Made zone segments aligned in memory and included a pointer to the zone in the header. Larger objec…

src/base/accounting-allocator.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "src/base/accounting-allocator.h"
 
 #include <cstdlib>
 
 #if V8_LIBC_BIONIC
 #include <malloc.h>  // NOLINT
 #endif
 
 namespace v8 {
 namespace base {
 
 void* AccountingAllocator::Allocate(size_t bytes) {
   void* memory = malloc(bytes);
   if (memory) {
-    AtomicWord current =
-        NoBarrier_AtomicIncrement(&current_memory_usage_, bytes);
-    AtomicWord max = NoBarrier_Load(&max_memory_usage_);
-    while (current > max) {
-      max = NoBarrier_CompareAndSwap(&max_memory_usage_, max, current);
-    }
+    ChangeCurrentMemoryUsage(bytes);
   }
   return memory;
 }
 
 void AccountingAllocator::Free(void* memory, size_t bytes) {
   free(memory);
-  NoBarrier_AtomicIncrement(&current_memory_usage_,
-                            -static_cast<AtomicWord>(bytes));
+  ChangeCurrentMemoryUsage(-static_cast<int64_t>(bytes));
+}
+
+void AccountingAllocator::ChangeCurrentMemoryUsage(const int64_t bytes) {
+  AtomicWord current = NoBarrier_AtomicIncrement(&current_memory_usage_, bytes);
+  AtomicWord max = NoBarrier_Load(&max_memory_usage_);
+  if (bytes > 0) {
+    while (current > max) {
+      max = NoBarrier_CompareAndSwap(&max_memory_usage_, max, current);
+    }
+  }
 }
 
 size_t AccountingAllocator::GetCurrentMemoryUsage() const {
   return NoBarrier_Load(&current_memory_usage_);
 }
 
 size_t AccountingAllocator::GetMaxMemoryUsage() const {
   return NoBarrier_Load(&max_memory_usage_);
 }
 
 }  // namespace base
 }  // namespace v8