slow5lib-sys 0.2.0

Low-level bindings to the slow5lib C library
Documentation 
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// contributed by aqrit
// NOTE: I make this static to prevent name clashes
static size_t streamvbyte_encode_SSSE3 (const uint32_t* in, uint32_t count, uint8_t* out) {
	uint32_t keyLen = (count >> 2) + (((count & 3) + 3) >> 2); // 2-bits per each rounded up to byte boundry
	uint8_t *restrict keyPtr = &out[0];
	uint8_t *restrict dataPtr = &out[keyLen]; // variable length data after keys

	const __m128i mask_01 = _mm_set1_epi8(0x01);
	const __m128i mask_7F00 = _mm_set1_epi16(0x7F00);

	for (const uint32_t* end = &in[(count & ~7)]; in != end; in += 8)
	{
		__m128i r0, r1, r2, r3;
		size_t keys;

		r0 = _mm_loadu_si128((__m128i*)&in[0]);
		r1 = _mm_loadu_si128((__m128i*)&in[4]);

		r2 = _mm_min_epu8(mask_01, r0);
		r3 = _mm_min_epu8(mask_01, r1);
		r2 = _mm_packus_epi16(r2, r3);
		r2 = _mm_min_epi16(r2, mask_01); // convert 0x01FF to 0x0101
		r2 = _mm_adds_epu16(r2, mask_7F00); // convert: 0x0101 to 0x8001, 0xFF01 to 0xFFFF
		keys = (size_t)_mm_movemask_epi8(r2);

		r2 = _mm_loadu_si128((__m128i*)&shuf_lut[(keys << 4) & 0x03F0]);
		r3 = _mm_loadu_si128((__m128i*)&shuf_lut[(keys >> 4) & 0x03F0]);
		r0 = _mm_shuffle_epi8(r0, r2);
		r1 = _mm_shuffle_epi8(r1, r3);

		_mm_storeu_si128((__m128i *)dataPtr, r0);
		dataPtr += len_lut[keys & 0xFF];
		_mm_storeu_si128((__m128i *)dataPtr, r1);
		dataPtr += len_lut[keys >> 8];

		*((uint16_t*)keyPtr) = (uint16_t)keys;
		keyPtr += 2;
	}

	// do remaining
	uint32_t key = 0;
	for(size_t i = 0; i < (count & 7); i++)
	{
		uint32_t dw = in[i];
		uint32_t symbol = (dw > 0x000000FF) + (dw > 0x0000FFFF) + (dw > 0x00FFFFFF);
		key |= symbol << (i + i);
		*((uint32_t*)dataPtr) = dw;
		dataPtr += 1 + symbol;
	}
	memcpy(keyPtr, &key, ((count & 7) + 3) >> 2);

	return dataPtr - out;
}