Using Action Points

TotalView provides a broad range of action points. (Action points are places in a program where you stop execution or evaluate an expression.)

Action points

You can set, delete, suppress, unsuppress, enable, and disable action points at the source and machine levels. TotalView lets you set the following action points:

• Breakpoints stop execution when a statement or instruction executes.
   
• Barrier breakpoints hold other threads until all threads in a group reach a "barrier" statement or instruction.
   
• Conditional breakpoints only perform an action if a code fragment (expression) is satisfied.
   
• Evaluation points execute code you create at a statement or instruction.
   
• Watchpoints monitor when changes occur to a variable's value.

Expressions and code fragments

TotalView lets you write and evaluate code fragments, including function calls used by the current process. While differences exist between platforms, you can write fragments in C, C++, Fortran, and assembler. On most platforms, TotalView compiles code fragments. This is a great way to test a fix without altering your source and recompiling it.