summaryrefslogtreecommitdiffstats
path: root/libavcodec/ppc/gmc_altivec.c
blob: 0c82c397186a137a0baf99834d15be7ed8a7a8ba (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
/*
 * GMC (Global Motion Compensation)
 * AltiVec-enabled
 * Copyright (c) 2003 Romain Dolbeau <romain@dolbeau.org>
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
 */

#include "../dsputil.h"

#include "gcc_fixes.h"

#include "dsputil_altivec.h"

/*
  altivec-enhanced gmc1. ATM this code assume stride is a multiple of 8,
  to preserve proper dst alignement.
*/
#define GMC1_PERF_COND (h==8)
void gmc1_altivec(uint8_t *dst /* align 8 */, uint8_t *src /* align1 */, int stride, int h, int x16, int y16, int rounder)
{
POWERPC_PERF_DECLARE(altivec_gmc1_num, GMC1_PERF_COND);
#ifdef ALTIVEC_USE_REFERENCE_C_CODE
    const int A=(16-x16)*(16-y16);
    const int B=(   x16)*(16-y16);
    const int C=(16-x16)*(   y16);
    const int D=(   x16)*(   y16);
    int i;

POWERPC_PERF_START_COUNT(altivec_gmc1_num, GMC1_PERF_COND);

    for(i=0; i<h; i++)
    {
        dst[0]= (A*src[0] + B*src[1] + C*src[stride+0] + D*src[stride+1] + rounder)>>8;
        dst[1]= (A*src[1] + B*src[2] + C*src[stride+1] + D*src[stride+2] + rounder)>>8;
        dst[2]= (A*src[2] + B*src[3] + C*src[stride+2] + D*src[stride+3] + rounder)>>8;
        dst[3]= (A*src[3] + B*src[4] + C*src[stride+3] + D*src[stride+4] + rounder)>>8;
        dst[4]= (A*src[4] + B*src[5] + C*src[stride+4] + D*src[stride+5] + rounder)>>8;
        dst[5]= (A*src[5] + B*src[6] + C*src[stride+5] + D*src[stride+6] + rounder)>>8;
        dst[6]= (A*src[6] + B*src[7] + C*src[stride+6] + D*src[stride+7] + rounder)>>8;
        dst[7]= (A*src[7] + B*src[8] + C*src[stride+7] + D*src[stride+8] + rounder)>>8;
        dst+= stride;
        src+= stride;
    }

POWERPC_PERF_STOP_COUNT(altivec_gmc1_num, GMC1_PERF_COND);

#else /* ALTIVEC_USE_REFERENCE_C_CODE */
    const unsigned short __attribute__ ((aligned(16))) rounder_a[8] =
      {rounder, rounder, rounder, rounder,
       rounder, rounder, rounder, rounder};
    const unsigned short __attribute__ ((aligned(16))) ABCD[8] =
      {
        (16-x16)*(16-y16), /* A */
        (   x16)*(16-y16), /* B */
        (16-x16)*(   y16), /* C */
        (   x16)*(   y16), /* D */
        0, 0, 0, 0         /* padding */
      };
    register const_vector unsigned char vczero = (const_vector unsigned char)vec_splat_u8(0);
    register const_vector unsigned short vcsr8 = (const_vector unsigned short)vec_splat_u16(8);
    register vector unsigned char dstv, dstv2, src_0, src_1, srcvA, srcvB, srcvC, srcvD;
    register vector unsigned short Av, Bv, Cv, Dv, rounderV, tempA, tempB, tempC, tempD;
    int i;
    unsigned long dst_odd = (unsigned long)dst & 0x0000000F;
    unsigned long src_really_odd = (unsigned long)src & 0x0000000F;


POWERPC_PERF_START_COUNT(altivec_gmc1_num, GMC1_PERF_COND);

    tempA = vec_ld(0, (unsigned short*)ABCD);
    Av = vec_splat(tempA, 0);
    Bv = vec_splat(tempA, 1);
    Cv = vec_splat(tempA, 2);
    Dv = vec_splat(tempA, 3);

    rounderV = vec_ld(0, (unsigned short*)rounder_a);

    // we'll be able to pick-up our 9 char elements
    // at src from those 32 bytes
    // we load the first batch here, as inside the loop
    // we can re-use 'src+stride' from one iteration
    // as the 'src' of the next.
    src_0 = vec_ld(0, src);
    src_1 = vec_ld(16, src);
    srcvA = vec_perm(src_0, src_1, vec_lvsl(0, src));

    if (src_really_odd != 0x0000000F)
    { // if src & 0xF == 0xF, then (src+1) is properly aligned on the second vector.
      srcvB = vec_perm(src_0, src_1, vec_lvsl(1, src));
    }
    else
    {
      srcvB = src_1;
    }
    srcvA = vec_mergeh(vczero, srcvA);
    srcvB = vec_mergeh(vczero, srcvB);

    for(i=0; i<h; i++)
    {
      dst_odd = (unsigned long)dst & 0x0000000F;
      src_really_odd = (((unsigned long)src) + stride) & 0x0000000F;

      dstv = vec_ld(0, dst);

      // we we'll be able to pick-up our 9 char elements
      // at src + stride from those 32 bytes
      // then reuse the resulting 2 vectors srvcC and srcvD
      // as the next srcvA and srcvB
      src_0 = vec_ld(stride + 0, src);
      src_1 = vec_ld(stride + 16, src);
      srcvC = vec_perm(src_0, src_1, vec_lvsl(stride + 0, src));

      if (src_really_odd != 0x0000000F)
      { // if src & 0xF == 0xF, then (src+1) is properly aligned on the second vector.
        srcvD = vec_perm(src_0, src_1, vec_lvsl(stride + 1, src));
      }
      else
      {
        srcvD = src_1;
      }

      srcvC = vec_mergeh(vczero, srcvC);
      srcvD = vec_mergeh(vczero, srcvD);


      // OK, now we (finally) do the math :-)
      // those four instructions replaces 32 int muls & 32 int adds.
      // isn't AltiVec nice ?
      tempA = vec_mladd((vector unsigned short)srcvA, Av, rounderV);
      tempB = vec_mladd((vector unsigned short)srcvB, Bv, tempA);
      tempC = vec_mladd((vector unsigned short)srcvC, Cv, tempB);
      tempD = vec_mladd((vector unsigned short)srcvD, Dv, tempC);

      srcvA = srcvC;
      srcvB = srcvD;

      tempD = vec_sr(tempD, vcsr8);

      dstv2 = vec_pack(tempD, (vector unsigned short)vczero);

      if (dst_odd)
      {
        dstv2 = vec_perm(dstv, dstv2, vcprm(0,1,s0,s1));
      }
      else
      {
        dstv2 = vec_perm(dstv, dstv2, vcprm(s0,s1,2,3));
      }

      vec_st(dstv2, 0, dst);

      dst += stride;
      src += stride;
    }

POWERPC_PERF_STOP_COUNT(altivec_gmc1_num, GMC1_PERF_COND);

#endif /* ALTIVEC_USE_REFERENCE_C_CODE */
}
OpenPOWER on IntegriCloud