HP Fortran Programmer's Guide (March 2010)

Using Fortran directives
Using HP Fortran directives
Chapter 9216
Using HP Fortran directives
HP Fortran provides a number of compiler directives that are useful for controlling certain
functions (for example, optimization) within the source file. Table 9-1 lists and briefly
describes these directives; they are listed in the order in which they appear in the sections
below.
NOTE For a detailed description of Optimization directives, Parallelizing directives,
OpenMP directives and Data privatization directives, see Parallel
Programming Guide for HP-UX Systems.
Table 9-1 HP Fortran directives
Directive Function
$HP$ ALIAS Associates the name of a subroutine,
function, entry, or common block with an
external name.
$HP$ CHECK_OVERFLOW Generates code to trap integer overflows.
$HP$ LIST Controls output of source lines in listing
file.
$HP$ OPTIMIZE Controls optimization within the source
file.
$HP$ ESTIMATED
FREQUENCY
Passes on to the compiler an estimate of
how frequently the current block is
executed.
If the current block is an 'if' block, then 'f'
must be 0 <= f <= 1. In this case, 'f'
indicates the probability of executing this
block compared to the corresponding 'if'
block. If the current block is a loop, then 'f'
must be f >= 0. In this case, 'f' indicates
the number of times the loop might get
executed (trip count).