/**
* Fallback implementation for finding the first non-ASCII character in a
* UTF-16 string.
*/
static inline int32_t
FirstNonASCIIUnvectorized(const char16_t* aBegin, const char16_t* aEnd)
{
typedef mozilla::NonASCIIParameters<sizeof(size_t)> p;
const size_t kMask = p::mask();
const uintptr_t kAlignMask = p::alignMask();
const size_t kNumUnicharsPerWord = p::numUnicharsPerWord();
const char16_t* idx = aBegin;
// Align ourselves to a word boundary.
for (; idx != aEnd && ((uintptr_t(idx) & kAlignMask) != 0); idx++) {
if (!IsASCII(*idx)) {
return idx - aBegin;
}
}
// Check one word at a time.
const char16_t* wordWalkEnd = mozilla::aligned(aEnd, kAlignMask);
for (; idx != wordWalkEnd; idx += kNumUnicharsPerWord) {
const size_t word = *reinterpret_cast<const size_t*>(idx);
if (word & kMask) {
return idx - aBegin;
}
}
// Take care of the remainder one character at a time.
for (; idx != aEnd; idx++) {
if (!IsASCII(*idx)) {
return idx - aBegin;
}
}
return -1;
}
