#ifndef JEMALLOC_INTERNAL_BIT_UTIL_H

#define JEMALLOC_INTERNAL_BIT_UTIL_H

#include "jemalloc/internal/assert.h"

#define BIT_UTIL_INLINE static inline

/* 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

BIT_UTIL_INLINE unsigned

ffs_llu(unsigned long long bitmap) {

	return JEMALLOC_INTERNAL_FFSLL(bitmap);

}

BIT_UTIL_INLINE unsigned

ffs_lu(unsigned long bitmap) {

	return JEMALLOC_INTERNAL_FFSL(bitmap);

}

BIT_UTIL_INLINE unsigned

ffs_u(unsigned bitmap) {

	return JEMALLOC_INTERNAL_FFS(bitmap);

}

#ifdef JEMALLOC_INTERNAL_POPCOUNTL

BIT_UTIL_INLINE unsigned

popcount_lu(unsigned long bitmap) {

  return JEMALLOC_INTERNAL_POPCOUNTL(bitmap);

}

#endif

/*

 * Clears first unset bit in bitmap, and returns

 * place of bit.  bitmap *must not* be 0.

 */

BIT_UTIL_INLINE size_t

cfs_lu(unsigned long* bitmap) {

	size_t bit = ffs_lu(*bitmap) - 1;

	*bitmap ^= ZU(1) << bit;

	return bit;

}

BIT_UTIL_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

}

BIT_UTIL_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

}

BIT_UTIL_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);

}

BIT_UTIL_INLINE uint64_t

pow2_ceil_u64(uint64_t x) {

#if (defined(__amd64__) || defined(__x86_64__) || defined(JEMALLOC_HAVE_BUILTIN_CLZ))

	if(unlikely(x <= 1)) {

		return x;

	}

	size_t msb_on_index;

#if (defined(__amd64__) || defined(__x86_64__))

	asm ("bsrq %1, %0"

			: "=r"(msb_on_index) // Outputs.

			: "r"(x-1)           // Inputs.

		);

#elif (defined(JEMALLOC_HAVE_BUILTIN_CLZ))

	msb_on_index = (63 ^ __builtin_clzll(x - 1));

#endif

	assert(msb_on_index < 63);

	return 1ULL << (msb_on_index + 1);

#else

	x--;

	x |= x >> 1;

	x |= x >> 2;

	x |= x >> 4;

	x |= x >> 8;

	x |= x >> 16;

	x |= x >> 32;

	x++;

	return x;

#endif

}

BIT_UTIL_INLINE uint32_t

pow2_ceil_u32(uint32_t x) {

#if ((defined(__i386__) || defined(JEMALLOC_HAVE_BUILTIN_CLZ)) && (!defined(__s390__)))

	if(unlikely(x <= 1)) {

		return x;

	}

	size_t msb_on_index;

#if (defined(__i386__))

	asm ("bsr %1, %0"

			: "=r"(msb_on_index) // Outputs.

			: "r"(x-1)           // Inputs.

		);

#elif (defined(JEMALLOC_HAVE_BUILTIN_CLZ))

	msb_on_index = (31 ^ __builtin_clz(x - 1));

#endif

	assert(msb_on_index < 31);

	return 1U << (msb_on_index + 1);

#else

	x--;

	x |= x >> 1;

	x |= x >> 2;

	x |= x >> 4;

	x |= x >> 8;

	x |= x >> 16;

	x++;

	return x;

#endif

}

/* Compute the smallest power of 2 that is >= x. */

BIT_UTIL_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__))

BIT_UTIL_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))

BIT_UTIL_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))

BIT_UTIL_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

BIT_UTIL_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

BIT_UTIL_INLINE unsigned

lg_ceil(size_t x) {

	return lg_floor(x) + ((x & (x - 1)) == 0 ? 0 : 1);

}

#undef BIT_UTIL_INLINE

/* A compile-time version of lg_floor and lg_ceil. */

#define LG_FLOOR_1(x) 0

#define LG_FLOOR_2(x) (x < (1ULL << 1) ? LG_FLOOR_1(x) : 1 + LG_FLOOR_1(x >> 1))

#define LG_FLOOR_4(x) (x < (1ULL << 2) ? LG_FLOOR_2(x) : 2 + LG_FLOOR_2(x >> 2))

#define LG_FLOOR_8(x) (x < (1ULL << 4) ? LG_FLOOR_4(x) : 4 + LG_FLOOR_4(x >> 4))

#define LG_FLOOR_16(x) (x < (1ULL << 8) ? LG_FLOOR_8(x) : 8 + LG_FLOOR_8(x >> 8))

#define LG_FLOOR_32(x) (x < (1ULL << 16) ? LG_FLOOR_16(x) : 16 + LG_FLOOR_16(x >> 16))

#define LG_FLOOR_64(x) (x < (1ULL << 32) ? LG_FLOOR_32(x) : 32 + LG_FLOOR_32(x >> 32))

#if LG_SIZEOF_PTR == 2

#  define LG_FLOOR(x) LG_FLOOR_32((x))

#else

#  define LG_FLOOR(x) LG_FLOOR_64((x))

#endif

#define LG_CEIL(x) (LG_FLOOR(x) + (((x) & ((x) - 1)) == 0 ? 0 : 1))

#endif /* JEMALLOC_INTERNAL_BIT_UTIL_H */