Drop OS::IsOutsideAllocatedSpace() and move the tracking to the MemoryAllocator.

src/platform-cygwin.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 34 matching lines @@
 #include "platform.h"
 #include "simulator.h"
 #include "v8threads.h"
 #include "vm-state-inl.h"
 #include "win32-headers.h"
 
 namespace v8 {
 namespace internal {
 
 
-static Mutex* limit_mutex = NULL;
-
-
 const char* OS::LocalTimezone(double time) {
   if (std::isnan(time)) return "";
   time_t tv = static_cast<time_t>(floor(time/msPerSecond));
   struct tm* t = localtime(&tv);
   if (NULL == t) return "";
   return tzname[0];  // The location of the timezone string on Cygwin.
 }
 
 
 double OS::LocalTimeOffset() {
   // On Cygwin, struct tm does not contain a tm_gmtoff field.
   time_t utc = time(NULL);
   ASSERT(utc != -1);
   struct tm* loc = localtime(&utc);
   ASSERT(loc != NULL);
   // time - localtime includes any daylight savings offset, so subtract it.
   return static_cast<double>((mktime(loc) - utc) * msPerSecond -
                              (loc->tm_isdst > 0 ? 3600 * msPerSecond : 0));
 }
 
 
-// We keep the lowest and highest addresses mapped as a quick way of
-// determining that pointers are outside the heap (used mostly in assertions
-// and verification).  The estimate is conservative, i.e., not all addresses in
-// 'allocated' space are actually allocated to our heap.  The range is
-// [lowest, highest), inclusive on the low and and exclusive on the high end.
-static void* lowest_ever_allocated = reinterpret_cast<void*>(-1);
-static void* highest_ever_allocated = reinterpret_cast<void*>(0);
-
-
-static void UpdateAllocatedSpaceLimits(void* address, int size) {
-  ASSERT(limit_mutex != NULL);
-  LockGuard<Mutex> lock_guard(limit_mutex);
-
-  lowest_ever_allocated = Min(lowest_ever_allocated, address);
-  highest_ever_allocated =
-      Max(highest_ever_allocated,
-          reinterpret_cast<void*>(reinterpret_cast<char*>(address) + size));
-}
-
-
-bool OS::IsOutsideAllocatedSpace(void* address) {
-  return address < lowest_ever_allocated || address >= highest_ever_allocated;
-}
-
-
 void* OS::Allocate(const size_t requested,
                    size_t* allocated,
                    bool is_executable) {
   const size_t msize = RoundUp(requested, sysconf(_SC_PAGESIZE));
   int prot = PROT_READ | PROT_WRITE | (is_executable ? PROT_EXEC : 0);
   void* mbase = mmap(NULL, msize, prot, MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
   if (mbase == MAP_FAILED) {
     LOG(ISOLATE, StringEvent("OS::Allocate", "mmap failed"));
     return NULL;
   }
   *allocated = msize;
-  UpdateAllocatedSpaceLimits(mbase, msize);
   return mbase;
 }
 
 
 void OS::DumpBacktrace() {
   // Currently unsupported.
 }
 
 
 class PosixMemoryMappedFile : public OS::MemoryMappedFile {
@@ skipping 232 matching lines @@
 void* VirtualMemory::ReserveRegion(size_t size) {
   return RandomizedVirtualAlloc(size, MEM_RESERVE, PAGE_NOACCESS);
 }
 
 
 bool VirtualMemory::CommitRegion(void* base, size_t size, bool is_executable) {
   int prot = is_executable ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;
   if (NULL == VirtualAlloc(base, size, MEM_COMMIT, prot)) {
     return false;
   }
-
-  UpdateAllocatedSpaceLimits(base, static_cast<int>(size));
   return true;
 }
 
 
 bool VirtualMemory::Guard(void* address) {
   if (NULL == VirtualAlloc(address,
                            OS::CommitPageSize(),
                            MEM_COMMIT,
                            PAGE_READONLY | PAGE_GUARD)) {
     return false;
@@ skipping 19 matching lines @@
 
 
 void OS::SetUp() {
   // Seed the random number generator.
   // Convert the current time to a 64-bit integer first, before converting it
   // to an unsigned. Going directly can cause an overflow and the seed to be
   // set to all ones. The seed will be identical for different instances that
   // call this setup code within the same millisecond.
   uint64_t seed = static_cast<uint64_t>(TimeCurrentMillis());
   srandom(static_cast<unsigned int>(seed));
-  limit_mutex = new Mutex();
 }
 
 
 void OS::TearDown() {
-  delete limit_mutex;
 }
 
 
 } }  // namespace v8::internal