PRNG - routine

gistfile1.asm

PrngGet PROC range:DWORD

        ; count the number of cycles since
        ; the machine has been reset
        rdtsc

        ; accumulate the value in eax and manage
        ; any carry-spill into the x state var
        adc eax, edx
        adc eax, prng_x

        ; multiply this calculation by the seed
        mul prng_a

        ; manage the spill into the x state var
        adc eax, edx
        mov prng_x, eax

        ; put the calculation in range of what
        ; was requested
        mul range

        ; ranged-random value in eax
        mov eax, edx

        ret

PrngGet ENDP