Marcin Hoffmann hoffis
hoffis
/ ipow.c
Created
July 27, 2017 08:53
— forked from orlp/ipow.c
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| int64_t ipow(int64_t base, uint8_t exp) { | |
| static const uint8_t highest_bit_set[] = { | |
| 0, 1, 2, 2, 3, 3, 3, 3, | |
| 4, 4, 4, 4, 4, 4, 4, 4, | |
| 5, 5, 5, 5, 5, 5, 5, 5, | |
| 5, 5, 5, 5, 5, 5, 5, 5, | |
| 6, 6, 6, 6, 6, 6, 6, 6, | |
| 6, 6, 6, 6, 6, 6, 6, 6, | |
| 6, 6, 6, 6, 6, 6, 6, 6, | |
| 6, 6, 6, 6, 6, 6, 6, 255, // anything past 63 is a guaranteed overflow with base > 1 |