R. Giacobazzi. Semantic Aspects of Logic Program Analysis. PhD thesis, Dipartimento di Informatica, Universit`a di Pisa, 1992.  Home/Search   Document Not in Database   Summary   Related Articles   Check

....empty) conjunction of atoms b 1 ; b n and b; b 0 denotes the conjunction b 1 ; b m ; b 0 1 ; b 0 n . For a comprehensive description of abstract interpretation see [8] For a comprehensive description of term systems, closed semirings and constraints systems see [17]. In this paper we consider Constraint Logic Programs over a generic constraint system A (CLP(A) 2 The basic framework When we want to formalize program execution we must take into account, in addition to the inference rules which specify how derivations are made, the properties we observe in a ....

....a denotation modeling SLD trees. We follow the approach in [14, 2] by first defining a syntactic semantic domain ( interpretation) Our modeling of SLD trees is essentially the basic denotation defined in terms of clauses in [11, 15] extended to handle constraint systems in the style of [17, 19, 20]. In the following for the sake of simplicity we consider the PROLOG leftmost selection rule (denoted by lm) All our results can be generalized to local selection rules [22] Let us consider the equivalence relation of variance extended to nodes j. Definition 2.4 A interpretation I is an ....

[Article contains additional citation context not shown here]

R. Giacobazzi. Semantic Aspects of Logic Program Analysis. PhD thesis, Dipartimento di Informatica, Universit`a di Pisa, 1992.

....system, mantaining the logical flavor of classical semantics for pure logic programming. 1 Introduction An elegant and promising technique for analyzing logic programs is that based on constraints, first introduced in [3] and then formalized in terms of the so called generalized semantics in [6, 7, 5]. The extension of logic programming ( 15] that replaces the usual unification on the Herbrand universe with a more general notion of constraint is called constraint logic programming (CLP, 8] The semantics of CLP is usually given in terms of algebraic structures, called constraint systems ....

R. Giacobazzi. Semantic Aspects of Logic Program Analysis. PhD thesis, Dipartimento di Informatica, Universit`a di Pisa, 1992.

....for example, the stable model and the well founded model semantics) by showing that it preserves the semantic kernel considered in section 6.3. 7. 2 Program analysis In the area of program analysis, the s semantics has been used as a foundation of several frameworks for abstract interpretation [13, 65, 77, 31]. Abstract interpretation is inherently semantics sensitive and different semantic definition styles lead to different approaches to program analysis. In the case of logic programs (see [38] for a broad overview) two main approaches exist, namely the top down and the bottom up ones [94] The most ....

....at least some of the above semantics have successfully been used to solve real problems. As shown in [59, 52] the various semantics are mutually related by means of abstractions. The same relation holds between concrete and abstract semantics. In particular, the generalized semantics of CLP in [66, 65] shows that one can derive from a single semantics several specializations obtained by abstracting the constraints in the program. One interesting open research problem, which is currently under investigation, is whether the approach can be extended to cope with the various concrete observables. ....

R. Giacobazzi. Semantic Aspects of Logic Program Analysis. PhD thesis, Dipartimento di Informatica, Universit`a di Pisa, 1992.

.... is a family of rule based constraint programming languages firstly defined in [7] The instance of this scheme we are interested in, is the CLP(R) language [8] Stan is a CLP(R) static analyzer based on abstract interpretation [2, 3] The core of the concrete semantics is the unfolding operator [6]. The main advantage of using this operator is the possibility to use the same function for both forward (top down) and backward (bottom up) analysis. The constraint space is approximated by convex polyhedra. A specific widening operator for polyhedra [4] is introduced to accelerate the ....

R. Giacobazzi, Semantic aspects of Logic Program Analysis. Ph.D. Dissertation, Universit`a di Pisa, March 1993

....structure. We discuss the conditions under which the second abstraction is not needed. 1 Introduction An elegant and promising technique for analyzing logic programs is that based on constraints, first introduced in [15] and then formalized in terms of the so called generalized semantics in [26, 27, 25]. The main features of the technique are the following. ffl The abstraction can simply be performed by abstracting the (concrete) constraint system into an abstract constraint system. The correctness of the analysis is expressed in terms of simple properties of the two constraint systems. ffl A ....

....on the contrary, can widely be developed in constraint and analysis independent way. It is worth noting that problems of sequences approximation were found in areas which are apparently loosely related to the problem of approximating the control. This is the case of the compositional analysis [25, 10, 23] and of the analysis of concurrent logic programs [13, 14] As we will show in Section 5.3, in several cases the approximation of the simple constraints together with the elimination of multiple constraint occurrences in the sequence, guarantees that the fixpoint is obtained in a finite number ....

R. Giacobazzi. Semantic Aspects of Logic Program Analysis. PhD thesis, Dipartimento di Informatica, Universit`a di Pisa, 1992.

No context found.

R. Giacobazzi. Semantic Aspects of Logic Program Analysis. PhD thesis, Dipartimento di Informatica, Universit`a di Pisa, 1992.

.... program analysis has been firstly addressed in [8] by introducing a framework which is based on the compositional semantics F , and which formalizes the analysis in terms of the standard theory of abstract interpretation ( 12] In this section we briefly introduce some notions and results from [8, 18]. For the sake of completeness, we include in the appendix the proofs of those results which are relevant for abductive analysis. We follow [8] by assuming that (Int ; ff; AInt ; fl) is a Galois insertion, and that the abstract semantics F : AInt AInt safely mimics F , i.e. for each I 2 Int : ....

....to contain at most one occurrence of each (open) predicate symbol. In this case, since Pi is usually finite, the domain of abstract interpretations AInt results a finite height lattice. The abstracted compositional semantics is denoted F . This semantics is compositional correct (see [8, 18]) therefore, by Theorem 4.13, it can be correctly used in abstract abduction. The abstraction is specific for some abstract domain for analysis. We will see the case for ground dependencies in Example 5.3 below. The approach in [17] is instead oriented to provide a compositional complete ....

[Article contains additional citation context not shown here]

R. Giacobazzi. Semantic Aspects of Logic Program Analysis. PhD thesis, Dipartimento di Informatica, Universit`a di Pisa, 1993. TD -- 18/93. URL http://www.di.unipi.it/giaco/papers.html.

....dependencies between modules and one might have to strengthen the abstract domain to enhance its capability to support compositional analysis. Similar properties are required by a domain to support goal independent analyses as described in [10] The technical proofs for our results can be found in [21]. 2 Preliminaries In the following we assume familiarity with the standard definitions and notation for logic programs [27] constraint logic programs [26] and abstract interpretation [15] Throughout, we assume a fixed set of function symbols Sigma, a fixed set of predicate symbols Pi and a ....

R. Giacobazzi. Semantic Aspects of Logic Program Analysis. Ph.D. Thesis, Dipartimento di Informatica, University of Pisa, TD-18/93, 1993. (URL: http://www.di.unipi.it/giaco/papers.html)

.... program analysis has been firstly addressed in [8] by introducing a framework which is based on the compositional semantics F , and which formalizes the analysis in terms of the standard theory of abstract interpretation ( 12] In this section we briefly introduce some notions and results from [8, 17]. For the sake of completeness, we include in the appendix the proofs of 6 those results which are relevant for abductive analysis. We follow [8] by assuming that (Int ; ff; AInt v ; fl) is a Galois insertion, and that the abstract semantics F A : AInt AInt safely mimics F , i.e. for each I ....

....to contain at most one occurrence of each (open) predicate symbol. In this case, since Pi is usually finite, the domain of abstract interpretations AInt results a finite height lattice. The abstracted compositional semantics is denoted F A . This semantics is compositional correct (see [8, 17]) therefore, by Theorem 4.10, it can be correctly used in abstract abduction. The abstraction is specific for some abstract domain for analysis. We will see the case for ground dependencies in Example 12 below. The approach in [16] is instead oriented to provide a compositional complete ....

[Article contains additional citation context not shown here]

R. Giacobazzi. Semantic Aspects of Logic Program Analysis. PhD thesis, Dipartimento di Informatica, Universit`a di Pisa, 1993. TD -- 18/93. URL http://www.di.unipi.it/giaco/papers.html.

.... b n fi fi fi fi fi fi fi fi c = h Gamma [ g 1 ; g n 2 P a 1 hh i Gamma i [ b i i n i=1 c P a 2 0 = Omega n Omega i=1 ( i Omega ff A (g i = h i ) 9 = Likewise concrete unfolding, unf A is proved to be associative, additive and continuous (see [14]) The abstract semantics F A : AInt AInt is defined for a program module P as F A (ff(P) lfp(T A ff(P) where T A ff(P) AInt AInt is defined by T A ff(P) I a ) unf A (ff(P) I a t ff( Phi P ) By Omega correctness, F A is correct with respect to F ( 6, 14] 4 ....

.... (see [14] The abstract semantics F A : AInt AInt is defined for a program module P as F A (ff(P) lfp(T A ff(P) where T A ff(P) AInt AInt is defined by T A ff(P) I a ) unf A (ff(P) I a t ff( Phi P ) By Omega correctness, F A is correct with respect to F ([6, 14]) 4 Abductive Analysis 4.1 Abduction as composition inverse Given a program module P , our goal is to find a specification (property) for open(P) once a specification of P is given 3 . A formal account of this process can be given in terms of the well known Dijkstra s weakest precondition ....

[Article contains additional citation context not shown here]

R. Giacobazzi. Semantic Aspects of Logic Program Analysis. PhD thesis, Dipartimento di Informatica, Universit`a di Pisa, 1993. TD -- 18/93.

.... program analysis has been firstly addressed in [8] by introducing a framework which is based on the compositional semantics F , and which formalizes the analysis in terms of the standard theory of abstract interpretation ( 12] In this section we briefly introduce some notions and results from [8, 18]. For the sake of completeness, we include in the appendix the proofs of those results which are relevant for abductive analysis. We follow [8] by assuming that (Int ; ff; AInt ; fl) is a Galois insertion, and that the abstract semantics F A : AInt AInt safely mimics F , i.e. for each I 2 Int ....

....to contain at most one occurrence of each (open) predicate symbol. In this case, since Pi is usually finite, the domain of abstract interpretations AInt results a finite height lattice. The abstracted compositional semantics is denoted F A . This semantics is compositional correct (see [8, 18]) therefore, by Theorem 4.13, it can be correctly used in abstract abduction. The abstraction is specific for some abstract domain for analysis. We will see the case for ground dependencies in Example 5.3 below. The approach in [17] is instead oriented to provide a compositional complete ....

[Article contains additional citation context not shown here]

R. Giacobazzi. Semantic Aspects of Logic Program Analysis. PhD thesis, Dipartimento di Informatica, Universit`a di Pisa, 1993. TD -- 18/93. URL http://www.di.unipi.it/¸giaco/papers.html.

....Keywords: Logic programs, abstract interpretation, procedure calls. 1 Introduction In this paper we consider a new application in the area of abstract interpretation based on the s semantics approach [12, 3] Several abstract interpretation frameworks based on this approach have been defined [15], including those based [2, 6] on the original s semantics (modeling computed answer substitutions) 11] Starting from the simplified version of an existing concrete semantics [14] here we propose an abstract semantics to analyse, in a goal independent way, properties of call patterns. Call ....

R. Giacobazzi. Semantic Aspects of Logic Program Analysis. PhD thesis, Dipartimento di Informatica, Universit`a di Pisa, 1992.

Online articles have much greater impact   More about CiteSeer.IST   Add search form to your site   Submit documents   Feedback  

CiteSeer.IST - Copyright Penn State and NEC