diff options
Diffstat (limited to 'lib/CodeGen/RegisterScavenging.cpp')
-rw-r--r-- | lib/CodeGen/RegisterScavenging.cpp | 5 |
1 files changed, 4 insertions, 1 deletions
diff --git a/lib/CodeGen/RegisterScavenging.cpp b/lib/CodeGen/RegisterScavenging.cpp index ebfe533838..e2c25aba02 100644 --- a/lib/CodeGen/RegisterScavenging.cpp +++ b/lib/CodeGen/RegisterScavenging.cpp @@ -154,13 +154,16 @@ void RegScavenger::forward() { BitVector DeadRegs(NumPhysRegs); for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { const MachineOperand &MO = MI->getOperand(i); - if (!MO.isReg() || MO.isUndef()) + if (!MO.isReg()) continue; unsigned Reg = MO.getReg(); if (!Reg || isReserved(Reg)) continue; if (MO.isUse()) { + // Ignore undef uses. + if (MO.isUndef()) + continue; // Two-address operands implicitly kill. if (!isPred && (MO.isKill() || MI->isRegTiedToDefOperand(i))) addRegWithSubRegs(KillRegs, Reg); |