http://gcc.gnu.org/bugzilla/show_bug.cgi?id=54570
--- Comment #10 from Richard Biener <rguenth at gcc dot gnu.org> 2012-12-11 12:54:43 UTC --- An alternative suggestion was to allow arbitrary complex addresses (well, "arbitrary" == gimplified ADDR_EXPRs) in call arguments (either in general or just for specially marked builtins). That way they escape SSA based CSE. Yet another variant would be to have an optional 2nd operand for ADDR_EXPRs for the Frontend to fill in, specifying the "size" of the object at that address. Preserving that across propagation/substitution would be required of course (details on what the 'size' of &a[2] with int a[4]; would be is still to be determined). I'm leaning towards trying to have explicit information tracked from their origin rather than trying to re-discover them after optimizations obfuscated them.
