[Bug c/106017] New: [PowerPC] No array-to-pointer conversion for MMA accumulator

["nemanja.i.ibm at gmail dot com" <gcc-bugzilla@gcc.gnu.org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106017

            Bug ID: 106017
           Summary: [PowerPC] No array-to-pointer conversion for MMA
                    accumulator
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: c
          Assignee: unassigned at gcc dot gnu.org
          Reporter: nemanja.i.ibm at gmail dot com
  Target Milestone: ---

It appears that the typical array to pointer conversion for function arguments
does not work for MMA accumulator types. The user has to explicitly convert.

Code:
$ cat aa.c 
void takeacc(__vector_quad *);
void passacc() {
        __vector_quad arr[4];
#ifdef _EXPLICIT
        takeacc(&arr[0]);
#else
        takeacc(arr);
#endif
}

Compile (success):
$ gcc -mcpu=power10 -O3 aa.c -S -D_EXPLICIT && echo Success
Success

Compile (failure):
$ gcc -mcpu=power10 -O3 aa.c -S && echo Success
aa.c: In function 'passacc':
aa.c:7:9: error: invalid conversion to type '* __vector_quad'
    7 |         takeacc(arr);
      |         ^~~~~~~

Version:
$ gcc --version
gcc (GCC) 12.1.1 20220524 [releases/gcc-12 r12-8410-gf0a0aeec44]
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