[JakeStevens]

Summary:

Add examples/audio/export_hf_whisper.py to export WhisperForConditionalGeneration directly through Transformers into one .ptn with three methods: encoder maps mel features to hidden states, cross_kv projects per-layer cross-attention keys then values, and decoder consumes token IDs, explicit cache positions, and those projections to produce logits. Self-attention uses zero-initialized mutable static-cache buffers. Positions and the causal mask derive from cache_position, so the runner needs no attention-mask input.

--dump_dir writes runner inputs and an eager greedy transcript with a fresh decoder, preserving the exported cache buffers. An unspecified forced language token is resolved from the example features through Transformers language detection, retaining subsequent forced-token positions. Sparse forced prefixes are rejected. Generation is capped at max_target_positions and skips the unused decoder call after the last requested token.

The export format is independent of the runtime engine. The exporter and the existing LLM example share lowering reports through examples/hf_llm/hf_utils.py. Tests validate native delegation, zero-initialized decoder caches, three-method packaging, and eager numerics. Runtime execution support and runner integration follow in later diffs.

Random-weight loading uses checkpoint generation settings when present, warns when the file is absent, and propagates malformed-config errors. Vector generation supports an unset EOS token by using an empty stop set.

Authored with assistance from Codex.

Reviewed By: digantdesai

Differential Revision: D125295057

[pytorch-bot]

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❌ 1 New Failure, 6 Cancelled Jobs, 1 Unrelated Failure

As of commit 1ac7b5a with merge base 4e439f6 ():

NEW FAILURE - The following job has failed:

• Test ARM Backend / test-arm-vgf / test-backend-linux (arm_vgf_fp, models) / linux-job (gh)
  RuntimeError: Command bash /__w/_temp/exec_script failed with exit code 56

CANCELLED JOBS - The following jobs were cancelled. Please retry:

• Build Presets / apple (ios-simulator) / build (gh)
• Build Presets / apple (ios) / build (gh)
• Build Presets / apple (llm) / build (gh)
• Build Presets / apple (macos) / build (gh)
• Build Presets / apple (profiling) / build (gh)
• Build Presets / apple (pybind) / build (gh)

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

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

• pull / nxp-mcuxpresso-test / linux-job (gh) (trunk failure)
  RuntimeError: Command bash /__w/_temp/exec_script failed with exit code 1

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[digantdesai]

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