-qarch

@PROCESS

None.

Purpose

Specifies the processor architecture, or family of architectures, where the code may run. This allows the compiler to take maximum advantage of the machine instructions specific to an architecture, or common to a family of architectures.

Syntax


              .-=--pwr8-.   
>>- -q--arch--+-=--auto-+--------------------------------------><
              '-=--pwr9-'

Defaults

-qarch=pwr8
-qarch=auto when -O4 or -O5 is in effect

Parameters

auto: Automatically detects the specific architecture of the compiling machine. It assumes that the execution environment will be the same as the compilation environment. This option is implied if the -O4 or -O5 option is set or implied.
pwr8: Produces object code containing instructions that run on the POWER8® or POWER9™ hardware platforms.
pwr9: Produces object code containing instructions that utilize the POWER9 technology.

Usage

For any given -qarch setting, the compiler defaults to a specific, matching -qtune setting, which can provide additional performance improvements. For detailed information about using -qarch and -qtune together, see -qtune.

Examples

To specify that the executable program testing compiled from myprogram.f is to run on a computer with VSX instruction support, for example, power8, enter:

xlf -o testing myprogram.f -qarch=pwr8

Related information

Compiling for specific architectures

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