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 walker. Visit all nodes in pre oder.
221 static void dom_block_visit_pre(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 walker. Visit all nodes in post oder.
231 static void dom_block_visit_post(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 * Dom block walker. Visit all nodes in pre oder, than in post order.
241 static void dom_block_visit_both(ir_node *block, void *env) {
242 dom_traversal_t *ctx = env;
243 block_entry_t *entry = block_find_entry(block, ctx->blks);
245 traverse_block_pre(block, entry, ctx->pre, ctx->env);
246 traverse_block_post(block, entry, ctx->post, ctx->env);
250 * Do the traversal in the dominator tree in top-down order.
252 static void traverse_dom_blocks_top_down(blk_collect_data_t* blks, irg_walk_func *pre, irg_walk_func *post, void *env) {
260 if (pre != NULL && post != NULL)
261 dom_tree_walk_irg(current_ir_graph, dom_block_visit_both, NULL, &ctx);
262 else if (pre != NULL)
263 dom_tree_walk_irg(current_ir_graph, dom_block_visit_pre, NULL, &ctx);
264 else if (post != NULL)
265 dom_tree_walk_irg(current_ir_graph, dom_block_visit_post, NULL, &ctx);
269 * walks over the graph and collects all blocks and all block entries
271 static void collect_walk(ir_node *node, blk_collect_data_t *env)
274 block_entry_t *entry;
277 mark_irn_visited(node);
279 if (node->op == op_Block) {
280 /* predecessors of a block are control flow nodes */
281 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
282 ir_node *pred = _get_walk_irn_n(env, node, i);
283 ir_node *blk = get_nodes_block(pred);
285 if (!irn_visited(pred)) {
286 collect_walk(pred, env);
288 /* control flow predecessors are always block inputs */
289 entry = block_find_entry(blk, env);
290 ARR_APP1(ir_node *, entry->entry_list, pred);
294 /* it's a block, put it into the block list */
295 if (node == get_irg_end_block(current_ir_graph)) {
296 /* Put the end block always last. If we don't do it here,
297 * it might be placed elsewhere if the graph contains
301 ARR_APP1(ir_node *, env->blk_list, node);
305 block = get_nodes_block(node);
307 if (!irn_visited(block))
308 collect_walk(block, env);
310 is_phi = is_Phi(node);
311 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
312 ir_node *pred = _get_walk_irn_n(env, node, i);
314 if (!irn_visited(pred)) {
315 collect_walk(pred, env);
317 /* BEWARE: predecessors of End nodes might be blocks */
318 if (is_no_Block(pred)) {
319 ir_node *blk = get_nodes_block(pred);
322 * Note that Phi predecessors are always block entries
323 * because Phi edges are always "outside" a block
325 if (block != blk || is_phi) {
326 entry = block_find_entry(blk, env);
327 ARR_APP1(ir_node *, entry->entry_list, pred);
336 * walks over the nodes of a block
337 * and collects them into the right list
339 static void collect_blks_lists(ir_node *node, ir_node *block,
340 block_entry_t *entry, blk_collect_data_t *env)
344 mark_irn_visited(node);
347 * Do not descent into Phi predecessors, these are always
348 * outside the current block because Phi edges are always
351 if (! is_Phi(node)) {
352 for (i = _get_walk_arity(env, node) - 1; i >= 0; --i) {
353 ir_node *pred = _get_walk_irn_n(env, node, i);
355 /* BEWARE: predecessors of End nodes might be blocks */
356 if (is_no_Block(pred)) {
357 ir_node *blk = get_nodes_block(pred);
359 if (!irn_visited(pred)) {
362 collect_blks_lists(pred, block, entry, env);
367 ARR_APP1(ir_node *, entry->phi_list, node);
371 if (get_irn_mode(node) == mode_X) {
372 ARR_APP1(ir_node *, entry->cf_list, node);
374 ARR_APP1(ir_node *, entry->df_list, node);
379 * walk over the graph and collect all lists
381 static void collect_lists(blk_collect_data_t *env)
384 ir_node *block, *node;
385 block_entry_t *entry;
387 inc_irg_visited(current_ir_graph);
389 for (i = ARR_LEN(env->blk_list) - 1; i >= 0; --i) {
390 block = env->blk_list[i];
391 entry = block_find_entry(block, env);
393 for (j = ARR_LEN(entry->entry_list) - 1; j >= 0; --j) {
394 node = entry->entry_list[j];
396 /* a entry might already be visited due to Phi loops */
397 if (node->visited < current_ir_graph->visited)
398 collect_blks_lists(node, block, entry, env);
404 * Intraprozedural graph walker over blocks.
407 do_irg_walk_blk(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env, unsigned follow_deps,
408 void (*traverse)(blk_collect_data_t* blks, irg_walk_func *pre, irg_walk_func *post, void *env))
410 ir_node *end_node = get_irg_end(irg);
411 ir_node *end_blk = get_irg_end_block(irg);
412 blk_collect_data_t blks;
413 block_entry_t *entry;
415 #ifdef INTERPROCEDURAL_VIEW
416 /* switch off interprocedural view */
417 int old_view = get_interprocedural_view();
418 set_interprocedural_view(0);
421 obstack_init(&blks.obst);
422 blks.blk_map = new_pset(addr_cmp, 1);
423 blks.blk_list = NEW_ARR_F(ir_node *, 0);
424 blks.follow_deps = follow_deps != 0;
426 /* first step: traverse the graph and fill the lists */
427 ir_reserve_resources(irg, IR_RESOURCE_IRN_VISITED);
428 inc_irg_visited(irg);
429 collect_walk(end_node, &blks);
431 /* add the end block */
432 ARR_APP1(ir_node *, blks.blk_list, end_blk);
434 /* and the end node */
435 entry = block_find_entry(end_blk, &blks);
436 ARR_APP1(ir_node *, entry->entry_list, end_node);
438 collect_lists(&blks);
440 /* second step: traverse the list */
441 traverse(&blks, pre, post, env);
443 DEL_ARR_F(blks.blk_list);
444 del_pset(blks.blk_map);
445 obstack_free(&blks.obst, NULL);
447 #ifdef INTERPROCEDURAL_VIEW
448 set_interprocedural_view(old_view);
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) {
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) {
463 ir_graph * rem = current_ir_graph;
465 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
466 current_ir_graph = irg;
467 do_irg_walk_blk(irg, pre, post, env, 1, traverse_blocks);
468 current_ir_graph = rem;
471 void irg_walk_blkwise_dom_top_down(ir_graph *irg, irg_walk_func *pre, irg_walk_func *post, void *env) {
472 ir_graph * rem = current_ir_graph;
474 hook_irg_walk_blkwise(irg, (generic_func *)pre, (generic_func *)post);
475 current_ir_graph = irg;
476 do_irg_walk_blk(irg, pre, post, env, 0, traverse_dom_blocks_top_down);
477 current_ir_graph = rem;