Arm backend: Generalize fuse_view_copy_transform_pass

[AdrianLundell]

Update the fuse_view_copy_transform_pass to check shapes rather than args to match different ways of expressing the same shape. This change makes some as_strided ops into noops which they were not previously so an additional noops check is added to fix this.

Additionally moves constants in the pass to class level to simplify overriding behavior for inheriting passes.

Note: test names as_strided_copy -> as_strided since the _copy suffix of operator names are removed in name check.

cc @digantdesai @freddan80 @per @zingo @oscarandersson8218 @mansnils @Sebastian-Larsson @robell

[pytorch-bot]

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[AdrianLundell]

@digantdesai Hi, does this look ok to you?

[AdrianLundell]

Bumping this @digantdesai @kimishpatel

[AdrianLundell]

@digantdesai This patch may also help reducing transposes in some cases since it will remove view ops which are blocking permute fusing sometimes.

[Copilot]

Pull request overview

This PR updates Arm backend view/copy fusion to treat “equivalent” reshape specifications as the same shape by comparing inferred shapes (from meta["val"]) instead of the raw shape arguments. It also tightens TOSA partition rejection logic so partitions that would lower to empty graphs due to newly-detected no-ops are not delegated.

Changes:

• Refactors FuseViewCopyTransform to use class-level constants and removes no-op view_copy based on computed output shape.
• Adds a partitioner no-op detector for aten.as_strided_copy (shape/stride/offset identical) to prevent delegating trivial partitions.
• Updates as_strided-related Arm tests to reflect the new no-op behavior and renamed test functions.

Reviewed changes

Copilot reviewed 3 out of 3 changed files in this pull request and generated no comments.

File	Description
backends/transforms/fuse_view_copy.py	Makes view-copy fusion/removal compare actual inferred shapes (meta["val"].shape) and moves op lists to class attributes for override-friendly behavior.
backends/arm/tosa/partitioner.py	Treats “no-op” as_strided_copy as non-compute to avoid delegating partitions that would be optimized away during lowering.
backends/arm/test/ops/test_as_strided_copy.py	Adjusts test cases to avoid delegating a true no-op as_strided_copy and renames test functions accordingly.

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