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Developers are often faced with a natural language change request (such as a bug report) and tasked with identifying all code elements that must be modified in order to fulfill the request (e.g., fix a bug or implement a new feature). In order to accomplish this task, developers frequently and routinely perform change impact analysis. This formal demonstration paper presents ImpactMiner, a tool that implements an integrated approach to software change impact analysis. The proposed approach estimates an impact set using an adaptive combination of static textual analysis, dynamic execution tracing, and mining software repositories techniques. ImpactMiner is available from our online appendix

1 while (t < threshold) { 2 t = 0; 3 for(i = 0; i < N; i++) 4 t += A[i] + B[i] * delta; 5 delta -= 0.1 * t; 6 } 1 for (i = 0; i < N; i++) 2 a += A[i]; b += B[i]; 3 while (t < threshold) { 4 t = a + b * delta; 5 delta -= 0.1 * t; 6 } Listing 1: An example code (on the left) with temporal inefficiencies that cannot be identified by existing fine-grained profilers. Because arrays A and B are immutable in the loop nest, computing on these loop invariants introduces many redundancies. One can hoist the redundant computation outside of the loop (on the right) for optimization. 1 int A[N] = {1, 1, 1, 15}; 2 for(i = 0; i < N; i++) 3 { 4 t += func(A[i]); 5 } 1 int A[N] = {1, 1, 1, 15}; 2 a = func(A[0]); 3 for(i = 0; i < N; i++) { 4 if (A[i] != A[i-1]) 5 a = func(A[i]); 6 t += a; }

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