Intel® C++ Compiler Classic Developer Guide and Reference

ID 767249
Date 3/31/2023
Public

A newer version of this document is available. Customers should click here to go to the newest version.

Document Table of Contents

fimf-force-dynamic-target, Qimf-force-dynamic-target

Instructs the compiler to use run-time dispatch in calls to math functions.

Syntax

Linux:

-fimf-force-dynamic-target[=funclist]

macOS:

-fimf-force-dynamic-target[=funclist]

Windows:

/Qimf-force-dynamic-target[:funclist]

Arguments

funclist

Is an optional list of one or more math library functions to which the attribute should be applied. If you specify more than one function, they must be separated with commas.

Precision-specific variants like sin and sinf are considered different functions, so you would need to use -fimf-dynamic-target=sin,sinf (or /Qimf-dynamic-target:sin,sinf) to specify run-time dispatch for both the single-precision and double-precision sine functions.

You also can specify the symbol /f to denote single-precision divides, symbol / to denote double-precision divides, symbol /l to denote extended-precision divides, and symbol /q to denote quad-precision divides. For example, you can specify -fimf-dynamic-target=/ or /Qimf-dynamic-target:/.

Default

OFF

Run-time dispatch is not forced in math libraries calls. The compiler can choose to call a CPU-specific version of a math function if one is available.

Description

This option instructs the compiler to use run-time dispatch in calls to math functions. When this option set to ON, it lets you force run-time dispatch in math libraries calls.

By default, when this option is set to OFF, the compiler often optimizes math library calls using the target CPU architecture-specific information available at compile time through the [Q]x and arch compiler options.

If you want to target multiple CPU families with a single application or you prefer to choose a target CPU at run time, you can force run-time dispatch in math libraries by using this option.

Product and Performance Information

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

Notice revision #20201201

IDE Equivalent

None

Alternate Options

None

See Also