2110316  Programming Languages Principles 3(3-0-6)

2st semester, Jan 2020

Prabhas Chongstitvatana

official course description

Principal lecturer: Prabhas

This course is divided into three equal parts.

1) Programming Language concepts, Prabhas and Vishnu
2) Non-imperative programming language, Vishnu
3) Language and implementation, Prabhas

The goal of this course is to make you understand computer languages you use. To make you appreciate diversity of ideas in programming and prepare you for new programming methods and paradigms. Theoretical foundations will be presented. You will know properties of language, not just syntax. Moreover, you will recognize the cost of presenting an abstract view of machines and understand trade-offs in programming language design.  

Each part will be taught separately and independently. It is logical that the assessment will also be arranged according to this structure. There is no midterm exam (besides whatever assess by the lecturer at that time) and the final exam will contain all materials taught in the course.

Assessment

each part  20%  by 3  =  60%
final exam                      40%

Announcement

. . .

Study Plan

each section lasts 4 weeks.
an in-class work will be handed out each week.
no midterm exam.
at the end of each section, one quiz will be issued.

Lectures

1. Theory of programming language

Evolution of programming language
Names, scope and binding
Control flow
Data types
Control abstraction
Data abstraction and object

2. Non-Imperative programming

see Aj Vishnu lecture

3. Language and implementation

This part concerns a compiler for a programming language. There are two aspects of learning this part: theory and practice.  The theory will be given in the lectures.  The practice is carried on as classwork. To teach effectively I choose to design a toy language and implement its compiler. You will be studying actual compilers and modify them.

1  structure of a compiler
Intro to Compiler  Supplement: Cross compiler
lexical analyser      Scanner   

2  grammar

Demonstrate the actual compiler of this course
Context Free Grammar   
Example of writing a grammar to specify a language
Recursive programming with List    extra exercises 

3  parsing      

Parsing    top-down parsing  
How to compute First and Follow set  (by Prof. Kamin at UIUC)
LL parser at Wiki 
    
4  actual parser   
        a recursive descent parser for a simple language
        a parser with building parse tree   
        write a parser from a parsing table
        LL1 parser of grammar from lecture parsing page 25 (LL1-parser.zip)  (slide)  

   code generator
        Code Generation     Som v2.0 virtual machine   S-code
        Recursive evaluator, an interpreter of Rz parse tree    eval3.c   

   summary of compiler part

Videos (part compiler)

Introduction to compiler    https://youtu.be/x-M-FO_L1ZI
Scanner part 1/3: Regular Expression   https://youtu.be/Ut1yfhqvHYw
Scanner part 2/3: Convert Reg Ex to Finite Automata     https://youtu.be/LKuzE-XAEQo
Scanner part 3/3: Demo how to run a scanner (code in C)   https://youtu.be/LD0ukaiIZtY
Grammar part 1/3:   Grammar, derivation   https://youtu.be/KmUpDnsVW4I
Grammar part 2/3:   Writing grammar to cover a language  https://youtu.be/5u81CE-f0ew
Grammar part 3/3:   Ambiguous grammar   https://youtu.be/xLsJWVFuLG8
Write a recursive program part 1/2: 
   Define a language and write recursive programs  https://youtu.be/PZRgH8MRn8Q
Write a recursive program part 2/2: 
   Demonstrate how to actually compile and run those programs  https://youtu.be/Ue2Q8ZTzVN8
Parsing part 1/4:   Parser, recursive descent parser    https://youtu.be/XwMAXnigEoU
Parsing part  2/4:   Writing a recursive descent parser (for ASM language)   https://youtu.be/-PmvUE2yR08
Parsing part  3/4:  LL(1), simulate stack, first set    https://youtu.be/bQL0CuMqc3M
Parsing part  4/4:  LL(1), follow set, parsing table, remove left recursion    https://youtu.be/diBBHyKZpgg
Parsing (bonus):  LL(1) write a parser from parsing table   https://youtu.be/x58vRak89BQ
Code generation part 1/3:  Parse tree  https://youtu.be/1eJmVM-eL8A
Code generation part 2/3:  Abstract interpreter   https://youtu.be/pvZlecsItdg
Code generation part 3/3:  Machine instruction  https://youtu.be/XX0fW24M55A

Reference Text

-- Jaruloj Chongstitvatana, Programming Languages Principles and Processing, (local copy) Dept. of Math and CS, Chulalongkorn, 2017. (main text)
-- Aho, Sethi, Ullman, Compilers: Principles, Techniques, and Tools. Addison-Wesley, latest edition.
-- Louden, K.C., Compiler Construction: Principles and Practice. PWS Publishing Co., 1997.

The main text is Jaruloj.  It covers larger topics than required in this class.  Our presentation follows this textbook.  Aho,Sethi, Ullman is the standard textbook on compiler. It has been used in more than 100 universities in North America.  It is a bit difficult to read as it contains a lot of theory.   Louden is much easier to read.   The latest edition is 1997, you can find it in Amazon.

Extra reading

Tools

Recommended free C compiler for Windows lcc-win32 . (for Windows 7, 8, 8.1 and 10).  Please also download and install "User Manual". You need it to look up the library function of this C.  (for OS X you need xcode, also free).

See my Rz language homepage
the compiler  package with code generator  rz36-3.zip
lexical analyser  (lex-35-3.zip,   extract from rz35-3 package)
Rz compiler on the web  (by Kamoluk Suksen)
New example of a recursive descent parser for a simple assembly language   asm-summer-2.zip
LL1 parser from lecture parsing page 25  LL1-parser.zip
the updated package  LL1-parser-2.zip  works on both Windows 10 and MacOS (I use xcode to compile on Mac). The executable file for Mac is used this way, on Mac opens a terminal: 

$ ./xparser test.txt

To practice recursive programming in the lecture, you need this library  ailib.zip  (in C).
Example of building parse tree   ex-parse-tree-2.zip  (clean up)

How to use the compiler

Use rz36  to compile and run your programs.   Here is what a session looks like.  Go to rz36/test directory  (that you unzip the package to).  There are three executable files:   rz36.exe, as21.exe, sim21.exe  .  Try to compile "fac.txt".  It is shown here:

// factorial

fac(n)
  if( n == 0 ) return 1
  else return n * fac(n-1)


main()
  print(fac(6))

 
    Here is the command line and the output at the screen:

D:\rz36\test>rz36 fac.txt
fac
main
(fun main (print (call fac 6 )))
(fun fac (else (== #1 0 )(return 1 )(return (* #1 (call fac (- #1 1 ))))))


    ...

   
You will get the assembly file as an output file.  Then, use as21.exe to "assemble" (change assembly file into object code file).  You can "run" it under s2 simulator (execute machine code) s21.exe.

D:\rz36\test>sim21 fac.obj
720


That's it.  Enjoy!

Prabhas Chongstitvatana
contact address:   prabhas at chula dot ac dot th     
office   room 18-13  Engineering Building 4, floor 18.  tel 02-2186982
research lab:  Intelligent Systems,  floor 20.

Last update  26 Apr 2021