Replace OS::MemCopy with OS::MemMove (just as fast but more flexible).

src/atomicops_internals_x86_gcc.cc

Index: src/atomicops_internals_x86_gcc.cc
diff --git a/src/atomicops_internals_x86_gcc.cc b/src/atomicops_internals_x86_gcc.cc
index 181c2024788f86092821ff09b0543588ad217cc6..b5078cf4a50ba69308808ea36cbd89cdfbf64f74 100644
--- a/src/atomicops_internals_x86_gcc.cc
+++ b/src/atomicops_internals_x86_gcc.cc
@@ -31,6 +31,7 @@
 #include <string.h>
 
 #include "atomicops.h"
+#include "platform.h"
 
 // This file only makes sense with atomicops_internals_x86_gcc.h -- it
 // depends on structs that are defined in that file.  If atomicops.h
@@ -84,9 +85,9 @@ void AtomicOps_Internalx86CPUFeaturesInit() {
   // Get vendor string (issue CPUID with eax = 0)
   cpuid(eax, ebx, ecx, edx, 0);
   char vendor[13];
-  memcpy(vendor, &ebx, 4);
-  memcpy(vendor + 4, &edx, 4);
-  memcpy(vendor + 8, &ecx, 4);
+  v8::internal::OS::MemCopy(vendor, &ebx, 4);
+  v8::internal::OS::MemCopy(vendor + 4, &edx, 4);
+  v8::internal::OS::MemCopy(vendor + 8, &ecx, 4);
   vendor[12] = 0;
 
   // get feature flags in ecx/edx, and family/model in eax