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| author | rubidium <rubidium@openttd.org> | 2007-12-10 22:26:24 +0000 |
|---|---|---|
| committer | rubidium <rubidium@openttd.org> | 2007-12-10 22:26:24 +0000 |
| commit | a1dbb10c26763574d7cdd66d0e9522382164a773 (patch) | |
| tree | c567c5687d1d60dfa3feffb7d149f848ed838bf2 /src/core | |
| parent | ac7c79f039f43aed145c327b06ea9edadfbbe7f3 (diff) | |
| download | openttd-a1dbb10c26763574d7cdd66d0e9522382164a773.tar.xz | |
(svn r11616) -Fix [FS#1526]: sometimes large values could go off the chart.
Diffstat (limited to 'src/core')
| -rw-r--r-- | src/core/bitmath_func.cpp | 15 | ||||
| -rw-r--r-- | src/core/bitmath_func.hpp | 2 |
2 files changed, 9 insertions, 8 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; } diff --git a/src/core/bitmath_func.hpp b/src/core/bitmath_func.hpp index f4c6ff0bc..357a52212 100644 --- a/src/core/bitmath_func.hpp +++ b/src/core/bitmath_func.hpp @@ -211,7 +211,7 @@ static inline uint8 FindFirstBit2x64(const int value) } uint8 FindFirstBit(uint32 x); -uint8 FindLastBit(uint32 x); +uint8 FindLastBit(uint64 x); /** * Clear the first bit in an integer. |