CCGX: Generate C++ bindings from GX code

Installation

1. Install a recent version of Go (see All Releases)
2. Install ccgx using the following command:

   $ GOBIN=<target folder> go install github.com/gx-org/ccgx@latest
   

   (if GOBIN is not specified, the default is ~/go/bin/ccgx)
3. Install gopjrt, the XLA backend used by GX:

   $ export GOPJRT_NOSUDO=true
   $ export GOPJRT_INSTALL_DIR=$HOME/gopjrtbin
   $ export CGO_CFLAGS="-I $GOPJRT_INSTALL_DIR/include"
   $ export LD_LIBRARY_PATH=$GOPJRT_INSTALL_DIR/lib
   $ curl -sSf https://raw.githubusercontent.com/gomlx/gopjrt/main/cmd/install_linux_amd64.sh | bash
   

   Note that GOPJRT_INSTALL_DIR is going to be used later in CMakeLists.txt.

Running helloworld

This example explains how to run the example in ccgx/examples/helloworld.

1. Create the project folder:

   $ mkdir helloworld
   $ cd helloworld
   

2. Create a minimal helloworld.gx file such as:

   package helloworld
   
   import _ "github.com/gx-org/xlapjrt/gx"
   
   // Hello returns a constant array of two axes of size 2 and 3.
   func Hello() [2][3]float32 {
   	return [2][3]float32{
   		{1, 2, 3},
   		{4, 5, 6},
   	}
   }

   Note the import which adds a dependency to the XLA backend. See ccgx/examples/helloworld/helloworld.gx as a reference.
3. Run the following command to create go.mod and go.sum:

   $ ccgx mod init helloworld
   

   These files manage all the dependencies of the project and their versions for reproducable builds. After new dependencies are added or removed in GX source files, run:

   $ ccgx mod tidy 
   

   to update go.mod from the latest imports in the GX source files.
4. Run the following command to generate a corresponding C++ source and header files:

   $ ccgx bind --cmake
   

   The files are generated in the gxdeps folder.
5. Create the C++ file helloworld.cc and its CMakeLists.txt
6. Compile and run the project with cmake:

   $ mkdir build
   $ cd build
   $ cmake ..
   $ make
   $ ./helloworld
   

Disclaimer

This is not an official Google DeepMind product (experimental or otherwise), it is just code that happens to be owned by Google-DeepMind. GX is experimental and work in progress. As of today, we do not consider any part of the language as stable. Breaking changes will happen on a regular basis.

You are welcome to send PR or to report bugs. We will do our best to answer but there is no guarantee that you will get a response.