Use MCPhysReg for RegisterClassInfo allocation orders.

This saves a bit of memory.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@168852 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/CriticalAntiDepBreaker.cpp b/lib/CodeGen/CriticalAntiDepBreaker.cpp
index 377b471..f2bf938 100644
--- a/lib/CodeGen/CriticalAntiDepBreaker.cpp
+++ b/lib/CodeGen/CriticalAntiDepBreaker.cpp
@@ -378,7 +378,7 @@
                                                  unsigned LastNewReg,
                                                  const TargetRegisterClass *RC)
 {
-  ArrayRef<unsigned> Order = RegClassInfo.getOrder(RC);
+  ArrayRef<MCPhysReg> Order = RegClassInfo.getOrder(RC);
   for (unsigned i = 0; i != Order.size(); ++i) {
     unsigned NewReg = Order[i];
     // Don't replace a register with itself.