Module Hooks.Constant_widening_thresholdsSource

Hook to collect widening thresholds.

The heuristic is simple: the hook tracks all comparisons between a numeric variable and a constant. It then adds the constant to the context of thresholds associated to the variable.

For better precision, a simple constant folding pass is performed on expressions. It replaces variables evaluated to singleton intervals with constants.

For better performances, only comparisons in loops are considered.