lib/zlib/contrib/masmx86/gvmat32c.c

   1 /* gvmat32.c -- C portion of the optimized longest_match for 32 bits x86
   2  * Copyright (C) 1995-1996 Jean-loup Gailly and Gilles Vollant.
   3  * File written by Gilles Vollant, by modifiying the longest_match
   4  *  from Jean-loup Gailly in deflate.c
   5  *  it prepare all parameters and call the assembly longest_match_gvasm
   6  *  longest_match execute standard C code is wmask != 0x7fff
   7  *     (assembly code is faster with a fixed wmask)
   8  *
   9  * Read comment at beginning of gvmat32.asm for more information
  10  */
  11
  12 #if defined(ASMV) && (!defined(NOOLDPENTIUMCODE))
  13 #include "deflate.h"
  14
  15 /* if your C compiler don't add underline before function name,
  16         define ADD_UNDERLINE_ASMFUNC */
  17 #ifdef ADD_UNDERLINE_ASMFUNC
  18 #define longest_match_7fff _longest_match_7fff
  19 #define longest_match_686  _longest_match_686
  20 #define cpudetect32        _cpudetect32
  21 #endif
  22
  23
  24 unsigned long cpudetect32();
  25
  26 uInt longest_match_c(
  27     deflate_state *s,
  28     IPos cur_match);                             /* current match */
  29
  30
  31 uInt longest_match_7fff(
  32     deflate_state *s,
  33     IPos cur_match);                             /* current match */
  34
  35 uInt longest_match_686(
  36     deflate_state *s,
  37     IPos cur_match);                             /* current match */
  38
  39
  40 static uInt iIsPPro=2;
  41
  42 void match_init ()
  43 {
  44     iIsPPro = (((cpudetect32()/0x100)&0xf)>=6) ? 1 : 0;
  45 }
  46
  47 uInt longest_match(
  48     deflate_state *s,
  49     IPos cur_match)                             /* current match */
  50 {
  51     if (iIsPPro!=0)
  52         return longest_match_686(s,cur_match);
  53
  54     if (s->w_mask != 0x7fff)
  55         return longest_match_686(s,cur_match);
  56
  57     /* now ((s->w_mask == 0x7fff) && (iIsPPro==0)) */
  58         return longest_match_7fff(s,cur_match);
  59 }
  60
  61
  62 #endif /* defined(ASMV) && (!defined(NOOLDPENTIUMCODE)) */