Declaration Variables In Minizinc Model

[rocbru]

In the 'claasp\components\modular_components.py' in the function: def cp_xor_differential_propagation_constraints(self, model): where you are creating the minizinc model for the differential constrain of the modular addition/substraction.

It is missing the declaration of the output variables, e.g. referring to a component of SPECK modadd_0_1 it is present the declarations of the inputs:

array[0..15] of var 0..1: pre_upper_modadd_0_1_0;
array[0..15] of var 0..1: pre_upper_modadd_0_1_1;

the constrains to merge these two inputs, but not the output i.e. modadd_0_1.

The declararions of the output it is happening outside this method, but it's confusing the developpers to have a compact understanding for the modular addition.

[SimoPez]

The choice of having the declarations of the component output variables all together in the model class was made to avoid having a duplicated declaration line in all the components for all the analysis types, also because not all the components have auxiliary variables. To us, this also makes it easier for the user to understand what the model class does at each step without going in the details of each component.

It may be true that, from a developer perspective, it can be confusing to read the declarations in the components modeling by themselves, as you say.

Thank you for pointing that out, we are discussing the issue and we will be sure to clarify that.

If you have any other comment or suggestion we'd be glad to hear that.

[rocbru]

Thank you very much for the answer. Could you indicate to me the file where the variables in the minizinc file are actually created please ?

[SimoPez]

Of course, you will find the output variables declarations in the input_xor_differential_constraints method in the mzn_xor_differential_model at line 536

[rocbru]

Thank you again

[juaninf]

I believe including the declaration at the output level could be beneficial—not only for developers, but also for anyone trying to understand which constraints and variables are involved in modeling a component. From what I’ve seen, having duplicated declarations is usually not an issue for most solvers, as they tend to handle such cases during their simplification or preprocessing phases.