From: Götz Lindenmaier <goetz@ipd.info.uni-karlsruhe.de>
Date: Wed, 5 Feb 2003 17:08:57 +0000 (+0000)
Subject: Implemented remove_critical_cf_edges.
X-Git-Url: http://nsz.repo.hu/git/?a=commitdiff_plain;h=c51e8a74bfdcc8d754de80c2ecf2184c83046ad3;p=libfirm

Implemented remove_critical_cf_edges.

[r741]
---

diff --git a/ir/ir/irgopt.c b/ir/ir/irgopt.c
index 287ef9fed..eac14d949 100644
--- a/ir/ir/irgopt.c
+++ b/ir/ir/irgopt.c
@@ -1453,11 +1453,44 @@ void optimize_cf(ir_graph *irg) {
   current_ir_graph = rem;
 }
 
-/* Placed an empty basic block on critical control flow edges thereby
+
+/* Called by walker of remove_critical_cf_edges. */
+void walk_critical_cf_edges(ir_node *n, void *env) {
+  int arity, i;
+  ir_node *pre, *block, **in, *jmp;
+
+  /* Block has multiple predecessors */
+  if ((op_Block == get_irn_op(n)) &&
+      (get_irn_arity(n) > 1)) {
+    arity = get_irn_arity(n);
+
+    for (i=0; i<arity; i++) {
+      pre = get_irn_n(n, i);
+      /* Predecessor has multiple sucessors. Insert new flow edge */
+      if ((NULL != pre) && (op_Proj == get_irn_op(pre))) {
+	/* set predeseccor arry for new block */
+	in = NEW_ARR_D (ir_node *, current_ir_graph->obst, 1);
+	/* set predecessor of new block */
+	in[0] = pre;
+	block = new_Block(1, in);
+	/* insert new jmp to new block */
+	switch_block(block);
+	jmp = new_Jmp();
+	switch_block(n);
+	/* set sucessor of new block */
+	set_irn_n(n, i, jmp);
+      } /* predecessor has multiple sucessors */
+    } /* for all predecessors */
+  } /* n is a block */
+}
+
+/** Placed an empty basic block on critical control flow edges thereby
    removing them.
    A critical control flow edge is an edge from a block with several
    control exits to a block with several control entries (See Muchnic
-   p. 407). */
+   p. 407).
+   @param irg IR Graph
+*/
 void remove_critical_cf_edges(ir_graph *irg) {
-  printf("WARNING: called unimplemented function!!!\n");
+  irg_walk_graph(irg, NULL, walk_critical_cf_edges, NULL);
 }