diff options
Diffstat (limited to 'src/base/bitfield.hh')
-rw-r--r-- | src/base/bitfield.hh | 25 |
1 files changed, 25 insertions, 0 deletions
diff --git a/src/base/bitfield.hh b/src/base/bitfield.hh index 0f1233677..83b9138b4 100644 --- a/src/base/bitfield.hh +++ b/src/base/bitfield.hh @@ -112,4 +112,29 @@ replaceBits(T& val, int first, int last, B bit_val) val = insertBits(val, first, last, bit_val); } +/** + * Returns the bit position of the MSB that is set in the input + */ +inline +int +findMsbSet(uint64_t val) { + int msb = 0; + if (!val) + return 0; + if (bits(val, 63,32)) msb += 32; + val >>= 32; + if (bits(val, 31,16)) msb += 16; + val >>= 16; + if (bits(val, 15,8)) msb += 8; + val >>= 8; + if (bits(val, 7,4)) msb += 4; + val >>= 4; + if (bits(val, 3,2)) msb += 2; + val >>= 2; + if (bits(val, 1,1)) msb += 1; + return msb; +} + + + #endif // __BASE_BITFIELD_HH__ |