Change vec_perm checking and expansion level.

The can_vec_perm_p interface changed to use a C integer array.  This
allows easy re-use from the rtl level and the gimple level within
the vectorizer.  It allows both to determine if a given permutation
is (un-)supported without having to create tree/rtl garbage.

The expand_vec_perm interface changed to use rtl.  This allows easy
re-use from the rtl level, so that expand_vec_perm can be used in the
fallback implementation of other optabs.

        * target.def (vec_perm_const_ok): Change parameters to mode and
        array of indicies.
        * doc/tm.texi: Rebuild.
        * config/i386/i386.c (ix86_vectorize_vec_perm_const_ok): Change
        parameters to mode and array of indicies.
        * expr.c (expand_expr_real_2) [VEC_PERM_EXPR]: Expand operands here.
        * optabs.c (can_vec_perm_p): Rename from can_vec_perm_expr_p.
        Change parameters to mode and array of indicies.
        (expand_vec_perm_1): Rename from expand_vec_perm_expr_1.
        (expand_vec_perm): Rename from expand_vec_perm_expr.  Change
        parameters to mode and rtx inputs.  Try lowering to QImode
        vec_perm_const before trying fully variable permutation.
        * optabs.h: Update decls.
        * tree-vect-generic.c (lower_vec_perm): Extract array of indices from
        VECTOR_CST to pass to can_vec_perm_p.
        * tree-vect-slp.c (vect_get_mask_element): Change mask parameter type
        from int pointer to unsigned char pointer.
        (vect_transform_slp_perm_load): Update for change to can_vec_perm_p.
        * tree-vect-stmts.c (perm_mask_for_reverse): Likewise.

git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@180449 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 12 insertions, 2 deletions

diff --git a/gcc/tree-vect-generic.c b/gcc/tree-vect-generic.c
index 37ff807b1b5..42ce2e3d729 100644
--- a/gcc/tree-vect-generic.c
+++ b/gcc/tree-vect-generic.c
@@ -641,13 +641,23 @@ lower_vec_perm (gimple_stmt_iterator *gsi)
   location_t loc = gimple_location (gsi_stmt (*gsi));
   unsigned i;
 
-  if (can_vec_perm_expr_p (vect_type, mask))
+  if (TREE_CODE (mask) == VECTOR_CST)
+    {
+      unsigned char *sel_int = XALLOCAVEC (unsigned char, elements);
+      tree vals = TREE_VECTOR_CST_ELTS (mask);
+
+      for (i = 0; i < elements; ++i, vals = TREE_CHAIN (vals))
+	sel_int[i] = TREE_INT_CST_LOW (TREE_VALUE (vals));
+
+      if (can_vec_perm_p (TYPE_MODE (vect_type), false, sel_int))
+	return;
+    }
+  else if (can_vec_perm_p (TYPE_MODE (vect_type), true, NULL))
     return;
   
   warning_at (loc, OPT_Wvector_operation_performance,
               "vector shuffling operation will be expanded piecewise");
 
-
   v = VEC_alloc (constructor_elt, gc, elements);
   for (i = 0; i < elements; i++)
     {