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References: <b4d9aa23-d36c-4869-818c-c76a3db53392.bin.cheng@linux.alibaba.com>
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From: "Bin.Cheng" <amker.cheng@gmail.com>
Date: Mon, 26 Jul 2021 09:47:39 +0800
Message-ID: <CAHFci28sOSX4GYtmyNfd9zgxQPj_MmPa6ZkKfsS4TzNOZ3fz2w@mail.gmail.com>
Subject: Re: 0001-Don-t-skip-prologue-instructions-as-it-could-affect-.patch
To: Jeff Law <jeffreyalaw@gmail.com>
Cc: "bin.cheng" <bin.cheng@linux.alibaba.com>,
 GCC Patches <gcc-patches@gcc.gnu.org>
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On Sat, Jul 24, 2021 at 12:30 AM Jeff Law via Gcc-patches
<gcc-patches@gcc.gnu.org> wrote:
>
>
>
> On 7/14/2021 3:14 AM, bin.cheng via Gcc-patches wrote:
> > Hi,
> > I ran into a wrong code bug in code with deep template instantiation when working on sdx::simd.
> > The root cause as described in commit summary is we skip prologue insns in init_alias_analysis.
> > This simple patch fixes the issue, however, it's hard to reduce a case because of heavy use of
> > templates.
> > Bootstrap and test on x86_64, is it OK?
> It's a clear correctness improvement, but what's unclear to me is why
> we'd want to skip them in the epilogue either.
I can only guess, there is nothing to initialize epilogue for because
no code follows.

Thanks,
bin
>
> Jeff