When LiveVariables is adding implicit-def to model "partial dead", add the earlyclobber marker if the superreg def has it.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@84153 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/LiveVariables.cpp b/lib/CodeGen/LiveVariables.cpp
index 139e029..96c655c 100644
--- a/lib/CodeGen/LiveVariables.cpp
+++ b/lib/CodeGen/LiveVariables.cpp
@@ -323,10 +323,21 @@
// The last partial def kills the register.
LastPartDef->addOperand(MachineOperand::CreateReg(Reg, false/*IsDef*/,
true/*IsImp*/, true/*IsKill*/));
- else
+ else {
+ MachineOperand *MO =
+ LastRefOrPartRef->findRegisterDefOperand(Reg, false, TRI);
+ bool NeedEC = MO->isEarlyClobber() && MO->getReg() != Reg;
// If the last reference is the last def, then it's not used at all.
// That is, unless we are currently processing the last reference itself.
LastRefOrPartRef->addRegisterDead(Reg, TRI, true);
+ if (NeedEC) {
+ // If we are adding a subreg def and the superreg def is marked early
+ // clobber, add an early clobber marker to the subreg def.
+ MO = LastRefOrPartRef->findRegisterDefOperand(Reg);
+ if (MO)
+ MO->setIsEarlyClobber();
+ }
+ }
} else if (!PhysRegUse[Reg]) {
// Partial uses. Mark register def dead and add implicit def of
// sub-registers which are used.