Arm backend: Add correction for floor mode

[wwwind]

Correct implementation of div.tensor_mode for 'floor' case to make it numerically stable.

Change-Id: I6e76bab3528c7b05f7710f6a402791c5b682aee3
Signed-off-by: Elena Zhelezina elena.zhelezina@arm.com

cc @digantdesai @freddan80 @per @zingo @oscarandersson8218

[pytorch-bot]

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❗ 1 Active SEVs

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• Driver update on H100 and A100 instances

❌ 1 New Failure, 2 Unrelated Failures

As of commit 5fa4025 with merge base fb87fa6 ():

NEW FAILURE - The following job has failed:

• pull / test-samsung-models-linux / linux-job (gh)
  RuntimeError: Command docker exec -t 6fa4515b4460ba32b4d61bb622f8d954e5775bde8ae200938759e355c83f2420 /exec failed with exit code 1

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

• trunk / test-models-macos-coreml (mobilebert) / macos-job (gh) (detected as infra flaky with no log or failing log classifier)

BROKEN TRUNK - The following job failed but was present on the merge base:

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

• Apple / build-demo-ios / macos-job (gh) (trunk failure)
  RuntimeError: Command bash /Users/runner/work/_temp/exec_script failed with exit code 74

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[digantdesai]

Thanks!

[zingo]

Hi @wwwind this seem to fail for Ethos-U55

FAILED backends/arm/test/ops/test_div_tensor_mode.py::test_div_tensor_mode_u55_INT[mode_floor] - RuntimeError: Corstone simulation failed:
FAILED backends/arm/test/ops/test_div_tensor_mode.py::test_div_tensor_mode_u55_INT[op_floor_div_rank4_large_randn] - RuntimeError: Corstone simulation failed:

[wwwind]

Thank you @zingo I pushed a fix

[zingo]

fails are unrelated