Fix a typo that was killing GVNPRE of select instructions.

llvm-svn: 37871

2 files changed, 10 insertions, 1 deletions

diff --git a/llvm/lib/Transforms/Scalar/GVNPRE.cpp b/llvm/lib/Transforms/Scalar/GVNPRE.cpp
index 33926ea127a..5d52aa48875 100644
--- a/llvm/lib/Transforms/Scalar/GVNPRE.cpp
+++ b/llvm/lib/Transforms/Scalar/GVNPRE.cpp
@@ -1040,7 +1040,7 @@ void GVNPRE::topo_sort(SmallPtrSet<Value*, 16>& set, std::vector<Value*>& vec) {
           stack.push_back(r);
         else if (m != 0 && isa<Instruction>(m) &&
                  visited.count(m) == 0)
-          stack.push_back(r);
+          stack.push_back(m);
         else {
           vec.push_back(e);
           visited.insert(e);
diff --git a/llvm/test/Transforms/GVNPRE/2007-07-04-CleanSelect.ll b/llvm/test/Transforms/GVNPRE/2007-07-04-CleanSelect.ll
new file mode 100644
index 00000000000..d72e2e1eb51
--- /dev/null
+++ b/llvm/test/Transforms/GVNPRE/2007-07-04-CleanSelect.ll
@@ -0,0 +1,9 @@
+; RUN: llvm-as < %s | opt -gvnpre | llvm-dis
+
+define i32* @_ZN6Solver9propagateEv(i32* %this) {
+entry:
+	%tmp15.i48 = load i8* null		; <i8> [#uses=2]
+	%tmp64.i.i51 = sub i8 0, %tmp15.i48		; <i8> [#uses=1]
+	%tmp231.i52 = select i1 false, i8 %tmp15.i48, i8 %tmp64.i.i51		; <i8> [#uses=0]
+	ret i32* null
+}