For optimizing executable code, during a first compilation of a source code, a set of signatures is inserted in a first executable code. A signature in the set of signatures includes a combination of executable instructions. During an execution of the first executable in a debugger an instruction to call a counter code is executed from a location of the signature to increment a counter corresponding to the signature. A value of the counter is provided to a compiler to correspond with the location of the signature in the first executable code. The source code is recompiled into a second executable code, optimizing a portion of the second executable code responsive to the value exceeding a threshold. The portion is related to the location of the signature in the first executable code.