[lld-macho][test] Make reloc-subtractor.s robust

The test requires that LLVM integreated assembler generates
SUBTRACTOR/UNSIGNED relocations for `.long _minuend_1 - _subtrahend_1`.
This currently works by luck because:

* `_minuend_1` and `_subtrahend_1` are in different fragments (separated by a MCFillFragment)
* and the result is known to be negative at parsing time.

D153096 will change the assembler to fold `.long _minuend_1 - _subtrahend_1` to
a constant, giving ld -order_file no chance to change the result.

To fix the test, move the referenced labels after the label differences to block
constant folding.

Note: you may think the model is somewhat broken and it is. The
.subsections_via_symbols mechanism does not block such constant folding. In
reality SUBTRACTOR/UNSIGNED is for references to another section, which does not
have the problem.

Reviewed By: #lld-macho, smeenai

Differential Revision: https://reviews.llvm.org/D153382
1 file changed
tree: b7b446c21338c0e6f6322e077904f4b86bad0071
  1. .github/
  2. bolt/
  3. clang/
  4. clang-tools-extra/
  5. cmake/
  6. compiler-rt/
  7. cross-project-tests/
  8. flang/
  9. libc/
  10. libclc/
  11. libcxx/
  12. libcxxabi/
  13. libunwind/
  14. lld/
  15. lldb/
  16. llvm/
  17. llvm-libgcc/
  18. mlir/
  19. openmp/
  20. polly/
  21. pstl/
  22. runtimes/
  23. third-party/
  24. utils/
  25. .arcconfig
  26. .arclint
  27. .clang-format
  28. .clang-tidy
  29. .git-blame-ignore-revs
  30. .gitignore
  31. .mailmap
  32. CONTRIBUTING.md
  33. LICENSE.TXT
  34. README.md
  35. SECURITY.md
README.md

The LLVM Compiler Infrastructure

Welcome to the LLVM project!

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