[Bug tree-optimization/80738] dead first stmt in a=0;a=b;b=0 whatever the aliasing

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80738

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
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             Status|WAITING                     |NEW

--- Comment #5 from Richard Biener <rguenth at gcc dot gnu.org> ---
OK, so I guess std::vector<int>::_M_move_assign showed it in GCC 8 but then
with GCC 9 making 'this' restrict improved things here.  But _M_move_assing
has the stores/loads interleaved so the simple pattern-matching wouldn't work
since we'd have to look through non-aliasing VDEFs.