quad_arg A 64-bit quantity, either in a register or in an aligned quadword memory location. leq_32bits Label to branch to if quad_arg is a 32-bit sign-extended value. gtr_32bits Label to branch to if quad_arg is greater than 32 bits. temp_reg=22 Register to use as a temporary register for holding the low longword of the source value-R22 is the default.