Intel® Fortran Compiler 17.0 Developer Guide and Reference

qopt-matmul, Qopt-matmul

Enables or disables a compiler-generated Matrix Multiply (matmul) library call. Option -qopt-matmul is the replacement option for -opt-matmul, which is deprecated.

Architecture Restrictions

Not available on Intel® 64 architecture targeting the Intel® Xeon Phi™ coprocessor x100 product family (formerly code name Knights Corner)

Syntax

Linux:

-qopt-matmul

-qno-opt-matmul

macOS:

None

Windows:

/Qopt-matmul

/Qopt-matmul-

Arguments

None

Default

-qno-opt-matmul
or/Qopt-matmul-

The matmul library call optimization does not occur unless this option is enabled or certain other compiler options are specified (see below).

Description

This option enables or disables a compiler-generated Matrix Multiply (MATMUL) library call.

The [q or Q]opt-matmul option tells the compiler to identify matrix multiplication loop nests (if any) and replace them with a matmul library call for improved performance. The resulting executable may get additional performance gain on Intel® microprocessors than on non-Intel microprocessors.

Note

This option is dependent upon the OpenMP* library. If your product does not support OpenMP, this option will have no effect.

This option is enabled by default if options O3 and [Q]parallel are specified. To disable this optimization, specify -qno-opt-matmul or /Qopt-matmul-.

This option has no effect unless option O2 or higher is set.

Note

Many routines in the MATMUL library are more highly optimized for Intel® microprocessors than for non-Intel microprocessors.

IDE Equivalent

Visual Studio: Optimization > Enable Matrix Multiply Library Call

Eclipse: None

Xcode: None

Alternate Options

None

See Also