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struct/class consistency
[folly.git]
/
folly
/
Bits.h
diff --git
a/folly/Bits.h
b/folly/Bits.h
index d9bf1ad09119ac287d3d6a5758cec706d795205e..4c1182a633c99dbac620a4e251065d47e77631f6 100644
(file)
--- a/
folly/Bits.h
+++ b/
folly/Bits.h
@@
-1,5
+1,5
@@
/*
/*
- * Copyright 201
3
Facebook, Inc.
+ * Copyright 201
5
Facebook, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
@@
-55,28
+55,33
@@
#ifndef FOLLY_BITS_H_
#define FOLLY_BITS_H_
#ifndef FOLLY_BITS_H_
#define FOLLY_BITS_H_
-#include "folly/Portability.h"
-
-#ifndef _GNU_SOURCE
-#define _GNU_SOURCE 1
+#if !defined(__clang__) && !defined(_MSC_VER)
+#define FOLLY_INTRINSIC_CONSTEXPR constexpr
+#else
+// GCC is the only compiler with intrinsics constexpr.
+#define FOLLY_INTRINSIC_CONSTEXPR const
#endif
#endif
-#ifndef __GNUC__
-#error GCC required
-#endif
+#include <folly/Portability.h>
-#include "folly/folly-config.h"
-#include "folly/detail/BitsDetail.h"
-#include "folly/detail/BitIteratorDetail.h"
-#include "folly/Likely.h"
+#include <folly/detail/BitsDetail.h>
+#include <folly/detail/BitIteratorDetail.h>
+#include <folly/Likely.h>
#if FOLLY_HAVE_BYTESWAP_H
# include <byteswap.h>
#endif
#if FOLLY_HAVE_BYTESWAP_H
# include <byteswap.h>
#endif
+#ifdef _MSC_VER
+# include <intrin.h>
+# pragma intrinsic(_BitScanForward)
+# pragma intrinsic(_BitScanForward64)
+# pragma intrinsic(_BitScanReverse)
+# pragma intrinsic(_BitScanReverse64)
+#endif
+
#include <cassert>
#include <cinttypes>
#include <cassert>
#include <cinttypes>
-#include <endian.h>
#include <iterator>
#include <limits>
#include <type_traits>
#include <iterator>
#include <limits>
#include <type_traits>
@@
-88,18
+93,23
@@
namespace folly {
// Generate overloads for findFirstSet as wrappers around
// appropriate ffs, ffsl, ffsll gcc builtins
template <class T>
// Generate overloads for findFirstSet as wrappers around
// appropriate ffs, ffsl, ffsll gcc builtins
template <class T>
-inline
constexpr
+inline
FOLLY_INTRINSIC_CONSTEXPR
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
sizeof(T) <= sizeof(unsigned int)),
unsigned int>::type
findFirstSet(T x) {
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
sizeof(T) <= sizeof(unsigned int)),
unsigned int>::type
findFirstSet(T x) {
+#ifdef _MSC_VER
+ unsigned long index;
+ return _BitScanForward(&index, x) ? index : 0;
+#else
return __builtin_ffs(x);
return __builtin_ffs(x);
+#endif
}
template <class T>
}
template <class T>
-inline
constexpr
+inline
FOLLY_INTRINSIC_CONSTEXPR
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
@@
-107,11
+117,16
@@
typename std::enable_if<
sizeof(T) <= sizeof(unsigned long)),
unsigned int>::type
findFirstSet(T x) {
sizeof(T) <= sizeof(unsigned long)),
unsigned int>::type
findFirstSet(T x) {
+#ifdef _MSC_VER
+ unsigned long index;
+ return _BitScanForward(&index, x) ? index : 0;
+#else
return __builtin_ffsl(x);
return __builtin_ffsl(x);
+#endif
}
template <class T>
}
template <class T>
-inline
constexpr
+inline
FOLLY_INTRINSIC_CONSTEXPR
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
@@
-119,11
+134,16
@@
typename std::enable_if<
sizeof(T) <= sizeof(unsigned long long)),
unsigned int>::type
findFirstSet(T x) {
sizeof(T) <= sizeof(unsigned long long)),
unsigned int>::type
findFirstSet(T x) {
+#ifdef _MSC_VER
+ unsigned long index;
+ return _BitScanForward64(&index, x) ? index : 0;
+#else
return __builtin_ffsll(x);
return __builtin_ffsll(x);
+#endif
}
template <class T>
}
template <class T>
-inline
constexpr
+inline
FOLLY_INTRINSIC_CONSTEXPR
typename std::enable_if<
(std::is_integral<T>::value && std::is_signed<T>::value),
unsigned int>::type
typename std::enable_if<
(std::is_integral<T>::value && std::is_signed<T>::value),
unsigned int>::type
@@
-137,18
+157,29
@@
typename std::enable_if<
// findLastSet: return the 1-based index of the highest bit set
// for x > 0, findLastSet(x) == 1 + floor(log2(x))
template <class T>
// findLastSet: return the 1-based index of the highest bit set
// for x > 0, findLastSet(x) == 1 + floor(log2(x))
template <class T>
-inline
constexpr
+inline
FOLLY_INTRINSIC_CONSTEXPR
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
sizeof(T) <= sizeof(unsigned int)),
unsigned int>::type
findLastSet(T x) {
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
sizeof(T) <= sizeof(unsigned int)),
unsigned int>::type
findLastSet(T x) {
+#ifdef _MSC_VER
+ unsigned long index;
+ int clz;
+ if (_BitScanReverse(&index, x)) {
+ clz = static_cast<int>(31 - index);
+ } else {
+ clz = 32;
+ }
+ return x ? 8 * sizeof(unsigned int) - clz : 0;
+#else
return x ? 8 * sizeof(unsigned int) - __builtin_clz(x) : 0;
return x ? 8 * sizeof(unsigned int) - __builtin_clz(x) : 0;
+#endif
}
template <class T>
}
template <class T>
-inline
constexpr
+inline
FOLLY_INTRINSIC_CONSTEXPR
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
@@
-156,11
+187,22
@@
typename std::enable_if<
sizeof(T) <= sizeof(unsigned long)),
unsigned int>::type
findLastSet(T x) {
sizeof(T) <= sizeof(unsigned long)),
unsigned int>::type
findLastSet(T x) {
+#ifdef _MSC_VER
+ unsigned long index;
+ int clz;
+ if (_BitScanReverse(&index, x)) {
+ clz = static_cast<int>(31 - index);
+ } else {
+ clz = 32;
+ }
+ return x ? 8 * sizeof(unsigned int) - clz : 0;
+#else
return x ? 8 * sizeof(unsigned long) - __builtin_clzl(x) : 0;
return x ? 8 * sizeof(unsigned long) - __builtin_clzl(x) : 0;
+#endif
}
template <class T>
}
template <class T>
-inline
constexpr
+inline
FOLLY_INTRINSIC_CONSTEXPR
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_unsigned<T>::value &&
@@
-168,11
+210,22
@@
typename std::enable_if<
sizeof(T) <= sizeof(unsigned long long)),
unsigned int>::type
findLastSet(T x) {
sizeof(T) <= sizeof(unsigned long long)),
unsigned int>::type
findLastSet(T x) {
+#ifdef _MSC_VER
+ unsigned long index;
+ unsigned long long clz;
+ if (_BitScanReverse(&index, x)) {
+ clz = static_cast<unsigned long long>(63 - index);
+ } else {
+ clz = 64;
+ }
+ return x ? 8 * sizeof(unsigned long long) - clz : 0;
+#else
return x ? 8 * sizeof(unsigned long long) - __builtin_clzll(x) : 0;
return x ? 8 * sizeof(unsigned long long) - __builtin_clzll(x) : 0;
+#endif
}
template <class T>
}
template <class T>
-inline
constexpr
+inline
FOLLY_INTRINSIC_CONSTEXPR
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_signed<T>::value),
typename std::enable_if<
(std::is_integral<T>::value &&
std::is_signed<T>::value),
@@
-182,7
+235,7
@@
typename std::enable_if<
}
template <class T>
}
template <class T>
-inline
constexpr
+inline
FOLLY_INTRINSIC_CONSTEXPR
typename std::enable_if<
std::is_integral<T>::value && std::is_unsigned<T>::value,
T>::type
typename std::enable_if<
std::is_integral<T>::value && std::is_unsigned<T>::value,
T>::type
@@
-234,6
+287,8
@@
struct EndianIntBase {
static T swap(T x);
};
static T swap(T x);
};
+#ifndef _MSC_VER
+
/**
* If we have the bswap_16 macro from byteswap.h, use it; otherwise, provide our
* own definition.
/**
* If we have the bswap_16 macro from byteswap.h, use it; otherwise, provide our
* own definition.
@@
-251,6
+306,8
@@
our_bswap16(Int16 x) {
}
#endif
}
#endif
+#endif
+
#define FB_GEN(t, fn) \
template<> inline t EndianIntBase<t>::swap(t x) { return fn(x); }
#define FB_GEN(t, fn) \
template<> inline t EndianIntBase<t>::swap(t x) { return fn(x); }
@@
-259,16
+316,25
@@
template<> inline t EndianIntBase<t>::swap(t x) { return fn(x); }
// __builtin_bswap16 for some reason, so we have to provide our own.
FB_GEN( int8_t,)
FB_GEN(uint8_t,)
// __builtin_bswap16 for some reason, so we have to provide our own.
FB_GEN( int8_t,)
FB_GEN(uint8_t,)
+#ifdef _MSC_VER
+FB_GEN( int64_t, _byteswap_uint64)
+FB_GEN(uint64_t, _byteswap_uint64)
+FB_GEN( int32_t, _byteswap_ulong)
+FB_GEN(uint32_t, _byteswap_ulong)
+FB_GEN( int16_t, _byteswap_ushort)
+FB_GEN(uint16_t, _byteswap_ushort)
+#else
FB_GEN( int64_t, __builtin_bswap64)
FB_GEN(uint64_t, __builtin_bswap64)
FB_GEN( int32_t, __builtin_bswap32)
FB_GEN(uint32_t, __builtin_bswap32)
FB_GEN( int16_t, our_bswap16)
FB_GEN(uint16_t, our_bswap16)
FB_GEN( int64_t, __builtin_bswap64)
FB_GEN(uint64_t, __builtin_bswap64)
FB_GEN( int32_t, __builtin_bswap32)
FB_GEN(uint32_t, __builtin_bswap32)
FB_GEN( int16_t, our_bswap16)
FB_GEN(uint16_t, our_bswap16)
+#endif
#undef FB_GEN
#undef FB_GEN
-#if __BYTE_ORDER
== __LITTLE_ENDIAN
+#if __BYTE_ORDER
__ == __ORDER_LITTLE_ENDIAN__
template <class T>
struct EndianInt : public detail::EndianIntBase<T> {
template <class T>
struct EndianInt : public detail::EndianIntBase<T> {
@@
-277,7
+343,7
@@
struct EndianInt : public detail::EndianIntBase<T> {
static T little(T x) { return x; }
};
static T little(T x) { return x; }
};
-#elif __BYTE_ORDER
== __BIG_ENDIAN
+#elif __BYTE_ORDER
__ == __ORDER_BIG_ENDIAN__
template <class T>
struct EndianInt : public detail::EndianIntBase<T> {
template <class T>
struct EndianInt : public detail::EndianIntBase<T> {
@@
-288,7
+354,7
@@
struct EndianInt : public detail::EndianIntBase<T> {
#else
# error Your machine uses a weird endianness!
#else
# error Your machine uses a weird endianness!
-#endif /* __BYTE_ORDER */
+#endif /* __BYTE_ORDER
__
*/
} // namespace detail
} // namespace detail
@@
-318,13
+384,13
@@
class Endian {
};
static constexpr Order order =
};
static constexpr Order order =
-#if __BYTE_ORDER
== __LITTLE_ENDIAN
+#if __BYTE_ORDER
__ == __ORDER_LITTLE_ENDIAN__
Order::LITTLE;
Order::LITTLE;
-#elif __BYTE_ORDER
== __BIG_ENDIAN
+#elif __BYTE_ORDER
__ == __ORDER_BIG_ENDIAN__
Order::BIG;
#else
# error Your machine uses a weird endianness!
Order::BIG;
#else
# error Your machine uses a weird endianness!
-#endif /* __BYTE_ORDER */
+#endif /* __BYTE_ORDER
__
*/
template <class T> static T swap(T x) {
return detail::EndianInt<T>::swap(x);
template <class T> static T swap(T x) {
return detail::EndianInt<T>::swap(x);
@@
-336,10
+402,12
@@
class Endian {
return detail::EndianInt<T>::little(x);
}
return detail::EndianInt<T>::little(x);
}
+#if !defined(__ANDROID__)
FB_GEN(64)
FB_GEN(32)
FB_GEN(16)
FB_GEN(8)
FB_GEN(64)
FB_GEN(32)
FB_GEN(16)
FB_GEN(8)
+#endif
};
#undef FB_GEN
};
#undef FB_GEN
@@
-368,7
+436,7
@@
class BitIterator
/**
* Return the number of bits in an element of the underlying iterator.
*/
/**
* Return the number of bits in an element of the underlying iterator.
*/
- static
size_
t bitsPerBlock() {
+ static
unsigned in
t bitsPerBlock() {
return std::numeric_limits<
typename std::make_unsigned<
typename std::iterator_traits<BaseIter>::value_type
return std::numeric_limits<
typename std::make_unsigned<
typename std::iterator_traits<BaseIter>::value_type
@@
-380,11
+448,14
@@
class BitIterator
* Construct a BitIterator that points at a given bit offset (default 0)
* in iter.
*/
* Construct a BitIterator that points at a given bit offset (default 0)
* in iter.
*/
+ #pragma GCC diagnostic push // bitOffset shadows a member
+ #pragma GCC diagnostic ignored "-Wshadow"
explicit BitIterator(const BaseIter& iter, size_t bitOffset=0)
: bititerator_detail::BitIteratorBase<BaseIter>::type(iter),
bitOffset_(bitOffset) {
assert(bitOffset_ < bitsPerBlock());
}
explicit BitIterator(const BaseIter& iter, size_t bitOffset=0)
: bititerator_detail::BitIteratorBase<BaseIter>::type(iter),
bitOffset_(bitOffset) {
assert(bitOffset_ < bitsPerBlock());
}
+ #pragma GCC diagnostic pop
size_t bitOffset() const {
return bitOffset_;
size_t bitOffset() const {
return bitOffset_;
@@
-451,10
+522,10
@@
class BitIterator
ssize_t distance_to(const BitIterator& other) const {
return
(other.base_reference() - this->base_reference()) * bitsPerBlock() +
ssize_t distance_to(const BitIterator& other) const {
return
(other.base_reference() - this->base_reference()) * bitsPerBlock() +
-
(other.bitOffset_ - bitOffset_)
;
+
other.bitOffset_ - bitOffset_
;
}
}
-
ssize_
t bitOffset_;
+
unsigned in
t bitOffset_;
};
/**
};
/**
@@
-516,6
+587,7
@@
template <class T, class Enable=void> struct Unaligned;
/**
* Representation of an unaligned value of a POD type.
*/
/**
* Representation of an unaligned value of a POD type.
*/
+FOLLY_PACK_PUSH
template <class T>
struct Unaligned<
T,
template <class T>
struct Unaligned<
T,
@@
-523,7
+595,8
@@
struct Unaligned<
Unaligned() = default; // uninitialized
/* implicit */ Unaligned(T v) : value(v) { }
T value;
Unaligned() = default; // uninitialized
/* implicit */ Unaligned(T v) : value(v) { }
T value;
-} __attribute__((packed));
+} FOLLY_PACK_ATTR;
+FOLLY_PACK_POP
/**
* Read an unaligned value of type T and return it.
/**
* Read an unaligned value of type T and return it.
@@
-548,4
+621,3
@@
inline void storeUnaligned(void* p, T value) {
} // namespace folly
#endif /* FOLLY_BITS_H_ */
} // namespace folly
#endif /* FOLLY_BITS_H_ */
-