Analysis of High-level Address Code Transformations for Programmable Processors

Memory intensive applications require considerable arithmetic for the computation and selection of the different memory access pointers. These memory address calculations often involve complex (non)linear arithmetic expressions which have to be calculated during program execution under tight timing constraints, thus becoming a crucial bottleneck in the overall system performance. This paper explores applicability and effectiveness of sourcelevel optimisations (as opposed to instruction-level) for address computations in the context of multimedia. We propose and evaluate two processor-target independent source-level optimisation techniques, namely, global scope operation cost minimisation complemented with loop-invariant code hoisting, and non-linear operator strength reduction. The transformations attempt to achieve minimal code execution within loops and reduced operator strengths. The effectiveness of the transformations is demonstrated with two real-life multimedia applica..

Reuse Analysis of Indirectly Indexed Arrays JAVED ABSAR

We propose techniques for identifying and exploiting spatial and temporal reuse for indirectly indexed arrays. Indirectly indexed arrays are those arrays which are, typically, accessed inside multi-level loop nest and whose index expression includes not only loop iterators and constants but arrays as well. Existing techniques for improving locality are quite sophisticated in the case of directly indexed arrays. But, unfortunately, they are inadequate for handling indirectly indexed arrays. In this paper, we, therefore, extend the existing framework and techniques of directly indexed to indirectly indexed arrays. Concept of reuse subspace, dependence vector, self and group reuse are extended and applied in this new context. Also, lately scratch-pad memory has become an attractive alternative to data-cache, specially in the embedded multimedia community. This is because embedded systems are very sensitive to area and energy and the scratch-pad is smaller in area and consumes lesser energy on a per access basis compared to the cache of the same capacity. Several techniques have been proposed in the past for efficient exploitation of scratch-pad for directly indexed arrays. We extend these techniques by presenting a method for scratch-pad mapping of indirectly indexed arrays. This enables the scratch-pad to be used in a larger context than was possible before

Stigma bij schizofrenie

BACKGROUND Schizophrenia not only debilitates and imposes restrictions on patients, but it can also stigma, a phenomenon that radically alters the lives of patients and their families. AIM To conduct a review of the research literature on the factors that cause, facilitate and heighten the effects of stigma in patients and their relatives, and to discover possible ways of dispelling or preventing stigma. METHOD A literature search was carried out using Medline and Psychinfo (1990 till march 2001), using as key words schizophrenia, psychosis and stigma. RESULTS AND CONCLUSIONS Stigma seriously affects the lives of patients suffering from psychotic disorders. Most studies agree on this point. There are indications that stigma lowers the self-esteem of both patients and their families. However, the causes of stigma are usually described in very vague terms that have little scientific basis. Hardly any research has been done on possible ways of tackling stigma. The ways that have been proposed are either inadequate or are difficult to implement. Among the strategies that are likely to combat stigma effectively are therapy, social reintegration, improved therapy and education of the public. Stigma will not be fully understood until more research is done into patients, their families and the public as a whole.status: publishe