HP Fortran Programmer Guide HP-UX 11i v1, HP-UX 11i v2, and HP-UX 11i v3 (B3908-90032,December 2012)

are assumed to be infrequently called. This option
overrides any information in a profile database.
Generate [do not generate] recovery code for control
speculation. The default is +Onorecovery
+O[no]recovery
+Onoregreassocdisables register reassociation. This
option is only effective at optimization level 2 or higher.
Use +Onoregreassocto disable register reassociation
in the rare case that this optimization degrades
performance.
+O[no]regreassoc
+Oregreassocis the default.
NOTE: This option is valid only on the PA-RISC systems.
+Oreportspecifies the contents of the Optimization
Report.
+O[no]report
All objects of size bytes or smaller will be placed in the
short data area, and references to such data will assume
+Oshortdata[=size]
it resides in the short data area. Valid values of n are 0,
or a decimal number between 8 and 4,194,304 (4MB).
If no size is specified, all data is placed in the short data
area. If size is 0, no data will be placed in the short data
area, and all data references will use long offsets. The
default is +Oshortdata=8.
NOTE: Using a value that is too big or without the
optional size, possibly through +Ofast, may give various
linker fixup errors, if there is more than 4Mb of short
data.
NOTE: All object files participating in a link need to
be consistently compiled with respect to +Oshortdata.
Since the +Ofaster and +Ofast options imply
+Oshortdata, other Fortran object files which reference
common blocks should also be explicitly compiled with
+Oshortdata. Alternatively, the +Ofasterand
+Ofastcompilations can be compiled with an additional
+Oshortdata=8appended to the command line.
Optimize with the assumption that the specified
subprograms do [do not] modify global variables. This
+O[no]sideeffects=name1, name2,...nameN
option can be used at optimization level 2 or higher. The
default is to assume that all subprograms have side effects
unless the optimizer can determine that there are none.
Enables [disables] the use of static branch prediction for
decision on conditional branches. This is more applicable
+O[no]static_prediction
to large programs with poor locality. This option is
available at optimization level 3 and above.
NOTE: This option is valid only on the PA-RISC systems.
Preserve [do not preserve] the original program order
for stores to memory that is potentially visible to multiple
+O[no]store_ordering
threads. This does not imply strong ordering. The default
is +Onostoreordering.
+Ovectorizecauses the compiler to replace certain
loops with calls to the math library. This option is only
effective at optimization level 3 or higher.
If you link separately from the command line and you
compiled with the +Ovectorizeoption, you must ensure
that the link line causes the math library to be searched.
+O[no]vectorize
+Onovectorizeis the default.
NOTE: This option is valid only on the PA-RISC systems.
Assert [do not assert] that only files compiled with this
option directly reference any global variables and
+O[no]whole_program_mode
Fine-tuning optimization options 47