Path-based and graph-based timing analysis software

Leipzig university, leipzig, germany matteo fischer leipzig university, leipzig, germany abstract graphs are a suitable representation of software artifacts data created during development and maintenance activities. Our methodology operates using graphbased analysis gba principles. You might be thinking that this is not accurate means why in gba we missed 2. These methods require algorithms for minmaxsum calculations for cell pin arrival and pintopin delay arcs.

Static timing analysis sta using eda tool part1 vlsi. In sta static timing analysis during delay calculation of any path, tool has 2 approaches. Graph based analysis, or gba path based analysis, or pba. In pathbased analysis, the slew from the pin along the path. How depth and distance calculations vary in graph based. William shu university of california san diego palo.

Ssp 2019 graphbased analysis and visualization of software traces information systems institute, software engineering department kieker framework to monitor, analyze, and visualize software behavior supports eventbased and statebased monitoring usable with java. Schedulability analysis and software synthesis for graph. After several years of physical design i moved into timing signoff methodology. Finally, tighter correlation of graphbased analysis gba to pathbased analysis pba, achieved through parametric onchip variation pocv technology, means designers can spend less. Such as, in graphbased watermarking and its derivatives 16, 21, 24, payload widgets were designed to have nothing else to do with the subject software except being attached to it. This paper demonstrates that it is possible and practical to perform pathbased statistical static timing analysis, and that such an analysis can be written compactly in matrix notation, allowing the use of. The timing analysis engine establishes a timing graph defining a plurality of timing paths through different subsections of the electronic circuit design. Eda vendors should improve the runtime performance of path. Jun 04, 2018 using machine learning to predict path based slack from graph based timing analysis.

Suggestions for ways to model a graph with shared nodes but has a unique path based on. Path based graph based analysis now once you will choose the type of analysis, next is whether your timing analysis tool support these type of analysis and till what accuracy. During the sta, both graphbased timing analysis gba and path based. Method and system for timing analysis with adaptive timing. Most timing analysis tools use graph based analysis gba. Static timing analysis sta is a simulation method of computing the expected timing of a digital circuit without requiring a simulation of the full circuit highperformance integrated circuits have. Static timing analysis sta is a simulation method of computing the expected timing of a digital circuit without requiring a simulation of the full circuit highperformance integrated circuits have traditionally been characterized by the clock frequency at which they operate. Tsmc and oip ecosystem partners deliver 16finfet and 3d ic. Timing analysis and optimization techniques for vlsi circuits. With its massively parallel approach, tempus makes pba affordable.

Using machine learning to predict pathbased slack from graph. However, timing analysis for such general task model with mixed execution of preemptive and nonpreemptive jobs is yet to be. In anticipation of designers future timing closure challenges, synopsys continues to offer smarter, more efficient technology, said robert hoogenstryd, senior director of marketing for design analysis and signoff tools at. Readings in hardwaresoftware codesign presents the papers that have shaped the hardwaresoftware codesign field since its inception in the early 90s. One embodiment of the present invention provides a system that performs an efficient pathbased static timing analysis sta in a circuit design. Pre and postsilicon techniques to deal with largescale process variations jaeyong chung, ph. Using machine learning to predict pathbased slack from graphbased timing analysis andrew b. Department of electronic engineering incheon national university. Embodiments may further include invoking a pathbased analysis pba on the worst timing path and determining if the worst timing path satisfies the pba analysis.

New primetime technology significantly improves turnaround time tat and power reduction, while providing smarter utilization of compute resources. The tool takes the actual slew values, so the calculated delays are actual delays. As ic design moves into 20nm and 16nm nodes, the challenges facing not only. William shu university of california san diego palo alto.

Path based analysis and graph based analysis correlation to improve timing closure in automatic place and route apr. It can only be applied on user specified timing paths. If pathbased analysis pba runtimes can be improved by significant. For additional information, visit the synopsys galaxy signoff solution page, watch one of the many webinars or. In case of pba path base analysis, we are using actual delay between input pin and output combination means choosing both combination of delay. Primetime advanced timing analysis user guide version f2011. Pre and postsilicon techniques to deal with largescale process variations. It uses the worst input slew of a cell to calculate that cells output transition. During sta, models of the expected timing of a digital circuit are created by estimating the expected delay within the circuit, for example, via an anticipated worst case signal path. Readings in hardwaresoftware codesign sciencedirect. In this paper, we show that path based techniques are not scalable, due to the enormous number of paths in modern designs, and can also result in incorrect results.

The latest in static timing analysis with variation modeling. In this paper, we show that pathbased techniques are not scalable, due to the enormous number of paths in modern designs, and can also result in incorrect results. An accurate sparsematrix based framework for statistical. Graphbased dynamic analysis proceedings of the ieeeacm. Timing analysis and optimization techniques need to consider each of them and also their interactions. Synopsys primetime speeds timing and power closure for. In graph based analysis, the worst slew of all input pins is used, which often results in a getting a worse value in the lookup table. The d i path depth depends on whether graph based timing or path based timing analysis is used. Austin, texasyou want the bad news first or the good news about ic design challenges. Pathbased analysis and graphbased analysis correlation to improve timing closure in automatic place and route apr. Download citation on nov 1, 2015, hari cherupalli and others published graph based dynamic analysis. Method and apparatus for integrating spicebased timing.

Learning to predict pathbased slack from graphbased timing analysis 12001215, closing contacts. Kaustav guha lead member consulting staff mentor graphics. The d i path depth depends on whether graphbased timing or pathbased timing analysis is used. Us20160070844a1 selectively reducing graph based analysis. Embodiments may further include invoking a path based analysis pba on the worst timing path and determining if the worst timing path satisfies the pba analysis. During operation, the system identifies a set of paths within. The slack calculated with this method is accurate but pba takes a longer runtime. Mar 23, 2016 finally, tighter correlation of graph based analysis gba to path based analysis pba, achieved through parametric onchip variation pocv technology, means designers can spend less time doing runtimecostly pba analysis to eliminate false violations. Path base analysis pba vs graph base analysis gba part1. Us8079004b2 efficient exhaustive pathbased static timing. Since k is calculated from a graphbased aocv number, it depends on path depth. Its more pessimistic than pathbased analysis pba, but the latter is more. Pre and postsilicon techniques to deal with largescale.

As such most of the analysis type is common and all the tools support these. This relates to primetimes different modes of analysis. Since timing is the heart beat of any chip, thorough understanding of timing concepts, development of timing constraints are given through this sta training especially when it comes to ultra deep. There are many statistical timing analysis researches to handle the problems introduced by process variations, but how to get the bounds of timing yield and how to use these techniques to verify the clock validity still need investigations. Download citation on nov 1, 2015, hari cherupalli and others published graphbased dynamic analysis. A method, system or computer usable program product for improving a circuit design having a set of endpoint circuits including identifying a subset of the set of endpoint circuits for further timing analysis based on graph based analysis gba of the circuit design. How depth and distance calculations vary in graph based and. In my project, for timing analysis using primetime, first graph based analysis is used and then path based analysis. The delays of paths by pba are calculated path by path and are accurate.

Most timing analysis tools use graphbased analysis. Nov 07, 2017 path base analysis pba vs graph base analysis gba part1 today, we are going to discuss about the path base analysis vs graph base analysis. As such difference is more complex compare to what i am going to explain, but right now its sufficient to start with. It also supports graph based and path based analysis and optimisation and advanced signal integrity and noise analysis. In order to develop a mapreduce program, computations that can be issued to.

Static timing analysis path based analysis 0 distance measurement through microcontroller based distance meter circuit 3 re. Here is an excellent article from ian robinson blog about timebased versioned graphs basically the article. Finally, tighter correlation of graph based analysis gba to path based analysis pba, achieved through parametric onchip variation pocv technology, means designers can spend less time doing. Using machine learning to predict pathbased slack from graphbased timing analysis. This software release helps ensure chip designers can meet demanding signoff schedules at advanced process nodes. Dec 08, 2016 since k is calculated from a graph based aocv number, it depends on path depth.

Graphbased sta for asynchronous controllers ieee conference. Yan solihin university of central florida, usa contact. Its more pessimistic than path based analysis pba, but the latter is more computationally demanding, and that has limited the use of pba. Hypergraphbased connectivity measures for signaling pathway. Synopsys primetime speeds timing and power closure for complex soc. Jan 30, 2018 the system also comprises a timing analysis engine configured to execute a predetermined static timing analysis based upon the input models acquired from the data storage portion.

Is there an exampleresourcearticle which describes this for neo4j or any other graph db. Graphbased analysis and visualization of software traces. Jul 26, 2012 path based graph based analysis now once you will choose the type of analysis, next is whether your timing analysis tool support these type of analysis and till what accuracy. In graph based analysis, the worst slew propagation is on, and the timing engine computes the worst case delays of all standard cells assuming. Using machine learning to predict pathbased slack from. Gate timing arc delayslew computation, inputoutput environment constraints, and path delay propagation, are implemented based on gba sta principles. This paper demonstrates that it is possible and practical to perform path based statistical static timing analysis, and that such an analysis can be written compactly in matrix notation, allowing the use of standard highly optimized linear algebra techniques. This software release helps ensure chip designers can meet. For path based timing analysis, d i has a smaller path depth than d g. Efficient characterization of dynamic timing and activity distributions find, read and cite. We propose a graph based technique for performing dynamic timing and activity analysis of a workload on a processor that addresses the limitations of path based techniques. In anticipation of designers future timing closure challenges, synopsys continues to offer smarter, more efficient technology, said robert hoogenstryd, senior director of marketing for design analysis and signoff tools at synopsys. The method of claim 8, wherein each segment in the path is associated with a graph based delay and a graph based slew which was previously computed for the path based on a graph based sta, wherein the graph based delay and the graph based slew provide the worstcase estimation for a path based delay and a path based slew associated with the path. Its more pessimistic than pathbased analysis pba, but the latter is more computationally demanding, and that has limited the use of pba.

The summit provided closer looks at pathbased analysis, timing closure for. Learning to predict path based slack from graph based timing analysis 12001215, closing contacts. Hypergraphbased connectivity measures for signaling. Pederson, spice simulation program with integrated circuit. Method and apparatus for integrating spicebased timing using. Pba is not utilized by implementation tools, to save runtime, but can be used by timing tools to get accurate results.

The method comprises initiating a timing signal at the common. Sta training is designed to make the engineer or designer understand the complete timing signoff strategies for successful and confident tapeout of the design to the semiconductor fabrication house. The estimation of the expected delay may be based on graph based analysis gba or path based analysis pba. Analyze timing path by path instead of single points. Scalable nworst algorithms for dynamic timing and activity. Mar 23, 2016 this software release helps ensure chip designers can meet demanding signoff schedules at advanced process nodes. Figure 3 shows the runtime scalability versus different core thread counts, and detailed pro. The main sta network timing methods are graphbased analysis gba and pathbased analysis pba, which should always be bounded by a gba calculation. Related work most previous works that perform dynamic timing and activity analysis for btwc design and optimization use pathbased tools. Tsmc and oip ecosystem partners deliver 16finfet and 3d ic reference flows. The embedded timer correlates with signoff timing tools and supports various onchip variation methods, including aocv, sbocv, socv and lvf.

A lazy eviction algorithm for ssd cache in cloud block storage. A method for performing graph based static timing analysis comprises reading in a design of an integrated circuit having a subset of timing paths, each timing path of the subset having a common point, wherein the common point is identical for all timing paths of the subset. Opentimer shell interprets each command in three forms, builder, action, and accessor. In path based analysis, the slew from the pin along the path. Gba graphbased analysis takes linear time in circuit size pba pathbased analysis takes exponential time in circuit size. Timing analysis patents and patent applications class 716. My understanding is that now aocv distance depth is applied on it. A method for performing graphbased static timing analysis comprises reading in a design of an integrated circuit having a subset of timing paths, each timing path of the subset. During the sta, both graphbased timing analysis gba and pathbased. Most timing analysis tools use graphbased analysis gba. In anticipation of designers future timing closure challenges, synopsys. For graph based timing analysis, d i has the same path depth as dg.

Pathbased timing analysis pba is a pivotal step to achieve accurate timing signoff. Basic statements, like variable declarations, assignments, and procedure calls, are represented by program vertices in pdgs. A method, system or computer usable program product for improving a circuit design having a set of endpoint circuits including identifying a subset of the set of endpoint circuits for further timing. The system also comprises a timing analysis engine configured to execute a predetermined static timing analysis based upon the input models acquired from the data storage. Tempus provides physicallyaware optimization, hierarchical or flat eco generation, and integrated signalintegrity analysis. Such as, in graph based watermarking and its derivatives 16, 21, 24, payload widgets were designed to have nothing else to do with the subject software except being attached to it. In graphbased analysis, the worst slew of all input pins is used, which often results in a getting a worse value in the lookup table. Background a program dependence graph pdg is a graph representation of the source code of a procedure 4.