Randomly branching using hardware watchpoints

Abstract

A system and method for efficiently performing program instrumentation. A processor processes instructions stored in a memory. The processor allocates a memory region for the purpose of creating 'random branches' in the computer code utilizing existing memory access instructions. When the processor processes a given instruction, the processor both accesses a first location in the memory region and may determine a condition is satisfied. In response, the processor generates an interrupt. The corresponding interrupt handler may transfer control flow from the computer program to instrumentation code. The condition may include a pointer storing an address pointing to locations within the memory region equals a given address after the point is updated. Alternatively, the condition may include an updated data value stored in a location pointed to by the given address equals a threshold value.