Creating

PIC compiler in

Tallinn 2016

Hannes Kinks

Agenda

• Tutorial on creating a simple PIC compiler
• Task - compiler for PIC counter program
• Consultation about homeworks

PIC compiler

Compilation

Flashing PIC with binary instructions

Compilation stages

Compilation of C code

• Preprocessing
• Compilation
• Assembly
• Linking

https://calleerlandsson.com/the-four-stages-of-compiling-a-c-program/

#include <stdio.h>             
#define MESSAGE "Hello world"  
                               
int main(void) {               
    printf(MESSAGE);           
    return 0;                  
}                              

Preprocessing

• Process the lines starting with #
• Join multi line statements (ending with \)
• To see the results of preprocessing

  • cc -E hello_world.c

https://calleerlandsson.com/the-four-stages-of-compiling-a-c-program/

Compilation

• Preprocessed code is translated into assembly instructions
• Specific to the target processor architecture
• Some compilators translate directly to machine code
• To see the result of this stage:

  • cc -S hello_world.c

https://calleerlandsson.com/the-four-stages-of-compiling-a-c-program/

Assembly

• Assembly instructions are translated to machine code (object code)
• We get binary instructions that can be executed by the processor
• To see the result of this stage:

  • cc -c hello_world.c

  • hexdump hello_world.o
    

https://calleerlandsson.com/the-four-stages-of-compiling-a-c-program/

Linking

• Inserts the missing object code from included libraries
• To produce an executable program, the existing pieces have to be rearranged and the missing ones filled in
• The result of this stage is the final executable program.
• To see the result of this stage:

  • cc hello_world.c

https://calleerlandsson.com/the-four-stages-of-compiling-a-c-program/

Getting started

• IDEA skeleton project for practice task

  • git clone https://bitbucket.org/hkinks/iag0450-antlr

    • data - input, output files
    • lib - libraries necessary to include in IDEA
    • doc - documentation, IDEA plugin

• Start idea, with
  • cad
  • idea&
• Go through the initial setup, until you reach the welcome screen
  • if root password is asked, just skip by closing it
• Add ANTLR4 plugin
  • Configure -> Plugins

• Add ANTLR4 plugin
  • Click on "Install plugin from disk ..."
  • Find and select
    • iag0450-antlr/doc/plugin.zip

• Import the cloned project
  • click on "Import Project"
  • select iag0450-antlr directory
  • Click "Next" until JDK installation
    is required
  • JDK location is:
    • /usr/lib64/jvm/java-1.7.0-openjdk-1.7.0
  • Finish the import

• Don't forget to generate ANTLR sources
  • Right click on *.g4 grammar file
  • Generate ANTLR recognizer
• Add the folder as source
  • Right click on gen folder
  • Mark Directory as
  • Generated Sources Root
• Try if everything works
  • Right click on Main
  • Run Main.main()
• Start developing the features

Blinking tutorial

https://bitbucket.org/hkinks/iag0450-antlr

Tutorial for blinking lights program compilation is included in the README.md file, down below.