diff options
Diffstat (limited to 'deps/jemalloc/include/msvc_compat/strings.h')
-rw-r--r-- | deps/jemalloc/include/msvc_compat/strings.h | 58 |
1 files changed, 58 insertions, 0 deletions
diff --git a/deps/jemalloc/include/msvc_compat/strings.h b/deps/jemalloc/include/msvc_compat/strings.h new file mode 100644 index 0000000..996f256 --- /dev/null +++ b/deps/jemalloc/include/msvc_compat/strings.h @@ -0,0 +1,58 @@ +#ifndef strings_h +#define strings_h + +/* MSVC doesn't define ffs/ffsl. This dummy strings.h header is provided + * for both */ +#ifdef _MSC_VER +# include <intrin.h> +# pragma intrinsic(_BitScanForward) +static __forceinline int ffsl(long x) { + unsigned long i; + + if (_BitScanForward(&i, x)) { + return i + 1; + } + return 0; +} + +static __forceinline int ffs(int x) { + return ffsl(x); +} + +# ifdef _M_X64 +# pragma intrinsic(_BitScanForward64) +# endif + +static __forceinline int ffsll(unsigned __int64 x) { + unsigned long i; +#ifdef _M_X64 + if (_BitScanForward64(&i, x)) { + return i + 1; + } + return 0; +#else +// Fallback for 32-bit build where 64-bit version not available +// assuming little endian + union { + unsigned __int64 ll; + unsigned long l[2]; + } s; + + s.ll = x; + + if (_BitScanForward(&i, s.l[0])) { + return i + 1; + } else if(_BitScanForward(&i, s.l[1])) { + return i + 33; + } + return 0; +#endif +} + +#else +# define ffsll(x) __builtin_ffsll(x) +# define ffsl(x) __builtin_ffsl(x) +# define ffs(x) __builtin_ffs(x) +#endif + +#endif /* strings_h */ |