apps/codecs/lib/codeclib_misc.h

   1 /********************************************************************
   2  *                                                                  *
   3  * THIS FILE IS PART OF THE OggVorbis 'TREMOR' CODEC SOURCE CODE.   *
   4  *                                                                  *
   5  * USE, DISTRIBUTION AND REPRODUCTION OF THIS LIBRARY SOURCE IS     *
   6  * GOVERNED BY A BSD-STYLE SOURCE LICENSE INCLUDED WITH THIS SOURCE *
   7  * IN 'COPYING'. PLEASE READ THESE TERMS BEFORE DISTRIBUTING.       *
   8  *                                                                  *
   9  * THE OggVorbis 'TREMOR' SOURCE CODE IS (C) COPYRIGHT 1994-2002    *
  10  * BY THE Xiph.Org FOUNDATION http://www.xiph.org/                  *
  11  *                                                                  *
  12  ********************************************************************
  13
  14  function: miscellaneous math and prototypes
  15
  16  ********************************************************************/
  17
  18 //#include "config-tremor.h"
  19
  20 #ifndef _V_RANDOM_H_
  21 #define _V_RANDOM_H_
  22 //#include "ivorbiscodec.h"
  23 //#include "os_types.h"
  24
  25 //#include "asm_arm.h"
  26 //#include "asm_mcf5249.h"
  27
  28
  29 /* Some prototypes that were not defined elsewhere */
  30 //void *_vorbis_block_alloc(vorbis_block *vb,long bytes);
  31 //void _vorbis_block_ripcord(vorbis_block *vb);
  32 //extern int _ilog(unsigned int v);
  33
  34 #ifndef _V_WIDE_MATH
  35 #define _V_WIDE_MATH
  36
  37 #ifndef ROCKBOX
  38 #include <inttypes.h>
  39 #endif /* ROCKBOX */
  40
  41 #ifndef  _LOW_ACCURACY_
  42 /* 64 bit multiply */
  43 /* #include <sys/types.h> */
  44
  45 #if ROCKBOX_LITTLE_ENDIAN == 1
  46 union magic {
  47   struct {
  48     int32_t lo;
  49     int32_t hi;
  50   } halves;
  51   int64_t whole;
  52 };
  53 #elif ROCKBOX_BIG_ENDIAN == 1
  54 union magic {
  55   struct {
  56     int32_t hi;
  57     int32_t lo;
  58   } halves;
  59   int64_t whole;
  60 };
  61 #endif
  62
  63 static inline int32_t MULT32(int32_t x, int32_t y) {
  64   union magic magic;
  65   magic.whole = (int64_t)x * y;
  66   return magic.halves.hi;
  67 }
  68 static inline int32_t MULT31(int32_t x, int32_t y) {
  69   return MULT32(x,y)<<1;
  70 }
  71
  72 static inline int32_t MULT31_SHIFT15(int32_t x, int32_t y) {
  73   union magic magic;
  74   magic.whole  = (int64_t)x * y;
  75   return ((uint32_t)(magic.halves.lo)>>15) | ((magic.halves.hi)<<17);
  76 }
  77
  78 #else
  79 /* 32 bit multiply, more portable but less accurate */
  80
  81 /*
  82  * Note: Precision is biased towards the first argument therefore ordering
  83  * is important.  Shift values were chosen for the best sound quality after
  84  * many listening tests.
  85  */
  86
  87 /*
  88  * For MULT32 and MULT31: The second argument is always a lookup table
  89  * value already preshifted from 31 to 8 bits.  We therefore take the
  90  * opportunity to save on text space and use unsigned char for those
  91  * tables in this case.
  92  */
  93
  94 static inline int32_t MULT32(int32_t x, int32_t y) {
  95   return (x >> 9) * y;  /* y preshifted >>23 */
  96 }
  97
  98 static inline int32_t MULT31(int32_t x, int32_t y) {
  99   return (x >> 8) * y;  /* y preshifted >>23 */
 100 }
 101
 102 static inline int32_t MULT31_SHIFT15(int32_t x, int32_t y) {
 103   return (x >> 6) * y;  /* y preshifted >>9 */
 104 }
 105 #endif
 106
 107 /*
 108  * The XPROD functions are meant to optimize the cross products found all
 109  * over the place in mdct.c by forcing memory operation ordering to avoid
 110  * unnecessary register reloads as soon as memory is being written to.
 111  * However this is only beneficial on CPUs with a sane number of general
 112  * purpose registers which exclude the Intel x86.  On Intel, better let the
 113  * compiler actually reload registers directly from original memory by using
 114  * macros.
 115  */
 116
 117 /* replaced XPROD32 with a macro to avoid memory reference
 118    _x, _y are the results (must be l-values) */
 119 #define XPROD32(_a, _b, _t, _v, _x, _y)         \
 120   { (_x)=MULT32(_a,_t)+MULT32(_b,_v);           \
 121     (_y)=MULT32(_b,_t)-MULT32(_a,_v); }
 122
 123
 124 #ifdef __i386__
 125
 126 #define XPROD31(_a, _b, _t, _v, _x, _y)         \
 127   { *(_x)=MULT31(_a,_t)+MULT31(_b,_v);          \
 128     *(_y)=MULT31(_b,_t)-MULT31(_a,_v); }
 129 #define XNPROD31(_a, _b, _t, _v, _x, _y)        \
 130   { *(_x)=MULT31(_a,_t)-MULT31(_b,_v);          \
 131     *(_y)=MULT31(_b,_t)+MULT31(_a,_v); }
 132
 133 #else
 134
 135 static inline void XPROD31(int32_t  a, int32_t  b,
 136                            int32_t  t, int32_t  v,
 137                            int32_t *x, int32_t *y)
 138 {
 139   *x = MULT31(a, t) + MULT31(b, v);
 140   *y = MULT31(b, t) - MULT31(a, v);
 141 }
 142
 143 static inline void XNPROD31(int32_t  a, int32_t  b,
 144                             int32_t  t, int32_t  v,
 145                             int32_t *x, int32_t *y)
 146 {
 147   *x = MULT31(a, t) - MULT31(b, v);
 148   *y = MULT31(b, t) + MULT31(a, v);
 149 }
 150 #endif
 151
 152 #ifndef _V_VECT_OPS
 153 #define _V_VECT_OPS
 154
 155 static inline
 156 void vect_add(int32_t *x, int32_t *y, int n)
 157 {
 158   while (n>0) {
 159     *x++ += *y++;
 160     n--;
 161   }
 162 }
 163
 164 static inline
 165 void vect_copy(int32_t *x, int32_t *y, int n)
 166 {
 167   while (n>0) {
 168     *x++ = *y++;
 169     n--;
 170   }
 171 }
 172
 173 static inline
 174 void vect_mult_fw(int32_t *data, int32_t *window, int n)
 175 {
 176   while(n>0) {
 177     *data = MULT31(*data, *window);
 178     data++;
 179     window++;
 180     n--;
 181   }
 182 }
 183
 184 static inline
 185 void vect_mult_bw(int32_t *data, int32_t *window, int n)
 186 {
 187   while(n>0) {
 188     *data = MULT31(*data, *window);
 189     data++;
 190     window--;
 191     n--;
 192   }
 193 }
 194 #endif
 195
 196 #endif
 197
 198 #ifndef _V_CLIP_MATH
 199 #define _V_CLIP_MATH
 200
 201 static inline int32_t CLIP_TO_15(int32_t x) {
 202   int ret=x;
 203   ret-= ((x<=32767)-1)&(x-32767);
 204   ret-= ((x>=-32768)-1)&(x+32768);
 205   return(ret);
 206 }
 207
 208 #endif
 209
 210 static inline int32_t VFLOAT_MULT(int32_t a,int32_t ap,
 211                                       int32_t b,int32_t bp,
 212                                       int32_t *p){
 213   if(a && b){
 214 #ifndef _LOW_ACCURACY_
 215     *p=ap+bp+32;
 216     return MULT32(a,b);
 217 #else
 218     *p=ap+bp+31;
 219     return (a>>15)*(b>>16);
 220 #endif
 221   }else
 222     return 0;
 223 }
 224
 225 /*static inline int32_t VFLOAT_MULTI(int32_t a,int32_t ap,
 226                                       int32_t i,
 227                                       int32_t *p){
 228
 229   int ip=_ilog(abs(i))-31;
 230   return VFLOAT_MULT(a,ap,i<<-ip,ip,p);
 231 }
 232 */
 233 static inline int32_t VFLOAT_ADD(int32_t a,int32_t ap,
 234                                       int32_t b,int32_t bp,
 235                                       int32_t *p){
 236
 237   if(!a){
 238     *p=bp;
 239     return b;
 240   }else if(!b){
 241     *p=ap;
 242     return a;
 243   }
 244
 245   /* yes, this can leak a bit. */
 246   if(ap>bp){
 247     int shift=ap-bp+1;
 248     *p=ap+1;
 249     a>>=1;
 250     if(shift<32){
 251       b=(b+(1<<(shift-1)))>>shift;
 252     }else{
 253       b=0;
 254     }
 255   }else{
 256     int shift=bp-ap+1;
 257     *p=bp+1;
 258     b>>=1;
 259     if(shift<32){
 260       a=(a+(1<<(shift-1)))>>shift;
 261     }else{
 262       a=0;
 263     }
 264   }
 265
 266   a+=b;
 267   if((a&0xc0000000)==0xc0000000 ||
 268      (a&0xc0000000)==0){
 269     a<<=1;
 270     (*p)--;
 271   }
 272   return(a);
 273 }
 274
 275 #endif
 276