2 * Copyright (C) 1995-2011 University of Karlsruhe. All right reserved.
4 * This file is part of libFirm.
6 * This file may be distributed and/or modified under the terms of the
7 * GNU General Public License version 2 as published by the Free Software
8 * Foundation and appearing in the file LICENSE.GPL included in the
9 * packaging of this file.
11 * Licensees holding valid libFirm Professional Edition licenses may use
12 * this file in accordance with the libFirm Commercial License.
13 * Agreement provided with the Software.
15 * This file is provided AS IS with NO WARRANTY OF ANY KIND, INCLUDING THE
16 * WARRANTY OF DESIGN, MERCHANTABILITY AND FITNESS FOR A PARTICULAR
22 * @brief Blockwise walker implementation
23 * @author Michael Beck
28 #include "irgraph_t.h"
35 #define _get_walk_arity(env, node) \
36 ((env)->follow_deps ? get_irn_ins_or_deps((node)) : get_irn_arity((node)))
37 #define _get_walk_irn_n(env, node, pos) \
38 ((env)->follow_deps ? get_irn_in_or_dep((node), (pos)) : get_irn_n((node), (pos)))
41 * Metadata for block walker
43 typedef struct blk_collect_data_t {
44 struct obstack obst; /**< obstack to allocate objects on */
45 pset *blk_map; /**< Hash map: Block -> List */
46 ir_node **blk_list; /**< the Block list */
47 unsigned follow_deps : 1; /**< follow dependency edges */
51 * An entry for a block in the blk_map
53 typedef struct block_entry_t {
54 ir_node *block; /**< the block */
55 ir_node **phi_list; /**< the list of Phi instruction */
56 ir_node **df_list; /**< the list of data flow instruction */
57 ir_node **cf_list; /**< the list of control flow instructions */
58 ir_node **entry_list; /**< list of all block entries */
62 * compare two block_entries
64 static int addr_cmp(const void *elt, const void *key)
66 const block_entry_t *e1 = (const block_entry_t*)elt;
67 const block_entry_t *e2 = (const block_entry_t*)key;
69 return e1->block != e2->block;
73 * Returns the associates block_entry_t for an block
75 static block_entry_t *block_find_entry(ir_node *block, blk_collect_data_t *ctx)
81 elem = (block_entry_t*)pset_find(ctx->blk_map, &key, HASH_PTR(block));
85 elem = OALLOC(&ctx->obst, block_entry_t);
88 elem->phi_list = NEW_ARR_F(ir_node *, 0);
89 elem->df_list = NEW_ARR_F(ir_node *, 0);
90 elem->cf_list = NEW_ARR_F(ir_node *, 0);
91 elem->entry_list = NEW_ARR_F(ir_node *, 0);
93 return (block_entry_t*)pset_insert(ctx->blk_map, elem, HASH_PTR(block));
97 * Traverse a block in pre order.
99 static void traverse_block_pre(ir_node *block, block_entry_t *entry, irg_walk_func *pre, void *env)
103 for (j = ARR_LEN(entry->cf_list); j > 0;) {
104 ir_node *node = entry->cf_list[--j];
108 for (j = ARR_LEN(entry->df_list); j > 0;) {
109 ir_node *node = entry->df_list[--j];
113 for (j = ARR_LEN(entry->phi_list); j > 0;) {
114 ir_node *node = entry->phi_list[--j];
122 * Traverse a block in post order.
124 static void traverse_block_post(ir_node *block, block_entry_t *entry,
125 irg_walk_func *post, void *env)
131 for (j = 0, n = ARR_LEN(entry->phi_list); j < n; ++j) {
132 ir_node *node = entry->phi_list[j];
136 for (j = 0, n = ARR_LEN(entry->df_list); j < n; ++j) {
137 ir_node *node = entry->df_list[j];
141 for (j = 0, n = ARR_LEN(entry->cf_list); j < n; ++j) {
142 ir_node *node = entry->cf_list[j];
148 * traverse the pre order only, from End to Start
150 static void traverse_pre(blk_collect_data_t *blks, irg_walk_func *pre, void *env)
154 for (i = ARR_LEN(blks->blk_list); i > 0;) {
155 ir_node *block = blks->blk_list[--i];
156 block_entry_t *entry = block_find_entry(block, blks);
158 traverse_block_pre(block, entry, pre, env);
160 DEL_ARR_F(entry->entry_list);
161 DEL_ARR_F(entry->phi_list);
162 DEL_ARR_F(entry->df_list);
163 DEL_ARR_F(entry->cf_list);
168 * traverse the post order only, from Start to End
170 static void traverse_post(blk_collect_data_t *blks, irg_walk_func *post, void *env)
174 for (i = 0, k = ARR_LEN(blks->blk_list); i < k; ++i) {
175 ir_node *block = blks->blk_list[i];
176 block_entry_t *entry = block_find_entry(block, blks);
178 traverse_block_post(block, entry, post, env);
180 DEL_ARR_F(entry->entry_list);
181 DEL_ARR_F(entry->phi_list);
182 DEL_ARR_F(entry->df_list);
183 DEL_ARR_F(entry->cf_list);
190 static void traverse_both(blk_collect_data_t *blks, irg_walk_func *pre, irg_walk_func *post, void *env)
194 for (i = ARR_LEN(blks->blk_list); i > 0;) {
195 ir_node *block = blks->blk_list[--i];
196 block_entry_t *entry = block_find_entry(block, blks);
198 traverse_block_pre(block, entry, pre, env);
202 traverse_post(blks, post, env);
208 static void traverse_blocks(blk_collect_data_t *blks, irg_walk_func *pre, irg_walk_func *post, void *env)
210 if (!post) traverse_pre (blks, pre, env);
211 else if (!pre) traverse_post(blks, post, env);
212 else traverse_both(blks, pre, post, env);
215 typedef struct dom_traversal_t {
216 blk_collect_data_t *blks;
223 * Dom block walker. Visit all nodes in pre oder.
225 static void dom_block_visit_pre(ir_node *block, void *env)
227 dom_traversal_t *ctx = (dom_traversal_t*)env;
228 block_entry_t *entry = block_find_entry(block, ctx->blks);
230 traverse_block_pre(block, entry, ctx->pre, ctx->env);
234 * Dom block walker. Visit all nodes in post oder.
236 static void dom_block_visit_post(ir_node *block, void *env)
238 dom_traversal_t *ctx = (dom_traversal_t*)env;
239 block_entry_t *entry = block_find_entry(block, ctx->blks);
241 traverse_block_post(block, entry, ctx->post, ctx->env);
245 * Dom block walker. Visit all nodes in pre oder, than in post order.
247 static void dom_block_visit_both(ir_node *block, void *env)
249 dom_traversal_t *ctx = (dom_traversal_t*)env;
250 block_entry_t *entry = block_find_entry(block, ctx->blks);
252 traverse_block_pre(block, entry, ctx->pre, ctx->env);
253 traverse_block_post(block, entry, ctx->post, ctx->env);
257 * Do the traversal in the dominator tree in top-down order.
259 static void traverse_dom_blocks_top_down(blk_collect_data_t* blks, irg_walk_func *pre, irg_walk_func *post, void *env)
268 if (pre != NULL && post != NULL)
269 dom_tree_walk_irg(current_ir_graph, dom_block_visit_both, NULL, &ctx);
270 else if (pre != NULL)
271 dom_tree_walk_irg(current_ir_graph, dom_block_visit_pre, NULL, &ctx);
272 else if (post != NULL)
273 dom_tree_walk_irg(current_ir_graph, dom_block_visit_post, NULL, &ctx);
277 * walks over the graph and collects all blocks and all block entries
279 static void collect_walk(ir_node *node, blk_collect_data_t *env)
282 block_entry_t *entry;
285 mark_irn_visited(node);
287 if (is_Block(node)) {
288 /* predecessors of a block are control flow nodes */
289 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
290 ir_node *pred = _get_walk_irn_n(env, node, i);
291 ir_node *blk = get_nodes_block(pred);
293 if (!irn_visited(pred)) {
294 collect_walk(pred, env);
296 /* control flow predecessors are always block inputs */
297 entry = block_find_entry(blk, env);
298 ARR_APP1(ir_node *, entry->entry_list, pred);
302 /* it's a block, put it into the block list */
303 if (node == get_irg_end_block(current_ir_graph)) {
304 /* Put the end block always last. If we don't do it here,
305 * it might be placed elsewhere if the graph contains
309 ARR_APP1(ir_node *, env->blk_list, node);
313 block = get_nodes_block(node);
315 if (!irn_visited(block))
316 collect_walk(block, env);
318 is_phi = is_Phi(node);
319 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
320 ir_node *pred = _get_walk_irn_n(env, node, i);
322 if (!irn_visited(pred)) {
323 collect_walk(pred, env);
325 /* BEWARE: predecessors of End nodes might be blocks */
326 if (!is_Block(pred)) {
327 ir_node *blk = get_nodes_block(pred);
330 * Note that Phi predecessors are always block entries
331 * because Phi edges are always "outside" a block
333 if (block != blk || is_phi) {
334 entry = block_find_entry(blk, env);
335 ARR_APP1(ir_node *, entry->entry_list, pred);
344 * walks over the nodes of a block
345 * and collects them into the right list
347 static void collect_blks_lists(ir_node *node, ir_node *block,
348 block_entry_t *entry, blk_collect_data_t *env)
352 mark_irn_visited(node);
355 * Do not descent into Phi predecessors, these are always
356 * outside the current block because Phi edges are always
359 if (! is_Phi(node)) {
360 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
361 ir_node *pred = _get_walk_irn_n(env, node, i);
363 /* BEWARE: predecessors of End nodes might be blocks */
364 if (!is_Block(pred)) {
365 ir_node *blk = get_nodes_block(pred);
367 if (!irn_visited(pred)) {
370 collect_blks_lists(pred, block, entry, env);
375 ARR_APP1(ir_node *, entry->phi_list, node);
379 if (get_irn_mode(node) == mode_X) {
380 ARR_APP1(ir_node *, entry->cf_list, node);
382 ARR_APP1(ir_node *, entry->df_list, node);
387 * walk over the graph and collect all lists
389 static void collect_lists(blk_collect_data_t *env)
392 ir_node *block, *node;
393 block_entry_t *entry;
395 inc_irg_visited(current_ir_graph);
397 for (i = ARR_LEN(env->blk_list); i > 0;) {
398 block = env->blk_list[--i];
399 entry = block_find_entry(block, env);
401 for (j = ARR_LEN(entry->entry_list); j > 0;) {
402 node = entry->entry_list[--j];
404 /* a entry might already be visited due to Phi loops */
405 if (node->visited < current_ir_graph->visited)
406 collect_blks_lists(node, block, entry, env);
412 * Intra procedural graph walker over blocks.
414 static void do_irg_walk_blk(ir_graph *irg, irg_walk_func *pre,
415 irg_walk_func *post, void *env, unsigned follow_deps,
416 void (*traverse)(blk_collect_data_t* blks, irg_walk_func *pre, irg_walk_func *post, void *env))
418 ir_node *end_node = get_irg_end(irg);
419 ir_node *end_blk = get_irg_end_block(irg);
420 blk_collect_data_t blks;
421 block_entry_t *entry;
423 obstack_init(&blks.obst);
424 blks.blk_map = new_pset(addr_cmp, 1);
425 blks.blk_list = NEW_ARR_F(ir_node *, 0);
426 blks.follow_deps = follow_deps != 0;
428 /* first step: traverse the graph and fill the lists */
429 ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
430 inc_irg_visited(irg);
431 collect_walk(end_node, &blks);
433 /* add the end block */
434 ARR_APP1(ir_node *, blks.blk_list, end_blk);
436 /* and the end node */
437 entry = block_find_entry(end_blk, &blks);
438 ARR_APP1(ir_node *, entry->entry_list, end_node);
440 collect_lists(&blks);
442 /* second step: traverse the list */
443 traverse(&blks, pre, post, env);
445 DEL_ARR_F(blks.blk_list);
446 del_pset(blks.blk_map);
447 obstack_free(&blks.obst, NULL);
449 ir_free_resources(irg, IR_RESOURCE_IRN_VISITED);
452 void irg_walk_blkwise_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env)
454 ir_graph * rem = current_ir_graph;
456 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
457 current_ir_graph = irg;
458 do_irg_walk_blk(irg, pre, post, env, 0, traverse_blocks);
459 current_ir_graph = rem;
462 void irg_walk_in_or_dep_blkwise_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env)
464 ir_graph * rem = current_ir_graph;
466 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
467 current_ir_graph = irg;
468 do_irg_walk_blk(irg, pre, post, env, 1, traverse_blocks);
469 current_ir_graph = rem;
472 void irg_walk_blkwise_dom_top_down(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env)
474 ir_graph * rem = current_ir_graph;
476 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
477 current_ir_graph = irg;
478 do_irg_walk_blk(irg, pre, post, env, 0, traverse_dom_blocks_top_down);
479 current_ir_graph = rem;