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authorLorry Tar Creator <lorry-tar-importer@lorry>2017-06-27 06:07:23 +0000
committerLorry Tar Creator <lorry-tar-importer@lorry>2017-06-27 06:07:23 +0000
commit1bf1084f2b10c3b47fd1a588d85d21ed0eb41d0c (patch)
tree46dcd36c86e7fbc6e5df36deb463b33e9967a6f7 /Source/WTF/wtf/SizeLimits.cpp
parent32761a6cee1d0dee366b885b7b9c777e67885688 (diff)
downloadWebKitGtk-tarball-master.tar.gz
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+/*
+ * Copyright (C) 2010 Google Inc. 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 with the
+ * distribution.
+ * * Neither the name of Google Inc. nor the names of its
+ * contributors may be used to endorse or promote products derived from
+ * this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ */
+
+#include "config.h"
+
+#include <type_traits>
+#include <utility>
+#include <wtf/Assertions.h>
+#include <wtf/PassRefPtr.h>
+#include <wtf/RefCounted.h>
+#include <wtf/RefPtr.h>
+#include <wtf/Vector.h>
+
+namespace WTF {
+
+#if !defined(NDEBUG) || ENABLE(SECURITY_ASSERTIONS)
+struct SameSizeAsRefCounted {
+ int a;
+ bool b;
+ bool c;
+ // The debug version may get bigger.
+};
+#else
+struct SameSizeAsRefCounted {
+ int a;
+ // Don't add anything here because this should stay small.
+};
+#endif
+
+static_assert(sizeof(PassRefPtr<RefCounted<int>>) == sizeof(int*), "PassRefPtr should stay small!");
+static_assert(sizeof(RefCounted<int>) == sizeof(SameSizeAsRefCounted), "RefCounted should stay small!");
+static_assert(sizeof(RefPtr<RefCounted<int>>) == sizeof(int*), "RefPtr should stay small!");
+
+#if !ASAN_ENABLED
+template<typename T, unsigned inlineCapacity = 0>
+struct SameSizeAsVectorWithInlineCapacity;
+
+template<typename T>
+struct SameSizeAsVectorWithInlineCapacity<T, 0> {
+ void* bufferPointer;
+ unsigned capacity;
+ unsigned size;
+};
+
+template<typename T, unsigned inlineCapacity>
+struct SameSizeAsVectorWithInlineCapacity {
+ SameSizeAsVectorWithInlineCapacity<T, 0> baseCapacity;
+ typename std::aligned_storage<sizeof(T), std::alignment_of<T>::value>::type inlineBuffer[inlineCapacity];
+};
+
+static_assert(sizeof(Vector<int>) == sizeof(SameSizeAsVectorWithInlineCapacity<int>), "Vector should stay small!");
+static_assert(sizeof(Vector<int, 1>) == sizeof(SameSizeAsVectorWithInlineCapacity<int, 1>), "Vector should stay small!");
+static_assert(sizeof(Vector<int, 2>) == sizeof(SameSizeAsVectorWithInlineCapacity<int, 2>), "Vector should stay small!");
+static_assert(sizeof(Vector<int, 3>) == sizeof(SameSizeAsVectorWithInlineCapacity<int, 3>), "Vector should stay small!");
+#endif
+}