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28
Efficiently computing static single assignment form and the control dependence graph
 ACM TRANSACTIONS ON PROGRAMMING LANGUAGES AND SYSTEMS
, 1991
"... In optimizing compilers, data structure choices directly influence the power and efficiency of practical program optimization. A poor choice of data structure can inhibit optimization or slow compilation to the point that advanced optimization features become undesirable. Recently, static single ass ..."
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Cited by 839 (7 self)
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In optimizing compilers, data structure choices directly influence the power and efficiency of practical program optimization. A poor choice of data structure can inhibit optimization or slow compilation to the point that advanced optimization features become undesirable. Recently, static single assignment form and the control dependence graph have been proposed to represent data flow and control flow propertiee of programs. Each of these previously unrelated techniques lends efficiency and power to a useful class of program optimization. Although both of these structures are attractive, the difficulty of their construction and their potential size have discouraged their use. We present new algorithms that efficiently compute these data structures for arbitrary control flow graphs. The algorithms use dominance frontiers, a new concept that may have other applications. We also give analytical and experimental evidence that all of these data structures are usually linear in the size of the original program. This paper thus presents strong evidence that these structures can be of practical use in optimization.
Efficient ContextSensitive Pointer Analysis for C Programs
, 1995
"... This paper proposes an efficient technique for contextsensitive pointer analysis that is applicable to real C programs. For efficiency, we summarize the effects of procedures using partial transfer functions. A partial transfer function (PTF) describes the behavior of a procedure assuming that certa ..."
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Cited by 396 (9 self)
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This paper proposes an efficient technique for contextsensitive pointer analysis that is applicable to real C programs. For efficiency, we summarize the effects of procedures using partial transfer functions. A partial transfer function (PTF) describes the behavior of a procedure assuming that certain alias relationships hold when it is called. We can reuse a PTF in many calling contexts as long as the aliases among the inputs to the procedure are the same. Our empirical results demonstrate that this technique is successfula single PTF per procedure is usually sufficient to obtain completely contextsensitive results. Because many C programs use features such as type casts and pointer arithmetic to circumvent the highlevel type system, our algorithm is based on a lowlevel representation of memory locations that safely handles all the features of C. We have implemented our algorithm in the SUIF compiler system and we show that it runs efficiently for a set of C benchmarks. 1 Introd...
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 ..."
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Cited by 78 (9 self)
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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...
DependenceBased Program Analysis
 In Proceedings of the SIGPLAN '93 Conference on Programming Language Design and Implementation
, 1993
"... Program analysis and optimization can be speeded up through the use of the dependence flow graph (DFG), a representation of program dependences which generalizes defuse chains and static single assignment (SSA) form. In this paper, we give a simple graphtheoretic description of the DFG and show ho ..."
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Cited by 60 (6 self)
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Program analysis and optimization can be speeded up through the use of the dependence flow graph (DFG), a representation of program dependences which generalizes defuse chains and static single assignment (SSA) form. In this paper, we give a simple graphtheoretic description of the DFG and show how the DFG for a program can be constructed in O(EV ) time. We then show how forward and backward dataflow analyses can be performed efficiently on the DFG, using constant propagation and elimination of partial redundancies as examples. These analyses can be framed as solutions of dataflow equations in the DFG. Our construction algorithm is of independent interest because it can be used to construct a program's control dependence graph in O(E) time and its SSA representation in O(EV ) time, which are improvements over existing algorithms. 1 Introduction Anumber of recent papers have focused attention on the problem of speeding up program optimization [FOW87, BMO90, CCF91, PBJ + 91, CFR +...
Value Numbering
, 1997
"... This paper compares hashbased approaches derived from the classic local algorithm ..."
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Cited by 54 (11 self)
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This paper compares hashbased approaches derived from the classic local algorithm
Interprocedural Symbolic Analysis
, 1994
"... Compiling for efficient execution on advanced computer architectures requires extensive program analysis and transformation. Most compilers limit their analysis to simple phenomena within single procedures, limiting effective optimization of modular codes and making the programmer's job harder. We p ..."
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Cited by 49 (1 self)
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Compiling for efficient execution on advanced computer architectures requires extensive program analysis and transformation. Most compilers limit their analysis to simple phenomena within single procedures, limiting effective optimization of modular codes and making the programmer's job harder. We present methods for analyzing array side effects and for comparing nonconstant values computed in the same and different procedures. Regular sections, described by rectangular bounds and stride, prove as effective in describing array side effects in Linpack as more complicated summary techniques. On a set of six programs, regular section analysis of array side effects gives 0 to 39 percent reductions in array dependences at call sites, with 10 to 25 percent increases in analysis time. Symbolic analysis is essential to data dependence testing, array section analysis, and other highlevel program manipulations. We give methods for building symb...
Symbolic Program Analysis and Optimization for Parallelizing Compilers
 Presented at the 5th Annual Workshop on Languages and Compilers for Parallel Computing
, 1992
"... A program flow analysis framework is proposed for parallelizing compilers. Within this framework, symbolic analysis is used as an abstract interpretation technique to solve many of the flow analysis problems in a unified way. Some of these problems are constant propagation, global forward substituti ..."
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Cited by 35 (3 self)
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A program flow analysis framework is proposed for parallelizing compilers. Within this framework, symbolic analysis is used as an abstract interpretation technique to solve many of the flow analysis problems in a unified way. Some of these problems are constant propagation, global forward substitution, detection of loop invariant computations, and induction variable substitution. The solution space of the above problems is much larger than that handled by existing compiler technology. It covers many of the cases in benchmark codes that other parallelizing compilers can not handle. Employing finite difference methods, the symbolic analyzer derives a functional representation of programs, which is used in dependence analysis. A systematic method for generalized strength reduction based on this representation is also presented. This results in an effective scheme for exploitation of parallelism and optimization of the code. Symbolic analysis also serves as a basis for other code generatio...
DominatorPath Scheduling  A Global Scheduling Method
 in Proceedings of the 25th International Symposium on Microarchitecture (MICRO25
, 1992
"... Dominatorpath scheduling performs global instruction scheduling of paths in the dominator tree. Unlike other global scheduling methods, dominatorpath scheduling does not require copies of operations to preserve program semantics. In a limited test suite for a typical superscalar architecture, domi ..."
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Cited by 23 (3 self)
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Dominatorpath scheduling performs global instruction scheduling of paths in the dominator tree. Unlike other global scheduling methods, dominatorpath scheduling does not require copies of operations to preserve program semantics. In a limited test suite for a typical superscalar architecture, dominatorpath scheduling produces schedules requiring 8.3% fewer cycles than local scheduling alone. 1 Introduction Architectures exhibiting instructionlevel parallelism (ILP), such as superscalar and superpipelined machines, are currently popular. To best exploit instructionlevel parallelism in these machines, an instruction scheduling phase is required during compilation. Instruction scheduling is typically classified as local if it considers code only within a basic block and global if it schedules multiple basic blocks at once. Local scheduling methods are well known (see [Bea91] for one summary.) Local instruction scheduling's largest impediment is its inability to consider context from...
Reducing the Cost of Data Flow Analysis By Congruence Partitioning
 In International Conference on Compiler Construction
, 1994
"... . Data flow analysis expresses the solution of an information gathering problem as the fixed point of a system of monotone equations. This paper presents a technique to improve the performance of data flow analysis by systematically reducing the size of the equation system in any monotone data flow ..."
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Cited by 20 (1 self)
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. Data flow analysis expresses the solution of an information gathering problem as the fixed point of a system of monotone equations. This paper presents a technique to improve the performance of data flow analysis by systematically reducing the size of the equation system in any monotone data flow problem. Reductions result from partitioning the equations in the system according to congruence relations. We present a fast O(n log n) partitioning algorithm, where n is the size of the program, that exploits known algebraic properties in equation systems. From the resulting partition a reduced equation system is constructed that is minimized with respect to the computed congruence relation while still providing the data flow solution at all program points. 1 Introduction Along with the growing importance of static data flow analysis in current optimizing and parallelizing compilers comes an increased concern about the high time and space requirements of solving data flow problems. Experi...
Static Single Information Form
 Master's thesis, Massachussets Institute of Technology
, 1999
"... This paper presents a new intermediate format called Static Single Information (SSI) form. SSI form generalizes the traditional concept of a variable de nition to include all information de nition points, or points where the analysis may obtain information about the value in a variable. Informatio ..."
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Cited by 20 (0 self)
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This paper presents a new intermediate format called Static Single Information (SSI) form. SSI form generalizes the traditional concept of a variable de nition to include all information de nition points, or points where the analysis may obtain information about the value in a variable. Information de nition points include conditional branches as well as assignments. Because SSI form provides a new name for each variable at each information de nition point, it provides excellent support for both predicated analyses, which exploit information gained from conditionals, and backwards dataow analyses.