Richard Guenther wrote:
The middle-end knows about an explicit association barrier (only used from the Fortran FE sofar), a PAREN_EXPR. Would exposing that to C/C++ be of any help? For example it would, even with -ffast-math, avoid constant folding for (x + FLT_EPS) - FLT_EPS (which FLT_EPS such that proper rounding to the nearest integer value is performed).
Off the top of my head, I don't see anything both really useful and not-surprising in C/C++ here, but I may well miss something. There are some C++0x features, axiom and constexpr, which are related to this area. It's not clear yet to me how all this will interact, but I have good hope to see some connections there (like modeling some associativity rules with axioms). -- Sylvain Pion INRIA Sophia-Antipolis Geometrica Project-Team CGAL, http://cgal.org/
