[Bug tree-optimization/67628] [tree-optimization] (a && b) && c shows better codegen than a && (b && c)

[ktkachov at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67628

--- Comment #2 from ktkachov at gcc dot gnu.org ---
(In reply to Andrew Pinski from comment #1)
> This is due to the fold-const.c optimization which should not be there any
> more. You need to do benchmarking on x86 also if you remove it. 
> 

could you elaborate what optimization is that?
Is it a matter of fold-const.c or match.pd canonicalizing the expression in
some way?