Currently, I am using RL A3C algorithm for test data generation, where for a set of 30 functions written in C (mostly basic algorithms like Prime number checks, triangle validity, etc.) I try to generate a set of test data to have 100% coverage.
Now for this, I need to generate a matrix of these test data. To explain, lets say that we have 3 execution paths for the function and the function takes two parameters of integer. This means, that to have 100% code coverage, I need 3 function calls with different function parameters, hence a matrix of test data 3x2. But in reality, I can have a matrix of 12x5 and more, as the size of the matrix is varying.
What I have done now is, that with the help of this implementation: https://github.com/stefanbo92/A3C-Continuous of A3C I can generate a continuous value for one of the parameters of the function calls. I iterate through the functions, process the ASTs using a convolutional layer and generate a value for one cell in the matrix using a LSTM cell. Then I create the tests using this matrix and retrieve the coverage value. If the coverage is 90%+, I return a reward of 1, otherwise I return 0. I have also tried returning the coverage value as a reward, but with little to no changes in results.
Right now, I try to change the value separately for one cell in the matrix at a time and then generate a test and then get the coverage value. I think that this doesn't allow the agent to efficiently train on the data, as the action is only associated to the one value of the matrix, not the matrix in general (or the current row of the matrix). The current results only confirm this, as after around 1200 training episodes the coverage and reward stagnated and even dropped from the initial value.
As such, I would like my agent to not generate a continuous integer value for just one cell of the matrix, but ideally the entire matrix as one action.
I have no clue how to do this for varying matrix size, which I require, and I thought of using some sort of encoding/decoding, but have no clue as to have it could be achieved.
Any kind of advice is appreciated as to how to deal with this issue.
Thanks in advance.