[PowerPC] Fix an LowerADDSUBO_CARRY error when converting carry bit for usubo_carry (#137809)

In PowerPC, if a borrow occurs during a subtraction, the carry bit is
zero (unset). The carry bit is set if no borrow occurs.

For ISD::USUBO_CARRY, the nodes produce two results: the normal result
of the addition or subtraction, and a boolean value that is 1 if and
only if there is an outgoing carry or borrow.

Therefore, we need to convert a 1 (which indicates a borrow in
ISD::USUBO_CARRY) to 0 to match PowerPC's definition of borrow.
Similarly, we need to convert a 0 (no borrow in ISD::USUBO_CARRY) to 1
for PowerPC.

To perform this conversion, we use XOR 1 instead of XOR
DAG.getAllOnesConstant(DL, CarryOp.getValueType()).

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2 files changed
tree: d1f593ea9ffebc3a22b227ebbf87a6c22322fcfb
  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/
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  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-format-ignore
  30. .clang-tidy
  31. .git-blame-ignore-revs
  32. .gitattributes
  33. .gitignore
  34. .mailmap
  35. CODE_OF_CONDUCT.md
  36. CONTRIBUTING.md
  37. LICENSE.TXT
  38. pyproject.toml
  39. README.md
  40. SECURITY.md
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