X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbeblocksched.c;h=b8de83bb1eeb051a02c2f2158386882b69c7ca58;hb=2cb4a701f143339e07259cf7331c670f5584de63;hp=c4096777ec0d0e40ac0fa072ad77f6e468f1baa1;hpb=79ed89a676afd08eb739330d46b85b1d1532aec1;p=libfirm diff --git a/ir/be/beblocksched.c b/ir/be/beblocksched.c index c4096777e..b8de83bb1 100644 --- a/ir/be/beblocksched.c +++ b/ir/be/beblocksched.c @@ -1,5 +1,5 @@ /* - * 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. * @@ -23,10 +23,18 @@ * @author Matthias Braun, Christoph Mallon * @date 27.09.2006 * @version $Id$ + * + * The goals of the greedy (and ILP) algorithm here works by assuming that + * we want to change as many jumps to fallthroughs as possible (executed jumps + * actually, we have to look at the execution frequencies). The algorithms + * do this by collecting execution frequencies of all branches (which is easily + * possible when all critical edges are split) then removes critical edges where + * possible as we don't need and want them anymore now. The algorithms then try + * to change as many edges to fallthroughs as possible, this is done by setting + * a next and prev pointers on blocks. The greedy algorithm sorts the edges by + * execution frequencies and tries to transform them to fallthroughs in this order */ -#ifdef HAVE_CONFIG_H #include "config.h" -#endif #include "beblocksched.h" @@ -48,6 +56,10 @@ #include "beirgmod.h" #include "bemodule.h" #include "be.h" +#include "error.h" + +#include "lc_opts.h" +#include "lc_opts_enum.h" #ifdef WITH_ILP #include @@ -57,21 +69,13 @@ DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;) typedef enum _blocksched_algos_t { - BLOCKSCHED_NAIV, BLOCKSCHED_EXTBB, BLOCKSCHED_GREEDY, BLOCKSCHED_ILP + BLOCKSCHED_NAIV, BLOCKSCHED_GREEDY, BLOCKSCHED_ILP } blocksched_algos_t; static int algo = BLOCKSCHED_GREEDY; - -#ifdef WITH_LIBCORE - -#include -#include -#include - static const lc_opt_enum_int_items_t blockschedalgo_items[] = { { "naiv", BLOCKSCHED_NAIV }, - { "extbb", BLOCKSCHED_EXTBB }, { "greedy", BLOCKSCHED_GREEDY }, #ifdef WITH_ILP { "ilp", BLOCKSCHED_ILP }, @@ -87,7 +91,6 @@ static const lc_opt_table_entry_t be_blocksched_options[] = { LC_OPT_ENT_ENUM_INT ("algo", "the block scheduling algorithm", &algo_var), LC_OPT_LAST }; -#endif /* WITH_LIBCORE */ /* * ____ _ @@ -98,28 +101,35 @@ static const lc_opt_table_entry_t be_blocksched_options[] = { * |___/ */ -typedef struct _blocksched_entry_t { - ir_node *block; - struct _blocksched_entry_t *next; - struct _blocksched_entry_t *prev; -} blocksched_entry_t; +typedef struct blocksched_entry_t blocksched_entry_t; +struct blocksched_entry_t { + ir_node *block; + blocksched_entry_t *next; + blocksched_entry_t *prev; +}; -typedef struct _edge_t { +typedef struct edge_t edge_t; +struct edge_t { ir_node *block; /**< source block */ int pos; /**< number of cfg predecessor (target) */ double execfreq; /**< the frequency */ - int highest_execfreq; /**< flag that indicates whether this edge is the edge with the highest - execfreq pointing away from this block */ -} edge_t; + double outedge_penalty_freq; /**< for edges leaving the loop this is the + penality when we make them a + fallthrough. */ + int highest_execfreq; /**< flag that indicates whether this edge is + the edge with the highest execfreq pointing + away from this block */ +}; -typedef struct _blocksched_env_t { +typedef struct blocksched_env_t blocksched_env_t; +struct blocksched_env_t { ir_graph *irg; struct obstack *obst; ir_exec_freq *execfreqs; edge_t *edges; pdeq *worklist; int blockcount; -} blocksched_env_t; +}; /** * Collect cfg frequencies of all edges between blocks. @@ -131,22 +141,40 @@ static void collect_egde_frequency(ir_node *block, void *data) int arity; edge_t edge; blocksched_entry_t *entry; + ir_loop *loop; + + memset(&edge, 0, sizeof(edge)); - entry = obstack_alloc(env->obst, sizeof(entry[0])); + entry = obstack_alloc(env->obst, sizeof(entry[0])); + memset(entry, 0, sizeof(*entry)); entry->block = block; - entry->next = NULL; - entry->prev = NULL; set_irn_link(block, entry); - if (block == get_irg_start_block(env->irg)) - return; + loop = get_irn_loop(block); arity = get_Block_n_cfgpreds(block); - if (arity == 1) { + if (arity == 0) { + /* must be the start block (or end-block for endless loops), + * everything else is dead code and should be removed by now */ + assert(block == get_irg_start_block(env->irg) + || block == get_irg_end_block(env->irg)); + /* nothing to do here */ + return; + } else if (arity == 1) { + ir_node *pred_block = get_Block_cfgpred_block(block, 0); + ir_loop *pred_loop = get_irn_loop(pred_block); + float freq = get_block_execfreq(env->execfreqs, block); + + /* is it an edge leaving a loop */ + if (get_loop_depth(pred_loop) > get_loop_depth(loop)) { + float pred_freq = get_block_execfreq(env->execfreqs, pred_block); + edge.outedge_penalty_freq = -(pred_freq - freq); + } + edge.block = block; edge.pos = 0; - edge.execfreq = get_block_execfreq(env->execfreqs, block); + edge.execfreq = freq; edge.highest_execfreq = 1; ARR_APP1(edge_t, env->edges, edge); } else { @@ -185,27 +213,54 @@ static int cmp_edges(const void *d1, const void *d2) return QSORT_CMP(e2->execfreq, e1->execfreq); } +static int cmp_edges_outedge_penalty(const void *d1, const void *d2) +{ + const edge_t *e1 = d1; + const edge_t *e2 = d2; + /* reverse sorting as penalties are negative */ + return QSORT_CMP(e1->outedge_penalty_freq, e2->outedge_penalty_freq); +} + +static void clear_loop_links(ir_loop *loop) +{ + int i, n; + + set_loop_link(loop, NULL); + n = get_loop_n_elements(loop); + for (i = 0; i < n; ++i) { + loop_element elem = get_loop_element(loop, i); + if (*elem.kind == k_ir_loop) { + clear_loop_links(elem.son); + } + } +} + static void coalesce_blocks(blocksched_env_t *env) { int i; int edge_count = ARR_LEN(env->edges); + edge_t *edges = env->edges; + + /* sort interblock edges by execution frequency */ + qsort(edges, ARR_LEN(edges), sizeof(edges[0]), cmp_edges); /* run1: only look at jumps */ for (i = 0; i < edge_count; ++i) { - const edge_t *edge = &env->edges[i]; + const edge_t *edge = &edges[i]; ir_node *block = edge->block; + int pos = edge->pos; ir_node *pred_block; blocksched_entry_t *entry, *pred_entry; - /* the block might have been removed already... */ - if (is_Bad(get_Block_cfgpred(block, 0))) - continue; - /* only check edge with highest frequency */ if (! edge->highest_execfreq) continue; - pred_block = get_Block_cfgpred_block(block, edge->pos); + /* the block might have been removed already... */ + if (is_Bad(get_Block_cfgpred(block, 0))) + continue; + + pred_block = get_Block_cfgpred_block(block, pos); entry = get_irn_link(block); pred_entry = get_irn_link(pred_block); @@ -217,24 +272,76 @@ static void coalesce_blocks(blocksched_env_t *env) continue; /* schedule the 2 blocks behind each other */ - DBG((dbg, LEVEL_1, "Coalesce (Jump) %+F -> %+F (%.3g)\n", + DB((dbg, LEVEL_1, "Coalesce (Jump) %+F -> %+F (%.3g)\n", pred_entry->block, entry->block, edge->execfreq)); pred_entry->next = entry; entry->prev = pred_entry; } - /* run2: remaining edges */ + /* run2: pick loop fallthroughs */ + clear_loop_links(get_irg_loop(env->irg)); + + qsort(edges, ARR_LEN(edges), sizeof(edges[0]), cmp_edges_outedge_penalty); for (i = 0; i < edge_count; ++i) { - const edge_t *edge = &env->edges[i]; + const edge_t *edge = &edges[i]; ir_node *block = edge->block; + int pos = edge->pos; ir_node *pred_block; blocksched_entry_t *entry, *pred_entry; + ir_loop *loop; + ir_loop *outer_loop; + + /* already seen all loop outedges? */ + if (edge->outedge_penalty_freq == 0) + break; /* the block might have been removed already... */ - if (is_Bad(get_Block_cfgpred(block, 0))) + if (is_Bad(get_Block_cfgpred(block, pos))) + continue; + + pred_block = get_Block_cfgpred_block(block, pos); + entry = get_irn_link(block); + pred_entry = get_irn_link(pred_block); + + if (pred_entry->next != NULL || entry->prev != NULL) + continue; + + /* we want at most 1 outedge fallthrough per loop */ + loop = get_irn_loop(pred_block); + if (get_loop_link(loop) != NULL) + continue; + + /* schedule the 2 blocks behind each other */ + DB((dbg, LEVEL_1, "Coalesce (Loop Outedge) %+F -> %+F (%.3g)\n", + pred_entry->block, entry->block, edge->execfreq)); + pred_entry->next = entry; + entry->prev = pred_entry; + + /* all loops left have an outedge now */ + outer_loop = get_irn_loop(block); + do { + /* we set loop link to loop to mark it */ + set_loop_link(loop, loop); + loop = get_loop_outer_loop(loop); + } while (loop != outer_loop); + } + + /* sort interblock edges by execution frequency */ + qsort(edges, ARR_LEN(edges), sizeof(edges[0]), cmp_edges); + + /* run3: remaining edges */ + for (i = 0; i < edge_count; ++i) { + const edge_t *edge = &edges[i]; + ir_node *block = edge->block; + int pos = edge->pos; + ir_node *pred_block; + blocksched_entry_t *entry, *pred_entry; + + /* the block might have been removed already... */ + if (is_Bad(get_Block_cfgpred(block, pos))) continue; - pred_block = get_Block_cfgpred_block(block, edge->pos); + pred_block = get_Block_cfgpred_block(block, pos); entry = get_irn_link(block); pred_entry = get_irn_link(pred_block); @@ -243,7 +350,7 @@ static void coalesce_blocks(blocksched_env_t *env) continue; /* schedule the 2 blocks behind each other */ - DBG((dbg, LEVEL_1, "Coalesce (CondJump) %+F -> %+F (%.3g)\n", + DB((dbg, LEVEL_1, "Coalesce (CondJump) %+F -> %+F (%.3g)\n", pred_entry->block, entry->block, edge->execfreq)); pred_entry->next = entry; entry->prev = pred_entry; @@ -258,13 +365,12 @@ static void pick_block_successor(blocksched_entry_t *entry, blocksched_env_t *en const ir_edge_t *edge; double best_succ_execfreq; - if (irn_visited(block)) + if (irn_visited_else_mark(block)) return; env->blockcount++; - mark_irn_visited(block); - DBG((dbg, LEVEL_1, "Pick succ of %+F\n", block)); + DB((dbg, LEVEL_1, "Pick succ of %+F\n", block)); /* put all successors into the worklist */ foreach_block_succ(block, edge) { @@ -289,7 +395,7 @@ static void pick_block_successor(blocksched_entry_t *entry, blocksched_env_t *en if (irn_visited(succ_entry->block)) continue; - DBG((dbg, LEVEL_1, "Put %+F into worklist\n", succ_entry->block)); + DB((dbg, LEVEL_1, "Put %+F into worklist\n", succ_entry->block)); pdeq_putr(env->worklist, succ_entry->block); } @@ -298,7 +404,7 @@ static void pick_block_successor(blocksched_entry_t *entry, blocksched_env_t *en return; } - DBG((dbg, LEVEL_1, "deciding...\n")); + DB((dbg, LEVEL_1, "deciding...\n")); best_succ_execfreq = -1; /* no successor yet: pick the successor block with the highest execution @@ -323,11 +429,11 @@ static void pick_block_successor(blocksched_entry_t *entry, blocksched_env_t *en } if (succ == NULL) { - DBG((dbg, LEVEL_1, "pick from worklist\n")); + DB((dbg, LEVEL_1, "pick from worklist\n")); do { if (pdeq_empty(env->worklist)) { - DBG((dbg, LEVEL_1, "worklist empty\n")); + DB((dbg, LEVEL_1, "worklist empty\n")); return; } succ = pdeq_getl(env->worklist); @@ -347,7 +453,7 @@ static blocksched_entry_t *finish_block_schedule(blocksched_env_t *env) ir_node *startblock = get_irg_start_block(irg); blocksched_entry_t *entry = get_irn_link(startblock); - set_using_visited(irg); + ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED); inc_irg_visited(irg); env->worklist = new_pdeq(); @@ -355,7 +461,7 @@ static blocksched_entry_t *finish_block_schedule(blocksched_env_t *env) assert(pdeq_empty(env->worklist)); del_pdeq(env->worklist); - clear_using_visited(irg); + ir_free_resources(irg, IR_RESOURCE_IRN_VISITED); return entry; } @@ -369,12 +475,12 @@ static ir_node **create_blocksched_array(blocksched_env_t *env, blocksched_entry (void) env; block_list = NEW_ARR_D(ir_node *, obst, count); - DBG((dbg, LEVEL_1, "Blockschedule:\n")); + DB((dbg, LEVEL_1, "Blockschedule:\n")); for (entry = first; entry != NULL; entry = entry->next) { assert(i < count); block_list[i++] = entry->block; - DBG((dbg, LEVEL_1, "\t%+F\n", entry->block)); + DB((dbg, LEVEL_1, "\t%+F\n", entry->block)); } assert(i == count); @@ -397,12 +503,14 @@ static ir_node **create_block_schedule_greedy(ir_graph *irg, ir_exec_freq *execf env.worklist = NULL; env.blockcount = 0; + /* make sure loopinfo is up-to-date */ + if (! (get_irg_loopinfo_state(irg) & loopinfo_cf_consistent)) { + construct_cf_backedges(irg); + } + // collect edge execution frequencies irg_block_walk_graph(irg, collect_egde_frequency, NULL, &env); - // sort interblock edges by execution frequency - qsort(env.edges, ARR_LEN(env.edges), sizeof(env.edges[0]), cmp_edges); - (void)be_remove_empty_blocks(irg); if (algo != BLOCKSCHED_NAIV) @@ -494,7 +602,6 @@ static void collect_egde_frequency_ilp(ir_node *block, void *data) } else { int i; - int *edgenums = alloca(sizeof(edgenums[0]) * arity); snprintf(name, sizeof(name), "block_in_constr_%ld", get_irn_node_nr(block)); cst = lpp_add_cst_uniq(env->lpp, name, lpp_greater, arity - 1); @@ -533,7 +640,7 @@ static void coalesce_blocks_ilp(blocksched_ilp_env_t *env) pred = get_Block_cfgpred_block(block, edge->pos); entry = get_irn_link(pred); - DBG((dbg, LEVEL_1, "Adding out cst to %+F from %+F,%d\n", + DB((dbg, LEVEL_1, "Adding out cst to %+F from %+F,%d\n", pred, block, edge->pos)); lpp_set_factor_fast(env->lpp, entry->out_cst, edge->ilpvar, 1.0); } @@ -617,107 +724,6 @@ static ir_node **create_block_schedule_ilp(ir_graph *irg, ir_exec_freq *execfreq } #endif /* WITH_ILP */ -/* - * _____ _ ____ ____ - * | ____|_ _| |_| __ )| __ ) - * | _| \ \/ / __| _ \| _ \ - * | |___ > <| |_| |_) | |_) | - * |_____/_/\_\\__|____/|____/ - * - */ - -/** A simple forward single linked list. */ -typedef struct { - ir_node *start; /**< start of the list */ - ir_node *end; /**< last block in the list */ - unsigned n_blks; /**< number of blocks in the list */ -} anchor; - -static void add_block(anchor *list, ir_node *block) { - if (list->start == NULL) { - list->start = block; - list->end = block; - } else { - set_irn_link(list->end, block); - list->end = block; - } - - list->n_blks++; -} - -static void create_block_list(ir_node *leader_block, anchor *list) { - int i; - const ir_edge_t *edge; - ir_node *block = NULL; - ir_extblk *extbb = get_Block_extbb(leader_block); - - if (extbb_visited(extbb)) - return; - mark_extbb_visited(extbb); - - for (i = 0; i < get_extbb_n_blocks(extbb); ++i) { - block = get_extbb_block(extbb, i); - add_block(list, block); - } - - assert(block != NULL); - - /* pick successor extbbs */ - foreach_block_succ(block, edge) { - ir_node *succ = get_edge_src_irn(edge); - create_block_list(succ, list); - } - - for (i = 0; i < get_extbb_n_blocks(extbb) - 1; ++i) { - block = get_extbb_block(extbb, i); - - foreach_block_succ(block, edge) { - ir_node *succ = get_edge_src_irn(edge); - create_block_list(succ, list); - } - } -} - -void compute_extbb_execfreqs(ir_graph *irg, ir_exec_freq *execfreqs); - -/* - * Calculates a block schedule. The schedule is stored as a linked - * list starting at the start_block of the irg. - */ -static ir_node **create_extbb_block_schedule(ir_graph *irg, ir_exec_freq *execfreqs) -{ - anchor list; - ir_node **blk_list, *b, *n; - unsigned i; - - /* schedule extended basic blocks */ - compute_extbb_execfreqs(irg, execfreqs); - //compute_extbb(irg); - - list.start = NULL; - list.end = NULL; - list.n_blks = 0; - - set_using_irn_link(irg); - set_using_visited(irg); - inc_irg_block_visited(irg); - - create_block_list(get_irg_start_block(irg), &list); - - /** create an array, so we can go forward and backward */ - blk_list = NEW_ARR_D(ir_node *, irg->obst,list.n_blks); - - for (i = 0, b = list.start; b; b = n, ++i) { - n = get_irn_link(b); - blk_list[i] = b; - } - - clear_using_irn_link(irg); - clear_using_visited(irg); - - return blk_list; -} - /* * __ __ _ * | \/ | __ _(_)_ __ @@ -728,12 +734,11 @@ static ir_node **create_extbb_block_schedule(ir_graph *irg, ir_exec_freq *execfr */ void be_init_blocksched(void) { -#ifdef WITH_LIBCORE lc_opt_entry_t *be_grp = lc_opt_get_grp(firm_opt_get_root(), "be"); lc_opt_entry_t *blocksched_grp = lc_opt_get_grp(be_grp, "blocksched"); lc_opt_add_table(blocksched_grp, be_blocksched_options); -#endif + FIRM_DBG_REGISTER(dbg, "firm.be.blocksched"); } @@ -745,14 +750,12 @@ ir_node **be_create_block_schedule(ir_graph *irg, ir_exec_freq *execfreqs) case BLOCKSCHED_GREEDY: case BLOCKSCHED_NAIV: return create_block_schedule_greedy(irg, execfreqs); - case BLOCKSCHED_EXTBB: - return create_extbb_block_schedule(irg, execfreqs); #ifdef WITH_ILP case BLOCKSCHED_ILP: return create_block_schedule_ilp(irg, execfreqs); #endif /* WITH_ILP */ } - assert(0 && "unknown blocksched algo"); + panic("unknown blocksched algo"); return NULL; }