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
29 #include "irgraph_t.h"
36 #define _get_walk_arity(env, node) \
37 ((env)->follow_deps ? get_irn_ins_or_deps((node)) : get_irn_arity((node)))
38 #define _get_walk_irn_n(env, node, pos) \
39 ((env)->follow_deps ? get_irn_in_or_dep((node), (pos)) : get_irn_n((node), (pos)))
42 * Metadata for block walker
44 typedef struct blk_collect_data_t {
45 struct obstack obst; /**< obstack to allocate objects on */
46 pset *blk_map; /**< Hash map: Block -> List */
47 ir_node **blk_list; /**< the Block list */
48 unsigned follow_deps : 1; /**< follow dependency edges */
52 * An entry for a block in the blk_map
54 typedef struct block_entry_t {
55 ir_node *block; /**< the block */
56 ir_node **phi_list; /**< the list of Phi instruction */
57 ir_node **df_list; /**< the list of data flow instruction */
58 ir_node **cf_list; /**< the list of control flow instructions */
59 ir_node **entry_list; /**< list of all block entries */
63 * compare two block_entries
65 static int addr_cmp(const void *elt, const void *key)
67 const block_entry_t *e1 = (const block_entry_t*)elt;
68 const block_entry_t *e2 = (const block_entry_t*)key;
70 return e1->block != e2->block;
74 * Returns the associates block_entry_t for an block
76 static block_entry_t *block_find_entry(ir_node *block, blk_collect_data_t *ctx)
82 elem = (block_entry_t*)pset_find(ctx->blk_map, &key, HASH_PTR(block));
86 elem = OALLOC(&ctx->obst, block_entry_t);
89 elem->phi_list = NEW_ARR_F(ir_node *, 0);
90 elem->df_list = NEW_ARR_F(ir_node *, 0);
91 elem->cf_list = NEW_ARR_F(ir_node *, 0);
92 elem->entry_list = NEW_ARR_F(ir_node *, 0);
94 return (block_entry_t*)pset_insert(ctx->blk_map, elem, HASH_PTR(block));
98 * Traverse a block in pre order.
100 static void traverse_block_pre(ir_node *block, block_entry_t *entry, irg_walk_func *pre, void *env)
104 for (j = ARR_LEN(entry->cf_list); j > 0;) {
105 ir_node *node = entry->cf_list[--j];
109 for (j = ARR_LEN(entry->df_list); j > 0;) {
110 ir_node *node = entry->df_list[--j];
114 for (j = ARR_LEN(entry->phi_list); j > 0;) {
115 ir_node *node = entry->phi_list[--j];
123 * Traverse a block in post order.
125 static void traverse_block_post(ir_node *block, block_entry_t *entry,
126 irg_walk_func *post, void *env)
132 for (j = 0, n = ARR_LEN(entry->phi_list); j < n; ++j) {
133 ir_node *node = entry->phi_list[j];
137 for (j = 0, n = ARR_LEN(entry->df_list); j < n; ++j) {
138 ir_node *node = entry->df_list[j];
142 for (j = 0, n = ARR_LEN(entry->cf_list); j < n; ++j) {
143 ir_node *node = entry->cf_list[j];
149 * traverse the pre order only, from End to Start
151 static void traverse_pre(blk_collect_data_t *blks, irg_walk_func *pre, void *env)
155 for (i = ARR_LEN(blks->blk_list); i > 0;) {
156 ir_node *block = blks->blk_list[--i];
157 block_entry_t *entry = block_find_entry(block, blks);
159 traverse_block_pre(block, entry, pre, env);
161 DEL_ARR_F(entry->entry_list);
162 DEL_ARR_F(entry->phi_list);
163 DEL_ARR_F(entry->df_list);
164 DEL_ARR_F(entry->cf_list);
169 * traverse the post order only, from Start to End
171 static void traverse_post(blk_collect_data_t *blks, irg_walk_func *post, void *env)
175 for (i = 0, k = ARR_LEN(blks->blk_list); i < k; ++i) {
176 ir_node *block = blks->blk_list[i];
177 block_entry_t *entry = block_find_entry(block, blks);
179 traverse_block_post(block, entry, post, env);
181 DEL_ARR_F(entry->entry_list);
182 DEL_ARR_F(entry->phi_list);
183 DEL_ARR_F(entry->df_list);
184 DEL_ARR_F(entry->cf_list);
191 static void traverse_both(blk_collect_data_t *blks, irg_walk_func *pre, irg_walk_func *post, void *env)
195 for (i = ARR_LEN(blks->blk_list); i > 0;) {
196 ir_node *block = blks->blk_list[--i];
197 block_entry_t *entry = block_find_entry(block, blks);
199 traverse_block_pre(block, entry, pre, env);
203 traverse_post(blks, post, env);
209 static void traverse_blocks(blk_collect_data_t *blks, irg_walk_func *pre, irg_walk_func *post, void *env)
211 if (!post) traverse_pre (blks, pre, env);
212 else if (!pre) traverse_post(blks, post, env);
213 else traverse_both(blks, pre, post, env);
216 typedef struct dom_traversal_t {
217 blk_collect_data_t *blks;
224 * Dom block walker. Visit all nodes in pre oder.
226 static void dom_block_visit_pre(ir_node *block, void *env)
228 dom_traversal_t *ctx = (dom_traversal_t*)env;
229 block_entry_t *entry = block_find_entry(block, ctx->blks);
231 traverse_block_pre(block, entry, ctx->pre, ctx->env);
235 * Dom block walker. Visit all nodes in post oder.
237 static void dom_block_visit_post(ir_node *block, void *env)
239 dom_traversal_t *ctx = (dom_traversal_t*)env;
240 block_entry_t *entry = block_find_entry(block, ctx->blks);
242 traverse_block_post(block, entry, ctx->post, ctx->env);
246 * Dom block walker. Visit all nodes in pre oder, than in post order.
248 static void dom_block_visit_both(ir_node *block, void *env)
250 dom_traversal_t *ctx = (dom_traversal_t*)env;
251 block_entry_t *entry = block_find_entry(block, ctx->blks);
253 traverse_block_pre(block, entry, ctx->pre, ctx->env);
254 traverse_block_post(block, entry, ctx->post, ctx->env);
258 * Do the traversal in the dominator tree in top-down order.
260 static void traverse_dom_blocks_top_down(blk_collect_data_t* blks, irg_walk_func *pre, irg_walk_func *post, void *env)
269 if (pre != NULL && post != NULL)
270 dom_tree_walk_irg(current_ir_graph, dom_block_visit_both, NULL, &ctx);
271 else if (pre != NULL)
272 dom_tree_walk_irg(current_ir_graph, dom_block_visit_pre, NULL, &ctx);
273 else if (post != NULL)
274 dom_tree_walk_irg(current_ir_graph, dom_block_visit_post, NULL, &ctx);
278 * walks over the graph and collects all blocks and all block entries
280 static void collect_walk(ir_node *node, blk_collect_data_t *env)
283 block_entry_t *entry;
286 mark_irn_visited(node);
288 if (is_Block(node)) {
289 /* predecessors of a block are control flow nodes */
290 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
291 ir_node *pred = _get_walk_irn_n(env, node, i);
292 ir_node *blk = get_nodes_block(pred);
294 if (!irn_visited(pred)) {
295 collect_walk(pred, env);
297 /* control flow predecessors are always block inputs */
298 entry = block_find_entry(blk, env);
299 ARR_APP1(ir_node *, entry->entry_list, pred);
303 /* it's a block, put it into the block list */
304 if (node == get_irg_end_block(current_ir_graph)) {
305 /* Put the end block always last. If we don't do it here,
306 * it might be placed elsewhere if the graph contains
310 ARR_APP1(ir_node *, env->blk_list, node);
314 block = get_nodes_block(node);
316 if (!irn_visited(block))
317 collect_walk(block, env);
319 is_phi = is_Phi(node);
320 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
321 ir_node *pred = _get_walk_irn_n(env, node, i);
323 if (!irn_visited(pred)) {
324 collect_walk(pred, env);
326 /* BEWARE: predecessors of End nodes might be blocks */
327 if (!is_Block(pred)) {
328 ir_node *blk = get_nodes_block(pred);
331 * Note that Phi predecessors are always block entries
332 * because Phi edges are always "outside" a block
334 if (block != blk || is_phi) {
335 entry = block_find_entry(blk, env);
336 ARR_APP1(ir_node *, entry->entry_list, pred);
345 * walks over the nodes of a block
346 * and collects them into the right list
348 static void collect_blks_lists(ir_node *node, ir_node *block,
349 block_entry_t *entry, blk_collect_data_t *env)
353 mark_irn_visited(node);
356 * Do not descent into Phi predecessors, these are always
357 * outside the current block because Phi edges are always
360 if (! is_Phi(node)) {
361 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
362 ir_node *pred = _get_walk_irn_n(env, node, i);
364 /* BEWARE: predecessors of End nodes might be blocks */
365 if (!is_Block(pred)) {
366 ir_node *blk = get_nodes_block(pred);
368 if (!irn_visited(pred)) {
371 collect_blks_lists(pred, block, entry, env);
376 ARR_APP1(ir_node *, entry->phi_list, node);
380 if (get_irn_mode(node) == mode_X) {
381 ARR_APP1(ir_node *, entry->cf_list, node);
383 ARR_APP1(ir_node *, entry->df_list, node);
388 * walk over the graph and collect all lists
390 static void collect_lists(blk_collect_data_t *env)
393 ir_node *block, *node;
394 block_entry_t *entry;
396 inc_irg_visited(current_ir_graph);
398 for (i = ARR_LEN(env->blk_list); i > 0;) {
399 block = env->blk_list[--i];
400 entry = block_find_entry(block, env);
402 for (j = ARR_LEN(entry->entry_list); j > 0;) {
403 node = entry->entry_list[--j];
405 /* a entry might already be visited due to Phi loops */
406 if (node->visited < current_ir_graph->visited)
407 collect_blks_lists(node, block, entry, env);
413 * Intra procedural graph walker over blocks.
415 static void do_irg_walk_blk(ir_graph *irg, irg_walk_func *pre,
416 irg_walk_func *post, void *env, unsigned follow_deps,
417 void (*traverse)(blk_collect_data_t* blks, irg_walk_func *pre, irg_walk_func *post, void *env))
419 ir_node *end_node = get_irg_end(irg);
420 ir_node *end_blk = get_irg_end_block(irg);
421 blk_collect_data_t blks;
422 block_entry_t *entry;
424 obstack_init(&blks.obst);
425 blks.blk_map = new_pset(addr_cmp, 1);
426 blks.blk_list = NEW_ARR_F(ir_node *, 0);
427 blks.follow_deps = follow_deps != 0;
429 /* first step: traverse the graph and fill the lists */
430 ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
431 inc_irg_visited(irg);
432 collect_walk(end_node, &blks);
434 /* add the end block */
435 ARR_APP1(ir_node *, blks.blk_list, end_blk);
437 /* and the end node */
438 entry = block_find_entry(end_blk, &blks);
439 ARR_APP1(ir_node *, entry->entry_list, end_node);
441 collect_lists(&blks);
443 /* second step: traverse the list */
444 traverse(&blks, pre, post, env);
446 DEL_ARR_F(blks.blk_list);
447 del_pset(blks.blk_map);
448 obstack_free(&blks.obst, NULL);
450 ir_free_resources(irg, IR_RESOURCE_IRN_VISITED);
453 void irg_walk_blkwise_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env)
455 ir_graph * rem = current_ir_graph;
457 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
458 current_ir_graph = irg;
459 do_irg_walk_blk(irg, pre, post, env, 0, traverse_blocks);
460 current_ir_graph = rem;
463 void irg_walk_in_or_dep_blkwise_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env)
465 ir_graph * rem = current_ir_graph;
467 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
468 current_ir_graph = irg;
469 do_irg_walk_blk(irg, pre, post, env, 1, traverse_blocks);
470 current_ir_graph = rem;
473 void irg_walk_blkwise_dom_top_down(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env)
475 ir_graph * rem = current_ir_graph;
477 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
478 current_ir_graph = irg;
479 do_irg_walk_blk(irg, pre, post, env, 0, traverse_dom_blocks_top_down);
480 current_ir_graph = rem;