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From: "H.J. Lu" <hjl.tools@gmail.com>
Date: Thu, 1 Jul 2021 16:01:45 -0700
Message-ID: <CAMe9rOrpT5YTi79fBndwMzYHQWbshfzUK3JSMY2EeKrLN-MxYQ@mail.gmail.com>
Subject: Re: [PATCH] Add optional _Float16 support
To: Joseph Myers <joseph@codesourcery.com>
Cc: IA32 System V Application Binary Interface <ia32-abi@googlegroups.com>,
 llvm-dev@lists.llvm.org, GNU C Library <libc-alpha@sourceware.org>,
 GCC Patches <gcc-patches@gcc.gnu.org>
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On Thu, Jul 1, 2021 at 3:40 PM Joseph Myers <joseph@codesourcery.com> wrote:
>
> On Thu, 1 Jul 2021, H.J. Lu wrote:
>
> > BTW, _Float16 software emulation may require more than just SSE
> > since we need to do _Float16 load and store with XMM registers.
> > There is no 16bit load/store for XMM registers without AVX512FP16.
>
> You should be able to make the move go via general-purpose registers (for
> example) if you can't do a direct 16-bit load/store for XMM registers.
>

There is no 16bit move between GPRs and XMM registers without
AVX512FP16.


-- 
H.J.