Ola

Ola is a toy programming language with LLVM backend.

Dependencies

• LLVM 17.0.1 for compiler backend.
• spdlog for logging.
• CLI11 for command line parsing.

Features

• classes
  • access modifiers: public, private
  • constructors
  • single inheritance: :
  • polymorphism using vtables: virtual, pure, final
  • this and super keywords
• reference type: ref
• automatic type deduction: auto
• operators:
  • additive: +, -, +=, -=, ++, --
  • multiplicative: *, /, %, *=, /=, %=
  • relation: ==, !=, >, >=, <, <=
  • shift: >>, <<, >>=, <<=
  • bitwise: &, |, ^, ~, &=, |=, ^=
  • logic: &&, ||, !
• control statements: if else, switch, goto, ?:
• loop statements: for,foreach, while, do while, break, continue
• enums
• functions
  • overloading
  • attributes: inline, noinline, nomangling (equivalent to C++'s extern "C")
• arrays
• sizeof, length operators
• alias
• strings
• floats
• implicit casts
• scopes
• import statement
• standard library
• Custom backend
  • Custom IR and MIR
  • x86-64 code generation
  • todo:
    • references
    • classes
    • stack layout
    • IR optimization passes

Structure

Ola consists of three parts:

1. Ola library - standard library for Ola language implemented in C and built as static library to be used by the compiler. Currently it contains 5 files: olaio.h, olamath.h, olaassert.h, olastring.h, olamemory.h.
2. Ola compiler - consists of the following parts:
   • Lexer - turns source file into a sequence of tokens
   • Import Processor - receives tokens from previous phase and processes import statements.
   • Parser - recursive descent parser that receives processed tokens and constructs Abstract Syntax Tree (AST) of a translation unit.
   • Sema - does semantic analysis of a translation unit.
   • LLVM Visitor - traverses AST and emits LLVM IR.
   • LLVM Optimizer - applies optimizations to the generated LLVM IR produced by LLVM Visitor based on the optimization level used.
3. Ola tests
   • UnitTest framework for testing existing Ola features. Uses GoogleTest.

Usage

Command line options

• -h,--help: Print this help message and exit
• --astdump: Dump AST to output/log
• --testdebug: Print debug information during tests
• --test : used for running g-tests
• --Od : No optimizations
• --O0 : Same as --Od
• --O1 : Optimize
• --O2 : Optimize more
• --O3 : Optimize even more
• -i ... : Input files
• -o : Output file
• --directory : Directory of project files
• --simple : input code in the form of a string

Samples

Currently to see the samples you can check the test folder: OlaTests/Tests/.