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// If we have 32-bit ints, pick off 3 bytes at a time for as long as we can,
// but ensure that there are at least 4 bytes available to avoid segfaulting:
while (srclen >= 4)
{
// Load string:
uint32_t str = *(uint32_t *)c;
// Reorder to 32-bit big-endian, if not already in that format. The
// workset must be in big-endian, otherwise the shifted bits do not
// carry over properly among adjacent bytes:
str = cpu_to_be32(str);
// Shift input by 6 bytes each round and mask in only the lower 6 bits;
// look up the character in the Base64 encoding table and write it to
// the output location:
*o++ = neon32_base64_table_enc[(str >> 26) & 0x3F];
*o++ = neon32_base64_table_enc[(str >> 20) & 0x3F];
*o++ = neon32_base64_table_enc[(str >> 14) & 0x3F];
*o++ = neon32_base64_table_enc[(str >> 8) & 0x3F];
c += 3; // 3 bytes of input
outl += 4; // 4 bytes of output
srclen -= 3;
}
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