[llvm-dev] x86: How to Force 2-byte `jmp` instruction in lowering

Dean Michael Berris via llvm-dev llvm-dev at lists.llvm.org
Tue Jun 28 19:14:19 PDT 2016

On Wed, Jun 29, 2016 at 12:06 PM Rafael EspĂ­ndola <
rafael.espindola at gmail.com> wrote:

> On 22 June 2016 at 16:36, Dean Michael Berris via llvm-dev
> <llvm-dev at lists.llvm.org> wrote:
> > Peter suggested just writing out '.byte 0xeb, 0x09' and that allowed the
> > jump instruction to bypass the relaxation, so that fixes my immediate
> > problem. The question still stands though whether it should be possible
> to
> > do through the instruction builder interface.
> >
> I don't think so. When the relax-all flag is on MC will relax all
> instructions.
I see.

So the question becomes what's the advantage (if any) of Clang passing the
'relax-all' flag down to MC? Is there a good reason for this behaviour at

Thanks Rafael!
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