Kewen:

On Fri, 2023-06-30 at 15:20 -0700, Carl Love wrote:
> So, went to look at the assembly to verify my comment on the
> difference
> being related to the loads. I decided to actually count the
> instructions just to verify the number in the assembly files. 
> Before,
> I just looked at the assembly briefly but didn't dig in very deep.
> 
> If I compile the tests and dump the assembly with:
>   gcc -g -mcpu=power8 -o vsx-vector-6-func-2lop vsx-vector-6-func-
> 2lop.c
> 
>   objdump -S -d vsx-vector-6-func-2lop > vsx-vector-6-func-2lop.dump
>   
>   grep xxlor vsx-vector-6-func-2lop.dump | wc
>       4      28     192
> 
> So we see 4 xxlor instructions not 32 as expeced for BE or 22 as
> expected for LE as the test claims.  I get the same count of 4 on
> both
> makalu and on genoa. 

With a little help from Peter and Julian Wang.  Objdump decodes some of
the xxlor instructions as xxmr instsructions.  The xxmr is a new
mnemonic which will be out in the next ISA.  But objdump already
produces it.  So if you add the counts for grep xxlor and grep xxmr you
get a total of 34 which agress with the count of xxlor in the gcc -S
generated assembly.

                      Carl 

Reply via email to