bpf: Use the getSubtarget call off of the MachineFunction rather than the TargetMachine

[ast]

Summary

Hi Eric,

this patch cleans up the layering violation that you're fixing across backends.
Anything else I need to fix on bpf backend side?

Thanks

[echristo]

Thanks! I don't see anything else on a quick glance through the backend.

-eric

llvm/trunk/lib/Target/BPF/BPFISelLowering.cpp

SDValue BPFTargetLowering::LowerGlobalAddress(SDValue Op,
   return DAG.getNode(BPFISD::Wrapper, DL, MVT::i64, GA);
 }
 
 MachineBasicBlock *
 BPFTargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
                                                MachineBasicBlock *BB) const {
   unsigned Opc = MI->getOpcode();
 
-  const TargetInstrInfo &TII =
-      *getTargetMachine().getSubtargetImpl()->getInstrInfo();
+  const TargetInstrInfo &TII = *BB->getParent()->getSubtarget().getInstrInfo();
   DebugLoc DL = MI->getDebugLoc();
 
   assert(Opc == BPF::Select && "Unexpected instr type to insert");
 
   // To "insert" a SELECT instruction, we actually have to insert the diamond
   // control-flow pattern.  The incoming instruction knows the destination vreg
   // to set, the condition code register to branch on, the true/false values to
   // select between, and a branch opcode to use.