SizeLimits.cpp 3.2 KB

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  1. /*
  2. * Copyright (C) 2010 Google Inc. All rights reserved.
  3. *
  4. * Redistribution and use in source and binary forms, with or without
  5. * modification, are permitted provided that the following conditions are
  6. * met:
  7. *
  8. * * Redistributions of source code must retain the above copyright
  9. * notice, this list of conditions and the following disclaimer.
  10. * * Redistributions in binary form must reproduce the above
  11. * copyright notice, this list of conditions and the following disclaimer
  12. * in the documentation and/or other materials provided with the
  13. * distribution.
  14. * * Neither the name of Google Inc. nor the names of its
  15. * contributors may be used to endorse or promote products derived from
  16. * this software without specific prior written permission.
  17. *
  18. * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  19. * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  20. * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  21. * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  22. * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  23. * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  24. * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  25. * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  26. * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  27. * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  28. * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  29. */
  30. #include "config.h"
  31. #include <wtf/Assertions.h>
  32. #include <wtf/OwnPtr.h>
  33. #include <wtf/PassRefPtr.h>
  34. #include <wtf/RefCounted.h>
  35. #include <wtf/RefPtr.h>
  36. #include <wtf/ThreadRestrictionVerifier.h>
  37. #include <wtf/Vector.h>
  38. namespace WTF {
  39. #ifndef NDEBUG
  40. struct SameSizeAsRefCounted {
  41. int a;
  42. bool b;
  43. bool c;
  44. ThreadRestrictionVerifier d;
  45. // The debug version may get bigger.
  46. };
  47. #else
  48. struct SameSizeAsRefCounted {
  49. int a;
  50. // Don't add anything here because this should stay small.
  51. };
  52. #endif
  53. template<typename T, unsigned inlineCapacity>
  54. struct SameSizeAsVectorWithInlineCapacity {
  55. void* bufferPointer;
  56. unsigned capacity;
  57. unsigned size;
  58. AlignedBuffer<inlineCapacity * sizeof(T), WTF_ALIGN_OF(T)> inlineBuffer;
  59. };
  60. COMPILE_ASSERT(sizeof(OwnPtr<int>) == sizeof(int*), OwnPtr_should_stay_small);
  61. COMPILE_ASSERT(sizeof(PassRefPtr<RefCounted<int> >) == sizeof(int*), PassRefPtr_should_stay_small);
  62. COMPILE_ASSERT(sizeof(RefCounted<int>) == sizeof(SameSizeAsRefCounted), RefCounted_should_stay_small);
  63. COMPILE_ASSERT(sizeof(RefCountedCustomAllocated<int>) == sizeof(SameSizeAsRefCounted), RefCountedCustomAllocated_should_stay_small);
  64. COMPILE_ASSERT(sizeof(RefPtr<RefCounted<int> >) == sizeof(int*), RefPtr_should_stay_small);
  65. COMPILE_ASSERT(sizeof(Vector<int, 1>) == sizeof(SameSizeAsVectorWithInlineCapacity<int, 1>), Vector_should_stay_small);
  66. COMPILE_ASSERT(sizeof(Vector<int, 2>) == sizeof(SameSizeAsVectorWithInlineCapacity<int, 2>), Vector_should_stay_small);
  67. COMPILE_ASSERT(sizeof(Vector<int, 3>) == sizeof(SameSizeAsVectorWithInlineCapacity<int, 3>), Vector_should_stay_small);
  68. }