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@przemoc
Created July 19, 2010 14:06
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Fibonacci n-th number (modulo 2^32) in x86 assembler
; Fibonacci n-th number (modulo 2^32)
;
; input:
; ecx = n
; modifies:
; eax, ecx, edx
; ouput:
; eax = number
; size:
; 15 bytes
use32
_fibonacci:
xor eax, eax ; 31 c0
jecxz _fibonacci_end ; e3 0a
dec ecx ; 49
inc eax ; 40
jecxz _fibonacci_end ; e3 06
cdq ; 99
_fibonacci_loop:
xchg eax, edx ; 92
add eax, edx ; 01 d0
loop _fibonacci_loop ; e2 fb
_fibonacci_end:
ret ; c3
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przemoc commented Dec 19, 2013

@paulfurber: Thanks for providing FP versions! They're not as short as I would like them to be, though. :>

Anyway, I'm not FP guy myself, so I won't fiddle with squeezing it as much as possible (please forgive my rude assumption that it is possible), but others are free to do so in the comments!

And sorry for late reply, but unfortunately gists lacks any notification system...

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