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clz emulation
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| static inline int clz(uint32_t input) | |
| { | |
| const uint8_t clz_lut[16] = { 4, 3, 2, 2, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0 }; | |
| unsigned c = 0; | |
| if (input & 0xFFFF0000) | |
| input >>= 16; | |
| else | |
| c = 16; | |
| if (input & 0xFF00) | |
| input >>= 8; | |
| else | |
| c += 8; | |
| if (input & 0xF0) | |
| input >>= 4; | |
| else | |
| c += 4; | |
| return clz_lut[input] + c; | |
| } |
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