[Bug rtl-optimization/70134] combine misses jump optimization on powerpc64le

[segher at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70134

--- Comment #3 from Segher Boessenkool <segher at gcc dot gnu.org> ---
PowerPC has no simple way to set a CR field to "equal".  We could add
a pattern to do that (which will cost 2 insns, so works for 3->2
combinations, like we in fact get here; something like  li X,0 ; cmpwi X,0 ).

But, this is normally handled by cprop, and in fact it works like you
would hope if you just add -fgcse.  So is this a bug, or just something
-O1 does not do?