rs6000: Allow MMA built-in initialization regardless of compiler options

Built-in initialization occurs only once and fairly early, when the
command line options are in force.  If the -mcpu=<CPU> is pre-power10,
then we fail to initialize the MMA built-ins, so they are not
available to call in a #pragma target/attribute target function.
The fix is to basically always (on server type cpus) initialize the MMA
built-ins so we can use them in #pragma target/attribute target functions.

2020-07-09  Peter Bergner  <bergner@linux.ibm.com>

gcc/
	PR target/96125
	* config/rs6000/rs6000-call.c (rs6000_init_builtins): Define the MMA
	specific types __vector_quad and __vector_pair, and initialize the
	MMA built-ins if TARGET_EXTRA_BUILTINS is set.
	(mma_init_builtins): Don't test for mask set in rs6000_builtin_mask.
	Remove now unneeded mask variable.
	* config/rs6000/rs6000.c (rs6000_option_override_internal): Add the
	OPTION_MASK_MMA flag for power10 if not already set.

gcc/testsuite/
	PR target/96125
	* gcc.target/powerpc/pr96125.c: New test.

gcc/config/rs6000/rs6000-call.c

@@ -12572,7 +12572,7 @@ rs6000_init_builtins (void)
     ieee128_float_type_node = ibm128_float_type_node = long_double_type_node;
 
   /* Vector pair and vector quad support.  */
-  if (TARGET_MMA)
+  if (TARGET_EXTRA_BUILTINS)
     {
       tree oi_uns_type = make_unsigned_type (256);
       vector_pair_type_node = build_distinct_type_copy (oi_uns_type);
@@ -12648,13 +12648,14 @@ rs6000_init_builtins (void)
   pixel_V8HI_type_node = rs6000_vector_type ("__vector __pixel",
 					     pixel_type_node, 8);
 
-  /* Create Altivec and VSX builtins on machines with at least the
+  /* Create Altivec, VSX and MMA builtins on machines with at least the
      general purpose extensions (970 and newer) to allow the use of
      the target attribute.  */
   if (TARGET_EXTRA_BUILTINS)
-    altivec_init_builtins ();
+    {
-  if (TARGET_MMA)
+      altivec_init_builtins ();
-    mma_init_builtins ();
+      mma_init_builtins ();
+    }
   if (TARGET_HTM)
     htm_init_builtins ();
 
@@ -13388,20 +13389,12 @@ mma_init_builtins (void)
   for (unsigned i = 0; i < ARRAY_SIZE (bdesc_mma); i++, d++)
     {
       tree op[MAX_MMA_OPERANDS], type;
-      HOST_WIDE_INT mask = d->mask;
       unsigned icode = (unsigned) d->icode;
       unsigned attr = rs6000_builtin_info[d->code].attr;
       int attr_args = (attr & RS6000_BTC_OPND_MASK);
       bool gimple_func = (attr & RS6000_BTC_GIMPLE);
       unsigned nopnds = 0;
 
-      if ((mask & rs6000_builtin_mask) != mask)
-	{
-	  if (TARGET_DEBUG_BUILTIN)
-	    fprintf (stderr, "mma_builtin, skip binary %s\n", d->name);
-	  continue;
-	}
-
       if (d->name == 0)
 	{
 	  if (TARGET_DEBUG_BUILTIN)

gcc/config/rs6000/rs6000.c

@@ -4264,8 +4264,12 @@ rs6000_option_override_internal (bool global_init_p)
       rs6000_isa_flags &= ~OPTION_MASK_PCREL;
     }
 
+  /* Enable -mmma by default on power10 systems.  */
+  if (TARGET_POWER10 && (rs6000_isa_flags_explicit & OPTION_MASK_MMA) == 0)
+    rs6000_isa_flags |= OPTION_MASK_MMA;
+
   /* Turn off vector pair/mma options on non-power10 systems.  */
-  if (!TARGET_POWER10 && TARGET_MMA)
+  else if (!TARGET_POWER10 && TARGET_MMA)
     {
       if ((rs6000_isa_flags_explicit & OPTION_MASK_MMA) != 0)
 	error ("%qs requires %qs", "-mmma", "-mcpu=power10");

gcc/testsuite/gcc.target/powerpc/pr96125.c

@@ -0,0 +1,47 @@
+/* { dg-do compile } */
+/* { dg-require-effective-target powerpc_vsx_ok } */
+/* { dg-options "-mdejagnu-cpu=power7 -O2" } */
+
+void
+__attribute__((target("cpu=power10")))
+test0 (__vector_quad *dst)
+{
+  __vector_quad acc;
+  __builtin_mma_xxsetaccz (&acc);
+  *dst = acc;
+}
+
+void
+test1 (__vector_quad *dst)
+{
+  __vector_quad acc;
+  __builtin_mma_xxsetaccz (&acc); /* { dg-error "'__builtin_mma_xxsetaccz' requires the '-mmma' option" } */
+  *dst = acc;
+}
+
+#pragma GCC target("cpu=power10")
+void
+test2 (__vector_quad *dst)
+{
+  __vector_quad acc;
+  __builtin_mma_xxsetaccz (&acc);
+  *dst = acc;
+}
+
+void
+test3 (__vector_quad *dst)
+{
+  __vector_quad acc;
+  __builtin_mma_xxsetaccz (&acc);
+  *dst = acc;
+}
+
+#pragma GCC reset_options
+void
+test4 (__vector_quad *dst)
+{
+  __vector_quad acc;
+  __builtin_mma_xxmfacc (&acc); /* { dg-error "'__builtin_mma_xxmfacc' requires the '-mmma' option" } */
+  *dst = acc;
+}
+