1 files changed, 74 insertions, 1 deletions

diff --git a/mps/code/eventcom.h b/mps/code/eventcom.h
index 1bf0a67c311..64fe935edde 100644
--- a/mps/code/eventcom.h
+++ b/mps/code/eventcom.h
@@ -10,11 +10,84 @@
 #define eventcom_h
 
 #include <limits.h>
-#include "config.h" /* for EventClock */
 #include "mpmtypes.h" /* for Word */
 #include "eventdef.h"
 
 
+/* EVENT_CLOCK -- fast event timestamp clock
+ *
+ * On platforms that support it, we want to stamp events with a very cheap
+ * and fast high-resolution timer.
+ */
+
+/* http://msdn.microsoft.com/en-US/library/twchhe95%28v=vs.100%29.aspx */
+#if (defined(MPS_ARCH_I3) || defined(MPS_ARCH_I6)) && defined(MPS_BUILD_MV)
+
+#pragma intrinsic(__rdtsc)
+
+typedef unsigned __int64 EventClock;
+
+#define EVENT_CLOCK(lvalue) \
+  BEGIN \
+    (lvalue) = __rdtsc(); \
+  END
+
+#define EVENT_CLOCK_PRINT(stream, clock) fprintf(stream, "%llu", clock)
+
+/* http://clang.llvm.org/docs/LanguageExtensions.html#builtins */
+#elif defined(MPS_BUILD_LL)
+
+#if __has_builtin(__builtin_readcyclecounter)
+
+typedef unsigned long long EventClock;
+
+#define EVENT_CLOCK(lvalue) \
+  BEGIN \
+    (lvalue) = __builtin_readcyclecounter(); \
+  END
+
+#define EVENT_CLOCK_PRINT(stream, clock) fprintf(stream, "%llu", clock)
+
+#endif /* __has_builtin(__builtin_readcyclecounter) */
+
+#endif
+
+/* Assemble the rdtsc instruction */
+#if !defined(EVENT_CLOCK) && \
+    (defined(MPS_ARCH_I3) || defined(MPS_ARCH_I6)) && \
+      (defined(MPS_BUILD_GC) || defined(MPS_BUILD_LL))
+
+/* Use __extension__ to enable use of a 64-bit type on 32-bit pedantic GCC */
+__extension__ typedef unsigned long long EventClock;
+
+#define EVENT_CLOCK(lvalue) \
+  BEGIN \
+    unsigned _l, _h; \
+    __asm__ __volatile__("rdtsc" : "=a"(_l), "=d"(_h)); \
+    (lvalue) = ((EventClock)_h << 32) | _l; \
+  END
+
+#define EVENT_CLOCK_PRINT(stream, clock) \
+  fprintf(stream, "%lu", (unsigned long)clock) /* FIXME: Should be %llu */
+
+#endif /* Intel, GCC or Clang */
+
+/* no fast clock, use plinth, probably from the C library */
+#ifndef EVENT_CLOCK
+
+typedef Word EventClock;
+
+#define EVENT_CLOCK(lvalue) \
+  BEGIN \
+    (lvalue) = mps_clock(); \
+  END
+
+#define EVENT_CLOCK_PRINT(stream, clock) \
+  fprintf(stream, "%llu", (unsigned long long)clock)
+
+#endif
+
+
 /* Types for event fields */
 
 typedef unsigned short EventCode;