#include "irnode_t.h"
#include "ircons_t.h"
+#define get_dom_info(bl) (&(bl)->attr.block.dom)
+
+
/*--------------------------------------------------------------------*/
/** Accessing the dominator data structures **/
/*--------------------------------------------------------------------*/
-ir_node *get_Block_idom(ir_node *bl) {
- assert(get_irn_op(bl) == op_Block);
+ir_node *get_Block_idom(const ir_node *bl) {
+ assert(is_Block(bl));
if (get_Block_dom_depth(bl) == -1) {
/* This block is not reachable from Start */
return new_Bad();
}
- return bl->attr.block.dom.idom;
+ return get_dom_info(bl)->idom;
}
void set_Block_idom(ir_node *bl, ir_node *n) {
+ dom_info *bli = get_dom_info(bl);
+
assert(get_irn_op(bl) == op_Block);
- bl->attr.block.dom.idom = n;
+
+ /* Set the immediate dominator of bl to n */
+ bli->idom = n;
+
+ /*
+ * If we don't set the root of the dominator tree
+ * Append bl to the dominates queue of n.
+ */
+ if(n != NULL) {
+ dom_info *ni = get_dom_info(n);
+
+ bli->next = ni->first;
+ ni->first = bl;
+ }
}
-int get_Block_pre_num(ir_node *bl) {
+int get_Block_pre_num(const ir_node *bl) {
assert(get_irn_op(bl) == op_Block);
return bl->attr.block.dom.pre_num;
}
bl->attr.block.dom.pre_num = num;
}
-int get_Block_dom_depth(ir_node *bl) {
+int get_Block_dom_depth(const ir_node *bl) {
assert(get_irn_op(bl) == op_Block);
return bl->attr.block.dom.dom_depth;
}
bl->attr.block.dom.dom_depth = depth;
}
+unsigned get_Block_dom_tree_pre_num(const ir_node *bl)
+{
+ assert(is_Block(bl));
+ return get_dom_info(bl)->tree_pre_num;
+}
+
+unsigned get_Block_dom_max_subtree_pre_num(const ir_node *bl)
+{
+ assert(is_Block(bl));
+ return get_dom_info(bl)->max_subtree_pre_num;
+}
+
+int block_dominates(const ir_node *a, const ir_node *b)
+{
+ const dom_info *ai, *bi;
+
+ assert(is_Block(a) && is_Block(b));
+ ai = get_dom_info(a);
+ bi = get_dom_info(b);
+ return bi->tree_pre_num - ai->tree_pre_num
+ <= ai->max_subtree_pre_num - ai->tree_pre_num;
+}
+
+ir_node *get_Block_dominated_first(const ir_node *bl)
+{
+ assert(is_Block(bl));
+ return get_dom_info(bl)->first;
+}
+
+ir_node *get_Block_dominated_next(const ir_node *bl)
+{
+ assert(is_Block(bl));
+ return get_dom_info(bl)->next;
+}
+
+void dom_tree_walk(ir_node *n, irg_walk_func *pre,
+ irg_walk_func *post, void *env)
+{
+ ir_node *p;
+
+ assert(get_irn_irg(n)->dom_state == dom_consistent
+ && "The dominators of the irg must be consistent");
+
+ for(p = get_dom_info(p)->first; p; p = get_dom_info(p)->next) {
+ if(pre)
+ pre(p, env);
+
+ dom_tree_walk(p, pre, post, env);
+
+ if(post)
+ post(p, env);
+ }
+}
+
+void dom_tree_walk_irg(ir_graph *irg, irg_walk_func *pre,
+ irg_walk_func *post, void *env)
+{
+ /* The root of the dominator tree should be the start node. */
+ ir_node *root = get_irg_start_block(irg);
+
+ assert(irg->dom_state == dom_consistent
+ && "The dominators of the irg must be consistent");
+ assert(root && "The start block of the graph is NULL?");
+ assert(get_dom_info(root)->idom == NULL
+ && "The start node in the graph must be the root of the dominator tree");
+ dom_tree_walk(root, pre, post, env);
+}
+
+static void assign_tree_pre_order(ir_node *bl, void *data)
+{
+ unsigned *num = data;
+ dom_info *bi = get_dom_info(bl);
+ bi->tree_pre_num = (*num)++;
+}
+static void assign_tree_pre_order_max(ir_node *bl, void *data)
+{
+ dom_info *bi = get_dom_info(bl);
+ ir_node *p;
+ unsigned max = 0;
+
+ for(p = bi->first; p; p = get_dom_info(p)->next) {
+ unsigned max_p = get_dom_info(p)->max_subtree_pre_num;
+ max = max > max_p ? max : max_p;
+ }
+
+ bi->max_subtree_pre_num = max;
+}
/*--------------------------------------------------------------------*/
/* Building and Removing the dominator datastructure */
/* clean up */
/* free(tdi_list); @@@ does not work !!?? */
current_ir_graph = rem;
+
+ /* Do a walk over the tree and assign the tree pre orders. */
+ {
+ unsigned tree_pre_order = 0;
+ dom_tree_walk_irg(irg, assign_tree_pre_order,
+ assign_tree_pre_order_max, &tree_pre_order);
+ }
}
void free_dom_and_peace(ir_graph *irg) {
# define _IRDOM_H_
# include "irgraph.h"
+# include "irgwalk.h"
# include "irnode.h"
*
* If the block is not reachable from Start, returns a Bad node.
*/
-ir_node *get_Block_idom(ir_node *bl);
+ir_node *get_Block_idom(const ir_node *bl);
void set_Block_idom(ir_node *bl, ir_node *n);
-int get_Block_dom_depth(ir_node *bl);
+int get_Block_dom_depth(const ir_node *bl);
void set_Block_dom_depth(ir_node *bl, int depth);
-int get_Block_pre_num(ir_node *bl);
+int get_Block_pre_num(const ir_node *bl);
void set_Block_pre_num(ir_node *bl, int num);
+/**
+ * Get the pre-order number of a block resulting from a dfs walk
+ * over the dominator tree.
+ * @param bl The block.
+ * @return The pre-order number.
+ */
+unsigned get_Block_dom_tree_pre_num(const ir_node *bl);
+
+/**
+ * Get the largest pre-order number found in the subtree of the
+ * dominator tree rooted at a given block.
+ * @param bl The block.
+ * @return The largest pre-order number of block's dominator subtree.
+ */
+unsigned get_Block_dom_max_subtree_pre_num(const ir_node *bl);
+
+/**
+ * Get the first node in the list of nodes dominated by a given block.
+ *
+ * Each node keeps a list of nodes which it immediately dominates. The
+ * nodes are queued using the @c next pointer in the @c dom_info struct.
+ * Each node keeps a head of this list using the pointer @c first in the
+ * same structure.
+ *
+ * @param bl The block for which to get the first node dominated by @c bl.
+ * @return The first node dominated by @p bl.
+ */
+ir_node *get_Block_dominated_first(const ir_node *bl);
+
+/**
+ * Get the next node in a list of nodes which are dominated by some
+ * other node.
+ * @see get_Block_dominated_first().
+ * @param dom The previous node.
+ * @return The next node in this list or NULL if it was the last.
+ */
+ir_node *get_Block_dominated_next(const ir_node *dom);
+
+/**
+ * Check, if a block dominates another block.
+ * @param a The first block.
+ * @param b The second block.
+ * @return 1, if @p a dominates @p b, else 0.
+ */
+int block_dominates(const ir_node *a, const ir_node *b);
+
+/**
+ * Visit all nodes in the dominator subtree of a given node.
+ * Call a pre-visitor before descending to the children and call a
+ * post-visitor after returning from them.
+ * @param n The node to start walking from.
+ * @param pre The pre-visitor callback.
+ * @param post The post-visitor callback.
+ * @param env Some custom data passed to the visitors.
+ */
+void dom_tree_walk(ir_node *n, irg_walk_func *pre,
+ irg_walk_func *post, void *env);
+
+
+/**
+ * Walk over the dominator tree of an irg starting at the root.
+ * @param irg The graph.
+ * @param pre A pre-visitor to call.
+ * @param post A post-visitor to call.
+ * @param env Some private data to give to the visitors.
+ */
+void dom_tree_walk_irg(ir_graph *irg, irg_walk_func *pre,
+ irg_walk_func *post, void *env);
/* ------------ Building and Removing the dominator datasturcture ----------- */
projects / libfirm / commitdiff