[AMDGPU][Scheduler] Fix inconsistent MI slots after rematerialization revert  (#180646)

This fixes an issue in the scheduler's rematerialization stage wherein
slot indices could end up being inconsistent with respect to MI order
following a scheduling revert coupled with rematerialization rollbacks.

When a region's schedule is reverted, instructions are re-ordered into
the region's original instruction order. Furthermore, non-debug
instructions have their slot moved if necessary to maintain consistency
between MI and slot order. Importantly, the rematerialization stage
marks rematerialized MIs as debug during re-scheduling. When reverting
the schedule of regions that have had some of their MIs rematerialized,
the latter are still marked debug, and therefore maintain their
pre-re-scheduling slot even if it no longer is consistent with MI order.

This fixes the issue by restoring the original state of rematerialized
MIs before reverting region schedules, ensuring they are moved if
necessary. An EXPENSIVE_CHECK is added to check that slot order
makes sense with respect to MI order in re-scheduled regions.

Fixes SWDEV-579187.
3 files changed
tree: a06f74dae75511427b2f5c1e980b9a1abd55c108
  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
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