[heap] Enforce size checks in allocation stats.

src/heap/spaces.h

 // Copyright 2011 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.
 
 #ifndef V8_HEAP_SPACES_H_
 #define V8_HEAP_SPACES_H_
 
 #include "src/allocation.h"
 #include "src/atomic-utils.h"
 #include "src/base/atomicops.h"
@@ skipping 1526 matching lines @@
 
   // Reset the allocation statistics (i.e., available = capacity with no wasted
   // or allocated bytes).
   void Reset() {
     size_ = 0;
   }
 
   // Accessors for the allocation statistics.
   intptr_t Capacity() { return capacity_; }
   intptr_t MaxCapacity() { return max_capacity_; }
-  intptr_t Size() { return size_; }
+  intptr_t Size() {
+    CHECK_GE(size_, 0);
+    return size_;
+  }
 
   // Grow the space by adding available bytes.  They are initially marked as
   // being in use (part of the size), but will normally be immediately freed,
   // putting them on the free list and removing them from size_.
   void ExpandSpace(int size_in_bytes) {
     capacity_ += size_in_bytes;
     size_ += size_in_bytes;
     if (capacity_ > max_capacity_) {
       max_capacity_ = capacity_;
     }
-    DCHECK(size_ >= 0);
+    CHECK(size_ >= 0);
   }
 
   // Shrink the space by removing available bytes.  Since shrinking is done
   // during sweeping, bytes have been marked as being in use (part of the size)
   // and are hereby freed.
   void ShrinkSpace(int size_in_bytes) {
     capacity_ -= size_in_bytes;
     size_ -= size_in_bytes;
-    DCHECK(size_ >= 0);
+    CHECK(size_ >= 0);
   }
 
   // Allocate from available bytes (available -> size).
   void AllocateBytes(intptr_t size_in_bytes) {
     size_ += size_in_bytes;
-    DCHECK(size_ >= 0);
+    CHECK(size_ >= 0);
   }
 
   // Free allocated bytes, making them available (size -> available).
   void DeallocateBytes(intptr_t size_in_bytes) {
     size_ -= size_in_bytes;
-    DCHECK_GE(size_, 0);
+    CHECK_GE(size_, 0);
   }
 
   // Merge {other} into {this}.
   void Merge(const AllocationStats& other) {
     capacity_ += other.capacity_;
     size_ += other.size_;
     if (other.max_capacity_ > max_capacity_) {
       max_capacity_ = other.max_capacity_;
     }
+    CHECK_GE(size_, 0);
   }
 
   void DecreaseCapacity(intptr_t size_in_bytes) {
     capacity_ -= size_in_bytes;
-    DCHECK_GE(capacity_, 0);
-    DCHECK_GE(capacity_, size_);
+    CHECK_GE(capacity_, 0);
+    CHECK_GE(capacity_, size_);
   }
 
   void IncreaseCapacity(intptr_t size_in_bytes) { capacity_ += size_in_bytes; }
 
  private:
   // |capacity_|: The number of object-area bytes (i.e., not including page
   // bookkeeping structures) currently in the space.
   intptr_t capacity_;
 
   // |max_capacity_|: The maximum capacity ever observed.
@@ skipping 1519 matching lines @@
     count = 0;
   }
   // Must be small, since an iteration is used for lookup.
   static const int kMaxComments = 64;
 };
 #endif
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_HEAP_SPACES_H_