Handle constants in phi nodes properly. This fixes test/Transforms/GVNPRE/2007-06-18-ConstantInPhi.ll
llvm-svn: 37655
diff --git a/llvm/lib/Transforms/Scalar/GVNPRE.cpp b/llvm/lib/Transforms/Scalar/GVNPRE.cpp
index 9b06664..15fecca 100644
--- a/llvm/lib/Transforms/Scalar/GVNPRE.cpp
+++ b/llvm/lib/Transforms/Scalar/GVNPRE.cpp
@@ -927,7 +927,16 @@
for (std::set<Value*>::iterator I = S.begin(), E = S.end();
I != E; ++I) {
- if (find_leader(anticIn, VN.lookup(*I)) == 0)
+ // For non-opaque values, we should already have a value numbering.
+ // However, for opaques, such as constants within PHI nodes, it is
+ // possible that they have not yet received a number. Make sure they do
+ // so now.
+ uint32_t valNum = 0;
+ if (isa<BinaryOperator>(*I) || isa<CmpInst>(*I))
+ valNum = VN.lookup(*I);
+ else
+ valNum = VN.lookup_or_add(*I);
+ if (find_leader(anticIn, valNum) == 0)
val_insert(anticIn, *I);
}