rs6000: MMA built-ins reject typedefs of MMA types

We do not allow conversions between the MMA types and other types.
However, we are being too strict in not matching MMA types with
typdefs of those types.  Use TYPE_CANONICAL to see through the
types to their canonical types before comparing them.

2020-08-08  Peter Bergner  <bergner@linux.ibm.com>

gcc/
	PR target/96530
	* config/rs6000/rs6000.c (rs6000_invalid_conversion): Use canonical
	types for type comparisons.  Refactor code to simplify it.

gcc/testsuite/
	PR target/96530
	* gcc.target/powerpc/pr96530.c: New test.

2 files changed, 51 insertions, 17 deletions

diff --git a/gcc/config/rs6000/rs6000.c b/gcc/config/rs6000/rs6000.c
index d26a18f..40ee0a6 100644
--- a/gcc/config/rs6000/rs6000.c
+++ b/gcc/config/rs6000/rs6000.c
@@ -26803,34 +26803,48 @@ rs6000_cannot_substitute_mem_equiv_p (rtx mem)
 static const char *
 rs6000_invalid_conversion (const_tree fromtype, const_tree totype)
 {
-  if (element_mode (fromtype) != element_mode (totype))
+  /* Make sure we're working with the canonical types.  */
+  if (TYPE_CANONICAL (fromtype) != NULL_TREE)
+    fromtype = TYPE_CANONICAL (fromtype);
+  if (TYPE_CANONICAL (totype) != NULL_TREE)
+    totype = TYPE_CANONICAL (totype);
+
+  machine_mode frommode = TYPE_MODE (fromtype);
+  machine_mode tomode = TYPE_MODE (totype);
+
+  if (frommode != tomode)
     {
       /* Do not allow conversions to/from PXImode and POImode types.  */
-      if (TYPE_MODE (fromtype) == PXImode)
+      if (frommode == PXImode)
 	return N_("invalid conversion from type %<__vector_quad%>");
-      if (TYPE_MODE (totype) == PXImode)
+      if (tomode == PXImode)
 	return N_("invalid conversion to type %<__vector_quad%>");
-      if (TYPE_MODE (fromtype) == POImode)
+      if (frommode == POImode)
 	return N_("invalid conversion from type %<__vector_pair%>");
-      if (TYPE_MODE (totype) == POImode)
+      if (tomode == POImode)
 	return N_("invalid conversion to type %<__vector_pair%>");
     }
   else if (POINTER_TYPE_P (fromtype) && POINTER_TYPE_P (totype))
     {
+      /* We really care about the modes of the base types.  */
+      frommode = TYPE_MODE (TREE_TYPE (fromtype));
+      tomode = TYPE_MODE (TREE_TYPE (totype));
+
       /* Do not allow conversions to/from PXImode and POImode pointer
 	 types, except to/from void pointers.  */
-      if (TYPE_MODE (TREE_TYPE (fromtype)) == PXImode
-	  && TYPE_MODE (TREE_TYPE (totype)) != VOIDmode)
-	return N_("invalid conversion from type %<* __vector_quad%>");
-      if (TYPE_MODE (TREE_TYPE (totype)) == PXImode
-	  && TYPE_MODE (TREE_TYPE (fromtype)) != VOIDmode)
-	return N_("invalid conversion to type %<* __vector_quad%>");
-      if (TYPE_MODE (TREE_TYPE (fromtype)) == POImode
-	  && TYPE_MODE (TREE_TYPE (totype)) != VOIDmode)
-	return N_("invalid conversion from type %<* __vector_pair%>");
-      if (TYPE_MODE (TREE_TYPE (totype)) == POImode
-	  && TYPE_MODE (TREE_TYPE (fromtype)) != VOIDmode)
-	return N_("invalid conversion to type %<* __vector_pair%>");
+      if (frommode != tomode
+	  && frommode != VOIDmode
+	  && tomode != VOIDmode)
+	{
+	  if (frommode == PXImode)
+	    return N_("invalid conversion from type %<* __vector_quad%>");
+	  if (tomode == PXImode)
+	    return N_("invalid conversion to type %<* __vector_quad%>");
+	  if (frommode == POImode)
+	    return N_("invalid conversion from type %<* __vector_pair%>");
+	  if (tomode == POImode)
+	    return N_("invalid conversion to type %<* __vector_pair%>");
+	}
     }
 
   /* Conversion allowed.  */
diff --git a/gcc/testsuite/gcc.target/powerpc/pr96530.c b/gcc/testsuite/gcc.target/powerpc/pr96530.c
new file mode 100644
index 0000000..29bb9e3
--- /dev/null
+++ b/gcc/testsuite/gcc.target/powerpc/pr96530.c
@@ -0,0 +1,20 @@
+/* PR target/96530 */
+/* { dg-do compile } */
+/* { dg-require-effective-target power10_ok } */
+/* { dg-options "-mdejagnu-cpu=power10 -O2" } */
+
+/* Verify we do not reject bar() below due to the typedef.  */
+
+typedef __vector_quad vquad_t;
+
+void
+foo (__vector_quad *dst)
+{
+  __builtin_mma_xxsetaccz (dst);
+}
+
+void
+bar (vquad_t *dst)
+{
+  __builtin_mma_xxsetaccz (dst);
+}