Vulkan GPU HAL Driver

IREE can accelerate model execution on GPUs via Vulkan, a low-overhead graphics and compute API. Vulkan is cross-platform: it is available on many operating systems, including Android, Linux, and Windows. Vulkan is also cross-vendor: it is supported by most GPU vendors, including AMD, ARM, Intel, NVIDIA, and Qualcomm.

Support matrix

As IREE and the compiler ecosystem it operates within matures, more target specific optimizations will be implemented. At this stage, expect reasonable performance across all GPUs and for improvements to be made over time for specific vendors and architectures.

GPU Vendor	Category	Performance	Focus Architecture
ARM Mali GPU	Mobile	Good	Valhall
Qualcomm Adreno GPU	Mobile	Reasonable	640+
AMD GPU	Desktop/server	Reasonable	-
NVIDIA GPU	Desktop/server	Reasonable	-

Prerequisites

In order to use Vulkan to drive the GPU, you need to have a functional Vulkan environment. IREE requires Vulkan 1.1 on Android and 1.2 elsewhere. It can be verified by the following steps:

AndroidLinuxWindows

Android mandates Vulkan 1.1 support since Android 10. You just need to make sure the device's Android version is 10 or higher.

Run the following command in a shell:

vulkaninfo | grep apiVersion

If vulkaninfo does not exist, you will need to install the latest Vulkan SDK. For Ubuntu 18.04/20.04, installing via LunarG's package repository is recommended, as it places Vulkan libraries and tools under system paths so it's easy to discover.

If the showed version is lower than Vulkan 1.2, you will need to update the driver for your GPU.

Run the following command in a shell:

vulkaninfo | grep apiVersion

If vulkaninfo does not exist, you will need to install the latest Vulkan SDK.

If the showed version is lower than Vulkan 1.2, you will need to update the driver for your GPU.

Get runtime and compiler

Get IREE runtime with Vulkan HAL driver

Next you will need to get an IREE runtime that supports the Vulkan HAL driver so it can execute the model on GPU via Vulkan.

Build runtime from source

Please make sure you have followed the Getting started page to build IREE for Linux/Windows and the Android cross-compilation page for Android. The Vulkan HAL driver is compiled in by default on non-Apple platforms.

Ensure that the IREE_HAL_DRIVER_VULKAN CMake option is ON when configuring for the target.

Get compiler for SPIR-V exchange format

Vulkan expects the program running on GPU to be expressed by the SPIR-V binary exchange format, which the model must be compiled into.

Download as Python package

Python packages for various IREE functionalities are regularly published to PyPI. See the Python Bindings page for more details. The core iree-compiler package includes the SPIR-V compiler:

python -m pip install iree-compiler

Tip

iree-compile is installed to your python module installation path. If you pip install with the user mode, it is under ${HOME}/.local/bin, or %APPDATA%Python on Windows. You may want to include the path in your system's PATH environment variable.

export PATH=${HOME}/.local/bin:${PATH}

Build compiler from source

Please make sure you have followed the Getting started page to build IREE for Linux/Windows and the Android cross-compilation page for Android. The SPIR-V compiler backend is compiled in by default on all platforms.

Ensure that the IREE_TARGET_BACKEND_VULKAN_SPIRV CMake option is ON when configuring for the host.

Compile and run the model

With the compiler for SPIR-V and runtime for Vulkan, we can now compile a model and run it on the GPU.

Compile the model

IREE compilers transform a model into its final deployable format in many sequential steps. A model authored with Python in an ML framework should use the corresponding framework's import tool to convert into a format (i.e., MLIR) expected by main IREE compilers first.

Using MobileNet v2 as an example, you can download the SavedModel with trained weights from TensorFlow Hub and convert it using IREE's TensorFlow importer. Then,

Compile using the command-line

Run the following command (passing --iree-input-type= as needed for your import tool):

iree-compile \
    --iree-hal-target-backends=vulkan-spirv \
    --iree-vulkan-target-triple=<...> \
    --iree-input-type=mhlo \
    iree_input.mlir -o mobilenet-vulkan.vmfb

where iree_input.mlir is the imported program.

Note that a target triple of the form <vendor/arch>-<product>-<os> is needed to compile towards each GPU architecture. If no triple is specified then a safe but more limited default will be used. We don't support the full spectrum here¹; the following table summarizes the currently recognized ones:

GPU Vendor	Target Triple
ARM Mali GPU	valhall-g78-android30
Qualcomm Adreno GPU	adreno-unknown-android30
AMD GPU	e.g., rdna1-5700xt-linux
NVIDIA GPU	e..g, ampere-rtx3080-windows
SwiftShader CPU	cpu-swiftshader-unknown

Run the model

Run using the command-line

In the build directory, run the following command:

tools/iree-run-module \
    --device=vulkan \
    --module=mobilenet-vulkan.vmfb \
    --function=predict \
    --input="1x224x224x3xf32=0"

The above assumes the exported function in the model is named as predict and it expects one 224x224 RGB image. We are feeding in an image with all 0 values here for brevity, see iree-run-module --help for the format to specify concrete values.

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1. It's also impossible to capture all details of a Vulkan implementation with a target triple, given the allowed variances on extensions, properties, limits, etc. So the target triple is just an approximation for usage. ↩