Mini Compiler

Overview

This project involves the development of a simple compiler aimed at providing a practical understanding of compiler construction principles. The compiler is designed for a simple language specified by a given grammar. Its core functionality includes parsing input programs, generating an intermediate representation (IR), and executing the IR using a provided interpreter. The focus is on educational insights into compiler design rather than production-level application.

Features

• Grammar-Based Parsing: Implements a parser that adheres to a predefined grammar, ensuring accurate syntactical analysis of the input program.
• Intermediate Representation (IR) Generation: Transforms parsed input into an IR, represented as a linked list of instructions, facilitating subsequent execution phases.
• Execution via Interpretation: Utilizes a provided interpreter to execute the IR, enabling the evaluation of the program's logic without the need for assembly code generation.
• Support for Key Programming Constructs: Handles essential programming constructs, including variable declarations, assignment, conditional (if, while), iterative (for), and selection (switch) statements, as well as input/output operations.

Technical Details

• Language: The project is implemented in C++, taking advantage of its features for efficient data structure manipulation and control flow management.
• Input Program Structure: Expected to conform to the specified grammar, encompassing a var section for variable declarations followed by a body containing executable statements.
• IR Execution: The execution process interprets the IR to simulate the runtime behavior of the input program, with support for basic arithmetic operations and control flow constructs.

Usage

To utilize this compiler, users are expected to have a basic C++ development environment. Compilation and execution instructions are as follows:

1. Compile the compiler source code using a C++ compiler (e.g., g++).
2. Execute the compiled binary, passing the path to the input program file as an argument.

Sample Input 1:

{
	input i;
  	i = 42 ;
  	j = i + 1; 
	output i;
	output j;
}
1 2 3

Expected Output 1:

42 43

Sample Input 2:

a  ;
{
input a;

WHILE  a > 0 {
	output a;
	a = a-1;
}
}
10 2 3 4

Expected Output 2:

10 9 8 7 6 5 4 3 2 1 

Sample Input 3:

j, i, minusfour, k ;

{
i = 4;
j = 3;

minusfour = 0-4;


WHILE i > 0 {
	j = 3;		
	WHILE j > 0 {
		k = i*j;
		output k;
		j = j-1;
	}
	i = i-1;
}

WHILE i > minusfour {
	output i;
	i = i - 1;
}

i = i+1;
j = j+1;
output i;
output j;

}
9 8 3 7

Sample Output 3

12 8 4 9 6 3 6 4 2 3 2 1 0 -1 -2 -3 -3 1