Intel® C++ Compiler Classic Developer Guide and Reference

ID 767249
Date 3/31/2023
Public

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Guided Auto Parallelism Messages

The Guided Auto Parallelism (GAP) messages provide advice that should improve optimizations.

The messages provide suggestions for:

  • Automatic parallelization of loop nests

  • Automatic vectorization of inner loops

  • Data transformation

You must decide whether to follow a particular suggestion. For example, if the advice is to apply a particular pragma, you must understand the semantics of the pragma and carefully consider whether it can be safely applied to the loop (or loop nest) in question.

If you apply the pragma improperly, the compiler may generate incorrect code, causing the application to execute incorrectly.

If you do not fully understand the suggested advice, please refer to the relevant topics in the compiler documentation before applying that advice.

Once you apply the suggested advice, the compiler assumes that it is correct and it does not perform any checks or issue any warnings.

In general, messages that relate to loops tend to target vectorization and/or parallelization of loops. If you are not familiar with loop optimizations, please refer to the compiler documentation on this kind of optimization.