Random Numbers

[britlion]

Boriel, I know the compiler's pseudorandom number generator is better than the one in the ROM.

Seen this:

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?

If it's smaller, faster or better, you might want to consider

For posterity, an 8 bit result with 32 bit seed that passes diehard test for 32 bit entropy:

Code:

rnd     ld  hl,0xA280   ; xz -> yw
        ld  de,0xC0DE   ; yw -> zt
        ld  (rnd+1),de  ; x = y, z = w
        ld  a,e         ; w = w ^ ( w << 3 )
        add a,a
        add a,a
        add a,a
        xor e
        ld  e,a
        ld  a,h         ; t = x ^ (x << 1)
        add a,a
        xor h
        ld  d,a
        rra             ; t = t ^ (t >> 1) ^ w
        xor d
        xor e
        ld  h,l         ; y = z
        ld  l,a         ; w = t
        ld  (rnd+4),hl
        ret