[RISCV] Remove unused code

llvm/lib/Target/RISCV/RISCVInstrInfo.td

 }
 
 // Standalone (codegen-only) immleaf patterns.
 
 // A 12-bit signed immediate plus one where the imm range will be [-2047, 2048].
 def simm12_plus1 : ImmLeaf<XLenVT,
   [{return (isInt<12>(Imm) && Imm != -2048) || Imm == 2048;}]>;
 
-// A 12-bit signed immediate sub one and exclude zero
-def simm12_minus1_nonzero : PatLeaf<(imm), [{
-  if (!N->hasOneUse())
-    return false;
-  // The immediate operand must be in range [-2049, 0) or (0, 2046].
-  int64_t Imm = N->getSExtValue();
-  return (Imm >= -2049 && Imm < 0) || (Imm > 0 && Imm <= 2046);
-}]>;
-
 // A 6-bit constant greater than 32.
 def uimm6gt32 : ImmLeaf<XLenVT, [{
   return isUInt<6>(Imm) && Imm > 32;
 }]>;
 
 // Addressing modes.
 // Necessary because a frameindex can't be matched directly in a pattern.
 def FrameAddrRegImm : ComplexPattern<iPTR, 2, "SelectFrameAddrRegImm",
                                      [frameindex, or, add]>;
 def AddrRegImm : ComplexPattern<iPTR, 2, "SelectAddrRegImm">;
 
 // Return the negation of an immediate value.
 def NegImm : SDNodeXForm<imm, [{
   return CurDAG->getTargetConstant(-N->getSExtValue(), SDLoc(N),
                                    N->getValueType(0));
 }]>;
 
 // Return an immediate value minus 32.
 def ImmSub32 : SDNodeXForm<imm, [{
   return CurDAG->getTargetConstant(N->getSExtValue() - 32, SDLoc(N),
                                    N->getValueType(0));
 }]>;
 
-// Return an immediate value plus 1.
-def ImmPlus1 : SDNodeXForm<imm, [{
-  return CurDAG->getTargetConstant(N->getSExtValue() + 1, SDLoc(N),
-                                   N->getValueType(0));
-}]>;
-
 // Return an immediate subtracted from XLen.
 def ImmSubFromXLen : SDNodeXForm<imm, [{
   uint64_t XLen = Subtarget->getXLen();
   return CurDAG->getTargetConstant(XLen - N->getZExtValue(), SDLoc(N),
                                    N->getValueType(0));
 }]>;
 
 // Return an immediate subtracted from 32.