From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugzilla@gcc.gnu.org>
Received: by sourceware.org (Postfix, from userid 48)
 id 7D1533982401; Fri, 26 Feb 2021 08:27:30 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 7D1533982401
From: "lh_mouse at 126 dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/99234] [10/11 regression] wrong result for 1.0/3.0 with
 -O2 -fno-omit-frame-pointer -frounding-math
Date: Fri, 26 Feb 2021 08:27:29 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: target
X-Bugzilla-Version: 10.2.1
X-Bugzilla-Keywords: wrong-code
X-Bugzilla-Severity: normal
X-Bugzilla-Who: lh_mouse at 126 dot com
X-Bugzilla-Status: ASSIGNED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: ebotcazou at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 10.2
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-99234-4-XlT6ank8WV@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-99234-4@http.gcc.gnu.org/bugzilla/>
References: <bug-99234-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: quoted-printable
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-BeenThere: gcc-bugs@gcc.gnu.org
X-Mailman-Version: 2.1.29
Precedence: list
List-Id: Gcc-bugs mailing list <gcc-bugs.gcc.gnu.org>
List-Unsubscribe: <https://gcc.gnu.org/mailman/options/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=unsubscribe>
List-Archive: <https://gcc.gnu.org/pipermail/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-request@gcc.gnu.org?subject=help>
List-Subscribe: <https://gcc.gnu.org/mailman/listinfo/gcc-bugs>,
 <mailto:gcc-bugs-request@gcc.gnu.org?subject=subscribe>
X-List-Received-Date: Fri, 26 Feb 2021 08:27:31 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D99234

--- Comment #15 from Liu Hao <lh_mouse at 126 dot com> ---
Thanks. The 'Final fix' looks good to me.

I applied it locally and built GCC. With a debugger, I verified that after =
the
try-catch statement, all non-volatile XMM registers (6-15) had been restored
properly.



```
// x86_64-w64-mingw32-g++ -O2 -fno-omit-frame-pointer test.cc

__attribute__((__noinline__)) void clobber_xmm6()
  {
    __asm__ volatile ("xorpd %%xmm6, %%xmm6" ::: "xmm6");
    throw 42;   // remove this to get expected result
  }

int main()
  {
    static const double xmm5  =3D  5.123456;
    static const double xmm6  =3D  6.123456;
    static const double xmm7  =3D  7.123456;
    static const double xmm8  =3D  8.123456;
    static const double xmm9  =3D  9.123456;
    static const double xmm10 =3D 10.123456;
    static const double xmm11 =3D 11.123456;
    static const double xmm12 =3D 12.123456;
    static const double xmm13 =3D 13.123456;
    static const double xmm14 =3D 14.123456;
    static const double xmm15 =3D 15.123456;
    __asm__ volatile ("movsd %0, %%xmm5 " :: "m"(xmm5 ));
    __asm__ volatile ("movsd %0, %%xmm6 " :: "m"(xmm6 ));
    __asm__ volatile ("movsd %0, %%xmm7 " :: "m"(xmm7 ));
    __asm__ volatile ("movsd %0, %%xmm8 " :: "m"(xmm8 ));
    __asm__ volatile ("movsd %0, %%xmm9 " :: "m"(xmm9 ));
    __asm__ volatile ("movsd %0, %%xmm10" :: "m"(xmm10));
    __asm__ volatile ("movsd %0, %%xmm11" :: "m"(xmm11));
    __asm__ volatile ("movsd %0, %%xmm12" :: "m"(xmm12));
    __asm__ volatile ("movsd %0, %%xmm13" :: "m"(xmm13));
    __asm__ volatile ("movsd %0, %%xmm14" :: "m"(xmm14));
    __asm__ volatile ("movsd %0, %%xmm15" :: "m"(xmm15));

    try {
      clobber_xmm6();
    }
    catch(...) { }

    double value;
    __asm__ volatile ("movsd %%xmm6, %0" : "=3Dx"(value));
    __builtin_printf("value =3D %g\n", value);      // expect `123.456`
  }


```=