SYCL MLIR Compiler Internship

SYCL is a C++-based heterogeneous programming standard for accelerator computing.  Codeplay works on implementations of this standard and are investigating using the MLIR compiler framework to enable SYCL-aware optimizations at compile time. This includes allowing the creation of SYCL language extensions so that the programmer can provide more accurate descriptions of their program to enable compiler optimizations. The advantage of MLIR for the implementation of  such extensions is that compiler information for both the "host" code, that runs on the CPU, and the "device" code, that runs on the accelerator, can be considered together more easily allowing for optimizations that would not be possible based on knowledge of either side of the program alone.

One of the extensions supported by the MLIR-based is kernel fusion. If eligible, by using this extension, two or more kernels can be fused into a single one in order to reduce overhead (kernel launch or memory I/O for instance). For fusion to be legal, the compiler must ensure that the resulting visible memory writes are unchanged.  An important part of the performance boost comes from the internalization of some memory buffers: if two kernels communicate with each other via a buffer in global memory, this buffer can be replaced by a piece of private or local memory.  This is an optimization because private and local memory exist closer to the compute device, but are much smaller and is not visible to all work-items. The implementation, however, is currently limited by its inability to understand which region of the memory is accessed so that it can create tiles of data to operate on these smaller, faster memories.

The ideal candidate will be someone who has a strong interest in compilers, who is able to progress on tasks autonomously while sharing progress or blockers with their team.  For reference and for further information on the kernel fusion extension, feel free to visit the kernel fusion extension proposal or the kernel fusion paper published in TACO.

This internship is on offer for a duration of 3-6 months. Although we usually offer internships for the summer, we are delighted to accept applications for longer or shorter internships and many of our interns have stayed with us to do university placement years or have become permanent members of our team.

The position is temporary and will be based at our head office in central Edinburgh. The successful candidate must, by the start of their employment, have successfully obtained the right to work in the UK. 

Starting salary - Competitive & Negotiable

Responsibilities

You will:

• Work as part of a small team of compiler developers investigating options for the future design of SYCL compilers.
• Develop MLIR passes with the help of the team.
• Develop passes to identify regions of memory read and/or write by work items of a SYCL compute kernel.
• Develop passes to identify how memory accesses overlap between two kernels to determine if two kernels can be fused and potentially to which type of memory a buffer can be promoted to.
• Learn about Clang, LLVM, MLIR.
• Learn about heterogeneous programming and language design, particularly for SYCL.

What We Offer

Codeplay is internationally recognized as being at the forefront of software development technology. Working at Codeplay offers unique opportunities and challenges to learn new technologies and to get involved in shaping the software industry. Codeplay's projects range from: creating tools and tool sets (optimizing compilers, debuggers, profilers, programming models & APIs, test systems/suites, etc.) for brand-new unannounced next-generation hardware; developing and optimizing current machine learning (TensorFlow™) and computer vision applications; research and development into lowering the power consumption of mobile devices; and contributing to new programming models and software standards (e.g. C++, SYCL™, OpenCL™, Vulkan® and SPIR™-V).

Codeplay Software is a world pioneer in enabling acceleration technologies used in AI, HPC and automotive. Codeplay was established in 2002 in Edinburgh, Scotland and developed some of the first tools enabling complex software to be accelerated using graphics processors. Today, most AI software is developed using graphics processors designed for video games, and more recently specialised AI and computer vision accelerators. Codeplay continues to work with global technology leaders to make the latest complex AI systems programmable using open-standards based programming languages and allows application developers to quickly bring software to the market.  Codeplay is also deeply involved with the definition of open standards, especially OpenCL™, SPIR™, SYCL™, and Vulkan™ through The Khronos Group, and MISRA C++ for automotive.

• A friendly and relaxed working environment where colleagues respect and support each other.
• Learn from experienced colleagues: our staff frequently give company-wide knowledge-sharing presentations on new software and technology trends, personal projects and other relevant subjects.
• Great career prospects within a growing company
• Newstart mentoring scheme
• Flexible working hours
• Frequent company social events (social nights, pot luck lunches, gaming, karting, outdoor adventures, and more)

Required Skills

The ideal candidate is a self-motivated individual who can work through a problem from start to finish, meet deadlines as required to support software projects, and has the ability to work under pressure. You will be working on technology that is seldom announced to the public and could be several years away from public release, so confidentiality is critical. You should be able to work both independently and collaboratively within teams of varying skill sets and expertise. You should be welcoming towards, and able to adapt to, the introduction of new technologies, responsibilities and projects, as Codeplay works with cutting-edge technology and takes on a diverse range of projects.

• C++ development experience
• Some level of compiler experience, e.g. coursework or research project
• Good written English and communication skills
• Working knowledge of source control and configuration management tools

Beneficial Skills

Knowledge and/or experience of any of the following would be useful for the role, but are not essential. You must be able to learn new skills, but will be given support from Codeplay's team to get you up to speed.

• Knowledge of Clang or LLVM.
• Knowledge of MLIR.
• Knowledge of polyhedral compilation.
• Knowledge of parallel IRs such as SPIR-V or PTX.
• Knowledge of heterogeneous programming, e.g. CUDA, SYCL, OpenCL, etc.
• Knowledge of parallel architectures, such as GPUs.
• Knowledge of build systems (e.g. CMake) and compiler tool-chains.
• Experience working in a team.

Application Guidance

Any application which results in a job offer is conditional upon the candidate already having or successfully applying for the right to work in the UK. Codeplay is proud to be an Equal Opportunities employer. We celebrate and value diversity. We are committed to creating an inclusive environment for all employees, regardless of race, colour, gender, religion, national origin, ancestry, citizenship, disability, age, sexual orientation or any other characteristic protected by law. All employment is decided on the basis of qualifications, merit and business need and we strongly encourage applicants from all backgrounds and walks of life. If you have a disability or additional need that requires accommodation, just let us know.

The Cover Note/Letter is just as important as your CV/Resume, so please include one, stating why you believe you are a good fit for the position. If you have examples of relevant work or projects, we would love to see them, so please include links to them in your application.You should be studying towards a degree in a relevant subject; however, if you can prove skills and knowledge through portfolio work, projects or previous employment, then a degree is not essential.If you have C++ Code Samples (where relevant) please put the link to these on your application; Our system will only accept links to personal projects/GitHub accounts or PDF documents.

We aim to close this advert on the 28th April 2023, so please look to get your application in prior to this date. We anticipate a high level of applications for this role and so reserve the right to close this vacancy prior to the closing date given.