The Complexity of Copy Constant Detection in Parallel Programs
نویسنده
چکیده
Despite of the well-known state-explosion problem, certain simple but important data-flow analysis problems known as gen/kill problems can be solved efficiently and completely for parallel programs with a shared state [7, 6, 2, 3, 13]. This paper shows that, in all probability, these surprising results cannot be generalized to significantly larger classes of data-flow analysis problems. More specifically, we study the complexity of detecting copy constants in parallel programs, a problem that may be seen as representing the next level of difficulty of data-flow problems beyond gen/kill problems. We show that already the intraprocedural problem for loop-free parallel programs is co-NP-complete and that the interprocedural problem is even PSPACE-hard.
منابع مشابه
Parallel Generation of t-ary Trees
A parallel algorithm for generating t-ary tree sequences in reverse B-order is presented. The algorithm generates t-ary trees by 0-1 sequences, and each 0-1 sequences is generated in constant average time O(1). The algorithm is executed on a CREW SM SIMD model, and is adaptive and cost-optimal. Prior to the discussion of the parallel algorithm a new sequential generation with O(1) average time ...
متن کاملA Parallel Genetic Algorithm Based Method for Feature Subset Selection in Intrusion Detection Systems
Intrusion detection systems are designed to provide security in computer networks, so that if the attacker crosses other security devices, they can detect and prevent the attack process. One of the most essential challenges in designing these systems is the so called curse of dimensionality. Therefore, in order to obtain satisfactory performance in these systems we have to take advantage of app...
متن کاملA Parallel Genetic Algorithm Based Method for Feature Subset Selection in Intrusion Detection Systems
Intrusion detection systems are designed to provide security in computer networks, so that if the attacker crosses other security devices, they can detect and prevent the attack process. One of the most essential challenges in designing these systems is the so called curse of dimensionality. Therefore, in order to obtain satisfactory performance in these systems we have to take advantage of app...
متن کاملPerformance evaluation of block-based copy- move image forgery detection algorithms
Copy-move forgery is a particular type of distortion where a part or portions of one image is/are copied to other parts of the same image. This type of manipulation is done to hide a particular part of the image or to copy one or more objects into the same image. There are several methods for detecting copy-move forgery, including block-based and key point-based methods. In this paper, a method...
متن کاملDetection of Copy-Move Forgery in Digital Images Using Scale Invariant Feature Transform Algorithm and the Spearman Relationship
Increased popularity of digital media and image editing software has led to the spread of multimedia content forgery for various purposes. Undoubtedly, law and forensic medicine experts require trustworthy and non-forged images to enforce rights. Copy-move forgery is the most common type of manipulation of digital images. Copy-move forgery is used to hide an area of the image or to repeat a por...
متن کامل