MIPS Assembler and Example Programs

Overview

This mini-project includes a Python-based MIPS assembler (Assembler.py) and two example MIPS assembly programs:

• BinarySearch.asm: Implements a binary search algorithm in MIPS assembly.
• GCD.asm: Computes the Greatest Common Divisor (GCD) using the Euclidean algorithm.

The assembler reads a MIPS assembly file, converts it to machine code, and saves the output as MachineCode.txt.

Files

1. Assembler.py - A Python script that assembles MIPS code into machine code.
2. BinarySearch.asm - A MIPS assembly program for binary search.
3. GCD.asm - A MIPS assembly program for computing the GCD of two numbers.

How to Use

Running the Assembler

To assemble a MIPS program, run the Python script and enter the name of the .asm file (without the extension):

python Assembler.py  

The script will:

1. Prompt you to enter the name of the assembly file (e.g., BinarySearch).
2. Automatically append .asm to the filename.
3. Convert the MIPS assembly code into machine code.
4. Save the output as MachineCode.txt, overwriting any previous output.

Example

If you enter GCD when prompted, the script will process GCD.asm and create a MachineCode.txt file with the corresponding machine code.

Requirements

• Python 3.x
• A MIPS simulator (e.g., QtSPIM or Mars) to run the assembly programs

About Assembler.py

Assembler.py is a Python script that acts as a simple MIPS assembler. It processes MIPS assembly code and converts it into machine-readable binary format. The script follows these steps:

1. File Handling

   • Takes user input for the .asm filename.
   • Reads the assembly file line by line.

2. Instruction Parsing

   • Splits each line into operation (opcode) and operands.
   • Identifies instruction type (R-type, I-type, J-type).
   • Maps registers and immediate values to their respective binary representations.

3. Instruction Encoding

   • Converts parsed instructions into 32-bit binary format.
   • Expands pseudo-instructions into actual MIPS instructions (e.g., ble into slt and bne).

4. Handling Labels

   • Extracts labels and maps them to instruction addresses.
   • Replaces label references with correct jump/branch addresses.

5. Saving Output

   • Writes the converted machine code into MachineCode.txt.
   • Overwrites any previous output in MachineCode.txt.

Example Programs

Binary Search (BinarySearch.asm)

A MIPS assembly program that searches for a target element in a sorted array using binary search.

GCD Computation (GCD.asm)

A MIPS assembly program that computes the Greatest Common Divisor (GCD) using the Euclidean algorithm.

Future Improvements

• Extend assembler to support more MIPS instructions.
• Improve error handling and debugging features.