Be more precise about verifying missing kill flags.

It is legal for an instruction to have two operands using the same register,
only one a kill. This is interpreted as a kill.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@117981 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 4 insertions, 2 deletions

diff --git a/lib/CodeGen/MachineVerifier.cpp b/lib/CodeGen/MachineVerifier.cpp
index 68688cacab..8ada60a553 100644
--- a/lib/CodeGen/MachineVerifier.cpp
+++ b/lib/CodeGen/MachineVerifier.cpp
@@ -624,12 +624,14 @@ MachineVerifier::visitMachineOperand(const MachineOperand *MO, unsigned MONum) {
           }
           // Verify isKill == LI.killedAt.
           if (!MI->isRegTiedToDefOperand(MONum)) {
+            // MI could kill register without a kill flag on MO.
+            bool miKill = MI->killsRegister(Reg);
             bool liKill = LI.killedAt(UseIdx.getDefIndex());
-            if (isKill && !liKill) {
+            if (miKill && !liKill) {
               report("Live range continues after kill flag", MO, MONum);
               *OS << "Live range: " << LI << '\n';
             }
-            if (!isKill && liKill) {
+            if (!miKill && liKill) {
               report("Live range ends without kill flag", MO, MONum);
               *OS << "Live range: " << LI << '\n';
             }