tree-optimization/95356 - more vectorizable_shift massaging

The previous fix clashed with the rewrite to emit SLP invariants
during the SLP walk.  Thus the following adjusts the SLP tree
hacking vectorizable_shift does appropriately.

Still resisting the attempt of a rewrite of vectorizable_shift ...

2020-05-29  Richard Biener  <rguenther@suse.de>

	PR tree-optimization/95356
	* tree-vect-stmts.c (vectorizable_shift): Do in-place SLP
	node hacking during analysis.

diff --git a/gcc/tree-vect-stmts.c b/gcc/tree-vect-stmts.c
index a5f1b52..a6c7f33 100644 (file)
--- a/gcc/tree-vect-stmts.c
+++ b/gcc/tree-vect-stmts.c
@@ -5696,7 +5696,7 @@ vectorizable_shift (vec_info *vinfo,
 
       if (!op1_vectype)
        op1_vectype = get_vectype_for_scalar_type (vinfo, TREE_TYPE (op1),
-                                                  slp_node);
+                                                  slp_op1);
       incompatible_op1_vectype_p
        = (op1_vectype == NULL_TREE
           || maybe_ne (TYPE_VECTOR_SUBPARTS (op1_vectype),
@@ -5704,8 +5704,8 @@ vectorizable_shift (vec_info *vinfo,
           || TYPE_MODE (op1_vectype) != TYPE_MODE (vectype));
       if (incompatible_op1_vectype_p
          && (!slp_node
-             || SLP_TREE_DEF_TYPE
-                  (SLP_TREE_CHILDREN (slp_node)[1]) != vect_constant_def))
+             || SLP_TREE_DEF_TYPE (slp_op1) != vect_constant_def
+             || slp_op1->refcnt != 1))
        {
          if (dump_enabled_p ())
            dump_printf_loc (MSG_MISSED_OPTIMIZATION, vect_location,
@@ -5808,6 +5808,21 @@ vectorizable_shift (vec_info *vinfo,
                             "incompatible vector types for invariants\n");
          return false;
        }
+      /* Now adjust the constant shift amount in place.  */
+      if (slp_node
+         && incompatible_op1_vectype_p
+         && dt[1] == vect_constant_def)
+       {
+         for (unsigned i = 0;
+              i < SLP_TREE_SCALAR_OPS (slp_op1).length (); ++i)
+           {
+             SLP_TREE_SCALAR_OPS (slp_op1)[i]
+               = fold_convert (TREE_TYPE (vectype),
+                               SLP_TREE_SCALAR_OPS (slp_op1)[i]);
+             gcc_assert ((TREE_CODE (SLP_TREE_SCALAR_OPS (slp_op1)[i])
+                          == INTEGER_CST));
+           }
+       }
       STMT_VINFO_TYPE (stmt_info) = shift_vec_info_type;
       DUMP_VECT_SCOPE ("vectorizable_shift");
       vect_model_simple_cost (vinfo, stmt_info, ncopies, dt,
@@ -5882,20 +5897,8 @@ vectorizable_shift (vec_info *vinfo,
                    vec_oprnds1.quick_push (vec_oprnd1);
                }
              else if (dt[1] == vect_constant_def)
-               {
-                 /* Convert the scalar constant shift amounts in-place.  */
-                 slp_tree shift = SLP_TREE_CHILDREN (slp_node)[1];
-                 gcc_assert (SLP_TREE_DEF_TYPE (shift) == vect_constant_def);
-                 for (unsigned i = 0;
-                      i < SLP_TREE_SCALAR_OPS (shift).length (); ++i)
-                   {
-                     SLP_TREE_SCALAR_OPS (shift)[i]
-                         = fold_convert (TREE_TYPE (vectype),
-                                         SLP_TREE_SCALAR_OPS (shift)[i]);
-                     gcc_assert ((TREE_CODE (SLP_TREE_SCALAR_OPS (shift)[i])
-                                  == INTEGER_CST));
-                   }
-               }
+               /* The constant shift amount has been adjusted in place.  */
+               ;
              else
                gcc_assert (TYPE_MODE (op1_vectype) == TYPE_MODE (vectype));
            }