HP Fortran Programmer's Guide (September 2007)

Using Fortran directives

Compatibility directives

Chapter 9210

Compatibility directives

HP Fortran supports the compiler directives listed in Table 9-2. These directives are provided

for compatibility with programs developed on the platforms listed in the table.

In ﬁxed format, each directive must be preceded by the comment character C, !,or* and must

begin in column 1 of the source ﬁle. In free format, the directive must be preceded by the

Fortran comment character (!).

If an option or argument is included with the directive name, the compiler ignores the

directive.

The following sections describes these directives in detail.

Controlling vectorization

HP Fortran can vectorize eligible program loops that operate on vectors. This optimization

causes the compiler to replace the loops with calls to selected routines in the Basic Linear

Algebra Subroutine (BLAS) library. You can use the *$* [NO]VECTORIZE directive to enable

or disable vectorization. The compiler considers the *$* VECTORIZE directive as a request to

vectorize a loop. If the compiler determines that it cannot proﬁtably or safely vectorize the

loop, it ignores the directive.

Table 9-2 Compatibility directives recognized by HP Fortran

Vendor Directive

Cray DIR$ NO SIDE EFFECTS

DIR$ [NO]CONCUR

DIR$ IVDEP

FPP$ NODEPCHK

KAP *$* [NO]CONCURRENTIZE

*$* [NO]VECTORIZE

VAST VD$ NODEPCHK