CPSC 388 – Compiler Design and Construction.ppt

CPSC 388 – Compiler Design and Construction Evolution of Programming Languages Programming Language Basics Make Evolution of Programming Languages Types of Programming Languages Imperative Languages Declarative Languages Programming Language Basics Static/Dynamic Distinction Environments and States Static Scope and Block Structure Explicit Access Control Dynamic Scope Parameter Passing Aliasing Static / Dynamic Distinction Static Dynamic Environments and States Static vs. Dynamic binding of names to locations Globals can be static, others dynamic Static vs. Dynamic binding of locations to values Constants can be static, others dynamic (Strings in Java are imutable) Static Scope and Block Structure main() { int a = 1; int b = 1; { int b = 2; { int a = 3; cout a b; } { int b = 4; cout a b; } cout a b; } cout a b; } Explicit Access Control Classes introduce new scoping for data members. Subclasses act like sub-blocks public, private, and protected limit access to data members Dynamic Scope Use of name x refers to the declaration of x in the most recently called,not-yet-terminated, procedure with such a declaration. Dynamic Scoping vs. Static Scoping Static is most closely related declaration in space Dynamic is most closely related declaration in time Parameter Passing How do actual parameters associate to formal parameters? Call by Value Call by Reference Aliasing When two names refer to the same location in memory Effects optimization step of compilers Make Utility Defines which components go together to make a program. Defines how to put the pieces together. Keeps track of dependencies among components. Helps avoid doing unnecessary work and forgetting to do necessary work (in particular, it is usually used to control (re)compilation of code that depends on code in other files). Using Make Create a file named “makefile” or “Makefile” A makefile contains a set of rules containing a target (usually a file name) a lis