[flang][cuda] Delay descriptor alloc when addressed reused on host/device (#220534)

CSE can share one fir.coordinate_of between the host-association capture
store and a later fir.load. Treating that coordinate_of as a real use
made cuf-alloc-delay think the movable group depended on an operand at
the sink point, so the device descriptor stayed at function entry and
cudaMallocManaged ran before cudaSetDevice.

Count only users of the slot address that actually read it. Stores that
populate the tuple still sink with the allocation group.

GitOrigin-RevId: 81bf35d75a2925ff57a470b7a54c5d3730ade165
2 files changed
tree: 5561cc88393a26d732e31c4fea08d6e81c5451d7
  1. cmake/
  2. docs/
  3. examples/
  4. include/
  5. lib/
  6. test/
  7. tools/
  8. unittests/
  9. .clang-format
  10. .clang-tidy
  11. .drone.star
  12. .gitignore
  13. CMakeLists.txt
  14. LICENSE.TXT
  15. Maintainers.md
  16. README.md
README.md

Flang

Flang is a ground-up implementation of a Fortran front end written in modern C++. It started off as the f18 project (https://github.com/flang-compiler/f18) with an aim to replace the previous flang project (https://github.com/flang-compiler/flang) and address its various deficiencies. F18 was subsequently accepted into the LLVM project and rechristened as Flang.

Please note that flang is not ready yet for production usage.

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Read more about flang in the docs directory. Start with the compiler overview.

To better understand Fortran as a language and the specific grammar accepted by flang, read Fortran For C Programmers and flang's specifications of the Fortran grammar and the OpenMP grammar.

Treatment of language extensions is covered in this document.

To understand the compilers handling of intrinsics, see the discussion of intrinsics.

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Consult the Getting Started with Flang for information on building and running flang.