Remove dead function AArch64TargetLowering::getFunctionAlignment. NFC.

[mcrosier]

Seems straight forward to me..

llvm/trunk/lib/Target/AArch64/AArch64ISelLowering.h

public:
 
   /// Provide custom lowering hooks for some operations.
   SDValue LowerOperation(SDValue Op, SelectionDAG &DAG) const override;
 
   const char *getTargetNodeName(unsigned Opcode) const override;
 
   SDValue PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const override;
 
-  /// Return the Log2 alignment of this function.
-  unsigned getFunctionAlignment(const Function *F) const;
-
   /// Returns true if a cast between SrcAS and DestAS is a noop.
   bool isNoopAddrSpaceCast(unsigned SrcAS, unsigned DestAS) const override {
     // Addrspacecasts are always noops.
     return true;
   }
 
   /// This method returns a target specific FastISel object, or null if the
   /// target does not support "fast" ISel.

llvm/trunk/lib/Target/AArch64/AArch64ISelLowering.cpp

case ISD::FSINCOS:
     return LowerFSINCOS(Op, DAG);
   case ISD::MUL:
     return LowerMUL(Op, DAG);
   case ISD::INTRINSIC_WO_CHAIN:
     return LowerINTRINSIC_WO_CHAIN(Op, DAG);
   }
 }
 
-/// getFunctionAlignment - Return the Log2 alignment of this function.
-unsigned AArch64TargetLowering::getFunctionAlignment(const Function *F) const {
-  return 2;
-}
-
 //===----------------------------------------------------------------------===//
 //                      Calling Convention Implementation
 //===----------------------------------------------------------------------===//
 
 #include "AArch64GenCallingConv.inc"
 
 /// Selects the correct CCAssignFn for a given CallingConvention value.
 CCAssignFn *AArch64TargetLowering::CCAssignFnForCall(CallingConv::ID CC,