High-level assembler

Last updated

A high-level assembler in computing is an assembler for assembly language that incorporate features found in a high-level programming language.

The earliest high-level assembler was probably Burroughs' Executive Systems Problem Oriented Language (ESPOL) in about 1960, which provided an ALGOL-like syntax around explicitly-specified Burroughs B5000 machine instructions. This was followed by Niklaus Wirth's PL360 in 1968; this replicated the Burroughs facilities, with which he was familiar, on an IBM System/360. More recent high-level assemblers are Borland's Turbo Assembler (TASM), Netwide Assembler (NASM), Microsoft's Macro Assembler (MASM), IBM's High Level Assembler (HLASM) for z/Architecture systems, Alessandro Ghignola's Linoleum, X# used in Cosmos and Ziron.[ citation needed ]

High-level assemblers typically provide instructions that directly assemble one-to-one into low-level machine code as in any assembler, plus control statements such as IF, WHILE, REPEAT...UNTIL, and FOR, macros, and other enhancements. This allows the use of high-level control statement abstractions wherever maximal speed or minimal space is not essential; low-level statements that assemble directly to machine code can be used to produce the fastest or shortest code. The end result is assembly source code that is far more readable than standard assembly code while preserving the efficiency inherent with using assembly language.

High-level assemblers generally provide information-hiding facilities and the ability to call functions and procedures using a high-level-like syntax (i.e., the assembler automatically produces code to push parameters on the call stack rather than the programmer having to manually write the code to do this).

High-level assemblers also provide data abstractions normally found in high-level languages. Examples include: data structures, unions, classes, and sets. Some high-level assemblers (e.g., TASM and High Level Assembly (HLA)) support object-oriented programming.

Related Research Articles

Assembly language Low-level programming language

In computer programming, assembly language, often abbreviated asm, is any low-level programming language in which there is a very strong correspondence between the instructions in the language and the architecture's machine code instructions. Because assembly depends on the machine code instructions, every assembly language is designed for exactly one specific computer architecture. Assembly language may also be called symbolic machine code.

In computing, a compiler is a computer program that translates computer code written in one programming language into another language. The name "compiler" is primarily used for programs that translate source code from a high-level programming language to a lower level language to create an executable program.

Macro (computer science) In computer science, a concise representation of a pattern

A macro in computer science is a rule or pattern that specifies how a certain input should be mapped to a replacement output. Applying a macro to an input is macro expansion. The input and output may be a sequence of lexical tokens or characters, or a syntax tree. Character macros are supported in software applications to make it easy to invoke common command sequences. Token and tree macros are supported in some programming languages to enable code reuse or to extend the language, sometimes for domain-specific languages.

System call Mechanism used by an application program to request service from the kernel of the operating system

In computing, a system call is the programmatic way in which a computer program requests a service from the kernel of the operating system on which it is executed. This may include hardware-related services, creation and execution of new processes, and communication with integral kernel services such as process scheduling. System calls provide an essential interface between a process and the operating system.

FASM Open source assembler for x86 processors

FASM is an assembler for x86 processors. It supports Intel-style assembly language on the IA-32 and x86-64 computer architectures. It claims high speed, size optimizations, operating system (OS) portability, and macro abilities. It is a low-level assembler and intentionally uses very few command-line options. It is free and open-source software.

In computer science, a high-level programming language is a programming language with strong abstraction from the details of the computer. In contrast to low-level programming languages, it may use natural language elements, be easier to use, or may automate significant areas of computing systems, making the process of developing a program simpler and more understandable than when using a lower-level language. The amount of abstraction provided defines how "high-level" a programming language is.

A low-level programming language is a programming language that provides little or no abstraction from a computer's instruction set architecture—commands or functions in the language map that are structurally similar to processor's instructions. Generally, this refers to either machine code or assembly language. Because of the low abstraction between the language and machine language, low-level languages are sometimes described as being "close to the hardware". Programs written in low-level languages tend to be relatively non-portable, due to being optimized for a certain type of system architecture.

The Burroughs Large Systems Group produced a family of large 48-bit mainframes using stack machine instruction sets with dense syllables. The first machine in the family was the B5000 in 1961. It was optimized for compiling ALGOL 60 programs extremely well, using single-pass compilers. It evolved into the B5500. Subsequent major redesigns include the B6500/B6700 line and its successors, as well as the separate B8500 line.

A system programming language is a programming language used for system programming; such languages are designed for writing system software, which usually requires different development approaches when compared with application software. Edsger Dijkstra refers to these language as Machine Oriented High Order Languages, or mohol.

Disk Operating System/360, also DOS/360, or simply DOS, is the discontinued first member of a sequence of operating systems for IBM System/360, System/370 and later mainframes. It was announced by IBM on the last day of 1964, and it was first delivered in June 1966. In its time, DOS/360 was the most widely used operating system in the world.

High Level Assembly (HLA) is a high-level assembly language developed by Randall Hyde. It allows the use of higher-level language constructs to aid both beginners and advanced assembly developers. It fully supports advanced data types and object-oriented programming. It uses a syntax loosely based on several high-level programming languages (HLLs), such as Pascal, Ada, Modula-2, and C++, to allow creating readable assembly language programs, and to allow HLL programmers to learn HLA as fast as possible.

The history of programming languages spans from documentation of early mechanical computers to modern tools for software development. Early programming languages were highly specialized, relying on mathematical notation and similarly obscure syntax. Throughout the 20th century, research in compiler theory led to the creation of high-level programming languages, which use a more accessible syntax to communicate instructions.

The Microsoft Macro Assembler (MASM) is an x86 assembler that uses the Intel syntax for MS-DOS and Microsoft Windows. Beginning with MASM 8.0, there are two versions of the assembler: One for 16-bit & 32-bit assembly sources, and another (ML64) for 64-bit sources only.

Work Flow Language, or WFL ("wiffle") is the process control language for the Burroughs large systems, including the Unisys ClearPath/MCP series, and their operating system Master Control Program. Developed soon after the B5000 in 1961, WFL is the ClearPath equivalent of the Job Control Language (JCL) on IBM mainframes and the shell scripts of Unix-like operating systems. Unlike JCL, WFL is a high-level structured language complete with subroutines with arguments and high-level program control flow instructions. WFL programs are compiled to binary executables like any other MCP subject.

Autocoder is any of a group of assemblers for a number of IBM computers of the 1950s and 1960s. The first Autocoders appear to have been the earliest assemblers to provide a macro facility.

This is a list of assemblers: computer programs that translate assembly language source code into binary programs. Some assemblers are components of a compiler system for a high level language and may have limited or no usable functionality outside of the compiler system. Some assemblers are hosted on the target processor and operating system, while other assemblers (cross-assemblers) may run under an unrelated operating system or processor. For example, assemblers for embedded systems are not usually hosted on the target system since it would not have the storage and terminal I/O to permit entry of a program from a keyboard. An assembler may have a single target processor or may have options to support multiple processor types. Very simple assemblers may lack features, such as macros, present in more powerful versions.

Basic Assembly Language (BAL) is the commonly used term for a low-level programming language used on IBM System/360 and successor mainframes. Originally, "Basic Assembly Language" applied only to an extremely restricted dialect designed to run under control of IBM Basic Programming Support (BPS/360) on systems with only 8 KB of main memory, and only a card reader, a card punch, and a printer for input/output — thus the word "Basic". However, the full name and the initialism "BAL" almost immediately attached themselves in popular use to all assembly-language dialects on the System/360 and its descendants. BAL for BPS/360 was introduced with the System/360 in 1964.

PL360 is a system programming language designed by Niklaus Wirth and written by Wirth, Joseph W. Wells Jr., and Edwin Satterthwaite Jr. for the IBM System/360 computer at Stanford University. A description of PL360 was published in early 1968, although the implementation was probably completed before Wirth left Stanford in 1967.

In computing, a compiler is a computer program that transforms source code written in a programming language or computer language, into another computer language. The most common reason for transforming source code is to create an executable program.

References