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llvm / llvm-project / 81ba006296680c9d62aba12c5e3f083e2f7c595d
commit81ba006296680c9d62aba12c5e3f083e2f7c595d[log] [tgz]
authorFangrui Song <i@maskray.me>Sun Mar 16 16:18:14 2025 -0700
committerGitHub <noreply@github.com>Sun Mar 16 16:18:14 2025 -0700
treea423932f9348e356acb98ef044c79a2f9820010a
parent91328dbae986dfa93cf2acef0a93361fd5ced66d [diff]
[X86] nocf_check: disable tail call

When a function pointer is annotated with
`void (*fptr)(void) __attribute__((nocf_check));`, calling it should use
the NOTRACK prefix, as the callee may not contain an ENDBR.

https://reviews.llvm.org/D41879 implemented NOTRACK variants for
X86ISD::CALL and ISD::BRIND but not for TCRETURN. Given that there are
so many tail call variants (e.g. conditional tailcall
https://reviews.llvm.org/D29856), let's just disable tailcall.
While nocf_check has some uses within the Linux kernel, it isn't a
popular attribute.

Fix #91228

Pull Request: https://github.com/llvm/llvm-project/pull/131487
2 files changed
tree: a423932f9348e356acb98ef044c79a2f9820010a
  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. libunwind/
  16. lld/
  17. lldb/
  18. llvm/
  19. llvm-libgcc/
  20. mlir/
  21. offload/
  22. openmp/
  23. polly/
  24. pstl/
  25. runtimes/
  26. third-party/
  27. utils/
  28. .clang-format
  29. .clang-tidy
  30. .git-blame-ignore-revs
  31. .gitattributes
  32. .gitignore
  33. .mailmap
  34. CODE_OF_CONDUCT.md
  35. CONTRIBUTING.md
  36. LICENSE.TXT
  37. pyproject.toml
  38. README.md
  39. SECURITY.md
README.md

The LLVM Compiler Infrastructure

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Welcome to the LLVM project!

This repository contains the source code for LLVM, a toolkit for the construction of highly optimized compilers, optimizers, and run-time environments.

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