HP aC++/HP C A.06.20 Programmer's Guide

+Onoptrs_strongly_typed is synonymous to +Otype_safety=off.

NOTE: This option is supported in C-mode only. A warning is displayed in C++ when

this option is used.

+O[no]ptrs_to_globals[=list]

The +O[no]ptrs_to_globals option tells the optimizer whether global variables

are accessed [are not accessed] through pointers. If +Onoptrs_to_globals is specified,

it is assumed that statically-allocated data (including file-scoped globals, file-scoped

statics, and function-scoped statics) will not be read or written through pointers. The

default is +Onoptrs_to_globals.

+O[no]size

While most optimizations reduce code size, the +Osize option suppresses those few

optimizations that significantly increase code size. The +Onosize option enables

code-expanding optimizations.

Use +Osize at all optimization levels. The default is +Onosize.

Advanced +Ooptimization Options

Advanced optimization options provide additional control for special situations.

+O[no]cross_region_addressing

The +O[no]cross_region_addressing option enables [disables] the use of

cross-region addressing. Cross-region addressing is required if a pointer, such as an

array base, points to a different region than the data being addressed due to an offset

that results in a cross-over into another region. Standard conforming applications do

not require the use of cross-region addressing.

The default is +Onocross_region_addressing.

NOTE: Using this option may result in reduced runtime performance.

+O[no]datalayout

The +O[no]datalayout option enables [disables] profile-driven layout of global and

static data items to improve cache memory utilization. This option is currently enabled

if +Oprofile=use (dynamic profile feedback) is specified.

Code Optimizing Options 73