Cs topic 4

Cs topic 4

1. stages of compilation

   • lexical analysis
     • symbol table constuction
       • syntax analysis
         • semantic analysis
           • code genration
             • code optimisation
               • make it faster and more efficent
           • vebiles are checked if they have been proply declared and correct data types
           • operations are checked to ensure that they are legal for the types of variable being used
         • tokens are checked if to see if there valid aginst syntax of the programming language
       • makes a tabe with the addresses of varibles, labels and subroutines
     • unneeded things are removed (spaces and comments)
     • keywords, constants and identifiers are replaced by tokens

2. software tools

   • IDE - integrated development enviroment - assists with developing programs
   • trace - a log is created of user inputs, cariable changes and other events to help located logic errors
   • memory inspector
     • allows exact contents of memory locations within the computer can be displayed
   • statment completion - suggest auto fill for functions and statement and what veribles might be passed to it
   • complier and interpreter built in to make it faster to test the code

3. operating system

   • intfaces with the hardwear of the computer
   • manges inputs and outputs so software dosnt have to
   • spooling - makes a printer que unlits its ready to print
   • memory
     • memory is split into pages which improves sucirt as they are not able to access each others memory
   • processes
     • the oprating system divides the CPU time between alowing multitasking
   • security
     • paging, user authentication and permission
   • interface
     • provides GUI and/or command line interface to enable easy use of the system