What a High Level Assembler can do for your business

IBM® High Level Assembler (HLASM) and Toolkit Feature is a flexible development solution for all Assembler Language applications. The assembler and optional toolkit improves programmer productivity and simplifies program development and maintenance. HLASM provides all the proven facilities found in earlier assemblers and includes many new facilities. It helps you develop programs and subroutines for functions not typically provided by other symbolic languages, such as COBOL, FORTRAN, and PL/I. High Level Assembler provides extensions to the basic assembler language, and the macro and conditional assembly language, including external function calls and built-in functions. The optional High Level Assembler Toolkit Feature is a powerful and flexible set of tools that enhances application recovery and development.



Enhanced usability with warning-suppression option.


Simplified tool integration with improved SYSADATA record layouts.


Cross-system compatibility assisted by ASCII constants.


Simplified macro coding with longer macro arguments and string variables.

IBM High Level Assembler and Toolkit features

  • Changed Assembler instructions
  • Unified Opcode table
  • Mnemonic tagging
  • Programming and diagnostic aids
  • Macro language extensions
  • Conditional assembly extensions