Initial commit.

examples/timing.h

@@ -0,0 +1,67 @@
+/*
+  Copyright (c) 2010-2011, Intel Corporation
+  All rights reserved.
+
+  Redistribution and use in source and binary forms, with or without
+  modification, are permitted provided that the following conditions are
+  met:
+
+    * Redistributions of source code must retain the above copyright
+      notice, this list of conditions and the following disclaimer.
+
+    * Redistributions in binary form must reproduce the above copyright
+      notice, this list of conditions and the following disclaimer in the
+      documentation and/or other materials provided with the distribution.
+
+    * Neither the name of Intel Corporation nor the names of its
+      contributors may be used to endorse or promote products derived from
+      this software without specific prior written permission.
+
+
+   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS
+   IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
+   TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
+   PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER
+   OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
+   EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
+   PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
+   PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
+   LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
+   NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
+   SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.  
+*/
+
+#include <stdint.h>
+
+
+#ifdef WIN32
+#include <windows.h>
+#define rdtsc __rdtsc
+#else
+extern "C" {
+    __inline__ uint64_t rdtsc() {
+        uint32_t low, high;
+        __asm__ __volatile__ (
+            "xorl %%eax,%%eax \n    cpuid"
+            ::: "%rax", "%rbx", "%rcx", "%rdx" );
+        __asm__ __volatile__ (
+                              "rdtsc" : "=a" (low), "=d" (high));
+        return (uint64_t)high << 32 | low;
+    }
+}
+#endif            
+            
+static uint64_t start, end;
+
+static inline void reset_and_start_timer()
+{
+    start = rdtsc();
+}
+
+/* Returns the number of millions of elapsed processor cycles since the
+   last reset_and_start_timer() call. */
+static inline double get_elapsed_mcycles()
+{
+    end = rdtsc();
+    return (end-start) / (1024. * 1024.);
+}