xref: /aosp_15_r20/external/libvpx/vp8/encoder/x86/vp8_quantize_ssse3.c (revision fb1b10ab9aebc7c7068eedab379b749d7e3900be)
1 /*
2  *  Copyright (c) 2012 The WebM project authors. All Rights Reserved.
3  *
4  *  Use of this source code is governed by a BSD-style license
5  *  that can be found in the LICENSE file in the root of the source
6  *  tree. An additional intellectual property rights grant can be found
7  *  in the file PATENTS.  All contributing project authors may
8  *  be found in the AUTHORS file in the root of the source tree.
9  */
10 
11 #include <tmmintrin.h> /* SSSE3 */
12 
13 #include "./vp8_rtcd.h"
14 #include "vp8/encoder/block.h"
15 #include "vpx_ports/bitops.h" /* get_msb */
16 
vp8_fast_quantize_b_ssse3(BLOCK * b,BLOCKD * d)17 void vp8_fast_quantize_b_ssse3(BLOCK *b, BLOCKD *d) {
18   int eob, mask;
19 
20   __m128i z0 = _mm_load_si128((__m128i *)(b->coeff));
21   __m128i z1 = _mm_load_si128((__m128i *)(b->coeff + 8));
22   __m128i round0 = _mm_load_si128((__m128i *)(b->round));
23   __m128i round1 = _mm_load_si128((__m128i *)(b->round + 8));
24   __m128i quant_fast0 = _mm_load_si128((__m128i *)(b->quant_fast));
25   __m128i quant_fast1 = _mm_load_si128((__m128i *)(b->quant_fast + 8));
26   __m128i dequant0 = _mm_load_si128((__m128i *)(d->dequant));
27   __m128i dequant1 = _mm_load_si128((__m128i *)(d->dequant + 8));
28 
29   __m128i sz0, sz1, x, x0, x1, y0, y1, zeros, abs0, abs1;
30 
31   DECLARE_ALIGNED(16, const uint8_t,
32                   pshufb_zig_zag_mask[16]) = { 0, 1,  4,  8,  5, 2,  3,  6,
33                                                9, 12, 13, 10, 7, 11, 14, 15 };
34   __m128i zig_zag = _mm_load_si128((const __m128i *)pshufb_zig_zag_mask);
35 
36   /* sign of z: z >> 15 */
37   sz0 = _mm_srai_epi16(z0, 15);
38   sz1 = _mm_srai_epi16(z1, 15);
39 
40   /* x = abs(z) */
41   x0 = _mm_abs_epi16(z0);
42   x1 = _mm_abs_epi16(z1);
43 
44   /* x += round */
45   x0 = _mm_add_epi16(x0, round0);
46   x1 = _mm_add_epi16(x1, round1);
47 
48   /* y = (x * quant) >> 16 */
49   y0 = _mm_mulhi_epi16(x0, quant_fast0);
50   y1 = _mm_mulhi_epi16(x1, quant_fast1);
51 
52   /* ASM saves Y for EOB */
53   /* I think we can ignore that because adding the sign doesn't change anything
54    * and multiplying 0 by dequant is OK as well */
55   abs0 = y0;
56   abs1 = y1;
57 
58   /* Restore the sign bit. */
59   y0 = _mm_xor_si128(y0, sz0);
60   y1 = _mm_xor_si128(y1, sz1);
61   x0 = _mm_sub_epi16(y0, sz0);
62   x1 = _mm_sub_epi16(y1, sz1);
63 
64   /* qcoeff = x */
65   _mm_store_si128((__m128i *)(d->qcoeff), x0);
66   _mm_store_si128((__m128i *)(d->qcoeff + 8), x1);
67 
68   /* x * dequant */
69   x0 = _mm_mullo_epi16(x0, dequant0);
70   x1 = _mm_mullo_epi16(x1, dequant1);
71 
72   /* dqcoeff = x * dequant */
73   _mm_store_si128((__m128i *)(d->dqcoeff), x0);
74   _mm_store_si128((__m128i *)(d->dqcoeff + 8), x1);
75 
76   zeros = _mm_setzero_si128();
77 
78   x0 = _mm_cmpgt_epi16(abs0, zeros);
79   x1 = _mm_cmpgt_epi16(abs1, zeros);
80 
81   x = _mm_packs_epi16(x0, x1);
82 
83   x = _mm_shuffle_epi8(x, zig_zag);
84 
85   mask = _mm_movemask_epi8(x);
86 
87   /* x2 is needed to increase the result from non-zero masks by 1,
88    * +1 is needed to mask undefined behavior for a null argument,
89    * the result of get_msb(1) is 0 */
90   eob = get_msb(mask * 2 + 1);
91 
92   *d->eob = eob;
93 }
94