A method, implemented at a computer system that includes one or more processors and a memory, for using a recorded execution to determine whether a function-internal load modification affects one or more outputs of a traced function, the method comprising: accessing a recorded execution comprising trace data tracing a prior execution of at least a portion of executable code of an executable entity, the trace data enabling replay of the prior execution of the portion of the executable entity; identifying a function within the traced portion of executable code of the executable entity, the function comprising a sequence of executable instructions, the function consuming zero or more inputs and producing one or more outputs; based on the trace data, determining one or more traced output data values that were produced by a traced instance of the function during the prior execution; identifying, within the sequence of executable instructions of the function, at least one executable instruction that performs a load from memory; emulating execution of the function in reliance on the trace data, including: substituting a traced memory value loaded by the at least one executable instruction during the traced instance of the function with a different memory value; and producing one or more emulated output data values for the one or more outputs; comparing the one or more traced output data values and the one or more emulated output data values including determining if there is a difference between the one or more traced output data values and the one or more emulated output data values; analyzing the effects of substituting the traced memory value with a different memory value as part of a data race analysis including determining, based on the comparison, if substituting the traced memory value with the different memory value corresponds to a correction of a data race or a simulation of a data race; and outputting the results of the emulating of the function and the results of the analyzing comprising, based on there being a difference between the one or more traced output data values and the one or more emulated output data values, generating a notification at a user interface or to a software component. accessing a recorded execution comprising trace data tracing a prior execution of at least a portion of executable code of an executable entity, the trace data enabling replay of the prior execution of the portion of the executable entity; identifying a function within the traced portion of executable code of the executable entity, the function comprising a sequence of executable instructions, the function consuming zero or more inputs and producing one or more outputs; based on the trace data, determining one or more traced output data values that were produced by a traced instance of the function during the prior execution; identifying, within the sequence of executable instructions of the function, at least one executable instruction that performs a load from memory; emulating execution of the function in reliance on the trace data, including: substituting a traced memory value loaded by the at least one executable instruction during the traced instance of the function with a different memory value; and producing one or more emulated output data values for the one or more outputs; substituting a traced memory value loaded by the at least one executable instruction during the traced instance of the function with a different memory value; and producing one or more emulated output data values for the one or more outputs; comparing the one or more traced output data values and the one or more emulated output data values including determining if there is a difference between the one or more traced output data values and the one or more emulated output data values; analyzing the effects of substituting the traced memory value with a different memory value as part of a data race analysis including determining, based on the comparison, if substituting the traced memory value with the different memory value corresponds to a correction of a data race or a simulation of a data race; and outputting the results of the emulating of the function and the results of the analyzing comprising, based on there being a difference between the one or more traced output data values and the one or more emulated output data values, generating a notification at a user interface or to a software component.