-qtune

Description

Specifies the architecture system for which the executable program is optimized.

Syntax

Read syntax diagramSkip visual syntax diagram                 .-pwr4---.
>>- -q--tune--=--+-auto---+------------------------------------><
                 +-ppc970-+
                 +-pwr3---+
                 +-pwr5---+
                 +-rs64b--+
                 '-rs64c--'
 

where architecture suboptions are:

auto Produces object code optimized for the platform on which it is compiled.
ppc970 Produces object code optimized for the PowerPC 970 processor.
pwr3 Produces object code optimized for the POWER3 hardware platforms.
pwr4 Produces object code optimized for the POWER4 hardware platforms.
pwr5 Produces object code optimized for the POWER5 hardware platforms.
rs64b Produces object code optimized for the RS64II processor.
rs64c Produces object code optimized for the RS64III processor.

See also #pragma options.

Default

The default setting of the -qtune option depends on the setting of the -qarch option.

Default -qtune settings for specific -qarch settings are described in Acceptable compiler mode and processor architecture combinations.

Notes

You can use -qtune=suboption with -qarch=suboption.

Example

To specify that the executable program testing compiled from myprogram.C is to be optimized for a POWER3 hardware platform, enter:

xlc++ -o testing myprogram.C -qtune=pwr3

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