It deals with macroprocessing, augmentation, file inclusion. A generalpurpose macro processor or general purpose preprocessor is a macro processor. A preprocessor may include header files into the program text. It can also include macro processing, file inclusion and language extensions.
Jan 21, 2017 compiler design lecture 1 introduction and various phases of compiler duration. The amount and kind of processing done depends on the nature of the preprocessor. The macro preprocessor accepts an assembly program containing definitions and calls and translates it into an assembly program which does not contain any macro definitions and calls. Depending on the compiler, the preprocessor may be a separate program or it may be integrated into the compiler itself. Analysis phase known as the frontend of the compiler, the analysis phase of the compiler reads the source program, divides it into core parts, and then checks for lexical, grammar, and syntax errors. Hence, the macro facility is a preprocessor, which interprets all macro calls into assembly code prior to passing the expanded code. Algorithms applications 5 arithmetic operations 2 array 8 basics 27 compiler design 1 control statements 4 conversion functions 1 data structures 12 data type 1 date functions 1 file 36 keywords 1 loops 1 math functions 30 math snippets 43 memory management 3 misc 4 networking 4 operators 6 pointers 17 string functions 30 string snippets 29.
Compiler design 10 a compiler can broadly be divided into two phases based on the way they compile. Macro definitions are typically located at the start of a program. The title page means, for a printed book, the title page itself, plus such following. A preprocessor, generally considered as a part of compiler, is a tool that produces input for compilers. It makes no provision for either the library or the preprocessor. A generalpurpose macro processor or general purpose preprocessor is a macro processor that is not tied to or integrated with a particular language or piece of software a macro processor is a program that copies a stream of text from one place to another, making a systematic set of replacements as it does so. The program form output by the macro preprocessor can be handed over to an assembler to obtain the target program. A compiler design is carried out in the context of a particular language machine. Basics of compiler design pdf 319p this book covers the following topics related to compiler design.
If the parameter of the string literal requires an escape sequence like before a double quote it will automatically be inserted by the preprocessor. Modern versions of the gnu assembler have macro facilities. This book is based upon many compiler projects and upon the lectures given by the. These preprocessor attempts to add capabilities to the language by certain amounts to buildin macro compiler compiler is a translator program that translates a program written in hll the. Generally it doesnt come as a separate program but as a bundle to either assembler or compiler note. Language processing system translates the high level language to machine level language. In this preprocessor documentation, only the term macro is used. Preprocessor directives are removed, include files are included, definitions are replaced, not defined areas are removed and macros are expanded. While you do not need to use the preprocessor during normal compilation, you may find the list file helpful for debugging purposes. What is hideset in a c compilers preprocessor implementation. C has an integrated preprocessor that operates at the front end of its single pass algorithm.
This preprocessor takes the description of the semantics of a language i. This technique is called preprocessor and the process is called preprocessing. All code discussed in this article is known to work on antlr2. Including all the files from library that our program needs. August 20, 2010 isbn 9788799315406 compiler principl. The comments are replaced with a single space in the. The following table lists the macro names predefined by the.
These macros provide information about toolchain version numbers and compiler options. So below print statement will give us the same result. There are four entities involved in the compilation process. Preprocessing is the first step of the language processing system. C programmingpreprocessor directives and macros wikibooks.
Chapter 3b macro and macro preprocessordesign of macro prepropcessor 1. In many c implementations, it is a separate program invoked by the compiler as the first part of translation. It deals with macro processing, augmentation, language extension, etc. The fact that gcc does not describe the predefined macros in its compiler manual is an exception. A preprocessor is a system software a computer program that is designed to run on computers hardware and application programs. The comments are replaced with a single space in the translation phase, which happens prior to the. What is the function of the preprocessor, compiler, loader. When the name of a macro is recognized in the program source text, or in the arguments of certain other preprocessor commands, its treated as a call to that macro. The c preprocessor is not a part of the compiler, but is a separate step in the compilation process.
Free compiler design books download ebooks online textbooks. A macro processor is a program that copies a stream of text from one place to another, making a systematic set of replacements as it does so. Print this line will be converted to string by preprocessor. You will see the output with the code having no comments. For illustration purposes, we will construct a compiler for a simple imperative programming language called simple. The output of the c preprocessor is then fed to the c compiler proper. It expands macros in parts of some directives that arent skipped as part of a conditional compilation. Please dont confuse macro processor with micro processor, remember. The c99 specification handles this explicity, though. Macro processor is a program that lets you define the code that is reused many times giving it a specific macro name and reuse the code by just writing the macro name only.
An interpreter is like compiler which translates highlevel language into lowlevel machine language. The compiler proper consumes the clean output of the preprocessor. A preprocessor may allow a user to define macros that are short hands for longer constructs. Only the preprocessor sees these directive lines since it deletes them from the code stream after processing them. The output is said to be a preprocessed form of the input data, which is often used by some subsequent programs like compilers. The preprocessor is a part of the compiler which performs preliminary operations conditionally compiling code. In computer science, a preprocessor is a program that processes its input data to produce output that is used as input to another program. In addition to the basic capability of building targets from dependents, gnu make includes many features that make it easy for you to express the dependencies and rules for building a. Aug 04, 2016 chapter 3b macro and macro preprocessor design of macro prepropcessor 1. Macro processors are often embedded in other programs, such as assemblers and compilers. Preprocessors typically do macro substitutions, strip comments from compiler. Sometimes they are standalone programs that can be used to process any kind of text. Aug 20, 2010 ebooks basic of compiler design first published 2000 this edition.
Chapter 3b macro and macro preprocessordesign of macro. The macro name is replaced by a copy of the macro body. Preprocessor news newspapers books scholar jstor february 20 learn how and when to remove this template message. More details can be found in compilers, principles, techniques, and tools by aho, sethi, and ullman cse 401 book and appendix a of computer organization and design by patterson and hennesey cse 378 book compiling a program when you type cc at the command line a lot of stuff happens.
The command given above directs the compiler to include the header file standard inputoutput header file from c standard library in this program. The preprocessor provides the ability for the inclusion of header files, macro expansions, conditional compilation, and line control in many c implementations, it is a separate program invoked by the compiler as the first part of translation. Lexical analysis, syntax analysis, interpretation, type checking, intermediatecode generation, machinecode generation, register allocation, function calls, analysis and optimisation, memory management and bootstrapping a compiler. You should have some familiarity with antlr and the concept of topdown recursive descent parsers.
It is called a macro processor because it allows you to define macros, which are brief abbreviations for longer constructs the c preprocessor provides four separate facilities that you can use as you see fit. A macro facility is used to interpret macro definitions and expand each macro call as it occurs with the requisite pattern of assembly language statements, providing expanded source code ready for the assembler. This macro expands to the name of the main input file, in the form of a c string constant. At the very least you need to understand it and the way header files are combined with code files to create the document that is submitted to the compiler. Compiler design lecture 1 introduction and various phases of compiler duration. The c preprocessor is a macro processor that is used automatically by the c compiler to transform your program before actual compilation. In computer science, a preprocessor is a program that processes its input data to produce. Replaces trigraph sequences joins any line with the backslash character into single line divide program into set of tokens expand macroes remove comments and replace it by single space represent the escape sequence by. It is called a macro processor because it allows you to define macros, which are brief abbreviations for longer constructs. Standard input is used to denote input from keyboard and standard output is used to. Gate lectures by ravindrababu ravula 1,536,167 views. The instructions that the preprocessor parses are called directives and come in two forms. In the preceding example, the preprocessor did the macro expansion, and as a part of it, the preprocessor simply replaced the macros name with its value.
M4 and the htm4l macros work in a very similar way. Analysis phase known as the frontend of the compiler, the analysis phase of the compiler reads the source. The code in code box 12 has a valid c syntax, and now the compiler can proceed and compile it. The gnu make utility in linux comes to your rescue by reading and interpreting a makefile. Compiler construction tools, parser generators, scanner generators, syntax. The preprocessor is either a separate program invoked by the compiler or part of the compiler itself. It performs intermediate operations that modify the original source code and internal compiler options before the compiler tries to compile the resulting source code. This is the source file that was specified on the command line of the preprocessor or c compiler. Introduction of compiler design compiler construction tools three address code in compiler aishwaryaagarwal2. A macro prototype statement one or more model statements macro preprocessor statements the macro prototype statement declares the name of a macro and the names and kinds of its parameters. This book presents the subject of compiler design in a way thats. In addition to the basic capability of building targets from dependents, gnu make includes many features that make it easy for you to express the dependencies and rules for building a target from its dependents. A macro prototype statement one or more model statements macro preprocessor statements the macro prototype statement declares the name of a macro and the names and kinds of.
Preprocessor will ignore the spaces before or after the macro argument. A preprocessor is a translator whose source language is an extended form of some highlevel language and whose object language is the standard form of the highlevel language. The preprocessor provides the ability for the inclusion of header files, macro expansions, conditional compilation, and line control. The macro implementation of snobol4, griswold 1972 although highly successful. It performs preprocessing of the high level language hll. It contains well written, well thought and well explained computer science and programming articles, quizzes and practicecompetitive programmingcompany interview questions. These preprocessor attempts to add capabilities to the language by certain amounts to build in macro compiler compiler is a translator program that translates a program written in hll the. A preprocessor may allow a user to define macros that are short. This document briefly describes what happens when you compiler and run a program. This is mostly because the book is 22 years old, and predates electronic books. Templates remove the need for a macros by providing a safer, more efficient and specializable even i dont think thats a real word way of implementing code for multiple types. Unfortunately, the original ansi c specification specifically excludes any preprocessor features in section 4 this specification describes only the c language.
Program that processes or analyzes the source code file before given to the compiler tasks performed by preprocessor. Macros refers some specific set of instructions that can be used one after another in a same program. It might also strip comments and unnecessary whitespace. Sunita m dol aher, assistant professor, computer science and engineering department, walchand institute of technology, solapur, maharashtra 2. The c prepro cessor pro vides four separate facilities that y ou can use as y ou see t. The c preprocessor is a macro processor that is used automatically by the c compiler to transform your program before actual compilation proprocessor direcives are executed before compilation. Compiler design introduction lecture 1system programming. Introduction to compilers and language design copyright. Variables or macros in the gnu make utility dummies. The c preprocessor gcc, the gnu compiler collection.