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From: "giuliano.belinassi at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/112980] 64-bit powerpc ELFv2 does not allow nops to be
 generated before function global entry point
Date: Mon, 01 Apr 2024 14:03:46 +0000
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https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D112980

--- Comment #9 from Giuliano Belinassi <giuliano.belinassi at gmail dot com=
> ---
Hello, Kewen.

(In reply to Kewen Lin from comment #8)
> Hi @Michael, @Martin, could you help to confirm/clarify what triggers you=
 to
> be interested in this feature, is it for some user space usage or not?

Yes, this is for userspace livepatching.

Assume the following example:
https://godbolt.org/z/b9M8nMbo1

As one can see, the sequence of 14 nops are generated after the global func=
tion
entry point. In such way we can't use the this space to place a trampoline =
to
the new function. We need this sequence of nops to be placed *before* the
global function entry point.

Thanks,
Giuliano.=