[Bug tree-optimization/30318] VRP does not create ANTI_RANGEs on overflow

[rguenth at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=30318

--- Comment #15 from Richard Guenther <rguenth at gcc dot gnu.org> 2012-05-07 13:50:17 UTC ---
Looking at your second patch it looks entirely reasonable, though not
globbing MULT_EXPR together with PLUS/MINUS might be better for readability
(thus, in the end I'd like extract_range_from_binary_expr_1 to be a big
switch-case on the operation code).  I didn't finish refactoring the code
when I last touched it - the idea was to have primitives for range
arithmetic.

I've looked at my own pending patch and it doesn't look as nicely structured
as yours.