Don't pull a load through a callseq_start if the load's chain
has multiple uses, as one of the other uses may be on a path
to a different node above the callseq_start, because that
leads to a cyclic graph. This problem is exposed when
-combiner-global-alias-analysis is used. This fixes PR4880.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@81821 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp
index 22d676e..a900a69 100644
--- a/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -447,7 +447,8 @@
if (Chain.getOperand(0).getNode() == Callee.getNode())
return true;
if (Chain.getOperand(0).getOpcode() == ISD::TokenFactor &&
- Callee.getValue(1).isOperandOf(Chain.getOperand(0).getNode()))
+ Callee.getValue(1).isOperandOf(Chain.getOperand(0).getNode()) &&
+ Callee.getValue(1).hasOneUse())
return true;
return false;
}