scholarly journals Compiler Generation from Denotational Semantics

1980 ◽  
Vol 9 (113) ◽  
Author(s):  
Neil D. Jones
Keyword(s):  
Programming Languages ◽  
State Transition ◽  
Lambda Calculus ◽  
Denotational Semantics ◽  
Optimization Methods ◽  
Compiler Generation ◽  
Syntax Rule ◽  
Language L ◽  
Algebraic Framework ◽  
Efficient Code

<p>A methodology is described for generating provably correct compilers from denotational definitions of programming languages. An application is given to produce compilers into STM code (an STM or state transition machine is a flow-chart-like program, low-level enough to be translated into efficient code on conventional computers). First, a compiler phi: LAMC -&gt; STM from a lambda calculus dialect is defined. Any denotational definition DD of language L defines a map DD': L -&gt; LAMC, so DD'_circle phi compiles L into STM code. Correctness follows from the correctness of phi.</p><p>The algebraic framework of Morris, ADJ, etc. is used. The set of STMs is given an algebraic structure so any DD'_circ phi may be specified by giving a derived operator on STM for each syntax rule of L.</p><p>This approach yields quite redundant object programs, so the paper ends by describing two flow analytic optimization methods. The first analyzes an already-produced STM to obtain information about its runtime behaviour which is used to optimize the STM. The second analyzes the generated compiling scheme to determine runtime properties of object programs in general which a compiler can use to produce less redundant STMs.</p>

scholarly journals Type-Directed Partial Evaluation

1995 ◽  
Vol 24 (494) ◽  
Author(s):  
Olivier Danvy
Keyword(s):  
Programming Languages ◽  
Code Generation ◽  
Compiler Optimization ◽  
Partial Evaluation ◽  
Lambda Calculus ◽  
Denotational Semantics ◽  
Compiler Generation ◽  
Environment Type ◽  
Symbolic Evaluation ◽  
Specialized Program

<p>We present a strikingly simple partial evaluator, that is type-directed and reifies a compiled program into the text of a residual, specialized program. Our partial evaluator is concise (a few lines) and it handles the flagship examples of offline monovariant partial evaluation. Its source programs are constrained in two ways: they must be closed and monomorphically typable. Thus dynamic free variables need to be factored out in a ``dynamic initial environment´´. Type-directed partial evaluation uses no symbolic evaluation for specialization, and naturally processes static computational effects.</p><p>Our partial evaluator is the part of an offline partial evaluator that residualizes static values in dynamic contexts. Its restriction to the simply typed lambda-calculus coincides with Berger and Schwichtenberg's ``inverse of the evaluation functional´´ (LICS'91), which is an instance of normalization in a logical setting. As such, type-directed partial evaluation essentially achieves lambda-calculus normalization. We extend it to produce specialized programs that are recursive and that use disjoint sums and computational effects. We also analyze its limitations: foremost, it does not handle inductive types.</p><p>This paper therefore bridges partial evaluation and lambda-calculus normalization through higher-order abstract syntax, and touches upon parametricity, proof theory, and type theory (including subtyping and coercions), compiler optimization, and run-time code generation (including decompilation). It also offers a simple solution to denotational semantics-based compilation and compiler generation.</p><p>Proceedings of POPL96, the 1996 ACM Symposium on Principles of Programming Languages (to appear).</p>

scholarly journals Denotational semantics of recursive types in synthetic guarded domain theory

2018 ◽  
Vol 29 (3) ◽  
pp. 465-510 ◽  
Author(s):  
RASMUS E. MØGELBERG ◽  
MARCO PAVIOTTI
Keyword(s):  
Programming Languages ◽  
Type Theory ◽  
Operational Semantics ◽  
Lambda Calculus ◽  
Denotational Semantics ◽  
Domain Theory ◽  
Logical Relation ◽  
Dependent Type Theory ◽  
Semantics Of Programming Languages ◽  
Dependent Type

Just like any other branch of mathematics, denotational semantics of programming languages should be formalised in type theory, but adapting traditional domain theoretic semantics, as originally formulated in classical set theory to type theory has proven challenging. This paper is part of a project on formulating denotational semantics in type theories with guarded recursion. This should have the benefit of not only giving simpler semantics and proofs of properties such as adequacy, but also hopefully in the future to scale to languages with advanced features, such as general references, outside the reach of traditional domain theoretic techniques.Working inGuarded Dependent Type Theory(GDTT), we develop denotational semantics for Fixed Point Calculus (FPC), the simply typed lambda calculus extended with recursive types, modelling the recursive types of FPC using the guarded recursive types ofGDTT. We prove soundness and computational adequacy of the model inGDTTusing a logical relation between syntax and semantics constructed also using guarded recursive types. The denotational semantics is intensional in the sense that it counts the number of unfold-fold reductions needed to compute the value of a term, but we construct a relation relating the denotations of extensionally equal terms, i.e., pairs of terms that compute the same value in a different number of steps. Finally, we show how the denotational semantics of terms can be executed inside type theory and prove that executing the denotation of a boolean term computes the same value as the operational semantics of FPC.

scholarly journals An Abstract Contract Theory for Programs with Procedures

2021 ◽  
pp. 152-171
Author(s):  
Christian Lidström ◽  
Dilian Gurov
Keyword(s):  
Programming Languages ◽  
Contract Theory ◽  
Denotational Semantics ◽  
The Other ◽  
Hoare Logic ◽  
Basic Building Block ◽  
Sequential Programming ◽  
Modular Verification ◽  
The One ◽  
Meta Theory

AbstractWhen developing complex software and systems, contracts provide a means for controlling the complexity by dividing the responsibilities among the components of the system in a hierarchical fashion. In specific application areas, dedicated contract theories formalise the notion of contract and the operations on contracts in a manner that supports best the development of systems in that area. At the other end, contract meta-theories attempt to provide a systematic view on the various contract theories by axiomatising their desired properties. However, there exists a noticeable gap between the most well-known contract meta-theory of Benveniste et al. [5], which focuses on the design of embedded and cyber-physical systems, and the established way of using contracts when developing general software, following Meyer’s design-by-contract methodology [18]. At the core of this gap appears to be the notion of procedure: while it is a central unit of composition in software development, the meta-theory does not suggest an obvious way of treating procedures as components.In this paper, we provide a first step towards a contract theory that takes procedures as the basic building block, and is at the same time an instantiation of the meta-theory. To this end, we propose an abstract contract theory for sequential programming languages with procedures, based on denotational semantics. We show that, on the one hand, the specification of contracts of procedures in Hoare logic, and their procedure-modular verification, can be cast naturally in the framework of our abstract contract theory. On the other hand, we also show our contract theory to fulfil the axioms of the meta-theory. In this way, we give further evidence for the utility of the meta-theory, and prepare the ground for combining our instantiation with other, already existing instantiations.

Documentation Methods for Visual Languages

2011 ◽  
pp. 436-454
Author(s):  
Eduardo Costa ◽  
Alexandre Grings ◽  
Marcus Vinicius dos Santos
Keyword(s):  
Programming Languages ◽  
Denotational Semantics ◽  
Visual Programming ◽  
Visual Adaptation ◽  
Visual Languages

Many people argue that Visual Programming languages are self-documenting. This article points out that there is no such thing as a self-documenting language. Besides this, many popular methods used to document programs written in other languages do not suit Visual Languages perfectly, and need some tailoring. Therefore, the authors propose a visual adaptation of the dataflow method of documentation. They also present versions of instantiated documentation and denotational semantics applied to visual languages. Finally, they present a Prolog based complete example of documentation.

What is a purely functional language?

1998 ◽  
Vol 8 (1) ◽  
pp. 1-22 ◽  
Author(s):  
AMR SABRY
Keyword(s):  
Programming Languages ◽  
Functional Programming ◽  
Denotational Semantics ◽  
Functional Language ◽  
Formal Definition ◽  
Functional Programming Languages ◽  
Precise Meaning ◽  
Definition Of ◽  
Parameter Passing

Functional programming languages are informally classified into pure and impure languages. The precise meaning of this distinction has been a matter of controversy. We therefore investigate a formal definition of purity. We begin by showing that some proposed definitions which rely on confluence, soundness of the beta axiom, preservation of pure observational equivalences and independence of the order of evaluation, do not withstand close scrutiny. We propose instead a definition based on parameter-passing independence. Intuitively, the definition implies that functions are pure mappings from arguments to results; the operational decision of how to pass the arguments is irrelevant. In the context of Haskell, our definition is consistent with the fact that the traditional call-by-name denotational semantics coincides with the traditional call-by-need implementation. Furthermore, our definition is compatible with the stream-based, continuation-based and monad-based integration of computational effects in Haskell. Finally, we observe that call-by-name reasoning principles are unsound in compilers for monadic Haskell.

Sign in / Sign up

Export Citation Format

Share Document