X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fbe%2Fbeirgmod.c;h=bf6506c110ac6e0a4329d9b31b3bc5ffa3fa46b4;hb=82eea1b6b7887bdc834affa49038734e42012395;hp=1f252d8eb46561f3ee9c9a087f1e0f3b2257db0a;hpb=2c6ff30b49af45737d5a01ed06c10763166ebb7b;p=libfirm diff --git a/ir/be/beirgmod.c b/ir/be/beirgmod.c index 1f252d8eb..bf6506c11 100644 --- a/ir/be/beirgmod.c +++ b/ir/be/beirgmod.c @@ -1,6 +1,34 @@ -#ifdef HAVE_CONFIG_H +/* + * Copyright (C) 1995-2008 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 Backend IRG modification routines. + * @author Sebastian Hack, Daniel Grund, Matthias Braun, Christian Wuerdig + * @date 04.05.2005 + * + * This file contains the following IRG modifications for be routines: + * - insertion of Perm nodes + * - empty block elimination + * - a simple dead node elimination (set inputs of unreachable nodes to BAD) + */ #include "config.h" -#endif #include @@ -10,514 +38,311 @@ #include "pmap.h" #include "util.h" #include "debug.h" +#include "error.h" +#include "xmalloc.h" #include "irflag_t.h" #include "ircons_t.h" #include "irnode_t.h" +#include "ircons_t.h" #include "irmode_t.h" #include "irdom_t.h" #include "iredges_t.h" +#include "irgraph_t.h" #include "irgopt.h" +#include "irgmod.h" +#include "irprintf.h" +#include "irgwalk.h" #include "be_t.h" +#include "bechordal_t.h" #include "bearch.h" -#include "besched_t.h" +#include "besched.h" #include "belive_t.h" -#include "benode_t.h" - +#include "benode.h" +#include "beutil.h" +#include "beinsn_t.h" +#include "bessaconstr.h" +#include "beirg.h" #include "beirgmod.h" +#include "bemodule.h" -#define DBG_MODULE firm_dbg_register("firm.be.irgmod") - -struct _dom_front_info_t { - pmap *df_map; -}; +DEBUG_ONLY(static firm_dbg_module_t *dbg = NULL;) -/** - * A wrapper for get_Block_idom. - * This function returns the block itself, if the block is the start - * block. Returning NULL would make any != comparison true which - * suggests, that the start block is dominated by some other node. - * @param bl The block. - * @return The immediate dominator of the block. - */ -static INLINE ir_node *get_idom(ir_node *bl) -{ - ir_node *idom = get_Block_idom(bl); - return idom == NULL ? bl : idom; -} - -static void compute_df_local(ir_node *bl, void *data) +static int cmp_node_nr(const void *a, const void *b) { - pmap *df_map = ((dom_front_info_t *) data)->df_map; - ir_node *idom = get_Block_idom(bl); - pset *df = pmap_get(df_map, bl); - int i, n; - - /* - * In the case that the immediate dominator is NULL, the - * block is the start block and its immediate dominator - * must be itself, else it is inserted into its own - * dominance frontier. - */ - if(idom == NULL) - idom = bl; - - /* - * Create a new dom frot set for this node, - * if none exists. - */ - if(!df) - pmap_insert(df_map, bl, pset_new_ptr(16)); - - for(i = 0, n = get_irn_arity(bl); i < n; ++i) { - - /* The predecessor block */ - ir_node *pred = get_nodes_block(get_irn_n(bl, i)); - - /* The dominance frontier set of the predecessor. */ - pset *df = pmap_get(df_map, pred); - if(!df) { - df = pset_new_ptr(16); - pmap_insert(df_map, pred, df); - } - - assert(df && "dom front set must have been created for this node"); - - if(pred != idom && bl) - pset_insert_ptr(df, bl); - } + ir_node **p1 = (ir_node**)a; + ir_node **p2 = (ir_node**)b; + long n1 = get_irn_node_nr(*p1); + long n2 = get_irn_node_nr(*p2); + return (n1>n2) - (n1df_map; - ir_node *y; +/* + ___ _ ____ + |_ _|_ __ ___ ___ _ __| |_ | _ \ ___ _ __ _ __ ___ + | || '_ \/ __|/ _ \ '__| __| | |_) / _ \ '__| '_ ` _ \ + | || | | \__ \ __/ | | |_ | __/ __/ | | | | | | | + |___|_| |_|___/\___|_| \__| |_| \___|_| |_| |_| |_| - for(y = get_Block_dominated_first(bl); y; y = get_Block_dominated_next(y)) { - ir_node *w; - pset *df = pmap_get(df_map, y); +*/ - for(w = pset_first(df); w; w = pset_next(df)) - if(!block_dominates(bl, w) || bl == w) - pset_insert_ptr(df, w); - } -} - -static void compute_df(ir_node *n, pmap *df_map) +ir_node *insert_Perm_before(ir_graph *irg, const arch_register_class_t *cls, + ir_node *pos) { - ir_node *y, *c; - const ir_edge_t *edge; - pset *df = pset_new_ptr_default(); - - /* Add local dominance frontiers */ - foreach_block_succ(n, edge) { - ir_node *y = edge->src; - - if(get_idom(y) != n) - pset_insert_ptr(df, y); - } - - /* - * Go recursively down the dominance tree and add all blocks - * int the dominance frontiers of the children, which are not - * dominated by the given block. - */ - for(c = get_Block_dominated_first(n); c; c = get_Block_dominated_next(c)) { - pset *df_c; - ir_node *w; - - compute_df(c, df_map); - df_c = pmap_get(df_map, c); - - for(w = pset_first(df_c); w; w = pset_next(df_c)) { - if(!block_dominates(n, w)) - pset_insert_ptr(df, w); - } - } - - pmap_insert(df_map, n, df); - + be_lv_t *lv = be_get_irg_liveness(irg); + ir_nodeset_t live; + + ir_node *perm, **nodes; + size_t i, n; + + DBG((dbg, LEVEL_1, "Insert Perm before: %+F\n", pos)); + + ir_nodeset_init(&live); + be_liveness_nodes_live_before(lv, cls, pos, &live); + + n = ir_nodeset_size(&live); + if (n == 0) { + ir_nodeset_destroy(&live); + return NULL; + } + + nodes = XMALLOCN(ir_node*, n); + + DBG((dbg, LEVEL_1, "live:\n")); + i = 0; + foreach_ir_nodeset(&live, irn, iter) { + DBG((dbg, LEVEL_1, "\t%+F\n", irn)); + nodes[i] = irn; + i++; + } + ir_nodeset_destroy(&live); + /* make the input order deterministic */ + qsort(nodes, n, sizeof(nodes[0]), cmp_node_nr); + + ir_node *const bl = get_nodes_block(pos); + perm = be_new_Perm(cls, bl, n, nodes); + sched_add_before(pos, perm); + free(nodes); + + for (i = 0; i < n; ++i) { + ir_node *perm_op = get_irn_n(perm, i); + be_ssa_construction_env_t senv; + + ir_mode *mode = get_irn_mode(perm_op); + ir_node *proj = new_r_Proj(perm, mode, i); + + be_ssa_construction_init(&senv, irg); + be_ssa_construction_add_copy(&senv, perm_op); + be_ssa_construction_add_copy(&senv, proj); + be_ssa_construction_fix_users(&senv, perm_op); + be_ssa_construction_update_liveness_phis(&senv, lv); + be_liveness_update(lv, perm_op); + be_liveness_update(lv, proj); + be_ssa_construction_destroy(&senv); + } + + return perm; } -dom_front_info_t *be_compute_dominance_frontiers(ir_graph *irg) -{ - dom_front_info_t *info = malloc(sizeof(*info)); - - edges_assure(irg); - info->df_map = pmap_create(); - compute_df(get_irg_start_block(irg), info->df_map); - -#if 0 - /* - * This must be called as a post walker, since the dom front sets - * of all predecessors must be created when a block is reached. - */ - dom_tree_walk_irg(irg, NULL, compute_df_local, info); - dom_tree_walk_irg(irg, NULL, compute_df_up, info); -#endif - return info; -} +static int blocks_removed; -void be_free_dominance_frontiers(dom_front_info_t *info) +/** + * Post-block-walker: Find blocks containing only one jump and + * remove them. + */ +static void remove_empty_block(ir_node *block) { - pmap_entry *ent; - - for(ent = pmap_first(info->df_map); ent; ent = pmap_next(info->df_map)) - del_pset(ent->value); - - pmap_destroy(info->df_map); - free(info); + int i; + int arity; + ir_node *pred; + ir_node *succ_block; + ir_node *jump = NULL; + ir_graph *irg = get_irn_irg(block); + ir_entity *entity; + + if (irn_visited_else_mark(block)) + return; + + if (get_Block_n_cfgpreds(block) != 1) + goto check_preds; + + sched_foreach(block, node) { + if (! is_Jmp(node) + && !(arch_get_irn_flags(node) & arch_irn_flags_simple_jump)) + goto check_preds; + if (jump != NULL) { + /* we should never have 2 jumps in a block */ + panic("found 2 jumps in a block"); + } + jump = node; + } + + if (jump == NULL) + goto check_preds; + + entity = get_Block_entity(block); + pred = get_Block_cfgpred(block, 0); + succ_block = NULL; + foreach_out_edge_safe(jump, edge) { + int pos = get_edge_src_pos(edge); + + assert(succ_block == NULL); + succ_block = get_edge_src_irn(edge); + if (get_Block_entity(succ_block) != NULL && entity != NULL) { + /* + * Currently we can add only one label for a block. + * Therefore we cannot combine them if both block already have one. + */ + goto check_preds; + } + + set_irn_n(succ_block, pos, pred); + } + + if (entity != NULL) { + /* move the label to the successor block */ + set_Block_entity(succ_block, entity); + } + + /* there can be some non-scheduled Pin nodes left in the block, move them + * to the succ block (Pin) or pred block (Sync) */ + foreach_out_edge_safe(block, edge) { + ir_node *const node = get_edge_src_irn(edge); + + if (node == jump) + continue; + /* we simply kill Pins, because there are some strange interactions + * between jump threading, which produce PhiMs with Pins, we simply + * kill the pins here, everything is scheduled anyway */ + if (is_Pin(node)) { + exchange(node, get_Pin_op(node)); + continue; + } + if (is_Sync(node)) { + set_nodes_block(node, get_nodes_block(pred)); + continue; + } + if (is_End(node)) { /* End-keep, reroute it to the successor */ + int pos = get_edge_src_pos(edge); + set_irn_n(node, pos, succ_block); + continue; + } + panic("Unexpected node %+F in block %+F with empty schedule", node, block); + } + + set_Block_cfgpred(block, 0, new_r_Bad(irg, mode_X)); + kill_node(jump); + blocks_removed = 1; + + /* check predecessor */ + remove_empty_block(get_nodes_block(pred)); + return; + +check_preds: + arity = get_Block_n_cfgpreds(block); + for (i = 0; i < arity; ++i) { + ir_node *pred = get_Block_cfgpred_block(block, i); + remove_empty_block(pred); + } } -pset *be_get_dominance_frontier(dom_front_info_t *info, ir_node *block) +/* removes basic blocks that just contain a jump instruction */ +int be_remove_empty_blocks(ir_graph *irg) { - return pmap_get(info->df_map, block); + ir_node *end; + int i, arity; + + blocks_removed = 0; + + ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED); + inc_irg_visited(irg); + remove_empty_block(get_irg_end_block(irg)); + end = get_irg_end(irg); + arity = get_irn_arity(end); + for (i = 0; i < arity; ++i) { + ir_node *pred = get_irn_n(end, i); + if (!is_Block(pred)) + continue; + remove_empty_block(pred); + } + ir_free_resources(irg, IR_RESOURCE_IRN_VISITED); + + if (blocks_removed) { + /* invalidate analysis info */ + clear_irg_properties(irg, IR_GRAPH_PROPERTY_CONSISTENT_DOMINANCE); + } + return blocks_removed; } +//--------------------------------------------------------------------------- + +typedef struct remove_dead_nodes_env_t_ { + bitset_t *reachable; + ir_graph *irg; + be_lv_t *lv; +} remove_dead_nodes_env_t; + /** - * Algorithm to place the Phi-Functions. - * @see Appel, Modern Compiler Implementation in Java, 2nd ed., p. 399ff - * - * This function takes an original node and a set of already placed - * copies of that node called @p copies. It places phi nodes at the - * iterated dominance frontiers of these copies and puts these phi nodes - * in the @p copies set, since they are another form of copies of the - * original value. - * - * The rename phase (see below) is responsible for fixing up the usages - * of the original node. - * - * @param orig The original node. - * @param copies A set contianing nodes representing a copy of the - * original node. Each node must be inserted into the block's schedule. - * @param copy_blocks A set in which the blocks are recorded which - * contain a copy. This is just for efficiency in later phases (see - * rename). + * Post-walker: remember all visited nodes in a bitset. */ -static void place_phi_functions(ir_node *orig, pset *copies, - pset *copy_blocks, dom_front_info_t *df_info) +static void mark_dead_nodes_walker(ir_node *node, void *data) { - int i; - ir_node *orig_block = get_nodes_block(orig); - ir_graph *irg = get_irn_irg(orig); - ir_mode *mode = get_irn_mode(orig); - pdeq *worklist = new_pdeq(); - pset *phi_blocks = pset_new_ptr(8); - ir_node **ins = NULL; - void *it; - firm_dbg_module_t *dbg = DBG_MODULE; - - /* - * Allocate an array for all blocks where the copies and the original - * value were defined. - */ - int n_orig_blocks = pset_count(copy_blocks); - ir_node **orig_blocks = malloc(n_orig_blocks * sizeof(orig_blocks[0])); - - /* - * Fill the worklist queue and the rest of the orig blocks array. - */ - for(it = pset_first(copies), i = 0; it; it = pset_next(copies)) { - ir_node *copy_block = get_nodes_block(it); - - if(!block_dominates(orig_block, copy_block)) { - assert(block_dominates(orig_block, copy_block) - && "The block of the copy must be dominated by the block of the value"); - } - - pdeq_putr(worklist, copy_block); - orig_blocks[i++] = copy_block; - } - - while(!pdeq_empty(worklist)) { - ir_node *bl = pdeq_getl(worklist); - ir_node *y; - pset *df = be_get_dominance_frontier(df_info, bl); - - DBG((dbg, LEVEL_3, "dom front of %+F\n", bl)); - for(y = pset_first(df); y; y = pset_next(df)) - DBG((dbg, LEVEL_3, "\t%+F\n", y)); - - for(y = pset_first(df); y; y = pset_next(df)) { - int n_preds = get_irn_arity(y); - - if(!pset_find_ptr(phi_blocks, y)) { - ir_node *phi; - int insert = 1; - - /* - * Set the orig node as the only operand of the - * phi node. - */ - ins = realloc(ins, n_preds * sizeof(ins[0])); - for(i = 0; i < n_preds; ++i) - ins[i] = orig; - - /* Insert phi node */ - phi = new_r_Phi(irg, y, n_preds, ins, mode); - DBG((dbg, LEVEL_2, " inserting phi %+F with %d args in block %+F\n", - phi, n_preds, y)); - - /* - * The phi node itself is also a copy of the original - * value. So put it in the copies set also, so that - * the rename phase can treat them right. - */ - pset_insert_ptr(copies, phi); - pset_insert_ptr(copy_blocks, y); - - /* - * Insert the phi node into the schedule if it - * can occur there (PhiM's are not to put into a schedule. - */ - if(to_appear_in_schedule(phi)) - sched_add_before(sched_first(y), phi); - - /* Insert the phi node in the phi blocks set. */ - pset_insert_ptr(phi_blocks, y); - - /* - * If orig or a copy of it were not defined in y, - * add y to the worklist. - */ - for(i = 0; i < n_orig_blocks; ++i) - if(orig_blocks[i] == y) { - insert = 0; - break; - } - - if(insert) - pdeq_putr(worklist, y); - - } - } - } - - del_pset(phi_blocks); - del_pdeq(worklist); - - free(orig_blocks); - - if(ins) - free(ins); + remove_dead_nodes_env_t *env = (remove_dead_nodes_env_t*) data; + bitset_set(env->reachable, get_irn_idx(node)); } /** - * Find the copy of the given original node whose value is 'active' - * at a usage. - * - * The usage is given as a node and a position. Initially, the given operand - * points to a node for which copies were introduced. We have to find - * the valid copy for this usage. This is done by travering the - * dominance tree upwards. If the usage is a phi function, we start - * traversing from the predecessor block which corresponds to the phi - * usage. - * - * @param usage The node which uses the original node. - * @param pos The number of the argument which corresponds to the - * original node. - * @param copy_blocks A set containing all basic block in which copies - * of the original node are located. - * @param copies A set containing all node which are copies from the - * original node. - * @return The valid copy for usage. + * Post-block-walker: + * Walk through the schedule of every block and remove all dead nodes from it. */ -static ir_node *search_def(ir_node *usage, int pos, pset *copies, pset *copy_blocks) +static void remove_dead_nodes_walker(ir_node *block, void *data) { - ir_node *curr_bl; - ir_node *start_irn; - firm_dbg_module_t *dbg = DBG_MODULE; - firm_dbg_set_mask(dbg, -1); - - curr_bl = get_nodes_block(usage); - - - DBG((dbg, LEVEL_1, "Searching valid def for use %+F at pos %d\n", usage, pos)); - /* - * If the usage is in a phi node, search the copy in the - * predecessor denoted by pos. - */ - if(is_Phi(usage)) { - curr_bl = get_Block_cfgpred_block(curr_bl, pos); - start_irn = sched_last(curr_bl); - } else { - start_irn = sched_prev(usage); - } - - /* - * Traverse the dominance tree upwards from the - * predecessor block of the usage. - */ - while(curr_bl != NULL) { - - /* - * If this block contains a copy, search the block - * instruction by instruction. - */ - if(pset_find_ptr(copy_blocks, curr_bl)) { - ir_node *irn; - - /* Look at each instruction from last to first. */ - for(irn = start_irn; !is_Block(irn); irn = sched_prev(irn)) { - - /* Take the first copy we find. */ - - DBG((dbg, LEVEL_1, "Is %F a copy?\n", irn)); - if(pset_find_ptr(copies, irn)) - return irn; - } - } - - /* If were not done yet, look in the immediate dominator */ - curr_bl = get_Block_idom(curr_bl); - if(curr_bl) - start_irn = sched_last(curr_bl); - } - - assert(0 && "Did not find a valid def"); - return NULL; + remove_dead_nodes_env_t *env = (remove_dead_nodes_env_t*) data; + ir_node *node, *next; + + for (node = sched_first(block); ! sched_is_end(node); node = next) { + /* get next node now, as after calling sched_remove it will be invalid */ + next = sched_next(node); + + if (bitset_is_set(env->reachable, get_irn_idx(node))) + continue; + + if (env->lv != NULL) + be_liveness_remove(env->lv, node); + sched_remove(node); + + /* kill projs */ + if (get_irn_mode(node) == mode_T) { + foreach_out_edge_safe(node, edge) { + ir_node *proj = get_edge_src_irn(edge); + if (!is_Proj(proj)) + continue; + if (env->lv != NULL) + be_liveness_remove(env->lv, proj); + kill_node(proj); + } + } + kill_node(node); + } } -static void fix_usages(ir_node *orig, pset *copies, pset *copy_blocks) +void be_remove_dead_nodes_from_schedule(ir_graph *irg) { - int i = 0; - int n_outs = 0; - const ir_edge_t *edge; - firm_dbg_module_t *dbg = DBG_MODULE; - - struct { - ir_node *irn; - int pos; - } *outs; - - /* Count the number of outs. */ - foreach_out_edge(orig, edge) - n_outs++; - - /* - * Put all outs into an array. - * This is neccessary, since the outs would be modified while - * interating on them what could bring the outs module in trouble. - */ - DBG((dbg, LEVEL_2, " Users of %+F\n", orig)); - outs = malloc(n_outs * sizeof(outs[0])); - foreach_out_edge(orig, edge) { - outs[i].irn = get_edge_src_irn(edge); - outs[i].pos = get_edge_src_pos(edge); - i += 1; - } - - /* - * Search the valid def for each out and set it. - */ - for(i = 0; i < n_outs; ++i) { - ir_node *def; - ir_node *irn = outs[i].irn; - int pos = outs[i].pos; - - DBG((dbg, LEVEL_2, " %+F(%d) -> ???\n", irn, pos)); - def = search_def(irn, pos, copies, copy_blocks); - DBG((dbg, LEVEL_2, " %+F(%d) -> %+F\n", irn, pos, def)); - - if(def != NULL) - set_irn_n(irn, pos, def); - } - - free(outs); -} + remove_dead_nodes_env_t env; + env.reachable = bitset_alloca(get_irg_last_idx(irg)); + env.lv = be_get_irg_liveness(irg); + env.irg = irg; -struct phi_collect_info { - const ir_node *orig; - pset *copies; - pset *copy_blocks; -}; - -static void add_all_phis_walker(ir_node *irn, void *data) -{ - if(is_Phi(irn)) { - int i, o, n; - struct phi_collect_info *info = data; - - /* - * Look at all operands of the phi. If one of them is the original - * node, insert the phi into the copies and copy_blocks set. - */ - for(i = 0, n = get_irn_arity(irn); i < n; ++i) { - if(get_irn_n(irn, i) == info->orig) { - pset_insert_ptr(info->copies, irn); - pset_insert_ptr(info->copy_blocks, get_nodes_block(irn)); - - break; - } - } - - - } -} - -/** - * Add all phis using a node to a set. - * @param orig The node the phis shall use. - * @param copies The set where the phis shall be put into. - * @param copy_blocks The set the blocks of the phis shall be put into. - */ -static void add_all_phis_using(const ir_node *orig, pset *copies, pset *copy_blocks) -{ - struct phi_collect_info info; + // mark all reachable nodes + irg_walk_graph(irg, mark_dead_nodes_walker, NULL, &env); - info.copies = copies; - info.copy_blocks = copy_blocks; - info.orig = orig; - irg_walk_graph(get_irn_irg(orig), add_all_phis_walker, NULL, &info); + // walk schedule and remove non-marked nodes + irg_block_walk_graph(irg, remove_dead_nodes_walker, NULL, &env); } -void be_introduce_copies(dom_front_info_t *info, ir_node *orig, int n, ir_node *copy_nodes[]) +BE_REGISTER_MODULE_CONSTRUCTOR(be_init_irgmod) +void be_init_irgmod(void) { - pset *copies = pset_new_ptr(2 * n); - pset *copy_blocks = pset_new_ptr(2 * n); - int save_optimize = get_optimize(); - int save_normalize = get_opt_normalize(); - firm_dbg_module_t *dbg = DBG_MODULE; - int i; - - firm_dbg_set_mask(dbg, -1); - DBG((dbg, LEVEL_1, "Introducing following copies of %+F\n", orig)); - - /* Fill the sets. */ - pset_insert_ptr(copies, orig); - pset_insert_ptr(copy_blocks, get_nodes_block(orig)); - - /* - * All phis using the original value are also copies of it - * and must be present in the copies set. - */ - /* add_all_phis_using(orig, copies, copy_blocks);*/ - - for(i = 0; i < n; ++i) { - DBG((dbg, LEVEL_1, - " %+F in block %+F\n", copy_nodes[i], get_nodes_block(copy_nodes[i]))); - pset_insert_ptr(copies, copy_nodes[i]); - pset_insert_ptr(copy_blocks, get_nodes_block(copy_nodes[i])); - } - - /* - * Disable optimization so that the phi functions do not - * disappear. - */ - set_optimize(0); - set_opt_normalize(0); - - /* - * Place the phi functions and reroute the usages. - */ - place_phi_functions(orig, copies, copy_blocks, info); - fix_usages(orig, copies, copy_blocks); - - /* reset the optimizations */ - set_optimize(save_optimize); - set_opt_normalize(save_normalize); - - del_pset(copies); - del_pset(copy_blocks); + FIRM_DBG_REGISTER(dbg, "firm.be.irgmod"); }