mini-golang-compiler

Build and execution

• To ensure the code works well, you need make, g++, flex/lex and bison installed in your system.

• Clone this repository into your local system. The project has a single global lex file, while has separate yacc files for each of the phases to ensure code cleanliness and ease of maintenance.

• To build any of the phases, from a terminal, go into the directory and execute the MakeFile using the make command. It then builds the compiler into an executable in the name of gocompiler in that folder.

• To run the compiler with an input file testinput.go, from the same directory as the previous step run ./gocompiler testinput.go

Note: To help execute and test the compiler quickly, there are a set of prebuilt scripts in the scripts/ folder which will help build and execute predefined test cases using the compiler. Run sh <script-name>.sh

Task List

Lexical Analysis and Token Generation

• Conversion of strings to numbers.
• Handling Whitespace
• Handling Comments
• Update yylval, yylloc, other global variables (line and col nums) and return token code for each action.
• Record the line number and first and last column in yylloc for all tokens.
• Report lexical errors for improper strings, lengthy identifiers, and invalid characters.
• For each character that cannot be matched to any token pattern, report it and continue parsing with the next character.
• If an identifier is longer than the maximum (31 characters), report the error, truncate the identifier to the first 31 characters (discarding the rest), and continue.

Symbol Table generation

• Data Value for identifiers
• Line numbers for declaration and reference

CFG and Parsing (Syntax validation)

• Printing
• Variable declaration
• Const Declaration
• Assign Variables - int , float , string , bool , null
• Print String
• Simple arithmetic expressions
• Increment and decrement variables
• Boolean operations on variables
• If condition
• If else condition
• For loop
  • syntax validation
  • computation - Function
  • Function declaration
  • Function calls - Imports
  • Single import
  • Multiple imports - Identifiers
    • Compute Identifier values and insert in symbol table - [x] Print line number of syntax errors DONE - [x] Print col number of syntax errors - [ ] String computations - [x] Recognizing errors and suggesting fix - [x] Evaluate complex logical expressions

TAC

• Semmatic error analysis
• Print out semantic errors and continue parsing Currentlt stops parsing
• Quadraple format DONE
• Update Symbol table DONE

Optimisation

• Type 1 Optimisation ( Remove dead code/ unreachanble code ) DONE
• Type 2 Optimisation ( Copy Propagation ) DONE
• Type 3 Optimisation ( Constant Folding ) DONE
• Type 4 Optimisation ( Constant Propagation ) DONE

Look into

• Reduce conflicts
• Parser error recovery ? Even if its declaration related!

Deliverables

• CFG
• All the files related to all the tasks
• Symbol table with required Information
• ReadMe file for Syntax Error Handling Strategies
• Abstract syntax tree printed in an inorder way.
• ReadMe file for Semantic Error Handling
• Three address code (in Quadruple format) DONE
• Optimized Three address code. DONE
• ReadMe file for the Overall Tasks