crypto/external/bsd/heimdal/dist/lib/hcrypto/libtommath/etc/tune.c

   1 /*      $NetBSD: tune.c,v 1.1.1.2 2014/04/24 12:45:39 pettai Exp $      */
   2
   3 /* Tune the Karatsuba parameters
   4  *
   5  * Tom St Denis, tomstdenis@gmail.com
   6  */
   7 #include <tommath.h>
   8 #include <time.h>
   9
  10 /* how many times todo each size mult.  Depends on your computer.  For slow computers
  11  * this can be low like 5 or 10.  For fast [re: Athlon] should be 25 - 50 or so
  12  */
  13 #define TIMES (1UL<<14UL)
  14
  15 /* RDTSC from Scott Duplichan */
  16 static ulong64 TIMFUNC (void)
  17    {
  18    #if defined __GNUC__
  19       #if defined(__i386__) || defined(__x86_64__)
  20          unsigned long long a;
  21          __asm__ __volatile__ ("rdtsc\nmovl %%eax,%0\nmovl %%edx,4+%0\n"::"m"(a):"%eax","%edx");
  22          return a;
  23       #else /* gcc-IA64 version */
  24          unsigned long result;
  25          __asm__ __volatile__("mov %0=ar.itc" : "=r"(result) :: "memory");
  26          while (__builtin_expect ((int) result == -1, 0))
  27          __asm__ __volatile__("mov %0=ar.itc" : "=r"(result) :: "memory");
  28          return result;
  29       #endif
  30
  31    // Microsoft and Intel Windows compilers
  32    #elif defined _M_IX86
  33      __asm rdtsc
  34    #elif defined _M_AMD64
  35      return __rdtsc ();
  36    #elif defined _M_IA64
  37      #if defined __INTEL_COMPILER
  38        #include <ia64intrin.h>
  39      #endif
  40       return __getReg (3116);
  41    #else
  42      #error need rdtsc function for this build
  43    #endif
  44    }
  45
  46
  47 #ifndef X86_TIMER
  48
  49 /* generic ISO C timer */
  50 ulong64 LBL_T;
  51 void t_start(void) { LBL_T = TIMFUNC(); }
  52 ulong64 t_read(void) { return TIMFUNC() - LBL_T; }
  53
  54 #else
  55 extern void t_start(void);
  56 extern ulong64 t_read(void);
  57 #endif
  58
  59 ulong64 time_mult(int size, int s)
  60 {
  61   unsigned long     x;
  62   mp_int  a, b, c;
  63   ulong64 t1;
  64
  65   mp_init (&a);
  66   mp_init (&b);
  67   mp_init (&c);
  68
  69   mp_rand (&a, size);
  70   mp_rand (&b, size);
  71
  72   if (s == 1) {
  73       KARATSUBA_MUL_CUTOFF = size;
  74   } else {
  75       KARATSUBA_MUL_CUTOFF = 100000;
  76   }
  77
  78   t_start();
  79   for (x = 0; x < TIMES; x++) {
  80       mp_mul(&a,&b,&c);
  81   }
  82   t1 = t_read();
  83   mp_clear (&a);
  84   mp_clear (&b);
  85   mp_clear (&c);
  86   return t1;
  87 }
  88
  89 ulong64 time_sqr(int size, int s)
  90 {
  91   unsigned long     x;
  92   mp_int  a, b;
  93   ulong64 t1;
  94
  95   mp_init (&a);
  96   mp_init (&b);
  97
  98   mp_rand (&a, size);
  99
 100   if (s == 1) {
 101       KARATSUBA_SQR_CUTOFF = size;
 102   } else {
 103       KARATSUBA_SQR_CUTOFF = 100000;
 104   }
 105
 106   t_start();
 107   for (x = 0; x < TIMES; x++) {
 108       mp_sqr(&a,&b);
 109   }
 110   t1 = t_read();
 111   mp_clear (&a);
 112   mp_clear (&b);
 113   return t1;
 114 }
 115
 116 int
 117 main (void)
 118 {
 119   ulong64 t1, t2;
 120   int x, y;
 121
 122   for (x = 8; ; x += 2) {
 123      t1 = time_mult(x, 0);
 124      t2 = time_mult(x, 1);
 125      printf("%d: %9llu %9llu, %9llu\n", x, t1, t2, t2 - t1);
 126      if (t2 < t1) break;
 127   }
 128   y = x;
 129
 130   for (x = 8; ; x += 2) {
 131      t1 = time_sqr(x, 0);
 132      t2 = time_sqr(x, 1);
 133      printf("%d: %9llu %9llu, %9llu\n", x, t1, t2, t2 - t1);
 134      if (t2 < t1) break;
 135   }
 136   printf("KARATSUBA_MUL_CUTOFF = %d\n", y);
 137   printf("KARATSUBA_SQR_CUTOFF = %d\n", x);
 138
 139   return 0;
 140 }
 141
 142 /* Source: /cvs/libtom/libtommath/etc/tune.c,v  */
 143 /* Revision: 1.3  */
 144 /* Date: 2006/03/31 14:18:47  */