Vasudevan Nalini author Columbia University. Computer Science Tardieu Olivier author Dolby Julian author Edwards Stephen A. author Columbia University. Computer Science Columbia University. Computer Science originator contributor text Technical reports New York Department of Computer Science, Columbia University 2008 Clocks are a mechanism for providing synchronization barriers in concurrent programming languages. They are usually implemented using primitive communication mechanisms and thus spare the programmer from reasoning about low-level implementation details such as remote procedure calls and error conditions. Clocks provide flexibility, but programs often use them in specific ways that do not require their full implementation. In this paper, we describe a tool that mitigates the overhead of general-purpose clocks by statically analyzing how programs use them and choosing optimized implementations when available. We tackle the clock implementation in the standard library of the X10 programming language---a parallel, distributed object-oriented language. We report our findings for a small set of analyses and benchmarks. Our tool only adds a few seconds to analysis time, making it practical to use as part of a compilation chain. Computer science CUCS-052-08 http://hdl.handle.net/10022/AC:P:29608 English NNC NNC 2011-04-26 11:13:11 -0400 2011-08-01 12:42:28 -0400 3904 eng