Intel® Fortran Compiler Classic and Intel® Fortran Compiler Developer Guide and Reference

ID 767251
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A newer version of this document is available.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

qopt-jump-tables, Qopt-jump-tables

Enables or disables generation of jump tables for switch statements. This feature is only available for ifort.

Syntax

Linux:

-qopt-jump-tables=keyword

-qno-opt-jump-tables

macOS:

-qopt-jump-tables=keyword

-qno-opt-jump-tables

Windows:

/Qopt-jump-tables:keyword

/Qopt-jump-tables-

Arguments

keyword

Is the instruction for generating jump tables. Possible values are:

never

Tells the compiler to never generate jump tables. All switch statements are implemented as chains of if-then-elses. This is the same as specifying -qno-opt-jump-tables (Linux* and macOS) or /Qopt-jump-tables- (Windows*).

default

The compiler uses default heuristics to determine when to generate jump tables.

large

Tells the compiler to generate jump tables up to a certain pre-defined size (64K entries).

n

Must be an integer. Tells the compiler to generate jump tables up to n entries in size.

Default

-qopt-jump-tables=default
or /Qopt-jump-tables:default

The compiler uses default heuristics to determine when to generate jump tables for switch statements.

Description

This option enables or disables generation of jump tables for switch statements. When the option is enabled, it may improve performance for programs with large switch statements.

IDE Equivalent

None

Alternate Options

None