On the Complexity of Constant Propagation
نویسندگان
چکیده
Constant propagation (CP) is one of the most widely used optimizations in practice (cf. [9]). Intuitively, it addresses the problem of statically detecting whether an expression always evaluates to a unique constant at run-time. Unfortunately, as proved by different authors [4, 16], CP is in general undecidable even if the interpretation of branches is completely ignored. On the other hand, it is certainly decidable in more restricted settings, like on loop-free programs (cf. [7]). In this paper, we explore the complexity of CP for a three-dimensional taxonomy. We present an almost complete complexity classification, leaving only two upper bounds open.
منابع مشابه
A New Method for Calculating Propagation Modes of a One Dimensional Photonic Crystal (RESEARCH NOTE)
Photonic band-gap (PBG) crystals offer new dimensions of freedom in controlling propagation of electromagnetic waves. The existence of stop-bands in the transmission characteristic of these crystals makes them a suitable element for the realization of many useful microwave and optical subsystems. In this paper, we calculate the propagation constant of a one-dimensional (1-D) photonic crystal by...
متن کاملParallel implementation of underwater acoustic wave propagation using beamtracing method on graphical processing unit
The mathematical modeling of the acoustic wave propagation in seawater is the basis for realizing goals such as, underwater communication, seabed mapping, advanced fishing, oil and gas exploration, marine meteorology, positioning and explore the unknown targets within the water. However, due to the existence of various physical phenomena in the water environment and the various conditions gover...
متن کاملInvestigating the Properties of an Optical Waveguide Based on Photonic Crystal with Point Defect and Lattice Constant Perturbation
In this paper, a photonic crystal waveguide with point defects and lattice constant perturbations of +5%, -5% are being investigated. Firstly waveguide structures with constant and specific parameters are being studied and photonic band gap diagrams for TE/TM modes are depicted; then pulse propagation in the frequencies available in the band gap are shown. After that, effects of parameters like...
متن کاملOn the use of back propagation and radial basis function neural networks in surface roughness prediction
Various artificial neural networks types are examined and compared for the prediction of surface roughness in manufacturing technology. The aim of the study is to evaluate different kinds of neural networks and observe their performance and applicability on the same problem. More specifically, feed-forward artificial neural networks are trained with three different back propagation algorithms, ...
متن کاملThe Effect of Water Surface and Sea Bottom on Sound Propagation in Persian Gulf
Whether exploratory or commercially, acoustic fishery benefits are important in finding a school of fish and other aquatics, but using this procedure and state accurate detailed information for the whole specifications of organisms require sufficient information of sound speed changes, course of ray propagation and their rate of absorption and attenuation . This research has considered the qua...
متن کامل