[Bug analyzer/101503] New: [12 Regression] ICE in involves_p, at analyzer/svalue.cc:557

[Bug analyzer/101503] New: [12 Regression] ICE in involves_p, at analyzer/svalue.cc:557

[asolokha at gmx dot com]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101503

            Bug ID: 101503
           Summary: [12 Regression] ICE in involves_p, at
                    analyzer/svalue.cc:557
           Product: gcc
           Version: 12.0
            Status: UNCONFIRMED
          Keywords: ice-on-valid-code
          Severity: normal
          Priority: P3
         Component: analyzer
          Assignee: dmalcolm at gcc dot gnu.org
          Reporter: asolokha at gmx dot com
  Target Milestone: ---

gcc-12.0.0-alpha20210718 snapshot (g:6ae8aac19cdbdbd96d90f86e4d8505fe121bdf06)
ICEs when compiling the following testcase w/ -fanalyzer --param
analyzer-max-svalue-depth=0:

int val;

int
fn (void)
{
  val = fn ();

  return 0;
}

% gcc-12.0.0 -fanalyzer --param analyzer-max-svalue-depth=0 -c nllhdqtp.c
during IPA pass: analyzer
nllhdqtp.c: In function 'fn':
nllhdqtp.c:6:9: internal compiler error: in involves_p, at
analyzer/svalue.cc:557
    6 |   val = fn ();
      |         ^~~~~
0x76e65b ana::svalue::involves_p(ana::svalue const*) const
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/svalue.cc:557
0x124227e ana::binding_cluster::purge_state_involving(ana::svalue const*,
ana::region_model_manager*)
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/store.cc:1337
0x1244aaf ana::store::purge_state_involving(ana::svalue const*,
ana::region_model_manager*)
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/store.cc:2497
0x1215ee8 ana::region_model::purge_state_involving(ana::svalue const*,
ana::region_model_context*)
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/region-model.cc:1307
0x12160d0 ana::region_model::on_call_pre(gcall const*,
ana::region_model_context*, bool*)
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/region-model.cc:1074
0x1218e63 ana::region_model::on_stmt_pre(gimple const*, bool*, bool*,
ana::region_model_context*)
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/region-model.cc:1027
0x11e97bd ana::exploded_node::on_stmt(ana::exploded_graph&, ana::supernode
const*, gimple const*, ana::program_state*, ana::uncertainty_t*)
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/engine.cc:1223
0x11ebd52 ana::exploded_graph::process_node(ana::exploded_node*)
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/engine.cc:3098
0x11ec8ba ana::exploded_graph::process_worklist()
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/engine.cc:2684
0x11eed15 ana::impl_run_checkers(ana::logger*)
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/engine.cc:4972
0x11efbb0 ana::run_checkers()
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/engine.cc:5043
0x11e0c78 execute
       
/var/tmp/portage/sys-devel/gcc-12.0.0_alpha20210718/work/gcc-12-20210718/gcc/analyzer/analyzer-pass.cc:87

[Bug analyzer/101503] [12 Regression] ICE in involves_p, at analyzer/svalue.cc:557

[rguenth at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101503

Richard Biener <rguenth at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Target Milestone|---                         |12.0

[Bug analyzer/101503] [12 Regression] ICE in involves_p, at analyzer/svalue.cc:557

[dmalcolm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101503

David Malcolm <dmalcolm at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
   Last reconfirmed|                            |2021-07-19
             Status|UNCONFIRMED                 |ASSIGNED
     Ever confirmed|0                           |1

--- Comment #1 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
Thanks for filing this bug.

Confirmed; am working on a fix.

[Bug analyzer/101503] [12 Regression] ICE in involves_p, at analyzer/svalue.cc:557

[cvs-commit at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101503

--- 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=0).

    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): Use
            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 unknown
            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>

[Bug analyzer/101503] [12 Regression] ICE in involves_p, at analyzer/svalue.cc:557

[dmalcolm at gcc dot gnu.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101503

David Malcolm <dmalcolm at gcc dot gnu.org> changed:

           What    |Removed                     |Added
----------------------------------------------------------------------------
             Status|ASSIGNED                    |RESOLVED
         Resolution|---                         |FIXED

--- Comment #3 from David Malcolm <dmalcolm at gcc dot gnu.org> ---
Should be fixed by the above patch.