#ifndef ASCIIFastPath_h
#define ASCIIFastPath_h
#include "wtf/Alignment.h"
#include "wtf/CPU.h"
#include "wtf/StdLibExtras.h"
#include "wtf/unicode/Unicode.h"
#include <stdint.h>
#if OS(MACOSX) && (CPU(X86) || CPU(X86_64))
#include <emmintrin.h>
#endif
namespace WTF {
typedef uintptr_t MachineWord;
const uintptr_t machineWordAlignmentMask = sizeof(MachineWord) - 1;
inline bool isAlignedToMachineWord(const void* pointer)
{
return !(reinterpret_cast<uintptr_t>(pointer) & machineWordAlignmentMask);
}
template<typename T> inline T* alignToMachineWord(T* pointer)
{
return reinterpret_cast<T*>(reinterpret_cast<uintptr_t>(pointer) & ~machineWordAlignmentMask);
}
template<size_t size, typename CharacterType> struct NonASCIIMask;
template<> struct NonASCIIMask<4, UChar> {
static inline uint32_t value() { return 0xFF80FF80U; }
};
template<> struct NonASCIIMask<4, LChar> {
static inline uint32_t value() { return 0x80808080U; }
};
template<> struct NonASCIIMask<8, UChar> {
static inline uint64_t value() { return 0xFF80FF80FF80FF80ULL; }
};
template<> struct NonASCIIMask<8, LChar> {
static inline uint64_t value() { return 0x8080808080808080ULL; }
};
template<typename CharacterType>
inline bool isAllASCII(MachineWord word)
{
return !(word & NonASCIIMask<sizeof(MachineWord), CharacterType>::value());
}
template<typename CharacterType>
inline bool charactersAreAllASCII(const CharacterType* characters, size_t length)
{
MachineWord allCharBits = 0;
const CharacterType* end = characters + length;
while (!isAlignedToMachineWord(characters) && characters != end) {
allCharBits |= *characters;
++characters;
}
const CharacterType* wordEnd = alignToMachineWord(end);
const size_t loopIncrement = sizeof(MachineWord) / sizeof(CharacterType);
while (characters < wordEnd) {
allCharBits |= *(reinterpret_cast_ptr<const MachineWord*>(characters));
characters += loopIncrement;
}
while (characters != end) {
allCharBits |= *characters;
++characters;
}
MachineWord nonASCIIBitMask = NonASCIIMask<sizeof(MachineWord), CharacterType>::value();
return !(allCharBits & nonASCIIBitMask);
}
inline void copyLCharsFromUCharSource(LChar* destination, const UChar* source, size_t length)
{
#if OS(MACOSX) && (CPU(X86) || CPU(X86_64))
const uintptr_t memoryAccessSize = 16;
const uintptr_t memoryAccessMask = memoryAccessSize - 1;
size_t i = 0;
for (;i < length && !isAlignedTo<memoryAccessMask>(&source[i]); ++i) {
ASSERT(!(source[i] & 0xff00));
destination[i] = static_cast<LChar>(source[i]);
}
const uintptr_t sourceLoadSize = 32;
const size_t ucharsPerLoop = sourceLoadSize / sizeof(UChar);
if (length > ucharsPerLoop) {
const size_t endLength = length - ucharsPerLoop + 1;
for (; i < endLength; i += ucharsPerLoop) {
#ifndef NDEBUG
for (unsigned checkIndex = 0; checkIndex < ucharsPerLoop; ++checkIndex)
ASSERT(!(source[i+checkIndex] & 0xff00));
#endif
__m128i first8UChars = _mm_load_si128(reinterpret_cast<const __m128i*>(&source[i]));
__m128i second8UChars = _mm_load_si128(reinterpret_cast<const __m128i*>(&source[i+8]));
__m128i packedChars = _mm_packus_epi16(first8UChars, second8UChars);
_mm_storeu_si128(reinterpret_cast<__m128i*>(&destination[i]), packedChars);
}
}
for (; i < length; ++i) {
ASSERT(!(source[i] & 0xff00));
destination[i] = static_cast<LChar>(source[i]);
}
#elif COMPILER(GCC) && CPU(ARM_NEON) && !(CPU(BIG_ENDIAN) || CPU(MIDDLE_ENDIAN)) && defined(NDEBUG)
const LChar* const end = destination + length;
const uintptr_t memoryAccessSize = 8;
if (length >= (2 * memoryAccessSize) - 1) {
const uintptr_t memoryAccessMask = memoryAccessSize - 1;
while (!isAlignedTo<memoryAccessMask>(destination))
*destination++ = static_cast<LChar>(*source++);
const uintptr_t lengthLeft = end - destination;
const LChar* const simdEnd = end - (lengthLeft % memoryAccessSize);
do {
asm("vld2.8 { d0-d1 }, [%[SOURCE]] !\n\t"
"vst1.8 { d0 }, [%[DESTINATION],:64] !\n\t"
: [SOURCE]"+r" (source), [DESTINATION]"+r" (destination)
:
: "memory", "d0", "d1");
} while (destination != simdEnd);
}
while (destination != end)
*destination++ = static_cast<LChar>(*source++);
#else
for (size_t i = 0; i < length; ++i) {
ASSERT(!(source[i] & 0xff00));
destination[i] = static_cast<LChar>(source[i]);
}
#endif
}
}
#endif