Placement of explicit preemption points into compiled code

An apparatus for placement of explicit preemption points into compiled code, the apparatus comprising a computer processor, a computer memory operatively coupled to the computer processor, the computer memory having disposed within it computer program instructions that, when executed by the computer processor, cause the apparatus to carry out the steps of:

• creating, from executable code, a control flow graph that includes every control path in a function;
• determining, from the control flow graph, an estimated execution time for each control path;
• determining, for each control path, whether an estimated execution time of a control path exceeds a preemption latency parameter, wherein the preemption latency parameter is a maximum allowable time between preemption points, and wherein the estimated execution time is based on expected-case instruction timings for instructions along each control path;
• determining that the estimated execution time of a particular control path violates the preemption latency parameter;
• and
• placing an explicit preemption point into the executable code that satisfies the preemption latency parameter.

A computer program product for placement of explicit preemption points into compiled code, the computer program product comprising a non-transitory computer readable medium having computer program instructions embodied therewith that, when executed, cause a computer to carry out the steps of:

• creating, from executable code, a control flow graph that includes every control path in a function;
• determining, from the control flow graph, an estimated execution time for each control path;
• determining, for each control path, whether an estimated execution time of a control path exceeds a preemption latency parameter, wherein the preemption latency parameter is a maximum allowable time between preemption points, and wherein the estimated execution time is based on expected-case instruction timings for instructions along each control path;
• determining that the estimated execution time of a particular control path violates the preemption latency parameter;
• and
• placing an explicit preemption point into the executable code that satisfies the preemption latency parameter.