Reshape: apply the runtime version guard to the legacy OperationBuilder_v8 too

[YangXu1990uiuc]

Follow-up to the graph-API fix already on develop, which gates
CUDNN_ATTR_OPERATION_RESHAPE_MODE on detail::get_backend_version() in
cudnn_frontend/node/reshape.h.

The legacy OperationBuilder_v8 reshape at cudnn_frontend_Operation.h:1808 has the identical
defect and is worse off: reshape_mode defaults to ReshapeMode_t::VIEW_ONLY rather than
NOT_SET (:240), so the existing if (reshape_mode != NOT_SET) guard is always true and every
legacy reshape sends the attribute to whatever runtime is loaded. Against a pre-9.22 library that
returns CUDNN_STATUS_BAD_PARAM and fails the operation.

Same shape of fix, same reasoning about semantics: skipping the attribute on a pre-9.22 runtime
reproduces that runtime's only behaviour, which is view-only. An explicit ReshapeMode_t::LOGICAL
request cannot be honoured there, so it is refused rather than silently downgraded.

It does not show up in an SDPA reproducer — the SDPA nodes use the graph API — which is why it was
missed when the graph-API half was fixed.

Setting attribute 2202 in isolation reproduces the underlying split: BAD_PARAM on 9.13.1 / 9.18.0 /
9.21.0, success on 9.22.0. The graph-API half was verified end to end by driving an SDPA-backward
graph through validate → build_operation_graph → create_execution_plans → check_support with the
frontend headers held constant and only the runtime library swapped; this half has no SDPA path to
exercise, so it is justified by symmetry with that fix rather than by its own A/B.

Found by an independent review of the graph-API patch.

Summary by CodeRabbit

• Bug Fixes
  • Improved reshape operation compatibility across cuDNN runtime versions.
  • Explicit logical reshapes now report unsupported status on older runtimes.
  • View-only reshapes continue to work on older runtimes without unsupported settings.
  • Newer runtimes retain configured reshape-mode behavior.

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📥 Commits

Reviewing files that changed from the base of the PR and between 073ce27 and 7f39568.

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• include/cudnn_frontend_Operation.h

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📝 Walkthrough

Walkthrough

The reshape operation builder now checks the cuDNN runtime version. It rejects explicit logical reshapes before version 9.22, omits the reshape-mode attribute for legacy view-only reshapes, and preserves configured mode handling on newer runtimes.

Changes

Reshape mode compatibility

Layer / File(s)	Summary
Runtime reshape-mode handling include/cudnn_frontend_Operation.h	The builder applies version-specific behavior for logical and view-only reshape modes.

Estimated code review effort: 2 (Simple) | ~10 minutes

Possibly related PRs

• NVIDIA/cudnn-frontend#466: Adds matching runtime guards for reshape-mode handling.

Suggested labels: cat-bug, mod-frontend, orig-nv-eng

Suggested reviewers: anerudhan

🚥 Pre-merge checks | ✅ 5

✅ Passed checks (5 passed)

Check name	Status	Explanation
Title check	✅ Passed	The title clearly identifies the reshape change and the runtime version guard applied to the legacy builder.
Description check	✅ Passed	The description clearly explains the change, problem, rationale, compatibility behavior, and testing context, although it does not use all template headings.
Docstring Coverage	✅ Passed	No functions found in the changed files to evaluate docstring coverage. Skipping docstring coverage check.
Linked Issues check	✅ Passed	Check skipped because no linked issues were found for this pull request.
Out of Scope Changes check	✅ Passed	Check skipped because no linked issues were found for this pull request.

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