https://gcc.gnu.org/bugzilla/show_bug.cgi?id=43892
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |jakub at gcc dot gnu.org
--- Comment #30 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Well, there is another way how to write it:
u32 z;
u32 y = __builtin_add_overflow (sum, x, &z);
return y + z;
and for the last 5 years GCC even pattern recognizes the #c0 way as the above
one.
Except that the powerpc backend doesn't define uaddv*4/usubv*4 expanders that
are needed for that (unlike aarch64, arm, x86, sparc, visium).
But if powerpc has instructions to efficiently handle double-word
additions/subtractions (as seen in this PR it has), it is really desirable to
implement those.
