Specifications

Compilers, Interpreters, and Assemblers
7.11 Fortran
• Numerous OpenVMS features and layered products, including:
All OpenVMS (RMS) file formats
Access to object files created by other Digital languages and support of
the OpenVMS calling standard
Creation of shareable images usable by any program written in a native
Digital language
Invoking all callable system routines, including the use of the
FORSYSDEF library definitions for calling system services
Conversion of unformatted nonnative floating-point data to the selected
memory format, including several big endian data formats
Selection of the floating-point data type used in memory
Support for the CDD/Repository
Use of all OpenVMS programming utilities
VAX
DEC Fortran for OpenVMS VAX Systems (previously called VAX FORTRAN) also
provides parallel processing support (both automatic and directed).♦
AXP
DEC Fortran for OpenVMS AXP Systems also provides data alignment control
and the use of IEEE and most VAX floating-point data types in memory.♦
7.12 MACRO
The OpenVMS operating system supports the following assembly language
products:
• VAX MACRO
• MACRO-32 Compiler for OpenVMS AXP
• MACRO-64 Assembler for OpenVMS AXP
7.12.1 VAX MACRO
VAX MACRO is an assembly language for programming a VAX computer under
the OpenVMS operating system. The instruction set includes approximately 130
instructions and 70 directives, which enable complex programming statements. It
can use all OpenVMS resources. For example, it can invoke any callable system
routine, use the OpenVMS Debugger and other utilities, and call any object
module written in another VAX language.
General assembler directives can perform the following operations:
• Store data or reserve memory for data storage
• Control the alignment of parts of the program in memory
• Specify the methods of accessing the sections of memory in which the program
will be stored
• Specify the entry point of the program or a part of the program
• Specify the way in which symbols are referenced
• Specify that a part of the program is to be assembled only under certain
conditions
• Control the format and content of the listing file
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