1. A compiler for producing optimized computer programming code, said compiler embodied as a plurality of computer-executable instructions recorded on a non-transitory tangible computer-readable medium, said compiler comprising: an instrumentation function which places instrumentation hooks in a subset of respective paths in a first compiled version of a computer program, each instrumentation hook generating profile data during execution of said first compiled version of said computer program representing control flow in the respective path of the instrumentation hook to produce measured profile data, said subset of respective paths being fewer than all potential paths of said first compiled version of said computer program; an inferencing function, said inferencing function inferring profile data for control flow paths in said first compiled version of said computer program which are not in said subset to produce inferred profile data from said measured profile data; and a profile data adjustment function which uses at least one first heuristic to identify at least one error in profile data for at least one path in said first compiled version of said computer program inferred by said inferencing function and adjusts said error according to at least one second heuristic to produce adjusted inferred profile data from said measured profile data and said inferred profile data; wherein said compiler uses said measured profile data produced by said instrumentation hooks, said inferred profile data produced by said inferencing function, and said adjusted inferred profile data produced by said profile data adjustment function to generate an optimized version of said computer program.