Design And Implementation Of The ASM05 Assembler

The development of assembler has a long history. The first assembler appeared in 1940. Assembler is one essential part of compiler tool chain of a computer. Now, the theory of assembler is very ripe. Today, chip industry is developing fast and much more people are engaged in the research of embedded system processor. The traditional theory of assembler still plays an important role because many new assemblers should be implemented for many new embedded system processors. Though the traditional theory of assembler can give effective direction to design and development of assembler, it doesn't mention anything about the maintenance of assembler. This is a blind spot in the commercial age because the assembler, as a production, must be improved according to the consumer's advice from time to time. For this, this paper presents new assembler architecture, a feature-extensible assembler architecture, which completes the traditional theory on maintenance of assembler. Such architecture is easy to maintain. It is easy to modify the function of the assembler without make great change on the architecture if the assembler uses such architecture. Furthermore, this paper uses such architecture to implement the ASM05 assembler and validates the efficiency of such architecture on maintenance by adding MACRO and INCLUDES directives to ASM05 assembler. These two functions, MACRO and INCLUDE, were not considered when designing the ASM05 assembler at first. Besides, this paper presents the detail of the implementation of ASM05 assembler.