From: bill4carson@gmail.com (bill4carson)
To: kernelnewbies@lists.kernelnewbies.org
Subject: Question about JUMP and LINK
Date: Tue, 20 Mar 2012 10:19:34 +0800 [thread overview]
Message-ID: <4F67E936.30000@gmail.com> (raw)
In-Reply-To: <CABi1daF6XkWM2zTQ93CNtv8DMMSOb=6U3rvmbo82DWJNg5SfdQ@mail.gmail.com>
On 2012?03?16? 23:23, Dave Hylands wrote:
> Hi Bill,
>
> On Thu, Mar 15, 2012 at 11:52 PM, bill4carson<bill4carson@gmail.com> wrote:
>> Hi, All
>>
>> The question is simple.
>>
>> func_a {
>>
>> call func_b
>> }
>>
>> func_b {
>>
>> call func_c
>> }
>>
>> func_c {
>>
>> return to func_a
>> }
>>
>>
>> The compiler I use let func_c to return func_a directly, IOW when func_b
>> calls func_c, it use JUMP, other JUMP and LINK, and it's definitely not
>> a question about inline or noinline.
>>
>> So can I ask why how to let the compiler use JUMP and LINK when func_b
>> calls func_c?
>
> This is called Tail Optimization. See
> http://c2.com/cgi/wiki?TailCallOptimization
>
> gcc (I'm using 4.4.4) with -O3 does this.
>
Thanks for the information.
>> If it's not the right place to post this, sorry for the noise.
>
> The kernel newbies list is probably not the right place (since this
> has nothing to do with the kernel). It also has nothing to do with
> binutils. It's a gcc optimization, so picking a gcc list would
> probably be more appropriate.
>
--
I am a slow learner
but I will keep trying to fight for my dreams!
--bill
prev parent reply other threads:[~2012-03-20 2:19 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2012-03-16 6:52 Question about JUMP and LINK bill4carson
2012-03-16 15:23 ` Dave Hylands
2012-03-20 2:19 ` bill4carson [this message]
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