement provided with the Software. + * + * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE + * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR + * PURPOSE. + */ + +/** + * @file + * @brief Main spill driver. + * @author Daniel Grund, Sebastian Hack, Matthias Braun + * @date 29.09.2005 + * @version $Id$ */ #ifdef HAVE_CONFIG_H #include "config.h" @@ -24,8 +43,8 @@ #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" @@ -37,9 +56,12 @@ #include "benodesets.h" #include "bespilloptions.h" #include "bestatevent.h" +#include "bessaconstr.h" +#include "beirg_t.h" +#include "beintlive_t.h" -// only rematerialise when costs are less than REMAT_COST_LIMIT -// TODO determine a good value here... +/* only rematerialise when costs are less than REMAT_COST_LIMIT */ +/* TODO determine a good value here... */ #define REMAT_COST_LIMIT 10 typedef struct _reloader_t reloader_t; @@ -75,7 +97,7 @@ struct _spill_env_t { 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 */ + ir_nodeset_t mem_phis; /**< set of all special spilled phis. allocated and freed separately */ DEBUG_ONLY(firm_dbg_module_t *dbg;) }; @@ -123,12 +145,12 @@ static spill_info_t *get_spillinfo(const spill_env_t *env, ir_node *value) { 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(be_irg_t *birg) { @@ -137,7 +159,7 @@ spill_env_t *be_new_spill_env(be_irg_t *birg) { env->irg = be_get_birg_irg(birg); env->birg = birg; env->arch_env = birg->main_env->arch_env; - env->mem_phis = pset_new_ptr_default(); + ir_nodeset_init(&env->mem_phis); // TODO, ask backend about costs..., or even ask backend whether we should // rematerialize... env->spill_cost = 8; @@ -149,7 +171,7 @@ spill_env_t *be_new_spill_env(be_irg_t *birg) { /* 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); } @@ -177,6 +199,9 @@ void be_add_remat(spill_env_t *env, ir_node *to_spill, ir_node *before, ir_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, @@ -220,14 +245,21 @@ void be_add_reload(spill_env_t *env, ir_node *to_spill, ir_node *before, 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")); } -static ir_node *get_reload_insertion_point(ir_node *block, int pos) { +/** + * Returns the point at which you can insert a node that should be executed + * before block @p block when coming from pred @p pos. + */ +static ir_node *get_block_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 - * (we don't need to check for phis as there can't be any in a block with only 1 pred) - */ + /* simply add the reload to the beginning of the block if we only have 1 + * predecessor. We don't need to check for phis as there can't be any in a + * block with only 1 pred. */ if(get_Block_n_cfgpreds(block) == 1) { assert(!is_Phi(sched_first(block))); return sched_first(block); @@ -244,12 +276,9 @@ static ir_node *get_reload_insertion_point(ir_node *block, int pos) { } if(!is_cfop(last)) { - ir_graph *irg = get_irn_irg(block); - ir_node *startblock = get_irg_start_block(irg); - last = sched_next(last); // last node must be a cfop, only exception is the start block - assert(last == startblock); + assert(last == get_irg_start_block(get_irn_irg(block))); } // add the reload before the (cond-)jump @@ -259,7 +288,7 @@ static ir_node *get_reload_insertion_point(ir_node *block, int pos) { 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); + ir_node *before = get_block_insertion_point(block, pos); be_add_reload(env, to_spill, before, reload_cls, allow_remat); } @@ -269,7 +298,7 @@ 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); @@ -297,9 +326,9 @@ void be_spill_phi(spill_env_t *env, ir_node *node) { */ /** - * Schedules a node after an instruction. (That is the place after all projs and phis - * that are scheduled after the instruction) - * This function also skips phi nodes at the beginning of a block + * Schedules a node after an instruction. That is the place after all projs and + * phis that are scheduled after the instruction. This function also skips phi + * nodes at the beginning of a block */ static void sched_add_after_insn(ir_node *sched_after, ir_node *node) { ir_node *next = sched_next(sched_after); @@ -325,27 +354,48 @@ 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 * - * (although rematerialization code should handle most of these cases - * this can still happen when spilling Phis) + * Normally reloads get simply rematerialized instead of spilled again; this + * can happen annyway when the reload is the pred of a phi to spill) */ - 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)) { - assert(0 && "Attempt to spill a node marked 'dont_spill'"); + assert(!(arch_irn_is(env->arch_env, to_spill, dont_spill) + && "Attempt to spill a node marked 'dont_spill'")); + + /* some backends have virtual noreg/unknown nodes that are not scheduled */ + if(!sched_is_scheduled(to_spill)) { + spillinfo->spill = new_NoMem(); + return; } + + /* + 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); @@ -369,6 +419,7 @@ 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) { @@ -384,17 +435,25 @@ 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, created PhiM %+F\n", phi, spillinfo->spill)); // rewire reloads from old_spill to phi - if(spillinfo->old_spill != NULL) { + if (spillinfo->old_spill != NULL) { const ir_edge_t *edge, *next; 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); + 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; @@ -415,7 +474,8 @@ 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)) { + + if (is_Phi(to_spill) && ir_nodeset_contains(&env->mem_phis, to_spill)) { spill_phi(env, spillinfo); } else { spill_irn(env, spillinfo); @@ -626,7 +686,7 @@ int be_get_reload_costs(spill_env_t *env, ir_node *to_spill, ir_node *before) { } 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); + ir_node *before = get_block_insertion_point(block, pos); return be_get_reload_costs(env, to_spill, before); } @@ -645,27 +705,38 @@ void be_insert_spills_reloads(spill_env_t *env) { 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_node(env, info); + } /* process each spilled node */ 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); + + DBG((env->dbg, LEVEL_1, "\nhandling all reloaders of %+F:\n", spilled_node)); /* go through all reloads for this spill */ for (rld = si->reloaders; rld; rld = rld->next) { - ir_node *new_val; + ir_node *copy; /* a reload is a "copy" of the original value */ if (rld->rematted_node != NULL) { - new_val = rld->rematted_node; + copy = rld->rematted_node; remats++; - sched_add_before(rld->reloader, new_val); - } - else if (be_do_remats && rld->allow_remat && check_remat_conditions(env, si->spilled_node, rld->reloader)) { - new_val = do_remat(env, si->spilled_node, rld->reloader); + 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 { + } else { /* make sure we have a spill */ if (si->spill == NULL) { spill_node(env, si); @@ -673,22 +744,40 @@ void be_insert_spills_reloads(spill_env_t *env) { } /* create a reload */ - new_val = be_reload(arch_env, si->reload_cls, rld->reloader, mode, si->spill); + 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->birg->dom_front, env->birg->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) { + be_ssa_construction_env_t senv; + /* be_lv_t *lv = be_get_birg_liveness(env->birg); */ + + be_ssa_construction_init(&senv, env->birg); + be_ssa_construction_add_copy(&senv, spilled_node); + be_ssa_construction_add_copies(&senv, copies, ARR_LEN(copies)); + be_ssa_construction_fix_users(&senv, spilled_node); - del_pset(values); +#if 0 + /* no need to enable this as long as we invalidate liveness + after this function... */ + be_ssa_construction_update_liveness_phis(&senv); + be_liveness_update(spilled_node); + len = ARR_LEN(copies); + for(i = 0; i < len; ++i) { + be_liveness_update(lv, copies[i]); + } +#endif + be_ssa_construction_destroy(&senv); + } + DEL_ARR_F(copies); si->reloaders = NULL; } @@ -701,6 +790,7 @@ void be_insert_spills_reloads(spill_env_t *env) { #endif /* FIRM_STATISTICS */ be_remove_dead_nodes_from_schedule(env->irg); - //be_liveness_recompute(env->birg->lv); + /* Matze: In theory be_ssa_construction should take care of the liveness... + * try to disable this again in the future */ be_invalidate_liveness(env->birg); }