https://gcc.gnu.org/bugzilla/show_bug.cgi?id=87744
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
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CC| |jakub at gcc dot gnu.org
--- Comment #10 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
As discussed on IRC, probably the
if (!__builtin_mul_overflow(__l._M_lo, __x, &__lo))
optimization isn't a good idea, because most likely the compiler will in that
case
expand that to a full 64x64->128 multiplication plus testing that the upper 64
bits are or aren't zero, so computing everything this function needs and doing
it again if there is overflow, without possibility to query what it computed.
