Arm backend: Add tools for finding pte info

[Erik-Lundell]

• Add devtools/pte_tool/pte_info.py for getting all compile specs from a pte
• Add backends/arm/scripts/ethosu_pte_info.py for Ethos-U specific info.
• Use ethosu_pte_info.py in build_executor_runner to set default parameters.

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

[pytorch-bot]

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❌ 13 New Failures, 3 Unrelated Failures

As of commit 1d48089 with merge base 2eaa16c ():

NEW FAILURES - The following jobs have failed:

• Apple / build-benchmark-app / macos-job (gh)
  RuntimeError: Command bash /Users/runner/work/_temp/exec_script failed with exit code 1
• Apple / build-frameworks-ios / macos-job (gh)
  RuntimeError: Command bash /Users/runner/work/_temp/exec_script failed with exit code 1
• pull / unittest / linux / linux-job (gh)
  export/tests/test_target_recipes.py::TestTargetRecipes::test_mv2_model
• pull / unittest / macos / macos-job (gh)
  export/tests/test_target_recipes.py::TestTargetRecipes::test_mv2_model
• pull / unittest-editable / linux / linux-job (gh)
  export/tests/test_target_recipes.py::TestTargetRecipes::test_mv2_model
• pull / unittest-editable / macos / macos-job (gh)
  RuntimeError: Command bash /Users/ec2-user/runner/_work/_temp/exec_script failed with exit code 1
• pull / unittest-nxp-neutron / linux-job (gh)
  RuntimeError: Command docker exec -t d4d9fc46572fd4420caebf39fc88103cdf8a714046c6b1013f919f91aeaafcc2 /exec failed with exit code 1
• trunk / test-coreml-delegate / macos-job (gh)
  RuntimeError: Command bash /Users/runner/work/_temp/exec_script failed with exit code 1
• trunk / test-torchao-huggingface-checkpoints (lfm2_5_1_2b, linux.arm64.2xlarge, executorch-ubuntu-22.04-g... / linux-job (gh)
  RuntimeError: Command docker exec -t 43d9788a9033cdce0472fbeb59c4e8e24d2b86d694693c0cc473513a45fd796b /exec failed with exit code 1
• trunk / test-torchao-huggingface-checkpoints (phi_4_mini, linux.arm64.2xlarge, executorch-ubuntu-22.04-gc... / linux-job (gh)
  RuntimeError: Command docker exec -t 9905b8907080b3d6caabe2fed43a212362d32cba40b23c56eb7426c3cdc7958c /exec failed with exit code 1
• trunk / test-torchao-huggingface-checkpoints (qwen3_4b, linux.arm64.2xlarge, executorch-ubuntu-22.04-gcc1... / linux-job (gh)
  RuntimeError: Command docker exec -t 25aa77eff7b28a473b10cb666b6cf26cf4ed3a3507e448ff480ec7e185cfda39 /exec failed with exit code 1
• trunk / unittest-release / linux / linux-job (gh)
  export/tests/test_target_recipes.py::TestTargetRecipes::test_mv2_model
• trunk / unittest-release / macos / macos-job (gh)
  export/tests/test_target_recipes.py::TestTargetRecipes::test_mv2_model

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

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

• pull / unittest / windows / windows-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• pull / unittest-editable / windows / windows-job (gh) (trunk failure)
  ##[error]The operation was canceled.
• trunk / unittest-release / windows / windows-job (gh) (trunk failure)
  ##[error]The operation was canceled.

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

[digantdesai]

Bunch of good discussion on this topic - #7088

[digantdesai]

I think the original idea was if we have these tools in C++, since we will likely be in Python-free environment, it might be handly. In my mind the analogy is with https://www.gnu.org/software/binutils.

[Erik-Lundell]

I think the original idea was if we have these tools in C++, since we will likely be in Python-free environment, it might be handly. In my mind the analogy is with https://www.gnu.org/software/binutils.

Interesting. I would have expected a user to use tools like these as a part of their aot-flow (generate -> inspect -> re-generate), or when cross-compiling on host. What python-free environment do you have in mind?

The way I am reading the discussion, a general pteinspect with subcommands would be preferable, correct? Something like pteinspect list-compile-specs?

(On a side note, this was done as quick un-planned work. If lots of changes are needed, I'll close the PR and postpone this until we have a proper ask for it 😁)