Created
November 1, 2018 05:20
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Miscellaneous assembly snippets
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| 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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