Dimensionamento de processadores com arquitetura horizontal para exploração de micro e mesoparalelismo
Abstract
Horizontal architectures can control several functional units independently, and usually have a single flow of control. As such, they exploit only the finer parallelism, and a large number of functional units is useless when the code contains control or data dependencies. Performance can be increased, with the same total hardware, if the functional units are divided in groups, each with a private register file and with an independent flow of control. This will neither impair the performance when many functional units are required, nor affect the cycle time adversely. Very important side effects are the reduction on the numberof ports in the central register file, with reduction of the instruction size as well. Results are presented for a processor showing that improvements in the range of 2.4 can be achieved in the geometric mean of performance when executing the Lawrence Livermore Kernels.
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