[Backend Tester] Add test flows for QNN

[GregoryComer]

Add test flows for each of the supported QNN quantization modes. I followed the guidance in the docs and example code for the overall lowering flow. Add jobs to nightly CI.

[GregoryComer]

Stack from ghstack (oldest at bottom):

• [Backend Tester] Add markdown summary in CI #13535
• [Backend Tester] Add additional quantized test flows for XNNPACK and Vulkan #13534
• -> [Backend Tester] Add test flows for QNN #13469
• Link QNN backend to pybinding lib when built #13467

[pytorch-bot]

🔗 Helpful Links

🧪 See artifacts and rendered test results at hud.pytorch.org/pr/pytorch/executorch/13469

• 📄 Preview Python docs built from this PR

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

❌ 7 New Failures, 1 Cancelled Job, 2 Unrelated Failures

As of commit e345809 with merge base 0856f59 ():

NEW FAILURES - The following jobs have failed:

• Build documentation / build (buck2) / Build doc (gh)
  At least one of the pre-conditions you specified did not hold
• Lint / lintrunner / linux-job (gh)
  >>> Lint for backends/qualcomm/tests/tester.py:
• trunk / test-huggingface-transformers-coreml (phi4-mini|xnnpack|--quantize) / macos-job (gh)
  RuntimeError: Command bash /Users/runner/work/_temp/exec_script failed with exit code 139
• trunk / test-models-arm-zephyr (add) / linux-job (gh)
  RuntimeError: Command docker exec -t 5617a6227f59e4a3af9a035cb86d880fa65049eac80cf94c52565127a38bfcff /exec failed with exit code 1
• trunk / test-models-arm-zephyr (mv2) / linux-job (gh)
  RuntimeError: Command docker exec -t f55fd29f6d8dac4304908d3736741f4252733014f2901512c4dd63f0eead74f9 /exec failed with exit code 1
• trunk / test-models-arm-zephyr (softmax) / linux-job (gh)
  RuntimeError: Command docker exec -t e9616c3c023cc2122aee709e500c3236765b1cc026563f5344e82074d725c87d /exec failed with exit code 1
• trunk / test-selective-build-macos (cmake) / macos-job (gh)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 134

CANCELLED JOB - The following job was cancelled. Please retry:

• trunk / test-huggingface-transformers-coreml (qwen3-1.7b|xnnpack|--quantize) / macos-job (gh)
  ##[error]The operation was canceled.

BROKEN TRUNK - The following jobs failed but were present on the merge base:

👉 Rebase onto the `viable/strict` branch to avoid these failures

• trunk / test-huggingface-transformers-coreml (olmo-1b|coreml_fp32_gpu|--quantize) / macos-job (gh) (trunk failure)
  RuntimeError: Command bash /Users/runner/work/_temp/exec_script failed with exit code 1
• trunk / test-huggingface-transformers-coreml (smollm2-135m|xnnpack|--quantize) / macos-job (gh) (trunk failure)
  RuntimeError: Command bash /Users/runner/work/_temp/exec_script failed with exit code 138

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

[digantdesai]

why not also add more for xnnpack? Just curious

[cccclai]

Can we rename to qnn_* to align with the naming convention

[GregoryComer]

Sure, I'll update it.

[GregoryComer]

why not also add more for xnnpack? Just curious

Added a few more PT2E flows in the stack. I'll add int4 as well.

[GregoryComer]

Can we rename to qnn_* to align with the naming convention

Done.