Method DIVOp

FEXCore/Source/Interface/Core/OpcodeDispatcher.cpp:3632–3671

}

void OpDispatchBuilder::DIVOp(OpcodeArgs) {
  const auto GPRSize = GetGPROpSize();
  auto Size = OpSizeFromSrc(Op);

  // This loads the divisor. 32-bit/64-bit paths mask inside the JIT, 8/16 do not.
  Ref Divisor = LoadSource(GPRClass, Op, Op->Dest, Op->Flags, {.AllowUpperGarbage = Size >= OpSize::i32Bit});

  if (Size == OpSize::i64Bit && !Is64BitMode) {
    LogMan::Msg::EFmt("Doesn't exist in 32bit mode");
    DecodeFailure = true;
    return;
  }

  Ref Quotient = _AllocateGPR(true);
  Ref Remainder = _AllocateGPR(true);

  if (Size == OpSize::i8Bit) {
    Ref Src1 = LoadGPRRegister(X86State::REG_RAX, OpSize::i16Bit);

    _UDiv(OpSize::i16Bit, Src1, Invalid(), Divisor, Quotient, Remainder);

    // AX[15:0] = concat<URem[7:0]:UDiv[7:0]>
    auto ResultAX = _Bfi(GPRSize, 8, 8, Quotient, Remainder);
    StoreGPRRegister(X86State::REG_RAX, ResultAX, OpSize::i16Bit);
  } else {
    Ref Src1 = LoadGPRRegister(X86State::REG_RAX);
    Ref Src2 = LoadGPRRegister(X86State::REG_RDX);

    _UDiv(Size, Src1, Src2, Divisor, Quotient, Remainder);

    if (Size == OpSize::i32Bit) {
      Quotient = _Bfe(OpSize::i32Bit, IR::OpSizeAsBits(Size), 0, Quotient);
      Remainder = _Bfe(OpSize::i32Bit, IR::OpSizeAsBits(Size), 0, Remainder);
      Size = OpSize::iInvalid;
    }

    StoreGPRRegister(X86State::REG_RAX, Quotient, Size);
    StoreGPRRegister(X86State::REG_RDX, Remainder, Size);
  }
}

void OpDispatchBuilder::IDIVOp(OpcodeArgs) {
  // This loads the divisor