# Programming Assignment 2: LiveOak – 2 to SaM Compiler
## 1. Assignment Overview
### 1.1 Task
Create a handwritten recursive-descent parser and SaM code generator for levels 0, 1, and 2 of the LiveOak language. Use the provided SaMTokenizer class for lexical analysis. The compiler should take a file containing a LiveOak program as input and produce an output file containing a SaM program that is a correct translation of the input program. The assignment aims to help understand recursive-descent parsing and what it means to implement a compiler. Related lecture videos include LiveOak, stack machines and SaM, recursive-descent parsing, and code generation.
### 1.2 Score and Due Date
The score is 100 points. The due date is October 20th at 11:59 pm. You can use up to 2 late (extension) days.
### 1.3 Submission Method
All submissions are electronic. You can do the assignment on any machine. The submission testing is automated on Gradescope. You need to submit compiler.jar (a runnable.jar file of your project) and source.zip (a.zip file containing all your source files).
## 2. Preparation Materials
### 2.1 Required Materials
– The SaM library (v2.6.3) containing the lexer (obtained from Programming Assignment 1). Compile your code with this.jar file. If you use an IDE, you need to add this.jar file as an external library to your project.
– A collection of public test cases (still being expanded).
### 2.2 Optional Materials
– A starter template for your compiler, available here (https://utexas.instructure.com/courses/1404625/ files/79509966?wrap=1) (https://utexas.instructure.com/courses/1404625/files/79509966/ download?download_frd=1).
– The HTML documentation of the SaM API, available here (https://utexas.instructure.com/ courses/1404625/files/79016316?wrap=1) (https://utexas.instructure.com/courses/1404625/ files/79016316/download?download_frd=1).
– The design document containing the complete workings of the SaM interpreter, available here (https://utexas.instructure.com/courses/1404625/files/79016315?wrap=1) (https:// utexas.instructure.com/courses/1404625/files/79016315/download?download_frd=1).
## 3. Assignment Details
### 3.1 Grammar Related
– There will always be a main method in the input program. The program starts executing from the main method. The main method takes no parameters.
– There will always be a return statement at the end of a method in the input program.
– Comments in the input program are automatically handled by the SamTokenizer class.
– There is no overloading of methods.
– The definition of a method can occur either before or after calls to it. Each method needs a symbol table.
– A break statement must be lexically nested within one or more loops. When executed, it terminates the execution of the innermost loop in which it is nested. You are required to handle illegal break statements.
– If a program does not satisfy the grammar or the textual description of the language, the compiler should print a short error message and/or exit with a non-zero exit status.
### 3.2 Compiler Related
The compiler should be in the Java class assignment2.LiveOak2Compiler. It should take two command-line arguments. The first is an input file containing a LiveOak program. The second is an output file that will contain the generated SaM code. It is recommended to handle complexity by working up through the levels of the source language.
## 4. Evaluation
### 4.1 Evaluation Commands
– Compiling a LiveOak – 2 program: java -jar compiler.jar test1.lo output.sam
– Running a SaM program: java -cp SaM – 2.6.3.jar edu.utexas.cs.sam.ui.SamText output.sam
### 4.2 Evaluation Criteria
The compiler’s correctness is evaluated based on the program’s exit status. The public test cases are not exhaustive. It is highly recommended to create more test cases for testing. Before submitting the.jar file, make sure the exit status matches the expected output on all test cases.
## 5. Resources
The assignment counts for 30% of your course grade and is auto-graded using Gradescope. The names of the test cases indicate the level of the language they are testing. Grading is based only on the LiveOak – 2 test cases. Both public and private test cases will be used.