[vm/compiler] Fix for flaky crash in CallSpecializer::ReplaceWithInstanceOf

There were rare crashes

../../runtime/vm/compiler/call_specializer.cc: 1393: error: expected: call->MatchesCoreName(Symbols::_simpleInstanceOf())
version=2.3.0-edge.796ebc6069bde3a59475a9b45075f49e50b0cc34 (Thu May 9 09:38:28 2019 -0700) on "linux_x64"
thread=82540, isolate=vm-service(0x558748c5d200)
  pc 0x000055874635dd6c fp 0x00007fa94dd3bf30 dart::Profiler::DumpStackTrace(void*)
  pc 0x0000558745f90332 fp 0x00007fa94dd3c010 dart::Assert::Fail(char const*, ...)
  pc 0x000055874653909b fp 0x00007fa94dd3c0a0 dart::CallSpecializer::ReplaceWithInstanceOf(dart::InstanceCallInstr*)
  pc 0x0000558746496ed6 fp 0x00007fa94dd3c0f0 dart::FlowGraphVisitor::VisitBlocks()

when running

tools/test.py --repeat 5000 -n dartkb-mixed-linux-debug-x64 language_2/null_test

at the rate ~1-3 crashes per 30,000 test cases.

The problem is that in function

bool InstanceCallInstr::MatchesCoreName(const String& name) {
  return function_name().raw() == Library::PrivateCoreLibName(name).raw();
}

'function_name().raw()' is evaluated before PrivateCoreLibName(name) is called
and saved in a temporary (register). PrivateCoreLibName may trigger GC and
relocate objects. In such case, 'PrivateCoreLibName(name).raw()' results in a
moved object, which is compared to a stale object address.

This CL fixes InstanceCallInstr::MatchesCoreName and other similar places
by introducing Library::IsPrivateCoreLibName, which is also a little bit more
efficient as it avoids extra symbol table lookup.

Change-Id: I4dc91c586b0c595a3e85d6da13b98fc2248fb8fd
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/102120
Commit-Queue: Alexander Markov <alexmarkov@google.com>
Reviewed-by: Aart Bik <ajcbik@google.com>
4 files changed
tree: 03c6216d178e52265f300b4f35a237aac9ab7ffa
  1. .github/
  2. build/
  3. client/
  4. docs/
  5. pkg/
  6. runtime/
  7. samples/
  8. samples-dev/
  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. .packages
  21. .vpython
  22. AUTHORS
  23. BUILD.gn
  24. CHANGELOG.md
  25. codereview.settings
  26. CONTRIBUTING.md
  27. DEPS
  28. LICENSE
  29. PATENTS
  30. PRESUBMIT.py
  31. README.dart-sdk
  32. README.md
  33. WATCHLISTS
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