[Bug target/78417] New: target_clones default for powerpc64

["tkoenig at gcc dot gnu.org" <gcc-bugzilla at gcc dot gnu dot org>]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=78417

            Bug ID: 78417
           Summary: target_clones default for powerpc64
           Product: gcc
           Version: 7.0
            Status: UNCONFIRMED
          Severity: normal
          Priority: P3
         Component: target
          Assignee: unassigned at gcc dot gnu.org
          Reporter: tkoenig at gcc dot gnu.org
  Target Milestone: ---

The following does not work as expected.

Either default is an invalid target for target_clones, or it is missing.
Bit of a Catch-22 there :-)

The reason why I'm interested is PR 78379; I think PowerPC could also
profit from processor-specific versions of matmul in the library.

[tkoenig@gcc1-power7 ~]$ cat target.c
static double foo_int(const double *restrict, const double *restrict, int)
__attribute__ ((target_clones("cpu=power7,cpu=power8,default")))
;

double foo(const double *restrict a, const double *restrict b, int n)
{
  return foo_int(a,b,n);
}

static double foo_int(const double *restrict a, const double *restrict b, int
n)
{
  double s;
  int i;
  s = 0.0;
  for (i=0; i<n; i++)
    s += a[i] * b[i];

  return s;
}
[tkoenig@gcc1-power7 ~]$ gcc -S target.c
target.c:19:1: error: __attribute__((__target__("default"))) is invalid
 }
 ^
target.c:10:15: error: attribute(target_clones("default")) is not valid for
current target
 static double foo_int(const double *restrict a, const double *restrict b, int
n)
               ^~~~~~~
[tkoenig@gcc1-power7 ~]$ cat t2.c
static double foo_int(const double *restrict, const double *restrict, int)
__attribute__ ((target_clones("cpu=power7,cpu=power8")))
;

double foo(const double *restrict a, const double *restrict b, int n)
{
  return foo_int(a,b,n);
}

static double foo_int(const double *restrict a, const double *restrict b, int
n)
{
  double s;
  int i;
  s = 0.0;
  for (i=0; i<n; i++)
    s += a[i] * b[i];

  return s;
}
[tkoenig@gcc1-power7 ~]$ gcc -S t2.c    
t2.c:10:15: error: default target was not set
 static double foo_int(const double *restrict a, const double *restrict b, int
n)
               ^~~~~~~
[tkoenig@gcc1-power7 ~]$ gcc -v
Using built-in specs.
COLLECT_GCC=gcc
COLLECT_LTO_WRAPPER=/home/tkoenig/libexec/gcc/powerpc64-unknown-linux-gnu/7.0.0/lto-wrapper
Target: powerpc64-unknown-linux-gnu
Configured with: ../trunk/configure --prefix=/home/tkoenig
--enable-languages=c,c++,fortran
Thread model: posix
gcc version 7.0.0 20161116 (experimental) (GCC)