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 99B57384C003; Fri,  5 Mar 2021 07:46:52 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org 99B57384C003
From: "rguenth at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug tree-optimization/98856] [11 Regression] botan AES-128/XTS is
 slower by ~17% since r11-6649-g285fa338b06b804e72997c4d876ecf08a9c083af
Date: Fri, 05 Mar 2021 07:46:51 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: tree-optimization
X-Bugzilla-Version: 11.0
X-Bugzilla-Keywords: missed-optimization, ra
X-Bugzilla-Severity: normal
X-Bugzilla-Who: rguenth at gcc dot gnu.org
X-Bugzilla-Status: ASSIGNED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: rguenth at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 11.0
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: attachments.created
Message-ID: <bug-98856-4-BxbSK5ZpJL@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-98856-4@http.gcc.gnu.org/bugzilla/>
References: <bug-98856-4@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, 05 Mar 2021 07:46:52 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D98856

--- Comment #23 from Richard Biener <rguenth at gcc dot gnu.org> ---
Created attachment 50300
  --> https://gcc.gnu.org/bugzilla/attachment.cgi?id=3D50300&action=3Dedit
preprocessed source of the important Botan TU

This is the full preprocessed source of the TU.  When compiled with -Ofast
-march=3Dznver2 look for poly_double_n_le in the assembly, in the prologue =
the
function jumps based on kernel size - size 16 is the important one:

        cmpq    $16, %rdx
        je      .L54
...
.L54:
        .cfi_restore_state
        vmovdqu (%rsi), %xmm4
        vmovdqa %xmm4, 16(%rsp)
        movq    24(%rsp), %rdx
        vmovdqa 16(%rsp), %xmm5
        shrq    $63, %rdx
        imulq   $135, %rdx, %rcx
        movq    16(%rsp), %rdx
        vmovq   %rcx, %xmm0
        vpsllq  $1, %xmm5, %xmm1
        shrq    $63, %rdx
        vpinsrq $1, %rdx, %xmm0, %xmm0
        vpxor   %xmm1, %xmm0, %xmm0
        vmovdqu %xmm0, (%rdi)
        leaq    -16(%rbp), %rsp
        popq    %r12
        popq    %r13
        popq    %rbp
        .cfi_remember_state
        .cfi_def_cfa 7, 8
        ret=