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Def-use Chains
Within computer science, a Use-Definition Chain (''UD Chain'') is a data structure that consists of a use, U, of a Variable (programming), variable, and all the definitions, D, of that variable that can reach that use without any other intervening definitions. A UD Chain generally means the Assignment (computer science), assignment of some value to a variable. A counterpart of a ''UD Chain'' is a Definition-Use Chain (''DU Chain''), which consists of a definition, D, of a variable and all the uses, U, reachable from that definition without any other intervening definitions. Both UD and DU chains are created by using a form of static code analysis known as data flow analysis. Knowing the use-def and def-use chains for a program or subprogram is a prerequisite for many compiler optimizations, including constant propagation and common subexpression elimination. Purpose Making the use-define or define-use chains is a step in liveness analysis, so that logical representations of all th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Computer Science
Computer science is the study of computation, automation, and information. Computer science spans theoretical disciplines (such as algorithms, theory of computation, information theory, and automation) to Applied science, practical disciplines (including the design and implementation of Computer architecture, hardware and Computer programming, software). Computer science is generally considered an area of research, academic research and distinct from computer programming. Algorithms and data structures are central to computer science. The theory of computation concerns abstract models of computation and general classes of computational problem, problems that can be solved using them. The fields of cryptography and computer security involve studying the means for secure communication and for preventing Vulnerability (computing), security vulnerabilities. Computer graphics (computer science), Computer graphics and computational geometry address the generation of images. Progr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
