 






     Software
     Product
     Description

     ________________________________________________________________

     PRODUCT NAME:  VAX FORTRAN High-Performance Option,SPD 32.67.02
                    Version 1.2

     DESCRIPTION

     The VAX FORTRAN High-Performance Option (HPO) is an optional
     enhancement to the VAX FORTRAN compiler. HPO enables the FORTRAN
     compiler to automatically generate vector-processor instructions
     and to automatically decompose programs to improve performance
     on multiple-processor systems.

     HPO adds a new ASSERT statement that provides additional infor-
     mation to the compiler about the program. The ASSERT statement
     can be used in some programs to achieve a high degree of vector-
     ization and/or automatic decomposition. The ASSERT statement can
     optionally generate code to verify the assertions at run-time,
     if desired. ASSERT statements can be specified in directive form
     for portability and will be ignored by other compilers since
     they will appear as comments.

     HPO also adds the INIT_DEP_FWD directive to allow vector pro-
     cessing for many loops that would otherwise not qualify due
     to unknown data dependences. As this directive may change the
     meaning of the program, Digital Equipment Corporation does not
     warrant execution results conforming to the FORTRAN standard
     when this directive is used.

     Additional Features

     o  Optimized vector code generation for solving dense systems of
        linear equations

     o  The /MATH_LIBRARY qualifier to support performance optimized
        vector math functions

                                  DIGITAL                   June 1991

                                                          AE-PC9JC-TE

 


     VAX FORTRAN High-Performance Option,               SPD 32.67.02
     Version 1.2


     o  The /CHECK=ALIGNMENT qualifier to suppress vector alignment
        exceptions at run-time

     o  The NOVECTOR directive to allow the programmer to control the
        presence and level of vectorization in each nest of DO-loops

     HPO includes the following enhancements to VAX FORTRAN:

     o  Thorough dependence analysis

     o  Automatic transformations for vectorizing difficult con-
        structs

     o  Multi-level vectorization and decomposition

     o  Compile-time performance analysis to choose the best vector-
        ization and/or decomposition method

     o  Integration of vector and scalar optimizations

     o  Generation of diagnostics for vectorization inhibitors

        -  Though some vector inhibition diagnostics will display
           in the listing and on the termainal, the VAX Language-
           Sensitive Editor component of the VAX Language-Sensitive
           Editor/Source Code Analyzer is required to display all the
           vector inhibition diagnostics generated by the compiler.

     o  Loop summary listing for viewing optimization results

     HARDWARE REQUIREMENTS

     VAX, MicroVAX, VAXstation, or VAXserver configuration as speci-
     fied in the System Support Addendum (SSA 32.67.02-x).





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     VAX FORTRAN High-Performance Option,               SPD 32.67.02
     Version 1.2


     SOFTWARE REQUIREMENTS

     For Systems Using Terminals (No DECwindows Interface):

     VMS Operating System
     VAX FORTRAN

     For Workstations Running VWS:

     VMS Operating System
     VMS Workstation Software
     VAX FORTRAN

     For Workstations Running DECwindows:

     VMS Operating System (and necessary components of VMS DECwin-
     dows)
     VAX FORTRAN

     Refer to the System Support Addendum (SSA 32.67.02-x) for avail-
     ability and required versions of prerequisite/optional software
     and for information regarding components of VMS DECwindows.

     ORDERING INFORMATION

     Software Licenses: QL-YHBA*-**
     Software Media: QA-YHBA*-**
     Software Documentation: QA-YHBAA-GZ
     Software Product Services: QT-YHBA*-**

     *  Denotes variant fields. For additional information on avail-
        able licenses, services, and media, refer to the appropriate
        price book.

     SOFTWARE LICENSING

     This software is furnished under the licensing provisions of
     Digital Equipment Corporation's Standard Terms and Conditions.
     For more information about Digital's licensing terms and poli-
     cies, contact your local Digital office.

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     VAX FORTRAN High-Performance Option,               SPD 32.67.02
     Version 1.2


     LICENSE MANAGEMENT FACILITY SUPPORT

     This layered product supports the VMS License Management Facil-
     ity.

     License units for this product are allocated on a CPU-capacity
     basis.

     For more information on the License Management Facility, refer
     to the VMS Operating System Software Product Description (SPD
     25.01.xx) or the License Management Facility manual of the VMS
     Operating System documentation set.

     For more information about Digital's licensing terms and poli-
     cies, contact your local Digital office.

     SOFTWARE PRODUCT SERVICES

     A variety of service options are available from Digital. For
     more information, contact your local Digital office.

     SOFTWARE WARRANTY

     Warranty for this software product is provided by Digital with
     the purchase of a license for the product as defined in the
     Software Warranty Addendum of this SPD.

     [TM] The DIGITAL Logo, DECwindows, MicroVAX, VAX, VAXcluster,
          VAX FORTRAN, VAXft, VAXserver, VAXstation, and VMS are
          trademarks of Digital Equipment Corporation.









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