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FPGA prototyping has long been an indispensable technique in pre-silicon verification as well as enabling early-stage software development. FPGAs themselves have also gained popularity as hardware accelerators deployed in datacenters. However, FPGA development brings a plethora of problems. These issues constitute a high barrier towards mass adoption of agile development surrounding FPGA-based projects.To address these problems, we have built Zoomie for fast incremental compilation, reusing verification infrastructure, and a software-inspired approach towards open-source emulation. We show that Zoomie achieves 18\texttimes{} speedup over the vendor toolchain in incremental compilation time for million-gate designs. At the same time, Zoomie also provides a software-like debugging experience with breakpoints, stepping the design, and forcing values in a running design.
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Just-In-Time Compilation for Verilog: A New Technique for Improving the FPGA Programming Experience
FPGAs offer compelling acceleration opportunities for modern applications. However compilation for FPGAs is painfully slow, potentially requiring hours or longer. We approach this problem with a solution from the software domain: the use of a JIT. Code is executed immediately in a software simulator, and compilation is performed in the background. When finished, the code is moved into hardware, and from the user's perspective it simply gets faster. We have embodied these ideas in Cascade: the first JIT compiler for Verilog. Cascade reduces the time between initiating compilation and running code to less than a second, and enables generic printf debugging from hardware. Cascade preserves program performance to within 3× in a debugging environment, and has minimal effect on a finalized design. Crucially, these properties hold even for programs that perform side effects on connected IO devices. A user study demonstrates the value to experts and non-experts alike: Cascade encourages more frequent compilation, and reduces the time to produce working hardware designs.
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- Award ID(s):
- 1846169
- PAR ID:
- 10138854
- Date Published:
- Journal Name:
- Proceedings of the Twenty-Fourth International Conference on Architectural Support for Programming Languages and Operating Systems
- Page Range / eLocation ID:
- 271 to 286
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Conference Paper:
- https://doi.org/10.1145/3297858.3304010
