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/* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
// This file should only be compiled if you're on LoongArch64.
#include <lsxintrin.h>
#include "CharacterDataBufferImpl.h"
#include "nscore.h"
namespace mozilla {
namespace LSX {
int32_t FirstNon8Bit(const char16_t* str, const char16_t* end) {
using p = Non8BitParameters<sizeof(size_t)>;
const size_t mask = p::mask();
const uint32_t numUnicharsPerWord = p::numUnicharsPerWord();
const uint32_t len = end - str;
uint32_t i = 0;
// Check 8 unichars at a time.
const uint32_t vectWalkEnd = (len / 8) * 8;
// Zero-extend 0x01 to 16-bit, then shift left by 8 bits, then broadcast.
const __m128i kVec0x100u16x8 = __lsx_vldi(-0xaff);
// TODO(loongarch64): Experimenting on Loongson 3B6000 showed that unrolling
// this loop then vand.v these N results performs better on long inputs.
for (; i < vectWalkEnd; i += 8) {
__m128i vect = __lsx_vld(str + i, 0);
// Contrary to intuition, __lsx_bz_h() means "branch if any 16-bit lane is
// zero".
if (__lsx_bz_h(__lsx_vslt_hu(vect, kVec0x100u16x8))) {
return int32_t(i);
}
}
// Check one word at a time.
const uint32_t wordWalkEnd =
((len - i) / numUnicharsPerWord) * numUnicharsPerWord;
for (; i < wordWalkEnd; i += numUnicharsPerWord) {
const size_t word = *reinterpret_cast<const size_t*>(str + i);
if (word & mask) return int32_t(i);
}
// Take care of the remainder one character at a time.
for (; i < len; i++) {
if (str[i] > 255) {
return int32_t(i);
}
}
return -1;
}
} // namespace LSX
} // namespace mozilla