This work proposed a performance improvement of a stack-based virtual mchine by augmenting the instruction set with one-address instructions. The extended instructions are binary operators with two addressing modes: access local variables and immediate mode. An experiment is carried out to measure the effectiveness of the proposal based on modification of a stack-based virtual machine to includ...

Simultaneous Multithreading (SMT) has become common in commercially available processors with hardware support for dual contexts of execution. However, performance of SMT systems has been disappointing for many applications. Consequently, many SMT systems are operated in a single-context configuration to achieve better average throughput, depending on the application domain. This paper first ex...

Dynamic Voltage Scaling (DVS) is a promising method to achieve energy saving by slowing down the processor into multiple frequency levels in battery-operated embedded systems. However, the worst case execution time (WCET) of the tasks scheduled by DVS must be known ahead of time to ensure their schedulability. In reality, a system's workloads may change significantly without satisfying any pred...

We propose a safe design method for safe execution systems, based on faulttolerance techniques: it uses optimal discrete controller synthesis (DCS) to generate a correct-by-construction fault-tolerant system. The properties enforced concern consistent execution, functionality fulfillment (whatever the faults, under some failure hypothesis), and several optimizations (of the tasks’ execution tim...

Embedded systems require safe design methods based on formal methods, as well as safe execution based on fault-tolerance techniques. We propose a safe design method for safe execution systems: it uses discrete controller synthesis (DCS) to generate a correct reconfiguring system. The properties enforced concern consistent execution, functionality fulfillment (whatever the faults, under some fai...

We present the design and implementation of a debugging tool that displays a message-passing graph of the execution of an MPI application. Parts of the graph can be hidden or highlighted based on the stack trace, calling process or communicator of MPI calls. The tool incorporates several features enabling developers to explicitly control the ordering of message-passing events during the executi...

As software systems have grown large and complex in the last few years, the problems with which Model-Driven Development has to cope have increased at the same pace. In particular, the need to improve the performance and scalability of model transformations has become a critical issue. In previous work we introduced LinTra, a model transformation platform for the parallel execution of out-place...

We present an execution-flow analysis for JavaScript programs running in a web browser to prevent Cross-site Scripting (XSS) attacks. We construct finite-state automata (FSA) to model the client-side behavior of Ajax applications under normal execution. Our system is deployed in proxy mode. The proxy analyzes the execution flow of client-side JavaScript before the requested web pages arrive at ...