10.6 Super-optimizers

Although code optimization certainly improves a code, it does not deliver an optimum final code in the sense of minimum possible time and space requirements.

Super-optimizers are an attempt to develop optimization strategies to reach this theoretical limit. As in the final analysis, the fastest or the smallest program can be written with reference to a particular processor only, such super-optimizers are in general processor specific. The general approach is to find a least-time or the shortest sequence of instructions for a particular processor which will be equivalent – in terms of its semantics – to the given raw target code. As will be evident from the example given below, the instruction sequence which emerges may look ...

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