Mercurial > hg > openttd
changeset 11241:3b5cf99c0f67 draft bitmath
-Codechange: Use builtins with MSVC for bitmath functions.
| author | Michael Lutz <michi@icosahedron.de> |
|---|---|
| date | Wed, 03 Sep 2008 15:29:45 +0200 |
| parents | 320cc407142b |
| children | |
| files | src/core/bitmath_func.cpp src/core/bitmath_func.hpp |
| diffstat | 2 files changed, 53 insertions(+), 1 deletions(-) [+] |
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--- a/src/core/bitmath_func.cpp +++ b/src/core/bitmath_func.cpp @@ -16,6 +16,7 @@ 3, 0, 1, 0, 2, 0, 1, 0, }; +#if !defined(_MSC_VER) || _MSC_VER < 1300 /** * Search the first set bit in a 32 bit variable. * @@ -43,7 +44,9 @@ return pos; } +#endif +#if !defined(_MSC_VER) || _MSC_VER < 1300 || (!defined(_M_AMD64) && !defined(_M_IA64)) /** * Search the last set bit in a 64 bit variable. * @@ -70,3 +73,4 @@ return pos; } +#endif
--- a/src/core/bitmath_func.hpp +++ b/src/core/bitmath_func.hpp @@ -220,6 +220,28 @@ uint8 FindFirstBit(uint32 x); uint8 FindLastBit(uint64 x); +#if defined(_MSC_VER) && _MSC_VER >= 1300 +/* MSVC has intrinsics for finding the first/last bit. */ +#include <intrin.h> +#pragma intrinsic(_BitScanForward) + +inline uint8 FindFirstBit(uint32 x) +{ + unsigned long index; + return _BitScanForward(&index, x) ? index : 0; +} + +#if defined(_M_AMD64) || defined(_M_IA64) +#pragma intrinsic(_BitScanReverse64) +inline uint8 FindLastBit(uint64 x) +{ + unsigned long index; + return _BitScanReverse64(&index, x) ? index : 0; +} +#endif /* defined(_M_AMD64) || defined(_M_IA64) */ + +#endif /* defined(_MSC_VER) && _MSC_VER >= 1300 */ + /** * Clear the first bit in an integer. * @@ -273,6 +295,16 @@ return (T)(x << n | x >> (sizeof(x) * 8 - n)); } +#if defined(_MSC_VER) && _MSC_VER >= 1300 +#pragma intrinsic(_rotl) +/* Use the MSVC intrinsic to speed up the code. */ +template <> +static FORCEINLINE uint32 ROL(const uint32 x, const uint8 n) +{ + return _rotl(x, n); +} +#endif + /** * ROtate x Right by n * @@ -287,6 +319,16 @@ return (T)(x >> n | x << (sizeof(x) * 8 - n)); } +#if defined(_MSC_VER) && _MSC_VER >= 1300 +#pragma intrinsic(_rotr) +/* Use the MSVC intrinsic to speed up the code. */ +template <> +static FORCEINLINE uint32 ROR(const uint32 x, const uint8 n) +{ + return _rotr(x, n); +} +#endif + /** * Do an operation for each set set bit in a value. * @@ -310,6 +352,12 @@ * warnings if we don't cast those (why?) */ #define BSWAP32(x) ((uint32)Endian32_Swap(x)) #define BSWAP16(x) ((uint16)Endian16_Swap(x)) +#elif defined(_MSC_VER) && _MSC_VER >= 1300 + #pragma intrinsic(_byteswap_ulong) + #pragma intrinsic(_byteswap_ushort) + /* Use the MSVC intrinsics to speed up the code. */ + #define BSWAP32(x) ((uint32)_byteswap_ulong(x)) + #define BSWAP16(x) ((uint16)_byteswap_ushort(x)) #else /** * Perform a 32 bits endianness bitswap on x. @@ -335,6 +383,6 @@ { return (x >> 8) | (x << 8); } -#endif /* __APPLE__ */ +#endif #endif /* BITMATH_FUNC_HPP */