[MPS] Fix SDPA output shape when value head dim differs#176843
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hvaara wants to merge 1 commit intopytorch:mainfrom
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[MPS] Fix SDPA output shape when value head dim differs#176843hvaara wants to merge 1 commit intopytorch:mainfrom
hvaara wants to merge 1 commit intopytorch:mainfrom
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🔗 Helpful Links🧪 See artifacts and rendered test results at hud.pytorch.org/pr/176843
Note: Links to docs will display an error until the docs builds have been completed. ✅ No FailuresAs of commit cf60249 with merge base 7643509 ( This comment was automatically generated by Dr. CI and updates every 15 minutes. |
malfet
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Mar 9, 2026
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@pytorchbot merge -f "Lint + MPS is green" |
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This fixes MPS SDPA output shape for cases where
value.size(-1) != query.size(-1), so output now follows(..., L, Ev)as expected. I also added guards in Metal kernel paths that assume equal qkv head dims.Added the updated meta shape inference for the
sdpa_general_mpspath which seems to have been left out initially.Added regression coverage in
test/test_transformers.pycovering the shape semantics, and a similar one intest/test_mps.pythat also checks for numerical parity with CPU.Fixes #176767