Introduction to compilation principles
The study of compilation principles is very important for understanding and designing programming languages, compilers and interpreters. It can not only improve the execution efficiency of the program, but also help developers better understand the operating mechanism of the program. Compilation principle is an important branch of computer science, which studies the design and implementation of compilers. For programmers who are engaged in compiler development, programming language design, or are interested in the principles of compilation, learning the principles of compilation is very helpful. For programmers who work primarily in application development, website development, or other fields, learning the principles of compilation may not be necessary. However, for those who wish to gain a deeper understanding of the principles behind programming languages and development tools, learning to understand compilation The principle has many benefits:
Learning the principles of compilation can help programmers better understand the working principles and grammatical structures of programming languages. Understanding compilation principles can help programmers better use and develop programming tools, such as compilers, interpreters, static analysis tools, etc. This helps you write more efficient and reliable code and take better advantage of the features and capabilities of your programming language. Understanding compilation principles can help programmers better understand how code behaves during compilation and execution. This is very helpful for debugging and troubleshooting, allowing problems to be located and fixed faster.
The languages we use in daily development are generally high-level syntax such as C++, JAVA, Python, JavaScript, etc., but computers can only recognize machine codes such as 0 and 1. So how are these high-level languages translated into 0, 1, etc. that can be recognized by machines?
The process of translating high-level languages into 0s and 1s that can be recognized by machines is mainly done through a compiler or interpreter.
Compilers and interpreters are tools used to convert high-level languages into machine language or directly execute high-level language programs. They differ in how they work and how they perform.
translater:
How it works: The compiler converts the entire high-level language program into the machine language of the target machine in one go. The working process of the compiler includes stages such as lexical analysis, syntax analysis, semantic analysis, intermediate code generation, code optimization and target code generation.
Execution method: The target code generated by the compiler can be executed directly on the target machine. The compiler converts a high-level language program into machine language only once, and then the target code can be executed repeatedly without having to translate it again.
Interpreter:
Working principle: The interpreter interprets and executes high-level language programs line by line. The working process of the interpreter includes stages of lexical analysis, syntax analysis, semantic analysis and interpretation execution.
Execution method: The interpreter interprets and executes the source code line by line during the execution process, converts high-level language instructions into machine instructions and executes them. The interpreter does not need to generate object code; the source code needs to be reinterpreted for each execution.
Learning the principles of compilation can help you better understand how compilers and interpreters work.
Compiler principles are a branch of computer science that mainly studies the design and implementation of compilers. A compiler is a program that converts high-level programming languages (such as C, C++, Java, etc.) into low-level machine language (such as binary code) that a computer can execute. The goal of compilation principles is to develop efficient, reliable, and optimizing compilers.
The main contents of the compilation principles course include:
Lexical Analysis: Divide the source code into lexical units (Tokens), such as identifiers, keywords, operators, etc.
Syntax Analysis: According to the grammatical rules of the programming language, lexical units are connected in series to form a syntax tree (Parse Tree) or an abstract syntax tree (AST).
Semantic Analysis: Static inspection of the syntax tree to verify whether the program conforms to the semantic rules of the language, such as type checking, scope checking, etc.
Intermediate Code Generation: Convert the abstract syntax tree into an intermediate representation between source code and target code, usually a three-address code, virtual machine instruction or similar form.
Optimization: Optimize intermediate code to improve program performance, reduce resource consumption, etc., such as constant folding, loop optimization, inlining, etc.
Target code generation (Code Generation): Convert optimized intermediate code into machine language or bytecode so that the computer can execute it.
The symbol table (Symbol Table) is a data structure used in the compiler to record information about various identifiers (variables, function names, etc.) in the program. It plays a connecting role in the compilation process. During the lexical analysis and syntax analysis stages, the compiler adds the encountered identifiers to the symbol table and records its attribute information, such as type, scope, etc. During the semantic analysis phase, the compiler can use the symbol table to perform operations such as identifier lookup and type checking. At the same time, the symbol table can also help the compiler detect semantic errors such as repeated definitions and undeclarations.
Error handling is a mechanism for handling errors when errors are encountered during compilation. The compiler will detect and report errors at various stages such as lexical analysis, syntax analysis, and semantic analysis. Errors can include syntax errors (such as missing semicolons, mismatched brackets, etc.), semantic errors (such as type mismatch, undeclared variables, etc.), and other errors related to the compilation process. Compilers need to design reasonable error handling strategies, such as printing error information, locating error locations, and giving suggested repairs, etc., to help developers find and solve problems as soon as possible.
Compiler Principles is an important professional course set up by the computer major. It is a required course for students in computer-related majors. It is also the foundation and core course for cultivating computer professionals in colleges and universities.
The following is a representation of a typical compilation process (although the compilation process is slightly different for different high-level languages):
Tip: If it is interpreted execution, the synthesis phase can be partially replaced with interpreted execution.
Interpretation and execution: Interpret and execute the syntax tree line by line, convert high-level language instructions into machine instructions and execute them. Interpret and execute the syntax tree line by line, convert high-level language instructions into machine instructions and execute them. The interpreter interprets and executes the source code line by line during execution without generating target code.
Introductory Notes on Compilation Principles https://zhuanlan.zhihu.com/p/130702001
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