onnx-mlir/README.md

# ONNX MLIR
The Open Neural Network Exchange implementation in MLIR (http://onnx.ai/onnx-mlir/).

| System      | Build Status |
|-------------|--------------|
| x86-Linux   | [![CircleCI](https://circleci.com/gh/onnx/onnx-mlir/tree/master.svg?style=svg)](https://circleci.com/gh/onnx/onnx-mlir/tree/master)             |
| s390-Linux  | [![Build Status](https://yktpandb.watson.ibm.com/jenkins/buildStatus/icon?job=ONNX-MLIR-Linux-s390x-Build)](https://yktpandb.watson.ibm.com/jenkins/job/ONNX-MLIR-Linux-s390x-Build/)             |
| x86-Windows | [![Build Status](https://dev.azure.com/onnx-pipelines/onnx/_apis/build/status/MLIR-Windows-CI?branchName=master)](https://dev.azure.com/onnx-pipelines/onnx/_build/latest?definitionId=9&branchName=master)             |

## Prebuilt Container
An easy way to get started with ONNX-MLIR is to use a prebuilt docker image. These images are created as a result of a successful merge build on the trunk.
This means that the latest image represents the tip of the trunk.
Currently there are images for amd64, ppc64le and IBM System Z respectively saved in Docker Hub as onnxmlirczar/onnx-mlir-build:amd64,
onnxmlirczar/onnx-mlir-build:ppc64le and onnxmlirczar/onnx-mlir-build:s390x. To use one of these images either pull it directly from Docker Hub,
launch a container and run an interactive bash shell in it, or use it as the base image in a dockerfile. The container contains the full build tree including
the prerequisites and a clone of the source code. The source can be modified and onnx-mlir rebuilt from within the container, so it is possible to use it
as a development environment. It is also possible to attach vscode to the running container. An example Dockerfile and vscode configuration files can be
seen in the docs folder. The Dockerfile is shown here.

[same-as-file]: <> (docs/docker-example/Dockerfile)
```
FROM onnxmlirczar/onnx-mlir-build:x86

WORKDIR /build
ENV HOME=/build
ENV PYENV_ROOT=$HOME/.pyenv
ENV PATH=$PYENV_ROOT/shims:$PYENV_ROOT/bin:$PATH
RUN pyenv global 3.7.0
RUN pyenv rehash

ENV PATH=$PATH:/build/bin
RUN apt-get update
RUN apt-get install -y python-numpy
RUN apt-get install -y python3-pip
RUN apt-get install -y gdb
RUN apt-get install -y lldb
RUN apt-get install -y emacs
WORKDIR /build/.vscode
ADD .vscode /build/.vscode
WORKDIR /build

```

## Prerequisites

```
gcc >= 6.4
libprotoc >= 3.11.0
cmake >= 3.15.4
```
At any point in time, ONNX MLIR depends on a specific commit of the LLVM project that has been shown to work with the project. Periodically the maintainers
need to move to a more recent LLVM level. Among other things, this requires that the commit string in utils/clone-mlir.sh be updated. A consequence of
making this change is that the TravisCI build will fail until the Docker images that contain the prereqs are rebuilt. There is a GitHub workflow that rebuilds
this image for the amd64 architecture, but currently the ppc64le and s390x images must be rebuilt manually. The Dockerfiles to accomplish that are in the repo.

## Installation on UNIX

#### MLIR
Firstly, install MLIR (as a part of LLVM-Project):

[same-as-file]: <> (utils/clone-mlir.sh)
``` bash
git clone https://github.com/llvm/llvm-project.git
# Check out a specific branch that is known to work with ONNX MLIR.
cd llvm-project && git checkout 1d01fc100bb5bef5f5eaf92520b2e52f64ee1d6e && cd ..
```

[same-as-file]: <> (utils/build-mlir.sh)
``` bash
mkdir llvm-project/build
cd llvm-project/build
cmake -G Ninja ../llvm \
   -DLLVM_ENABLE_PROJECTS=mlir \
   -DLLVM_BUILD_EXAMPLES=ON \
   -DLLVM_TARGETS_TO_BUILD="host" \
   -DCMAKE_BUILD_TYPE=Release \
   -DLLVM_ENABLE_ASSERTIONS=ON \
   -DLLVM_ENABLE_RTTI=ON

cmake --build . --target -- ${MAKEFLAGS}
cmake --build . --target check-mlir
```

#### ONNX-MLIR (this project)
Two environment variables need to be set:
- LLVM_PROJ_SRC should point to the llvm-project src directory (e.g., llvm-project/).
- LLVM_PROJ_BUILD should point to the llvm-project build directory (e.g., llvm-project/build).

To build ONNX-MLIR, use the following command:

[same-as-file]: <> ({"ref": "utils/install-onnx-mlir.sh", "skip-doc": 2})
```bash
git clone --recursive https://github.com/onnx/onnx-mlir.git

# Export environment variables pointing to LLVM-Projects.
export LLVM_PROJ_SRC=$(pwd)/llvm-project/
export LLVM_PROJ_BUILD=$(pwd)/llvm-project/build

mkdir onnx-mlir/build && cd onnx-mlir/build
cmake ..
cmake --build .

# Run FileCheck tests:
export LIT_OPTS=-v
cmake --build . --target check-onnx-lit
```

After the above commands succeed, an `onnx-mlir` executable should appear in the `bin` directory. 

## Installation on Windows
Building onnx-mlir on Windows requires building some additional prerequisites that are not available by default.

Note that the instructions in this file assume you are using [Visual Studio  2019 Community Edition](https://visualstudio.microsoft.com/downloads/). It is recommended that you have the **Desktop development with C++** and **Linux development with C++** workloads installed. This ensures you have all toolchains and libraries needed to compile this project and its dependencies on Windows.

Run all the commands from a shell started from **"Developer Command Prompt for VS 2019"**.

#### Protobuf
Build protobuf as a static library.

```shell
set root_dir=%cd%
git clone --recurse-submodules https://github.com/protocolbuffers/protobuf.git
cd protobuf
cd cmake
cmake -G "Visual Studio 16 2019" -A x64 -T host=x64 -DCMAKE_BUILD_TYPE=Release -Dprotobuf_MSVC_STATIC_RUNTIME=OFF -Dprotobuf_BUILD_TESTS=OFF -Dprotobuf_BUILD_EXAMPLES=OFF -Dprotobuf_WITH_ZLIB=OFF -DCMAKE_INSTALL_PREFIX="%root_dir%\protobuf\install"
call msbuild protobuf.sln /m /p:Configuration=Release
call msbuild INSTALL.vcxproj /p:Configuration=Release
```

Before running CMake for onnx-mlir, ensure that the bin directory to this protobuf is before any others in your PATH:
```shell
set PATH=%root_dir%\protobuf\install\bin;%PATH%
```

#### PDCurses
Build a local version of the curses library, used by various commandline tools in onnx-mlir. These instructions assume you use [Public Domain Curses](https://pdcurses.org/).

Run this from a Visual Studio developer command prompt since you will need access to the appropriate version of Visual Studio's nmake tool.

```shell
set root_dir=%cd%
git clone https://github.com/wmcbrine/PDCurses.git
set PDCURSES_SRCDIR=%root_dir%/PDCurses
cd PDCurses
call nmake -f wincon/Makefile.vc
```

#### MLIR
Install MLIR (as a part of LLVM-Project):

[same-as-file]: <> (utils/clone-mlir.sh)
```shell
git clone https://github.com/llvm/llvm-project.git
# Check out a specific branch that is known to work with ONNX MLIR.
cd llvm-project && git checkout 1d01fc100bb5bef5f5eaf92520b2e52f64ee1d6e && cd ..
```

[same-as-file]: <> (utils/build-mlir.cmd)
```shell
set root_dir=%cd%
md llvm-project\build
cd llvm-project\build
call cmake -G "Visual Studio 16 2019" -A x64 -T host=x64 ..\llvm ^
   -DCMAKE_INSTALL_PREFIX="%root_dir%\llvm-project\build\install" ^
   -DLLVM_ENABLE_PROJECTS=mlir ^
   -DLLVM_BUILD_EXAMPLES=ON ^
   -DLLVM_TARGETS_TO_BUILD="host" ^
   -DCMAKE_BUILD_TYPE=Release ^
   -DLLVM_ENABLE_ASSERTIONS=ON ^
   -DLLVM_ENABLE_RTTI=ON ^
   -DLLVM_ENABLE_ZLIB=OFF

call cmake --build . --config Release --target -- /m
call cmake --build . --config Release --target install
call cmake --build . --config Release --target check-mlir
```

#### ONNX-MLIR (this project)
The following environment variables need to be set before building onnx-mlir:
- CURSES_LIB_PATH: Path to curses library (e.g. c:/repos/PDCurses)
- LLVM_PROJ_BUILD: Path to the build directory for LLVM (e.g. c:/repos/llvm-project/build)
- LLVM_PROJ_SRC: Path to the source directory for LLVM (e.g. c:/repos/llvm-project)

This project uses lit ([LLVM's Integrated Tester](http://llvm.org/docs/CommandGuide/lit.html)) for unit tests. When running CMake, we will also specify the path to the lit tool from LLVM using the LLVM_EXTERNAL_LIT define.

To build ONNX MLIR, use the following command:

[same-as-file]: <> ({"ref": "utils/install-onnx-mlir.cmd", "skip-doc": 2})
```shell
git clone --recursive https://github.com/onnx/onnx-mlir.git

REM Export environment variables pointing to LLVM-Projects.
set root_dir=%cd%
set CURSES_LIB_PATH=%root_dir%/PDCurses
set LLVM_PROJ_BUILD=%root_dir%/llvm-project/build
set LLVM_PROJ_SRC=%root_dir%/llvm-project

md onnx-mlir\build
cd onnx-mlir\build
call cmake -G "Visual Studio 16 2019" -A x64 -T host=x64 -DLLVM_EXTERNAL_LIT="%root_dir%\llvm-project\build\Release\bin\llvm-lit.py" -DCMAKE_BUILD_TYPE=Release ..
call cmake --build . --config Release --target onnx-mlir -- /m

REM Run FileCheck tests
set LIT_OPTS=-v
call cmake --build . --config Release --target check-onnx-lit
```

After the above commands succeed, an `onnx-mlir` executable should appear in the `bin` directory. 

## Using ONNX-MLIR

The usage of `onnx-mlir` is as such:
```
OVERVIEW: ONNX MLIR modular optimizer driver

USAGE: onnx-mlir [options] <input file>

OPTIONS:

Generic Options:

  --help        - Display available options (--help-hidden for more)
  --help-list   - Display list of available options (--help-list-hidden for more)
  --version     - Display the version of this program

ONNX MLIR Options:
These are frontend options.

  Choose target to emit:
      --EmitONNXIR - Ingest ONNX and emit corresponding ONNX dialect.
      --EmitMLIR   - Lower model to MLIR built-in transformation dialect.
      --EmitLLVMIR - Lower model to LLVM IR (LLVM dialect).
      --EmitLLVMBC - Lower model to LLVM IR and emit (to file) LLVM bitcode for model.
```

## Example

For example, to lower an ONNX model (e.g., add.onnx) to ONNX dialect, use the following command:
```shell
./onnx-mlir --EmitONNXIR add.onnx
```
The output should look like:
```mlir
module {
  func @main_graph(%arg0: tensor<10x10x10xf32>, %arg1: tensor<10x10x10xf32>) -> tensor<10x10x10xf32> {
    %0 = "onnx.Add"(%arg0, %arg1) : (tensor<10x10x10xf32>, tensor<10x10x10xf32>) -> tensor<10x10x10xf32>
    return %0 : tensor<10x10x10xf32>
  }
}
```

## Troubleshooting

If the latest LLVM project fails to work due to the latest changes to the MLIR subproject please consider using a slightly older version of LLVM. One such version, which we use, can be found [here](https://github.com/clang-ykt/llvm-project).