Intel® Fortran Compiler

Developer Guide and Reference

ID 767251
Date 10/15/2026
Public
Document Table of Contents

floop-unroll-and-jam, Qloop-unroll-and-jam

Enables or disables the loop unroll-and-jam optimization done by the compiler as part of loop transformations.

Syntax

Linux:

-floop-unroll-and-jam

-fno-loop-unroll-and-jam

Windows:

/Qloop-unroll-and-jam

/Qloop-unroll-and-jam-

Arguments

None

Default

-floop-unroll-and-jam
or /Qloop-unroll-and-jam

Loop unroll-and-jam is performed during loop transformation at optimization levels of O2 and above.

Description

This option enables or disables the loop unroll-and-jam optimization done by the compiler as part of loop transformations. Unroll-and-jam partially unrolls one or more outer loops in a nest and then fuses, or jams, the resulting inner loop bodies together, which can improve reuse of data in registers and cache and increase the amount of work available for vectorization. This option takes effect only if you specify an optimization level of O2 or higher.

IDE Equivalent

None

Alternate Options

None

See Also