libavcodec/mathops.h

   1 /*
   2  * simple math operations
   3  * Copyright (c) 2001, 2002 Fabrice Bellard
   4  * Copyright (c) 2006 Michael Niedermayer <michaelni@gmx.at> et al
   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 #ifndef AVCODEC_MATHOPS_H
  23 #define AVCODEC_MATHOPS_H
  24
  25 #include "libavutil/common.h"
  26
  27 #if   ARCH_ARM
  28 #   include "arm/mathops.h"
  29 #elif ARCH_BFIN
  30 #   include "bfin/mathops.h"
  31 #elif ARCH_MIPS
  32 #   include "mips/mathops.h"
  33 #elif ARCH_PPC
  34 #   include "ppc/mathops.h"
  35 #elif ARCH_X86
  36 #   include "x86/mathops.h"
  37 #endif
  38
  39 /* generic implementation */
  40
  41 #ifndef MULL
  42 #   define MULL(a,b,s) (((int64_t)(a) * (int64_t)(b)) >> (s))
  43 #endif
  44
  45 #ifndef MULH
  46 //gcc 3.4 creates an incredibly bloated mess out of this
  47 //#    define MULH(a,b) (((int64_t)(a) * (int64_t)(b))>>32)
  48
  49 static av_always_inline int MULH(int a, int b){
  50     return ((int64_t)(a) * (int64_t)(b))>>32;
  51 }
  52 #endif
  53
  54 #ifndef MUL64
  55 #   define MUL64(a,b) ((int64_t)(a) * (int64_t)(b))
  56 #endif
  57
  58 #ifndef MAC64
  59 #   define MAC64(d, a, b) ((d) += MUL64(a, b))
  60 #endif
  61
  62 #ifndef MLS64
  63 #   define MLS64(d, a, b) ((d) -= MUL64(a, b))
  64 #endif
  65
  66 /* signed 16x16 -> 32 multiply add accumulate */
  67 #ifndef MAC16
  68 #   define MAC16(rt, ra, rb) rt += (ra) * (rb)
  69 #endif
  70
  71 /* signed 16x16 -> 32 multiply */
  72 #ifndef MUL16
  73 #   define MUL16(ra, rb) ((ra) * (rb))
  74 #endif
  75
  76 #ifndef MLS16
  77 #   define MLS16(rt, ra, rb) ((rt) -= (ra) * (rb))
  78 #endif
  79
  80 /* median of 3 */
  81 #ifndef mid_pred
  82 #define mid_pred mid_pred
  83 static inline av_const int mid_pred(int a, int b, int c)
  84 {
  85 #if 0
  86     int t= (a-b)&((a-b)>>31);
  87     a-=t;
  88     b+=t;
  89     b-= (b-c)&((b-c)>>31);
  90     b+= (a-b)&((a-b)>>31);
  91
  92     return b;
  93 #else
  94     if(a>b){
  95         if(c>b){
  96             if(c>a) b=a;
  97             else    b=c;
  98         }
  99     }else{
 100         if(b>c){
 101             if(c>a) b=c;
 102             else    b=a;
 103         }
 104     }
 105     return b;
 106 #endif
 107 }
 108 #endif
 109
 110 #ifndef sign_extend
 111 static inline av_const int sign_extend(int val, unsigned bits)
 112 {
 113     return (val << (INT_BIT - bits)) >> (INT_BIT - bits);
 114 }
 115 #endif
 116
 117 #endif /* AVCODEC_MATHOPS_H */
 118