CSC448: AST Transformations: Eliminating High-Level Control Structures [50/133]

Constructs:

• if-then-else
• if-then
• while

Preservation of compound statements, lifetime of local variables

Peephole optimization

Further constructs:

• do-while
• repeat-until
• for
• switch:
  • fall through
  • default
  • efficiency
• continue / break:
  • enclosing blocks

  • "goto and Destructors in GNU C++

    In C++ programs, you can safely use the goto statement. When you use it to exit a block which contains aggregates requiring destructors, the destructors will run before the goto transfers control. (In ANSI C++, goto is restricted to targets within the current block.)

    The compiler still forbids using goto to enter a scope that requires constructors."