Testing our compiler

Run the main.py script using the following command: python main.py "input file". Our compiler will automatically produce the following:

• Parsed Concrete Syntax Tree pdf
• Converted Abstract Syntax Tree pdf
• LLVM Output (.ll extension)
• MIPS Output (.asm extension)

In order to run our compiler, run one of following commands:

python main.py <optimize: true/false>

This will run the compiler against all files present in the benchmark: CorrectCode and SemanticErrors, and produce the output in subfolders (asts/ and compiled_code/). This will most likely be the most helpful one for evaluation. It generates a

• benchmarks.log: file which includes all encountered errors (semantic/syntax/something else from our compiler) so you can easily see what went wrong when compiling each file. If successful, nothing is outputted to this log for the current c file.

• summary_benchmarks.log file: shows a summary of how many compilations were succesful, how many attempted compilations with syntax errors,... It also includes the percentage of success

As you will notice, in the SemanticErrors summary, there are a few SyntaxErrors instead of SemanticErrors. This is because some things might have been catched earlier, before needing to semantically check it. E.g: int a[0.5] will never work, as you may only give the size of a static array at compilation time instead of runtime, and you cannot enter a floating point as array access element.

python main.py <optimize: true/false>

Compiles the code present in the file and generates the output. Must be a file with a .c extension

Optimization

In order to facilitate the optimization feature, run the previous command but with a true after the filename.

The command would look like this:

python main.py "input file" true

Removed/adjusted in benchmark

In order to make the compiler work fully with our implemented features, we have removed/adjusted some files as these were optionals that we did not implement:

comparisons1.c
floatToIntConversion.c
intToFloatConversion.c
if.c: replaced && 1 with a nested if statement, as we don't support logical operators
ifElse.c: replaced && 1 with a nested if as we don't support logical operators

Features

Mandatory features

1. Binary operations: +, -, *, /, >, <, ==
   
2. Unary operations: +, -
3. Brackets (overwriting order of operations)
4. Supported data types: char, int, float and pointers (e.g. float**)
5. Special reserved words: const, if, else, while, for, break, continue, return and void
6. Variables
   6.0. Local and global variables
   6.1. Declaration
   6.2. Definition
   6.3. Assignments
   6.4. Identifiers appearing in expressions 7.Pointer operations: *, &
7. Comments: single-line, multi-line
8. Printf and Scanf functions
9. Scoping
10. Functions
    11.1. Passing parameters by value and by reference (pointers)
11. Optimizations: unreachable and dead code not implemented
12. Arrays
13. Import <stdio.h> (printf, scanf)

Optional features

1. Constant folding
2. Constant propagation: works with the reaching definition principle
3. Modulo operation: %
4. Comparison operations: <=, >=, !=
5. Identifier operations: ++, --
6. (Multiple variable declaration and/or initializations in one line, see benchmark prime.c for example)
7. Efficient register retrieval
   7.1. Depending on register and address descriptors
   7.2. Storing and loading only registers that are used in function

Added since intermediate presentation

Lots of bug fixes and improvements. Benchmark now running as it should.

Features that were not yet implemented:

1. Arrays and Global variables added
2. Scanf