[gcc r11-4773] tree-optimization/97732 - fix init of SLP induction vectorization

[gcc r11-4773] tree-optimization/97732 - fix init of SLP induction vectorization

[Richard Biener]

https://gcc.gnu.org/g:8ebedfcd86aa5e3fc902fb442ce12c9d440c23c8

commit r11-4773-g8ebedfcd86aa5e3fc902fb442ce12c9d440c23c8
Author: Richard Biener <rguenther@suse.de>
Date:   Fri Nov 6 09:35:27 2020 +0100

    tree-optimization/97732 - fix init of SLP induction vectorization
    
    This PR exposes two issues - one that the vector builder treats
    &x as eligible for VECTOR_CST elements and one that SLP induction
    vectorization forgets to convert init elements to the vector
    component type which makes a difference for pointer vs. integer.
    
    2020-11-06  Richard Biener  <rguenther@suse.de>
    
            PR tree-optimization/97732
            * tree-vect-loop.c (vectorizable_induction): Convert the
            init elements to the vector component type.
            * gimple-fold.c (gimple_build_vector): Use CONSTANT_CLASS_P
            rather than TREE_CONSTANT to determine if elements are
            eligible for VECTOR_CSTs.
    
            * gcc.dg/vect/bb-slp-pr97732.c: New testcase.

Diff:
---
 gcc/gimple-fold.c                          |  2 +-
 gcc/testsuite/gcc.dg/vect/bb-slp-pr97732.c | 11 +++++++++++
 gcc/tree-vect-loop.c                       |  4 ++++
 3 files changed, 16 insertions(+), 1 deletion(-)

diff --git a/gcc/gimple-fold.c b/gcc/gimple-fold.c
index c3fa4cb7cc1..ca38a31c3c2 100644
--- a/gcc/gimple-fold.c
+++ b/gcc/gimple-fold.c
@@ -7855,7 +7855,7 @@ gimple_build_vector (gimple_seq *seq, location_t loc,
   gcc_assert (builder->nelts_per_pattern () <= 2);
   unsigned int encoded_nelts = builder->encoded_nelts ();
   for (unsigned int i = 0; i < encoded_nelts; ++i)
-    if (!TREE_CONSTANT ((*builder)[i]))
+    if (!CONSTANT_CLASS_P ((*builder)[i]))
       {
 	tree type = builder->type ();
 	unsigned int nelts = TYPE_VECTOR_SUBPARTS (type).to_constant ();
diff --git a/gcc/testsuite/gcc.dg/vect/bb-slp-pr97732.c b/gcc/testsuite/gcc.dg/vect/bb-slp-pr97732.c
new file mode 100644
index 00000000000..5187090797d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/vect/bb-slp-pr97732.c
@@ -0,0 +1,11 @@
+/* { dg-do compile } */
+
+struct S { int a, b; } *e;
+int d;
+
+void
+foo (struct S *x)
+{
+  for (e = x; d; d++, e++)
+    e->a = e->b = (int) (__UINTPTR_TYPE__) e;
+}
diff --git a/gcc/tree-vect-loop.c b/gcc/tree-vect-loop.c
index ef2ea3d0fb0..0ba37540d5d 100644
--- a/gcc/tree-vect-loop.c
+++ b/gcc/tree-vect-loop.c
@@ -8001,6 +8001,10 @@ vectorizable_induction (loop_vec_info loop_vinfo,
 		{
 		  /* The scalar inits of the IVs if not vectorized.  */
 		  elt = inits[(ivn*const_nunits + eltn) % group_size];
+		  if (!useless_type_conversion_p (TREE_TYPE (vectype),
+						  TREE_TYPE (elt)))
+		    elt = gimple_build (&init_stmts, VIEW_CONVERT_EXPR,
+					TREE_TYPE (vectype), elt);
 		  init_elts.quick_push (elt);
 		}
 	      /* The number of steps to add to the initial values.  */