Arm backend: Simplify using a16w8 quantizer in tests

[martinlsm]

cc @freddan80 @per @zingo @oscarandersson8218 @digantdesai

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/16689

• 📄 Preview Python docs built from this PR

Note: Links to docs will display an error until the docs builds have been completed.

❌ 1 New Failure

As of commit 894e617 with merge base 7492d0d ():

NEW FAILURE - The following job has failed:

• trunk / test-models-macos-coreml (ic4) / macos-job (gh)
  Library not loaded: @rpath/liblz4.1.dylib

This comment was automatically generated by Dr. CI and updates every 15 minutes.

[martinlsm]

@pytorchbot label ciflow/trunk

[martinlsm]

@pytorchbot label "partner: arm"

[github-actions]

This PR needs a release notes: label

If your change should be included in the release notes (i.e. would users of this library care about this change?), please use a label starting with release notes:. This helps us keep track and include your important work in the next release notes.

To add a label, you can comment to pytorchbot, for example
@pytorchbot label "release notes: none"

For more information, see
https://github.com/pytorch/pytorch/wiki/PyTorch-AutoLabel-Bot#why-categorize-for-release-notes-and-how-does-it-work.

[Copilot]

Pull request overview

This PR simplifies the use of a16w8 (16-bit activations, 8-bit weights) quantization in ARM backend tests by removing redundant helper functions and directly using the pipeline quantizer API.

Changes:

• Removed local get_symmetric_a16w8_*_quantizer helper functions from each test file
• Replaced pipeline.change_args("quantize", ...) calls with direct pipeline.quantizer.set_global(...) calls
• Cleaned up unused imports (TOSAQuantizer, conftest, TosaSpecification, Quantize)
• Updated copyright years to 2024-2026

Reviewed changes

Copilot reviewed 5 out of 5 changed files in this pull request and generated no comments.

Show a summary per file

File	Description
backends/arm/test/ops/test_view.py	Removed get_symmetric_a16w8_view_quantizer helper, replaced with direct pipeline.quantizer.set_global() calls in 16a8w tests
backends/arm/test/ops/test_slice.py	Removed get_symmetric_a16w8_slice_quantizer helper, replaced with direct pipeline.quantizer.set_global() calls in 16a8w tests
backends/arm/test/ops/test_sigmoid.py	Removed get_symmetric_a16w8_sigmoid_quantizer helper, replaced with direct pipeline.quantizer.set_global() calls preserving epsilon=2**-16
backends/arm/test/ops/test_permute.py	Removed get_symmetric_a16w8_permute_quantizer helper, replaced with direct pipeline.quantizer.set_global() calls in 16a8w tests
backends/arm/test/ops/test_addmm.py	Removed get_symmetric_a16w8_addmm_quantizer helper, replaced with direct pipeline.quantizer.set_global() calls in 16a8w tests

---

💡 Add Copilot custom instructions for smarter, more guided reviews. Learn how to get started.

[zingo]

OK to merge if/when all Arm tests pass