2 * Copyright (C) 1995-2008 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" /* visited flag */
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) {
66 const block_entry_t *e1 = elt;
67 const block_entry_t *e2 = 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 = pset_find(ctx->blk_map, &key, HASH_PTR(block));
85 elem = obstack_alloc(&ctx->obst, sizeof(*elem));
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 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) {
102 for (j = ARR_LEN(entry->cf_list) - 1; j >= 0; --j) {
103 ir_node *node = entry->cf_list[j];
107 for (j = ARR_LEN(entry->df_list) - 1; j >= 0; --j) {
108 ir_node *node = entry->df_list[j];
112 for (j = ARR_LEN(entry->phi_list) - 1; j >= 0; --j) {
113 ir_node *node = entry->phi_list[j];
121 * Traverse a block in post order.
123 void traverse_block_post(ir_node *block, block_entry_t *entry, irg_walk_func *post, void *env) {
128 for (j = 0, n = ARR_LEN(entry->phi_list); j < n; ++j) {
129 ir_node *node = entry->phi_list[j];
133 for (j = 0, n = ARR_LEN(entry->df_list); j < n; ++j) {
134 ir_node *node = entry->df_list[j];
138 for (j = 0, n = ARR_LEN(entry->cf_list); j < n; ++j) {
139 ir_node *node = entry->cf_list[j];
145 * traverse the pre order only, from End to Start
147 static void traverse_pre(blk_collect_data_t *blks, irg_walk_func *pre, void *env) {
150 for (i = ARR_LEN(blks->blk_list) - 1; i >= 0; --i) {
151 ir_node *block = blks->blk_list[i];
152 block_entry_t *entry = block_find_entry(block, blks);
154 traverse_block_pre(block, entry, pre, env);
156 DEL_ARR_F(entry->entry_list);
157 DEL_ARR_F(entry->phi_list);
158 DEL_ARR_F(entry->df_list);
159 DEL_ARR_F(entry->cf_list);
164 * traverse the post order only, from Start to End
166 static void traverse_post(blk_collect_data_t *blks, irg_walk_func *post, void *env) {
169 for (i = 0, k = ARR_LEN(blks->blk_list); i < k; ++i) {
170 ir_node *block = blks->blk_list[i];
171 block_entry_t *entry = block_find_entry(block, blks);
173 traverse_block_post(block, entry, post, env);
175 DEL_ARR_F(entry->entry_list);
176 DEL_ARR_F(entry->phi_list);
177 DEL_ARR_F(entry->df_list);
178 DEL_ARR_F(entry->cf_list);
185 static void traverse_both(blk_collect_data_t *blks, irg_walk_func *pre, irg_walk_func *post, void *env)
189 for (i = ARR_LEN(blks->blk_list) - 1; i >= 0; --i) {
190 ir_node *block = blks->blk_list[i];
191 block_entry_t *entry = block_find_entry(block, blks);
193 traverse_block_pre(block, entry, pre, env);
197 traverse_post(blks, post, env);
203 static void traverse_blocks(blk_collect_data_t *blks, irg_walk_func *pre, irg_walk_func *post, void *env) {
204 if (!post) traverse_pre (blks, pre, env);
205 else if (!pre) traverse_post(blks, post, env);
206 else traverse_both(blks, pre, post, env);
209 typedef struct dom_traversal_t {
210 blk_collect_data_t *blks;
217 * Dom block walker. Visit all nodes in pre oder.
219 static void dom_block_visit_pre(ir_node *block, void *env) {
220 dom_traversal_t *ctx = env;
221 block_entry_t *entry = block_find_entry(block, ctx->blks);
223 traverse_block_pre(block, entry, ctx->pre, ctx->env);
227 * Dom block walker. Visit all nodes in post oder.
229 static void dom_block_visit_post(ir_node *block, void *env) {
230 dom_traversal_t *ctx = env;
231 block_entry_t *entry = block_find_entry(block, ctx->blks);
233 traverse_block_post(block, entry, ctx->post, ctx->env);
237 * Dom block walker. Visit all nodes in pre oder, than in post order.
239 static void dom_block_visit_both(ir_node *block, void *env) {
240 dom_traversal_t *ctx = env;
241 block_entry_t *entry = block_find_entry(block, ctx->blks);
243 traverse_block_pre(block, entry, ctx->pre, ctx->env);
244 traverse_block_post(block, entry, ctx->post, ctx->env);
248 * Do the traversal in the dominator tree in top-down order.
250 static void traverse_dom_blocks_top_down(blk_collect_data_t* blks, irg_walk_func *pre, irg_walk_func *post, void *env) {
258 if (pre != NULL && post != NULL)
259 dom_tree_walk_irg(current_ir_graph, dom_block_visit_both, NULL, &ctx);
260 else if (pre != NULL)
261 dom_tree_walk_irg(current_ir_graph, dom_block_visit_pre, NULL, &ctx);
262 else if (post != NULL)
263 dom_tree_walk_irg(current_ir_graph, dom_block_visit_post, NULL, &ctx);
267 * walks over the graph and collects all blocks and all block entries
269 static void collect_walk(ir_node *node, blk_collect_data_t *env)
272 block_entry_t *entry;
275 mark_irn_visited(node);
277 if (node->op == op_Block) {
278 /* predecessors of a block are control flow nodes */
279 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
280 ir_node *pred = _get_walk_irn_n(env, node, i);
281 ir_node *blk = get_nodes_block(pred);
283 if (!irn_visited(pred)) {
284 collect_walk(pred, env);
286 /* control flow predecessors are always block inputs */
287 entry = block_find_entry(blk, env);
288 ARR_APP1(ir_node *, entry->entry_list, pred);
292 /* it's a block, put it into the block list */
293 if (node == get_irg_end_block(current_ir_graph)) {
294 /* Put the end block always last. If we don't do it here,
295 * it might be placed elsewhere if the graph contains
299 ARR_APP1(ir_node *, env->blk_list, node);
303 block = get_nodes_block(node);
305 if (!irn_visited(block))
306 collect_walk(block, env);
308 is_phi = is_Phi(node);
309 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
310 ir_node *pred = _get_walk_irn_n(env, node, i);
312 if (!irn_visited(pred)) {
313 collect_walk(pred, env);
315 /* BEWARE: predecessors of End nodes might be blocks */
316 if (is_no_Block(pred)) {
317 ir_node *blk = get_nodes_block(pred);
320 * Note that Phi predecessors are always block entries
321 * because Phi edges are always "outside" a block
323 if (block != blk || is_phi) {
324 entry = block_find_entry(blk, env);
325 ARR_APP1(ir_node *, entry->entry_list, pred);
334 * walks over the nodes of a block
335 * and collects them into the right list
337 static void collect_blks_lists(ir_node *node, ir_node *block,
338 block_entry_t *entry, blk_collect_data_t *env)
342 mark_irn_visited(node);
345 * Do not descent into Phi predecessors, these are always
346 * outside the current block because Phi edges are always
349 if (! is_Phi(node)) {
350 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
351 ir_node *pred = _get_walk_irn_n(env, node, i);
353 /* BEWARE: predecessors of End nodes might be blocks */
354 if (is_no_Block(pred)) {
355 ir_node *blk = get_nodes_block(pred);
357 if (!irn_visited(pred)) {
360 collect_blks_lists(pred, block, entry, env);
365 ARR_APP1(ir_node *, entry->phi_list, node);
369 if (get_irn_mode(node) == mode_X) {
370 ARR_APP1(ir_node *, entry->cf_list, node);
372 ARR_APP1(ir_node *, entry->df_list, node);
377 * walk over the graph and collect all lists
379 static void collect_lists(blk_collect_data_t *env)
382 ir_node *block, *node;
383 block_entry_t *entry;
385 inc_irg_visited(current_ir_graph);
387 for (i = ARR_LEN(env->blk_list) - 1; i >= 0; --i) {
388 block = env->blk_list[i];
389 entry = block_find_entry(block, env);
391 for (j = ARR_LEN(entry->entry_list) - 1; j >= 0; --j) {
392 node = entry->entry_list[j];
394 /* a entry might already be visited due to Phi loops */
395 if (node->visited < current_ir_graph->visited)
396 collect_blks_lists(node, block, entry, env);
402 * Intraprozedural graph walker over blocks.
405 do_irg_walk_blk(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env, unsigned follow_deps,
406 void (*traverse)(blk_collect_data_t* blks, irg_walk_func *pre, irg_walk_func *post, void *env))
408 ir_node *end_node = get_irg_end(irg);
409 ir_node *end_blk = get_irg_end_block(irg);
410 blk_collect_data_t blks;
411 block_entry_t *entry;
413 #ifdef INTERPROCEDURAL_VIEW
414 /* switch off interprocedural view */
415 int old_view = get_interprocedural_view();
416 set_interprocedural_view(0);
419 obstack_init(&blks.obst);
420 blks.blk_map = new_pset(addr_cmp, 1);
421 blks.blk_list = NEW_ARR_F(ir_node *, 0);
422 blks.follow_deps = follow_deps != 0;
424 /* first step: traverse the graph and fill the lists */
425 ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
426 inc_irg_visited(irg);
427 collect_walk(end_node, &blks);
429 /* add the end block */
430 ARR_APP1(ir_node *, blks.blk_list, end_blk);
432 /* and the end node */
433 entry = block_find_entry(end_blk, &blks);
434 ARR_APP1(ir_node *, entry->entry_list, end_node);
436 collect_lists(&blks);
438 /* second step: traverse the list */
439 traverse(&blks, pre, post, env);
441 DEL_ARR_F(blks.blk_list);
442 del_pset(blks.blk_map);
443 obstack_free(&blks.obst, NULL);
445 #ifdef INTERPROCEDURAL_VIEW
446 set_interprocedural_view(old_view);
448 ir_free_resources(irg, IR_RESOURCE_IRN_VISITED);
451 void irg_walk_blkwise_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
452 ir_graph * rem = current_ir_graph;
454 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
455 current_ir_graph = irg;
456 do_irg_walk_blk(irg, pre, post, env, 0, traverse_blocks);
457 current_ir_graph = rem;
460 void irg_walk_in_or_dep_blkwise_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
461 ir_graph * rem = current_ir_graph;
463 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
464 current_ir_graph = irg;
465 do_irg_walk_blk(irg, pre, post, env, 1, traverse_blocks);
466 current_ir_graph = rem;
469 void irg_walk_blkwise_dom_top_down(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
470 ir_graph * rem = current_ir_graph;
472 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
473 current_ir_graph = irg;
474 do_irg_walk_blk(irg, pre, post, env, 0, traverse_dom_blocks_top_down);
475 current_ir_graph = rem;