1 files changed, 107 insertions, 0 deletions
diff --git a/libtommath/etc/tune.c b/libtommath/etc/tune.c
new file mode 100644
index 0000000..14aace2
--- /dev/null
+++ b/libtommath/etc/tune.c
@@ -0,0 +1,107 @@
+/* Tune the Karatsuba parameters
+ *
+ * Tom St Denis, tomstdenis@iahu.ca
+ */
+#include <tommath.h>
+#include <time.h>
+
+/* how many times todo each size mult.  Depends on your computer.  For slow computers
+ * this can be low like 5 or 10.  For fast [re: Athlon] should be 25 - 50 or so 
+ */
+#define TIMES (1UL<<14UL)
+
+
+#ifndef X86_TIMER
+
+/* generic ISO C timer */
+ulong64 LBL_T;
+void t_start(void) { LBL_T = clock(); }
+ulong64 t_read(void) { return clock() - LBL_T; }
+
+#else
+extern void t_start(void);
+extern ulong64 t_read(void);
+#endif
+
+ulong64 time_mult(int size, int s)
+{
+  unsigned long     x;
+  mp_int  a, b, c;
+  ulong64 t1;
+
+  mp_init (&a);
+  mp_init (&b);
+  mp_init (&c);
+
+  mp_rand (&a, size);
+  mp_rand (&b, size);
+
+  if (s == 1) { 
+      KARATSUBA_MUL_CUTOFF = size;
+  } else {
+      KARATSUBA_MUL_CUTOFF = 100000;
+  }
+
+  t_start();
+  for (x = 0; x < TIMES; x++) {
+      mp_mul(&a,&b,&c);
+  }
+  t1 = t_read();
+  mp_clear (&a);
+  mp_clear (&b);
+  mp_clear (&c);
+  return t1;
+}
+
+ulong64 time_sqr(int size, int s)
+{
+  unsigned long     x;
+  mp_int  a, b;
+  ulong64 t1;
+
+  mp_init (&a);
+  mp_init (&b);
+
+  mp_rand (&a, size);
+
+  if (s == 1) { 
+      KARATSUBA_SQR_CUTOFF = size;
+  } else {
+      KARATSUBA_SQR_CUTOFF = 100000;
+  }
+
+  t_start();
+  for (x = 0; x < TIMES; x++) {
+      mp_sqr(&a,&b);
+  }
+  t1 = t_read();
+  mp_clear (&a);
+  mp_clear (&b);
+  return t1;
+}
+
+int
+main (void)
+{
+  ulong64 t1, t2;
+  int x, y;
+
+  for (x = 8; ; x += 2) { 
+     t1 = time_mult(x, 0);
+     t2 = time_mult(x, 1);
+     printf("%d: %9llu %9llu, %9llu\n", x, t1, t2, t2 - t1);
+     if (t2 < t1) break;
+  }
+  y = x;
+
+  for (x = 8; ; x += 2) { 
+     t1 = time_sqr(x, 0);
+     t2 = time_sqr(x, 1);
+     printf("%d: %9llu %9llu, %9llu\n", x, t1, t2, t2 - t1);
+     if (t2 < t1) break;
+  }
+  printf("KARATSUBA_MUL_CUTOFF = %d\n", y);
+  printf("KARATSUBA_SQR_CUTOFF = %d\n", x);
+
+  return 0;
+}