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llvm / llvm-project / 552c0d14d13df8d05fc970425b806bc7e2ca9c8c
commit552c0d14d13df8d05fc970425b806bc7e2ca9c8c[log] [tgz]
authorPhilip Reames <preames@rivosinc.com>Thu Aug 28 10:49:46 2025 -0700
committerGitHub <noreply@github.com>Thu Aug 28 10:49:46 2025 -0700
tree16fea34ed41c495f6a91b186eb1bcb7a11d0dd4e
parentd254aed8dbdd73bc18c018a97009de3c40756ed3 [diff]
[RISCV] Use XORI/SLLI/ADDI to when materializing select of constants (#155845)

This case is the inverse of the one introduced in #155644. The
complexity with the inversion is that we need to also invert the
condition before shifting it. I had originally planned to only do so
when the condition was "cheaply" invertible (i.e. didn't require the
xori), but when looking more closely at the diffs I noticed that while
the XORI prevents this from being an icount improvement, and actually
lengthens slightly the critical path, it does still reduce the number of
registers needed.
3 files changed
tree: 16fea34ed41c495f6a91b186eb1bcb7a11d0dd4e
  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
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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