Avoid Lisp_Misc allocation if C stack suffices

* src/fileio.c (union read_non_regular): New type.
(read_non_regular, Finsert_file_contents):
Use it to avoid	allocating a Lisp_Misc.
* src/keymap.c (union map_keymap): New type.
(map_keymap_char_table_item, map_keymap_internal):
Use it to avoid	allocating a Lisp_Misc.

1 files changed, 19 insertions, 7 deletions

diff --git a/src/keymap.c b/src/keymap.c
index c8cc933e782..982c014f01f 100644
--- a/src/keymap.c
+++ b/src/keymap.c
@@ -546,19 +546,29 @@ map_keymap_item (map_keymap_function_t fun, Lisp_Object args, Lisp_Object key, L
   (*fun) (key, val, args, data);
 }
 
+union map_keymap
+{
+  struct
+  {
+    map_keymap_function_t fun;
+    Lisp_Object args;
+    void *data;
+  } s;
+  GCALIGNED_UNION
+};
+verify (alignof (union map_keymap) % GCALIGNMENT == 0);
+
 static void
 map_keymap_char_table_item (Lisp_Object args, Lisp_Object key, Lisp_Object val)
 {
   if (!NILP (val))
     {
-      map_keymap_function_t fun
-        = (map_keymap_function_t) XSAVE_FUNCPOINTER (args, 0);
       /* If the key is a range, make a copy since map_char_table modifies
          it in place.  */
       if (CONSP (key))
         key = Fcons (XCAR (key), XCDR (key));
-      map_keymap_item (fun, XSAVE_OBJECT (args, 2), key,
-                       val, XSAVE_POINTER (args, 1));
+      union map_keymap *md = XINTPTR (args);
+      map_keymap_item (md->s.fun, md->s.args, key, val, md->s.data);
     }
 }
 
@@ -594,9 +604,11 @@ map_keymap_internal (Lisp_Object map,
             }
         }
       else if (CHAR_TABLE_P (binding))
-        map_char_table (map_keymap_char_table_item, Qnil, binding,
-                        make_save_funcptr_ptr_obj ((voidfuncptr) fun, data,
-                                                   args));
+        {
+          union map_keymap mapdata = {{fun, args, data}};
+          map_char_table (map_keymap_char_table_item, Qnil, binding,
+                          make_pointer_integer (&mapdata));
+        }
     }
 
   return tail;