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
31 #include "irgraph_t.h" /* visited flag */
38 #define _get_walk_arity(env, node) \
39 ((env)->follow_deps ? get_irn_ins_or_deps((node)) : get_irn_arity((node)))
40 #define _get_walk_irn_n(env, node, pos) \
41 ((env)->follow_deps ? get_irn_in_or_dep((node), (pos)) : get_irn_n((node), (pos)))
44 * Metadata for block walker
46 typedef struct _blk_collect_data_t {
47 struct obstack obst; /**< obstack to allocate objects on */
48 pset *blk_map; /**< Hash map: Block -> List */
49 ir_node **blk_list; /**< the Block list */
50 unsigned follow_deps : 1; /**< follow dependency edges */
54 * An entry for a block in the blk_map
56 typedef struct _block_entry_t {
57 ir_node *block; /**< the block */
58 ir_node **phi_list; /**< the list of Phi instruction */
59 ir_node **df_list; /**< the list of data flow instruction */
60 ir_node **cf_list; /**< the list of control flow instructions */
61 ir_node **entry_list; /**< list of all block entries */
65 * compare two block_entries
67 static int addr_cmp(const void *elt, const void *key) {
68 const block_entry_t *e1 = elt;
69 const block_entry_t *e2 = key;
71 return e1->block != e2->block;
75 * Returns the associates block_entry_t for an block
77 static block_entry_t *block_find_entry(ir_node *block, blk_collect_data_t *ctx)
83 elem = pset_find(ctx->blk_map, &key, HASH_PTR(block));
87 elem = obstack_alloc(&ctx->obst, sizeof(*elem));
90 elem->phi_list = NEW_ARR_F(ir_node *, 0);
91 elem->df_list = NEW_ARR_F(ir_node *, 0);
92 elem->cf_list = NEW_ARR_F(ir_node *, 0);
93 elem->entry_list = NEW_ARR_F(ir_node *, 0);
95 return pset_insert(ctx->blk_map, elem, HASH_PTR(block));
99 * Traverse a block in pre order.
101 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) - 1; j >= 0; --j) {
105 ir_node *node = entry->cf_list[j];
109 for (j = ARR_LEN(entry->df_list) - 1; j >= 0; --j) {
110 ir_node *node = entry->df_list[j];
114 for (j = ARR_LEN(entry->phi_list) - 1; j >= 0; --j) {
115 ir_node *node = entry->phi_list[j];
123 * Traverse a block in post order.
125 void traverse_block_post(ir_node *block, block_entry_t *entry, irg_walk_func *post, void *env) {
130 for (j = 0, n = ARR_LEN(entry->phi_list); j < n; ++j) {
131 ir_node *node = entry->phi_list[j];
135 for (j = 0, n = ARR_LEN(entry->df_list); j < n; ++j) {
136 ir_node *node = entry->df_list[j];
140 for (j = 0, n = ARR_LEN(entry->cf_list); j < n; ++j) {
141 ir_node *node = entry->cf_list[j];
147 * traverse the pre order only, from End to Start
149 static void traverse_pre(blk_collect_data_t *blks, irg_walk_func *pre, void *env) {
152 for (i = ARR_LEN(blks->blk_list) - 1; i >= 0; --i) {
153 ir_node *block = blks->blk_list[i];
154 block_entry_t *entry = block_find_entry(block, blks);
156 traverse_block_pre(block, entry, pre, env);
158 DEL_ARR_F(entry->entry_list);
159 DEL_ARR_F(entry->phi_list);
160 DEL_ARR_F(entry->df_list);
161 DEL_ARR_F(entry->cf_list);
166 * traverse the post order only, from Start to End
168 static void traverse_post(blk_collect_data_t *blks, irg_walk_func *post, void *env) {
171 for (i = 0, k = ARR_LEN(blks->blk_list); i < k; ++i) {
172 ir_node *block = blks->blk_list[i];
173 block_entry_t *entry = block_find_entry(block, blks);
175 traverse_block_post(block, entry, post, env);
177 DEL_ARR_F(entry->entry_list);
178 DEL_ARR_F(entry->phi_list);
179 DEL_ARR_F(entry->df_list);
180 DEL_ARR_F(entry->cf_list);
187 static void traverse_both(blk_collect_data_t *blks, irg_walk_func *pre, irg_walk_func *post, void *env)
191 for (i = ARR_LEN(blks->blk_list) - 1; i >= 0; --i) {
192 ir_node *block = blks->blk_list[i];
193 block_entry_t *entry = block_find_entry(block, blks);
195 traverse_block_pre(block, entry, pre, env);
199 traverse_post(blks, post, env);
205 static void traverse_blocks(blk_collect_data_t *blks, irg_walk_func *pre, irg_walk_func *post, void *env) {
206 if (!post) traverse_pre (blks, pre, env);
207 else if (!pre) traverse_post(blks, post, env);
208 else traverse_both(blks, pre, post, env);
211 typedef struct dom_traversal_t {
212 blk_collect_data_t *blks;
219 * Dom block pre walker.
221 static void pre_block_visit(ir_node *block, void *env) {
222 dom_traversal_t *ctx = env;
223 block_entry_t *entry = block_find_entry(block, ctx->blks);
225 traverse_block_pre(block, entry, ctx->pre, ctx->env);
229 * Dom block post walker.
231 static void post_block_visit(ir_node *block, void *env) {
232 dom_traversal_t *ctx = env;
233 block_entry_t *entry = block_find_entry(block, ctx->blks);
235 traverse_block_post(block, entry, ctx->post, ctx->env);
239 * Do the traversal in the dominator tree.
241 static void traverse_dom_blocks(blk_collect_data_t* blks, irg_walk_func *pre, irg_walk_func *post, void *env) {
249 dom_tree_walk_irg(current_ir_graph,
250 pre != NULL ? pre_block_visit : NULL,
251 post != NULL ? post_block_visit : NULL,
256 * walks over the graph and collects all blocks and all block entries
258 static void collect_walk(ir_node *node, blk_collect_data_t *env)
261 block_entry_t *entry;
264 mark_irn_visited(node);
266 if (node->op == op_Block) {
267 /* predecessors of a block are control flow nodes */
268 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
269 ir_node *pred = _get_walk_irn_n(env, node, i);
270 ir_node *blk = get_nodes_block(pred);
272 if (!irn_visited(pred)) {
273 collect_walk(pred, env);
275 /* control flow predecessors are always block inputs */
276 entry = block_find_entry(blk, env);
277 ARR_APP1(ir_node *, entry->entry_list, pred);
281 /* it's a block, put it into the block list */
282 if (node == get_irg_end_block(current_ir_graph)) {
283 /* Put the end block always last. If we don't do it here,
284 * it might be placed elsewhere if the graph contains
288 ARR_APP1(ir_node *, env->blk_list, node);
292 block = get_nodes_block(node);
294 if (!irn_visited(block))
295 collect_walk(block, env);
297 is_phi = is_Phi(node);
298 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
299 ir_node *pred = _get_walk_irn_n(env, node, i);
301 if (!irn_visited(pred)) {
302 collect_walk(pred, env);
304 /* BEWARE: predecessors of End nodes might be blocks */
305 if (is_no_Block(pred)) {
306 ir_node *blk = get_nodes_block(pred);
309 * Note that Phi predecessors are always block entries
310 * because Phi edges are always "outside" a block
312 if (block != blk || is_phi) {
313 entry = block_find_entry(blk, env);
314 ARR_APP1(ir_node *, entry->entry_list, pred);
323 * walks over the nodes of a block
324 * and collects them into the right list
326 static void collect_blks_lists(ir_node *node, ir_node *block,
327 block_entry_t *entry, blk_collect_data_t *env)
331 mark_irn_visited(node);
334 * Do not descent into Phi predecessors, these are always
335 * outside the current block because Phi edges are always
338 if (! is_Phi(node)) {
339 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
340 ir_node *pred = _get_walk_irn_n(env, node, i);
342 /* BEWARE: predecessors of End nodes might be blocks */
343 if (is_no_Block(pred)) {
344 ir_node *blk = get_nodes_block(pred);
346 if (!irn_visited(pred)) {
349 collect_blks_lists(pred, block, entry, env);
354 ARR_APP1(ir_node *, entry->phi_list, node);
358 if (get_irn_mode(node) == mode_X) {
359 ARR_APP1(ir_node *, entry->cf_list, node);
361 ARR_APP1(ir_node *, entry->df_list, node);
366 * walk over the graph and collect all lists
368 static void collect_lists(blk_collect_data_t *env)
371 ir_node *block, *node;
372 block_entry_t *entry;
374 inc_irg_visited(current_ir_graph);
376 for (i = ARR_LEN(env->blk_list) - 1; i >= 0; --i) {
377 block = env->blk_list[i];
378 entry = block_find_entry(block, env);
380 for (j = ARR_LEN(entry->entry_list) - 1; j >= 0; --j) {
381 node = entry->entry_list[j];
383 /* a entry might already be visited due to Phi loops */
384 if (node->visited < current_ir_graph->visited)
385 collect_blks_lists(node, block, entry, env);
391 * Intraprozedural graph walker over blocks.
394 do_irg_walk_blk(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env, unsigned follow_deps,
395 void (*traverse)(blk_collect_data_t* blks, irg_walk_func *pre, irg_walk_func *post, void *env))
397 ir_node *end_node = get_irg_end(irg);
398 ir_node *end_blk = get_irg_end_block(irg);
399 blk_collect_data_t blks;
400 block_entry_t *entry;
402 #ifdef INTERPROCEDURAL_VIEW
403 /* switch off interprocedural view */
404 int old_view = get_interprocedural_view();
405 set_interprocedural_view(0);
408 obstack_init(&blks.obst);
409 blks.blk_map = new_pset(addr_cmp, 1);
410 blks.blk_list = NEW_ARR_F(ir_node *, 0);
411 blks.follow_deps = follow_deps != 0;
413 /* first step: traverse the graph and fill the lists */
414 ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
415 inc_irg_visited(irg);
416 collect_walk(end_node, &blks);
418 /* add the end block */
419 ARR_APP1(ir_node *, blks.blk_list, end_blk);
421 /* and the end node */
422 entry = block_find_entry(end_blk, &blks);
423 ARR_APP1(ir_node *, entry->entry_list, end_node);
425 collect_lists(&blks);
427 /* second step: traverse the list */
428 traverse(&blks, pre, post, env);
430 DEL_ARR_F(blks.blk_list);
431 del_pset(blks.blk_map);
432 obstack_free(&blks.obst, NULL);
434 #ifdef INTERPROCEDURAL_VIEW
435 set_interprocedural_view(old_view);
437 ir_free_resources(irg, IR_RESOURCE_IRN_VISITED);
440 void irg_walk_blkwise_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
441 ir_graph * rem = current_ir_graph;
443 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
444 current_ir_graph = irg;
445 do_irg_walk_blk(irg, pre, post, env, 0, traverse_blocks);
446 current_ir_graph = rem;
449 void irg_walk_in_or_dep_blkwise_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
450 ir_graph * rem = current_ir_graph;
452 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
453 current_ir_graph = irg;
454 do_irg_walk_blk(irg, pre, post, env, 1, traverse_blocks);
455 current_ir_graph = rem;
458 void irg_walk_blkwise_dom_graph(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
459 ir_graph * rem = current_ir_graph;
461 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
462 current_ir_graph = irg;
463 do_irg_walk_blk(irg, pre, post, env, 0, traverse_dom_blocks);
464 current_ir_graph = rem;