middle-end/98793 - properly handle BLKmode vectors in vector_element_bits

The previous change made AVX512 mask vectors correct but disregarded
the possibility of generic (BLKmode) boolean vectors which are exposed
by the frontends already.

2021-01-22  Richard Biener  <rguenther@suse.de>

	PR middle-end/98793
	* tree.c (vector_element_bits): Key single-bit bool vector on
	integer mode rather than not vector mode.

	* gcc.dg/pr98793.c: New testcase.

2 files changed, 41 insertions, 3 deletions

diff --git a/gcc/testsuite/gcc.dg/pr98793.c b/gcc/testsuite/gcc.dg/pr98793.c
new file mode 100644
index 0000000..bb1ae9c
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr98793.c
@@ -0,0 +1,38 @@
+/* { dg-do run } */
+/* { dg-options "-O2 -Wno-psabi" } */
+
+typedef unsigned char u8;
+typedef unsigned char __attribute__((__vector_size__ (8))) v64u8;
+typedef unsigned char __attribute__((__vector_size__ (64))) v512u8;
+typedef unsigned long long u64;
+
+u64 gx;
+v512u8 gu;
+v512u8 gv;
+
+v64u8 __attribute__((__noipa__)) foo0 (u8 ax, v512u8 au, u64 ay)
+{
+  u8 lx = ax && (u8) ay;
+  v512u8 lc = 7 <= au;
+  v512u8 ld = (u8) (ay && gx) == gu;
+  v512u8 le = (v512u8) ld + (v512u8) gv;
+  v512u8 lf = le + lc;
+  return (((union
+            {
+            v512u8 a;
+            v64u8 b[8];
+            }) lf).b[3]) + lx;
+}
+
+int
+main (void)
+{
+  v64u8 x = foo0 (2, (v512u8) { 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
+                  0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 15
+                  },
+                  2);
+  for (unsigned i = 0; i < sizeof (x); i++)
+    if (x[i] != (i ? 0 : 0xff))
+      __builtin_abort ();
+  return 0;
+}
diff --git a/gcc/tree.c b/gcc/tree.c
index 061fe43..87862be 100644
--- a/gcc/tree.c
+++ b/gcc/tree.c
@@ -14028,11 +14028,11 @@ vector_element_bits (const_tree type)
   gcc_checking_assert (VECTOR_TYPE_P (type));
   if (VECTOR_BOOLEAN_TYPE_P (type))
     {
-      if (VECTOR_MODE_P (TYPE_MODE (type)))
+      if (SCALAR_INT_MODE_P (TYPE_MODE (type)))
+	return 1;
+      else
 	return vector_element_size (tree_to_poly_uint64 (TYPE_SIZE (type)),
 				    TYPE_VECTOR_SUBPARTS (type));
-      else
-	return 1;
     }
   return tree_to_uhwi (TYPE_SIZE (TREE_TYPE (type)));
 }