From: Götz Lindenmaier <goetz@ipd.info.uni-karlsruhe.de>
Date: Thu, 9 Jan 2003 16:57:20 +0000 (+0000)
Subject: Added functiuon "remove critical edges" to be implemented.
X-Git-Url: http://nsz.repo.hu/git/?a=commitdiff_plain;h=7c628e72d36fb4e6042d93679383b83a41fc233d;p=libfirm

Added functiuon "remove critical edges" to be implemented.

[r588]
---

diff --git a/ir/ir/irgopt.c b/ir/ir/irgopt.c
index cb8a73154..6f0f7389b 100644
--- a/ir/ir/irgopt.c
+++ b/ir/ir/irgopt.c
@@ -1453,3 +1453,12 @@ void optimize_cf(ir_graph *irg) {
 
   current_ir_graph = rem;
 }
+
+/* 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). */
+void remove_critical_cf_edges(ir_graph *irg) {
+  printf("WARNING: called unimplemented function!!!\n");
+}
diff --git a/ir/ir/irgopt.h b/ir/ir/irgopt.h
index f03fceec8..6817c69b6 100644
--- a/ir/ir/irgopt.h
+++ b/ir/ir/irgopt.h
@@ -81,10 +81,11 @@ void inline_small_irgs(ir_graph *irg, int size);
    in state dom_consistent.  Destroys the out information as it moves nodes
    to other blocks.  Optimizes Tuples in Control edges. (@@@ This
    is not tested!)
+   Call remove_critical_cf_edges() before place_code().  This normalizes
+   the control flow graph so that for all operations a basic block exists
+   where they can be optimally placed.
    @@@ A more powerful code placement would move operations past Phi nodes
-   out of loops.  Further the control flow should be normalized before
-   computing the dominator information so that there exists an optimal block
-   for all operations. */
+   out of loops.  */
 void place_code(ir_graph *irg);
 
 /********************************************************************/
@@ -100,4 +101,12 @@ void place_code(ir_graph *irg);
 /********************************************************************/
 void optimize_cf(ir_graph *irg);
 
+/* Places 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).
+   @@@ not yet implemented!!! */
+void remove_critical_cf_edges(ir_graph *irg);
+
 # endif /* _IRGOPT_H_ */