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mpegaudiodec_altivec.c
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1 /*
2  * Altivec optimized MP3 decoding functions
3  * Copyright (c) 2010 Vitor Sessak
4  *
5  * This file is part of FFmpeg.
6  *
7  * FFmpeg is free software; you can redistribute it and/or
8  * modify it under the terms of the GNU Lesser General Public
9  * License as published by the Free Software Foundation; either
10  * version 2.1 of the License, or (at your option) any later version.
11  *
12  * FFmpeg is distributed in the hope that it will be useful,
13  * but WITHOUT ANY WARRANTY; without even the implied warranty of
14  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
15  * Lesser General Public License for more details.
16  *
17  * You should have received a copy of the GNU Lesser General Public
18  * License along with FFmpeg; if not, write to the Free Software
19  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
20  */
21 
22 #include "dsputil_altivec.h"
23 #include "libavutil/attributes.h"
24 #include "libavutil/internal.h"
27 
28 #define MACS(rt, ra, rb) rt+=(ra)*(rb)
29 #define MLSS(rt, ra, rb) rt-=(ra)*(rb)
30 
31 #define SUM8(op, sum, w, p) \
32 { \
33  op(sum, (w)[0 * 64], (p)[0 * 64]); \
34  op(sum, (w)[1 * 64], (p)[1 * 64]); \
35  op(sum, (w)[2 * 64], (p)[2 * 64]); \
36  op(sum, (w)[3 * 64], (p)[3 * 64]); \
37  op(sum, (w)[4 * 64], (p)[4 * 64]); \
38  op(sum, (w)[5 * 64], (p)[5 * 64]); \
39  op(sum, (w)[6 * 64], (p)[6 * 64]); \
40  op(sum, (w)[7 * 64], (p)[7 * 64]); \
41 }
42 
43 static void apply_window(const float *buf, const float *win1,
44  const float *win2, float *sum1, float *sum2, int len)
45 {
46  const vector float *win1a = (const vector float *) win1;
47  const vector float *win2a = (const vector float *) win2;
48  const vector float *bufa = (const vector float *) buf;
49  vector float *sum1a = (vector float *) sum1;
50  vector float *sum2a = (vector float *) sum2;
51  vector float av_uninit(v0), av_uninit(v4);
52  vector float v1, v2, v3;
53 
54  len = len >> 2;
55 
56 #define MULT(a, b) \
57  { \
58  v1 = vec_ld(a, win1a); \
59  v2 = vec_ld(b, win2a); \
60  v3 = vec_ld(a, bufa); \
61  v0 = vec_madd(v3, v1, v0); \
62  v4 = vec_madd(v2, v3, v4); \
63  }
64 
65  while (len--) {
66  v0 = vec_xor(v0, v0);
67  v4 = vec_xor(v4, v4);
68 
69  MULT( 0, 0);
70  MULT( 256, 64);
71  MULT( 512, 128);
72  MULT( 768, 192);
73  MULT(1024, 256);
74  MULT(1280, 320);
75  MULT(1536, 384);
76  MULT(1792, 448);
77 
78  vec_st(v0, 0, sum1a);
79  vec_st(v4, 0, sum2a);
80  sum1a++;
81  sum2a++;
82  win1a++;
83  win2a++;
84  bufa++;
85  }
86 }
87 
88 static void apply_window_mp3(float *in, float *win, int *unused, float *out,
89  int incr)
90 {
91  LOCAL_ALIGNED_16(float, suma, [17]);
92  LOCAL_ALIGNED_16(float, sumb, [17]);
93  LOCAL_ALIGNED_16(float, sumc, [17]);
94  LOCAL_ALIGNED_16(float, sumd, [17]);
95 
96  float sum;
97  int j;
98  float *out2 = out + 32 * incr;
99 
100  /* copy to avoid wrap */
101  memcpy(in + 512, in, 32 * sizeof(*in));
102 
103  apply_window(in + 16, win , win + 512, suma, sumc, 16);
104  apply_window(in + 32, win + 48, win + 640, sumb, sumd, 16);
105 
106  SUM8(MLSS, suma[0], win + 32, in + 48);
107 
108  sumc[ 0] = 0;
109  sumb[16] = 0;
110  sumd[16] = 0;
111 
112  out[0 ] = suma[ 0];
113  out += incr;
114  out2 -= incr;
115  for(j=1;j<16;j++) {
116  *out = suma[ j] - sumd[16-j];
117  *out2 = -sumb[16-j] - sumc[ j];
118  out += incr;
119  out2 -= incr;
120  }
121 
122  sum = 0;
123  SUM8(MLSS, sum, win + 16 + 32, in + 32);
124  *out = sum;
125 }
126 
128 {
130 }