Commit Graph

4 Commits

Author SHA1 Message Date
Joel E. Denny 6fc21c2522 [FileCheck] Fix search ranges for DAG-NOT-DAG
A DAG-NOT-DAG is a CHECK-DAG group, X, followed by a CHECK-NOT group,
N, followed by a CHECK-DAG group, Y.  Let y be the initial directive
of Y.  This patch makes the following changes to the behavior:

    1. Directives in N can no longer match within part of Y's match
       range just because y happens not to be the earliest match from
       Y.  Specifically, this patch withdraws N's search range end
       from y's match range start to Y's match range start.

    2. y can no longer match within X's match range, where a y match
       produced a reordering complaint, which is thus no longer
       possible.  Specifically, this patch withdraws y's search range
       start from X's permitted range start to X's match range end,
       which was already the search range start for other members of
       Y.

Both of these changes can only increase the number of test passes: #1
constrains the ability of CHECK-NOTs to match, and #2 expands the
ability of CHECK-DAGs to match without complaints.

These changes are based on discussions at:

   <http://lists.llvm.org/pipermail/llvm-dev/2018-May/123550.html>
   <https://reviews.llvm.org/D47106>

which conclude that:

    1. These changes simplify the FileCheck conceptual model.  First,
       it makes search ranges for DAG-NOT-DAG more consistent with
       other cases.  Second, it was confusing that y was treated
       differently from the rest of Y.

    2. These changes add theoretical use cases for DAG-NOT-DAG that
       had no obvious means to be expressed otherwise.  We can justify
       the first half of this assertion with the observation that
       these changes can only increase the number of test passes.

    3. Reordering detection for DAG-NOT-DAG had no obvious real
       benefit.

We don't have evidence from real uses cases to help us debate
conclusions #2 and #3, but #1 at least seems intuitive.

Reviewed By: probinson

Differential Revision: https://reviews.llvm.org/D48986

llvm-svn: 337605
2018-07-20 20:09:56 +00:00
Joel E. Denny bcf5b441d8 [FileCheck] Don't permit overlapping CHECK-DAG
That is, make CHECK-DAG skip matches that overlap the matches of any
preceding consecutive CHECK-DAG directives.  This change makes
CHECK-DAG more consistent with other directives, and there is evidence
it makes CHECK-DAG more intuitive and less error-prone.  See the RFC
discussion starting at:

  http://lists.llvm.org/pipermail/llvm-dev/2018-May/123010.html

Moreover, this behavior enables CHECK-DAG groups for unordered,
non-unique strings or patterns.  For example, it is useful for
verifying output or logs from a parallel program, such as the OpenMP
runtime.

This patch also implements the command-line option
-allow-deprecated-dag-overlap, which reverts CHECK-DAG to the old
overlapping behavior.  This option should not be used in new tests.
It is meant only for the existing tests that are broken by this change
and that need time to update.

See the following bugzilla issue for tracking of such tests:

  https://bugs.llvm.org/show_bug.cgi?id=37532

Patches to add -allow-deprecated-dag-overlap to those tests will
follow immediately.

Reviewed By: probinson

Differential Revision: https://reviews.llvm.org/D47106

llvm-svn: 336847
2018-07-11 20:27:27 +00:00
Joel E. Denny 614c986175 Revert r336830: [FileCheck] Don't permit overlapping CHECK-DAG
Companion patches are failing to commit, and this patch alone breaks
many tests.

llvm-svn: 336833
2018-07-11 19:03:00 +00:00
Joel E. Denny edf338856c [FileCheck] Don't permit overlapping CHECK-DAG
That is, make CHECK-DAG skip matches that overlap the matches of any
preceding consecutive CHECK-DAG directives.  This change makes
CHECK-DAG more consistent with other directives, and there is evidence
it makes CHECK-DAG more intuitive and less error-prone.  See the RFC
discussion starting at:

  http://lists.llvm.org/pipermail/llvm-dev/2018-May/123010.html

Moreover, this behavior enables CHECK-DAG groups for unordered,
non-unique strings or patterns.  For example, it is useful for
verifying output or logs from a parallel program, such as the OpenMP
runtime.

This patch also implements the command-line option
-allow-deprecated-dag-overlap, which reverts CHECK-DAG to the old
overlapping behavior.  This option should not be used in new tests.
It is meant only for the existing tests that are broken by this change
and that need time to update.

See the following bugzilla issue for tracking of such tests:

  https://bugs.llvm.org/show_bug.cgi?id=37532

Patches to add -allow-deprecated-dag-overlap to those tests will
follow immediately.

Reviewed By: probinson

Differential Revision: https://reviews.llvm.org/D47106

llvm-svn: 336830
2018-07-11 18:42:58 +00:00