MAVN to MIPS32 compiler

Here is a demonstration of a simple MAVN to MIPS32 assembly compiler.

The compiler can handle basic instructions that are used in MAVN language.

The compiler consists of a few phases:

1. Lexical Analysis
2. Syntax Analysis
3. Instructions, Variables and Labels gathering
4. Liveness Analysis
5. Resource Allocation: * Finding an interference graph * Simplification of register variables * Resource allocation to all register variables
6. Output to .S file

The output of this simple compiler is a .S file.

Lexical Analysis:

• Reads through the input file of the .mavn file
• Finds all tokens (words) in the mavn file
• Stores them in a container

Syntax Analysis:

• Reads through the container where lexicals are stored
• Goes token by token, finding if the variables are in order
• Makes sure the labels & variables are unique

Instructions, Variables and Labels gathering:

• While doing the Syntax Analysis, it reads token by token
• If the instruction consists of multiple variables, it stores them when it comes to that variable
• Instructions are lines of code, until the ;
• Labels are specifically read and stored

Liveness Analysis:

• Phase consists of finding the connections of all register variables
• Before liveness analysis, DEF and SRC variables are the same, DST exists
• After liveness analysis, OUT and IN are generated

Resource Allocation:

• This phase is for painting an intereference graph so it has the few variables used possible
• I implemented a simple solution which finds an interference graph, goes through the interference matrix and checks for neighbours
• If number of neighbours is less than the register number, it's okay; else, it spills (error is thrown)
• Resource allocation is the final step before the writing, so it maps all variables to syntax analysis's variables

Output to .S file:

• FileWritter is used to generate a stringstream object while is written into a .S file

Project provided by the subject OPPiSA (Osnovi Paralelnog Programiranja i Softverski Alati), RT-RK.