/*
- * Copyright 2014 Facebook, Inc.
+ * Copyright 2016 Facebook, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* @author Tudor Bosman (tudorb@fb.com)
*/
-#ifndef FOLLY_BITS_H_
-#define FOLLY_BITS_H_
+#pragma once
-#include <folly/Portability.h>
-
-#ifndef __GNUC__
-#error GCC required
-#endif
-
-#ifndef __clang__
+#if !defined(__clang__) && !(defined(_MSC_VER) && (_MSC_VER < 1900))
#define FOLLY_INTRINSIC_CONSTEXPR constexpr
#else
-// Unlike GCC, in Clang (as of 3.2) intrinsics aren't constexpr.
+// GCC and MSVC 2015+ are the only compilers with
+// intrinsics constexpr.
#define FOLLY_INTRINSIC_CONSTEXPR const
#endif
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.
}
#endif
+#endif
+
#define FB_GEN(t, fn) \
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,)
+#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)
+#endif
#undef FB_GEN
return detail::EndianInt<T>::little(x);
}
+#if !defined(__ANDROID__)
FB_GEN(64)
FB_GEN(32)
FB_GEN(16)
FB_GEN(8)
+#endif
};
#undef FB_GEN
/**
* Return the number of bits in an element of the underlying iterator.
*/
- static size_t bitsPerBlock() {
+ static unsigned int bitsPerBlock() {
return std::numeric_limits<
typename std::make_unsigned<
typename std::iterator_traits<BaseIter>::value_type
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 int bitOffset_;
};
/**
inline T loadUnaligned(const void* p) {
static_assert(sizeof(Unaligned<T>) == sizeof(T), "Invalid unaligned size");
static_assert(alignof(Unaligned<T>) == 1, "Invalid alignment");
- return static_cast<const Unaligned<T>*>(p)->value;
+ if (kHasUnalignedAccess) {
+ return static_cast<const Unaligned<T>*>(p)->value;
+ } else {
+ T value;
+ memcpy(&value, p, sizeof(T));
+ return value;
+ }
}
/**
inline void storeUnaligned(void* p, T value) {
static_assert(sizeof(Unaligned<T>) == sizeof(T), "Invalid unaligned size");
static_assert(alignof(Unaligned<T>) == 1, "Invalid alignment");
- new (p) Unaligned<T>(value);
+ if (kHasUnalignedAccess) {
+ new (p) Unaligned<T>(value);
+ } else {
+ memcpy(p, &value, sizeof(T));
+ }
}
} // namespace folly
-
-#endif /* FOLLY_BITS_H_ */