On 04.20.2023 15:16, Xi Ruoyao wrote:
On Wed, 2023-04-19 at 23:53 -0700, Matthew R. Wilson wrote:
However, it looks like only the ..._round_to_odd versions of the
functions exist. But in the Power ISA 3.0, there are both the "normal"
version of the instruction (that use the rounding mode configured in the
floating-point control register, as all of the other floating point
instructions do) and the "round to odd" versions of the instructions.
Is there a particular reason this is the case, or is it indeed just an
oversight?
Because you can simply say "a + b":
https://godbolt.org/z/6a73xv11b
Well, that is indeed a good reason!
I have gcc-generated .s files built with -mcpu=power9 -mfloat128 and
they generated `bl __gcc_qadd` to perform the addition, which is why I
started going down the path of looking into the built-in functions.
But sure enough, I just tried it with my local GCC and it does directly
generate the xsaddqp instructions now. So I'm not sure what went wrong
with the compiler flags or whatever else with the earlier tests I have.
My mistake. Thank you!
-Matthew
