Instructor: Gary T. Leavens
            HEC 329
            Leavens@ucf.edu
            407-823-4758

handouts: course policies and HW 0

         COP 5021 PROGRAM ANALYSIS

        WHAT IS PROGRAM ANALYSIS?

Def: *program analysis* is





        WHY PROGRAM ANALYSIS?

Automatic understanding of programs is
 - important for:
     + optimizing compilers
     + program development tools
     + formal verification:
        - safety critical systems
        - business critical systems
     + computer security
        - finding vulnerabilities
        - assurance for critical systems
     + research in programming languages
 - impossible, in general
    + safe approximations

    e.g., 
    read(x); (if x > 0 then y:= 1 else {y:= 2; f()}); z:=y
    -- can we say that z is 1 at the end?

Basic ideas:
 - compute abstractions
 - use in transformations

Goals:
  - little or no input from programmers


  - correctness

  - efficient (at compile time):
     - time
     - space




      MAIN IDEAS OR THEMES

- conservatism:
   "Err on the safe side!"

- efficiency from approximation:
   "Trade precision for efficiency!"


           PRECISION AND RECALL

def: the *precision* of an analysis is
     the fraction of



def: the *recall* of an analysis is
     the fraction of 



Example:
  Suppose a program has 10 vulnerabilities
  and a tool identifies 8 places
  but only 6 of those are actual ones

  The precision is

      recall is


        OBJECTIVES

- [Ideas] Correctly 
  understand and use terms
     for reading/writing papers
     when designing software tools

- [ImproveTools] Effectively 
  apply the concepts to design better
    software tools, 
    programming languages and tools.



               YOUR TASK

READ THE BOOK!
   See the readings in the syllabus

Goal: understand the material, so ask questions!