[gcc r12-1996] Don't use vec_duplicate on vector in CTOR expansion

[gcc r12-1996] Don't use vec_duplicate on vector in CTOR expansion

[H.J. Lu]

https://gcc.gnu.org/g:52c3fdf3e4780f75297515d3c2a3dae9b36586ba

commit r12-1996-g52c3fdf3e4780f75297515d3c2a3dae9b36586ba
Author: H.J. Lu <hjl.tools@gmail.com>
Date:   Fri Jul 2 10:03:48 2021 -0700

    Don't use vec_duplicate on vector in CTOR expansion
    
    Since vec_duplicate only works on scalar, don't use it on vector in
    store constructor expansion.
    
    gcc/
    
            PR middle-end/101294
            * expr.c (store_constructor): Don't use vec_duplicate on vector.
    
    gcc/testsuite/
    
            PR middle-end/101294
            * gcc.dg/pr101294.c: New test.

Diff:
---
 gcc/expr.c                      |  3 ++-
 gcc/testsuite/gcc.dg/pr101294.c | 15 +++++++++++++++
 2 files changed, 17 insertions(+), 1 deletion(-)

diff --git a/gcc/expr.c b/gcc/expr.c
index 025033c9ecf..bd85bbfdd6f 100644
--- a/gcc/expr.c
+++ b/gcc/expr.c
@@ -7078,7 +7078,8 @@ store_constructor (tree exp, rtx target, int cleared, poly_int64 size,
 	    && eltmode == GET_MODE_INNER (mode)
 	    && ((icode = optab_handler (vec_duplicate_optab, mode))
 		!= CODE_FOR_nothing)
-	    && (elt = uniform_vector_p (exp)))
+	    && (elt = uniform_vector_p (exp))
+	    && !VECTOR_TYPE_P (TREE_TYPE (elt)))
 	  {
 	    class expand_operand ops[2];
 	    create_output_operand (&ops[0], target, mode);
diff --git a/gcc/testsuite/gcc.dg/pr101294.c b/gcc/testsuite/gcc.dg/pr101294.c
new file mode 100644
index 00000000000..ca59b35f4be
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr101294.c
@@ -0,0 +1,15 @@
+/* PR middle-end/101294 */
+/* { dg-do compile } */
+/* { dg-options "-O0" } */
+/* { dg-additional-options "-mavx" { target avx } } */
+
+typedef __attribute__((__vector_size__ (sizeof (unsigned long long)))) unsigned long long U;
+typedef __attribute__((__vector_size__ (4 * sizeof (unsigned long long)))) unsigned long long V;
+
+extern U x;
+
+void
+foo (void)
+{
+  x = __builtin_shufflevector ((U){}, (V){}, 3);
+}