From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-405999-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 23745 invoked by alias); 7 Nov 2012 22:12:02 -0000
Received: (qmail 23666 invoked by uid 48); 7 Nov 2012 22:11:47 -0000
From: "hjl.tools at gmail dot com" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug middle-end/55142] [4.8 Regression] internal compiler error: in plus_constant, at explow.c:88
Date: Wed, 07 Nov 2012 22:12:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: middle-end
X-Bugzilla-Keywords:
X-Bugzilla-Severity: normal
X-Bugzilla-Who: hjl.tools at gmail dot com
X-Bugzilla-Status: NEW
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: ebotcazou at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 4.8.0
X-Bugzilla-Changed-Fields:
Message-ID: <bug-55142-4-HuEQ0dkHsF@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-55142-4@http.gcc.gnu.org/bugzilla/>
References: <bug-55142-4@http.gcc.gnu.org/bugzilla/>
X-Bugzilla-URL: http://gcc.gnu.org/bugzilla/
Auto-Submitted: auto-generated
Content-Type: text/plain; charset="UTF-8"
MIME-Version: 1.0
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
X-SW-Source: 2012-11/txt/msg00661.txt.bz2


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=55142

--- Comment #21 from H.J. Lu <hjl.tools at gmail dot com> 2012-11-07 22:11:46 UTC ---
(In reply to comment #20)
> If you compile the testcase with the unmodified compiler but without -fPIC, you
> get in the assembly file:
> 
>         movl    %edx, _dl_rtld_map-1073742800(,%eax,4)
> 
> I presume that's wrong, correct?  Yet the RTL instruction is:

That is not wrong.

> (insn:TI 43 38 44 4 (set (mem/f:SI (zero_extend:DI (plus:SI (ashift:SI (reg:SI
> 0 ax [87])
>                         (const_int 2 [0x2]))
>                     (const:SI (plus:SI (symbol_ref:SI ("_dl_rtld_map") [flags
> 0x42]  <var_decl 0x7ffff6d2b7b8 _dl_rtld_map>)
>                             (const_int -1073742800 [0xffffffffbffffc30]))))) [3
> *_8+0 S4 A32])
>         (reg:SI 1 dx [orig:82 dyn ] [82])) pr55142.c:32 65 {*movsi_internal}
>      (expr_list:REG_DEAD (reg:SI 0 ax [87])
>         (nil)))
> 
> and there is a zero_extend.

(,%eax,4) generates a 0x67 address-size prefix, which zero-extends
32-bit address to 64-bit.