offload/liboffload/README.md

# Liboffload

This directory contains the implementation of the work-in-progress new API for
Offload. It builds on top of the existing plugin implementations but provides a
single level of abstraction suitable for implementation of many offloading
language runtimes, rather than just OpenMP.

## Testing liboffload

The main test suite for liboffload can be run with the `check-offload-unit`
target, which runs the `offload.unittests` executable. The test suite will
automatically run on every available device, but can be restricted to a single
platform (CUDA, AMDGPU) with a command line argument:

```sh
$ ./offload.unittests --platform=CUDA
```

Tracing of Offload API calls can be enabled by setting the `OFFLOAD_TRACE`
environment variable. This works with any program that uses liboffload.

```sh
$ OFFLOAD_TRACE=1 ./offload.unittests
---> olInit()-> OL_SUCCESS
# etc
```

The host plugin is not currently supported.

## Modifying liboffload

The main header (`OffloadAPI.h`) and some implementation details are
autogenerated with tablegen. See the [API definition README](API/README.md)
for implementation details.