Fast path implicit_def check.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@101183 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineLICM.cpp b/lib/CodeGen/MachineLICM.cpp
index 13a4b85..7f530ac 100644
--- a/lib/CodeGen/MachineLICM.cpp
+++ b/lib/CodeGen/MachineLICM.cpp
@@ -300,7 +300,7 @@
"Not expecting virtual register!");
if (!MO.isDef()) {
- if (PhysRegDefs[Reg])
+ if (Reg && PhysRegDefs[Reg])
// If it's using a non-loop-invariant register, then it's obviously not
// safe to hoist.
HasNonInvariantUse = true;
@@ -406,7 +406,7 @@
MachineInstr *MI = Candidates[i].MI;
for (unsigned j = 0, ee = MI->getNumOperands(); j != ee; ++j) {
const MachineOperand &MO = MI->getOperand(j);
- if (!MO.isReg() || MO.isDef())
+ if (!MO.isReg() || MO.isDef() || !MO.getReg())
continue;
if (PhysRegDefs[MO.getReg()]) {
// If it's using a non-loop-invariant register, then it's obviously
@@ -502,6 +502,9 @@
/// candidate for LICM. e.g. If the instruction is a call, then it's obviously
/// not safe to hoist it.
bool MachineLICM::IsLICMCandidate(MachineInstr &I) {
+ if (I.isImplicitDef())
+ return false;
+
const TargetInstrDesc &TID = I.getDesc();
// Ignore stuff that we obviously can't hoist.
@@ -620,9 +623,6 @@
/// IsProfitableToHoist - Return true if it is potentially profitable to hoist
/// the given loop invariant.
bool MachineLICM::IsProfitableToHoist(MachineInstr &MI) {
- if (MI.isImplicitDef())
- return false;
-
// FIXME: For now, only hoist re-materilizable instructions. LICM will
// increase register pressure. We want to make sure it doesn't increase
// spilling.