A Survey on Performance Optimization of High-Level Synthesis Tools

Field-programmable gate arrays(FPGAs)have recently evolved as a valuable component of the heterogeneous computing.The register transfer level(RTL)design flows demand the designers to be experienced in hardware,resulting in a possible failure of time-to-market.High-level synthesis(HLS)permits designers to work at a higher level of abstraction through synthesizing high-level language programs to RTL descriptions.This provides a promising approach to solve these problems.However,the performance of HLS tools still has limitations.For example,designers remain exposed to various aspects of hardware design,development cycles are still time consuming,and the quality of results(QoR)of HLS tools is far behind that of RTL flows.In this paper,we survey the literature published since 2014 focusing on the performance optimization of HLS tools.Compared with previous work,we extend the scope of the performance of HLS tools,and present a set of three-level evaluation criteria,covering from ease of use of the HLS tools to promotion on specific metrics of QoR.We also propose performance evaluation equations for describing the relation between the performance optimization and the QoR.We find that it needs more efforts on the ease of use for efficient HLS tools.We suggest that it is better to draw an analogy between the HLS development process and the embedded system design process,and to provide more elastic HLS methodology which integrates FPGAs virtual machines.

Determination of symptoms associated with hiesho among young females using hie rating surveys

Objective： Hie （cold sensation） is one of the most well-known health complaints in Japan and elsewhere in East Asia. Those who suffer from severe hie are considered to have hiesho （cold disorder）. This study was conducted to determine symptoms associated with hie in young females using a survey consisting of the hie scale and hie diary. Methods： Two hundred and seventy-one participants were included for the analysis. Survey forms were distributed to the participants. Diagnosis of hiesho was determined by using the hie scale. A discriminant score of over -0.38 was considered hiesho. The Short Form-8 Health Survey Standard Version （SF-8） was used to measure health-related quality of life （QOL）. The participants were also asked to respond to the questionnaire evaluating 14 physical and emotional symptoms, utilizing a six-level Likert scale item. Results： The 1st factor （hie factor） was correlated with hie （r= 0.546）, dry mouth （r= 0.332）, lower- extremity edema （r = 0.450）, headrushes （r=0.470）, shoulder stiffness （r = 0.311 ）, headrushes with chills （r = 0.726）, and fatigue （r= 0.359）. Cronbach＇s α of the 1st factor was 0.748, which indicated reliability between the items. When hie factor was the dependent variable, standardized partial regression coefficient was β=-0.387 for physical component score （P 〈 0.001） and β=-0.243 for mental component score （P 〈 0.001 ）. Conclusion： This study indicated that hiesho symptoms among young female adults were associated with bodily pain and general health perceptions of the SF-8 QOL survey.