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    SubjectRe: PROC macro to annotate functions in assembly files
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    On Thu, 18 Dec 2008 11:44:27 +0000, "Russell King"
    <rmk+lkml@arm.linux.org.uk> 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.

    Greetings,
    Alexander

    > --
    > Russell King
    > Linux kernel 2.6 ARM Linux - http://www.arm.linux.org.uk/
    > maintainer of:
    --
    Alexander van Heukelum
    heukelum@fastmail.fm

    --
    http://www.fastmail.fm - The way an email service should be



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