- tmp_dom_info *tdi_list, int* used) {
- tmp_dom_info *tdi;
- int i;
-
- assert(get_irn_op(bl) == op_Block);
- if (get_irg_block_visited(current_ir_graph) == get_Block_block_visited(bl))
- return;
- mark_Block_block_visited(bl);
- set_Block_pre_num(bl, *used);
-
- tdi = &tdi_list[*used];
- ++(*used);
-
- tdi->semi = tdi;
- tdi->label = tdi;
- tdi->ancestor = NULL;
- tdi->bucket = NULL;
- tdi->parent = parent;
- tdi->block = bl;
-
- /* Iterate */
- for(i = 0; i < get_Block_n_cfg_outs(bl); i++) {
- ir_node *pred = get_Block_cfg_out(bl, i);
- assert(get_irn_opcode(pred) == iro_Block);
- init_tmp_dom_info(pred, tdi, tdi_list, used);
- }
-}
-
-static void
-dom_compress (tmp_dom_info *v)
-{
- assert (v->ancestor);
- if (v->ancestor->ancestor) {
- dom_compress (v->ancestor);
- if (v->ancestor->label->semi < v->label->semi) {
- v->label = v->ancestor->label;
- }
- v->ancestor = v->ancestor->ancestor;
- }
-}
-
-/* if V is a root, return v, else return the vertex u, not being the
- root, with minimum u->semi on the path from v to its root. */
-INLINE static tmp_dom_info*
-dom_eval (tmp_dom_info *v)
-{
- if (!v->ancestor) return v;
- dom_compress (v);
- return v->label;
-}
-
-/* make V W's ancestor */
-INLINE static void
-dom_link (tmp_dom_info *v, tmp_dom_info *w)
-{
- w->ancestor = v;
-}
-
-/* Computes the dominator trees. Sets a flag in irg to "dom_consistent".
- If the control flow of the graph is changed this flag must be set to
- "dom_inconsistent". */
-void compute_doms(ir_graph *irg) {
- ir_graph *rem = current_ir_graph;
- int n_blocks, used, i, j;
- tmp_dom_info *tdi_list; /* Ein Golf? */
-
- current_ir_graph = irg;
-
- /* Update graph state */
- assert(get_irg_phase_state(current_ir_graph) != phase_building);
- current_ir_graph->dom_state = dom_consistent;
-
- /* Count the number of blocks in the graph. */
- n_blocks = 0;
- irg_block_walk(get_irg_end(current_ir_graph), count_and_init_blocks, NULL, &n_blocks);
-
- /* Memory for temporary information. */
- tdi_list = xcalloc(n_blocks, sizeof(tdi_list[0]));
-
- /* We need the out datastructure. */
- if (current_ir_graph->outs_state != outs_consistent)
- compute_outs(current_ir_graph);
-
- /* this with a standard walker as passing the parent to the sons isn't
- simple. */
- used = 0;
- inc_irg_block_visited(current_ir_graph);
- init_tmp_dom_info(get_irg_start_block(current_ir_graph), NULL, tdi_list, &used);
- /* If not all blocks are reachable from Start by out edges this assertion
- fails.
- assert(used == n_blocks && "Precondition for dom construction violated"); */
- n_blocks = used;
-
-
- for (i = n_blocks-1; i > 0; i--) { /* Don't iterate the root, it's done. */
- int irn_arity;
- tmp_dom_info *w = &tdi_list[i];
- tmp_dom_info *v;
-
- /* Step 2 */
- irn_arity = get_irn_arity(w->block);
- for (j = 0; j < irn_arity; j++) {
- ir_node *cf_op = get_Block_cfgpred(w->block, j);
- ir_node *pred = get_nodes_block(cf_op);
- tmp_dom_info *u;
-
- if ((is_Bad(cf_op)) || (is_Bad(pred)) ||
- (get_Block_pre_num (pred) == -1))
- continue; /* control-dead */
-
- u = dom_eval (&tdi_list[get_Block_pre_num(pred)]);
- if (u->semi < w->semi) w->semi = u->semi;
- }
- /* Add w to w->semi's bucket. w is in exactly one bucket, so
- buckets can ben implemented as linked lists. */
- w->bucket = w->semi->bucket;
- w->semi->bucket = w;
-
- dom_link (w->parent, w);
-
- /* Step 3 */
- while (w->parent->bucket) {
- tmp_dom_info *u;
- v = w->parent->bucket;
- /* remove v from w->parent->bucket */
- w->parent->bucket = v->bucket;
- v->bucket = NULL;
-
- u = dom_eval (v);
- if (u->semi < v->semi)
- v->dom = u;
- else
- v->dom = w->parent;
- }
- }
- /* Step 4 */
- tdi_list[0].dom = NULL;
- memset(get_dom_info(tdi_list[0].block), 0, sizeof(dom_info));
- set_Block_idom(tdi_list[0].block, NULL);
- set_Block_dom_depth(tdi_list[0].block, 1);
- for (i = 1; i < n_blocks; i++) {
- tmp_dom_info *w = &tdi_list[i];
-
- if (w->dom != w->semi) w->dom = w->dom->dom;
- memset(get_dom_info(tdi_list[i].block), 0, sizeof(dom_info));
- set_Block_idom(w->block, w->dom->block);
- set_Block_dom_depth(w->block, get_Block_dom_depth(w->dom->block) + 1);
- }
-
- /* clean up */
- /* free(tdi_list); @@@ does not work !!?? */
- current_ir_graph = rem;
+ tmp_dom_info *tdi_list, int *used, int n_blocks)
+{
+ tmp_dom_info *tdi;
+ int i;
+
+ if (Block_block_visited(bl))
+ return;
+ mark_Block_block_visited(bl);
+ set_Block_dom_pre_num(bl, *used);
+
+ assert(*used < n_blocks);
+ tdi = &tdi_list[*used];
+ ++(*used);
+
+ tdi->semi = tdi;
+ tdi->label = tdi;
+ tdi->ancestor = NULL;
+ tdi->bucket = NULL;
+ tdi->parent = parent;
+ tdi->block = bl;
+
+ /* Iterate */
+ for (i = get_Block_n_cfg_outs_ka(bl) - 1; i >= 0; --i) {
+ ir_node *pred = get_Block_cfg_out_ka(bl, i);
+ /* can happen for half-optimized dead code (I've seen this in student
+ projects */
+ if (!is_Block(pred))
+ continue;
+
+ init_tmp_dom_info(pred, tdi, tdi_list, used, n_blocks);
+ }
+}
+
+/**
+ * Walks Blocks along the control flow. If recursion started with
+ * End block misses blocks in endless loops.
+ */
+static void init_tmp_pdom_info(ir_node *bl, tmp_dom_info *parent,
+ tmp_dom_info *tdi_list, int* used, int n_blocks)
+{
+ tmp_dom_info *tdi;
+ int i;
+
+ if (get_irg_block_visited(current_ir_graph) == get_Block_block_visited(bl))
+ return;
+ mark_Block_block_visited(bl);
+ set_Block_postdom_pre_num(bl, *used);
+
+ assert(*used < n_blocks);
+ tdi = &tdi_list[*used];
+ ++(*used);
+
+ tdi->semi = tdi;
+ tdi->label = tdi;
+ tdi->ancestor = NULL;
+ tdi->bucket = NULL;
+ tdi->parent = parent;
+ tdi->block = bl;
+
+ /* Iterate */
+ for (i = get_Block_n_cfgpreds(bl) - 1; i >= 0; --i) {
+ ir_node *pred = get_Block_cfgpred_block(bl, i);
+ if (is_Bad(pred))
+ continue;
+ init_tmp_pdom_info(pred, tdi, tdi_list, used, n_blocks);
+ }
+
+ /* Handle keep-alives. Note that the preprocessing
+ in init_construction() had already killed all
+ phantom keep-alive edges. All remaining block keep-alives
+ are really edges to endless loops.
+ */
+ if (bl == get_irg_end_block(current_ir_graph)) {
+ ir_node *end = get_irg_end(current_ir_graph);
+
+ for (i = get_irn_arity(end) - 1; i >= 0; --i) {
+ ir_node *pred = get_irn_n(end, i);
+
+ if (is_Block(pred))
+ init_tmp_pdom_info(pred, tdi, tdi_list, used, n_blocks);
+ }
+ }
+}
+
+static void dom_compress(tmp_dom_info *v)
+{
+ assert (v->ancestor);
+ if (v->ancestor->ancestor) {
+ dom_compress (v->ancestor);
+ if (v->ancestor->label->semi < v->label->semi) {
+ v->label = v->ancestor->label;
+ }
+ v->ancestor = v->ancestor->ancestor;
+ }
+}
+
+/**
+ * if V is a root, return v, else return the vertex u, not being the
+ * root, with minimum u->semi on the path from v to its root.
+ */
+inline static tmp_dom_info *dom_eval(tmp_dom_info *v)
+{
+ if (!v->ancestor) return v;
+ dom_compress (v);
+ return v->label;
+}
+
+/** make V W's ancestor */
+inline static void dom_link(tmp_dom_info *v, tmp_dom_info *w)
+{
+ w->ancestor = v;
+}
+
+/**
+ * Walker: count the number of blocks and clears the dominance info
+ */
+static void count_and_init_blocks_dom(ir_node *bl, void *env)
+{
+ int *n_blocks = (int *) env;
+
+ (*n_blocks) ++;
+
+ memset(get_dom_info(bl), 0, sizeof(ir_dom_info));
+ set_Block_idom(bl, NULL);
+ set_Block_dom_pre_num(bl, -1);
+ set_Block_dom_depth(bl, -1);
+}
+
+void compute_doms(ir_graph *irg)
+{
+ ir_graph *rem = current_ir_graph;
+ int n_blocks, used, i, j;
+ tmp_dom_info *tdi_list; /* Ein Golf? */
+
+ current_ir_graph = irg;
+
+ /* Update graph state */
+ assert(!irg_is_constrained(irg, IR_GRAPH_CONSTRAINT_CONSTRUCTION));
+
+ /* Count the number of blocks in the graph. */
+ n_blocks = 0;
+ irg_block_walk_graph(irg, count_and_init_blocks_dom, NULL, &n_blocks);
+
+ /* Memory for temporary information. */
+ tdi_list = XMALLOCNZ(tmp_dom_info, n_blocks);
+
+ /* We need the out data structure. */
+ assure_irg_outs(irg);
+
+ /* this with a standard walker as passing the parent to the sons isn't
+ simple. */
+ used = 0;
+ inc_irg_block_visited(irg);
+ init_tmp_dom_info(get_irg_start_block(irg), NULL, tdi_list, &used, n_blocks);
+ /* If not all blocks are reachable from Start by out edges this assertion
+ fails.
+ assert(used == n_blocks && "Precondition for dom construction violated"); */
+ assert(used <= n_blocks && "Precondition for dom construction violated");
+ n_blocks = used;
+
+
+ for (i = n_blocks-1; i > 0; i--) { /* Don't iterate the root, it's done. */
+ tmp_dom_info *w = &tdi_list[i];
+ ir_node *block = w->block;
+ tmp_dom_info *v;
+ int irn_arity;
+
+ /* Step 2 */
+ irn_arity = get_irn_arity(block);
+ for (j = 0; j < irn_arity; j++) {
+ ir_node *pred = get_Block_cfgpred(block, j);
+ ir_node *pred_block = get_nodes_block(pred);
+ tmp_dom_info *u;
+
+ if (is_Bad(pred) || (get_Block_dom_pre_num (pred_block) == -1))
+ continue; /* unreachable */
+
+ u = dom_eval (&tdi_list[get_Block_dom_pre_num(pred_block)]);
+ if (u->semi < w->semi)
+ w->semi = u->semi;
+ }
+
+ /* handle keep-alives if we are at the end block */
+ if (block == get_irg_end_block(irg)) {
+ ir_node *end = get_irg_end(irg);
+
+ irn_arity = get_irn_arity(end);
+ for (j = 0; j < irn_arity; j++) {
+ ir_node *pred = get_irn_n(end, j);
+ tmp_dom_info *u;
+
+ if (!is_Block(pred) || get_Block_dom_pre_num(pred) == -1)
+ continue; /* unreachable */
+
+ u = dom_eval (&tdi_list[get_Block_dom_pre_num(pred)]);
+ if (u->semi < w->semi)
+ w->semi = u->semi;
+ }
+ }
+
+ /* Add w to w->semi's bucket. w is in exactly one bucket, so
+ buckets can been implemented as linked lists. */
+ w->bucket = w->semi->bucket;
+ w->semi->bucket = w;
+
+ dom_link (w->parent, w);
+
+ /* Step 3 */
+ while (w->parent->bucket) {
+ tmp_dom_info *u;
+ v = w->parent->bucket;
+ /* remove v from w->parent->bucket */
+ w->parent->bucket = v->bucket;
+ v->bucket = NULL;
+
+ u = dom_eval (v);
+ if (u->semi < v->semi)
+ v->dom = u;
+ else
+ v->dom = w->parent;
+ }
+ }
+ /* Step 4 */
+ tdi_list[0].dom = NULL;
+ set_Block_idom(tdi_list[0].block, NULL);
+ set_Block_dom_depth(tdi_list[0].block, 1);
+ for (i = 1; i < n_blocks; i++) {
+ tmp_dom_info *w = &tdi_list[i];
+ int depth;
+
+ if (! w->dom)
+ continue; /* control dead */
+
+ if (w->dom != w->semi)
+ w->dom = w->dom->dom;
+ set_Block_idom(w->block, w->dom->block);
+
+ /* blocks dominated by dead one's are still dead */
+ depth = get_Block_dom_depth(w->dom->block);
+ if (depth > 0)
+ ++depth;
+ set_Block_dom_depth(w->block, depth);
+ }
+
+ /* clean up */
+ free(tdi_list);