[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:0.022 / U:65.264 seconds]
    ©2003-2016 Jasper Spaans. hosted at Digital OceanAdvertise on this site