This is the mail archive of the
gcc-patches@gcc.gnu.org
mailing list for the GCC project.
Re: [PATCH, i386] Optionally use %xmm0 to return float and/or double values (take 3)
It seems that this may not be suitable for stage 3. Changing
calling conventions is always risky/tricky, even if it is for
local functions, and a best-case speedup of 1% when compiling
with specific options really isn't a compelling reason.
I'm especially worried about programs with assumptions that
static functions still follow normal calling conventions.
I know that's wrong, but it does happen. Would one still be
able to call these functions from GDB? Also, I assume that
when taking the address of a static function, this
optimization doesn't apply, right?
If you want to go this route of enabling %xmm0 as return register,
can you give a convincing argument this won't break anything?
How do other feel about this change?
-Geert