Eliminate redundant NCHW↔NHWC permute_copy and NHWC-safe view_copy transposes in ToTosaMemoryFormatPass (#18167)

[3l1]

Summary:

Two optimizations in ToTosaMemoryFormatPass to reduce TOSA TRANSPOSE nodes:

1. NHWC-safe reshape detection: When a 4D→4D view_copy has monotonic
   shape_indices on the raw shapes and preserves the last dimension (NHWC
   channel), skip inserting input/output transposes. The view_copy can
   operate directly on NHWC data.

2. Redundant permute_copy elimination: Model-level permute_copy ops whose
   permutation matches channels_last_order (NCHW→NHWC) or its inverse
   (NHWC→NCHW) are redundant with the tosa_dim_order annotation that
   already handles format conversion. Replace them with view_copy (identity
   reshape) to avoid generating TOSA TRANSPOSE nodes. Handles both 4D
   (rank>=4, sr>=2) and 3D (rank>=3, sr>=1) permutations.

Reviewed By: digantdesai

Differential Revision: D96432610

[pytorch-bot]

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❌ 10 New Failures, 1 Unrelated Failure

As of commit 41e5640 with merge base 1e17e28 ():

NEW FAILURES - The following jobs have failed:

• pull / android / run-emulator (gh)
  The process '/usr/local/lib/android/sdk/platform-tools/adb' failed with exit code 224
• pull / unittest-arm-backend-with-no-deps (test_pytest_models_tosa) / linux-job (gh)
  RuntimeError: Command docker exec -t 3ce979773a2fc178d8917e5ad073b13bea29d1ffa73b0445bd70b990a76f7f2b /exec failed with exit code 1
• pull / unittest-arm-backend-with-no-deps (test_pytest_ops_tosa) / linux-job (gh)
  RuntimeError: Command docker exec -t 6ed3efd951779abee7b1fe6629542a74edb37c586158ad7a129f03234c28901e /exec failed with exit code 1
• trunk / test-arm-backend-ethos-u (test_pytest_models_ethos_u55) / linux-job (gh)
  RuntimeError: Command docker exec -t dfdbe3841cec04199797a25ca8908120373155c4869534a4a14d79da3590606d /exec failed with exit code 1
• trunk / test-arm-backend-ethos-u (test_pytest_models_ethos_u85) / linux-job (gh)
  RuntimeError: Command docker exec -t 2c5df06455578f399fc591c8e9b6f7f99ff08f2757ba506d15be54ad6a1e060a /exec failed with exit code 1
• trunk / test-arm-backend-ethos-u (test_pytest_ops_ethos_u55) / linux-job (gh)
  RuntimeError: Command docker exec -t 1597321b6a1e36cc375be63c7d60c368c69da53e6134ac2ce82b28cdc3ae5ecf /exec failed with exit code 1
• trunk / test-arm-backend-ethos-u (test_pytest_ops_ethos_u85) / linux-job (gh)
  RuntimeError: Command docker exec -t 2bf73fa0a50eb4691947b567ecc5918ae5a300233db2d559b47b739b8f594cce /exec failed with exit code 1
• trunk / test-arm-backend-ethos-u (test_smaller_stories_llama) / linux-job (gh)
  RuntimeError: Command docker exec -t 188a98d303ad5ee7f26274f9c4cc5ffb97a653f441563d9ff561cbc876a4fa27 /exec failed with exit code 1
• trunk / test-arm-backend-vkml (test_pytest_ops_vkml) / linux-job (gh)
  RuntimeError: Command docker exec -t b75fa8676590634a0f375f82ea2b3d5b744602df59bd79937a97c36d1a6f605f /exec failed with exit code 1
• trunk / test-arm-ootb-linux (run_deit_e2e_ethos_u) / linux-job (gh)
  AttributeError: 'TosaArg' object has no attribute 'name'

FLAKY - The following job failed but was likely due to flakiness present on trunk:

• pull / unittest-editable / macos / macos-job (gh) (detected as infra flaky with no log or failing log classifier)

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