wtf/CheckedArithmetic.h delegates to base/numerics/safe_math.h.

third_party/WebKit/Source/core/html/HTMLCanvasElement.cpp

 /*
  * Copyright (C) 2004, 2006, 2007 Apple Inc. All rights reserved.
  * Copyright (C) 2007 Alp Toker <alp@atoker.com>
  * Copyright (C) 2010 Torch Mobile (Beijing) Co. Ltd. All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
@@ skipping 49 matching lines @@
 #include "platform/graphics/CanvasMetrics.h"
 #include "platform/graphics/ExpensiveCanvasHeuristicParameters.h"
 #include "platform/graphics/ImageBuffer.h"
 #include "platform/graphics/RecordingImageBufferSurface.h"
 #include "platform/graphics/StaticBitmapImage.h"
 #include "platform/graphics/UnacceleratedImageBufferSurface.h"
 #include "platform/graphics/gpu/AcceleratedImageBufferSurface.h"
 #include "platform/transforms/AffineTransform.h"
 #include "public/platform/Platform.h"
 #include "public/platform/WebTraceLocation.h"
+#include "wtf/CheckedNumeric.h"
 #include <math.h>
 #include <v8.h>
 
 namespace blink {
 
 using namespace HTMLNames;
 
 namespace {
 
 // These values come from the WhatWG spec.
@@ skipping 740 matching lines @@
             // non-displayed state) and three (triple-buffered animations).
             // Adding 2 is a pessimistic but relevant estimate.
             // Note: These buffers might be allocated in GPU memory.
             bufferCount += 2;
         }
     }
     if (m_copiedImage)
         bufferCount++;
 
     // Four bytes per pixel per buffer.
-    Checked<intptr_t, RecordOverflow> checkedExternallyAllocatedMemory = 4 * bufferCount;
+    CheckedNumeric<intptr_t> checkedExternallyAllocatedMemory = 4 * bufferCount;
     if (is3D())
         checkedExternallyAllocatedMemory += m_context->externallyAllocatedBytesPerPixel();
 
     checkedExternallyAllocatedMemory *= width();
     checkedExternallyAllocatedMemory *= height();
-    intptr_t externallyAllocatedMemory;
-    if (checkedExternallyAllocatedMemory.safeGet(externallyAllocatedMemory) == CheckedState::DidOverflow)
-        externallyAllocatedMemory = std::numeric_limits<intptr_t>::max();
+    intptr_t externallyAllocatedMemory = checkedExternallyAllocatedMemory.ValueOrDefault(std::numeric_limits<intptr_t>::max());
 
     // Subtracting two intptr_t that are known to be positive will never underflow.
     v8::Isolate::GetCurrent()->AdjustAmountOfExternalAllocatedMemory(externallyAllocatedMemory - m_externallyAllocatedMemory);
     m_externallyAllocatedMemory = externallyAllocatedMemory;
 }
 
 SkCanvas* HTMLCanvasElement::drawingCanvas() const
 {
     return buffer() ? m_imageBuffer->canvas() : nullptr;
 }
@@ skipping 231 matching lines @@
 }
 
 std::pair<Element*, String> HTMLCanvasElement::getControlAndIdIfHitRegionExists(const LayoutPoint& location)
 {
     if (m_context && m_context->is2d())
         return m_context->getControlAndIdIfHitRegionExists(location);
     return std::make_pair(nullptr, String());
 }
 
 } // namespace blink