// requires special handling.
func IsRISCV64VTypeI(op obj.As) bool {
	return op == riscv.AVSETVLI || op == riscv.AVSETIVLI
}

// IsRISCV64CSRO reports whether the op is an instruction that uses
// CSR symbolic names and whether that instruction expects a register
// or an immediate source operand.
func IsRISCV64CSRO(op obj.As) (imm bool, ok bool) {
	switch op {
	case riscv.ACSRRCI, riscv.ACSRRSI, riscv.ACSRRWI:
		imm = true
		fallthrough

					return
				}
				prog.RegTo2 = a[2].Reg
				break
			}
			// RISCV64 instructions that reference CSRs with symbolic names.
			if isImm, ok := arch.IsRISCV64CSRO(op); ok {
				if a[0].Type != obj.TYPE_CONST && isImm {
					p.errorf("invalid value for first operand to %s instruction, must be a 5 bit unsigned immediate", op)
					return
				}