--- a/etc/tune.c	Sun Dec 19 11:33:56 2004 +0000
+++ b/etc/tune.c	Fri May 06 08:59:30 2005 +0000
@@ -10,13 +10,44 @@
  */
 #define TIMES (1UL<<14UL)
 
+/* RDTSC from Scott Duplichan */
+static ulong64 TIMFUNC (void)
+   {
+   #if defined __GNUC__
+      #if defined(__i386__) || defined(__x86_64__)
+         unsigned long long a;
+         __asm__ __volatile__ ("rdtsc\nmovl %%eax,%0\nmovl %%edx,4+%0\n"::"m"(a):"%eax","%edx");
+         return a;
+      #else /* gcc-IA64 version */
+         unsigned long result;
+         __asm__ __volatile__("mov %0=ar.itc" : "=r"(result) :: "memory");
+         while (__builtin_expect ((int) result == -1, 0))
+         __asm__ __volatile__("mov %0=ar.itc" : "=r"(result) :: "memory");
+         return result;
+      #endif
+
+   // Microsoft and Intel Windows compilers
+   #elif defined _M_IX86
+     __asm rdtsc
+   #elif defined _M_AMD64
+     return __rdtsc ();
+   #elif defined _M_IA64
+     #if defined __INTEL_COMPILER
+       #include <ia64intrin.h>
+     #endif
+      return __getReg (3116);
+   #else
+     #error need rdtsc function for this build
+   #endif
+   }
+
 
 #ifndef X86_TIMER
 
 /* generic ISO C timer */
-ulong64 __T;
-void t_start(void) { __T = clock(); }
-ulong64 t_read(void) { return clock() - __T; }
+ulong64 LBL_T;
+void t_start(void) { LBL_T = TIMFUNC(); }
+ulong64 t_read(void) { return TIMFUNC() - LBL_T; }
 
 #else
 extern void t_start(void);