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tigris compile

Compile an ONNX model into a binary .tgrs execution plan for deployment on embedded devices.

Terminal window
tigris compile MODEL [OPTIONS]
Flag Type Required Description
MODEL path yes ONNX model file (.onnx)
-m, --mem size (multiple) yes Memory pools, fast to slow (e.g. -m 256K or -m 256K -m 8M)
-o, --output path no Output .tgrs path (default: MODEL.tgrs)
-f, --flash size no Flash budget. Warns if plan exceeds this size.
-c, --compress none / lz4 no Weight compression (default: none)
--xip flag no Execute-in-place: weights read directly from flash at runtime

The compiler runs a 7-stage pipeline:

  1. Load. Import the ONNX model, fold constants, canonicalize the graph.
  2. Normalize. Fold QDQ patterns, extract quantization parameters, lower ops to TiGrIS op types.
  3. Lifetimes. Compute tensor lifetimes from the execution order.
  4. Memory Timeline. Build the activation memory timeline, compute peak memory.
  5. Temporal Partition. Split the graph into stages that each fit within the SRAM budget, inserting spill/reload ops at stage boundaries.
  6. Spatial Partition. For stages that still exceed the budget, compute spatial tiling plans (tile height, halo, receptive field) and detect chain-tileable stage sequences.
  7. Binary Emit. Serialize to the .tgrs binary format.

The output is a single .tgrs file designed for zero-copy, zero-alloc loading on the target device.

When --xip is enabled on an uncompressed plan, the runtime reads weights directly from flash via memory-mapped I/O instead of copying the full weight blob to RAM. The plan binary format is designed for memory-mapped access, so the C loader returns pointers directly into the mapped buffer. If weight compression is also enabled, weights are still stored compactly in flash but each stage’s compressed block is decompressed into the fast arena before execution.

LZ4 compression reduces plan size on flash at the cost of a small SRAM overhead for decompression at runtime.

Terminal window
tigris compile model.onnx -m 256K -c lz4 -o model.tgrs

When compression is enabled:

  • Weights are compressed per stage into individual blocks
  • At runtime, the executor decompresses one stage’s weights at a time into a reserved prefix of the SRAM arena
  • Size the complete core fast arena with tigris_fast_arena_required(&plan); it includes the simultaneous decompression reservation without duplicating the runtime’s arithmetic
  • The plan reports both compressed and uncompressed sizes

Compile with a 256K SRAM budget:

Terminal window
tigris compile ds_cnn.onnx -m 256K -o ds_cnn.tgrs

Output:

Binary plan written to ds_cnn.tgrs
28 ops, 3 stages @ 256.00 KiB budget
plan size: 87.42 KiB

Compile with LZ4 compression and flash budget check:

Terminal window
tigris compile mobilenetv2.onnx -m 256K -c lz4 -f 4M -o mobilenetv2.tgrs

Output:

Binary plan written to mobilenetv2.tgrs (LZ4 compressed)
53 ops, 12 stages @ 256.00 KiB budget
plan size: 2.85 MiB (uncompressed: 3.41 MiB, ratio: 0.84x)
flash 4.00 MiB: fits

Two-pool memory (SRAM + PSRAM):

Terminal window
tigris compile yolov5n.onnx -m 232K -m 6M -o yolov5n.tgrs