From 8143c2bc0de4f39bef0432a25d9a111be4767fa1 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Sun, 17 Oct 2004 21:23:26 +0000 Subject: [PATCH] Enhance hasConstantValue to ignore undef values in phi nodes. This allows it to think that PHI[4, undef] == 4. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@17096 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Utils/Local.cpp | 5 +++-- 1 file changed, 3 insertions(+), 2 deletions(-) diff --git a/lib/Transforms/Utils/Local.cpp b/lib/Transforms/Utils/Local.cpp index fe27f308cf0..b188884a405 100644 --- a/lib/Transforms/Utils/Local.cpp +++ b/lib/Transforms/Utils/Local.cpp @@ -353,7 +353,8 @@ Value *llvm::hasConstantValue(PHINode *PN) { // Value *InVal = 0; for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) - if (PN->getIncomingValue(i) != PN) // Not the PHI node itself... + if (PN->getIncomingValue(i) != PN && // Not the PHI node itself... + !isa(PN->getIncomingValue(i))) if (InVal && PN->getIncomingValue(i) != InVal) return 0; // Not the same, bail out. else @@ -363,7 +364,7 @@ Value *llvm::hasConstantValue(PHINode *PN) { // that only has entries for itself. In this case, there is no entry into the // loop, so kill the PHI. // - if (InVal == 0) InVal = Constant::getNullValue(PN->getType()); + if (InVal == 0) InVal = UndefValue::get(PN->getType()); // All of the incoming values are the same, return the value now. return InVal;