In doing a search for a string typically a variable name the find feature of the software lists the results and whilst giving the line number in the file does not list the subroutine name. Dec 28, 2009 fortran coverage analysis tool fcat is used to find out coldspot and hotspot in fortran codes. Run during the link step of an application build, the entire application, including linked libraries, is available for interprocedural analysis. The intel fortran compiler is available as part of the intel parallel studio xe 2016 suite, which focuses on development of parallelism models in application software.
If interprocedural alignment analysis enabled under qip or qipo has failed to derive any useful conclusion on the alignment of the memory regions associated with the formal pointer argument x, the compiler resorts to dynamic loop peeling to enforce an aligned access pattern in the iloop. Practice and experience on deepdyve, the largest online rental service for scholarly research with thousands of academic publications available at your fingertips. Ipo differs from other compiler optimization because it analyzes. Improve fortran code quality with static analysis intel parallel studio xe evaluation guide introduction this document is an introductory tutorial describing the static analysis feature of the intel parallel studio xe. Interprocedural optimization ipo is a collection of compiler techniques used in computer. Read interprocedural data flow based optimizations for distributed memory compilation, software. Interprocedural analysis ipa enables the compiler to optimize across different files wholeprogram analysis, and it can result in significant performance improvements. Cache tiling concurrent call support inline concurrent code segments vector sseavx code generation software prefetching parallel debug engine 64bit and 32bit targets debug fortran. The flag to enable interprocedural optimizations for a single file is ip, the flag to enable interprocedural optimization across all files in the program is ipo. The compiler may apply the following optimizations. In this effort, a special emphasis is placed on dataparallel programming and scalable parallelism.
Interprocedural analysis an overview sciencedirect topics. This might be a useful feature to include in future versions of the software. The impact of interprocedural analysis and optimization on. Fortran compiler, an evaluation on spec cpu2000 floatingpoint benchmark. Interprocedural dependency ananlyser ida is an interactive tool that provides interprocedural information about fortran programs.
This has resulted in the development of algorithms for interprocedural analysis of the side effects of a subroutine, which summarize the body of a subroutine, producing approximate information to improve optimization. An aggressive interprocedural constant propagation algorithm, such as the one implemented in this optimizer, can find many constants to propagate into procedures in scientific fortran applications. Implicit aliasing caused by reference parameter passing can be uncovered in a program with multiple. The compiler can perform highquality interprocedural analysis, dataflow analysis, data dependence analysis, and array region analysis. Computers and internet computer science research data processing electronic data processing programming languages. The gnu gcc compiler has function inlining, which is turned on by default at o3, and can be turned on manually via passing the switch finlinefunctions at compile time. But research on the analysis of fortran programs is still go. It can sometimes make sense to perform interprocedural.
It performs interprocedural analysis to resolve questions of naming and side effects in order to improve the effectiveness of subsequent procedural optimization. Both of these systems implement recompilation analysis using techniques described in this paper. Interprocedural optimization is a collection of compiler techniques used in computer programming to improve performance in programs containing many frequently used functions of small or medium length. Computers and internet algorithms analysis compilers software. Computers and internet algorithms analysis compilers software compiling electronic computers parallel programming computer science methods. Addresstaken analysis array dimension padding alias analysis automatic array transposition automatic memory pool. This report explains the goals and limitations of alias analysis for conventional procedural languages with reference parameters, shows in detail the actual design and implementation of ipa, and provides algorithmic and speed improvements over the best previously known aliasing algorithms. We have implemented a tool that analyzes fortran 90 application programs and performs an interprocedural pointer analysis. The impact of interprocedural analysis and optimization on the design of a software development environment article pdf available in acm sigplan notices 207. If there is a call to another routine that occurs within a loop, ipo analysis may determine that it is best to inline that. Keywords software maintenance of legacy code program understanding program specialization interprocedural analysis inference rules natural semantics formal specification fortran. We construct an abstract data type adt module that hides the implementation details of the queue and exports only the name of the type and a set of operations to insert a data.
This report explains the goals and limitations of alias analysis for. The following syntax box shows the complete f901 command syntax. Portland group recommends that you use the pgf90 for both fortran 90 and fortran 77 codes to gain additional code speed up. At the heart of parascope are its facilities for interprocedural analysis and optimization of fortran programs and an intelligent editor that provides programmers with information about how memory is shared among loop iterations, helping them make decisions about how parallelism can best be exploited. In the rest of the paper, we will present the frequency model, the estimation methods, and the interprocedural analysis. Interprocedural slicing using dependence graphs acm. This paper presents techniques for efficient interprocedural array dataflow analysis and documents experimental results of its implementation in a research parallelizing compiler. Whole program mode expands the scope of optimization to an entire program unit, which can be an executable or a shared object.
Abstract in this paper we examine the role played by the interprocedural analysis of array accesses in the automatic parallelization of fortran programs. Both of these systems implement recompilation analysis. Forcheck detects more anomalies in your program than most compilers do. Interprocedural analyses of fortran programs sciencedirect. For scalar objects and for full arrays, the ipa processor described here finds all alias relations. A schema for interprocedural modification sideeffect. Interprocedural constant propagation acm sigplan notices. You can specify interprocedural analysis on the compilation step only or on both compilation and link steps in whole program mode. Data parallel languages like high performance fortran hpf are emerging as the architecture independent mode of programming distributed memory parallel machines. This has resulted in the development of algorithms for interprocedural analysis of the side effects of a subroutine, which summarize the body of a subroutine, producing approximate. The compiler may be able to perform additional optimizations if it is able to optimize across source line boundaries. Interprocedural optimization ipo is an automatic, multistep process that allows the compiler to analyze your code to determine where you.
Interprocedural analysis ipa can analyze and optimize your application as a whole, rather than on a filebyfile basis. For complete details about each option, see the f901 man page. In this paper, we present the interprocedural optimizations required for compiling applications that have irregular data access patterns, when coded in such data parallel languages. Box 1892 rice university houston, texas 77251 1 introduction this paper discusses a method for interprocedural data flow analysis which is powerful enough to express flow. Introduction the imsl library contains over one thousand fortran subroutines and functions. These routines provide easy access to high quality implementations of numerical methods in mathematics and statistics. These may include, but are not limited to, function inlining. Interprocedural analysis and optimization rice computer science. Performing interprocedural analysis of memory references, which allows registerization of more. It also performs a number of true interprocedural optimizations. Recompile the program using the ipo option to enable interprocedural. Interprocedural analysis and optimizations are common in modern commercial compilers from hp, ibm, sgi, intel, microsoft, and sun microsystems. For example, consider the small c program shown in figure 9. Citeseerx automated recognition of parallel algorithms in.
To use these compilers, you should be aware of the role of highlevel languages, such as fortran, c, and c. Algorithms exist for compiling fortran d for mimd multipleinstruction multipledata distributedmemory machines, but they are significantly restricted in the presence of procedure calls. The difficulty of that analysis is due to the lack of well defined interprocedural mechanisms and the complexity of visibility rules in fortran. Pdf data dependence analysis for fortran programs in the. A central goal of the r n project at rice university is to construct a prototype software development environment that is designed to build whole programs, rather than just individual modules.
Pgi visual fortran users guide pgi compilers and tools. It can conduct highquality interprocedural analysis, dataflow analysis, data dependence analysis, and array region analysis. This chapter provides an overview to the options for the f901 command. In this paper we extend our previous work to interprocedural analysis taking into account dynamic realignment. Implicit aliasing caused by reference parameter passing can be uncovered in a program with multiple compilation units by interprocedural analysis. Efficient interprocedural array dataflow analysis for automatic program parallelization article in ieee transactions on software engineering 263. Most of the required inter procedural information is developed by solving data flow analysis problems on the programs call graph. Interprocedural analyses ipa are becoming more and more common in commercial compilers.
Since the call graph of a program is likely to be large, it is impor. An empirical study of precise interprocedural array analysis. At the heart of parascope are its facilities for interprocedural analysis and optimization of fortran programs and an intelligent editor that provides programmers with information about how memory is. It provides a brief description of the goals of the product feature and walks through an endtoend example showing. It performs a static analysis of a fortran program or separate fortran program units. Using auto vectorization overview fortran the intel compiler has an autovectorizer that detects operations in the application that can be done in parallel and converts sequential operations to parallel operations by using the single instruction multiple data simd instruction set. The impact of interprocedural analysis and optimization in. Interprocedural data flow based optimizations for distributed. The program summary graph and flowsensitive interprocedural data flow analysis david callahan department of computer science p.
The program summary graph and flowsensitive interprocedural. It summarizes the interprocedural con trol flow in a way that generalizes the more traditional call graph, but is more compact than the program super graph described by myers 22. Interprocedural optimizations, including selective inlining, within a single source file. In the pgi implementation, the compiler saves a both a brief program summary and complete recompile information in the generated object le. The impact of interprocedural analysis and optimization in the r. Partial evaluation is an optimization technique traditionally used in compilation. Sigplansigsoft workshop on program analysis for software tools and engineering, toulouse, france, sept. This paper presents a dynamic semantics of fortran. Detailed statistics derived from compiling a large set of real scientific applications characterize both the opportunities for interprocedural. Forcheck is the oldest and most comprehensive fortran analysis tool on the market. Data dependence analysis for fortran programs in the impact compiler.
Ibm xl fortran for aix maximizes application performance on ibm power systems. This compiler also contains all of the components of the convex optimizing fortran and c compilers. We report our experiences with the implementation of interprocedural alias analysis ipa for fortran. How to enhance the efficiency of this analysis to a practical level remains an issue largely untouched to date. The authors present interprocedural analysis, optimization, and code generation algorithms for fortran. Recompile the program using the ipo option to enable interprocedural optimization. Development has ceased, although other projects can use the projects source. The authors discuss the use of interprocedural dataflow information in analysis that leads to reducing the recompilation needed when a procedure in a large program is changed. Hi, in my application i have some files that contain many subroutines.
We presented an overview of an automatic alignment analysis tool elsewhere, which is able to automatically generate alignment proposals for the arrays accessed in a procedure and thus simplifies the data distribution problem. For languages like fortran, aliases arise only due to. It can sometimes make sense to perform interprocedural analyses within an intermediate level, such as a library or a java package. This manual is intended for scientists and engineers using the pgi compilers. Specifying and automatically generating a specialization. Interprocedural optimization refers to program transformations that involve. Interprocedural optimization ipo intel fortran compiler 19. In this paper we examine the role played by the interprocedural analysis of array accesses in the automatic parallelization of fortran programs. Amd64 and intel 64 crosstarget optimizations interprocedural analysis.
The notion of a program slice, originally introduced by mark weiser, is useful in program debugging, automatic parallelization, and program integration. Improving performance with interprocedural optimization. Fortran com server interface design considerations windows advanced com server topics windows deploying the com server on another system windows using the intel fortran module wizard com client windows understanding com and automation objects windows the role of the module wizard windows. A schema for interprocedural modification sideeffect analysis with pointer aliasing. In a compiling system that attempts to improve code for a whole program by optimizing across procedures, the compiler can generate better code for a specific procedure if it knows which variables w. One of the primary goals of the irn programming environment project is to mount a concerted attack on the problems of performing interprocedural analysis and optimization in a compiler. A slice of a program is taken with respect to a program point p and a variable x.
Interprocedural static analysis of sequencing constraints. White paper optimizing division applications with intel. The isml fortran library tutorial 3 the department of statistics and data sciences, the university of texas at austin section 1. In a compiling system that attempts to improve code for a whole program by optimizing across procedures, the compiler can generate better code for a specific procedure if it knows which variables. Dec 16, 2019 interprocedural optimization ipo is an automatic, multistep process that allows the compiler to analyze your code to determine where you can benefit from specific optimizations.
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