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 E4DA4396E46A; Mon, 19 Jul 2021 19:44:59 +0000 (GMT)
DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org E4DA4396E46A
From: "cvs-commit at gcc dot gnu.org" <gcc-bugzilla@gcc.gnu.org>
To: gcc-bugs@gcc.gnu.org
Subject: [Bug analyzer/101503] [12 Regression] ICE in involves_p, at
 analyzer/svalue.cc:557
Date: Mon, 19 Jul 2021 19:44:59 +0000
X-Bugzilla-Reason: CC
X-Bugzilla-Type: changed
X-Bugzilla-Watch-Reason: None
X-Bugzilla-Product: gcc
X-Bugzilla-Component: analyzer
X-Bugzilla-Version: 12.0
X-Bugzilla-Keywords: ice-on-valid-code
X-Bugzilla-Severity: normal
X-Bugzilla-Who: cvs-commit at gcc dot gnu.org
X-Bugzilla-Status: ASSIGNED
X-Bugzilla-Resolution: 
X-Bugzilla-Priority: P3
X-Bugzilla-Assigned-To: dmalcolm at gcc dot gnu.org
X-Bugzilla-Target-Milestone: 12.0
X-Bugzilla-Flags: 
X-Bugzilla-Changed-Fields: 
Message-ID: <bug-101503-4-Lbo7Ag7nXL@http.gcc.gnu.org/bugzilla/>
In-Reply-To: <bug-101503-4@http.gcc.gnu.org/bugzilla/>
References: <bug-101503-4@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: Mon, 19 Jul 2021 19:45:00 -0000

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=3D101503

--- Comment #2 from CVS Commits <cvs-commit at gcc dot gnu.org> ---
The master branch has been updated by David Malcolm <dmalcolm@gcc.gnu.org>:

https://gcc.gnu.org/g:a113b14398f2a4ad2742e6e9c87e25cac60f263e

commit r12-2399-ga113b14398f2a4ad2742e6e9c87e25cac60f263e
Author: David Malcolm <dmalcolm@redhat.com>
Date:   Mon Jul 19 15:44:02 2021 -0400

    analyzer: add svalue::can_have_associated_state_p [PR101503]

    PR analyzer/101503 reports an assertion failure due to an unexpected
    "UNKNOWN" value (due to using --param analyzer-max-svalue-depth=3D0).

    This patch fixes this by rejecting attempts to purge state involving
    unknown/poisoned svalues (in region_model::purge_state_involving),
    as these svalues should not have state associated with them - they
    are singletons w.r.t each type.

    To be more systematic about this, the patch also introduces a new
    svalue::can_have_associated_state_p which returns false for
    unknown/poisoned svalues, so that we can reject adding constraints
    or sm-state on them, or building various kinds of svalue in terms
    of them (e.g. unary ops, binary ops, etc).

    gcc/analyzer/ChangeLog:
            PR analyzer/101503
            * constraint-manager.cc (constraint_manager::add_constraint): U=
se
            can_have_associated_state_p rather than testing for unknown.
            (constraint_manager::get_or_add_equiv_class): Likewise.
            * program-state.cc (sm_state_map::set_state): Likewise.
            (sm_state_map::impl_set_state): Add assertion.
            * region-model-manager.cc
            (region_model_manager::maybe_fold_unaryop): Handle poisoned
            values.
            (region_model_manager::maybe_fold_binop): Move handling of unkn=
own
            values...
            (region_model_manager::get_or_create_binop): ...to here, and
            generalize to use can_have_associated_state_p.
            (region_model_manager::maybe_fold_sub_svalue): Use
            can_have_associated_state_p rather than testing for unknown.
            (region_model_manager::maybe_fold_repeated_svalue): Use unknown
            when the size or repeated value is "unknown"/"poisoned".
            * region-model.cc (region_model::purge_state_involving): Reject
            attempts to purge unknown/poisoned svalues, as these svalues
            should not have state associated with them.
            * svalue.cc (sub_svalue::sub_svalue): Assert that we're building
            on top of an svalue with can_have_associated_state_p.
            (repeated_svalue::repeated_svalue): Likewise.
            (bits_within_svalue::bits_within_svalue): Likewise.
            * svalue.h (svalue::can_have_associated_state_p): New.
            (unknown_svalue::can_have_associated_state_p): New.
            (poisoned_svalue::can_have_associated_state_p): New.
            (unaryop_svalue::unaryop_svalue): Assert that we're building on
            top of an svalue with can_have_associated_state_p.
            (binop_svalue::binop_svalue): Likewise.
            (widening_svalue::widening_svalue): Likewise.

    gcc/testsuite/ChangeLog:
            PR analyzer/101503
            * gcc.dg/analyzer/pr101503.c: New test.

    Signed-off-by: David Malcolm <dmalcolm@redhat.com>=