A system and method for instrumenting program instructions. A processing system includes a compiler and a profiler. The profiler is configured to instrument an application by inserting one or more instrumentation instructions in the application. During execution of the application, execution is monitored and a particular condition is detected. Responsive to the condition, a portion of the code which corresponds to the detected condition is identified. A request is conveyed for recompilation of code which corresponds to code. Prior to recompilation of the code, the profiler instruments the portion of code. Execution and monitoring of the execution continue, and instrumentation/recompilation may be repeated. Initially, relatively little of the application code may be instrumented. As execution and monitoring continues, more and more of the application code may be dynamically instrumented during execution.