+
+/* Copies virtual operands from SRC to DST. */
+
+void
+copy_virtual_operands (tree dest, tree src)
+{
+ tree t;
+ ssa_op_iter iter, old_iter;
+ use_operand_p use_p, u2;
+ def_operand_p def_p, d2;
+
+ build_ssa_operands (dest);
+
+ /* Copy all the virtual fields. */
+ FOR_EACH_SSA_TREE_OPERAND (t, src, iter, SSA_OP_VUSE)
+ append_vuse (t);
+ FOR_EACH_SSA_TREE_OPERAND (t, src, iter, SSA_OP_VMAYDEF)
+ append_v_may_def (t);
+ FOR_EACH_SSA_TREE_OPERAND (t, src, iter, SSA_OP_VMUSTDEF)
+ append_v_must_def (t);
+
+ if (opbuild_num_elems (&build_vuses) == 0
+ && opbuild_num_elems (&build_v_may_defs) == 0
+ && opbuild_num_elems (&build_v_must_defs) == 0)
+ return;
+
+ /* Now commit the virtual operands to this stmt. */
+ finalize_ssa_v_must_defs (dest);
+ finalize_ssa_v_may_defs (dest);
+ finalize_ssa_vuses (dest);
+
+ /* Finally, set the field to the same values as then originals. */
+
+
+ t = op_iter_init_tree (&old_iter, src, SSA_OP_VUSE);
+ FOR_EACH_SSA_USE_OPERAND (use_p, dest, iter, SSA_OP_VUSE)
+ {
+ gcc_assert (!op_iter_done (&old_iter));
+ SET_USE (use_p, t);
+ t = op_iter_next_tree (&old_iter);
+ }
+ gcc_assert (op_iter_done (&old_iter));
+
+ op_iter_init_maydef (&old_iter, src, &u2, &d2);
+ FOR_EACH_SSA_MAYDEF_OPERAND (def_p, use_p, dest, iter)
+ {
+ gcc_assert (!op_iter_done (&old_iter));
+ SET_USE (use_p, USE_FROM_PTR (u2));
+ SET_DEF (def_p, DEF_FROM_PTR (d2));
+ op_iter_next_maymustdef (&u2, &d2, &old_iter);
+ }
+ gcc_assert (op_iter_done (&old_iter));
+
+ op_iter_init_mustdef (&old_iter, src, &u2, &d2);
+ FOR_EACH_SSA_MUSTDEF_OPERAND (def_p, use_p, dest, iter)
+ {
+ gcc_assert (!op_iter_done (&old_iter));
+ SET_USE (use_p, USE_FROM_PTR (u2));
+ SET_DEF (def_p, DEF_FROM_PTR (d2));
+ op_iter_next_maymustdef (&u2, &d2, &old_iter);
+ }
+ gcc_assert (op_iter_done (&old_iter));
+
+}
+
+
+/* Specifically for use in DOM's expression analysis. Given a store, we
+ create an artificial stmt which looks like a load from the store, this can
+ be used to eliminate redundant loads. OLD_OPS are the operands from the
+ store stmt, and NEW_STMT is the new load which represents a load of the
+ values stored. */
+
+void
+create_ssa_artficial_load_stmt (tree new_stmt, tree old_stmt)
+{
+ stmt_ann_t ann;
+ tree op;
+ ssa_op_iter iter;
+ use_operand_p use_p;
+ unsigned x;
+
+ ann = get_stmt_ann (new_stmt);
+
+ /* process the stmt looking for operands. */
+ start_ssa_stmt_operands ();
+ parse_ssa_operands (new_stmt);
+
+ for (x = 0; x < opbuild_num_elems (&build_vuses); x++)
+ {
+ tree t = opbuild_elem_virtual (&build_vuses, x);
+ if (TREE_CODE (t) != SSA_NAME)
+ {
+ var_ann_t ann = var_ann (t);
+ ann->in_vuse_list = 0;
+ }
+ }
+
+ for (x = 0; x < opbuild_num_elems (&build_v_may_defs); x++)
+ {
+ tree t = opbuild_elem_virtual (&build_v_may_defs, x);
+ if (TREE_CODE (t) != SSA_NAME)
+ {
+ var_ann_t ann = var_ann (t);
+ ann->in_v_may_def_list = 0;
+ }
+ }
+ /* Remove any virtual operands that were found. */
+ opbuild_clear (&build_v_may_defs);
+ opbuild_clear (&build_v_must_defs);
+ opbuild_clear (&build_vuses);
+
+ /* For each VDEF on the original statement, we want to create a
+ VUSE of the V_MAY_DEF result or V_MUST_DEF op on the new
+ statement. */
+ FOR_EACH_SSA_TREE_OPERAND (op, old_stmt, iter,
+ (SSA_OP_VMAYDEF | SSA_OP_VMUSTDEF))
+ append_vuse (op);
+
+ /* Now build the operands for this new stmt. */
+ finalize_ssa_stmt_operands (new_stmt);
+
+ /* All uses in this fake stmt must not be in the immediate use lists. */
+ FOR_EACH_SSA_USE_OPERAND (use_p, new_stmt, iter, SSA_OP_ALL_USES)
+ delink_imm_use (use_p);
+}
+
+static void
+swap_tree_operands (tree stmt, tree *exp0, tree *exp1)
+{
+ tree op0, op1;
+ op0 = *exp0;
+ op1 = *exp1;
+
+ /* If the operand cache is active, attempt to preserve the relative positions
+ of these two operands in their respective immediate use lists. */
+ if (ssa_operands_active () && op0 != op1)
+ {
+ use_optype_p use0, use1, ptr;
+ use0 = use1 = NULL;
+ /* Find the 2 operands in the cache, if they are there. */
+ for (ptr = USE_OPS (stmt); ptr; ptr = ptr->next)
+ if (USE_OP_PTR (ptr)->use == exp0)
+ {
+ use0 = ptr;
+ break;
+ }
+ for (ptr = USE_OPS (stmt); ptr; ptr = ptr->next)
+ if (USE_OP_PTR (ptr)->use == exp1)
+ {
+ use1 = ptr;
+ break;
+ }
+ /* If both uses don't have operand entries, there isn't much we can do
+ at this point. Presumably we dont need to worry about it. */
+ if (use0 && use1)
+ {
+ tree *tmp = USE_OP_PTR (use1)->use;
+ USE_OP_PTR (use1)->use = USE_OP_PTR (use0)->use;
+ USE_OP_PTR (use0)->use = tmp;
+ }
+ }
+
+ /* Now swap the data. */
+ *exp0 = op1;
+ *exp1 = op0;
+}
+