With the increased interest in energy efficiency, a lot of application domains experiment with Field Programmable Gate Arrays (FPGAs), which promise customized hardware accelerators with high-performance and low power consumption. These experiments possible due to the development of High-Level Languages (HLLs) for FPGAs, which permit non-experts in hardware design languages (HDLs) to program reconfigurable hardware for general purpose computing. However, some of the expert knowledge remains difficult to integrate in HLLs, eventually leading to performance loss for HLL-based applications. One example of such a missing feature is the efficient exploitation of the local memories on FPGAs. A solution to address this challenge is PolyMem, an easy-to-use polymorphic parallel memory that uses BRAMs. In this work, we present HLS-PolyMem, the first complete implementation and in-depth evaluation of PolyMem optimized for the Xilinx Design Suite. Our evaluation demonstrates that HLS-PolyMem is a viable alternative to HLS memory partitioning, the current approach for memory parallelism in Vivado HLS. Specifically, we show that PolyMem offers the same performance as HLS partitioning for simple access patterns, and outperforms partitioning as much as 13x when combining multiple access patterns for the same data structure. We further demonstrate the use of PolyMem for two different case studies, highlighting the superior capabilities of HLS-PolyMem in terms of performance, resource utilization, flexibility, and usability. Based on all the evidence provided in this work, we conclude that HLS-PolyMem enables the efficient use of BRAMs as parallel memories, without compromising the HLS level or the achievable performance.

To handle the stringent performance requirements of future exascale-class applications, High Performance Computing (HPC) systems need ultra-efficient heterogeneous compute nodes. To reduce power and increase performance, such compute nodes will require hardware accelerators with a high degree of specialization. Ideally, dynamic reconfiguration will be an intrinsic feature, so that specific HPC application features can be optimally accelerated, even if they regularly change over time. In the EXTRA project, we create a new and flexible exploration platform for developing reconfigurable architectures, design tools and HPC applications with run-time reconfiguration built-in as a core fundamental feature instead of an add-on. EXTRA covers the entire stack from architecture up to the application, focusing on the fundamental building blocks for run-time reconfigurable exascale HPC systems: new chip architectures with very low reconfiguration overhead, new tools that truly take reconfiguration as a central design concept, and applications that are tuned to maximally benefit from the proposed run-time reconfiguration techniques. Ultimately, this open platform will improve Europe's competitive advantage and leadership in the field.

Abstract The FASTER (Facilitating Analysis and Synthesis Technologies for Effective Reconfiguration) EU FP7 project, aims to ease the design and implementation of dynamically changing hardware systems. Our motivation stems from the promise reconfigurable systems hold for achieving high performance and extending product functionality and lifetime via the addition of new features that operate at hardware speed. However, designing a changing hardware system is both challenging and time-consuming. FASTER facilitates the use of reconfigurable technology by providing a complete methodology enabling designers to easily specify, analyze, implement and verify applications on platforms with general-purpose processors and acceleration modules implemented in the latest reconfigurable technology. Our tool-chain supports both coarse- and fine-grain FPGA reconfiguration, while during execution a flexible run-time system manages the reconfigurable resources. We target three applications from different domains. We explore the way each application benefits from reconfiguration, and then we asses them and the FASTER tools, in terms of performance, area consumption and accuracy of analysis.

To handle the stringent performance requirements of future exascale-class applications, High Performance Computing (HPC) systems need ultra-efficient heterogeneous compute nodes. To reduce power and increase performance, such compute nodes will require hardware accelerators with a high degree of specialization. Ideally, dynamic reconfiguration will be an intrinsic feature, so that specific HPC application features can be optimally accelerated, even if they regularly change over time. In the EXTRA project, we create a new and flexible exploration platform for developing reconfigurable architectures, design tools and HPC applications with run-time reconfiguration built-in as a core fundamental feature instead of an add-on. EXTRA covers the entire stack from architecture up to the application, focusing on the fundamental building blocks for run-time reconfigurable exascale HPC systems: new chip architectures with very low reconfiguration overhead, new tools that truly take reconfiguration as a central design concept, and applications that are tuned to maximally benefit from the proposed run-time reconfiguration techniques. Ultimately, this open platform will improve Europe's competitive advantage and leadership in the field.

Even though FPGAs are becoming more and more popular as they are used in many different scenarios like communications and HPC, the steep learning curve needed to work with this technology is still the major limiting factor to their full success. Many works proposed to mitigate this problem by creating a companion of tools to support the designer during the development phase for this technology. The EU FASTER Project aims at realizing an integrated toolchain that assists the designer in the steps of the design flow that are necessary to port a given application onto an FPGA device. The novelty of the framework relies in the fact that the partial dynamic reconfiguration, which FPGA devices can exploit, is seen as a first class citizen throughout the whole design flow. This work reports a case study in which the FASTER toolchain has been used to port a raytracer application onto the STM Spear prototyping embedded platform. The paper discusses the steps done for the realization of the prototype and the results obtained on the target device. It finally reports some improvements that can be exploited to improve the performance of the hardware implementation that has been realized.

While fine-grain, reconfigurable devices have been available for years, they are mostly used in a fixed functionality, "asic-replacement" manner. To exploit opportunities for flexible and adaptable run-time exploitation of fine grain reconfigurable resources (as implemented currently in dynamic, partial reconfiguration), better tool support is needed. The FASTER project aims to provide a methodology and a tool-chain that will enable designers to efficiently implement a reconfigurable system on a platform combining software and reconfigurable resources. Starting from a high-level application description and a target platform, our tools analyse the application, evaluate reconfiguration options, and implement the designer choices on underlying vendor tools. In addition, FASTER addresses micro-reconfiguration, verification, and the run-time management of system resources. We use industrial applications to demonstrate the effectiveness of the proposed framework and identify new opportunities for reconfigurable technologies.

Current and future computing systems increasingly require that their functionality stays flexible after the system is operational, in order to cope with changing user requirements and improvements in system features, i.e. changing protocols and data-coding standards, evolving demands for support of different user applications, and newly emerging applications in communication, computing and consumer electronics. Therefore, extending the functionality and the lifetime of products requires the addition of new functionality to track and satisfy the customers needs and market and technology trends. Many contemporary products along with the software part incorporate hardware accelerators for reasons of performance and power efficiency. While adaptivity of software is straightforward, adaptation of the hardware to changing requirements constitutes a challenging problem requiring delicate solutions. The FASTER (Facilitating Analysis and Synthesis Technologies for Effective Reconfiguration) project aims at introducing a complete methodology to allow designers to easily implement a system specification on a platform which includes a general purpose processor combined with multiple accelerators running on an FPGA, taking as input a high-level description and fully exploiting, both at design time and at run time, the capabilities of partial dynamic reconfiguration. The goal is that for selected application domains, the FASTER toolchain will be able to reduce the design and verification time of complex reconfigurable systems providing additional novel verification features that are not available in existing tool flows.

During the last few years, there is an increasing interest in mixing software and hardware to serve efficiently different applications. This is due to the heterogeneity characterizing the tasks of an application which require the presence of resources from both worlds, software and hardware. Controlling effectively these resources through an integrated tool flow is a challenging problem and towards this direction only a few efforts exist. In fact, a framework that seamlessly exploits both resources of a platform for executing efficiently an application has not yet come into existence. Moreover, reconfigurable computing often incorporated in such platforms due to its high flexibility and customization, has not yet taken off due to the lack of exploiting its full capabilities. Thus, the capability of reconfigurable devices such as Field Programmable Gate Arrays (FPGAs) to be dynamically reconfigured, i.e. reprogramming part of the chip while other parts of the same chip remain functional, has not yet taken off even in small-scale basis. The inherent difficulty in using the tools to control this technology has kept it back from being adopted by academia and industry alike. The FASTER (Facilitating Analysis and Synthesis Technologies for Effective Reconfiguration) project aims at introducing a design methodology and a tool flow that will enable designers to implement effectively and easily a system specification on a platform combining software and reconfigurable resources. The FASTER framework accepts as input a high-level description of the application and the architectural details of the target platform, and through certain steps it can enable the full use of the capabilities of the platform, while at the same time it should be flexible enough so as to balance efficiently performance, power and area. One of the main novelties is the incorporation of partial reconfiguration as an explicit design concept at an early stage of the design flow. We target different applications from the embedded, desktop and high-performance computing domains. In all cases we will demonstrate the effectiveness of the proposed framework in exploiting the inherent parallelism of applications and enabling the runtime adaptation of the platforms to the changing needs of the applications.