// Copyright 2011 Google Inc. All Rights Reserved.

//

// Use of this source code is governed by a BSD-style license

// that can be found in the COPYING file in the root of the source

// tree. An additional intellectual property rights grant can be found

// in the file PATENTS. All contributing project authors may

// be found in the AUTHORS file in the root of the source tree.

// -----------------------------------------------------------------------------

//

// SSE41 version of YUV to RGB upsampling functions.

//

// Author: somnath@google.com (Somnath Banerjee)

#include "src/dsp/dsp.h"

#if defined(WEBP_USE_SSE41)

#include <assert.h>

#include <smmintrin.h>

#include <string.h>

#include "src/dsp/yuv.h"

#ifdef FANCY_UPSAMPLING

#if !defined(WEBP_REDUCE_CSP)

// We compute (9*a + 3*b + 3*c + d + 8) / 16 as follows

// u = (9*a + 3*b + 3*c + d + 8) / 16

// = (a + (a + 3*b + 3*c + d) / 8 + 1) / 2

// = (a + m + 1) / 2

// where m = (a + 3*b + 3*c + d) / 8

// = ((a + b + c + d) / 2 + b + c) / 4

//

// Let's say k = (a + b + c + d) / 4.

// We can compute k as

// k = (s + t + 1) / 2 - ((a^d) | (b^c) | (s^t)) & 1

// where s = (a + d + 1) / 2 and t = (b + c + 1) / 2

//

// Then m can be written as

// m = (k + t + 1) / 2 - (((b^c) & (s^t)) | (k^t)) & 1

// Computes out = (k + in + 1) / 2 - ((ij & (s^t)) | (k^in)) & 1

#define GET_M(ij, in, out) do { \

const __m128i tmp0 = _mm_avg_epu8(k, (in)); /* (k + in + 1) / 2 */ \

const __m128i tmp1 = _mm_and_si128((ij), st); /* (ij) & (s^t) */ \

const __m128i tmp2 = _mm_xor_si128(k, (in)); /* (k^in) */ \

const __m128i tmp3 = _mm_or_si128(tmp1, tmp2); /* ((ij) & (s^t)) | (k^in) */\

const __m128i tmp4 = _mm_and_si128(tmp3, one); /* & 1 -> lsb_correction */ \

(out) = _mm_sub_epi8(tmp0, tmp4); /* (k + in + 1) / 2 - lsb_correction */ \

} while (0)

// pack and store two alternating pixel rows

#define PACK_AND_STORE(a, b, da, db, out) do { \

const __m128i t_a = _mm_avg_epu8(a, da); /* (9a + 3b + 3c + d + 8) / 16 */ \

const __m128i t_b = _mm_avg_epu8(b, db); /* (3a + 9b + c + 3d + 8) / 16 */ \

const __m128i t_1 = _mm_unpacklo_epi8(t_a, t_b); \

const __m128i t_2 = _mm_unpackhi_epi8(t_a, t_b); \

_mm_store_si128(((__m128i*)(out)) + 0, t_1); \

_mm_store_si128(((__m128i*)(out)) + 1, t_2); \

} while (0)

// Loads 17 pixels each from rows r1 and r2 and generates 32 pixels.

#define UPSAMPLE_32PIXELS(r1, r2, out) { \

const __m128i one = _mm_set1_epi8(1); \

const __m128i a = _mm_loadu_si128((const __m128i*)&(r1)[0]); \

const __m128i b = _mm_loadu_si128((const __m128i*)&(r1)[1]); \

const __m128i c = _mm_loadu_si128((const __m128i*)&(r2)[0]); \

const __m128i d = _mm_loadu_si128((const __m128i*)&(r2)[1]); \

\

const __m128i s = _mm_avg_epu8(a, d); /* s = (a + d + 1) / 2 */ \

const __m128i t = _mm_avg_epu8(b, c); /* t = (b + c + 1) / 2 */ \

const __m128i st = _mm_xor_si128(s, t); /* st = s^t */ \

\

const __m128i ad = _mm_xor_si128(a, d); /* ad = a^d */ \

const __m128i bc = _mm_xor_si128(b, c); /* bc = b^c */ \

\

const __m128i t1 = _mm_or_si128(ad, bc); /* (a^d) | (b^c) */ \

const __m128i t2 = _mm_or_si128(t1, st); /* (a^d) | (b^c) | (s^t) */ \

const __m128i t3 = _mm_and_si128(t2, one); /* (a^d) | (b^c) | (s^t) & 1 */ \

const __m128i t4 = _mm_avg_epu8(s, t); \

const __m128i k = _mm_sub_epi8(t4, t3); /* k = (a + b + c + d) / 4 */ \

__m128i diag1, diag2; \

\

GET_M(bc, t, diag1); /* diag1 = (a + 3b + 3c + d) / 8 */ \

GET_M(ad, s, diag2); /* diag2 = (3a + b + c + 3d) / 8 */ \

\

/* pack the alternate pixels */ \

PACK_AND_STORE(a, b, diag1, diag2, (out) + 0); /* store top */ \

PACK_AND_STORE(c, d, diag2, diag1, (out) + 2 * 32); /* store bottom */ \

}

// Turn the macro into a function for reducing code-size when non-critical

static void Upsample32Pixels_SSE41(const uint8_t r1[], const uint8_t r2[],

uint8_t* const out) {

UPSAMPLE_32PIXELS(r1, r2, out);

}

#define UPSAMPLE_LAST_BLOCK(tb, bb, num_pixels, out) { \

uint8_t r1[17], r2[17]; \

memcpy(r1, (tb), (num_pixels)); \

memcpy(r2, (bb), (num_pixels)); \

/* replicate last byte */ \

memset(r1 + (num_pixels), r1[(num_pixels) - 1], 17 - (num_pixels)); \

memset(r2 + (num_pixels), r2[(num_pixels) - 1], 17 - (num_pixels)); \

/* using the shared function instead of the macro saves ~3k code size */ \

Upsample32Pixels_SSE41(r1, r2, out); \

}

#define CONVERT2RGB_32(FUNC, XSTEP, top_y, bottom_y, \

top_dst, bottom_dst, cur_x) do { \

FUNC##32_SSE41((top_y) + (cur_x), r_u, r_v, (top_dst) + (cur_x) * (XSTEP)); \

if ((bottom_y) != NULL) { \

FUNC##32_SSE41((bottom_y) + (cur_x), r_u + 64, r_v + 64, \

(bottom_dst) + (cur_x) * (XSTEP)); \

} \

} while (0)

#define SSE4_UPSAMPLE_FUNC(FUNC_NAME, FUNC, XSTEP) \

static void FUNC_NAME(const uint8_t* top_y, const uint8_t* bottom_y, \

const uint8_t* top_u, const uint8_t* top_v, \

const uint8_t* cur_u, const uint8_t* cur_v, \

uint8_t* top_dst, uint8_t* bottom_dst, int len) { \

int uv_pos, pos; \

/* 16byte-aligned array to cache reconstructed u and v */ \

uint8_t uv_buf[14 * 32 + 15] = { 0 }; \

uint8_t* const r_u = (uint8_t*)((uintptr_t)(uv_buf + 15) & ~15); \

uint8_t* const r_v = r_u + 32; \

\

assert(top_y != NULL); \

{ /* Treat the first pixel in regular way */ \

const int u_diag = ((top_u[0] + cur_u[0]) >> 1) + 1; \

const int v_diag = ((top_v[0] + cur_v[0]) >> 1) + 1; \

const int u0_t = (top_u[0] + u_diag) >> 1; \

const int v0_t = (top_v[0] + v_diag) >> 1; \

FUNC(top_y[0], u0_t, v0_t, top_dst); \

if (bottom_y != NULL) { \

const int u0_b = (cur_u[0] + u_diag) >> 1; \

const int v0_b = (cur_v[0] + v_diag) >> 1; \

FUNC(bottom_y[0], u0_b, v0_b, bottom_dst); \

} \

} \

/* For UPSAMPLE_32PIXELS, 17 u/v values must be read-able for each block */ \

for (pos = 1, uv_pos = 0; pos + 32 + 1 <= len; pos += 32, uv_pos += 16) { \

UPSAMPLE_32PIXELS(top_u + uv_pos, cur_u + uv_pos, r_u); \

UPSAMPLE_32PIXELS(top_v + uv_pos, cur_v + uv_pos, r_v); \

CONVERT2RGB_32(FUNC, XSTEP, top_y, bottom_y, top_dst, bottom_dst, pos); \

} \

if (len > 1) { \

const int left_over = ((len + 1) >> 1) - (pos >> 1); \

uint8_t* const tmp_top_dst = r_u + 4 * 32; \

uint8_t* const tmp_bottom_dst = tmp_top_dst + 4 * 32; \

uint8_t* const tmp_top = tmp_bottom_dst + 4 * 32; \

uint8_t* const tmp_bottom = (bottom_y == NULL) ? NULL : tmp_top + 32; \

assert(left_over > 0); \

UPSAMPLE_LAST_BLOCK(top_u + uv_pos, cur_u + uv_pos, left_over, r_u); \

UPSAMPLE_LAST_BLOCK(top_v + uv_pos, cur_v + uv_pos, left_over, r_v); \

memcpy(tmp_top, top_y + pos, len - pos); \

if (bottom_y != NULL) memcpy(tmp_bottom, bottom_y + pos, len - pos); \

CONVERT2RGB_32(FUNC, XSTEP, tmp_top, tmp_bottom, tmp_top_dst, \

tmp_bottom_dst, 0); \

memcpy(top_dst + pos * (XSTEP), tmp_top_dst, (len - pos) * (XSTEP)); \

if (bottom_y != NULL) { \

memcpy(bottom_dst + pos * (XSTEP), tmp_bottom_dst, \

(len - pos) * (XSTEP)); \

} \

} \

}

// SSE4 variants of the fancy upsampler.

SSE4_UPSAMPLE_FUNC(UpsampleRgbLinePair_SSE41, VP8YuvToRgb, 3)

SSE4_UPSAMPLE_FUNC(UpsampleBgrLinePair_SSE41, VP8YuvToBgr, 3)

#undef GET_M

#undef PACK_AND_STORE

#undef UPSAMPLE_32PIXELS

#undef UPSAMPLE_LAST_BLOCK

#undef CONVERT2RGB

#undef CONVERT2RGB_32

#undef SSE4_UPSAMPLE_FUNC

#endif // WEBP_REDUCE_CSP

//------------------------------------------------------------------------------

// Entry point

extern WebPUpsampleLinePairFunc WebPUpsamplers[/* MODE_LAST */];

extern void WebPInitUpsamplersSSE41(void);

WEBP_TSAN_IGNORE_FUNCTION void WebPInitUpsamplersSSE41(void) {

#if !defined(WEBP_REDUCE_CSP)

WebPUpsamplers[MODE_RGB] = UpsampleRgbLinePair_SSE41;

WebPUpsamplers[MODE_BGR] = UpsampleBgrLinePair_SSE41;

#endif // WEBP_REDUCE_CSP

}

#endif // FANCY_UPSAMPLING

//------------------------------------------------------------------------------

extern WebPYUV444Converter WebPYUV444Converters[/* MODE_LAST */];

extern void WebPInitYUV444ConvertersSSE41(void);

#define YUV444_FUNC(FUNC_NAME, CALL, CALL_C, XSTEP) \

extern void CALL_C(const uint8_t* y, const uint8_t* u, const uint8_t* v, \

uint8_t* dst, int len); \

static void FUNC_NAME(const uint8_t* y, const uint8_t* u, const uint8_t* v, \

uint8_t* dst, int len) { \

int i; \

const int max_len = len & ~31; \

for (i = 0; i < max_len; i += 32) { \

CALL(y + i, u + i, v + i, dst + i * (XSTEP)); \

} \

if (i < len) { /* C-fallback */ \

CALL_C(y + i, u + i, v + i, dst + i * (XSTEP), len - i); \

} \

}

#if !defined(WEBP_REDUCE_CSP)

YUV444_FUNC(Yuv444ToRgb_SSE41, VP8YuvToRgb32_SSE41, WebPYuv444ToRgb_C, 3);

YUV444_FUNC(Yuv444ToBgr_SSE41, VP8YuvToBgr32_SSE41, WebPYuv444ToBgr_C, 3);

#endif // WEBP_REDUCE_CSP

WEBP_TSAN_IGNORE_FUNCTION void WebPInitYUV444ConvertersSSE41(void) {

#if !defined(WEBP_REDUCE_CSP)

WebPYUV444Converters[MODE_RGB] = Yuv444ToRgb_SSE41;

WebPYUV444Converters[MODE_BGR] = Yuv444ToBgr_SSE41;

#endif // WEBP_REDUCE_CSP

}

#else

WEBP_DSP_INIT_STUB(WebPInitYUV444ConvertersSSE41)

#endif // WEBP_USE_SSE41

#if !(defined(FANCY_UPSAMPLING) && defined(WEBP_USE_SSE41))

WEBP_DSP_INIT_STUB(WebPInitUpsamplersSSE41)

#endif