Merge experimental/gc branch to the bleeding_edge.

src/platform-win32.cc

 // Copyright 2011 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 1379 matching lines @@
 #endif
 }
 
 
 void OS::ReleaseStore(volatile AtomicWord* ptr, AtomicWord value) {
   MemoryBarrier();
   *ptr = value;
 }
 
 
+VirtualMemory::VirtualMemory() : address_(NULL), size_(0) { }
+
+
+VirtualMemory::VirtualMemory(size_t size)
+    : address_(ReserveRegion(size)), size_(size) { }
+
+
+VirtualMemory::VirtualMemory(size_t size, size_t alignment)
+    : address_(NULL), size_(0) {
+  ASSERT(IsAligned(alignment, static_cast<intptr_t>(OS::AllocateAlignment())));
+  size_t request_size = RoundUp(size + alignment,
+                                static_cast<intptr_t>(OS::AllocateAlignment()));
+  void* address = ReserveRegion(request_size);
+  if (address == NULL) return;
+  Address base = RoundUp(static_cast<Address>(address), alignment);
+  // Try reducing the size by freeing and then reallocating a specific area.
+  ReleaseRegion(address, request_size);
+  address = VirtualAlloc(base, size, MEM_RESERVE, PAGE_NOACCESS);
+  if (address != NULL) {
+    request_size = size;
+    ASSERT(base == static_cast<Address>(address));
+  } else {
+    // Resizing failed, just go with a bigger area.
+    address = ReserveRegion(request_size);
+    if (address == NULL) return;
+  }
+  address_ = address;
+  size_ = request_size;
+}
+
+
+VirtualMemory::~VirtualMemory() {
+  if (IsReserved()) {
+    bool result = ReleaseRegion(address_, size_);
+    ASSERT(result);
+    USE(result);
+  }
+}
+
+
 bool VirtualMemory::IsReserved() {
   return address_ != NULL;
 }
 
 
-VirtualMemory::VirtualMemory(size_t size) {
-  address_ = VirtualAlloc(NULL, size, MEM_RESERVE, PAGE_NOACCESS);
-  size_ = size;
-}
-
-
-VirtualMemory::~VirtualMemory() {
-  if (IsReserved()) {
-    if (0 == VirtualFree(address(), 0, MEM_RELEASE)) address_ = NULL;
-  }
+void VirtualMemory::Reset() {
+  address_ = NULL;
+  size_ = 0;
 }
 
 
 bool VirtualMemory::Commit(void* address, size_t size, bool is_executable) {
-  int prot = is_executable ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;
-  if (NULL == VirtualAlloc(address, size, MEM_COMMIT, prot)) {
-    return false;
+  if (CommitRegion(address, size, is_executable)) {
+    UpdateAllocatedSpaceLimits(address, static_cast<int>(size));
+    return true;
   }
-
-  UpdateAllocatedSpaceLimits(address, static_cast<int>(size));
-  return true;
+  return false;
 }
 
 
 bool VirtualMemory::Uncommit(void* address, size_t size) {
   ASSERT(IsReserved());
-  return VirtualFree(address, size, MEM_DECOMMIT) != false;
+  return UncommitRegion(address, size);
 }
 
 
+void* VirtualMemory::ReserveRegion(size_t size) {
+  return VirtualAlloc(NULL, 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::UncommitRegion(void* base, size_t size) {
+  return VirtualFree(base, size, MEM_DECOMMIT) != 0;
+}
+
+
+bool VirtualMemory::ReleaseRegion(void* base, size_t size) {
+  return VirtualFree(base, 0, MEM_RELEASE) != 0;
+}
+
+
+
 // ----------------------------------------------------------------------------
 // Win32 thread support.
 
 // Definition of invalid thread handle and id.
 static const HANDLE kNoThread = INVALID_HANDLE_VALUE;
 
 // Entry point for threads. The supplied argument is a pointer to the thread
 // object. The entry function dispatches to the run method in the thread
 // object. It is important that this function has __stdcall calling
 // convention.
@@ skipping 525 matching lines @@
 
 
 void Sampler::Stop() {
   ASSERT(IsActive());
   SamplerThread::RemoveActiveSampler(this);
   SetActive(false);
 }
 
 
 } }  // namespace v8::internal