Intel® Advisor Help
To vectorize a loop using the Compiler's automatic vectorization, remove any restrictions that prevent the compiler from automatic vectorization of the target loop. Normally, the compiler reports the loops that were not vectorized and explains why. So the most obvious way to enable automatic vectorization for the target loop is to change the source code so that it contains no restrictions for the automatic vectorization.
Consider using the Intel® Advisor Compiler Diagnostic Details tab that is populated with the Compiler's report data upon running the Survey Analysis. The Compiler Diagnostic Details tab usually contains information that explains why the loop was not vectorized, and gives recommendations that might help you to add vectorization.
You can also generate a vectorization report using the Qopt report compiler options, which are OS-specific. After you add the option, you get the report with the list of loops that were not vectorized, along with the reason why the compiler did not vectorize.
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