Verify kill flags conservatively.
Allow a live range to end with a kill flag, but don't allow a kill flag that
doesn't end the live range.
This makes the machine code verifier more useful during register allocation when
kill flag computation is deferred.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@124838 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineVerifier.cpp b/lib/CodeGen/MachineVerifier.cpp
index ad93f9c..7351119 100644
--- a/lib/CodeGen/MachineVerifier.cpp
+++ b/lib/CodeGen/MachineVerifier.cpp
@@ -647,24 +647,11 @@
report("No live range at use", MO, MONum);
*OS << UseIdx << " is not live in " << LI << '\n';
}
- // Verify isKill == LI.killedAt.
- // 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());
- if (miKill && !liKill) {
- report("Live range continues after kill flag", MO, MONum);
- *OS << "Live range: " << LI << '\n';
- }
- if (!miKill && liKill) {
- report("Live range ends without kill flag", MO, MONum);
- *OS << "Live range: " << LI << '\n';
- }
+ // Check for extra kill flags.
+ // Note that we allow missing kill flags for now.
+ if (MO->isKill() && !LI.killedAt(UseIdx.getDefIndex())) {
+ report("Live range continues after kill flag", MO, MONum);
+ *OS << "Live range: " << LI << '\n';
}
} else {
report("Virtual register has no Live interval", MO, MONum);