#include "llvm/Support/AlignOf.h"
#include "llvm/Support/Host.h"
#include "llvm/Support/SwapByteOrder.h"
-#include "llvm/Support/type_traits.h"
namespace llvm {
namespace support {
} // end namespace detail
namespace endian {
+/// Swap the bytes of value to match the given endianness.
template<typename value_type, endianness endian>
inline value_type byte_swap(value_type value) {
if (endian != native && sys::IsBigEndianHost != (endian == big))
- return sys::SwapByteOrder(value);
+ sys::swapByteOrder(value);
return value;
}
+/// Read a value of a particular endianness from memory.
template<typename value_type,
endianness endian,
std::size_t alignment>
return byte_swap<value_type, endian>(ret);
}
+/// Read a value of a particular endianness from a buffer, and increment the
+/// buffer past that value.
+template<typename value_type, endianness endian, std::size_t alignment,
+ typename CharT>
+inline value_type readNext(const CharT *&memory) {
+ value_type ret = read<value_type, endian, alignment>(memory);
+ memory += sizeof(value_type);
+ return ret;
+}
+
+/// Write a value to memory with a particular endianness.
template<typename value_type,
endianness endian,
std::size_t alignment>
&value,
sizeof(value_type));
}
+
+template <typename value_type>
+using make_unsigned_t = typename std::make_unsigned<value_type>::type;
+
+/// Read a value of a particular endianness from memory, for a location
+/// that starts at the given bit offset within the first byte.
+template <typename value_type, endianness endian, std::size_t alignment>
+inline value_type readAtBitAlignment(const void *memory, uint64_t startBit) {
+ assert(startBit < 8);
+ if (startBit == 0)
+ return read<value_type, endian, alignment>(memory);
+ else {
+ // Read two values and compose the result from them.
+ value_type val[2];
+ memcpy(&val[0],
+ LLVM_ASSUME_ALIGNED(
+ memory, (detail::PickAlignment<value_type, alignment>::value)),
+ sizeof(value_type) * 2);
+ val[0] = byte_swap<value_type, endian>(val[0]);
+ val[1] = byte_swap<value_type, endian>(val[1]);
+
+ // Shift bits from the lower value into place.
+ make_unsigned_t<value_type> lowerVal = val[0] >> startBit;
+ // Mask off upper bits after right shift in case of signed type.
+ make_unsigned_t<value_type> numBitsFirstVal =
+ (sizeof(value_type) * 8) - startBit;
+ lowerVal &= ((make_unsigned_t<value_type>)1 << numBitsFirstVal) - 1;
+
+ // Get the bits from the upper value.
+ make_unsigned_t<value_type> upperVal =
+ val[1] & (((make_unsigned_t<value_type>)1 << startBit) - 1);
+ // Shift them in to place.
+ upperVal <<= numBitsFirstVal;
+
+ return lowerVal | upperVal;
+ }
+}
+
+/// Write a value to memory with a particular endianness, for a location
+/// that starts at the given bit offset within the first byte.
+template <typename value_type, endianness endian, std::size_t alignment>
+inline void writeAtBitAlignment(void *memory, value_type value,
+ uint64_t startBit) {
+ assert(startBit < 8);
+ if (startBit == 0)
+ write<value_type, endian, alignment>(memory, value);
+ else {
+ // Read two values and shift the result into them.
+ value_type val[2];
+ memcpy(&val[0],
+ LLVM_ASSUME_ALIGNED(
+ memory, (detail::PickAlignment<value_type, alignment>::value)),
+ sizeof(value_type) * 2);
+ val[0] = byte_swap<value_type, endian>(val[0]);
+ val[1] = byte_swap<value_type, endian>(val[1]);
+
+ // Mask off any existing bits in the upper part of the lower value that
+ // we want to replace.
+ val[0] &= ((make_unsigned_t<value_type>)1 << startBit) - 1;
+ make_unsigned_t<value_type> numBitsFirstVal =
+ (sizeof(value_type) * 8) - startBit;
+ make_unsigned_t<value_type> lowerVal = value;
+ if (startBit > 0) {
+ // Mask off the upper bits in the new value that are not going to go into
+ // the lower value. This avoids a left shift of a negative value, which
+ // is undefined behavior.
+ lowerVal &= (((make_unsigned_t<value_type>)1 << numBitsFirstVal) - 1);
+ // Now shift the new bits into place
+ lowerVal <<= startBit;
+ }
+ val[0] |= lowerVal;
+
+ // Mask off any existing bits in the lower part of the upper value that
+ // we want to replace.
+ val[1] &= ~(((make_unsigned_t<value_type>)1 << startBit) - 1);
+ // Next shift the bits that go into the upper value into position.
+ make_unsigned_t<value_type> upperVal = value >> numBitsFirstVal;
+ // Mask off upper bits after right shift in case of signed type.
+ upperVal &= ((make_unsigned_t<value_type>)1 << startBit) - 1;
+ val[1] |= upperVal;
+
+ // Finally, rewrite values.
+ val[0] = byte_swap<value_type, endian>(val[0]);
+ val[1] = byte_swap<value_type, endian>(val[1]);
+ memcpy(LLVM_ASSUME_ALIGNED(
+ memory, (detail::PickAlignment<value_type, alignment>::value)),
+ &val[0], sizeof(value_type) * 2);
+ }
+}
} // end namespace endian
namespace detail {
(void*)Value.buffer, newValue);
}
+ packed_endian_specific_integral &operator+=(value_type newValue) {
+ *this = *this + newValue;
+ return *this;
+ }
+
+ packed_endian_specific_integral &operator-=(value_type newValue) {
+ *this = *this - newValue;
+ return *this;
+ }
+
+ packed_endian_specific_integral &operator|=(value_type newValue) {
+ *this = *this | newValue;
+ return *this;
+ }
+
+ packed_endian_specific_integral &operator&=(value_type newValue) {
+ *this = *this & newValue;
+ return *this;
+ }
+
private:
AlignedCharArray<PickAlignment<value_type, alignment>::value,
sizeof(value_type)> Value;
+
+public:
+ struct ref {
+ explicit ref(void *Ptr) : Ptr(Ptr) {}
+
+ operator value_type() const {
+ return endian::read<value_type, endian, alignment>(Ptr);
+ }
+
+ void operator=(value_type NewValue) {
+ endian::write<value_type, endian, alignment>(Ptr, NewValue);
+ }
+
+ private:
+ void *Ptr;
+ };
};
+
} // end namespace detail
-typedef detail::packed_endian_specific_integral
- <uint8_t, little, unaligned> ulittle8_t;
typedef detail::packed_endian_specific_integral
<uint16_t, little, unaligned> ulittle16_t;
typedef detail::packed_endian_specific_integral
typedef detail::packed_endian_specific_integral
<uint64_t, little, unaligned> ulittle64_t;
-typedef detail::packed_endian_specific_integral
- <int8_t, little, unaligned> little8_t;
typedef detail::packed_endian_specific_integral
<int16_t, little, unaligned> little16_t;
typedef detail::packed_endian_specific_integral
typedef detail::packed_endian_specific_integral
<int64_t, little, unaligned> little64_t;
-typedef detail::packed_endian_specific_integral
- <uint8_t, little, aligned> aligned_ulittle8_t;
typedef detail::packed_endian_specific_integral
<uint16_t, little, aligned> aligned_ulittle16_t;
typedef detail::packed_endian_specific_integral
typedef detail::packed_endian_specific_integral
<uint64_t, little, aligned> aligned_ulittle64_t;
-typedef detail::packed_endian_specific_integral
- <int8_t, little, aligned> aligned_little8_t;
typedef detail::packed_endian_specific_integral
<int16_t, little, aligned> aligned_little16_t;
typedef detail::packed_endian_specific_integral
typedef detail::packed_endian_specific_integral
<int64_t, little, aligned> aligned_little64_t;
-typedef detail::packed_endian_specific_integral
- <uint8_t, big, unaligned> ubig8_t;
typedef detail::packed_endian_specific_integral
<uint16_t, big, unaligned> ubig16_t;
typedef detail::packed_endian_specific_integral
typedef detail::packed_endian_specific_integral
<uint64_t, big, unaligned> ubig64_t;
-typedef detail::packed_endian_specific_integral
- <int8_t, big, unaligned> big8_t;
typedef detail::packed_endian_specific_integral
<int16_t, big, unaligned> big16_t;
typedef detail::packed_endian_specific_integral
typedef detail::packed_endian_specific_integral
<int64_t, big, unaligned> big64_t;
-typedef detail::packed_endian_specific_integral
- <uint8_t, big, aligned> aligned_ubig8_t;
typedef detail::packed_endian_specific_integral
<uint16_t, big, aligned> aligned_ubig16_t;
typedef detail::packed_endian_specific_integral
typedef detail::packed_endian_specific_integral
<uint64_t, big, aligned> aligned_ubig64_t;
-typedef detail::packed_endian_specific_integral
- <int8_t, big, aligned> aligned_big8_t;
typedef detail::packed_endian_specific_integral
<int16_t, big, aligned> aligned_big16_t;
typedef detail::packed_endian_specific_integral
<int32_t, native, unaligned> unaligned_int32_t;
typedef detail::packed_endian_specific_integral
<int64_t, native, unaligned> unaligned_int64_t;
-} // end namespace llvm
+
+namespace endian {
+template <typename T, endianness E> inline T read(const void *P) {
+ return *(const detail::packed_endian_specific_integral<T, E, unaligned> *)P;
+}
+
+template <endianness E> inline uint16_t read16(const void *P) {
+ return read<uint16_t, E>(P);
+}
+template <endianness E> inline uint32_t read32(const void *P) {
+ return read<uint32_t, E>(P);
+}
+template <endianness E> inline uint64_t read64(const void *P) {
+ return read<uint64_t, E>(P);
+}
+
+inline uint16_t read16le(const void *P) { return read16<little>(P); }
+inline uint32_t read32le(const void *P) { return read32<little>(P); }
+inline uint64_t read64le(const void *P) { return read64<little>(P); }
+inline uint16_t read16be(const void *P) { return read16<big>(P); }
+inline uint32_t read32be(const void *P) { return read32<big>(P); }
+inline uint64_t read64be(const void *P) { return read64<big>(P); }
+
+template <typename T, endianness E> inline void write(void *P, T V) {
+ *(detail::packed_endian_specific_integral<T, E, unaligned> *)P = V;
+}
+
+template <endianness E> inline void write16(void *P, uint16_t V) {
+ write<uint16_t, E>(P, V);
+}
+template <endianness E> inline void write32(void *P, uint32_t V) {
+ write<uint32_t, E>(P, V);
+}
+template <endianness E> inline void write64(void *P, uint64_t V) {
+ write<uint64_t, E>(P, V);
+}
+
+inline void write16le(void *P, uint16_t V) { write16<little>(P, V); }
+inline void write32le(void *P, uint32_t V) { write32<little>(P, V); }
+inline void write64le(void *P, uint64_t V) { write64<little>(P, V); }
+inline void write16be(void *P, uint16_t V) { write16<big>(P, V); }
+inline void write32be(void *P, uint32_t V) { write32<big>(P, V); }
+inline void write64be(void *P, uint64_t V) { write64<big>(P, V); }
+} // end namespace endian
} // end namespace support
+} // end namespace llvm
#endif