fix missing keep walker missing some cases

diff --git a/ir/be/beabihelper.c b/ir/be/beabihelper.c
index 2bba9b9..647a8bf 100644 (file)
--- a/ir/be/beabihelper.c
+++ b/ir/be/beabihelper.c
@@ -381,6 +381,46 @@ ir_node *be_epilog_create_return(beabi_helper_env_t *env, dbg_info *dbgi,
        return ret;
 }
 
+/**
+ * Tests wether a node has a real user and is not just kept by the End or
+ * Anchor node
+ */
+static bool has_real_user(const ir_node *node)
+{
+       const ir_edge_t *edge;
+       foreach_out_edge(node, edge) {
+               ir_node *user = get_edge_src_irn(edge);
+               if (!is_End(user) && !is_Anchor(user))
+                       return true;
+       }
+       return false;
+}
+
+static ir_node *add_to_keep(ir_node *last_keep,
+                            const arch_register_class_t *cls, ir_node *node)
+{
+       const ir_node *op;
+       if (last_keep != NULL) {
+               be_Keep_add_node(last_keep, cls, node);
+       } else {
+               ir_node *in[1] = { node };
+               ir_node *block = get_nodes_block(node);
+               ir_node *schedpoint;
+               last_keep = be_new_Keep(block, 1, in);
+
+               schedpoint = skip_Proj(node);
+               if (sched_is_scheduled(schedpoint)) {
+                       sched_add_after(schedpoint, last_keep);
+               }
+       }
+       op = skip_Proj_const(node);
+       if (arch_irn_get_flags(op) & arch_irn_flags_prolog)
+               arch_irn_add_flags(last_keep, arch_irn_flags_prolog);
+       if (arch_irn_get_flags(op) & arch_irn_flags_epilog)
+               arch_irn_add_flags(last_keep, arch_irn_flags_epilog);
+       return last_keep;
+}
+
 static void add_missing_keep_walker(ir_node *node, void *data)
 {
        int              n_outs, i;
@@ -389,8 +429,19 @@ static void add_missing_keep_walker(ir_node *node, void *data)
        ir_mode         *mode = get_irn_mode(node);
        ir_node         *last_keep;
        (void) data;
-       if (mode != mode_T)
+       if (mode != mode_T) {
+               if (!has_real_user(node)) {
+                       const arch_register_req_t   *req = arch_get_register_req_out(node);
+                       const arch_register_class_t *cls = req->cls;
+                       if (cls == NULL
+                                       || (cls->flags & arch_register_class_flag_manual_ra)) {
+                               return;
+                       }
+
+                       add_to_keep(NULL, cls, node);
+               }
                return;
+       }
 
        n_outs = arch_irn_get_n_outs(node);
        if (n_outs <= 0)
@@ -405,21 +456,20 @@ static void add_missing_keep_walker(ir_node *node, void *data)
                /* The node could be kept */
                if (is_End(succ) || is_Anchor(succ))
                        continue;
-
                if (mode == mode_M || mode == mode_X)
                        continue;
+               if (!has_real_user(succ))
+                       continue;
 
                pn = get_Proj_proj(succ);
                assert(pn < n_outs);
                rbitset_set(found_projs, pn);
        }
 
-
        /* are keeps missing? */
        last_keep = NULL;
        for (i = 0; i < n_outs; ++i) {
-               ir_node                     *block;
-               ir_node                     *in[1];
+               ir_node                     *value;
                const arch_register_req_t   *req;
                const arch_register_class_t *cls;
 
@@ -433,16 +483,8 @@ static void add_missing_keep_walker(ir_node *node, void *data)
                        continue;
                }
 
-               block = get_nodes_block(node);
-               in[0] = new_r_Proj(node, arch_register_class_mode(cls), i);
-               if (last_keep != NULL) {
-                       be_Keep_add_node(last_keep, cls, in[0]);
-               } else {
-                       last_keep = be_new_Keep(block, 1, in);
-                       if (sched_is_scheduled(node)) {
-                               sched_add_after(node, last_keep);
-                       }
-               }
+               value     = new_r_Proj(node, arch_register_class_mode(cls), i);
+               last_keep = add_to_keep(last_keep, cls, value);
        }
 }