voice_audio_multi/tests/unittests/assets/metal_im2col

Original Metal IM2COL outputs

original_metal_sha256.txt was captured on an Apple M4 Pro from the unmodified Metal backend at audio.cpp commit c8365f391307a97bfe133e0872e632fe572ecace, the parent of the tiled-kernel change. The baseline checkout was clean. Its vendored GGML was built in Release mode with the Metal library embedded.

Each record contains:

case_id ne0 ne1 ne2 ne3 output_bytes input_sha256 output_sha256_first output_sha256_reused

The output hashes cover every raw output byte, including F16 rounding and signed zero. They are frozen outputs from the original GPU kernel, not hashes of the scalar reference or the tiled kernel. Hashes keep the six full-size HiFT outputs in the fixture without storing hundreds of megabytes of tensors.

Inputs use an integer-derived pattern with explicit boundary values. On the second execution, the input is negated and uploaded again. The output buffer is poisoned differently before each execution. Every output element is also checked against a separate scalar indexing implementation.

Coverage includes 1D and 2D, F32/F16, time and patch-column tile boundaries, stride, padding, dilation, odd/even kernels through 1024 taps, multiple channels, batches through 257, contiguous views with nonzero offsets, the public ggml_conv_1d_fast_1d_im2col lowering, and production HiFT shapes.

Run

cmake -S . -B build -DENGINE_BUILD_EXTENDED_TESTS=ON -DENGINE_ENABLE_METAL=ON
cmake --build build --target metal_im2col_test
ctest --test-dir build -R '^metal_im2col_test$' --output-on-failure

This test is enabled by ENGINE_BUILD_EXTENDED_TESTS, independently of ENGINE_BUILD_TESTS. Enabling unit tests alone does not build or register it.

build/bin/metal_im2col_test --benchmark additionally reports median compute time over five synchronized executions of each production shape after the two correctness executions. Timing has no pass/fail threshold. The test needs no model weights and returns CTest's skip code 77 when no Metal device is available.

Updating coverage

Capture new expected outputs only against the original revision above. Compile tests/unittests/test_metal_im2col.cpp against that revision's GGML headers and static Metal/base libraries, with METAL_IM2COL_CAPTURE_BASELINE defined and METAL_IM2COL_GOLDEN_PATH defined to a quoted string. Run that baseline-only executable with --capture-baseline <output-file> and review the fixture diff. The capture build validates every element against the scalar reference before writing its hashes. The normal CMake test build does not expose capture mode and never updates fixtures.