#if !STRINGLIB_IS_UNICODE && STRINGLIB_SIZEOF_CHAR > 1

# error "find_max_char.h is specific to Unicode"

#if (SIZEOF_SIZE_T == 8)

# define UCS1_ASCII_CHAR_MASK 0x8080808080808080ULL

#elif (SIZEOF_SIZE_T == 4)

# define UCS1_ASCII_CHAR_MASK 0x80808080U

# error C 'size_t' size should be either 4 or 8!

#if STRINGLIB_SIZEOF_CHAR == 1

Py_LOCAL_INLINE(Py_UCS4)

STRINGLIB(find_max_char)(const STRINGLIB_CHAR *begin, const STRINGLIB_CHAR *end)

{

const unsigned char *p = (const unsigned char *) begin;

const unsigned char *_end = (const unsigned char *)end;

while (p < _end) {

if (_Py_IS_ALIGNED(p, ALIGNOF_SIZE_T)) {

/* Help register allocation */

const unsigned char *_p = p;

while (_p + SIZEOF_SIZE_T <= _end) {

size_t value = *(const size_t *) _p;

if (value & UCS1_ASCII_CHAR_MASK)

return 255;

_p += SIZEOF_SIZE_T;

}

p = _p;

if (p == _end)

break;

}

if (*p++ & 0x80)

return 255;

}

return 127;

}

#undef ASCII_CHAR_MASK

#else /* STRINGLIB_SIZEOF_CHAR == 1 */

#define MASK_ASCII 0xFFFFFF80

#define MASK_UCS1 0xFFFFFF00

#define MASK_UCS2 0xFFFF0000

#define MAX_CHAR_ASCII 0x7f

#define MAX_CHAR_UCS1 0xff

#define MAX_CHAR_UCS2 0xffff

#define MAX_CHAR_UCS4 0x10ffff

Py_LOCAL_INLINE(Py_UCS4)

STRINGLIB(find_max_char)(const STRINGLIB_CHAR *begin, const STRINGLIB_CHAR *end)

{

#if STRINGLIB_SIZEOF_CHAR == 2

const Py_UCS4 mask_limit = MASK_UCS1;

const Py_UCS4 max_char_limit = MAX_CHAR_UCS2;

#elif STRINGLIB_SIZEOF_CHAR == 4

const Py_UCS4 mask_limit = MASK_UCS2;

const Py_UCS4 max_char_limit = MAX_CHAR_UCS4;

#error Invalid STRINGLIB_SIZEOF_CHAR (must be 1, 2 or 4)

Py_UCS4 mask;

Py_ssize_t n = end - begin;

const STRINGLIB_CHAR *p = begin;

const STRINGLIB_CHAR *unrolled_end = begin + _Py_SIZE_ROUND_DOWN(n, 4);

Py_UCS4 max_char;

max_char = MAX_CHAR_ASCII;

mask = MASK_ASCII;

while (p < unrolled_end) {

STRINGLIB_CHAR bits = p[0] | p[1] | p[2] | p[3];

if (bits & mask) {

if (mask == mask_limit) {

/* Limit reached */

return max_char_limit;

}

if (mask == MASK_ASCII) {

max_char = MAX_CHAR_UCS1;

mask = MASK_UCS1;

}

else {

/* mask can't be MASK_UCS2 because of mask_limit above */

assert(mask == MASK_UCS1);

max_char = MAX_CHAR_UCS2;

mask = MASK_UCS2;

}

/* We check the new mask on the same chars in the next iteration */

continue;

}

p += 4;

}

while (p < end) {

if (p[0] & mask) {

if (mask == mask_limit) {

/* Limit reached */

return max_char_limit;

}

if (mask == MASK_ASCII) {

max_char = MAX_CHAR_UCS1;

mask = MASK_UCS1;

}

else {

/* mask can't be MASK_UCS2 because of mask_limit above */

assert(mask == MASK_UCS1);

max_char = MAX_CHAR_UCS2;

mask = MASK_UCS2;

}

/* We check the new mask on the same chars in the next iteration */

continue;

}

p++;

}

return max_char;

}

#undef MASK_ASCII

#undef MASK_UCS1

#undef MASK_UCS2

#undef MAX_CHAR_ASCII

#undef MAX_CHAR_UCS1

#undef MAX_CHAR_UCS2

#undef MAX_CHAR_UCS4

#endif /* STRINGLIB_SIZEOF_CHAR == 1 */