Increasing focus on multimedia applications has prompted the addition of multimedia extensions to most existing general-purpose microprocessors. This added functionality comes primarily with the addition of short SIMD instructions. Unfortunately, access to these instructions is limited to in-line assembly and library calls. Generally, it has been assumed that vector compilers provide the most promising means of exploiting multimedia instructions. Although vectorization technology is well understood, it is inherently complex and fragile. In addition, it is incapable of locating SIMD-style parallelism within a basic block. In this thesis we introduce the concept of Superword Level Parallelism (SLP), a novel way of viewing parallelism in multimedia and scientific applications. We believe SLP is fundamentally different from the loop level parallelism exploited by traditional vector processing, and therefore demands a new method of extracting it. We have developed a simple and robust compiler for detecting SLP that targets basic blocks rather than loop nests. As with techniques designed to extract ILP, ours is able to exploit parallelism both across loop iterations and within basic blocks. The result is an algorithm that provides excellent performance in several application domains. In our experiments, dynamic instruction counts were reduced by 46%. Speedups ranged from 1.24 to 6.70.

Abstract-This paper introduces the use of adaptive multichannel discrete wavelet transforms (AMDWTs), allowing for a customized design of optimum mother wavelets, for the detection of a constituent absorption band within a hyperspectral curve. Even when the target's amplitude is only 3% of the background signal's amplitude, the AMDWT approach produces target detection rates of 90%.

A static memory reference exhibits a unique property when its dynamic memory addresses are congruent with respect to some non-trivial modulus. Extraction of this congruence information at compile-time enables new classes of program optimization. In this paper, we present methods for forcing congruence among the dynamic addresses of a memory reference. We also introduce a compiler algorithm for detecting this property. Our transformations do not require interprocedural analysis and introduce almost no overhead. As a result, they can be incorporated into real compilation systems.

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