Simplify VirtualMemory by removing unused ReserveAligned method.

runtime/vm/virtual_memory_win.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_OS_WINDOWS)
 
 #include "vm/virtual_memory.h"
 
 #include "platform/assert.h"
 #include "vm/os.h"
 
 namespace dart {
 
 uword VirtualMemory::page_size_ = 0;
 
 
 void VirtualMemory::InitOnce() {
   SYSTEM_INFO info;
   GetSystemInfo(&info);
   page_size_ = info.dwPageSize;
 }
 
 
-VirtualMemory* VirtualMemory::Reserve(intptr_t size) {
+VirtualMemory* VirtualMemory::ReserveInternal(intptr_t size) {
   void* address = VirtualAlloc(NULL, size, MEM_RESERVE, PAGE_NOACCESS);
   if (address == NULL) {
     return NULL;
   }
   MemoryRegion region(address, size);
   return new VirtualMemory(region, address);
 }
 
 
 VirtualMemory::~VirtualMemory() {
-  if (size() == 0) {
+  if (reserved_size_ == 0) {
     return;
   }
-
-  // Since sub-segments are not freed, free the entire virtual segment
-  // here by passing the originally reserved pointer to VirtualFree.
-  ASSERT(reserved_pointer_ != NULL);
-  if (VirtualFree(reserved_pointer_, 0, MEM_RELEASE) == 0) {
+  if (VirtualFree(address(), 0, MEM_RELEASE) == 0) {
     FATAL("VirtualFree failed");
   }
 }
 
 
-void VirtualMemory::FreeSubSegment(void* address, intptr_t size) {
+bool VirtualMemory::FreeSubSegment(void* address, intptr_t size) {
   // On Windows only the entire segment returned by VirtualAlloc
   // can be freed. Therefore we will have to waste these unused
   // virtual memory sub-segments.
+  return false;
 }
 
 
 bool VirtualMemory::Commit(uword addr, intptr_t size, bool executable) {
   ASSERT(Contains(addr));
   ASSERT(Contains(addr + size) || (addr + size == end()));
   int prot = executable ? PAGE_EXECUTE_READWRITE : PAGE_READWRITE;
   if (VirtualAlloc(address(), size, MEM_COMMIT, prot) == NULL) {
     return false;
   }
@@ skipping 27 matching lines @@
   bool result = VirtualProtect(reinterpret_cast<void*>(page_address),
                         end_address - page_address,
                         prot,
                         &old_prot);
   return result;
 }
 
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_WINDOWS)