History of compiler construction A diagram of the operation of a typical multi-language, multi-target compiler Theoretical computing concepts developed by scientists, mathematicians, and engineers formed the basis of digital modern computing development during World War II.
Compiler Basics, Part 2: Building the Scanner Have you ever thought of writing your own compiler? There are a number of good reasons to do this. It can solve problems and produce abstractions that can simplify some previously complex procedures.
However, there are just as many reasons not to write your own compiler. Good compilers already exist. When I first started exploring compiler development, I was frustrated that the available material tended toward the high end.
Most programmers can find endless entertainment writing a compiler for a simple Basic-style dialect. At the end of the day, you should have enough experience to write useful compilers that can replace poor-performing interpreters in a number of applications.
The first thing I need is a way to read the original source code. I need a simple abstraction to load the contents of a text file into memory. A memory-mapped file is often the best choice. Of course, I want to hide the details away from my main program.
Perhaps something like this: Begin ; Scanner scanner file. I should be able to use the explicit Boolean operator of the class to check for failure. Because this will be implemented with the Windows API, the main function could even use the GetLastError function to determine the specific reason for the failure.
The FileMap class should provide a Size method, as well as Begin and End methods, for convenient access to the file contents.
That would avoid a lot of boilerplate code. Now, the particular mechanics. A memory-mapped file involves three objects or resources. First, you need to create the file object representing the file on disk. Then, you need to use the resulting file handle to create a file mapping object.
Next, you need to map a view of the file using the file mapping handle. Although the API makes it appear as if the view is just a pointer, that pointer is really a resource that needs managing, just like the file and file mapping objects.Writing a lexer in C++. Ask Question.
up vote 14 down vote favorite. 7. and the author of the Epoch compiler explains how he got a x speed-up by intensive profiling and investigation in how Qi works in an article.
A lexer generator takes a lexical specification, which is a list of rules (regular-expression-token pairs), and. Task of Lexical Analysis is to read the input characters and produce as output a sequence of tokens that the parser uses for syntax analysis.
Lexical Analyzer is First Phase Of Compiler. Input to Lexical Analyzer is “ Source Code “. Lexical Analysis • Read source program and produce a list of tokens (“linear” analysis) Yale University Lexical Analysis: Page 9 of 40 Lexical Specification • Using regular expressions to specify tokens keyword = begin | end | if | then | else identifier = letter (letter | digit | underscore)*.
Lexical Analysis • Read source program and produce a list of tokens (“linear” analysis) • The lexical structure is specified using regular expressions • Other secondary tasks: (1) get rid of white spaces (e.g., \t,\n,\sp) and comments CS COMPILERS AND INTERPRETERS C.
Lexical Analysis • Read source program and produce a list of tokens • First, write down the lexical specification (how each token is defined?) using regular expression to specify the lexical structure: identifier = letter (letter CS COMPILERS AND INTERPRETERS C. ii) Use the associative and commutative laws to modify the block to use the fewest possible number of Compiler ConstructionCredit Hours: 3(3, 0) Recommended Book: Compliers; Principles, Techniques, and Tools by Alfred V.
Aho, Ravi Sethi, Jerrey D. Ullman Course Outlines: Unit No. 1 Introduction to Compiling Compliers, analysis of the source.