[clang][dataflow] Handle more glvalue cases of the ConditionalOperator transfer (#168994)

In the dataflow framework, the builtin transfer function currently only
handles the GLValue result case of ConditionalOperator when the
true and false expression StorageLocations are exactly the same.

Ideally / we have wanted to introduce alias sets to handle when the Locs
are different. However, that is a larger change to the framework
(and we may need to introduce weak updates).

For now, do something simpler to at least handle when the GLValue is
immediately cast to an RValue, by making up a distinct StorageLocation
that holds the join of the true and false expression values (when not a
record). This seems like the most common case, so seems worth covering.
The case when an LValue is needed and can be updated later (and
thus needs a link to the original storage locations) seems more rare,
and we currently do not handle such updates either, so this intermediate
step is no different (for that case).
2 files changed
tree: 57e14400f0b0c0156bf7fa38072fecd3eb8af488
  1. .ci/
  2. .github/
  3. bolt/
  4. clang/
  5. clang-tools-extra/
  6. cmake/
  7. compiler-rt/
  8. cross-project-tests/
  9. flang/
  10. flang-rt/
  11. libc/
  12. libclc/
  13. libcxx/
  14. libcxxabi/
  15. libsycl/
  16. libunwind/
  17. lld/
  18. lldb/
  19. llvm/
  20. llvm-libgcc/
  21. mlir/
  22. offload/
  23. openmp/
  24. orc-rt/
  25. polly/
  26. runtimes/
  27. third-party/
  28. utils/
  29. .clang-format
  30. .clang-format-ignore
  31. .clang-tidy
  32. .git-blame-ignore-revs
  33. .gitattributes
  34. .gitignore
  35. .mailmap
  36. CODE_OF_CONDUCT.md
  37. CONTRIBUTING.md
  38. LICENSE.TXT
  39. pyproject.toml
  40. README.md
  41. SECURITY.md
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