[lkml]   [2008]   [Dec]   [18]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
Messages in this thread
SubjectRe: PROC macro to annotate functions in assembly files
On Thu, 18 Dec 2008 11:44:27 +0000, "Russell King"
<> said:
> On Wed, Dec 17, 2008 at 12:12:14PM +0100, Alexander van Heukelum wrote:
> > Yeah, assembly files contain some interesting nesting. In this
> > particular case I think the solution is simple... Just use PROC
> > and ENDPROC around the complete functions, and leave the explicit
> > .global's for the additional entry points.
> I'm sorry, that doesn't work in all cases.
> On ARM with later toolchains, there's additional metadata associated with
> every symbol, and it's beginning to matter getting this right. That
> metadata includes whether it's a function, and more importantly whether
> the code pointed to by the symbol is Thumb or ARM.
> This leads to:
> ENTRY(__ashldi3)
> ENTRY(__aeabi_llsl)
> ...
> ENDPROC(__ashldi3)
> ENDPROC(__aeabi_llsl)
> and we want both of those symbols to have exactly the same attributes.
> Merely adding a .globl for the second name doesn't do that. It needs
> .globl, .size, and .type.
> So what you're actually talking about using your approach is enforcing
> the pairing of the existing ENTRY/ENDPROC and open coding everything
> else.

Note that enforcing the pairing will be enabled by ARCH code. Is the
construct you show here (two symbols covering identical code) the only
problem you forsee? I don't want to introduce too many macro's to
handle special cases, but this one should be solved.

> Forgive me if I think this is a backward step. It certainly seems to
> add some insane restrictions.

Some restrictions are introduced, indeed. And I agree that evading the
checking framework by doing things manually should be avoided.


> --
> Russell King
> Linux kernel 2.6 ARM Linux -
> maintainer of:
Alexander van Heukelum

-- - The way an email service should be

 \ /
  Last update: 2008-12-18 13:37    [W:0.054 / U:0.232 seconds]
©2003-2018 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site