Checking for "zero operands" during the "CanHoistInst()" method isn't necessary
because those with side effects will be caught by other checks in here.
Also, simplify the check for a BB in a sub loop.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@44871 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/MachineLICM.cpp b/lib/CodeGen/MachineLICM.cpp
index c66e062..b158e90 100644
--- a/lib/CodeGen/MachineLICM.cpp
+++ b/lib/CodeGen/MachineLICM.cpp
@@ -99,13 +99,7 @@
///
bool IsInSubLoop(MachineBasicBlock *BB) {
assert(CurLoop->contains(BB) && "Only valid if BB is IN the loop");
-
- for (MachineLoop::iterator
- I = CurLoop->begin(), E = CurLoop->end(); I != E; ++I)
- if ((*I)->contains(BB))
- return true; // A subloop actually contains this block!
-
- return false;
+ return LI->getLoopFor(BB) != CurLoop;
}
/// CanHoistInst - Checks that this instructions is one that can be hoisted
@@ -115,9 +109,8 @@
bool CanHoistInst(MachineInstr &I) const {
const TargetInstrDescriptor *TID = I.getInstrDescriptor();
- // Don't hoist if this instruction implicitly reads physical registers or
- // doesn't take any operands.
- if (TID->ImplicitUses || !I.getNumOperands()) return false;
+ // Don't hoist if this instruction implicitly reads physical registers.
+ if (TID->ImplicitUses) return false;
MachineOpCode Opcode = TID->Opcode;
return TII->isTriviallyReMaterializable(&I) &&
@@ -142,7 +135,7 @@
/// FindPredecessors - Get all of the predecessors of the loop that are not
/// back-edges.
///
- void FindPredecessors(std::vector<MachineBasicBlock*> &Preds){
+ void FindPredecessors(std::vector<MachineBasicBlock*> &Preds) {
const MachineBasicBlock *Header = CurLoop->getHeader();
for (MachineBasicBlock::const_pred_iterator