X-Git-Url: http://nsz.repo.hu/git/?a=blobdiff_plain;f=ir%2Fana%2Firdom.c;h=852889d885af0f9a94716af232ae6227fae39d94;hb=0ed495da32589b78283d9ede3cb9e33727316006;hp=ff524abc00831972a085605baac5edf80a3a1e43;hpb=67e3ef5e7088c2254daeb2a72e0950bef6ca0256;p=libfirm diff --git a/ir/ana/irdom.c b/ir/ana/irdom.c index ff524abc0..852889d88 100644 --- a/ir/ana/irdom.c +++ b/ir/ana/irdom.c @@ -1,276 +1,816 @@ -/* Copyright (C) 2002 by Universitaet Karlsruhe -** All rights reserved. -** -** Authors: Goetz Lindenmaier -** -** irdom.c --- Dominator tree. -** -*/ - -/* $Id$ */ +/* + * 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 Construct and access dominator / post dominator tree. + * @author Goetz Lindenmaier, Michael Beck, Rubino Geiss + * @date 2.2002 + */ +#include "config.h" + +#include #include "irouts.h" +#include "xmalloc.h" #include "irgwalk.h" #include "irdom_t.h" -#include "irgraph_t.h" /* To access state field. */ +#include "irgraph_t.h" #include "irnode_t.h" +#include "ircons_t.h" +#include "array_t.h" +#include "iredges.h" + + +#define get_dom_info(bl) (&(bl)->attr.block.dom) +#define get_pdom_info(bl) (&(bl)->attr.block.pdom) + +ir_node *get_Block_idom(const ir_node *bl) +{ + assert(is_Block(bl)); + if (get_Block_dom_depth(bl) == -1) { + /* This block is not reachable from Start */ + ir_graph *irg = get_irn_irg(bl); + return new_r_Bad(irg, mode_BB); + } + return get_dom_info(bl)->idom; +} + +void set_Block_idom(ir_node *bl, ir_node *n) +{ + ir_dom_info *bli = get_dom_info(bl); + + assert(is_Block(bl)); + + /* Set the immediate dominator of bl to n */ + bli->idom = n; + + /* + * If we don't set the root of the dominator tree + * Append bl to the dominates queue of n. + */ + if (n != NULL) { + ir_dom_info *ni = get_dom_info(n); + + bli->next = ni->first; + ni->first = bl; + } +} + +ir_node *get_Block_ipostdom(const ir_node *bl) +{ + assert(is_Block(bl)); + if (get_Block_postdom_depth(bl) == -1) { + /* This block is not reachable from Start */ + ir_graph *irg = get_irn_irg(bl); + return new_r_Bad(irg, mode_BB); + } + return get_pdom_info(bl)->idom; +} + +void set_Block_ipostdom(ir_node *bl, ir_node *n) +{ + ir_dom_info *bli = get_pdom_info(bl); + + assert(is_Block(bl)); + + /* Set the immediate post dominator of bl to n */ + bli->idom = n; + + /* + * If we don't set the root of the post dominator tree + * Append bl to the post dominates queue of n. + */ + if (n != NULL) { + ir_dom_info *ni = get_pdom_info(n); + + bli->next = ni->first; + ni->first = bl; + } +} + +int get_Block_dom_pre_num(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_dom_info(bl)->pre_num; +} + +void set_Block_dom_pre_num(ir_node *bl, int num) +{ + assert(is_Block(bl)); + get_dom_info(bl)->pre_num = num; +} + +int get_Block_dom_depth(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_dom_info(bl)->dom_depth; +} + +void set_Block_dom_depth(ir_node *bl, int depth) +{ + assert(is_Block(bl)); + get_dom_info(bl)->dom_depth = depth; +} -/**********************************************************************/ -/** Accessing the dominator datastructures **/ -/**********************************************************************/ -ir_node *get_Block_idom(ir_node *bl) { - assert(get_irn_op(bl) == op_Block); - return bl->attr.block.dom.idom; +int get_Block_postdom_pre_num(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_pdom_info(bl)->pre_num; } -void set_Block_idom(ir_node *bl, ir_node *n) { - assert(get_irn_op(bl) == op_Block); - bl->attr.block.dom.idom = n; +void set_Block_postdom_pre_num(ir_node *bl, int num) +{ + assert(is_Block(bl)); + get_pdom_info(bl)->pre_num = num; +} + +int get_Block_postdom_depth(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_pdom_info(bl)->dom_depth; } -int get_Block_pre_num(ir_node *bl) { - assert(get_irn_op(bl) == op_Block); - return bl->attr.block.dom.pre_num; +void set_Block_postdom_depth(ir_node *bl, int depth) +{ + assert(is_Block(bl)); + get_pdom_info(bl)->dom_depth = depth; +} + +unsigned get_Block_dom_tree_pre_num(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_dom_info(bl)->tree_pre_num; } -void set_Block_pre_num(ir_node *bl, int num) { - assert(get_irn_op(bl) == op_Block); - bl->attr.block.dom.pre_num = num; +unsigned get_Block_dom_max_subtree_pre_num(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_dom_info(bl)->max_subtree_pre_num; } -int get_Block_dom_depth(ir_node *bl) { - assert(get_irn_op(bl) == op_Block); - return bl->attr.block.dom.dom_depth; +unsigned get_Block_pdom_tree_pre_num(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_pdom_info(bl)->tree_pre_num; } -void set_Block_dom_depth(ir_node *bl, int depth) { - assert(get_irn_op(bl) == op_Block); - bl->attr.block.dom.dom_depth = depth; +unsigned get_Block_pdom_max_subtree_pre_num(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_pdom_info(bl)->max_subtree_pre_num; } +int block_dominates(const ir_node *a, const ir_node *b) +{ + const ir_dom_info *ai, *bi; + if (is_Block(a) && is_Block(b)) { + ai = get_dom_info(a); + bi = get_dom_info(b); + return bi->tree_pre_num - ai->tree_pre_num + <= ai->max_subtree_pre_num - ai->tree_pre_num; + } -/**********************************************************************/ -/** Building and Removing the dominator datasturcture **/ -/** **/ -/** **/ -/** **/ -/** **/ -/** **/ -/** **/ -/** **/ -/** .**/ -/** **/ -/** **/ -/** **/ -/** **/ -/** **/ -/** **/ -/**********************************************************************/ + return 0; +} -void count_and_init_blocks(ir_node *bl, void *env) { - int *n_blocks = (int *) env; - (*n_blocks) ++; +int block_strictly_dominates(const ir_node *a, const ir_node *b) +{ + return (a != b) && block_dominates(a, b); +} - set_Block_idom(bl, NULL); - set_Block_pre_num(bl, -1); - set_Block_dom_depth(bl, -1); +ir_node *node_smallest_common_dominator(ir_node *a, ir_node *b) +{ + ir_node *bl_a = is_Block(a) ? a : get_nodes_block(a); + ir_node *bl_b = is_Block(b) ? b : get_nodes_block(b); + ir_node *dom_bl = NULL; + + /* Check if block of a dominates block of b */ + if (block_dominates(bl_a, bl_b)) + dom_bl = bl_a; + /* Check if block of b dominates block of a */ + else if (block_dominates(bl_b, bl_a)) + dom_bl = bl_b; + else { + /* walk up dominator tree and search for first block dominating a and b */ + while (! dom_bl) { + bl_a = get_Block_idom(bl_a); + + assert(! is_Bad(bl_a) && "block is dead?"); + + if (block_dominates(bl_a, bl_b)) + dom_bl = bl_a; + } + } + + return dom_bl; } -/* temporary type used while constructing the dominator tree. */ +/* Get the first node in the list of nodes dominated by a given block. */ +ir_node *get_Block_dominated_first(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_dom_info(bl)->first; +} + +ir_node *get_Block_dominated_next(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_dom_info(bl)->next; +} + +int block_postdominates(const ir_node *a, const ir_node *b) +{ + const ir_dom_info *ai, *bi; + + if (is_Block(a) && is_Block(b)) { + ai = get_pdom_info(a); + bi = get_pdom_info(b); + return bi->tree_pre_num - ai->tree_pre_num + <= ai->max_subtree_pre_num - ai->tree_pre_num; + } + + return 0; +} + +int block_strictly_postdominates(const ir_node *a, const ir_node *b) +{ + return (a != b) && block_postdominates(a, b); +} + +ir_node *get_Block_postdominated_first(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_pdom_info(bl)->first; +} + +ir_node *get_Block_postdominated_next(const ir_node *bl) +{ + assert(is_Block(bl)); + return get_pdom_info(bl)->next; +} + +void dom_tree_walk(ir_node *bl, irg_walk_func *pre, + irg_walk_func *post, void *env) +{ + ir_node *p; + + if (pre) + pre(bl, env); + + dominates_for_each(bl, p) { + dom_tree_walk(p, pre, post, env); + } + + if (post) + post(bl, env); +} + +void postdom_tree_walk(ir_node *bl, irg_walk_func *pre, + irg_walk_func *post, void *env) +{ + ir_node *p; + + if (pre) + pre(bl, env); + + postdominates_for_each(bl, p) { + postdom_tree_walk(p, pre, post, env); + } + + if (post) + post(bl, env); +} + +void dom_tree_walk_irg(ir_graph *irg, irg_walk_func *pre, + irg_walk_func *post, void *env) +{ + /* The root of the dominator tree should be the Start block. */ + ir_node *root = get_irg_start_block(irg); + + assert(is_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_DOMINANCE) + && "The dominators of the irg must be consistent"); + assert(root && "The start block of the graph is NULL?"); + assert(get_dom_info(root)->idom == NULL + && "The start node in the graph must be the root of the dominator tree"); + dom_tree_walk(root, pre, post, env); +} + +void postdom_tree_walk_irg(ir_graph *irg, irg_walk_func *pre, + irg_walk_func *post, void *env) +{ + /* The root of the post dominator tree should be the End block. */ + ir_node *root = get_irg_end_block(irg); + + assert(is_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_POSTDOMINANCE) + && "The dominators of the irg must be consistent"); + assert(root && "The end block of the graph is NULL?"); + assert(get_pdom_info(root)->idom == NULL + && "The End block node in the graph must be the root of the post dominator tree"); + postdom_tree_walk(root, pre, post, env); +} + + +static void assign_tree_dom_pre_order(ir_node *bl, void *data) +{ + unsigned *num = (unsigned*) data; + ir_dom_info *bi = get_dom_info(bl); + + bi->tree_pre_num = (*num)++; +} + +static void assign_tree_dom_pre_order_max(ir_node *bl, void *data) +{ + ir_dom_info *bi = get_dom_info(bl); + ir_node *p; + unsigned max = 0; + unsigned children = 0; + (void) data; + + for (p = bi->first; p; p = get_dom_info(p)->next) { + unsigned max_p = get_dom_info(p)->max_subtree_pre_num; + max = max > max_p ? max : max_p; + children++; + } + + bi->max_subtree_pre_num = children > 0 ? max : bi->tree_pre_num; + assert(bi->max_subtree_pre_num >= bi->tree_pre_num); +} + +static void assign_tree_postdom_pre_order(ir_node *bl, void *data) +{ + unsigned *num = (unsigned*) data; + ir_dom_info *bi = get_pdom_info(bl); + + bi->tree_pre_num = (*num)++; +} + +static void assign_tree_postdom_pre_order_max(ir_node *bl, void *data) +{ + ir_dom_info *bi = get_pdom_info(bl); + ir_node *p; + unsigned max = 0; + unsigned children = 0; + (void) data; + + for (p = bi->first; p; p = get_pdom_info(p)->next) { + unsigned max_p = get_pdom_info(p)->max_subtree_pre_num; + max = max > max_p ? max : max_p; + children++; + } + + bi->max_subtree_pre_num = children > 0 ? max : bi->tree_pre_num; + assert(bi->max_subtree_pre_num >= bi->tree_pre_num); +} + +/** + * count the number of blocks and clears the post dominance info + */ +static void count_and_init_blocks_pdom(ir_node *bl, void *env) +{ + int *n_blocks = (int *) env; + + (*n_blocks) ++; + + memset(get_pdom_info(bl), 0, sizeof(ir_dom_info)); + set_Block_ipostdom(bl, NULL); + set_Block_postdom_pre_num(bl, -1); + set_Block_postdom_depth(bl, -1); +} + +/** temporary type used while constructing the dominator / post dominator tree. */ typedef struct tmp_dom_info { - ir_node *block; /* backlink */ - - struct tmp_dom_info *semi; /* semidominator */ - struct tmp_dom_info *parent; - struct tmp_dom_info *label; /* used for LINK and EVAL */ - struct tmp_dom_info *ancestor;/* used for LINK and EVAL */ - struct tmp_dom_info *dom; /* After step 3, if the semidominator of w is - its immediate dominator, then w->dom is the - immediate dominator of w. Otherwise w->dom - is a vertex v whose number is smaller than - w and whose immediate dominator is also w's - immediate dominator. After step 4, w->dom - is the immediate dominator of w. */ - struct tmp_dom_info *bucket; /* set of vertices with same semidominator */ + ir_node *block; /**< backlink */ + + struct tmp_dom_info *semi; /**< semidominator */ + struct tmp_dom_info *parent; + struct tmp_dom_info *label; /**< used for LINK and EVAL */ + struct tmp_dom_info *ancestor;/**< used for LINK and EVAL */ + struct tmp_dom_info *dom; /**< After step 3, if the semidominator of w is + its immediate dominator, then w->dom is the + immediate dominator of w. Otherwise w->dom + is a vertex v whose number is smaller than + w and whose immediate dominator is also w's + immediate dominator. After step 4, w->dom + is the immediate dominator of w. */ + struct tmp_dom_info *bucket; /**< set of vertices with same semidominator */ } tmp_dom_info; -/* Struct to pass info through walker. */ +/** Struct to pass info through walker. */ typedef struct { - tmp_dom_info *d; - int used; - + tmp_dom_info *d; + int used; } dom_env; -/* Walks Blocks along the out datastructure. If recursion started with - Start block misses control dead blocks. */ -void init_tmp_dom_info(ir_node *bl, tmp_dom_info *parent, - tmp_dom_info *tdi_list, int* used) { - tmp_dom_info *tdi; - int i; +/** + * Walks Blocks along the out data structure. If recursion started with + * Start block misses control dead blocks. + */ +static void init_tmp_dom_info(ir_node *bl, tmp_dom_info *parent, + tmp_dom_info *tdi_list, int *used, int n_blocks) +{ + tmp_dom_info *tdi; + int i; + + assert(is_Block(bl)); + if (Block_block_visited(bl)) + return; + mark_Block_block_visited(bl); + set_Block_dom_pre_num(bl, *used); + + assert(*used < n_blocks); + tdi = &tdi_list[*used]; + ++(*used); + + tdi->semi = tdi; + tdi->label = tdi; + tdi->ancestor = NULL; + tdi->bucket = NULL; + tdi->parent = parent; + tdi->block = bl; + + /* Iterate */ + for (i = get_Block_n_cfg_outs_ka(bl) - 1; i >= 0; --i) { + ir_node *pred = get_Block_cfg_out_ka(bl, i); + /* can happen for half-optimized dead code (I've seen this in student + projects */ + if (!is_Block(pred)) + continue; + + init_tmp_dom_info(pred, tdi, tdi_list, used, n_blocks); + } +} + +/** + * Walks Blocks along the control flow. If recursion started with + * End block misses blocks in endless loops. + */ +static void init_tmp_pdom_info(ir_node *bl, tmp_dom_info *parent, + tmp_dom_info *tdi_list, int* used, int n_blocks) +{ + tmp_dom_info *tdi; + int i; + + assert(is_Block(bl)); + if (get_irg_block_visited(current_ir_graph) == get_Block_block_visited(bl)) + return; + mark_Block_block_visited(bl); + set_Block_postdom_pre_num(bl, *used); + + assert(*used < n_blocks); + tdi = &tdi_list[*used]; + ++(*used); + + tdi->semi = tdi; + tdi->label = tdi; + tdi->ancestor = NULL; + tdi->bucket = NULL; + tdi->parent = parent; + tdi->block = bl; + + /* Iterate */ + for (i = get_Block_n_cfgpreds(bl) - 1; i >= 0; --i) { + ir_node *pred = get_Block_cfgpred_block(bl, i); + if (is_Bad(pred)) + continue; + assert(is_Block(pred)); + init_tmp_pdom_info(pred, tdi, tdi_list, used, n_blocks); + } + + /* Handle keep-alives. Note that the preprocessing + in init_construction() had already killed all + phantom keep-alive edges. All remaining block keep-alives + are really edges to endless loops. + */ + if (bl == get_irg_end_block(current_ir_graph)) { + ir_node *end = get_irg_end(current_ir_graph); + + for (i = get_irn_arity(end) - 1; i >= 0; --i) { + ir_node *pred = get_irn_n(end, i); + + if (is_Block(pred)) + init_tmp_pdom_info(pred, tdi, tdi_list, used, n_blocks); + } + } +} + +static void dom_compress(tmp_dom_info *v) +{ + assert (v->ancestor); + if (v->ancestor->ancestor) { + dom_compress (v->ancestor); + if (v->ancestor->label->semi < v->label->semi) { + v->label = v->ancestor->label; + } + v->ancestor = v->ancestor->ancestor; + } +} + +/** + * if V is a root, return v, else return the vertex u, not being the + * root, with minimum u->semi on the path from v to its root. + */ +inline static tmp_dom_info *dom_eval(tmp_dom_info *v) +{ + if (!v->ancestor) return v; + dom_compress (v); + return v->label; +} + +/** make V W's ancestor */ +inline static void dom_link(tmp_dom_info *v, tmp_dom_info *w) +{ + w->ancestor = v; +} + +/** + * Walker: count the number of blocks and clears the dominance info + */ +static void count_and_init_blocks_dom(ir_node *bl, void *env) +{ + int *n_blocks = (int *) env; - assert(get_irn_op(bl) == op_Block); - if (get_irg_block_visited(current_ir_graph) == get_Block_block_visited(bl)) - return; - mark_Block_block_visited(bl); - set_Block_pre_num(bl, *used); + (*n_blocks) ++; - //printf(" used: %d ", *used); DDMN(bl); + memset(get_dom_info(bl), 0, sizeof(ir_dom_info)); + set_Block_idom(bl, NULL); + set_Block_dom_pre_num(bl, -1); + set_Block_dom_depth(bl, -1); +} - tdi = &tdi_list[*used]; - ++(*used); +void compute_doms(ir_graph *irg) +{ + ir_graph *rem = current_ir_graph; + int n_blocks, used, i, j; + tmp_dom_info *tdi_list; /* Ein Golf? */ + + current_ir_graph = irg; + + /* Update graph state */ + assert(get_irg_phase_state(irg) != phase_building); + + /* Count the number of blocks in the graph. */ + n_blocks = 0; + irg_block_walk_graph(irg, count_and_init_blocks_dom, NULL, &n_blocks); + + /* Memory for temporary information. */ + tdi_list = XMALLOCNZ(tmp_dom_info, n_blocks); + + /* We need the out data structure. */ + assure_irg_outs(irg); + + /* this with a standard walker as passing the parent to the sons isn't + simple. */ + used = 0; + inc_irg_block_visited(irg); + init_tmp_dom_info(get_irg_start_block(irg), NULL, tdi_list, &used, n_blocks); + /* If not all blocks are reachable from Start by out edges this assertion + fails. + assert(used == n_blocks && "Precondition for dom construction violated"); */ + assert(used <= n_blocks && "Precondition for dom construction violated"); + n_blocks = used; + + + for (i = n_blocks-1; i > 0; i--) { /* Don't iterate the root, it's done. */ + tmp_dom_info *w = &tdi_list[i]; + ir_node *block = w->block; + tmp_dom_info *v; + int irn_arity; + + /* Step 2 */ + irn_arity = get_irn_arity(block); + for (j = 0; j < irn_arity; j++) { + ir_node *pred = get_Block_cfgpred(block, j); + ir_node *pred_block = get_nodes_block(pred); + tmp_dom_info *u; + + if (is_Bad(pred) || (get_Block_dom_pre_num (pred_block) == -1)) + continue; /* unreachable */ + + u = dom_eval (&tdi_list[get_Block_dom_pre_num(pred_block)]); + if (u->semi < w->semi) + w->semi = u->semi; + } + + /* handle keep-alives if we are at the end block */ + if (block == get_irg_end_block(irg)) { + ir_node *end = get_irg_end(irg); + + irn_arity = get_irn_arity(end); + for (j = 0; j < irn_arity; j++) { + ir_node *pred = get_irn_n(end, j); + tmp_dom_info *u; + + if (!is_Block(pred) || get_Block_dom_pre_num(pred) == -1) + continue; /* unreachable */ + + u = dom_eval (&tdi_list[get_Block_dom_pre_num(pred)]); + if (u->semi < w->semi) + w->semi = u->semi; + } + } + + /* Add w to w->semi's bucket. w is in exactly one bucket, so + buckets can been implemented as linked lists. */ + w->bucket = w->semi->bucket; + w->semi->bucket = w; + + dom_link (w->parent, w); + + /* Step 3 */ + while (w->parent->bucket) { + tmp_dom_info *u; + v = w->parent->bucket; + /* remove v from w->parent->bucket */ + w->parent->bucket = v->bucket; + v->bucket = NULL; + + u = dom_eval (v); + if (u->semi < v->semi) + v->dom = u; + else + v->dom = w->parent; + } + } + /* Step 4 */ + tdi_list[0].dom = NULL; + set_Block_idom(tdi_list[0].block, NULL); + set_Block_dom_depth(tdi_list[0].block, 1); + for (i = 1; i < n_blocks; i++) { + tmp_dom_info *w = &tdi_list[i]; + int depth; + + if (! w->dom) + continue; /* control dead */ + + if (w->dom != w->semi) + w->dom = w->dom->dom; + set_Block_idom(w->block, w->dom->block); + + /* blocks dominated by dead one's are still dead */ + depth = get_Block_dom_depth(w->dom->block); + if (depth > 0) + ++depth; + set_Block_dom_depth(w->block, depth); + } + + /* clean up */ + free(tdi_list); + + /* Do a walk over the tree and assign the tree pre orders. */ + { + unsigned tree_pre_order = 0; + dom_tree_walk(get_irg_start_block(irg), assign_tree_dom_pre_order, + assign_tree_dom_pre_order_max, &tree_pre_order); + } + current_ir_graph = rem; + set_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_DOMINANCE); +} - tdi->semi = tdi; - tdi->label = tdi; - tdi->ancestor = NULL; - tdi->bucket = NULL; - tdi->parent = parent; - tdi->block = bl; +void assure_doms(ir_graph *irg) +{ + if (! is_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_DOMINANCE)) + compute_doms(irg); +} + +void free_dom(ir_graph *irg) +{ + /* Update graph state */ + assert(get_irg_phase_state(irg) != phase_building); + clear_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_DOMINANCE); - /* Iterate */ - for(i = 0; i < get_Block_n_cfg_outs(bl); i++) { - ir_node *pred = get_Block_cfg_out(bl, i); - assert(get_irn_opcode(pred) == iro_Block); - init_tmp_dom_info(pred, tdi, tdi_list, used); - } + /* With the implementation right now there is nothing to free, + but better call it anyways... */ } +void compute_postdoms(ir_graph *irg) +{ + ir_graph *rem = current_ir_graph; + int n_blocks, used, i, j; + tmp_dom_info *tdi_list; + + current_ir_graph = irg; + + /* Update graph state */ + assert(get_irg_phase_state(irg) != phase_building); + + /* Count the number of blocks in the graph. */ + n_blocks = 0; + irg_block_walk_graph(irg, count_and_init_blocks_pdom, NULL, &n_blocks); + + /* Memory for temporary information. */ + tdi_list = XMALLOCNZ(tmp_dom_info, n_blocks); + + /* We need the out data structure. */ + assure_irg_outs(irg); + + /* this with a standard walker as passing the parent to the sons isn't + simple. */ + used = 0; + inc_irg_block_visited(irg); + init_tmp_pdom_info(get_irg_end_block(irg), NULL, tdi_list, &used, n_blocks); + /* If not all blocks are reachable from End by cfg edges this assertion + fails. + assert(used == n_blocks && "Precondition for dom construction violated"); */ + n_blocks = used; + + + for (i = n_blocks-1; i > 0; i--) { /* Don't iterate the root, it's done. */ + int irn_arity; + tmp_dom_info *w = &tdi_list[i]; + tmp_dom_info *v; + + /* Step 2 */ + irn_arity = get_Block_n_cfg_outs_ka(w->block); + for (j = 0; j < irn_arity; j++) { + ir_node *succ = get_Block_cfg_out_ka(w->block, j); + tmp_dom_info *u; + + if (get_Block_postdom_pre_num (succ) == -1) + continue; /* endless-loop */ + + u = dom_eval (&tdi_list[get_Block_postdom_pre_num(succ)]); + if (u->semi < w->semi) w->semi = u->semi; + } + /* Add w to w->semi's bucket. w is in exactly one bucket, so + buckets can be implemented as linked lists. */ + w->bucket = w->semi->bucket; + w->semi->bucket = w; + + dom_link (w->parent, w); + + /* Step 3 */ + while (w->parent->bucket) { + tmp_dom_info *u; + v = w->parent->bucket; + /* remove v from w->parent->bucket */ + w->parent->bucket = v->bucket; + v->bucket = NULL; + + u = dom_eval(v); + if (u->semi < v->semi) + v->dom = u; + else + v->dom = w->parent; + } + } + /* Step 4 */ + tdi_list[0].dom = NULL; + set_Block_ipostdom(tdi_list[0].block, NULL); + set_Block_postdom_depth(tdi_list[0].block, 1); + for (i = 1; i < n_blocks; i++) { + tmp_dom_info *w = &tdi_list[i]; + + if (w->dom != w->semi) w->dom = w->dom->dom; + set_Block_ipostdom(w->block, w->dom->block); + set_Block_postdom_depth(w->block, get_Block_postdom_depth(w->dom->block) + 1); + } + + /* clean up */ + free(tdi_list); + + /* Do a walk over the tree and assign the tree pre orders. */ + { + unsigned tree_pre_order = 0; + postdom_tree_walk(get_irg_end_block(irg), assign_tree_postdom_pre_order, + assign_tree_postdom_pre_order_max, &tree_pre_order); + } + current_ir_graph = rem; + set_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_POSTDOMINANCE); +} -static void -dom_compress (tmp_dom_info *v) +void assure_postdoms(ir_graph *irg) { - assert (v->ancestor); - if (v->ancestor->ancestor) { - dom_compress (v->ancestor); - if (v->ancestor->label->semi < v->label->semi) { - v->label = v->ancestor->label; - } - v->ancestor = v->ancestor->ancestor; - } -} - -/* if V is a root, return v, else return the vertex u, not being the - root, with minimum u->semi on the path from v to its root. */ -inline static tmp_dom_info* -dom_eval (tmp_dom_info *v) -{ - if (!v->ancestor) return v; - dom_compress (v); - return v->label; -} - -/* make V W's ancestor */ -inline static void -dom_link (tmp_dom_info *v, tmp_dom_info *w) + if (! is_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_POSTDOMINANCE)) + compute_postdoms(irg); +} + +void free_postdom(ir_graph *irg) { - w->ancestor = v; -} - -/* Computes the dominator trees. Sets a flag in irg to "dom_consistent". - If the control flow of the graph is changed this flag must be set to - "dom_inconsistent". */ -void compute_doms(ir_graph *irg) { - ir_graph *rem = current_ir_graph; - int n_blocks, used, i, j; - tmp_dom_info *tdi_list; /* Ein Golf? */ - - current_ir_graph = irg; - - /* Update graph state */ - assert(get_irg_phase_state(current_ir_graph) != phase_building); - current_ir_graph->dom_state = dom_consistent; - - /* Count the number of blocks in the graph. */ - n_blocks = 0; - irg_block_walk(get_irg_end(current_ir_graph), count_and_init_blocks, NULL, &n_blocks); - - //printf("n_blocks is %d\n", n_blocks); - - /* Memory for temporary information. */ - tdi_list = (tmp_dom_info *) calloc(n_blocks, sizeof(tmp_dom_info)); - - /* We need the out datastructure. */ - if (current_ir_graph->outs_state != outs_consistent) - compute_outs(current_ir_graph); - - /** Initialize the temporary information, add link to parent. We don't do - this with a standard walker as passing the parent to the sons isn't - simple. **/ - used = 0; - inc_irg_block_visited(current_ir_graph); - init_tmp_dom_info(get_irg_start_block(current_ir_graph), NULL, tdi_list, &used); - /* If not all blocks are reachable from Start by out edges this assertion - fails. */ - //assert(used == n_blocks && "Precondition for dom construction violated"); - n_blocks = used; - - //printf("used is %d\n", used); - - - for (i = n_blocks-1; i > 0; i--) { /* Don't iterate the root, it's done. */ - tmp_dom_info *w = &tdi_list[i]; - tmp_dom_info *v; - - //printf(" cfgpreds: %d ", get_Block_n_cfgpreds(w->block)); DDMN(w->block); - - /* Step 2 */ - for (j = 0; j < get_irn_arity(w->block); j++) { - ir_node *pred = get_nodes_Block(get_Block_cfgpred(w->block, j)); - tmp_dom_info *u; - - if ((is_Bad(get_Block_cfgpred(w->block, j))) || (get_Block_pre_num (pred) == -1)) - continue; /* control-dead */ - - u = dom_eval (&tdi_list[get_Block_pre_num(pred)]); - if (u->semi < w->semi) w->semi = u->semi; - } - /* Add w to w->semi's bucket. w is in exactly one bucket, so - buckets can ben implemented as linked lists. */ - w->bucket = w->semi->bucket; - w->semi->bucket = w; - - dom_link (w->parent, w); - - /* Step 3 */ - while (w->parent->bucket) { - tmp_dom_info *u; - v = w->parent->bucket; - /* remove v from w->parent->bucket */ - w->parent->bucket = v->bucket; - v->bucket = NULL; - - u = dom_eval (v); - if (u->semi < v->semi) - v->dom = u; - else - v->dom = w->parent; - } - } - /* Step 4 */ - tdi_list[0].dom = NULL; - set_Block_idom(tdi_list[0].block, NULL); - set_Block_dom_depth(tdi_list[0].block, 1); - for (i = 1; i < n_blocks; i++) { - tmp_dom_info *w = &tdi_list[i]; - - if (w->dom != w->semi) w->dom = w->dom->dom; - set_Block_idom(w->block, w->dom->block); - set_Block_dom_depth(w->block, get_Block_dom_depth(w->dom->block) + 1); - } - - /* clean up */ - // free(tdi_list); - current_ir_graph = rem; -} - -void free_dom_and_peace(ir_graph *irg) { - /* Update graph state */ - assert(get_irg_phase_state(current_ir_graph) != phase_building); - current_ir_graph->dom_state = no_dom; - - /* With the implementation right now there is nothing to free, - but better call it anyways... */ + /* Update graph state */ + assert(get_irg_phase_state(irg) != phase_building); + clear_irg_state(irg, IR_GRAPH_STATE_CONSISTENT_POSTDOMINANCE); + + /* With the implementation right now there is nothing to free, + but better call it anyways... */ }