编译原理的源代码，涉及了编译原理的过程：中间代码生成，中间代码优化（常表达式优化，公共表达式优化，循环不变式优化），中间代码生成目标代码，目标代码的解释执行-compiler source code, the compiler principles involved in various processes : code generation and code optimization (regular expression optimization, public expression optimization, optimization loop invariant), intermediate code generated object code target code enforcement explained in detail