- Check if a register is livein before removing it. It may have already been removed.

- Do not iterate over SmallPtrSet, the order of iteration is not deterministic.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50209 91177308-0d34-0410-b5e6-96231b3b80d8

lib/CodeGen/MachineBasicBlock.cpp

@@ -205,6 +205,11 @@ void MachineBasicBlock::removeLiveIn(unsigned Reg) {
   LiveIns.erase(I);
 }
 
+bool MachineBasicBlock::isLiveIn(unsigned Reg) const {
+  const_livein_iterator I = std::find(livein_begin(), livein_end(), Reg);
+  return I != livein_end();
+}
+
 void MachineBasicBlock::moveBefore(MachineBasicBlock *NewAfter) {
   MachineFunction::BasicBlockListType &BBList =getParent()->getBasicBlockList();
   getParent()->getBasicBlockList().splice(NewAfter, BBList, this);