Allow missing kill flags on an untied operand of a two-address instruction when
the operand uses the same register as a tied operand:
%r1 = add %r1, %r1
If add were a three-address instruction, kill flags would be required on at
least one of the uses. Since it is a two-address instruction, the tied use
operand must not have a kill flag.
This change makes the kill flag on the untied use operand optional.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@122082 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineVerifier.cpp b/lib/CodeGen/MachineVerifier.cpp
index f92b7fe..1e2b478 100644
--- a/lib/CodeGen/MachineVerifier.cpp
+++ b/lib/CodeGen/MachineVerifier.cpp
@@ -625,7 +625,12 @@
*OS << UseIdx << " is not live in " << LI << '\n';
}
// Verify isKill == LI.killedAt.
- if (!MI->isRegTiedToDefOperand(MONum)) {
+ // Two-address instrs don't have kill flags on the tied operands, and
+ // we even allow
+ // %r1 = add %r1, %r1
+ // without a kill flag on the untied operand.
+ // MI->findRegisterUseOperandIdx finds the first operand using reg.
+ if (!MI->isRegTiedToDefOperand(MI->findRegisterUseOperandIdx(Reg))) {
// MI could kill register without a kill flag on MO.
bool miKill = MI->killsRegister(Reg);
bool liKill = LI.killedAt(UseIdx.getDefIndex());