third_party/ulib/jemalloc/include/jemalloc/internal/util_inlines.h

#ifndef JEMALLOC_INTERNAL_UTIL_INLINES_H
#define JEMALLOC_INTERNAL_UTIL_INLINES_H

#ifndef JEMALLOC_ENABLE_INLINE
unsigned	ffs_llu(unsigned long long bitmap);
unsigned	ffs_lu(unsigned long bitmap);
unsigned	ffs_u(unsigned bitmap);
unsigned	ffs_zu(size_t bitmap);
unsigned	ffs_u64(uint64_t bitmap);
unsigned	ffs_u32(uint32_t bitmap);
uint64_t	pow2_ceil_u64(uint64_t x);
uint32_t	pow2_ceil_u32(uint32_t x);
size_t	pow2_ceil_zu(size_t x);
unsigned	lg_floor(size_t x);
void	set_errno(int errnum);
int	get_errno(void);
#endif

#if (defined(JEMALLOC_ENABLE_INLINE) || defined(JEMALLOC_UTIL_C_))

/* Sanity check. */
#if !defined(JEMALLOC_INTERNAL_FFSLL) || !defined(JEMALLOC_INTERNAL_FFSL) \
    || !defined(JEMALLOC_INTERNAL_FFS)
#  error JEMALLOC_INTERNAL_FFS{,L,LL} should have been defined by configure
#endif

JEMALLOC_ALWAYS_INLINE unsigned
ffs_llu(unsigned long long bitmap)
{
	return (JEMALLOC_INTERNAL_FFSLL(bitmap));
}

JEMALLOC_ALWAYS_INLINE unsigned
ffs_lu(unsigned long bitmap)
{
	return (JEMALLOC_INTERNAL_FFSL(bitmap));
}

JEMALLOC_ALWAYS_INLINE unsigned
ffs_u(unsigned bitmap)
{
	return (JEMALLOC_INTERNAL_FFS(bitmap));
}

JEMALLOC_ALWAYS_INLINE unsigned
ffs_zu(size_t bitmap)
{
#if LG_SIZEOF_PTR == LG_SIZEOF_INT
	return (ffs_u(bitmap));
#elif LG_SIZEOF_PTR == LG_SIZEOF_LONG
	return (ffs_lu(bitmap));
#elif LG_SIZEOF_PTR == LG_SIZEOF_LONG_LONG
	return (ffs_llu(bitmap));
#else
#error No implementation for size_t ffs()
#endif
}

JEMALLOC_ALWAYS_INLINE unsigned
ffs_u64(uint64_t bitmap)
{
#if LG_SIZEOF_LONG == 3
	return (ffs_lu(bitmap));
#elif LG_SIZEOF_LONG_LONG == 3
	return (ffs_llu(bitmap));
#else
#error No implementation for 64-bit ffs()
#endif
}

JEMALLOC_ALWAYS_INLINE unsigned
ffs_u32(uint32_t bitmap)
{
#if LG_SIZEOF_INT == 2
	return (ffs_u(bitmap));
#else
#error No implementation for 32-bit ffs()
#endif
	return (ffs_u(bitmap));
}

JEMALLOC_INLINE uint64_t
pow2_ceil_u64(uint64_t x)
{
	x--;
	x |= x >> 1;
	x |= x >> 2;
	x |= x >> 4;
	x |= x >> 8;
	x |= x >> 16;
	x |= x >> 32;
	x++;
	return (x);
}

JEMALLOC_INLINE uint32_t
pow2_ceil_u32(uint32_t x)
{
	x--;
	x |= x >> 1;
	x |= x >> 2;
	x |= x >> 4;
	x |= x >> 8;
	x |= x >> 16;
	x++;
	return (x);
}

/* Compute the smallest power of 2 that is >= x. */
JEMALLOC_INLINE size_t
pow2_ceil_zu(size_t x)
{
#if (LG_SIZEOF_PTR == 3)
	return (pow2_ceil_u64(x));
#else
	return (pow2_ceil_u32(x));
#endif
}

#if (defined(__i386__) || defined(__amd64__) || defined(__x86_64__))
JEMALLOC_INLINE unsigned
lg_floor(size_t x)
{
	size_t ret;

	assert(x != 0);

	__asm__ ("bsr %1, %0"
		: "=r"(ret) // Outputs.
		: "r"(x)    // Inputs.
		);
	assert(ret < UINT_MAX);
	return ((unsigned)ret);
}
#elif (defined(_MSC_VER))
JEMALLOC_INLINE unsigned
lg_floor(size_t x)
{
	unsigned long ret;

	assert(x != 0);

#if (LG_SIZEOF_PTR == 3)
	_BitScanReverse64(&ret, x);
#elif (LG_SIZEOF_PTR == 2)
	_BitScanReverse(&ret, x);
#else
#  error "Unsupported type size for lg_floor()"
#endif
	assert(ret < UINT_MAX);
	return ((unsigned)ret);
}
#elif (defined(JEMALLOC_HAVE_BUILTIN_CLZ))
JEMALLOC_INLINE unsigned
lg_floor(size_t x)
{
	assert(x != 0);

#if (LG_SIZEOF_PTR == LG_SIZEOF_INT)
	return (((8 << LG_SIZEOF_PTR) - 1) - __builtin_clz(x));
#elif (LG_SIZEOF_PTR == LG_SIZEOF_LONG)
	return (((8 << LG_SIZEOF_PTR) - 1) - __builtin_clzl(x));
#else
#  error "Unsupported type size for lg_floor()"
#endif
}
#else
JEMALLOC_INLINE unsigned
lg_floor(size_t x)
{
	assert(x != 0);

	x |= (x >> 1);
	x |= (x >> 2);
	x |= (x >> 4);
	x |= (x >> 8);
	x |= (x >> 16);
#if (LG_SIZEOF_PTR == 3)
	x |= (x >> 32);
#endif
	if (x == SIZE_T_MAX)
		return ((8 << LG_SIZEOF_PTR) - 1);
	x++;
	return (ffs_zu(x) - 2);
}
#endif

/* Set error code. */
JEMALLOC_INLINE void
set_errno(int errnum)
{
#ifdef _WIN32
	SetLastError(errnum);
#else
	errno = errnum;
#endif
}

/* Get last error code. */
JEMALLOC_INLINE int
get_errno(void)
{
#ifdef _WIN32
	return (GetLastError());
#else
	return (errno);
#endif
}
#endif

#endif /* JEMALLOC_INTERNAL_UTIL_INLINES_H */