Use AllocationOrder in RegAllocGreedy, fix a bug in the hint calculation.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@121584 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/CodeGen/AllocationOrder.cpp b/lib/CodeGen/AllocationOrder.cpp
index 3f08439..26d4cd4 100644
--- a/lib/CodeGen/AllocationOrder.cpp
+++ b/lib/CodeGen/AllocationOrder.cpp
@@ -36,6 +36,10 @@
   if (Hint && TargetRegisterInfo::isVirtualRegister(Hint))
     Hint = VRM.getPhys(Hint);
 
+  // The remaining allocation order may depend on the hint.
+  tie(Begin, End) = VRM.getTargetRegInfo()
+        .getAllocationOrder(RC, HintPair.first, Hint, VRM.getMachineFunction());
+
   // Target-dependent hints require resolution.
   if (HintPair.first)
     Hint = VRM.getTargetRegInfo().ResolveRegAllocHint(HintPair.first, Hint,
@@ -45,10 +49,6 @@
   if (Hint && (!TargetRegisterInfo::isPhysicalRegister(Hint) ||
                !RC->contains(Hint) || ReservedRegs.test(Hint)))
     Hint = 0;
-
-  // The remaining allocation order may also depend on the hint.
-  tie(Begin, End) = VRM.getTargetRegInfo()
-        .getAllocationOrder(RC, HintPair.first, Hint, VRM.getMachineFunction());
 }
 
 unsigned AllocationOrder::next() {