Compiler-directed run-time monitoring of program data access

Accurate run-time analysis has been expensive for complex programs, in part because most methods perform on all a data. Some applications require only partial reorganization. An example of this is off-loading infrequently used data from a mobile device. Complete monitoring is not necessary because not all accesses can reach the displaced data. To support partial monitoring, this paper presents a framework that includes a source-to-source C compiler and a run-time monitor. The compiler inserts run-time calls, which invoke the monitor during execution. To be selective, the compiler needs to identify relevant data and their access. It needs to analyze both the content and the location of monitored data. To reduce run-time overhead, the system uses a source-level interface, where the compiler transfers additional program information to reduce the workload of the monitor. The paper describes an implementation for general C programs. It evaluates different levels of data monitoring and their application on an SGI workstation and an Intel PC.