Reducing number of exception checks

Based on operations within an uncounted loop of source code, one or more calculations are generated for determining, at runtime, an expected number of iterations through which the uncounted loop can iterate before encountering an exception corresponding to at least one target exception check. A copy of the uncounted loop omitting each target exception check is generated. The uncounted loop, the copy of the uncounted loop, and the one or more calculations are arranged in compiled code so that at runtime program flow enters the copy of the uncounted loop. If a maximum number of iterations of the copy of the uncounted loop is reached, program flow proceeds from the copy of the uncounted loop to the uncounted loop. The maximum number of iterations is no more than the smallest member of a set consisting of the expected number of iterations for each target exception check.