[Bug c/59615] "asm goto" output or at least clobbered operands

[glisse at gcc dot gnu.org]

http://gcc.gnu.org/bugzilla/show_bug.cgi?id=59615

--- Comment #8 from Marc Glisse <glisse at gcc dot gnu.org> ---
(In reply to Jakub Jelinek from comment #7)
> They are modelled in the .md files now, we just don't have general purpose
> builtins for this yet in GCC 4.9, it is only used for -fsanitize=undefined
> right now.

Ah, right, I thought you had only added an expander, nice that it is properly
modeled now (thanks), though I am yet to find C code where combine (or other)
ends up matching this pattern, which seems doable without a builtin. (well, we
are still losing the high half of the product if we use that pattern, but
that's less often needed)

Sorry for the hijack, back to comment 5 as the real motivation.