[RISCV] Remove unnecesary override of getVectorTypeBreakdownForCallingConv. NFC (#171155)

There used to be code in here to make i32 legal on RV64, but it was
removed.

Also remove unnecessary temporary variable from
getRegisterTypeForCallingConv.

Author: topperc

llvm/lib/Target/RISCV/RISCVISelLowering.cpp

@@ -2581,9 +2581,7 @@ MVT RISCVTargetLowering::getRegisterTypeForCallingConv(LLVMContext &Context,
       !Subtarget.hasStdExtZfhminOrZhinxmin())
     return MVT::f32;
 
-  MVT PartVT = TargetLowering::getRegisterTypeForCallingConv(Context, CC, VT);
-
-  return PartVT;
+  return TargetLowering::getRegisterTypeForCallingConv(Context, CC, VT);
 }
 
 unsigned
@@ -2609,15 +2607,6 @@ unsigned RISCVTargetLowering::getNumRegistersForCallingConv(LLVMContext &Context
   return TargetLowering::getNumRegistersForCallingConv(Context, CC, VT);
 }
 
-unsigned RISCVTargetLowering::getVectorTypeBreakdownForCallingConv(
-    LLVMContext &Context, CallingConv::ID CC, EVT VT, EVT &IntermediateVT,
-    unsigned &NumIntermediates, MVT &RegisterVT) const {
-  unsigned NumRegs = TargetLowering::getVectorTypeBreakdownForCallingConv(
-      Context, CC, VT, IntermediateVT, NumIntermediates, RegisterVT);
-
-  return NumRegs;
-}
-
 // Changes the condition code and swaps operands if necessary, so the SetCC
 // operation matches one of the comparisons supported directly by branches
 // in the RISC-V ISA. May adjust compares to favor compare with 0 over compare

llvm/lib/Target/RISCV/RISCVISelLowering.h

@@ -92,12 +92,6 @@ class RISCVTargetLowering : public TargetLowering {
                                          CallingConv::ID CC,
                                          EVT VT) const override;
 
-  unsigned getVectorTypeBreakdownForCallingConv(LLVMContext &Context,
-                                                CallingConv::ID CC, EVT VT,
-                                                EVT &IntermediateVT,
-                                                unsigned &NumIntermediates,
-                                                MVT &RegisterVT) const override;
-
   bool shouldFoldSelectWithIdentityConstant(unsigned BinOpcode, EVT VT,
                                             unsigned SelectOpcode, SDValue X,
                                             SDValue Y) const override;