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From:   Andrii Nakryiko <andrii.nakryiko@gmail.com>
Date:   Tue, 5 Jan 2021 21:13:09 -0800
Message-ID: <CAEf4BzZ_KLOiqR1jdcekui5uWTFjO9mt8+7UG8DKbUEdq0SHVQ@mail.gmail.com>
Subject: Re: [PATCH v3 3/4] bpftool: add support for ints larger than 128 bits
To:     Sean Young <sean@mess.org>
Cc:     Yonghong Song <yhs@fb.com>, Alexei Starovoitov <ast@kernel.org>,
        Daniel Borkmann <daniel@iogearbox.net>,
        Andrii Nakryiko <andrii@kernel.org>,
        Martin KaFai Lau <kafai@fb.com>,
        Song Liu <songliubraving@fb.com>,
        John Fastabend <john.fastabend@gmail.com>,
        KP Singh <kpsingh@kernel.org>,
        Nathan Chancellor <natechancellor@gmail.com>,
        Nick Desaulniers <ndesaulniers@google.com>,
        Quentin Monnet <quentin@isovalent.com>,
        =?UTF-8?B?VG9rZSBIw7hpbGFuZC1Kw7hyZ2Vuc2Vu?= <toke@redhat.com>,
        linux-doc@vger.kernel.org, Networking <netdev@vger.kernel.org>,
        bpf <bpf@vger.kernel.org>,
        open list <linux-kernel@vger.kernel.org>,
        clang-built-linux <clang-built-linux@googlegroups.com>
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On Tue, Jan 5, 2021 at 6:45 AM Sean Young <sean@mess.org> wrote:
>
> clang supports arbitrary length ints using the _ExtInt extension. This
> can be useful to hold very large values, e.g. 256 bit or 512 bit types.
>
> This requires the _ExtInt extension enabled in clang, which is under
> review.
>
> Link: https://clang.llvm.org/docs/LanguageExtensions.html#extended-integer-types
> Link: https://reviews.llvm.org/D93103
>
> Signed-off-by: Sean Young <sean@mess.org>
> ---

all the same comments as in patch #1

>  tools/bpf/bpftool/btf_dumper.c | 40 ++++++++++++++++++++++++++++++++++
>  1 file changed, 40 insertions(+)
>
> diff --git a/tools/bpf/bpftool/btf_dumper.c b/tools/bpf/bpftool/btf_dumper.c
> index 0e9310727281..8b5318ec5c26 100644
> --- a/tools/bpf/bpftool/btf_dumper.c
> +++ b/tools/bpf/bpftool/btf_dumper.c
> @@ -271,6 +271,41 @@ static void btf_int128_print(json_writer_t *jw, const void *data,
>         }
>  }

[...]