shithub: libvpx

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Add the 64-bit CPU cycle count utility function

Change-Id: Ie87245bbdf5735bc9729199eeb07899d81dbf267

--- a/vpx_ports/x86.h

+++ b/vpx_ports/x86.h

@@ -216,6 +216,11 @@

 unsigned __int64 __rdtsc(void);

 #pragma intrinsic(__rdtsc)

 #endif

+// Note:

+//  32-bit CPU cycle counter is light-weighted for most function performance

+//  measurement. For large function (CPU time > a couple of seconds), 64-bit

+//  counter should be used.

+// 32-bit CPU cycle counter

 static INLINE unsigned int

 x86_readtsc(void) {

 #if defined(__GNUC__) && __GNUC__

@@ -234,7 +239,25 @@

 #endif

 #endif

 }

-

+// 64-bit CPU cycle counter

+static INLINE uint64_t

+x86_readtsc64(void) {

+#if defined(__GNUC__) && __GNUC__

+  uint32_t hi, lo;

+  __asm__ __volatile__("rdtsc" : "=a"(lo), "=d"(hi));

+  return ((uint64_t)hi << 32) | lo;

+#elif defined(__SUNPRO_C) || defined(__SUNPRO_CC)

+  uint_t hi, lo;

+  asm volatile("rdtsc\n\t" : "=a"(lo), "=d"(hi));

+  return ((uint64_t)hi << 32) | lo;

+#else

+#if ARCH_X86_64

+  return (uint64_t)__rdtsc();

+#else

+  __asm  rdtsc;

+#endif

+#endif

+}

 #if defined(__GNUC__) && __GNUC__

 #define x86_pause_hint()\