on Itanium®-based systems for HP Fortran Version 3.2

 

and later. You can use the +Oautopar option instead

 

of +Oparallel on Itanium® based systems.

 

NOTE: The +Oparallel option should not be used

 

for programs that make explicit calls to the kernel threads

 

library.

+Oparallel_intrinsics

+Oparallel_intrinsics links in the parallel version

 

of many of the Fortran intrinsics located in

 

libF90_parallel.

+O[no]parmsoverlap

+Oparmsoverlap causes the optimizer to assume that

 

the actual arguments of function calls overlap in memory,

 

thus preventing any optimizations that violate this

 

assumption. This option is only effective at optimization

 

level 2 or higher.

 

Use the +Onoparmsoverlapoption with programs that

 

conform to the standard requirement that parameters

 

must not overlap

 

The default is+Onoparmsoverlap.

+O[no]pipeline

+Opipelineenables software pipelining. This option is

 

only effective at optimization level 2 or higher. Use

 

+Onopipeline(disable software pipelining) to conserve

 

code space. The default is +Opipeline.

 

NOTE: This option is valid only on the PA-RISC systems.

+Oprefetch_latency=num option

Applies to loops for which the compiler generates data

 

prefetch instructions. For a given loop, the compiler

 

divides “cycles” by the estimated loop length to arrive

 

at the number of loop iterations for which to generate

 

advance prefetches. The default value is 480 cycles for

 

loops containing floating-point accesses and 150 cycles

 

for loops that do not contain any floating-point accesses.

 

For tuning purposes, it is recommended that users

 

measure their application’s performance using a few

 

different prefetch latency settings to determine the optimal

 

value. Some floating-point codes may benefit by

 

increasing the distance to 960. Parallel applications

 

frequently benefit from a shorter prefetch distance of 150.

+O[no]procelim

When +Oprocelimis specified, procedures that are not

 

referenced by the application are eliminated from the

 

output executable file. When +Onoprocelim is

 

specified, procedures that are not referenced by the

 

application are not eliminated from the output executable

 

file. You can use this option at any level of optimization.

 

Use +Oprocelimto reduce the size of the executable

 

file, especially when optimizing at levels 3 and 4, when

 

inlining can remove all calls to some routines.

 

The default is +Onoprocelimat levels 0-3, and

 

+Oprocelimat level 4.

+Oprofile=use:filename

Specify filname as the name of the profile database file.

 

This option is a synonym for the +P, +dffilename

 

options.The :filename argument is optional (the default

 

filename is flow.data). See ld (1), +P, and +df for

 

more details. This option is only valid for Itanium®-based

 

applications.

+Oprofile=collect<qualifiers>

In the absence of qualifiers, +Oprofile=collectis

 

the same as +I.

 

< qualifiers > are a comma-separated list of profile

 

collection qualifiers. Supported profile collection qualifiers

 

are :

Fine-tuning optimization options

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