Compaq Fortran includes several directives that support High Performance Fortran (HPF), an extended version of Fortran 90 for parallel programming. Compaq Fortran supports parallel execution of HPF programs on clusters of Tru64 UNIX systems with Message Passing Interface (MPI) installed. Parallel execution can increase performance.
On OpenVMS, Linux, Windows systems, and in programs
compiled without the -hpf option on Tru64 UNIX
systems, the HPF directives are parsed and checked for syntactic
errors, but have no effect on program execution.
HPF directives are preceded by a special prefix that identifies them to the compiler.
There are two kinds of HPF directives: specification and executable. Specification directives must appear in the specification part of a scoping unit. Executable directives must appear in the execution part of a scoping unit.
This section describes syntax rules for the following directives:
| Directive | Kind | |
|---|---|---|
| ALIGN | Specification | Section 15.3.2 |
| DISTRIBUTE | Specification | Section 15.3.3 |
| INDEPENDENT | Executable | Section 15.3.4 |
| INHERIT | Specification | Section 15.3.5 |
| PROCESSORS | Specification | Section 15.3.6 |
| SEQUENCE | Specification | Section 15.3.7 |
| SHADOW | Specification | Section 15.3.8 |
| TEMPLATE | Specification | Section 15.3.9 |