ASDenysPetrov added a comment.
> ! In D103317#2793797 <https://reviews.llvm.org/D103317#2793797>, @vsavchenko > wrote: > I replied to you earlier that assignments are not producing constraints. The > analyzer has some sort of SSA (not really, but anyways), so every time we > reassign the variable it actually becomes a different symbol. So, from this > perspective `DeclRefExpr` `x` and symbol `x` are two different things: > > int x = foo(); // after this DeclRefExpr and VarDecl x are associated with > conjured symbol #1 (aka conj#1) > int c = x + 10; // c is associated with `$conj#1 + 10` > x = a + 1; // DeclRefExpr x is now associated with `$a + 1` > x = c + x; // and now it is `conj#1 + 11` > > There is no symbolic assignment in the static analyzer. Symbols are values, > values don't change. We can only obtain more information of what particular > symbolic value represents. > > I hope it makes it more clear. > > As for equality, we already track equivalence classes of symbols and they can > have more than 2 symbols in them. Actually, this whole data structure mostly > makes sense for cases when the class has more than 2 elements in it. Thanks for the clarifications. I'm trying to say that we need to keep our attention on assignments/initializations as well if we want to solve this problem efficiently. I didn't say that assignments produce constraints. Of course they do not :-). I want we produce more //bindings(associations)// on //assignments// to use them as mapping for further substitutions and traversing to get the right range. As for the equivalence classes. I think we should go away from special cases. I mean what about lower-then classes or greater-or-equal classes. I think you got what I mean. I'm trying to find a general approach which can cover almost all individual improvements around CSA codebase. I'm started working on this when saw your discussion. Just what you also consider the direction I'm moving. A lot of corner-examples, like you gave me, are welcome. Thank you for the feedbacks! Repository: rG LLVM Github Monorepo CHANGES SINCE LAST ACTION https://reviews.llvm.org/D103317/new/ https://reviews.llvm.org/D103317 _______________________________________________ cfe-commits mailing list cfe-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
