Grab the TargetRegisterInfo off of the subtarget from the
MachineFunction rather than a lookup on the TargetMachine
to avoid unnecessary lookups.

llvm-svn: 219291
diff --git a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
index 628ea62..006f3e0 100644
--- a/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
+++ b/llvm/lib/CodeGen/SelectionDAG/SelectionDAGISel.cpp
@@ -454,7 +454,7 @@
   // copied into vregs, emit the copies into the top of the block before
   // emitting the code for the block.
   MachineBasicBlock *EntryMBB = MF->begin();
-  const TargetRegisterInfo &TRI = *TM.getSubtargetImpl()->getRegisterInfo();
+  const TargetRegisterInfo &TRI = *MF->getSubtarget().getRegisterInfo();
   RegInfo->EmitLiveInCopies(EntryMBB, TRI, *TII);
 
   DenseMap<unsigned, unsigned> LiveInMap;