Make GVN iterative.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41078 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Transforms/Scalar/GVN.cpp b/lib/Transforms/Scalar/GVN.cpp
index 1e9b177..b618d77 100644
--- a/lib/Transforms/Scalar/GVN.cpp
+++ b/lib/Transforms/Scalar/GVN.cpp
@@ -671,6 +671,7 @@
DenseMap<BasicBlock*, Value*> &Phis,
bool top_level = false);
void dump(DenseMap<BasicBlock*, Value*>& d);
+ bool iterateOnFunction(Function &F);
};
char GVN::ID = 0;
@@ -944,7 +945,21 @@
// GVN::runOnFunction - This is the main transformation entry point for a
// function.
//
-bool GVN::runOnFunction(Function &F) {
+bool GVN::runOnFunction(Function& F) {
+ bool changed = false;
+ bool shouldContinue = true;
+
+ while (shouldContinue) {
+ shouldContinue = iterateOnFunction(F);
+ changed |= shouldContinue;
+ }
+
+ return changed;
+}
+
+
+// GVN::iterateOnFunction - Executes one iteration of GVN
+bool GVN::iterateOnFunction(Function &F) {
// Clean out global sets from any previous functions
VN.clear();
availableOut.clear();