Java 17 Compiler

This is the repo for the Course Project of CS335. This includes a complete implementation of Java 17 Compiler from scratch. The Compiler supports most of the features of Java 17. The compiler is written in C++ and uses flex and bison for lexical and syntax analysis. The compiler generates assembly code for the x86-64 architecture. The compiler is tested on Fedora 34 and GCC 12.2.1. Please refer to milestone4/doc/doc.pdf for detailed documentation.

List of features supported by the compiler:

• All primitive data types

• Multidimensional arrays

• All basic operators (arithmetic, increment, relational , bitwise ...)

• Control flow statements including if-else, for, while.

• Support for method calling.

• Support for recursion.

• Support for System.out.println() : Note this library is not supported, System.out.println() is provided for IO testing.

• Support for classes and objects.

• Syntax and Semantic checks have been implemented in accordance with https://docs.oracle.com/javase/specs/jls/se17/html/index.html

• Support for static methods and variables.

Installation and Execution

This is step by step execution section, check next section for end to end compilation. cd milestone4/src

make

cd ..

./a.out - -input ./path/input.java - -output ./path/output - This generates output_3ac.txt

cp ./path/output_3ac.txt ./outputs/proc.txt

python3 ./to86.py > asm.s - Generates assembly code in asm.s

gcc asm.s -o asm.out - Compiles assembly code to generate executable

./asm.out

Testing

I have provided an easy python script to automate the testing and bulk execution.

• Please change directory into ./milestone4/

• Execute python3 compiler.py

• The tests are named ./tests/test [1-10].java, corresponding outputs in- clude ./outputs/[1-10] symtable.csv, ./outputs/[1-10] 3ac.txt, ./outputs/asm[1- 10].s and ./outputs/asm[1-10].out, .out files indicate the final binaries.

• This script may be used by the tester for end-to-end evaluation as well. The number of test cases may be changed in line 10 of compiler.py and line 5 of run.py. Please ensure that tests are named correctly i.e. ./tests/test [1- 10].java.