Use FOLLY_DEPRECATED rather than directly using GCC specific attributes.

[folly.git] / folly / Bits.h

diff --git a/folly/Bits.h b/folly/Bits.h
index 0b45f84f36c066204ef41310c37de8c568a15a54..b6d0a23e2a7c044ca37c1455bafb64bc0f957739 100644 (file)
--- a/folly/Bits.h
+++ b/folly/Bits.h
@@ -1,5 +1,5 @@
 /*
- * Copyright 2013 Facebook, Inc.
+ * Copyright 2015 Facebook, Inc.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -55,23 +55,19 @@
 #ifndef FOLLY_BITS_H_
 #define FOLLY_BITS_H_
 
-#include "folly/Portability.h"
-
-#ifndef _GNU_SOURCE
-#define _GNU_SOURCE 1
-#endif
-
-#ifndef __GNUC__
-#error GCC required
+#if !defined(__clang__) && !(defined(_MSC_VER) && (_MSC_VER < 1900))
+#define FOLLY_INTRINSIC_CONSTEXPR constexpr
+#else
+// GCC and MSVC 2015+ are the only compilers with
+// intrinsics constexpr.
+#define FOLLY_INTRINSIC_CONSTEXPR const
 #endif
 
-#ifndef FOLLY_NO_CONFIG
-#include "folly/folly-config.h"
-#endif
+#include <folly/Portability.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>
@@ -90,7 +86,7 @@ namespace folly {
 // 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 &&
@@ -101,7 +97,7 @@ typename std::enable_if<
 }
 
 template <class T>
-inline constexpr
+inline FOLLY_INTRINSIC_CONSTEXPR
 typename std::enable_if<
   (std::is_integral<T>::value &&
    std::is_unsigned<T>::value &&
@@ -113,7 +109,7 @@ typename std::enable_if<
 }
 
 template <class T>
-inline constexpr
+inline FOLLY_INTRINSIC_CONSTEXPR
 typename std::enable_if<
   (std::is_integral<T>::value &&
    std::is_unsigned<T>::value &&
@@ -125,7 +121,7 @@ typename std::enable_if<
 }
 
 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
@@ -139,7 +135,7 @@ 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>
-inline constexpr
+inline FOLLY_INTRINSIC_CONSTEXPR
 typename std::enable_if<
   (std::is_integral<T>::value &&
    std::is_unsigned<T>::value &&
@@ -150,7 +146,7 @@ typename std::enable_if<
 }
 
 template <class T>
-inline constexpr
+inline FOLLY_INTRINSIC_CONSTEXPR
 typename std::enable_if<
   (std::is_integral<T>::value &&
    std::is_unsigned<T>::value &&
@@ -162,7 +158,7 @@ typename std::enable_if<
 }
 
 template <class T>
-inline constexpr
+inline FOLLY_INTRINSIC_CONSTEXPR
 typename std::enable_if<
   (std::is_integral<T>::value &&
    std::is_unsigned<T>::value &&
@@ -174,7 +170,7 @@ typename std::enable_if<
 }
 
 template <class T>
-inline constexpr
+inline FOLLY_INTRINSIC_CONSTEXPR
 typename std::enable_if<
   (std::is_integral<T>::value &&
    std::is_signed<T>::value),
@@ -184,7 +180,7 @@ typename std::enable_if<
 }
 
 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
@@ -236,6 +232,8 @@ struct EndianIntBase {
   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.
@@ -253,6 +251,8 @@ our_bswap16(Int16 x) {
 }
 #endif
 
+#endif
+
 #define FB_GEN(t, fn) \
 template<> inline t EndianIntBase<t>::swap(t x) { return fn(x); }
 
@@ -261,12 +261,21 @@ 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
 
@@ -338,10 +347,12 @@ class Endian {
     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
@@ -370,7 +381,7 @@ class BitIterator
   /**
    * 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
@@ -382,11 +393,14 @@ class BitIterator
    * 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());
   }
+  #pragma GCC diagnostic pop
 
   size_t bitOffset() const {
     return bitOffset_;
@@ -453,10 +467,10 @@ class BitIterator
   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_;
 };
 
 /**
@@ -518,6 +532,7 @@ template <class T, class Enable=void> struct Unaligned;
 /**
  * Representation of an unaligned value of a POD type.
  */
+FOLLY_PACK_PUSH
 template <class T>
 struct Unaligned<
     T,
@@ -525,7 +540,8 @@ struct Unaligned<
   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.
@@ -550,4 +566,3 @@ inline void storeUnaligned(void* p, T value) {
 }  // namespace folly
 
 #endif /* FOLLY_BITS_H_ */
-