匯編器在微處理器的驗證和應(yīng)用中舉足輕重，如何設(shè)計通用的匯編器一直是研究的
熱點之一。本文提出了一種開放式的匯編器系統(tǒng)設(shè)計思想，在匯編語言與機器語言間插入中間代碼CMDL（code mapping description language）語言，打破匯編語言與機器語言的直接映射關(guān)系，由此建立起一套描述匯編語言與機器語言的開放式映射體系。基于此開放式映射體系開發(fā)了一套匯編器系統(tǒng)，具有較高層次上的通用性和可移植性。
【關(guān)鍵詞】指令集，CMDL，匯編器，開放式

Design of Retargetable Assembler System Liu Ling Feng Wen Nan Wang Ying Chun Jiang An Ping Ji Li Jiu IME of Peking University, 100871
【摘要】An assembler plays a very important role in the field of microprocessor verifications and applications, thus how to build a retargetable assembler system has been a hotspot in this field for long time. This paper presents a new method about the retargetable assembler system design.It provides a kind of language CMDL, code mapping description language. During the process of assembling, assembler languages are firstly translated to CMDL, and then mapped to the machine codes. In an other word, CMDL is inserted between assembler languages and machine codes during the translation procedure. As a medium code, CMDL has a lot of features, such as high extraction, strong descript capabilities. It can describe almost all attributes of assembler languages. By breaking the direct mapping relationship between assembler languages and machine codes, the complexities of machine codes are hided to the users, therefore, the new retargetable assembler system has higher retargetable level by converting the mapping from assembler languages and machine codes to assembler languages and CMDL, and implementation
of it becomes easier. Based on the new mapping system structure, a retargetable assembler
system is developed. It proved the whole system has good retargetability and implantability.
【關(guān)鍵詞】instruction set, symbol table, assembler, lexical analysis, retargetability