Created
March 30, 2012 06:14
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Compact ARM bit count routine
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| /* | |
| * Compact ARM bitcount | |
| * Copyright (c) 2012 Corey Tabaka | |
| */ | |
| #include <asm.h> | |
| .text | |
| .syntax unified | |
| FUNCTION(bitcount) | |
| movs r1, r0 | |
| beq 1f | |
| mov r0, #0 | |
| 0: add r0, r0, #1 | |
| sub r2, r1, #1 | |
| ands r1, r1, r2 | |
| bne 0b | |
| 1: bx lr |
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