Organization of this Document

Section , this section, presents an overview of HPF.

Section sets out some basics of HPF, including:

• The reasons for using Fortran 90 as a base language;

• A partial cost model for HPF programs; and

• Lexical rules for HPF directives.

Section describes the facilities for data partitioning in HPF. These include:

• The distribution model;

• Features for distributing array elements among processors;

• Features for aligning array elements which are accessed together; and

• Features for mapping ALLOCATABLE arrays, pointers, and dummy procedure arguments.

Section describes the explicitly parallel statement types in HPF. These include:

• The single- and multi-statement forms of the FORALL parallel construct;

• Pure functions callable from within FORALL; and

• The INDEPENDENT assertion for loops.

Section describes new standard functions available in HPF. These include:

• Inquiry intrinsic functions to check system and data partitioning status;

• New computational intrinsic functions and extensions to existing intrinsic functions; and

• A standard library of computational and inquiry functions.

Section describes extrinsic procedures in HPF, particularly the EXTRINSIC procedure interface. The material in Annex builds on this interface.

Section describes the treatment of sequence and storage association in HPF. This includes:

• Limitations on storage association of explicitly distributed variables; and

• Limitations on sequence association of explicitly distributed variables.

Section describes Subset HPF, which may be implemented more quickly than full HPF. This includes:

• A list of Fortran 90 features that are in Subset HPF;

• A list of HPF features that are not in Subset HPF; and

• Discussions of why these decisions were made.

Annex describes a binding for a local execution model for use as an EXTRINSIC option. The model implements the Single Program Multiple Data programming paradigm, which has wide (but not universal) applicability.

Annex collects the grammar and syntactic constraints for HPF defined in the main text of this document.

Annex cross-references the BNF terminals and nonterminals defined and used in this document.

The Bibliography provides references to various HPF sources:

• Fortran standards;

• Fortran implementations;

• Books about Fortran 90; and

• Technical papers.