With the potential of quantum algorithms to solve intractable classical problems, quantum computing is rapidly evolving, and more algorithms are being developed and optimized. Expressing these quantum algorithms using a high-level language and making them executable on a quantum processor while abstracting away hardware details is a challenging task. First, a quantum programming language should provide an intuitive programming interface to describe those algorithms. Then a compiler has to transform the program into a quantum circuit, optimize it, and map it to the target quantum processor respecting the hardware constraints such as the supported quantum operations, the qubit connectivity, and the control electronics limitations. In this article, we propose a quantum programming framework named OpenQL, which includes a high-level quantum programming language and its associated quantum compiler. We present the programming interface of OpenQL, we describe the different layers of the compiler and how we can provide portability over different qubit technologies. Our experiments show that OpenQL allows the execution of the same high-level algorithm on two different qubit technologies, namely superconducting qubits and Si-Spin qubits. Besides the executable code, OpenQL also produces an intermediate quantum assembly code, which is technology independent and can be simulated using the QX simulator.

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Scientific computing is at the core of many High-Performance Computing applications, including computational flow dynamics. Because of the utmost importance to simulate increasingly larger computational models, hardware acceleration is receiving increased attention due to its potential to maximize the performance of scientific computing. Field-Programmable Gate Arrays could accelerate scientific computing because of the possibility to fully customize the memory hierarchy important in irregular applications such as iterative linear solvers. In this article, we study the potential of using Field-Programmable Gate Arrays in High-Performance Computing because of the rapid advances in reconfigurable hardware, such as the increase in on-chip memory size, increasing number of logic cells, and the integration of High-Bandwidth Memories on board. To perform this study, we propose a novel Sparse Matrix-Vector multiplication unit and an ILU0 preconditioner tightly integrated with a BiCGStab solver kernel. We integrate the developed preconditioned iterative solver in Flow from the Open Porous Media project, a state-of-the-art open source reservoir simulator. Finally, we perform a thorough evaluation of the FPGA solver kernel in both stand-alone mode and integrated in the reservoir simulator, using the NORNE field, a real-world case reservoir model using a grid with more than 105 cells and using three unknowns per cell.

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Memristor-based Computation-in-Memory (CIM) is one of the emerging architectures for next-generation Big Data problems. Its design requires a radically new synthesis flow as the memristor is a passive device that uses resistances to encode its logic values. This article proposes a synthesis flow for mapping parallel applications on memristor-based CIM architecture. First, it employs solution templates that contain scheduling, placement, and routing information to map multiple algorithms with similar data flow graphs to the memristor crossbar; this template is named skeleton. Complex algorithms that do not fit a single skeleton can be solved by nested skeletons. Therefore, this approach can be applied to a wide range of applications while using a limited number of skeletons only. Second, it further improves the design when spatial and temporal patterns exist in input data. To accelerate simulation of generated SystemC models, we integrate MPI in skeletons. The synthesis flow and its additional features are verified with multiple applications, and the results are compared against a multicore platform. These experiments demonstrate the feasibility and the potential of this approach.

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Sparse Matrix Vector Multiplication (SpMV) is a key kernel in various domains, that is known to be difficult to parallelize efficiently due to the low spatial locality of data. This is problematic for computing large-scale SpMV due to limited cache sizes but also in achieving speedups through parallel execution. To address these issues, we present 1) sparstition, a novel partitioning scheme that enables computing SpMV without the need to do any major post-processing steps, and 2) a corresponding HLS-based hardware design that is able to perform large-scale SpMV efficiently. The design is pipelined so the matrix size is limited only by the size of the off-chip memory (DRAM) and not by the available on-chip memory (BRAMs). Our experimental results, performed on a ZedBoard, show that we achieve a computational throughput of up to 300 MFLOPS in single-precision and 108 MFLOPS in double-precision, an improvement of 2.6X on average compared to current state-of-the-art HLS results. Finally, we predict that sparstition can boost the computational throughput of HLS-based SpMV kernel to over 10 GFLOPS when using High Bandwidth Memories.

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Computation-in-Memory (CiM) is a new computer architecture template based on the in-memory computing paradigm. CiM can solve the memory-wall problem of classical Von Neumann-based computer systems by exploiting application-specific computational and data-flow patterns with the capability of performing both storage and computations of emerging resistive RAM technologies (e.g., memristors). However, to efficiently explore and design such radically new application-specific CiM architectures, we require fundamentally new algorithm specification and compilation techniques. In this paper, we introduce a domain-specific language to express not only the computational patterns of an algorithm but also its spatial characteristics. Furthermore, we design a compiler that is able to transform these patterns into highly-optimized CiM designs. Experiments demonstrate the functional correctness of the language and the compiler as well as an order of magnitude speedup improvement over a multicore system in both performance and energy costs.@en

Today's computer architectures suffer from many challenges, such as the near end of CMOS downscaling, the memory/communication bottleneck, the power wall, and the programming complexity. As a consequence, these architectures become inefficient in solving big data problems or general data intensive applications. Computation-in-memory (CIM) is a novel architecture that tries to solve/alleviate the impact of these challenges using the same device (i.e., the memristor) to implement the processor and memory in the same physical crossbar. In order to analyze its feasibility in depth, this paper proposes two memristor implementations of a data intensive arithmetic application (i.e., parallel addition). To the best of our knowledge, this is the first paper that considers the cost of the entire architecture including both crossbar and its CMOS controller. The results show that CIM architecture in general and the CIM parallel adder in particular have a high scalability. CIM parallel adder achieves at least two orders of magnitude improvement in energy and area in comparison with a multicore-based parallel adder. Moreover, due to a wide variety of memristor design methods (such as Boolean logic), tradeoffs can be made between the area, delay, and energy consumption.@en

One of the most important constraints of today’s architectures for data-intensive applications is the limited bandwidth due to the memory-processor communication bottleneck. This significantly impacts performance and energy. For instance, the energy consumption share of communication and memory
access may exceed 80%. Recently, the concept of Computation-in-Memory (CIM) was proposed, which is based on the integration of storage and computation in the same physical location using a crossbar topology and non-volatile resistive-switching memristor technology. To illustrate the tremendous potential of CIM architecture in exploiting massively parallel computation while reducing the communication overhead, we present a communicationefficient mapping of a large-scale matrix multiplication algorithm on the CIM architecture. The experimental results show that, depending on the matrix size, CIM architecture exhibits several orders of magnitude higher performance in total execution time
and two orders of magnitude better in total energy consumption than the multicore-based on the shared memory architecture.@en

Memristor-based Computation-in-Memory is one of the emerging architectures proposed to deal with Big Data problems. The design of such architectures requires a radically new automatic design flow because the memristor is a passive device that uses resistance to encode its logic value. This paper proposes a design flow for mapping parallel algorithms on the CIM architecture. Algorithms with similar data flow graphs can be mapped on the crossbar using the same template containing scheduling, placement, and routing information; this template is named skeleton. By configuring such a skeleton with different pre-designed circuits, we can build CIM implementations of the corresponding algorithms in that class. This approach does not only map an algorithm on a memristor crossbar, but also gives an estimation of its performance, area, and energy consumption. It also supports user-defined constraints and parallel SystemC simulation. Experimental results demonstrate the feasibility and the potential of the approach.@en

Numerous applications for mobile devices require 3D vision capabilities, which in turn require depth detection since this enables the evaluation of an object’s distance, position and shape. Despite the increasing popularity of depth
detection algorithms, available solutions need expensive hardware and/or additional ASICs, which are not suitable for low-cost commodity hardware devices. In this paper, we propose a low-cost and low-power embedded solution to provide high speed depth detection. We extend an existing off-the-shelf VLIW
image processor and perform algorithmic and architectural optimizations in order to achieve the requested real-time performance speed. Experimental results show that by adding different functional units and adjusting the algorithm to take full advantage of them, a 640x480 image pair with 64 disparities1 can be processed at 36.75 fps on a single processor instance, which
is an improvement of 23% compared to the best state-of-the-art image processor.@en

High-level synthesis (HLS) is increasingly popular for the design of high-performance and energy-efficient heterogeneous systems, shortening time-to-market and addressing today’s system complexity. HLS allows designers to work at a higherlevel of abstraction by using a software program to specify the
hardware functionality. Additionally, HLS is particularly interesting for designing field-programmable gate array circuits, where hardware implementations can be easily refined and replaced in the target device. Recent years have seen much activity in the HLS research community, with a plethora of HLS tool offerings,
from both industry and academia. All these tools may have different input languages, perform different internal optimizations, and produce results of different quality, even for the very same input description. Hence, it is challenging to compare their performance and understand which is the best for the hardware to be implemented. We present a comprehensive analysis
of recent HLS tools, as well as overview the areas of active interest in the HLS research community. We also present a firstpublished methodology to evaluate different HLS tools. We use our methodology to compare one commercial and three academic tools on a common set of C benchmarks, aiming at performing
an in-depth evaluation in terms of performance and the use of resources.@en