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llvm / llvm-project / 501c77da6024959438c92f33bd997fe6f39e6b6c
commit501c77da6024959438c92f33bd997fe6f39e6b6c[log] [tgz]
authorVictor Campos <victor.campos@arm.com>Mon Feb 17 10:10:35 2025 +0000
committerGitHub <noreply@github.com>Mon Feb 17 10:10:35 2025 +0000
tree19c887aa6f2b981f9572e41f00d1dda357f9f891
parentc1a229252617ed58f943bf3f4698bd8204ee0f04 [diff]
[LLD][ELF][ARM] Fix resolution of R_ARM_THM_JUMP8 and R_ARM_THM_JUMP11 for big endian (#126933)

These relocations apply to 16-bit Thumb instructions, so reading 16 bits
rather than 32 bits ensures the correct bits are masked and written
back. This fixes the incorrect masking and aligns the relocation logic
with the instruction encoding.

Before this patch, 32 bits were read from the ELF object. This did not
align with the instruction size of 16 bits, but the masking incidentally
made it all work nonetheless. However, this was the case only in little
endian.

In big endian mode, the read 32-bit word had to have its bytes reversed.
With this byte reordering, the masking would be applied to the wrong
bits, hence causing the incorrect encoding to be produced as a result of
the relocation resolution.

The added test checks the result for both little and big endian modes.
2 files changed
tree: 19c887aa6f2b981f9572e41f00d1dda357f9f891
  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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