Properly implement OS::GetRandomMmapAddr() for Win32.

src/platform-win32.cc

 // Copyright 2012 the V8 project authors. 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
@@ skipping 874 matching lines @@
   static size_t allocate_alignment = 0;
   if (allocate_alignment == 0) {
     SYSTEM_INFO info;
     GetSystemInfo(&info);
     allocate_alignment = info.dwAllocationGranularity;
   }
   return allocate_alignment;
 }
 
 
-static void* GetRandomAddr() {
+void* OS::GetRandomMmapAddr() {
   Isolate* isolate = Isolate::UncheckedCurrent();
   // Note that the current isolate isn't set up in a call path via
   // CpuFeatures::Probe. We don't care about randomization in this case because
   // the code page is immediately freed.
   if (isolate != NULL) {
     // The address range used to randomize RWX allocations in OS::Allocate
     // Try not to map pages into the default range that windows loads DLLs
     // Use a multiple of 64k to prevent committing unused memory.
     // Note: This does not guarantee RWX regions will be within the
     // range kAllocationRandomAddressMin to kAllocationRandomAddressMax
@@ skipping 1084 matching lines @@
   limit_mutex = CreateMutex();
 }
 
 
 void OS::TearDown() {
   delete limit_mutex;
 }
 
 
 } }  // namespace v8::internal