Remove nil check in exec_byte_code

Since we pass no arguments to a non-lexbind bytecode function, we can
specify its arity as 0 instead of nil and save a test and branch.

* src/bytecode.c (Fbyte_code, exec_byte_code):
* src/eval.c (fetch_and_exec_byte_code, funcall_lambda):
* src/lisp.h:
Change the args_template parameter type to ptrdiff_t, since it is now
always a small integer, in exec_byte_code and
fetch_and_exec_byte_code, all callers adjusted.

1 files changed, 6 insertions, 4 deletions

diff --git a/src/eval.c b/src/eval.c
index 8912e285252..910777e23d5 100644
--- a/src/eval.c
+++ b/src/eval.c
@@ -3222,15 +3222,16 @@ funcall_subr (struct Lisp_Subr *subr, ptrdiff_t numargs, Lisp_Object *args)
    bytecode string and constants vector, fetch them from the file first.  */
 
 static Lisp_Object
-fetch_and_exec_byte_code (Lisp_Object fun, Lisp_Object syms_left,
+fetch_and_exec_byte_code (Lisp_Object fun, ptrdiff_t args_template,
                           ptrdiff_t nargs, Lisp_Object *args)
 {
   if (CONSP (AREF (fun, COMPILED_BYTECODE)))
     Ffetch_bytecode (fun);
+
   return exec_byte_code (AREF (fun, COMPILED_BYTECODE),
                          AREF (fun, COMPILED_CONSTANTS),
                          AREF (fun, COMPILED_STACK_DEPTH),
-                         syms_left, nargs, args);
+                         args_template, nargs, args);
 }
 
 static Lisp_Object
@@ -3308,7 +3309,8 @@ funcall_lambda (Lisp_Object fun, ptrdiff_t nargs,
            argument-binding code below instead (as do all interpreted
            functions, even lexically bound ones).  */
         {
-          return fetch_and_exec_byte_code (fun, syms_left, nargs, arg_vector);
+          return fetch_and_exec_byte_code (fun, XFIXNUM (syms_left),
+                                           nargs, arg_vector);
         }
       lexenv = Qnil;
     }
@@ -3394,7 +3396,7 @@ funcall_lambda (Lisp_Object fun, ptrdiff_t nargs,
       val = XSUBR (fun)->function.a0 ();
     }
   else
-    val = fetch_and_exec_byte_code (fun, Qnil, 0, NULL);
+    val = fetch_and_exec_byte_code (fun, 0, 0, NULL);
 
   return unbind_to (count, val);
 }