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@remexre
Created November 1, 2018 05:20
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Miscellaneous assembly snippets
bits 64
global dehex
[section .text]
; unsigned char dehex(const char hex[2]);
dehex:
mov ax, [rdi]
sub ax, 12336
cmp ax, 2559
jl .L1
sub ax, 1792
.L1:
cmp al, 9
jle .L2
sub al, 7
.L2:
xchg ah, al
shl ah, 4
or al, ah
ret
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