From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-476345-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 14556 invoked by alias); 7 Feb 2015 22:24:48 -0000
Mailing-List: contact gcc-bugs-help@gcc.gnu.org; run by ezmlm
Precedence: bulk
List-Id: <gcc-bugs.gcc.gnu.org>
List-Archive: <http://gcc.gnu.org/ml/gcc-bugs/>
List-Post: <mailto:gcc-bugs@gcc.gnu.org>
List-Help: <mailto:gcc-bugs-help@gcc.gnu.org>
Sender: gcc-bugs-owner@gcc.gnu.org
Received: (qmail 14441 invoked by uid 48); 7 Feb 2015 22:24:45 -0000
From: "ebotcazou at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug target/62631] gcc.dg/tree-ssa/ivopts-lt-2.c FAILs
Date: Sat, 07 Feb 2015 22:24:00 -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: 5.0
X-Bugzilla-Keywords:
X-Bugzilla-Severity: normal
X-Bugzilla-Who: ebotcazou at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: unassigned at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 5.0
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields:
Message-ID: <bug-62631-4-c7enL8SDo4@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-62631-4@http.gcc.gnu.org/bugzilla/>
References: <bug-62631-4@http.gcc.gnu.org/bugzilla/>
Content-Type: text/plain; charset="UTF-8"
Content-Transfer-Encoding: 7bit
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
MIME-Version: 1.0
X-SW-Source: 2015-02/txt/msg00678.txt.bz2

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=62631

--- Comment #26 from Eric Botcazou <ebotcazou at gcc dot gnu.org> ---
> The generated code on PA looks optimal to me:
> 
>         zdep %r25,29,30,%r28
>         b .L2
>         ldi 99,%r19
> .L6:
>         zdep %r25,29,30,%r28
> .L2:
>         addl %r26,%r28,%r28
>         ldo 1(%r25),%r25
>         comb,>>= %r19,%r25,.L6
>         stw %r0,0(%r28)
>         bv,n %r0(%r2)

For most other architectures the BIV (%r25) is eliminated to the GIV (%r28) so
you only have one additive operation in the loop.  This happens for 64-bit PA:

.L5:
        ldo 4(%r26),%r26
        cmpb,*>>,n %r28,%r26,.L5
        stw %r0,0(%r26)
        bve,n (%r2)

Why couldn't such a code be generated for 32-bit PA too?