Files
Łukasz Plewa dd824164c8 [offload] Add olMemPrefetch to liboffload (#206752)
Adds olMemPrefetch and the OL_MEM_MIGRATION_FLAG_* enum, wired through a
new dataPrefetchImpl on the plugin interface with Level Zero and CUDA
implementations. Backends without prefetch support inherit the default
no-op.

Prefetch is a hint that migrates a USM allocation between the host and a
device so subsequent accesses on the target side are faster.

Assisted-by: Claude
2026-07-09 18:08:54 +02:00
..
…

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:

$ ./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.

$ OFFLOAD_TRACE=1 ./offload.unittests
---> olInit(nullptr)-> 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 for implementation details.