Processor resources are partitioned based on memory usage. A compiler determines the extent to which a process is memory-bound and accordingly divides the process into a number of threads. When a first thread encounters a prolonged instruction, the compiler inserts a conditional branch to a second thread. When the second thread encounters a prolonged instruction, a conditional branch to a third thread is executed. This continues until the last thread conditionally branches back to the first thread. An indirect segmented register file is used so that the “return to” and “branch to” logical registers within each thread are the same (e.g., R1 and R2) for each thread. These logical registers are mapped to hardware registers that store actual addresses. The indirect mapping is altered to bypass completed threads. When the last thread completes it may signal an external process.