Developer Guide and Reference

Contents

Pragmas

Pragmas are directives that provide instructions to the compiler for use in specific cases. For example, you can use the
novector
pragma to specify that a loop should never be vectorized. The keyword
#pragma
is standard in the C++ language, but individual pragmas are machine-specific or operating system-specific, and vary by compiler.
Some pragmas provide the same functionality as compiler options. Pragmas override behavior specified by compiler options.
Some pragmas are available for both Intel® and non-Intel microprocessors but they may perform additional optimizations for Intel® microprocessors than they perform for non-Intel microprocessors. Refer to the individual pragma name for detailed description.
The
Intel® oneAPI
DPC++/C++
Compiler
pragmas are categorized as follows:
  • Intel-specific Pragmas - pragmas developed or modified by Intel to work specifically with the
    Intel oneAPI
    DPC++/C++
    Compiler
  • Intel Supported Pragmas - pragmas developed by external sources that are supported by the
    Intel oneAPI
    DPC++/C++
    Compiler
    for compatibility reasons

Using Pragmas

You enter pragmas into your C++ source code using the following syntax:
#pragma <pragma name>

Individual Pragma Descriptions

Each pragma description has the following details:
Section
Description
Short Description
Contains a brief description of what the pragma does.
Syntax
Contains the pragma syntax.
Arguments
Contains a list of the arguments (parameters).
Description
Contains a detailed description of what the pragma does.
Example
Contains typical usage example/s.
See Also
Contains links or paths to other pragmas or related topics.

Product and Performance Information

1

Performance varies by use, configuration and other factors. Learn more at www.Intel.com/PerformanceIndex.