Results 1  10
of
66
Interprocedural Dataflow Analysis via Graph Reachability
, 1994
"... This paper shows howalarge class of interprocedural dataflowanalysis problems can be solved precisely in polynomial time. The only restrictions are that the set of dataflow facts is a finite set, and that the dataflow functions distribute overthe confluence operator (either union or intersection). ..."
Abstract

Cited by 373 (33 self)
 Add to MetaCart
This paper shows howalarge class of interprocedural dataflowanalysis problems can be solved precisely in polynomial time. The only restrictions are that the set of dataflow facts is a finite set, and that the dataflow functions distribute overthe confluence operator (either union or intersection). This class of problems includesbut is not limited tothe classical separable problems (also known as "gen/kill" or "bitvector" problems)e.g.,reaching definitions, available expressions, and live variables. In addition, the class of problems that our techniques handle includes manynonseparable problems, including trulylive variables, copyconstant propagation, and possiblyuninitialized variables. Anovelaspect of our approach is that an interprocedural dataflowanalysis problem is transformed into a special kind of graphreachability problem (reachability along interprocedurally realizable paths). The paper presents three polynomialtime algorithms for the realizablepath reachability problem: an exhaustive version, a second exhaustive version that may be more appropriate in the incremental and/or interactive context, and a demand version. The first and third of these algorithms are asymptotically faster than the best previously known realizablepath reachability algorithm. An additional benefit of our techniques is that theylead to improved algorithms for twoother kinds of interprocedural analysis problems: interprocedural flowsensitive sideeffect problems (as studied by Callahan) and interprocedural program slicing (as studied by Horwitz, Reps, and Binkley).
Optimal Code Motion: Theory and Practice
, 1993
"... An implementation oriented algorithm for lazy code motion is presented that minimizes the number of computations in programs while suppressing any unnecessary code motion in order to avoid superfluous register pressure. In particular, this variant of the original algorithm for lazy code motion works ..."
Abstract

Cited by 112 (18 self)
 Add to MetaCart
An implementation oriented algorithm for lazy code motion is presented that minimizes the number of computations in programs while suppressing any unnecessary code motion in order to avoid superfluous register pressure. In particular, this variant of the original algorithm for lazy code motion works on flowgraphs whose nodes are basic blocks rather than single statements, as this format is standard in optimizing compilers. The theoretical foundations of the modified algorithm are given in the first part, where trefined flowgraphs are introduced for simplifying the treatment of flowgraphs whose nodes are basic blocks. The second part presents the `basic block' algorithm in standard notation, and gives directions for its implementation in standard compiler environments. Keywords Elimination of partial redundancies, code motion, data flow analysis (bitvector, unidirectional, bidirectional), nondeterministic flowgraphs, trefined flow graphs, critical edges, lifetimes of registers, com...
Weighted pushdown systems and their application to interprocedural dataflow analysis
 Sci. of Comp. Prog
, 2003
"... Abstract. Recently, pushdown systems (PDSs) have been extended to weighted PDSs, in which each transition is labeled with a value, and the goal is to determine the meetoverallpaths value (for paths that meet a certain criterion). This paper shows how weighted PDSs yield new algorithms for certain ..."
Abstract

Cited by 106 (35 self)
 Add to MetaCart
Abstract. Recently, pushdown systems (PDSs) have been extended to weighted PDSs, in which each transition is labeled with a value, and the goal is to determine the meetoverallpaths value (for paths that meet a certain criterion). This paper shows how weighted PDSs yield new algorithms for certain classes of interprocedural dataflowanalysis problems. 1
Demanddriven Computation of Interprocedural Data Flow
, 1995
"... This paper presents a general framework for deriving demanddriven algorithms for interprocedural data flow analysis of imperative programs. The goal of demanddriven analysis is to reduce the time and/or space overhead of conventional exhaustive analysis by avoiding the collection of information tha ..."
Abstract

Cited by 78 (9 self)
 Add to MetaCart
This paper presents a general framework for deriving demanddriven algorithms for interprocedural data flow analysis of imperative programs. The goal of demanddriven analysis is to reduce the time and/or space overhead of conventional exhaustive analysis by avoiding the collection of information that is not needed. In our framework, a demand for data flow information is modeled as a set of data flow queries. The derived demanddriven algorithms find responses to these queries through a partial reversal of the respective data flow analysis. Depending on whether minimizing time or space is of primary concern, result caching may be incorporated in the derived algorithm. Our framework is applicable to interprocedural data flow problems with a finite domain set. If the problem's flow functions are distributive, the derived demand algorithms provide as precise information as the corresponding exhaustive analysis. For problems with monotone but nondistributive flow functions the provided dat...
Precise Interprocedural Analysis through Linear Algebra
, 2004
"... We apply linear algebra techniques to precise interprocedural dataflow analysis. Specifically, we describe analyses that determine for each program point identities that are valid among the program variables whenever control reaches that program point. Our analyses fully interpret assignment stateme ..."
Abstract

Cited by 62 (10 self)
 Add to MetaCart
We apply linear algebra techniques to precise interprocedural dataflow analysis. Specifically, we describe analyses that determine for each program point identities that are valid among the program variables whenever control reaches that program point. Our analyses fully interpret assignment statements with affine expressions on the right hand side while considering other assignments as nondeterministic and ignoring conditions at branches. Under this abstraction, the analysis computes the set of all affine relations and, more generally, all polynomial relations of bounded degree precisely. The running time of our algorithms is linear in the program size and polynomial in the number of occurring variables. We also show how to deal with affine preconditions and local variables and indicate how to handle parameters and return values of procedures.
A Practical Framework for DemandDriven Interprocedural Data Flow Analysis
 ACM Transactions on Programming Languages and Systems
, 1998
"... this article, we present a general framework for developing demanddriven interprocedural data flow analyzers and report our experience in evaluating the performance of this approach. A demand for data flow information is modeled as a set of queries. The framework includes a generic demanddriven al ..."
Abstract

Cited by 58 (10 self)
 Add to MetaCart
this article, we present a general framework for developing demanddriven interprocedural data flow analyzers and report our experience in evaluating the performance of this approach. A demand for data flow information is modeled as a set of queries. The framework includes a generic demanddriven algorithm that determines the response to a query by iteratively applying a system of query propagation rules. The propagation rules yield precise responses for the class of distributive finite data flow problems. We also describe a twophase framework variation to accurately handle nondistributive problems. A performance evaluation of our demanddriven approach is presented for two data flow problems, namely, reachingdefinitions and copy constant propagation. Our experiments show that demanddriven analysis performs well in practice, reducing both time and space requirements when compared with exhaustive analysis.
Reducing Concurrent Analysis Under a Context Bound to Sequential Analysis
"... Abstract. This paper addresses the analysis of concurrent programs with shared memory. Such an analysis is undecidable in the presence of multiple procedures. One approach used in recent work obtains decidability by providing only a partial guarantee of correctness: the approach bounds the number of ..."
Abstract

Cited by 49 (11 self)
 Add to MetaCart
Abstract. This paper addresses the analysis of concurrent programs with shared memory. Such an analysis is undecidable in the presence of multiple procedures. One approach used in recent work obtains decidability by providing only a partial guarantee of correctness: the approach bounds the number of context switches allowed in the concurrent program, and aims to prove safety, or find bugs, under the given bound. In this paper, we show how to obtain simple and efficient algorithms for the analysis of concurrent programs with a context bound. We give a general reduction from a concurrent program P, and a given context bound K, to a slightly larger sequential program P K s such that the analysis of P K s can be used to prove properties about P. The reduction introduces symbolic constants and assume statements in P K s. Thus, any sequential analysis that can deal with these two additions can be extended to handle concurrent programs as well, under the context bound. We give instances of the reduction for common program models used in model checking, such as Boolean programs, pushdown systems (PDSs), and symbolic PDSs. 1
Generation of efficient interprocedural analyzers with PAG
 In Proceedings of the Second INternational Symposium on Static Analysis
, 1995
"... . To produce high quality code, modern compilers use global optimization algorithms based on abstract interpretation. These algorithms are rather complex; their implementation is therefore a nontrivial task and errorprone. However, since they are based on a common theory, they have large similar ..."
Abstract

Cited by 48 (7 self)
 Add to MetaCart
. To produce high quality code, modern compilers use global optimization algorithms based on abstract interpretation. These algorithms are rather complex; their implementation is therefore a nontrivial task and errorprone. However, since they are based on a common theory, they have large similar parts. We conclude that analyzer writing better should be replaced with analyzer generation. We present the tool PAG that has a high level functional input language to specify data flow analyses. It offers the specification of even recursive data structures and is therefore not limited to bit vector problems. PAG generates efficient analyzers which can be easily integrated in existing compilers. The analyzers are interprocedural, they can handle recursive procedures with local variables and higher order functions. PAG has successfully been tested by generating several analyzers (e.g. alias analysis, constant propagation) for an industrial quality ANSIC and Fortran90 compiler. Keywords: d...
Parallelism for Free: Efficient and Optimal Bitvector Analyses for Parallel Programs
, 1994
"... In this paper we show how to construct optimal bitvector analysis algorithms for parallel programs with shared memory that are as efficient as their purely sequential counterparts, and which can easily be implemented. Whereas the complexity result is rather obvious, our optimality result is a conseq ..."
Abstract

Cited by 46 (3 self)
 Add to MetaCart
In this paper we show how to construct optimal bitvector analysis algorithms for parallel programs with shared memory that are as efficient as their purely sequential counterparts, and which can easily be implemented. Whereas the complexity result is rather obvious, our optimality result is a consequence of a new Kam/Ullmanstyle Coincidence Theorem. Thus, the important merits of sequential bitvector analyses survive the introduction of parallel statements. Keywords Parallelism, interleaving semantics, synchronization, program optimization, data flow analysis, bitvector problems, definitionuse chains, partial redundancy elimination, partial dead code elimination. Contents 1 Motivation 1 2 Sequential Programs 2 2.1 Representation : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 2 2.2 Data Flow Analysis : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : : 2 2.2.1 The MOPSolution of a DFA : : : : : : : : : : : : : : : : : : : : : : 2 2.2.2 The MFPSolution o...