shithub: libvpx

ref: 2f31a1644587e53bc7b5381a009e611de94a65f0
dir: /vp8/encoder/x86/quantize_sse4.c/

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/*
 *  Copyright (c) 2012 The WebM project authors. All Rights Reserved.
 *
 *  Use of this source code is governed by a BSD-style license
 *  that can be found in the LICENSE 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.
 */

#include <smmintrin.h> /* SSE4.1 */

#include "./vp8_rtcd.h"
#include "vp8/encoder/block.h"
#include "vp8/common/entropy.h" /* vp8_default_inv_zig_zag */

#define SELECT_EOB(i, z, x, y, q)         \
  do {                                    \
    short boost = *zbin_boost_ptr;        \
    short x_z = _mm_extract_epi16(x, z);  \
    short y_z = _mm_extract_epi16(y, z);  \
    int cmp = (x_z < boost) | (y_z == 0); \
    zbin_boost_ptr++;                     \
    if (cmp) break;                       \
    q = _mm_insert_epi16(q, y_z, z);      \
    eob = i;                              \
    zbin_boost_ptr = b->zrun_zbin_boost;  \
  } while (0)

void vp8_regular_quantize_b_sse4_1(BLOCK *b, BLOCKD *d) {
  char eob = 0;
  short *zbin_boost_ptr = b->zrun_zbin_boost;

  __m128i sz0, x0, sz1, x1, y0, y1, x_minus_zbin0, x_minus_zbin1, dqcoeff0,
      dqcoeff1;
  __m128i quant_shift0 = _mm_load_si128((__m128i *)(b->quant_shift));
  __m128i quant_shift1 = _mm_load_si128((__m128i *)(b->quant_shift + 8));
  __m128i z0 = _mm_load_si128((__m128i *)(b->coeff));
  __m128i z1 = _mm_load_si128((__m128i *)(b->coeff + 8));
  __m128i zbin_extra = _mm_cvtsi32_si128(b->zbin_extra);
  __m128i zbin0 = _mm_load_si128((__m128i *)(b->zbin));
  __m128i zbin1 = _mm_load_si128((__m128i *)(b->zbin + 8));
  __m128i round0 = _mm_load_si128((__m128i *)(b->round));
  __m128i round1 = _mm_load_si128((__m128i *)(b->round + 8));
  __m128i quant0 = _mm_load_si128((__m128i *)(b->quant));
  __m128i quant1 = _mm_load_si128((__m128i *)(b->quant + 8));
  __m128i dequant0 = _mm_load_si128((__m128i *)(d->dequant));
  __m128i dequant1 = _mm_load_si128((__m128i *)(d->dequant + 8));
  __m128i qcoeff0 = _mm_setzero_si128();
  __m128i qcoeff1 = _mm_setzero_si128();

  /* Duplicate to all lanes. */
  zbin_extra = _mm_shufflelo_epi16(zbin_extra, 0);
  zbin_extra = _mm_unpacklo_epi16(zbin_extra, zbin_extra);

  /* Sign of z: z >> 15 */
  sz0 = _mm_srai_epi16(z0, 15);
  sz1 = _mm_srai_epi16(z1, 15);

  /* x = abs(z): (z ^ sz) - sz */
  x0 = _mm_xor_si128(z0, sz0);
  x1 = _mm_xor_si128(z1, sz1);
  x0 = _mm_sub_epi16(x0, sz0);
  x1 = _mm_sub_epi16(x1, sz1);

  /* zbin[] + zbin_extra */
  zbin0 = _mm_add_epi16(zbin0, zbin_extra);
  zbin1 = _mm_add_epi16(zbin1, zbin_extra);

  /* In C x is compared to zbin where zbin = zbin[] + boost + extra. Rebalance
   * the equation because boost is the only value which can change:
   * x - (zbin[] + extra) >= boost */
  x_minus_zbin0 = _mm_sub_epi16(x0, zbin0);
  x_minus_zbin1 = _mm_sub_epi16(x1, zbin1);

  /* All the remaining calculations are valid whether they are done now with
   * simd or later inside the loop one at a time. */
  x0 = _mm_add_epi16(x0, round0);
  x1 = _mm_add_epi16(x1, round1);

  y0 = _mm_mulhi_epi16(x0, quant0);
  y1 = _mm_mulhi_epi16(x1, quant1);

  y0 = _mm_add_epi16(y0, x0);
  y1 = _mm_add_epi16(y1, x1);

  /* Instead of shifting each value independently we convert the scaling
   * factor with 1 << (16 - shift) so we can use multiply/return high half. */
  y0 = _mm_mulhi_epi16(y0, quant_shift0);
  y1 = _mm_mulhi_epi16(y1, quant_shift1);

  /* Return the sign: (y ^ sz) - sz */
  y0 = _mm_xor_si128(y0, sz0);
  y1 = _mm_xor_si128(y1, sz1);
  y0 = _mm_sub_epi16(y0, sz0);
  y1 = _mm_sub_epi16(y1, sz1);

  /* The loop gets unrolled anyway. Avoid the vp8_default_zig_zag1d lookup. */
  SELECT_EOB(1, 0, x_minus_zbin0, y0, qcoeff0);
  SELECT_EOB(2, 1, x_minus_zbin0, y0, qcoeff0);
  SELECT_EOB(3, 4, x_minus_zbin0, y0, qcoeff0);
  SELECT_EOB(4, 0, x_minus_zbin1, y1, qcoeff1);
  SELECT_EOB(5, 5, x_minus_zbin0, y0, qcoeff0);
  SELECT_EOB(6, 2, x_minus_zbin0, y0, qcoeff0);
  SELECT_EOB(7, 3, x_minus_zbin0, y0, qcoeff0);
  SELECT_EOB(8, 6, x_minus_zbin0, y0, qcoeff0);
  SELECT_EOB(9, 1, x_minus_zbin1, y1, qcoeff1);
  SELECT_EOB(10, 4, x_minus_zbin1, y1, qcoeff1);
  SELECT_EOB(11, 5, x_minus_zbin1, y1, qcoeff1);
  SELECT_EOB(12, 2, x_minus_zbin1, y1, qcoeff1);
  SELECT_EOB(13, 7, x_minus_zbin0, y0, qcoeff0);
  SELECT_EOB(14, 3, x_minus_zbin1, y1, qcoeff1);
  SELECT_EOB(15, 6, x_minus_zbin1, y1, qcoeff1);
  SELECT_EOB(16, 7, x_minus_zbin1, y1, qcoeff1);

  _mm_store_si128((__m128i *)(d->qcoeff), qcoeff0);
  _mm_store_si128((__m128i *)(d->qcoeff + 8), qcoeff1);

  dqcoeff0 = _mm_mullo_epi16(qcoeff0, dequant0);
  dqcoeff1 = _mm_mullo_epi16(qcoeff1, dequant1);

  _mm_store_si128((__m128i *)(d->dqcoeff), dqcoeff0);
  _mm_store_si128((__m128i *)(d->dqcoeff + 8), dqcoeff1);

  *d->eob = eob;
}