libmpcodecs/cmmx.h

   1 /*
   2  * x86 MMX and MMX2 packed byte operations in portable C.
   3  * Extra instructions: pdiffub, pcmpzb, psumbw, pcmpgtub
   4  * Author: Zoltan Hidvegi
   5  */
   6
   7 #ifndef MPLAYER_CMMX_H
   8 #define MPLAYER_CMMX_H
   9
  10 typedef unsigned long cmmx_t;
  11
  12 #define ONE_BYTES (~(cmmx_t)0 / 255)
  13 #define SIGN_BITS (ONE_BYTES << 7)
  14 #define LOWBW_MASK (~(cmmx_t)0 / 257)
  15
  16 static inline cmmx_t
  17 paddb(cmmx_t a, cmmx_t b)
  18 {
  19     return ((a & ~SIGN_BITS) + (b & ~SIGN_BITS)) ^ ((a^b) & SIGN_BITS);
  20 }
  21
  22 static inline cmmx_t
  23 psubb(cmmx_t a, cmmx_t b)
  24 {
  25     return ((a | SIGN_BITS) - (b & ~SIGN_BITS)) ^ (~(a^b) & SIGN_BITS);
  26 }
  27
  28 static inline cmmx_t
  29 paddusb(cmmx_t a, cmmx_t b)
  30 {
  31     cmmx_t s = (a & ~SIGN_BITS) + (b & ~SIGN_BITS);
  32     cmmx_t abs = (a | b) & SIGN_BITS;
  33     cmmx_t c = abs & (s | (a & b));
  34     return s | abs | (abs - (c >> 7));
  35 }
  36
  37 static inline cmmx_t
  38 paddusb_s(cmmx_t a, cmmx_t b)
  39 {
  40     cmmx_t sum = a+b;
  41     cmmx_t ov = sum & SIGN_BITS;
  42     return sum + (sum ^ (ov - (ov>>7)));
  43 }
  44
  45 static inline cmmx_t
  46 psubusb(cmmx_t a, cmmx_t b)
  47 {
  48     cmmx_t s = (a | SIGN_BITS) - (b & ~SIGN_BITS);
  49     cmmx_t anb = a & ~b;
  50     cmmx_t c = (anb | (s & ~(a^b))) & SIGN_BITS;
  51     return s & ((c & anb) | (c - (c >> 7)));
  52 }
  53
  54 static inline cmmx_t
  55 psubusb_s(cmmx_t a, cmmx_t b)
  56 {
  57     cmmx_t d = (a|SIGN_BITS) - b;
  58     cmmx_t m = d & SIGN_BITS;
  59     return d & (m - (m>>7));
  60 }
  61
  62 static inline cmmx_t
  63 pcmpgtub(cmmx_t b, cmmx_t a)
  64 {
  65     cmmx_t s = (a | SIGN_BITS) - (b & ~SIGN_BITS);
  66     cmmx_t ret = ((~a & b) | (~s & ~(a ^ b))) & SIGN_BITS;
  67     return ret | (ret - (ret >> 7));
  68 }
  69
  70 static inline cmmx_t
  71 pdiffub(cmmx_t a, cmmx_t b)
  72 {
  73     cmmx_t xs = (~a ^ b) & SIGN_BITS;
  74     cmmx_t s = ((a | SIGN_BITS) - (b & ~SIGN_BITS)) ^ xs;
  75     cmmx_t gt = ((~a & b) | (s & xs)) & SIGN_BITS;
  76     cmmx_t gt7 = gt >> 7;
  77     return (s ^ gt ^ (gt - gt7)) + gt7;
  78 }
  79
  80 static inline cmmx_t
  81 pdiffub_s(cmmx_t a, cmmx_t b)
  82 {
  83     cmmx_t d = (a|SIGN_BITS) - b;
  84     cmmx_t g = (~d & SIGN_BITS) >> 7;
  85     return (d ^ (SIGN_BITS-g)) + g;
  86 }
  87
  88 static inline cmmx_t
  89 pmaxub(cmmx_t a, cmmx_t b)
  90 {
  91     return psubusb(a,b) + b;
  92 }
  93
  94 static inline cmmx_t
  95 pminub(cmmx_t a, cmmx_t b)
  96 {
  97     return paddusb(a,~b) - ~b;
  98 }
  99
 100 static inline cmmx_t
 101 pminub_s(cmmx_t a, cmmx_t b)
 102 {
 103     cmmx_t d = (a|SIGN_BITS) - b;
 104     cmmx_t m = ~SIGN_BITS + ((d&SIGN_BITS)>>7);
 105     return ((d&m) + b) & ~SIGN_BITS;
 106 }
 107
 108 static inline cmmx_t
 109 pavgb(cmmx_t a, cmmx_t b)
 110 {
 111     cmmx_t ao = a & ONE_BYTES;
 112     cmmx_t bo = b & ONE_BYTES;
 113     return ((a^ao)>>1) + ((b^bo)>>1) + (ao|bo);
 114 }
 115
 116 static inline cmmx_t
 117 pavgb_s(cmmx_t a, cmmx_t b)
 118 {
 119     return ((a+b+ONE_BYTES)>>1) & ~SIGN_BITS;
 120 }
 121
 122 static inline cmmx_t
 123 p31avgb(cmmx_t a, cmmx_t b)
 124 {
 125     cmmx_t ao = a & (3*ONE_BYTES);
 126     cmmx_t bo = b & (3*ONE_BYTES);
 127     return 3*((a^ao)>>2) + ((b^bo)>>2) +
 128         (((3*ao+bo+2*ONE_BYTES)>>2) & (3*ONE_BYTES));
 129 }
 130
 131 static inline cmmx_t
 132 p31avgb_s(cmmx_t a, cmmx_t b)
 133 {
 134     cmmx_t avg = ((a+b)>>1) & ~SIGN_BITS;
 135     return pavgb_s(avg, a);
 136 }
 137
 138 static inline unsigned long
 139 psumbw(cmmx_t a)
 140 {
 141     cmmx_t t = (a & LOWBW_MASK) + ((a>>8) & LOWBW_MASK);
 142     unsigned long ret =
 143         (unsigned long)t + (unsigned long)(t >> (4*sizeof(cmmx_t)));
 144     if (sizeof(cmmx_t) > 4)
 145         ret += ret >> 16;
 146     return ret & 0xffff;
 147 }
 148
 149 static inline unsigned long
 150 psumbw_s(cmmx_t a)
 151 {
 152     unsigned long ret =
 153         (unsigned long)a + (unsigned long)(a >> (4*sizeof(cmmx_t)));
 154     if (sizeof(cmmx_t) <= 4)
 155         return (ret & 0xff) + ((ret>>8) & 0xff);
 156     ret = (ret & 0xff00ff) + ((ret>>8) & 0xff00ff);
 157     ret += ret >> 16;
 158     return ret & 0xffff;
 159 }
 160
 161 static inline unsigned long
 162 psadbw(cmmx_t a, cmmx_t b)
 163 {
 164     return psumbw(pdiffub(a,b));
 165 }
 166
 167 static inline unsigned long
 168 psadbw_s(cmmx_t a, cmmx_t b)
 169 {
 170     return psumbw_s(pdiffub_s(a,b));
 171 }
 172
 173 static inline cmmx_t
 174 pcmpzb(cmmx_t a)
 175 {
 176     cmmx_t ret = (((a | SIGN_BITS) - ONE_BYTES) | a) & SIGN_BITS;
 177     return ~(ret | (ret - (ret >> 7)));
 178 }
 179
 180 static inline cmmx_t
 181 pcmpeqb(cmmx_t a, cmmx_t b)
 182 {
 183     return pcmpzb(a ^ b);
 184 }
 185
 186 #endif /* MPLAYER_CMMX_H */