torch-mlir/include/npcomp/Backend/IREE/README.md

# IREE Backend

Passes/utilities for preparing input to IREE.

For now, this directory doesn't have a C++-level dependency on IREE, since
it only performs a trivial transformation. Eventually, if lowering
nontrivial constructs to IREE (such as a list type to `!iree.list`),
we will need to take that dependency, and it will be isolated to this directory.
Add support for compiling through IREE. Recommended review order: - Changes in frontends/pytorch/examples/ - Changes in python/npcomp/compiler/pytorch/backend/ - Boilerplate for the `npcomp-iree-backend-lower-linkage` pass. This change separates out a `npcomp.compiler.pytorch.backend.frontend_lowering` module that does the common lowering for all backends. The individual compiler backends `npcomp.compiler.pytorch.backend.{refjit,iree}` now accept a loosely defined "TCP + scalar code" IR mix that will be formalized in the future as the interface to codegen backends. This also required adding a small pass `npcomp-iree-backend-lower-linkage` which adds `iree.module.export` onto functions, and layering that into the frontend flow. The pass doesn't require a C++-level dependency on IREE, which is nice for now. TBD how we are going to handle lists (we hope we can get away with sneakerneting some td files and relying on loose IR compatibility). Running through IREE requires the ability to import `iree.compiler` and `iree.runtime`, which can be obtained as follows: ``` python3 -m pip install iree-compiler-snapshot iree-runtime-snapshot -f https://github.com/google/iree/releases/tag/snapshot-20210406.200 PYTHONPATH="${PYTHONPATH}:${MY_IREE_BUILD}/bindings/python/" ``` This patch makes it painfully clear that we don't have any e2e testing harness to really plug into, and also don't have a usable Python API to our compiler stack (something usable in a jupyter notebook). That will be addressed in subsequent commits. We've been flying by the seat of our pants with this `examples` directory that isn't subject to any kind of testing or real usability concerns. 2021-04-09 04:05:16 +08:00			`# IREE Backend`

			`Passes/utilities for preparing input to IREE.`

			`For now, this directory doesn't have a C++-level dependency on IREE, since`
			`it only performs a trivial transformation. Eventually, if lowering`
			nontrivial constructs to IREE (such as a list type to `!iree.list`),
			`we will need to take that dependency, and it will be isolated to this directory.`