git.sesse.net Git - ffmpeg/blob - libavcodec/sh4/idct_sh4.c

   1 /*
   2  * idct for sh4
   3  *
   4  * Copyright (c) 2001-2003 BERO <bero@geocities.co.jp>
   5  *
   6  * This file is part of FFmpeg.
   7  *
   8  * FFmpeg is free software; you can redistribute it and/or
   9  * modify it under the terms of the GNU Lesser General Public
  10  * License as published by the Free Software Foundation; either
  11  * version 2.1 of the License, or (at your option) any later version.
  12  *
  13  * FFmpeg is distributed in the hope that it will be useful,
  14  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  15  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  16  * Lesser General Public License for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public
  19  * License along with FFmpeg; if not, write to the Free Software
  20  * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
  21  */
  22
  23 #include "libavcodec/dsputil.h"
  24 #include "dsputil_sh4.h"
  25 #include "sh4.h"
  26
  27 #define c1      1.38703984532214752434  /* sqrt(2)*cos(1*pi/16) */
  28 #define c2      1.30656296487637657577  /* sqrt(2)*cos(2*pi/16) */
  29 #define c3      1.17587560241935884520  /* sqrt(2)*cos(3*pi/16) */
  30 #define c4      1.00000000000000000000  /* sqrt(2)*cos(4*pi/16) */
  31 #define c5      0.78569495838710234903  /* sqrt(2)*cos(5*pi/16) */
  32 #define c6      0.54119610014619712324  /* sqrt(2)*cos(6*pi/16) */
  33 #define c7      0.27589937928294311353  /* sqrt(2)*cos(7*pi/16) */
  34
  35 static const float even_table[] __attribute__ ((aligned(8))) = {
  36         c4, c4, c4, c4,
  37         c2, c6,-c6,-c2,
  38         c4,-c4,-c4, c4,
  39         c6,-c2, c2,-c6
  40 };
  41
  42 static const float odd_table[] __attribute__ ((aligned(8))) = {
  43         c1, c3, c5, c7,
  44         c3,-c7,-c1,-c5,
  45         c5,-c1, c7, c3,
  46         c7,-c5, c3,-c1
  47 };
  48
  49 #undef  c1
  50 #undef  c2
  51 #undef  c3
  52 #undef  c4
  53 #undef  c5
  54 #undef  c6
  55 #undef  c7
  56
  57 #define         load_matrix(table) \
  58     do { \
  59         const float *t = table; \
  60         __asm__ volatile( \
  61         "       fschg\n" \
  62         "       fmov   @%0+,xd0\n" \
  63         "       fmov   @%0+,xd2\n" \
  64         "       fmov   @%0+,xd4\n" \
  65         "       fmov   @%0+,xd6\n" \
  66         "       fmov   @%0+,xd8\n" \
  67         "       fmov   @%0+,xd10\n" \
  68         "       fmov   @%0+,xd12\n" \
  69         "       fmov   @%0+,xd14\n" \
  70         "       fschg\n" \
  71         : "+r"(t) \
  72         ); \
  73     } while (0)
  74
  75 #define         ftrv() \
  76                 __asm__ volatile("ftrv xmtrx,fv0" \
  77                 : "+f"(fr0),"+f"(fr1),"+f"(fr2),"+f"(fr3));
  78
  79 #define         DEFREG        \
  80         register float fr0 __asm__("fr0"); \
  81         register float fr1 __asm__("fr1"); \
  82         register float fr2 __asm__("fr2"); \
  83         register float fr3 __asm__("fr3")
  84
  85 #define         DESCALE(x,n)    (x)*(1.0f/(1<<(n)))
  86
  87 /* this code work worse on gcc cvs. 3.2.3 work fine */
  88
  89
  90 //optimized
  91
  92 void idct_sh4(DCTELEM *block)
  93 {
  94         DEFREG;
  95
  96         int i;
  97         float        tblock[8*8],*fblock;
  98         int ofs1,ofs2,ofs3;
  99         int fpscr;
 100
 101         fp_single_enter(fpscr);
 102
 103         /* row */
 104
 105         /* even part */
 106         load_matrix(even_table);
 107
 108         fblock = tblock+4;
 109         i = 8;
 110         do {
 111                 fr0 = block[0];
 112                 fr1 = block[2];
 113                 fr2 = block[4];
 114                 fr3 = block[6];
 115                 block+=8;
 116                 ftrv();
 117                 *--fblock = fr3;
 118                 *--fblock = fr2;
 119                 *--fblock = fr1;
 120                 *--fblock = fr0;
 121                 fblock+=8+4;
 122         } while(--i);
 123         block-=8*8;
 124         fblock-=8*8+4;
 125
 126         load_matrix(odd_table);
 127
 128         i = 8;
 129
 130         do {
 131                 float t0,t1,t2,t3;
 132                 fr0 = block[1];
 133                 fr1 = block[3];
 134                 fr2 = block[5];
 135                 fr3 = block[7];
 136                 block+=8;
 137                 ftrv();
 138                 t0 = *fblock++;
 139                 t1 = *fblock++;
 140                 t2 = *fblock++;
 141                 t3 = *fblock++;
 142                 fblock+=4;
 143                 *--fblock = t0 - fr0;
 144                 *--fblock = t1 - fr1;
 145                 *--fblock = t2 - fr2;
 146                 *--fblock = t3 - fr3;
 147                 *--fblock = t3 + fr3;
 148                 *--fblock = t2 + fr2;
 149                 *--fblock = t1 + fr1;
 150                 *--fblock = t0 + fr0;
 151                 fblock+=8;
 152         } while(--i);
 153         block-=8*8;
 154         fblock-=8*8;
 155
 156         /* col */
 157
 158         /* even part */
 159         load_matrix(even_table);
 160
 161         ofs1 = sizeof(float)*2*8;
 162         ofs2 = sizeof(float)*4*8;
 163         ofs3 = sizeof(float)*6*8;
 164
 165         i = 8;
 166
 167 #define        OA(fblock,ofs)   *(float*)((char*)fblock + ofs)
 168
 169         do {
 170                 fr0 = OA(fblock,   0);
 171                 fr1 = OA(fblock,ofs1);
 172                 fr2 = OA(fblock,ofs2);
 173                 fr3 = OA(fblock,ofs3);
 174                 ftrv();
 175                 OA(fblock,0   ) = fr0;
 176                 OA(fblock,ofs1) = fr1;
 177                 OA(fblock,ofs2) = fr2;
 178                 OA(fblock,ofs3) = fr3;
 179                 fblock++;
 180         } while(--i);
 181         fblock-=8;
 182
 183         load_matrix(odd_table);
 184
 185         i=8;
 186         do {
 187                 float t0,t1,t2,t3;
 188                 t0 = OA(fblock,   0); /* [8*0] */
 189                 t1 = OA(fblock,ofs1); /* [8*2] */
 190                 t2 = OA(fblock,ofs2); /* [8*4] */
 191                 t3 = OA(fblock,ofs3); /* [8*6] */
 192                 fblock+=8;
 193                 fr0 = OA(fblock,   0); /* [8*1] */
 194                 fr1 = OA(fblock,ofs1); /* [8*3] */
 195                 fr2 = OA(fblock,ofs2); /* [8*5] */
 196                 fr3 = OA(fblock,ofs3); /* [8*7] */
 197                 fblock+=-8+1;
 198                 ftrv();
 199                 block[8*0] = DESCALE(t0 + fr0,3);
 200                 block[8*7] = DESCALE(t0 - fr0,3);
 201                 block[8*1] = DESCALE(t1 + fr1,3);
 202                 block[8*6] = DESCALE(t1 - fr1,3);
 203                 block[8*2] = DESCALE(t2 + fr2,3);
 204                 block[8*5] = DESCALE(t2 - fr2,3);
 205                 block[8*3] = DESCALE(t3 + fr3,3);
 206                 block[8*4] = DESCALE(t3 - fr3,3);
 207                 block++;
 208         } while(--i);
 209
 210         fp_single_leave(fpscr);
 211 }