Compiling Pascal

This part describes the actual project. After a chapter explaining why Pascal was chosen as the source language, there will be several chapters about how I compiled Pascal source programs to Java class files and the problems I had. I will conclude this document with a chapter about some of the things I did not implement and how they should be done and a chapter containing some final words about the project including what can be concluded from all this.

All throughout the project I used the Java compiler javac and the Java Virtual Machine java from the Java Developer's Kit. In the beginning I used JDK1.0.2 and later I used JDK1.1.2.

• The Project
  • Translating EM to Java Bytecode
  • C as Source Language
  • Pascal as Source Language
  • Problems and Solutions
• Starting Out
  • How to Store a Class File
  • Datastructures to Hold the Class File
• The Empty Program
  • Initial constant_pool[] Entries
  • <init>
  • main
  • Fit it in the Compiler
• Declarations
  • Variable and Constant Declarations
    • Variables and Constants as ``Normal'' Java Fields
    • Variables and Constants as Objects or Arrays
    • The Problem with Local Variables
  • Procedure and Function Declarations
    • How to Compile a Procedure or Function
    • Parameters
• Statements
  • Maintaining the Size of the Operand Stack
  • Expressions
    • Constant Values
    • Variable Values
    • Unary Operators
    • Binary Operators
      • Arithmetic operators
      • Comparison Operators
      • Boolean Operators
  • Assignments
  • Procedure and Function Calls
  • write and writeln Statements
  • Control Statements
    • If Then Else
    • Other Conditional Statements
      • While
      • Repeat
      • For
      • Case
  • Function Returns
• Things Left To Do
  • Records
  • Pointers
  • goto Statements
• Final Remarks
  • Conclusion
  • Personal Experience
  • Acknowledgments
• An Example Program
  • Pascal Source Code
  • Java Class File
    • jdisco Output
    • D-Java Output