Common lisp 如何在公共Lisp中内联函数

有人能告诉我如何在CommonLisp中内联函数吗？ 我有很多小函数，它们总是被调用，所以节省这些函数调用的成本是很好的

例如，如何在“调用者”函数中内联“独立”函数

(defun standalone ()
 (* 2 5))

(defun caller ()
 (standalone))

文件是

（但请记住，定义一个总是返回数字文本10的函数没有多大意义…

请参阅食谱：

如果编译器支持，内联声明将用函数体替换函数调用。它将节省函数调用的成本，但可能会增加代码大小。使用内联函数的最佳情况可能是那些小但常用的函数。下面的代码片段展示了如何鼓励和禁止内联代码

;; The globally defined function DISPATCH should be open-coded,
;; if the implementation supports inlining, unless a NOTINLINE 
;; declaration overrides this effect.
(declaim (inline dispatch))
(defun dispatch (x) (funcall (get (car x) 'dispatch) x))

;; Here is an example where inlining would be encouraged.
;; Because function DISPATCH was defined as INLINE, the code 
;; inlining will be encouraged by default.
(defun use-dispatch-inline-by-default () 
  (dispatch (read-command)))

;; Here is an example where inlining would be prohibited.
;; The NOTINLINE here only affects this function.
(defun use-dispatch-with-declare-notinline  ()
  (declare (notinline dispatch))
  (dispatch (read-command)))

;; Here is an example where inlining would be prohibited.
;; The NOTINLINE here affects all following code.
(declaim (notinline dispatch))
(defun use-dispatch-with-declaim-noinline () 
  (dispatch (read-command)))

;; Inlining would be encouraged becuase you specified it.
;; The INLINE here only affects this function.
(defun use-dispatch-with-inline () 
  (declare (inline dispatch))
  (dispatch (read-command)))

---

一些实现，如Allegro CL编译器

---

由

define compiler macro

（不同于

defmacro

）创建的宏也可以用于内联代码。

非常感谢，它很有效。实际上，“独立”函数没有任何意义，但我想知道函数调用的成本，我发现“独立”需要0.42秒，而“调用方”需要0.61秒（执行100000000次）。因此，添加的函数调用似乎消耗了“独立”函数总成本的50%。我不知道与其他语言相比，这种成本有多高，但我还是觉得它非常昂贵，值得担心。正如Ehvince在他的回答中指出的，内联与否是代码大小和执行时间之间的权衡。所有语言的调用机制都是类似的：在堆栈上推送返回地址、所有要更改的寄存器的值以及参数值，进行调用，将参数从堆栈中弹出；然后，在子例程调用结束时，恢复寄存器和返回地址，恢复堆栈并从那里恢复执行。有许多可能的复杂性（例如返回值的处理方式），但是，是的，函数调用是昂贵的。不可读的代码更是如此……感谢您提供了这个很棒的资源：）很有趣。不熟悉Allegro CL.“用户定义的函数从不内联编译。”这对于商业产品来说很奇怪。不相信他们的理由。你需要的是一个变量，而不是一个函数！

;; The globally defined function DISPATCH should be open-coded,
;; if the implementation supports inlining, unless a NOTINLINE 
;; declaration overrides this effect.
(declaim (inline dispatch))
(defun dispatch (x) (funcall (get (car x) 'dispatch) x))

;; Here is an example where inlining would be encouraged.
;; Because function DISPATCH was defined as INLINE, the code 
;; inlining will be encouraged by default.
(defun use-dispatch-inline-by-default () 
  (dispatch (read-command)))

;; Here is an example where inlining would be prohibited.
;; The NOTINLINE here only affects this function.
(defun use-dispatch-with-declare-notinline  ()
  (declare (notinline dispatch))
  (dispatch (read-command)))

;; Here is an example where inlining would be prohibited.
;; The NOTINLINE here affects all following code.
(declaim (notinline dispatch))
(defun use-dispatch-with-declaim-noinline () 
  (dispatch (read-command)))

;; Inlining would be encouraged becuase you specified it.
;; The INLINE here only affects this function.
(defun use-dispatch-with-inline () 
  (declare (inline dispatch))
  (dispatch (read-command)))