From: j.neuschaefer@gmx.net (Jonathan Neuschäfer)
To: kernelnewbies@lists.kernelnewbies.org
Subject: hi about C and asm
Date: Wed, 29 May 2013 17:33:59 +0200 [thread overview]
Message-ID: <20130529153359.GA3135@debian.debian> (raw)
In-Reply-To: <CA+5jrf=B1OpTbGNTU_aShBWg8_Qb25vyhn-vLZy2siYght5xPg@mail.gmail.com>
On Wed, May 29, 2013 at 09:02:22AM +0800, lx wrote:
> hi all:
> They are some asm codes in the kernel like:
>
> #define set_bit(nr,addr) ({\
> register int res __asm__("ax"); \
> __asm__ __volatile__("btsl %2,%3\n\tsetb %%al": \
> "=a" (res):"0" (0),"r" (nr),"m" (*(addr))); \
> res;})
>
>
> But, almost I can't understand this. So I want to understand asm in C,
> which book or website I should learn ?
Google "asm in c", first link is:
http://www.ibiblio.org/gferg/ldp/GCC-Inline-Assembly-HOWTO.html
HTH,
Jonathan Neusch?fer
prev parent reply other threads:[~2013-05-29 15:33 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2013-05-29 1:02 hi about C and asm lx
2013-05-29 1:27 ` Augusto Mecking Caringi
2013-05-29 15:33 ` Jonathan Neuschäfer [this message]
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