From mboxrd@z Thu Jan  1 00:00:00 1970
Return-Path: <gcc-bugs-return-478013-listarch-gcc-bugs=gcc.gnu.org@gcc.gnu.org>
Received: (qmail 16950 invoked by alias); 20 Feb 2015 22:54:04 -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 16897 invoked by uid 48); 20 Feb 2015 22:54:01 -0000
From: "aldyh at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug debug/58315] [4.8/4.9/5 Regression] Excessive memory use with -g
Date: Fri, 20 Feb 2015 23:10:00 -0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: debug
X-Bugzilla-Version: 4.8.1
X-Bugzilla-Keywords: memory-hog
X-Bugzilla-Severity: normal
X-Bugzilla-Who: aldyh at gcc dot gnu.org
X-Bugzilla-Status: NEW
X-Bugzilla-Priority: P2
X-Bugzilla-Assigned-To: aldyh at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 4.8.5
X-Bugzilla-Flags:
X-Bugzilla-Changed-Fields: cc
Message-ID: <bug-58315-4-Esk6Hwa6n8@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-58315-4@http.gcc.gnu.org/bugzilla/>
References: <bug-58315-4@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/msg02345.txt.bz2

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=58315

Aldy Hernandez <aldyh at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
                 CC|                            |aoliva at gcc dot gnu.org,
                   |                            |rth at gcc dot gnu.org

--- Comment #14 from Aldy Hernandez <aldyh at gcc dot gnu.org> ---
I'm not very familiar with the var tracking code, but one thing I see odd here
is a ton of similar var_location notes attached to each instruction (well, not
each instruction, but a lot of the instructions are affected while generating
code for test01, test02, test03, test04, etc).

I see an instruction like this:

(insn:TI 52195 52199 83288 6386 (set (mem/c:DI (plus:DI (reg/f:DI 6 bp)
                (const_int -25880 [0xffffffffffff9ae8])) [125 %sfp+-25864 S8
A64])
        (reg:DI 0 ax)) 89 {*movdi_internal}
     (expr_list:REG_DEAD (reg:DI 0 ax)
        (nil)))
(jump_insn 83288 52195 83289 6386 (set (pc)
        (label_ref 34659)) 653 {jump}
     (nil)
 -> 34659)

Followed by over 1000 var_location notes:

(note 11489581 83289 11489582 (var_location this(0x7fffe7223360)  (plus:DI
(reg/f:DI 6 bp)
    (const_int -21808 [0xffffffffffffaad0]))) NOTE_INSN_VAR_LOCATION)
(note 11489582 11489581 11489583 (var_location this(0x7fffe8d7dc60)  (plus:DI
(reg/f:DI 6 bp)
    (const_int -25200 [0xffffffffffff9d90]))) NOTE_INSN_VAR_LOCATION)
(note 11489583 11489582 11489584 (var_location this(0x7fffe72236c0)  (plus:DI
(reg/f:DI 6 bp)
    (const_int -21856 [0xffffffffffffaaa0]))) NOTE_INSN_VAR_LOCATION)
(note 11489584 11489583 11489585 (var_location this(0x7fffe7223bd0)  (plus:DI
(reg/f:DI 6 bp)
    (const_int -6576 [0xffffffffffffe650]))) NOTE_INSN_VAR_LOCATION)
(note 11489585 11489584 11489586 (var_location this(0x7fffe7223cf0)  (plus:DI
(reg/f:DI 6 bp)
    (const_int -21872 [0xffffffffffffaa90]))) NOTE_INSN_VAR_LOCATION)
(note 11489586 11489585 11489587 (var_location this(0x7fffe941e090)  (plus:DI
(reg/f:DI 6 bp)
    (const_int -25136 [0xffffffffffff9dd0]))) NOTE_INSN_VAR_LOCATION)

etc
etc etc
.

Notice all of them are the "this" pointer, but I have hacked the RTL dumping
code to also print the address of the DECL to show that every "this" is
actually a different instance.

This looks suspect.  Anyone have a clue, otherwise I'm going to continue
banging my head against a wall here?