IBM Basic assembly language and successors: Difference between revisions

Revision as of 05:28, 20 January 2025

Revision as of 20:55, 2 February 2025

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==General characteristics==

As it is an [[assembly language]], BAL uses the native [[instruction set]] of the IBM mainframe architecture on which it runs, [[IBM System/360|System/360]]., just as the successors to BAL use the native instruction sets of the IBM mainframe architectures on which they run, including [[IBM System/360|System/360]], [[IBM System/370|System/370]], [[IBM System/370-XA|System/370-XA]], [[IBM ESA/370|ESA/370]], [[IBM ESA/390|ESA/390]], and [[z/Architecture]].

The successors to BAL use the native instruction sets of the IBM mainframe architectures on which they run, including [[IBM System/360|System/360]], [[IBM System/370|System/370]], [[IBM System/370-XA|System/370-XA]], [[IBM ESA/370|ESA/370]], [[IBM ESA/390|ESA/390]], and [[z/Architecture]].

The simplicity of machine instructions means that the [[source code]] of a program written in assembler will usually be much longer than an equivalent program in, say, [[COBOL]] or [[Fortran]]. In the past, the speed of hand-coded assembler programs was often felt to make up for this drawback, but with the advent of optimizing compilers, [[C (programming language)|C]] for the mainframe, and other advances, assembler has lost much of its appeal. IBM continues to upgrade the assembler, however, and it is still used when the need for speed or very fine control is paramount. However, all of the IBM successors to BAL have included a sophisticated macro facility that allows writing much more compact source code.