diff options
Diffstat (limited to 'src/core/bitmath_func.cpp')
| -rw-r--r-- | src/core/bitmath_func.cpp | 15 |
1 files changed, 8 insertions, 7 deletions
diff --git a/src/core/bitmath_func.cpp b/src/core/bitmath_func.cpp index bbfad72ff..614caa53f 100644 --- a/src/core/bitmath_func.cpp +++ b/src/core/bitmath_func.cpp @@ -45,7 +45,7 @@ uint8 FindFirstBit(uint32 x) } /** - * Search the last set bit in a 32 bit variable. + * Search the last set bit in a 64 bit variable. * * This algorithm is a static implementation of a log * conguence search algorithm. It checks the second half @@ -55,17 +55,18 @@ uint8 FindFirstBit(uint32 x) * @param x The value to search * @return The position of the last bit set */ -uint8 FindLastBit(uint32 x) +uint8 FindLastBit(uint64 x) { if (x == 0) return 0; uint8 pos = 0; - if ((x & 0xffff0000) != 0) { x >>= 16; pos += 16; } - if ((x & 0x0000ff00) != 0) { x >>= 8; pos += 8; } - if ((x & 0x000000f0) != 0) { x >>= 4; pos += 4; } - if ((x & 0x0000000c) != 0) { x >>= 2; pos += 2; } - if ((x & 0x00000002) != 0) { pos += 1; } + if ((x & 0xffffffff00000000ULL) != 0) { x >>= 32; pos += 32; } + if ((x & 0x00000000ffff0000ULL) != 0) { x >>= 16; pos += 16; } + if ((x & 0x000000000000ff00ULL) != 0) { x >>= 8; pos += 8; } + if ((x & 0x00000000000000f0ULL) != 0) { x >>= 4; pos += 4; } + if ((x & 0x000000000000000cULL) != 0) { x >>= 2; pos += 2; } + if ((x & 0x0000000000000002ULL) != 0) { pos += 1; } return pos; } |