}
/* Consecutive? */
- if (!tree_int_cst_compare (step, TYPE_SIZE_UNIT (scalar_type)))
+ if (!tree_int_cst_compare (step, TYPE_SIZE_UNIT (scalar_type))
+ || (dr_step < 0
+ && !compare_tree_int (TYPE_SIZE_UNIT (scalar_type), -dr_step)))
{
/* Mark that it is not interleaving. */
DR_GROUP_FIRST_DR (vinfo_for_stmt (stmt)) = NULL;
tree vptr;
gimple_stmt_iterator incr_gsi;
bool insert_after;
+ bool negative;
tree indx_before_incr, indx_after_incr;
gimple incr;
tree step;
*inv_p = true;
else
*inv_p = false;
+ negative = tree_int_cst_compare (step, size_zero_node) < 0;
/* Create an expression for the first address accessed by this load
in LOOP. */
LOOP is zero. In this case the step here is also zero. */
if (*inv_p)
step = size_zero_node;
+ else if (negative)
+ step = fold_build1 (NEGATE_EXPR, TREE_TYPE (step), step);
standard_iv_increment_position (loop, &incr_gsi, &insert_after);
if (!STMT_VINFO_DATA_REF (stmt_info))
return false;
+ if (tree_int_cst_compare (DR_STEP (dr), size_zero_node) < 0)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "negative step for store.");
+ return false;
+ }
+
if (STMT_VINFO_STRIDED_ACCESS (stmt_info))
{
strided_store = true;
return true;
}
+/* Given a vector type VECTYPE returns a builtin DECL to be used
+ for vector permutation and stores a mask into *MASK that implements
+ reversal of the vector elements. If that is impossible to do
+ returns NULL (and *MASK is unchanged). */
+
+static tree
+perm_mask_for_reverse (tree vectype, tree *mask)
+{
+ tree builtin_decl;
+ tree mask_element_type, mask_type;
+ tree mask_vec = NULL;
+ int i;
+ int nunits;
+ if (!targetm.vectorize.builtin_vec_perm)
+ return NULL;
+
+ builtin_decl = targetm.vectorize.builtin_vec_perm (vectype,
+ &mask_element_type);
+ if (!builtin_decl || !mask_element_type)
+ return NULL;
+
+ mask_type = get_vectype_for_scalar_type (mask_element_type);
+ nunits = TYPE_VECTOR_SUBPARTS (vectype);
+ if (TYPE_VECTOR_SUBPARTS (vectype) != TYPE_VECTOR_SUBPARTS (mask_type))
+ return NULL;
+
+ for (i = 0; i < nunits; i++)
+ mask_vec = tree_cons (NULL, build_int_cst (mask_element_type, i), mask_vec);
+ mask_vec = build_vector (mask_type, mask_vec);
+
+ if (!targetm.vectorize.builtin_vec_perm_ok (vectype, mask_vec))
+ return NULL;
+ if (mask)
+ *mask = mask_vec;
+ return builtin_decl;
+}
+
+/* Given a vector variable X, that was generated for the scalar LHS of
+ STMT, generate instructions to reverse the vector elements of X,
+ insert them a *GSI and return the permuted vector variable. */
+
+static tree
+reverse_vec_elements (tree x, gimple stmt, gimple_stmt_iterator *gsi)
+{
+ tree vectype = TREE_TYPE (x);
+ tree mask_vec, builtin_decl;
+ tree perm_dest, data_ref;
+ gimple perm_stmt;
+
+ builtin_decl = perm_mask_for_reverse (vectype, &mask_vec);
+
+ perm_dest = vect_create_destination_var (gimple_assign_lhs (stmt), vectype);
+
+ /* Generate the permute statement. */
+ perm_stmt = gimple_build_call (builtin_decl, 3, x, x, mask_vec);
+ data_ref = make_ssa_name (perm_dest, perm_stmt);
+ gimple_call_set_lhs (perm_stmt, data_ref);
+ vect_finish_stmt_generation (stmt, perm_stmt, gsi);
+
+ return data_ref;
+}
+
/* vectorizable_load.
Check if STMT reads a non scalar data-ref (array/pointer/structure) that
gimple first_stmt;
tree scalar_type;
bool inv_p;
+ bool negative;
bool compute_in_loop = false;
struct loop *at_loop;
int vec_num;
if (!STMT_VINFO_DATA_REF (stmt_info))
return false;
+ negative = tree_int_cst_compare (DR_STEP (dr), size_zero_node) < 0;
+ if (negative && ncopies > 1)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "multiple types with negative step.");
+ return false;
+ }
+
scalar_type = TREE_TYPE (DR_REF (dr));
mode = TYPE_MODE (vectype);
return false;
}
+ if (negative)
+ {
+ gcc_assert (!strided_load);
+ alignment_support_scheme = vect_supportable_dr_alignment (dr, false);
+ if (alignment_support_scheme != dr_aligned
+ && alignment_support_scheme != dr_unaligned_supported)
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "negative step but alignment required.");
+ return false;
+ }
+ if (!perm_mask_for_reverse (vectype, NULL))
+ {
+ if (vect_print_dump_info (REPORT_DETAILS))
+ fprintf (vect_dump, "negative step and reversing not supported.");
+ return false;
+ }
+ }
+
if (!vec_stmt) /* transformation not required. */
{
STMT_VINFO_TYPE (stmt_info) = load_vec_info_type;
else
at_loop = loop;
+ if (negative)
+ offset = size_int (-TYPE_VECTOR_SUBPARTS (vectype) + 1);
+
prev_stmt_info = NULL;
for (j = 0; j < ncopies; j++)
{
gcc_unreachable (); /* FORNOW. */
}
+ if (negative)
+ {
+ new_temp = reverse_vec_elements (new_temp, stmt, gsi);
+ new_stmt = SSA_NAME_DEF_STMT (new_temp);
+ }
+
/* Collect vector loads and later create their permutation in
vect_transform_strided_load (). */
if (strided_load || slp_perm)