VAX MACRO

{{Short description|Computer assembly language}}

{{Infobox programming language

| name = VAX MACRO

| paradigms = non-structured, imperative

| family = assembly language

| designer =

| developer = Digital Equipment Corporation

| released = {{Start date and age|1977}}

| typing = Untyped

| scope = Lexical

| programming language = assembly language

| discontinued = Yes

| platform = VAX

| operating system = VMS

| influenced by = MACRO-11

| influenced = MACRO-64

| website =

}}

VAX MACRO is the computer assembly language implementing the VAX instruction set architecture for the OpenVMS operating system, originally released by Digital Equipment Corporation (DEC) in 1977.

The syntax, directives, macro language, and lexical substitution operators of VAX MACRO formerly appeared in MACRO-11, the assembler for the PDP-11 series of computers. The MACRO-32 assembler supported the VAX processors developed and manufactured by DEC. It ran under the VMS operating system and produced object files suitable for the VMS linker. The MACRO-32 assembler and linker were bundled with the operating system.

To port VMS to the DEC Alpha, VAX MACRO was implemented for the Alpha architecture. Since the Alpha used a different instruction set than the VAX, MACRO-32 was implemented as a compiler, compiling VAX assembly language into Alpha instructions.{{cite journal |last1=Kronenberg |first1=Nancy P. |last2=Benson |first2=Thomas R. |last3=Cardoza |first3=Wayne M. |last4=Jagannathan |first4=Ravindran |last5=Thomas |first5=Benjamin J. III |year=1992 |url=http://www.hpl.hp.com/hpjournal/dtj/vol4num4/vol4num4art7.pdf |title=Porting OpenVMS from VAX to Alpha AXP |journal=Digital Technical Journal |volume=4 |issue=4}}

The Alpha AXP chips have their own native instruction set architecture, the OpenVMS assembler for Alpha assembly code is named MACRO-64.{{cite web |url=https://vmssoftware.com/docs/VSI_PROGRAM_CONCEPTS_VOL_I.pdf |title=VSI OpenVMS Programming Concepts Manual |date=April 2020 |volume=1 |publisher=VMS Software Inc. |access-date=2020-10-07}}

A MACRO-32 compiler is also available for the Intel Itanium architecture,[http://h71000.www7.hp.com/wizard/wiz_9837.html?jumpid=reg_R1002_USEN HP OpenVMS ask the wizard – Macro32 Assemblers and Compilers? OpenVMS I64?] and for x86-64.{{cite web |url=http://vmssoftware.com/pdfs/State_of_the_Port_March2016.pdf |title=State of the Port to x86 |date=March 2016 |website=VMS Software Inc. |url-status=dead |archive-url=https://web.archive.org/web/20191029161159/http://vmssoftware.com/pdfs/State_of_the_Port_March2016.pdf |archive-date=2019-10-29}}