MachineBasicBlock::remove should not modify the iterator passed in


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@12571 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/PHIElimination.cpp b/lib/CodeGen/PHIElimination.cpp
index 181fe46..324f4c4 100644
--- a/lib/CodeGen/PHIElimination.cpp
+++ b/lib/CodeGen/PHIElimination.cpp
@@ -71,8 +71,7 @@
 
   while (MBB.front().getOpcode() == TargetInstrInfo::PHI) {
     // Unlink the PHI node from the basic block... but don't delete the PHI yet
-    MachineBasicBlock::iterator begin = MBB.begin();
-    MachineInstr *MI = MBB.remove(begin);
+    MachineInstr *MI = MBB.remove(MBB.begin());
     
     assert(MRegisterInfo::isVirtualRegister(MI->getOperand(0).getReg()) &&
            "PHI node doesn't write virt reg?");