[unroll-and-jam] Document dependency patterns in dependencies.ll (NFC) #156577
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Add detailed comments explaining each function's memory access patterns and why they should/shouldn't be unroll-and-jammed: - fore_aft_*: Dependencies between fore block and aft block - fore_sub_*: Dependencies between fore block and sub block - sub_aft_*: Dependencies between sub block and aft block - sub_sub_*: Dependencies within sub block - *_less: Backward dependency (i-1) - safe for fore/aft, fore/sub, sub/aft; unsafe for sub/sub due to jamming conflicts - *_eq: Same iteration dependency (i+0) - safe due to preserved execution order - *_more: Forward dependency (i+1) - unsafe due to write-after-write races between unrolled iterations, except sub/sub case creates conflicts
sjoerdmeijer
approved these changes
Oct 2, 2025
Meinersbur
approved these changes
Oct 6, 2025
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Add detailed comments explaining each function's memory access patterns and why they should/shouldn't be unroll-and-jammed:
fore_aft_*: Dependencies between fore block and aft block
fore_sub_*: Dependencies between fore block and sub block
sub_aft_*: Dependencies between sub block and aft block
sub_sub_*: Dependencies within sub block
*_less: Backward dependency (i-1) - safe for fore/aft, fore/sub, sub/aft; unsafe for sub/sub due to jamming conflicts
*_eq: Same iteration dependency (i+0) - safe due to preserved execution order
*_more: Forward dependency (i+1) - unsafe due to write-after-write races between unrolled iterations, except sub/sub case creates conflicts