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没有尾调用优化的尾递归

[英]Tail recursion without tail call optimization

原文 2021-02-28 21:21:03 1 1 recursion/ optimization/ tail-recursion

Let say we had two versions of a recursive function, with one of them being tail-recursive.假设我们有两个版本的递归 function，其中一个是尾递归的。 Is there any benefit in using the function tail recursive if the language being used does not have tail-call optimization?如果使用的语言没有尾调用优化，那么使用 function 尾递归有什么好处？ From my understanding, without the optimization, each version of a function (tail and non-tail) would use the same number of stack frames (in most cases).据我了解，如果没有优化，function（尾部和非尾部）的每个版本都将使用相同数量的堆栈帧（在大多数情况下）。

I know that in some cases, like the Fibonacci function for example, using a tail call can be more efficient even without tail-call optimization since it avoids double calls.我知道在某些情况下，例如 Fibonacci function，即使没有尾调用优化，使用尾调用也会更有效，因为它避免了双重调用。 But what if neither version of the function makes double calls?但是，如果 function 的两个版本都没有进行双重调用怎么办？ Would the tail-recursive function still be more efficient?尾递归 function 还会更有效吗？

1 个解决方案

The answer to that question is hardware and language implementation dependent.该问题的答案取决于硬件和语言实现。 In most cases, however, I'd have to think that a simple GOTO is faster than CALL - RETURN instruction pair.然而，在大多数情况下，我不得不认为简单的GOTO比CALL - RETURN指令对更快。