Inserting a created intrinsic function

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I want to create a new instruction (pip it just passes info to the processor) similar to the U-type instruction in RISC-V. However, instead of it being
Opcode, dest, immediate this new instruction is Opcode, src, immediate. I want to insert this new instruction in IR.

So far I have created a new intrinsic function.

include/llvm/IR/IntrinsicsRISCV.td

let TargetPrefix = "riscv" in {
  def int_riscv_pip : DefaultAttrsIntrinsic<
      [], [llvm_i64_ty, llvm_i64_ty],
      [IntrArgMemOnly, IntrSpeculatable]>;                                           
}

Declared my new instruction format in llvm/lib/Target/RISCV/RISCVInstrFormats.td

class RVInstPIP<RISCVOpcode opcode, dag outs, dag ins, string opcodestr,
              string argstr>
    : RVInst<outs, ins, opcodestr, argstr, [], InstFormatPIP> {
  bits<20> imm20;
  bits<5> rs1;

  let Inst{31-12} = imm20;
  let Inst{11-7} = rs1;
  let Opcode = opcode.Value;
}

I have added instruction logic in the llvm/lib/Target/RISCV/RISCVInstrInfo.td

let hasSideEffects = 0, mayLoad = 0, mayStore = 0 in {
def PIP : RVInstPIP< OPC_CUSTOM_1, (outs), (ins  GPR:$rs1, uimm20_lui:$imm20),
                  "pip", "$rs1, $imm20">;
}

However when I try to get my new intrinsic function, it does not even recognize it and I get this error: ‘pip’ is not a member of ‘llvm::Intrinsic’
(not the full pass)

#include "llvm/IR/Intrinsics.h"
static bool safeRegion( Function &F, const TargetLibraryInfo &TLI) 

  for (auto& B : F) {
    for (auto& I : B) {
      if(auto *callInst = dyn_cast<CallInst>(&I)){
          IRBuilder<> builder(callInst);
          Function* new_func = Intrinsic::getDeclaration(F.getParent(), Intrinsic::pip);
      }
    }
  }