[vm] Fix deallocation of compressed heap

When VirtualMemory object for the whole compressed pointers heap
region is destroyed in VirtualMemory::~VirtualMemory(), it tests
if the reservation address belongs to a compressed heap via

  VirtualMemoryCompressedHeap::Contains(reserved_.pointer())

If the heap region happens to be reserved at the 4GB aligned address
by the O/S, then reservation address would match base address of
the compressed pointers heap, and this check would pass and
the whole reserved heap region would be passed to
VirtualMemoryCompressedHeap::Free.

However, the reservation size of the whole heap region is
(8GB - 1 page) which is not aligned to kCompressedPageSize (512K).
This would trigger assertion

  ASSERT(Utils::IsAligned(size, kCompressedPageSize));

inside VirtualMemoryCompressedHeap::Free.

The fix is to detect when the whole compressed heap region is being
destroyed and avoid calling VirtualMemoryCompressedHeap::Free
as the region reserved for the whole heap is not managed by
the compressed heap itself.

TEST=python3 tools/test.py -n vm-win-debug-x64c --repeat 10000 co19/LibTest/typed_data/Uint32List/Uint32List.view_A01_t01
Fixes https://github.com/dart-lang/sdk/issues/51170

Change-Id: Icdf02eb0e2e3f39e435cba76fa647726bb383928
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/352962
Reviewed-by: Ryan Macnak <rmacnak@google.com>
Reviewed-by: Liam Appelbe <liama@google.com>
Commit-Queue: Alexander Markov <alexmarkov@google.com>
2 files changed
tree: e35b6a7847d9c7e7c0443b07a414fc791d9f11cd
  1. .dart_tool/
  2. .github/
  3. benchmarks/
  4. build/
  5. docs/
  6. pkg/
  7. runtime/
  8. samples/
  9. sdk/
  10. tests/
  11. third_party/
  12. tools/
  13. utils/
  14. .clang-format
  15. .gitattributes
  16. .gitconfig
  17. .gitignore
  18. .gn
  19. .mailmap
  20. .style.yapf
  21. AUTHORS
  22. BUILD.gn
  23. CHANGELOG.md
  24. codereview.settings
  25. CONTRIBUTING.md
  26. DEPS
  27. LICENSE
  28. OWNERS
  29. PATENT_GRANT
  30. PRESUBMIT.py
  31. README.dart-sdk
  32. README.md
  33. sdk.code-workspace
  34. sdk_args.gni
  35. SECURITY.md
  36. WATCHLISTS
README.md

Dart

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