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#ifndef SIMDUTF_VALID_UTF32_TO_LATIN1_H
#define SIMDUTF_VALID_UTF32_TO_LATIN1_H
namespace simdutf {
namespace scalar {
namespace {
namespace utf32_to_latin1 {
inline size_t convert_valid(const char32_t *buf, size_t len,
char *latin1_output) {
const uint32_t *data = reinterpret_cast<const uint32_t *>(buf);
char *start = latin1_output;
uint32_t utf32_char;
size_t pos = 0;
while (pos < len) {
utf32_char = (uint32_t)data[pos];
if (pos + 2 <=
len) { // if it is safe to read 8 more bytes, check that they are Latin1
uint64_t v;
::memcpy(&v, data + pos, sizeof(uint64_t));
if ((v & 0xFFFFFF00FFFFFF00) == 0) {
*latin1_output++ = char(buf[pos]);
*latin1_output++ = char(buf[pos + 1]);
pos += 2;
continue;
} else {
// output can not be represented in latin1
return 0;
}
}
if ((utf32_char & 0xFFFFFF00) == 0) {
*latin1_output++ = char(utf32_char);
} else {
// output can not be represented in latin1
return 0;
}
pos++;
}
return latin1_output - start;
}
} // namespace utf32_to_latin1
} // unnamed namespace
} // namespace scalar
} // namespace simdutf
#endif
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