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The C251 compiler is an optimizing compiler. This means that the compiler takes certain steps to ensure that the code that is generated and output to the object file is the most efficient (smaller and/or faster) code possible. The compiler analyzes the generated code to produce more efficient instruction sequences. This ensures that your C251 program runs as quickly as possible.

The C251 compiler provides six different levels of optimizing. Each increasing level includes the optimizations of the levels below it. Refer to the OPTIMIZE directive for more information on the various optimization levels that are available.

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