On Fri, Jun 08, 2018 at 10:09:23AM -0700, Carl Love wrote:
> > > @@ -100,7 +152,6 @@ extract_uchar_15 (vector unsigned char a)
> > > /* { dg-final { scan-assembler "extsb " } } */
> > > /* { dg-final { scan-assembler "extsh " } } */
> > > /* { dg-final { scan-assembler "extsw " } } */
> > > -/* { dg-final { scan-assembler-not "m\[ft\]vsr" } } */
> > > /* { dg-final { scan-assembler-not "stxvd2x " } } */
> > > /* { dg-final { scan-assembler-not "stxv " } } */
> > > /* { dg-final { scan-assembler-not "lwa " } } */
> >
> > Why delete this? The changelog doesn't mention it either.
> >
> > Otherwise okay for trunk. Thanks!
>
> I went back and looked at that, it has been awhile since I did the
> patch and don't remember the details. The above occurs in file
> gcc/testsuite/gcc.target/powerpc/p9-extract-1.c. Reading the test
> file, there is a comment at the top that I probably didn't read before.
>
> /* Test that under ISA 3.0 (-mcpu=power9), the compiler optimizes conversion
> to
> double after a vec_extract to use the VEXTRACTU{B,H} or XXEXTRACTUW
>
> instructions (which leaves the result in a vector register), and not the
>
> VEXTU{B,H,W}{L,R}X instructions (which needs a direct move to do the
> floating
> point conversion). */
>
> So, the dg-final { scan-assembler-not "m\[ft\]vsr" is checking to make
> sure we are not using any direct moves. The new vec_extract tests with
> the "long long int" and "long long bool" are generating the move
> instruction. It looks like the existing GCC support for VEXTRACTU{B,H}
> or XXEXTRACTUW doesn't include support for extracting a double element.
Maybe split the test file in two, then? Or just do scan-assembler-times
for mfvsr and for mtvsr?
> There is a new Power 9 instruction vextractd for extracting double as
> well as the new Power 9 instructions vextractub, vextractuw,
> vextractuh. At first glance I didn't see an xxextractd or similar
> instruction. Will need to look further. So, that said, it looks like
> I really need to add the support to GCC to extract the double element.
> Based on a quick look at the code, that is not trivial. So, I have
> dropped the changes to file p9-extract-1.c from the patch. The updated
> patch is given below.
>
> Please let me know if this revised patch is OK for mainline. The
> changes to p9-extract-1.c will be addressed in a future patch. Thanks.
Looks fine to me. Okay for trunk. Thanks!
Segher
