> -----Original Message-----
> From: H.J. Lu <[email protected]>
> Sent: Sunday, September 28, 2025 9:11 AM
> To: Hongtao Liu <[email protected]>
> Cc: Liu, Hongtao <[email protected]>; [email protected]
> Subject: Re: [PATCH] Deprecate -mmove-max= and related tuning.
>
> On Sun, Sep 28, 2025 at 9:08 AM Hongtao Liu <[email protected]> wrote:
> >
> > On Sun, Sep 28, 2025 at 8:32 AM H.J. Lu <[email protected]> wrote:
> > >
> > > On Sun, Sep 28, 2025 at 8:18 AM Liu, Hongtao <[email protected]>
> wrote:
> > > >
> > > >
> > > >
> > > > > -----Original Message-----
> > > > > From: H.J. Lu <[email protected]>
> > > > > Sent: Sunday, September 28, 2025 6:33 AM
> > > > > To: Liu, Hongtao <[email protected]>
> > > > > Cc: [email protected]
> > > > > Subject: Re: [PATCH] Deprecate -mmove-max= and related tuning.
> > > > >
> > > > > On Fri, Sep 26, 2025 at 9:40 AM liuhongt <[email protected]>
> wrote:
> > > > > >
> > > > > > For memset, the size of used vector is decided by
> > > > > > MIN(MOVE_MAX_PIECES, STORE_MAX_PIECES).
> > > > > > Unless there's u-arch prefer big size vector for memcpy and
> > > > > > small size vector for memset, there's no need to have a
> > > > > > separate option or tune for it.
> > > > > > In general, x86 backend always prefer big size vector for
> > > > > > memset due to STLF issue.
> > > > > > So for maintaince convenience, the patch remove store_max
> > > > > > related tune and marked the mstore-max as deprecated.
> > > > > >
> > > > > > Bootstrapped and regtested on x86_64-pc-linux{-m32,}.
> > > > > > H.J Any comments?
> > > > >
> > > > > Does it change -mstore-max or -mmove-max? The subject says
> > > > > -mmove-max, but the commit message says -mstore-max.
> > > >
> > > > Typo, The patch only changes -mstore-max 1. It removes tune of
> > > > {AVX256,AVX512}_STORE_BY_PIECES.
> > > > 2. Deprecate mstore-max by aliasing it to -mmove-max and issues a
> warning.
> > >
> > > Does the patch include tests for -mmove-max aliasing and the warning
> message?
> > No, do we need it? It seems simple enough.
>
> Any change should have tests to verify that it is done correctly.
The change is also ready verified by adjusting testcase, those memset related
testcases will fail due to new warning message.
>
> --
> H.J.
