Design And Implementation Of Cross Compiler Based On LLVM

With the rapid development of microprocessor technology, the performance of the processor is mostly influenced by a variety of factors. The quality of the compiler plays a critical role in processor. Some microprocessors have no installation of compile system. On the one hand, its storage space may be too small to run the compiler. On the other hand, it is due to the cost of redesign and the implements for a new compiler will take a high costs and a long time in development, besides sometimes it has to face a high risk of patent. For these reasons, microprocessor vendors often do not easily update a new type compiler for a specific CPU, but to reuse some existing portable open source compiler framework to build a cross compiler instead.Based on the open source LLVM compiler architecture and Power PC970 processor, the paper uses LLVM reusable characteristic to design and realize a cross compiler. The function is mainly to convert high-level language program into Power PC970 target machine assembly code. The cross compiler achieves complete compiler tool chain Power PC970 processor.All the work of this paper is to design and implement a cross compiler based on LLVM. Cross compiler consists of three parts, front end by a high-level language, intermediate code optimizer, and target processor code generator. Under the framework existing, LLVM is developed by modifying and optimizing both in the front part and the middle part of the optimization. This paper is focused on achieving the transplant work for Power PC970 in cross compiler backend transplant. Through introducing the framework and functions of LLVM compiler system, then according to the requirements analysis, this paper designs a type of cross compiler under the framework, and later realize this cross compiler on the basis of relevant design meterials. Finally, the cross compiler is estimated whether its functions implement succesessfully by testing and verification.To achieve this cross compiler, not only can the tool chain get fully improved and expand the Power PC horizons in applications, but also it is able to make the Power PC970 benefiting from the LLVM excellent characteristics, and enhance the performance of the platform as far as possible in the compiled hierarchy.