VAX Macro
Encyclopedia
VAX Macro is the computer assembly language
implementing the instruction set for the line of CPUs designed to run the OpenVMS
operating system created by Digital Equipment Corporation
in 1977. OpenVMS
now belongs to Hewlett-Packard
.
The syntax, directives, macro language, and lexical substitution operators of VAX Macro previously appeared in Macro-11, the assembler for the PDP-11
series of computers. VAX Macro or, as it was also known, Macro-32, supported the VAX
processors developed and manufactured by Digital Equipment Corporation
. It ran under the VAX/VMS operating system and produced object files suitable for the VAX/VMS linker. The Macro-32 assembler (and the linker) were bundled with the operating system.
With the advent of the 64-bit Alpha AXP chip, VAX Macro essentially became VMS Macro. Macro-32 was supported on the Alpha architecture, but because the Alpha used a different instruction set, the Macro-32 assembly language no longer mapped to the native instruction set. Macro-32 under the Alpha architecture was actually implemented then as a compiler, compiling VAX assembly language into Alpha instructions. Unlike most compilers, however, Macro-32 for Alpha performed no optimization, retaining as much as possible the programmer's direct control over the generated code.
The Alpha AXP chips introduced to the VMS world then the latest progression of the VMS Macro language, supporting the underlying RISC instruction set, and was called Macro-64.
A compiler from Macro-32 is available for Intel Itanium architecture A significant part of OpenVMS is written with Macro-32.
Assembly language
An assembly language is a low-level programming language for computers, microprocessors, microcontrollers, and other programmable devices. It implements a symbolic representation of the machine codes and other constants needed to program a given CPU architecture...
implementing the instruction set for the line of CPUs designed to run the OpenVMS
OpenVMS
OpenVMS , previously known as VAX-11/VMS, VAX/VMS or VMS, is a computer server operating system that runs on VAX, Alpha and Itanium-based families of computers. Contrary to what its name suggests, OpenVMS is not open source software; however, the source listings are available for purchase...
operating system created by Digital Equipment Corporation
Digital Equipment Corporation
Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
in 1977. OpenVMS
OpenVMS
OpenVMS , previously known as VAX-11/VMS, VAX/VMS or VMS, is a computer server operating system that runs on VAX, Alpha and Itanium-based families of computers. Contrary to what its name suggests, OpenVMS is not open source software; however, the source listings are available for purchase...
now belongs to Hewlett-Packard
Hewlett-Packard
Hewlett-Packard Company or HP is an American multinational information technology corporation headquartered in Palo Alto, California, USA that provides products, technologies, softwares, solutions and services to consumers, small- and medium-sized businesses and large enterprises, including...
.
The syntax, directives, macro language, and lexical substitution operators of VAX Macro previously appeared in Macro-11, the assembler for the PDP-11
PDP-11
The PDP-11 was a series of 16-bit minicomputers sold by Digital Equipment Corporation from 1970 into the 1990s, one of a succession of products in the PDP series. The PDP-11 replaced the PDP-8 in many real-time applications, although both product lines lived in parallel for more than 10 years...
series of computers. VAX Macro or, as it was also known, Macro-32, supported the VAX
VAX
VAX was an instruction set architecture developed by Digital Equipment Corporation in the mid-1970s. A 32-bit complex instruction set computer ISA, it was designed to extend or replace DEC's various Programmed Data Processor ISAs...
processors developed and manufactured by Digital Equipment Corporation
Digital Equipment Corporation
Digital Equipment Corporation was a major American company in the computer industry and a leading vendor of computer systems, software and peripherals from the 1960s to the 1990s...
. It ran under the VAX/VMS operating system and produced object files suitable for the VAX/VMS linker. The Macro-32 assembler (and the linker) were bundled with the operating system.
With the advent of the 64-bit Alpha AXP chip, VAX Macro essentially became VMS Macro. Macro-32 was supported on the Alpha architecture, but because the Alpha used a different instruction set, the Macro-32 assembly language no longer mapped to the native instruction set. Macro-32 under the Alpha architecture was actually implemented then as a compiler, compiling VAX assembly language into Alpha instructions. Unlike most compilers, however, Macro-32 for Alpha performed no optimization, retaining as much as possible the programmer's direct control over the generated code.
The Alpha AXP chips introduced to the VMS world then the latest progression of the VMS Macro language, supporting the underlying RISC instruction set, and was called Macro-64.
A compiler from Macro-32 is available for Intel Itanium architecture A significant part of OpenVMS is written with Macro-32.