[RDF] Skip undef uses when calculating kill flags

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@295856 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Target/Hexagon/RDFLiveness.cpp b/lib/Target/Hexagon/RDFLiveness.cpp
index 6710e5083d53dff2c86e9614ec620403e6ffa728..2a2700ee6ac2cd174e9e0c8f6b43877e01143b9c 100644 (file)
--- a/lib/Target/Hexagon/RDFLiveness.cpp
+++ b/lib/Target/Hexagon/RDFLiveness.cpp
@@ -801,7 +801,7 @@ void Liveness::resetKills(MachineBasicBlock *B) {
         Live.reset(*SR);
     }
     for (auto &Op : MI->operands()) {
-      if (!Op.isReg() || !Op.isUse())
+      if (!Op.isReg() || !Op.isUse() || Op.isUndef())
         continue;
       unsigned R = Op.getReg();
       if (!TargetRegisterInfo::isPhysicalRegister(R))