MapleCompiler

MapleCompiler is a compiler for a subset of the C language.

It is written in C++ and uses antlr4 for parsing.

Authors

• Tom Bourret
• Julien Charles-Nicolas
• Marc-Antoine Fernandes
• Justin Gally
• Vincent Guillon
• Loïc Sérazin

Compile

The project use cmake to compile.

To build an executable:

mkdir build
cd build
cmake ..
cmake --build . --target MapleCompiler -- -j 2

Testing

You can launch tests with:

ctest -V # -V to see cout

If you want to see some errors, programs are available in /tests directory.

Usage

./mapleCompiler [-a] [-o] [-c] [-l] [-t <x64|msp430|java>] <file.c>

• -a for static analysis
• -o for optimisation
• -c to generate ASM
• -l to create the executable
• -t to select target with x86 as default value

Current state

Language used

The subset include:

• Types for variables: char, int32_t, int64_t
• Initialization at declaration for variables
• One dimension arrays
• Function definition: functions without return type will use the type void
• Control structure: if, else, while
• Block structure with { and }
• Expressions: Every operators available in C including affectation
• Declaration of variables are always in the beginning of the function (before instructions)
• Global variables
• Global functions putchar and getchar for I/O
• A constant char like 'a'
• Only one source file with no pre-processing (will ignore every pre-processor directives)

Everything was implemented and is working, so we added some new things:

• for control structure
• String initialization as an array of char (or anything actually)
• Exponential notation like 5e2 (casted to an int64_t, so errors can appear!)
• Function declaration (to allow recursion between two functions)

Other changes

• During array initialization: We forbid a bigger list of values than the size of the array (e.g. a[1]={1,2} is not allowed)
• Arrays in arguments does not work as it implies pointers (it will not fail, but will be false!)
• We can assign an array to an int by passing the address of the tab to value of the int.
  • e.g. int a = tab; => int a = (int)(tab);
• Everything is cast without any checks!

Static analysis

Static analysis detect 3 potentials errors:

• If a variable is never used
• If a variables is never read
• If a variables is used before affectation

Back-end completion

• 5.1: Generate an empty frame
• 5.2: Understand activation registration and the ABI
• 5.3: Compile a program which executes a putchar()
• 5.4: Compile variable affectation
• 5.5: Compile expressions
• 5.6: Compile an if ... elseblock
• 5.7: Compile whileloops
• 5.8: Compile value return
• 5.9: Compile lvalue affectation with any value
• 5.10: Compile arrays
• 5.11: Compile function calls up to 6 arguments
• 5.12: Compile for loops
• 5.13: Complex programs testing (Collatz conjecture/Suite de Syracuse, Ackermann function, ...)
• 5.14: Correct handling of types (90%) -> Available on the branch type-size
• 5.15: Compile function callswith more than 6 arguments

License