research-article

Semantic reasoning about the sea of nodes

Authors:

Delphine Demange,

Yon Fernández de Retana,

David PichardieAuthors Info & Claims

CC 2018: Proceedings of the 27th International Conference on Compiler Construction

Pages 163 - 173

https://doi.org/10.1145/3178372.3179503

Published: 24 February 2018 Publication History

Abstract

The Sea of Nodes intermediate representation was introduced by Cliff Click in the mid 90s as an enhanced Static Single Assignment (SSA) form. It improves on the initial SSA form by relaxing the total order on instructions in basic blocks into explicit data and control dependencies. This makes programs more flexible to optimize. This graph-based representation is now used in many industrial-strength compilers, such as HotSpot or Graal. While the SSA form is now well understood from a semantic perspective -- even formally verified optimizing compilers use it in their middle-end -- very few semantic studies have been conducted about the Sea of Nodes.

This paper presents a simple but rigorous formal semantics for a Sea of Nodes form. It comprises a denotational component to express data computation, and an operational component to express control flow. We then prove a fundamental, dominance-based semantic property on Sea of Nodes programs which determines the regions of the graph where the values of nodes are preserved. Finally, we apply our results to prove the semantic correctness of a redundant zero-check elimination optimization. All the necessary semantic properties have been mechanically verified in the Coq proof assistant.

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Cited By

Herklotz YWickerson J(2024)Hyperblock Scheduling for Verified High-Level SynthesisProceedings of the ACM on Programming Languages10.1145/36564558:PLDI(1929-1953)Online publication date: 20-Jun-2024
https://dl.acm.org/doi/10.1145/3656455
Lesbre DLemerre M(2024)Compiling with Abstract InterpretationProceedings of the ACM on Programming Languages10.1145/36563928:PLDI(368-393)Online publication date: 20-Jun-2024
https://dl.acm.org/doi/10.1145/3656392
Kwon SKwon JKang WLee JHeo KRoychoudhury APaiva AAbreu RStorey M(2024)Translation Validation for JIT Compiler in the V8 JavaScript EngineProceedings of the IEEE/ACM 46th International Conference on Software Engineering10.1145/3597503.3639189(1-12)Online publication date: 20-May-2024
https://dl.acm.org/doi/10.1145/3597503.3639189
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Index Terms

Semantic reasoning about the sea of nodes
1. Software and its engineering
  1. Software creation and management
    1. Software verification and validation
      1. Formal software verification
  2. Software notations and tools
    1. Compilers
    2. Formal language definitions

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Published In

cover image ACM Conferences

CC 2018: Proceedings of the 27th International Conference on Compiler Construction

February 2018

206 pages

ISBN:9781450356442

DOI:10.1145/3178372

General Chair:
Christophe Dubach
University of Edinburgh, UK
,
Program Chair:
Jingling Xue
University of New South Wales, Australia

Copyright © 2018 ACM.

Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than the author(s) must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected].

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Published: 24 February 2018

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CGO '18: 16th Annual IEEE/ACM International Symposium on Code Generation and Optimization

February 24 - 25, 2018

Vienna, Austria

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Cited By

Herklotz YWickerson J(2024)Hyperblock Scheduling for Verified High-Level SynthesisProceedings of the ACM on Programming Languages10.1145/36564558:PLDI(1929-1953)Online publication date: 20-Jun-2024
https://dl.acm.org/doi/10.1145/3656455
Lesbre DLemerre M(2024)Compiling with Abstract InterpretationProceedings of the ACM on Programming Languages10.1145/36563928:PLDI(368-393)Online publication date: 20-Jun-2024
https://dl.acm.org/doi/10.1145/3656392
Kwon SKwon JKang WLee JHeo KRoychoudhury APaiva AAbreu RStorey M(2024)Translation Validation for JIT Compiler in the V8 JavaScript EngineProceedings of the IEEE/ACM 46th International Conference on Software Engineering10.1145/3597503.3639189(1-12)Online publication date: 20-May-2024
https://dl.acm.org/doi/10.1145/3597503.3639189
Čugurović MVujošević Janičić MJovanović VWürthinger T(2024)GraalSP: Polyglot, efficient, and robust machine learning-based static profilerJournal of Systems and Software10.1016/j.jss.2024.112058213(112058)Online publication date: Jul-2024
https://doi.org/10.1016/j.jss.2024.112058
Webb BHayes IUtting MKrebbers RTraytel DPientka BZdancewic S(2023)Verifying Term Graph Optimizations using Isabelle/HOLProceedings of the 12th ACM SIGPLAN International Conference on Certified Programs and Proofs10.1145/3573105.3575673(320-333)Online publication date: 11-Jan-2023
https://dl.acm.org/doi/10.1145/3573105.3575673
Lemerre M(2023)SSA Translation Is an Abstract InterpretationProceedings of the ACM on Programming Languages10.1145/35712587:POPL(1895-1924)Online publication date: 11-Jan-2023
https://dl.acm.org/doi/10.1145/3571258
Utting MWebb BHayes I(2023)Differential Testing of a Verification Framework for Compiler Optimizations (Case Study)2023 IEEE/ACM 11th International Conference on Formal Methods in Software Engineering (FormaliSE)10.1109/FormaliSE58978.2023.00015(66-75)Online publication date: May-2023
https://doi.org/10.1109/FormaliSE58978.2023.00015
Pompougnac HBeaugnon UCohen AButucaru D(2022)Weaving Synchronous Reactions into the Fabric of SSA-form CompilersACM Transactions on Architecture and Code Optimization10.1145/350670619:2(1-25)Online publication date: 8-Mar-2022
https://dl.acm.org/doi/10.1145/3506706
Bourke TJeanmaire PPesin BPouzet M(2021)Verified Lustre Normalization with Node SubsamplingACM Transactions on Embedded Computing Systems10.1145/347704120:5s(1-25)Online publication date: 22-Sep-2021
https://dl.acm.org/doi/10.1145/3477041
Lim HKobourov S(2021)Visualizing JIT Compiler GraphsGraph Drawing and Network Visualization10.1007/978-3-030-92931-2_10(138-146)Online publication date: 23-Dec-2021
https://doi.org/10.1007/978-3-030-92931-2_10
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