374 lines
14 KiB
C
374 lines
14 KiB
C
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// Copyright 2015 Google Inc. All Rights Reserved.
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//
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// Use of this source code is governed by a BSD-style license
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// that can be found in the COPYING file in the root of the source
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// tree. An additional intellectual property rights grant can be found
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// in the file PATENTS. All contributing project authors may
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// be found in the AUTHORS file in the root of the source tree.
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// -----------------------------------------------------------------------------
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//
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// SSE2 Rescaling functions
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//
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// Author: Skal (pascal.massimino@gmail.com)
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#include "./dsp.h"
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#if defined(WEBP_USE_SSE2)
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#include <emmintrin.h>
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#include <assert.h>
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#include "../utils/rescaler.h"
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//------------------------------------------------------------------------------
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// Implementations of critical functions ImportRow / ExportRow
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#define ROUNDER (WEBP_RESCALER_ONE >> 1)
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#define MULT_FIX(x, y) (((uint64_t)(x) * (y) + ROUNDER) >> WEBP_RESCALER_RFIX)
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// input: 8 bytes ABCDEFGH -> output: A0E0B0F0C0G0D0H0
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static void LoadTwoPixels(const uint8_t* const src, __m128i* out) {
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const __m128i zero = _mm_setzero_si128();
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const __m128i A = _mm_loadl_epi64((const __m128i*)(src)); // ABCDEFGH
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const __m128i B = _mm_unpacklo_epi8(A, zero); // A0B0C0D0E0F0G0H0
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const __m128i C = _mm_srli_si128(B, 8); // E0F0G0H0
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*out = _mm_unpacklo_epi16(B, C);
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}
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// input: 8 bytes ABCDEFGH -> output: A0B0C0D0E0F0G0H0
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static void LoadHeightPixels(const uint8_t* const src, __m128i* out) {
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const __m128i zero = _mm_setzero_si128();
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const __m128i A = _mm_loadl_epi64((const __m128i*)(src)); // ABCDEFGH
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*out = _mm_unpacklo_epi8(A, zero);
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}
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static void RescalerImportRowExpandSSE2(WebPRescaler* const wrk,
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const uint8_t* src) {
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rescaler_t* frow = wrk->frow;
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const rescaler_t* const frow_end = frow + wrk->dst_width * wrk->num_channels;
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const int x_add = wrk->x_add;
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int accum = x_add;
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__m128i cur_pixels;
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assert(!WebPRescalerInputDone(wrk));
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assert(wrk->x_expand);
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if (wrk->num_channels == 4) {
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if (wrk->src_width < 2) {
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WebPRescalerImportRowExpandC(wrk, src);
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return;
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}
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LoadTwoPixels(src, &cur_pixels);
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src += 4;
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while (1) {
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const __m128i mult = _mm_set1_epi32(((x_add - accum) << 16) | accum);
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const __m128i out = _mm_madd_epi16(cur_pixels, mult);
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_mm_storeu_si128((__m128i*)frow, out);
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frow += 4;
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if (frow >= frow_end) break;
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accum -= wrk->x_sub;
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if (accum < 0) {
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LoadTwoPixels(src, &cur_pixels);
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src += 4;
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accum += x_add;
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}
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}
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} else {
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int left;
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const uint8_t* const src_limit = src + wrk->src_width - 8;
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if (wrk->src_width < 8) {
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WebPRescalerImportRowExpandC(wrk, src);
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return;
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}
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LoadHeightPixels(src, &cur_pixels);
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src += 7;
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left = 7;
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while (1) {
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const __m128i mult = _mm_cvtsi32_si128(((x_add - accum) << 16) | accum);
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const __m128i out = _mm_madd_epi16(cur_pixels, mult);
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*(uint32_t*)frow = _mm_cvtsi128_si32(out);
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frow += 1;
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if (frow >= frow_end) break;
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accum -= wrk->x_sub;
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if (accum < 0) {
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if (--left) {
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cur_pixels = _mm_srli_si128(cur_pixels, 2);
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} else if (src <= src_limit) {
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LoadHeightPixels(src, &cur_pixels);
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src += 7;
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left = 7;
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} else { // tail
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cur_pixels = _mm_srli_si128(cur_pixels, 2);
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cur_pixels = _mm_insert_epi16(cur_pixels, src[1], 1);
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src += 1;
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left = 1;
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}
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accum += x_add;
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}
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}
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}
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assert(accum == 0);
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}
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static void RescalerImportRowShrinkSSE2(WebPRescaler* const wrk,
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const uint8_t* src) {
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const int x_sub = wrk->x_sub;
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int accum = 0;
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const __m128i zero = _mm_setzero_si128();
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const __m128i mult0 = _mm_set1_epi16(x_sub);
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const __m128i mult1 = _mm_set1_epi32(wrk->fx_scale);
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const __m128i rounder = _mm_set_epi32(0, ROUNDER, 0, ROUNDER);
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__m128i sum = zero;
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rescaler_t* frow = wrk->frow;
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const rescaler_t* const frow_end = wrk->frow + 4 * wrk->dst_width;
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if (wrk->num_channels != 4 || wrk->x_add > (x_sub << 7)) {
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WebPRescalerImportRowShrinkC(wrk, src);
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return;
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}
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assert(!WebPRescalerInputDone(wrk));
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assert(!wrk->x_expand);
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for (; frow < frow_end; frow += 4) {
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__m128i base = zero;
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accum += wrk->x_add;
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while (accum > 0) {
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const __m128i A = _mm_cvtsi32_si128(*(int*)src);
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src += 4;
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base = _mm_unpacklo_epi8(A, zero);
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// To avoid overflow, we need: base * x_add / x_sub < 32768
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// => x_add < x_sub << 7. That's a 1/128 reduction ratio limit.
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sum = _mm_add_epi16(sum, base);
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accum -= x_sub;
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}
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{ // Emit next horizontal pixel.
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const __m128i mult = _mm_set1_epi16(-accum);
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const __m128i frac0 = _mm_mullo_epi16(base, mult); // 16b x 16b -> 32b
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const __m128i frac1 = _mm_mulhi_epu16(base, mult);
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const __m128i frac = _mm_unpacklo_epi16(frac0, frac1); // frac is 32b
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const __m128i A0 = _mm_mullo_epi16(sum, mult0);
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const __m128i A1 = _mm_mulhi_epu16(sum, mult0);
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const __m128i B0 = _mm_unpacklo_epi16(A0, A1); // sum * x_sub
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const __m128i frow_out = _mm_sub_epi32(B0, frac); // sum * x_sub - frac
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const __m128i D0 = _mm_srli_epi64(frac, 32);
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const __m128i D1 = _mm_mul_epu32(frac, mult1); // 32b x 16b -> 64b
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const __m128i D2 = _mm_mul_epu32(D0, mult1);
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const __m128i E1 = _mm_add_epi64(D1, rounder);
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const __m128i E2 = _mm_add_epi64(D2, rounder);
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const __m128i F1 = _mm_shuffle_epi32(E1, 1 | (3 << 2));
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const __m128i F2 = _mm_shuffle_epi32(E2, 1 | (3 << 2));
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const __m128i G = _mm_unpacklo_epi32(F1, F2);
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sum = _mm_packs_epi32(G, zero);
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_mm_storeu_si128((__m128i*)frow, frow_out);
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}
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}
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assert(accum == 0);
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}
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//------------------------------------------------------------------------------
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// Row export
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// load *src as epi64, multiply by mult and store result in [out0 ... out3]
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static WEBP_INLINE void LoadDispatchAndMult(const rescaler_t* const src,
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const __m128i* const mult,
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__m128i* const out0,
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__m128i* const out1,
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__m128i* const out2,
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__m128i* const out3) {
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const __m128i A0 = _mm_loadu_si128((const __m128i*)(src + 0));
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const __m128i A1 = _mm_loadu_si128((const __m128i*)(src + 4));
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const __m128i A2 = _mm_srli_epi64(A0, 32);
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const __m128i A3 = _mm_srli_epi64(A1, 32);
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if (mult != NULL) {
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*out0 = _mm_mul_epu32(A0, *mult);
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*out1 = _mm_mul_epu32(A1, *mult);
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*out2 = _mm_mul_epu32(A2, *mult);
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*out3 = _mm_mul_epu32(A3, *mult);
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} else {
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*out0 = A0;
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*out1 = A1;
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*out2 = A2;
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*out3 = A3;
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}
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}
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static WEBP_INLINE void ProcessRow(const __m128i* const A0,
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const __m128i* const A1,
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const __m128i* const A2,
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const __m128i* const A3,
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const __m128i* const mult,
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uint8_t* const dst) {
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const __m128i rounder = _mm_set_epi32(0, ROUNDER, 0, ROUNDER);
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const __m128i mask = _mm_set_epi32(0xffffffffu, 0, 0xffffffffu, 0);
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const __m128i B0 = _mm_mul_epu32(*A0, *mult);
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const __m128i B1 = _mm_mul_epu32(*A1, *mult);
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const __m128i B2 = _mm_mul_epu32(*A2, *mult);
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const __m128i B3 = _mm_mul_epu32(*A3, *mult);
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const __m128i C0 = _mm_add_epi64(B0, rounder);
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const __m128i C1 = _mm_add_epi64(B1, rounder);
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const __m128i C2 = _mm_add_epi64(B2, rounder);
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const __m128i C3 = _mm_add_epi64(B3, rounder);
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const __m128i D0 = _mm_srli_epi64(C0, WEBP_RESCALER_RFIX);
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const __m128i D1 = _mm_srli_epi64(C1, WEBP_RESCALER_RFIX);
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#if (WEBP_RESCALER_FIX < 32)
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const __m128i D2 =
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_mm_and_si128(_mm_slli_epi64(C2, 32 - WEBP_RESCALER_RFIX), mask);
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const __m128i D3 =
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_mm_and_si128(_mm_slli_epi64(C3, 32 - WEBP_RESCALER_RFIX), mask);
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#else
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const __m128i D2 = _mm_and_si128(C2, mask);
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const __m128i D3 = _mm_and_si128(C3, mask);
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#endif
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const __m128i E0 = _mm_or_si128(D0, D2);
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const __m128i E1 = _mm_or_si128(D1, D3);
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const __m128i F = _mm_packs_epi32(E0, E1);
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const __m128i G = _mm_packus_epi16(F, F);
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_mm_storel_epi64((__m128i*)dst, G);
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}
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static void RescalerExportRowExpandSSE2(WebPRescaler* const wrk) {
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int x_out;
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uint8_t* const dst = wrk->dst;
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rescaler_t* const irow = wrk->irow;
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const int x_out_max = wrk->dst_width * wrk->num_channels;
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const rescaler_t* const frow = wrk->frow;
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const __m128i mult = _mm_set_epi32(0, wrk->fy_scale, 0, wrk->fy_scale);
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assert(!WebPRescalerOutputDone(wrk));
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assert(wrk->y_accum <= 0 && wrk->y_sub + wrk->y_accum >= 0);
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assert(wrk->y_expand);
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if (wrk->y_accum == 0) {
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for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) {
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__m128i A0, A1, A2, A3;
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LoadDispatchAndMult(frow + x_out, NULL, &A0, &A1, &A2, &A3);
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ProcessRow(&A0, &A1, &A2, &A3, &mult, dst + x_out);
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}
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for (; x_out < x_out_max; ++x_out) {
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const uint32_t J = frow[x_out];
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const int v = (int)MULT_FIX(J, wrk->fy_scale);
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assert(v >= 0 && v <= 255);
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dst[x_out] = v;
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}
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} else {
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const uint32_t B = WEBP_RESCALER_FRAC(-wrk->y_accum, wrk->y_sub);
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const uint32_t A = (uint32_t)(WEBP_RESCALER_ONE - B);
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const __m128i mA = _mm_set_epi32(0, A, 0, A);
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const __m128i mB = _mm_set_epi32(0, B, 0, B);
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const __m128i rounder = _mm_set_epi32(0, ROUNDER, 0, ROUNDER);
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for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) {
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__m128i A0, A1, A2, A3, B0, B1, B2, B3;
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LoadDispatchAndMult(frow + x_out, &mA, &A0, &A1, &A2, &A3);
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LoadDispatchAndMult(irow + x_out, &mB, &B0, &B1, &B2, &B3);
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{
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const __m128i C0 = _mm_add_epi64(A0, B0);
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const __m128i C1 = _mm_add_epi64(A1, B1);
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const __m128i C2 = _mm_add_epi64(A2, B2);
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const __m128i C3 = _mm_add_epi64(A3, B3);
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const __m128i D0 = _mm_add_epi64(C0, rounder);
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const __m128i D1 = _mm_add_epi64(C1, rounder);
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const __m128i D2 = _mm_add_epi64(C2, rounder);
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const __m128i D3 = _mm_add_epi64(C3, rounder);
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const __m128i E0 = _mm_srli_epi64(D0, WEBP_RESCALER_RFIX);
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const __m128i E1 = _mm_srli_epi64(D1, WEBP_RESCALER_RFIX);
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const __m128i E2 = _mm_srli_epi64(D2, WEBP_RESCALER_RFIX);
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const __m128i E3 = _mm_srli_epi64(D3, WEBP_RESCALER_RFIX);
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ProcessRow(&E0, &E1, &E2, &E3, &mult, dst + x_out);
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}
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}
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for (; x_out < x_out_max; ++x_out) {
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const uint64_t I = (uint64_t)A * frow[x_out]
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+ (uint64_t)B * irow[x_out];
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const uint32_t J = (uint32_t)((I + ROUNDER) >> WEBP_RESCALER_RFIX);
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const int v = (int)MULT_FIX(J, wrk->fy_scale);
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assert(v >= 0 && v <= 255);
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dst[x_out] = v;
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}
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}
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}
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static void RescalerExportRowShrinkSSE2(WebPRescaler* const wrk) {
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int x_out;
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uint8_t* const dst = wrk->dst;
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rescaler_t* const irow = wrk->irow;
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const int x_out_max = wrk->dst_width * wrk->num_channels;
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const rescaler_t* const frow = wrk->frow;
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||
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const uint32_t yscale = wrk->fy_scale * (-wrk->y_accum);
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assert(!WebPRescalerOutputDone(wrk));
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|
assert(wrk->y_accum <= 0);
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||
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|
assert(!wrk->y_expand);
|
||
|
|
if (yscale) {
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const int scale_xy = wrk->fxy_scale;
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const __m128i mult_xy = _mm_set_epi32(0, scale_xy, 0, scale_xy);
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const __m128i mult_y = _mm_set_epi32(0, yscale, 0, yscale);
|
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const __m128i rounder = _mm_set_epi32(0, ROUNDER, 0, ROUNDER);
|
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|
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for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) {
|
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|
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__m128i A0, A1, A2, A3, B0, B1, B2, B3;
|
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|
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LoadDispatchAndMult(irow + x_out, NULL, &A0, &A1, &A2, &A3);
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LoadDispatchAndMult(frow + x_out, &mult_y, &B0, &B1, &B2, &B3);
|
||
|
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{
|
||
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const __m128i C0 = _mm_add_epi64(B0, rounder);
|
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|
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const __m128i C1 = _mm_add_epi64(B1, rounder);
|
||
|
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const __m128i C2 = _mm_add_epi64(B2, rounder);
|
||
|
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const __m128i C3 = _mm_add_epi64(B3, rounder);
|
||
|
|
const __m128i D0 = _mm_srli_epi64(C0, WEBP_RESCALER_RFIX); // = frac
|
||
|
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const __m128i D1 = _mm_srli_epi64(C1, WEBP_RESCALER_RFIX);
|
||
|
|
const __m128i D2 = _mm_srli_epi64(C2, WEBP_RESCALER_RFIX);
|
||
|
|
const __m128i D3 = _mm_srli_epi64(C3, WEBP_RESCALER_RFIX);
|
||
|
|
const __m128i E0 = _mm_sub_epi64(A0, D0); // irow[x] - frac
|
||
|
|
const __m128i E1 = _mm_sub_epi64(A1, D1);
|
||
|
|
const __m128i E2 = _mm_sub_epi64(A2, D2);
|
||
|
|
const __m128i E3 = _mm_sub_epi64(A3, D3);
|
||
|
|
const __m128i F2 = _mm_slli_epi64(D2, 32);
|
||
|
|
const __m128i F3 = _mm_slli_epi64(D3, 32);
|
||
|
|
const __m128i G0 = _mm_or_si128(D0, F2);
|
||
|
|
const __m128i G1 = _mm_or_si128(D1, F3);
|
||
|
|
_mm_storeu_si128((__m128i*)(irow + x_out + 0), G0);
|
||
|
|
_mm_storeu_si128((__m128i*)(irow + x_out + 4), G1);
|
||
|
|
ProcessRow(&E0, &E1, &E2, &E3, &mult_xy, dst + x_out);
|
||
|
|
}
|
||
|
|
}
|
||
|
|
for (; x_out < x_out_max; ++x_out) {
|
||
|
|
const uint32_t frac = (int)MULT_FIX(frow[x_out], yscale);
|
||
|
|
const int v = (int)MULT_FIX(irow[x_out] - frac, wrk->fxy_scale);
|
||
|
|
assert(v >= 0 && v <= 255);
|
||
|
|
dst[x_out] = v;
|
||
|
|
irow[x_out] = frac; // new fractional start
|
||
|
|
}
|
||
|
|
} else {
|
||
|
|
const uint32_t scale = wrk->fxy_scale;
|
||
|
|
const __m128i mult = _mm_set_epi32(0, scale, 0, scale);
|
||
|
|
const __m128i zero = _mm_setzero_si128();
|
||
|
|
for (x_out = 0; x_out + 8 <= x_out_max; x_out += 8) {
|
||
|
|
__m128i A0, A1, A2, A3;
|
||
|
|
LoadDispatchAndMult(irow + x_out, NULL, &A0, &A1, &A2, &A3);
|
||
|
|
_mm_storeu_si128((__m128i*)(irow + x_out + 0), zero);
|
||
|
|
_mm_storeu_si128((__m128i*)(irow + x_out + 4), zero);
|
||
|
|
ProcessRow(&A0, &A1, &A2, &A3, &mult, dst + x_out);
|
||
|
|
}
|
||
|
|
for (; x_out < x_out_max; ++x_out) {
|
||
|
|
const int v = (int)MULT_FIX(irow[x_out], scale);
|
||
|
|
assert(v >= 0 && v <= 255);
|
||
|
|
dst[x_out] = v;
|
||
|
|
irow[x_out] = 0;
|
||
|
|
}
|
||
|
|
}
|
||
|
|
}
|
||
|
|
|
||
|
|
#undef MULT_FIX
|
||
|
|
#undef ROUNDER
|
||
|
|
|
||
|
|
//------------------------------------------------------------------------------
|
||
|
|
|
||
|
|
extern void WebPRescalerDspInitSSE2(void);
|
||
|
|
|
||
|
|
WEBP_TSAN_IGNORE_FUNCTION void WebPRescalerDspInitSSE2(void) {
|
||
|
|
WebPRescalerImportRowExpand = RescalerImportRowExpandSSE2;
|
||
|
|
WebPRescalerImportRowShrink = RescalerImportRowShrinkSSE2;
|
||
|
|
WebPRescalerExportRowExpand = RescalerExportRowExpandSSE2;
|
||
|
|
WebPRescalerExportRowShrink = RescalerExportRowShrinkSSE2;
|
||
|
|
}
|
||
|
|
|
||
|
|
#else // !WEBP_USE_SSE2
|
||
|
|
|
||
|
|
WEBP_DSP_INIT_STUB(WebPRescalerDspInitSSE2)
|
||
|
|
|
||
|
|
#endif // WEBP_USE_SSE2
|