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From:   Alexei Starovoitov <alexei.starovoitov@gmail.com>
Date:   Tue, 1 Dec 2020 21:50:00 -0800
Message-ID: <CAADnVQJci_Fqq7d6GbUtivcmSgnPLbkwuH9MN30BhFomff=5rg@mail.gmail.com>
Subject: Re: [PATCH v2 bpf-next 01/13] bpf: x86: Factor out emission of ModR/M
 for *(reg + off)
To:     Brendan Jackman <jackmanb@google.com>
Cc:     bpf <bpf@vger.kernel.org>, Alexei Starovoitov <ast@kernel.org>,
        Yonghong Song <yhs@fb.com>,
        Daniel Borkmann <daniel@iogearbox.net>,
        KP Singh <kpsingh@chromium.org>,
        Florent Revest <revest@chromium.org>,
        LKML <linux-kernel@vger.kernel.org>, Jann Horn <jannh@google.com>
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On Tue, Dec 1, 2020 at 4:14 AM Brendan Jackman <jackmanb@google.com> wrote:
>
> On Sat, Nov 28, 2020 at 05:15:52PM -0800, Alexei Starovoitov wrote:
> > On Fri, Nov 27, 2020 at 05:57:26PM +0000, Brendan Jackman wrote:
> > > +/* Emit the ModR/M byte for addressing *(r1 + off) and r2 */
> > > +static void emit_modrm_dstoff(u8 **pprog, u32 r1, u32 r2, int off)
> >
> > same concern as in the another patch. If you could avoid intel's puzzling names
> > like above it will make reviewing the patch easier.
>
> In this case there is actually a call like
>
>   emit_modrm_dstoff(&prog, src_reg, dst_reg)

emit_insn_prefix() ?