Commit Graph

3523 Commits

Author SHA1 Message Date
Artem Dergachev 851e95c1c1 [analyzer] Fix the 'analyzer-enabled-checkers.c' test on non-linux machines.
'-Xclang -triple' doesn't seem to override the default target triple
as reliably as '--target'. This leads to test failing due to
platform-specific checks getting unexpectedly enabled.

llvm-svn: 371781
2019-09-12 22:11:15 +00:00
Kristof Umann d977b67ed6 [analyzer] Don't run the analyzer for -analyzer-list-enabled-checkers
Short and sweet. Whenever I use -analyzer-list-enabled-checkers, I'm only
interested about the configuration, not about the analysis.

Differential Revision: https://reviews.llvm.org/D66714

llvm-svn: 371756
2019-09-12 18:53:48 +00:00
Reid Kleckner 38e033bf33 Re-land Remove REQUIRES:shell from tests that pass for me on Windows
This reverts r371497 (git commit 3d7e9ab7b9)

Reorder `not` with `env` in these two tests so they pass:
  Driver/rewrite-map-in-diagnostics.c
  Index/crash-recovery-modules.m.

This will not be necessary after D66531 lands.

llvm-svn: 371552
2019-09-10 20:15:45 +00:00
James Henderson 3d7e9ab7b9 Revert Remove REQUIRES:shell from tests that pass for me on Windows
This reverts r371478 (git commit a9980f60ce)

llvm-svn: 371497
2019-09-10 08:48:33 +00:00
Reid Kleckner a9980f60ce Remove REQUIRES:shell from tests that pass for me on Windows
I see in the history for some of these tests REQUIRES:shell was used as
a way to disable tests on Windows because they are flaky there. I tried
not to re-enable such tests, but it's possible that I missed some and
this will re-enable flaky tests on Windows. If so, we should disable
them with UNSUPPORTED:system-windows and add a comment that they are
flaky there. So far as I can tell, the lit internal shell is capable of
running all of these tests, and we shouldn't use REQUIRES:shell as a
proxy for Windows.

llvm-svn: 371478
2019-09-10 00:50:32 +00:00
Gabor Borsik 080ecafdd8 Move prop-sink branch to monorepo.
llvm-svn: 371342
2019-09-08 19:23:43 +00:00
Artem Dergachev 6cee434ed1 [analyzer] Add minimal support for fix-it hints.
Allow attaching fixit hints to Static Analyzer BugReports.

Fixits are attached either to the bug report itself or to its notes
(path-sensitive event notes or path-insensitive extra notes).

Add support for fixits in text output (including the default text output that
goes without notes, as long as the fixit "belongs" to the warning).

Add support for fixits in the plist output mode.

Implement a fixit for the path-insensitive DeadStores checker. Only dead
initialization warning is currently covered.

Implement a fixit for the path-sensitive VirtualCall checker when the virtual
method is not pure virtual (in this case the "fix" is to suppress the warning
by qualifying the call).

Both fixits are under an off-by-default flag for now, because they
require more careful testing.

Differential Revision: https://reviews.llvm.org/D65182

llvm-svn: 371257
2019-09-06 20:55:29 +00:00
Artem Dergachev 2b1b4cab96 [analyzer] pr43179: Make CallDescription defensive against C variadic functions.
Most functions that our checkers react upon are not C-style variadic functions,
and therefore they have as many actual arguments as they have formal parameters.

However, it's not impossible to define a variadic function with the same name.
This will crash any checker that relies on CallDescription to check the number
of arguments but silently assumes that the number of parameters is the same.

Change CallDescription to check both the number of arguments and the number of
parameters by default.

If we're intentionally trying to match variadic functions, allow specifying
arguments and parameters separately (possibly omitting any of them).
For now we only have one CallDescription which would make use of those,
namely __builtin_va_start itself.

Differential Revision: https://reviews.llvm.org/D67019

llvm-svn: 371256
2019-09-06 20:55:24 +00:00
Kristof Umann 1b439659a8 [analyzer] NonNullParamChecker and CStringChecker parameter number in checker message
There are some functions which can't be given a null pointer as parameter either
because it has a nonnull attribute or it is declared to have undefined behavior
(e.g. strcmp()). Sometimes it is hard to determine from the checker message
which parameter is null at the invocation, so now this information is included
in the message.

This commit fixes https://bugs.llvm.org/show_bug.cgi?id=39358

Reviewed By: NoQ, Szelethus, whisperity

Patch by Tibor Brunner!

Differential Revision: https://reviews.llvm.org/D66333

llvm-svn: 370798
2019-09-03 17:57:01 +00:00
Kristof Umann 3b18b050b8 [analyzer] Add a checker option to detect nested dead stores
Enables the users to specify an optional flag which would warn for more dead
stores.
Previously it ignored if the dead store happened e.g. in an if condition.

if ((X = generate())) { // dead store to X
}

This patch introduces the `WarnForDeadNestedAssignments` option to the checker,
which is `false` by default - so this change would not affect any previous
users.
I have updated the code, tests and the docs as well. If I missed something, tell
me.

I also ran the analysis on Clang which generated 14 more reports compared to the
unmodified version. All of them seemed reasonable for me.

Related previous patches:
rGf224820b45c6847b91071da8d7ade59f373b96f3

Reviewers: NoQ, krememek, Szelethus, baloghadamsoftware

Reviewed By: Szelethus

Patch by Balázs Benics!

Differential Revision: https://reviews.llvm.org/D66733

llvm-svn: 370767
2019-09-03 15:22:43 +00:00
Richard Smith 5030928d60 [c++20] Implement semantic restrictions for C++20 designated
initializers.

This has some interesting interactions with our existing extensions to
support C99 designated initializers as an extension in C++. Those are
resolved as follows:

 * We continue to permit the full breadth of C99 designated initializers
   in C++, with the exception that we disallow a partial overwrite of an
   initializer with a non-trivially-destructible type. (Full overwrite
   is OK, because we won't run the first initializer at all.)

 * The C99 extensions are disallowed in SFINAE contexts and during
   overload resolution, where they could change the meaning of valid
   programs.

 * C++20 disallows reordering of initializers. We only check for that for
   the simple cases that the C++20 rules permit (designators of the form
   '.field_name =' and continue to allow reordering in other cases).
   It would be nice to improve this behavior in future.

 * All C99 designated initializer extensions produce a warning by
   default in C++20 mode. People are going to learn the C++ rules based
   on what Clang diagnoses, so it's important we diagnose these properly
   by default.

 * In C++ <= 17, we apply the C++20 rules rather than the C99 rules, and
   so still diagnose C99 extensions as described above. We continue to
   accept designated C++20-compatible initializers in C++ <= 17 silently
   by default (but naturally still reject under -pedantic-errors).

This is not a complete implementation of P0329R4. In particular, that
paper introduces new non-C99-compatible syntax { .field { init } }, and
we do not support that yet.

This is based on a previous patch by Don Hinton, though I've made
substantial changes when addressing the above interactions.

Differential Revision: https://reviews.llvm.org/D59754

llvm-svn: 370544
2019-08-30 22:52:55 +00:00
Artem Dergachev e5c0994ddf [CFG] Fix CFG for statement-expressions in return values.
We're building the CFG from bottom to top, so when the return-value expression
has a non-trivial CFG on its own, we need to continue building from the entry
to the return-value expression CFG rather than from the block to which
we've just appended the return statement.

Fixes a false positive warning "control may reach end of non-void function".

llvm-svn: 370406
2019-08-29 20:37:28 +00:00
Adam Balogh 12f5c7f0c3 [Analyzer] Iterator Checkers - Make range errors and invalidated access fatal
Range errors (dereferencing or incrementing the past-the-end iterator or
decrementing the iterator of the first element of the range) and access of
invalidated iterators lead to undefined behavior. There is no point to
continue the analysis after such an error on the same execution path, but
terminate it by a sink node (fatal error). This also improves the
performance and helps avoiding double reports (e.g. in case of nested
iterators).

Differential Revision: https://reviews.llvm.org/D62893

llvm-svn: 370314
2019-08-29 09:35:47 +00:00
Artem Dergachev ead98ea3eb [CFG] Make representation of destructor calls more accurate.
Respect C++17 copy elision; previously it would generate destructor calls
for elided temporaries, including in initialization and return statements.

Don't generate duplicate destructor calls for statement expressions.

Fix destructors in initialization lists and comma operators.

Improve printing of implicit destructors.

Patch by Nicholas Allegra!

Differential Revision: https://reviews.llvm.org/D66404

llvm-svn: 370247
2019-08-28 18:44:42 +00:00
Artem Dergachev 630f7daf80 [analyzer] Fix analyzer warnings on analyzer.
Write tests for the actual crash that was found. Write comments and refactor
code around 17 style bugs and suppress 3 false positives.

Differential Revision: https://reviews.llvm.org/D66847

llvm-svn: 370246
2019-08-28 18:44:38 +00:00
Artem Dergachev 0909a392f3 [analyzer] pr43036: Fix support for operator 'sizeof...'.
It was known to be a compile-time constant so it wasn't evaluated during
symbolic execution, but it wasn't evaluated as a compile-time constant either.

Differential Revision: https://reviews.llvm.org/D66565

llvm-svn: 370245
2019-08-28 18:44:35 +00:00
Artem Dergachev 8b2a39e937 [analyzer] Trust global initializers when analyzing main().
If the global variable has an initializer, we'll ignore it because we're usually
not analyzing the program from the beginning, which means that the global
variable may have changed before we start our analysis.

However when we're analyzing main() as the top-level function, we can rely
on global initializers to still be valid. At least in C; in C++ we have global
constructors that can still break this logic.

This patch allows the Static Analyzer to load constant initializers from
global variables if the top-level function of the current analysis is main().

Differential Revision: https://reviews.llvm.org/D65361

llvm-svn: 370244
2019-08-28 18:44:32 +00:00
Alexey Bataev 94a170f811 [OPENMP][Analysis] Add analysis of the map clauses.
Summary:
Added basic analysis of map clauses. Only map clauses with to and tofrom
map type must be analyzed since all other map types (alloc, delete, etc.) do not require to use the value of the initial variable, instead they create the new copy of the variable.

Reviewers: NoQ

Subscribers: guansong, cfe-commits, kkwli0, caomhin

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66668

llvm-svn: 370214
2019-08-28 14:55:08 +00:00
Joe Ranieri fce4324f92 Update the SARIF exporter to SARIF 2.1
This updates the SARIF exporter to produce SARIF 2.1 output. The bulk of the diffs come from two changes to SARIF:
* https://github.com/oasis-tcs/sarif-spec/issues/309
* https://github.com/oasis-tcs/sarif-spec/issues/179

Differential Revision: https://reviews.llvm.org/D65211

llvm-svn: 370068
2019-08-27 14:43:54 +00:00
Joe Ranieri 3385c5cc4d Fix a SARIF exporter crash with macro expansions
Differential Revision: https://reviews.llvm.org/D65209

llvm-svn: 370061
2019-08-27 14:20:27 +00:00
Joe Ranieri 68a6a28ef8 Fix text range end columns in SARIF to be exclusive
According to the SARIF specification, "a text region does not include the character specified by endColumn".

Differential Revision: https://reviews.llvm.org/D65206

llvm-svn: 370060
2019-08-27 13:49:45 +00:00
Gabor Marton f035b75d8f [ASTImporter] Fix name conflict handling with different strategies
There are numorous flaws about the name conflict handling, this patch
attempts fixes them. Changes in details:

* HandleNameConflict return with a false DeclarationName

Hitherto we effectively never returned with a NameConflict error, even
if the preceding StructuralMatch indicated a conflict.
Because we just simply returned with the parameter `Name` in
HandleNameConflict and that name is almost always `true` when converted to
`bool`.

* Add tests which indicate wrong NameConflict handling

* Add to ConflictingDecls only if decl kind is different

Note, we might not indicate an ODR error when there is an existing record decl
and a enum is imported with same name.  But there are other cases. E.g. think
about the case when we import a FunctionTemplateDecl with name f and we found a
simple FunctionDecl with name f. They overload.  Or in case of a
ClassTemplateDecl and CXXRecordDecl, the CXXRecordDecl could be the 'templated'
class, so it would be false to report error.  So I think we should report a
name conflict error only when we are 100% sure of that.  That is why I think it
should be a general pattern to report the error only if the kind is the same.

* Fix failing ctu test with EnumConstandDecl

In ctu-main.c we have the enum class 'A' which brings in the enum
constant 'x' with value 0 into the global namespace.
In ctu-other.c we had the enum class 'B' which brought in the same name
('x') as an enum constant but with a different enum value (42). This is clearly
an ODR violation in the global namespace. The solution was to rename the
second enum constant.

 * Introduce ODR handling strategies

Reviewers: a_sidorin, shafik

Differential Revision: https://reviews.llvm.org/D59692

llvm-svn: 370045
2019-08-27 11:36:10 +00:00
Kristof Umann 09ce8ec78a [analyzer] Avoid unnecessary enum range check on LValueToRValue casts
Summary: EnumCastOutOfRangeChecker should not perform enum range checks on LValueToRValue casts, since this type of cast does not actually change the underlying type.   Performing the unnecessary check actually triggered an assertion failure deeper in EnumCastOutOfRange for certain input (which is captured in the accompanying test code).

Reviewers: #clang, Szelethus, gamesh411, NoQ

Reviewed By: Szelethus, gamesh411, NoQ

Subscribers: NoQ, gamesh411, xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, donat.nagy, dkrupp, Charusso, bjope, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D66014

llvm-svn: 369760
2019-08-23 14:21:13 +00:00
Artem Dergachev 85f7294e5a [analyzer] CastValueChecker: Correctly model results of based-to-derived casts.
Our SVal hierarchy doesn't allow modeling pointer casts as no-op. The
pointer type is instead encoded into the pointer object. Defer to our
usual pointer casting facility, SValBuilder::evalBinOp().

Fixes a crash.

llvm-svn: 369729
2019-08-23 03:24:04 +00:00
Artem Dergachev 62a76d0ae3 [analyzer] CastValueChecker: Provide DynamicTypeMap with pointer types only.
The idea to drop this requirement is good, but for now every other user
of DynamicTypeInfo expects pointer types.

Fixes a crash.

llvm-svn: 369728
2019-08-23 03:24:01 +00:00
Artem Dergachev af992e6d01 [analyzer] CastValueChecker: Avoid modeling casts between objects.
Our method only works correctly when casting a pointer to a pointer
or a reference to a reference.

Fixes a crash.

llvm-svn: 369727
2019-08-23 03:23:58 +00:00
Artem Dergachev 0900b77db2 [analyzer] DynamicTypeInfo: Avoid putting null regions into dynamic typemap.
Fixes a crash.

llvm-svn: 369726
2019-08-23 03:23:55 +00:00
Kristof Umann 0f9e530c0f [analyzer] Enable control dependency condition tracking by default
This patch concludes my GSoC'19 project by enabling track-conditions by default.

Differential Revision: https://reviews.llvm.org/D66381

llvm-svn: 369616
2019-08-22 03:08:48 +00:00
Csaba Dabis 4d71600c11 [analyzer] CastValueChecker: Model isa(), isa_and_nonnull()
Summary: -

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D66423

llvm-svn: 369615
2019-08-22 02:57:59 +00:00
Kristof Umann 58eb033a49 [analyzer] Don't track the condition of foreach loops
As discussed on the mailing list, notes originating from the tracking of foreach
loop conditions are always meaningless.

Differential Revision: https://reviews.llvm.org/D66131

llvm-svn: 369613
2019-08-22 02:44:19 +00:00
Csaba Dabis 0202c3596c [analyzer] CastValueChecker: Store the dynamic types and casts
Summary:
This patch introduces `DynamicCastInfo` similar to `DynamicTypeInfo` which
is stored in `CastSets` which are storing the dynamic cast informations of
objects based on memory regions. It could be used to store and check the
casts and prevent infeasible paths.

Reviewed By: NoQ

Differential Revision: https://reviews.llvm.org/D66325

llvm-svn: 369605
2019-08-22 00:20:36 +00:00
Csaba Dabis b73a5711f6 [analyzer] TrackConstraintBRVisitor: Do not track unknown values
Summary: -

Reviewers: NoQ, Szelethus

Reviewed By: NoQ, Szelethus

Differential Revision: https://reviews.llvm.org/D66267

llvm-svn: 369604
2019-08-22 00:06:58 +00:00
Kristof Umann d9a81ccf05 [analyzer] Mention whether an event is about a condition in a bug report part 2
In D65724, I do a pretty thorough explanation about how I'm solving this
problem, I think that summary nails whats happening here ;)

Differential Revision: https://reviews.llvm.org/D65725

llvm-svn: 369596
2019-08-21 22:38:00 +00:00
Kristof Umann 49ac7ece16 [analyzer] Don't make ConditionBRVisitor events prunable when the condition is an interesting field
Exactly what it says on the tin! Note that we're talking about interestingness
in general, hence this isn't a control-dependency-tracking specific patch.

Differential Revision: https://reviews.llvm.org/D65724

llvm-svn: 369589
2019-08-21 21:59:22 +00:00
Kristof Umann da648ab8de [analyzer] Mention whether an event is about a condition in a bug report part 1
Can't add much more to the title! This is part 1, the case where the collapse
point isn't in the condition point is the responsibility of ConditionBRVisitor,
which I'm addressing in part 2.

Differential Revision: https://reviews.llvm.org/D65575

llvm-svn: 369574
2019-08-21 20:43:27 +00:00
Artem Dergachev 8eb7a74b78 [analyzer] Fix a crash when destroying a non-region.
Add defensive check that prevents a crash when we try to evaluate a destructor
whose this-value is a concrete integer that isn't a null.

Differential Revision: https://reviews.llvm.org/D65349

llvm-svn: 369450
2019-08-20 21:41:17 +00:00
Artem Dergachev d3971fe97b [analyzer] Improve VirtualCallChecker and enable parts of it by default.
Calling a pure virtual method during construction or destruction
is undefined behavior. It's worth it to warn about it by default.
That part is now known as the cplusplus.PureVirtualCall checker.

Calling a normal virtual method during construction or destruction
may be fine, but does behave unexpectedly, as it skips virtual dispatch.
Do not warn about this by default, but let projects opt in into it
by enabling the optin.cplusplus.VirtualCall checker manually.

Give the two parts differentiated warning text:

  Before:

    Call to virtual function during construction or destruction:
    Call to pure virtual function during construction

    Call to virtual function during construction or destruction:
    Call to virtual function during destruction

  After:

    Pure virtual method call:
    Call to pure virtual method 'X::foo' during construction
        has undefined behavior

    Unexpected loss of virtual dispatch:
    Call to virtual method 'Y::bar' during construction
        bypasses virtual dispatch

Also fix checker names in consumers that support them (eg., clang-tidy)
because we now have different checker names for pure virtual calls and
regular virtual calls.

Also fix capitalization in the bug category.

Differential Revision: https://reviews.llvm.org/D64274

llvm-svn: 369449
2019-08-20 21:41:14 +00:00
Artem Dergachev 8cf3dfea54 [CallGraph] Take into accound calls that aren't within any function bodies.
This patch improves Clang call graph analysis by adding in expressions
that are not found in regular function bodies, such as default arguments
or member initializers.

Patch by Joshua Cranmer!

Differential Revision: https://reviews.llvm.org/D65453

llvm-svn: 369321
2019-08-20 02:22:37 +00:00
Kristof Umann 032e1fdcd4 [analyzer] Turn an assert into an if condition
Shocker, turns out that terminator conditions that are binary operators
aren't always logical operators.

llvm-svn: 369195
2019-08-17 16:49:54 +00:00
Balazs Keri e13e836480 [ASTImporter] Import ctor initializers after setting flags.
Summary:
Code to import "ctor initializers" at import of functions
is moved to be after the flags in the newly created function
are imported. This fixes an error when the already created but
incomplete (flags are not set) function declaration is accessed.

Reviewers: martong, shafik, a_sidorin, a.sidorin

Reviewed By: shafik

Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D65935

llvm-svn: 369098
2019-08-16 12:10:03 +00:00
Csaba Dabis a079a42708 [analyzer] Analysis: Silence checkers
Summary:
This patch introduces a new `analyzer-config` configuration:
`-analyzer-config silence-checkers`
which could be used to silence the given checkers.

It accepts a semicolon separated list, packed into quotation marks, e.g:
`-analyzer-config silence-checkers="core.DivideZero;core.NullDereference"`

It could be used to "disable" core checkers, so they model the analysis as
before, just if some of them are too noisy it prevents to emit reports.

This patch also adds support for that new option to the scan-build.
Passing the option `-disable-checker core.DivideZero` to the scan-build
will be transferred to `-analyzer-config silence-checkers=core.DivideZero`.

Reviewed By: NoQ, Szelethus

Differential Revision: https://reviews.llvm.org/D66042

llvm-svn: 369078
2019-08-16 01:53:14 +00:00
Kristof Umann 571c52af58 [analyzer][NFC] Prove that we only track the evaluated part of the condition
...because we're working with a BugReporterVisitor, and the non-evaluated part
of the condition isn't in the bugpath.

Differential Revision: https://reviews.llvm.org/D65290

llvm-svn: 368853
2019-08-14 13:51:52 +00:00
Kristof Umann dd53bdbfde [analyzer][CFG] Don't track the condition of asserts
Well, what is says on the tin I guess!

Some more changes:

* Move isInevitablySinking() from BugReporter.cpp to CFGBlock's interface
* Rename and move findBlockForNode() from BugReporter.cpp to
ExplodedNode::getCFGBlock()

Differential Revision: https://reviews.llvm.org/D65287

llvm-svn: 368836
2019-08-14 12:20:08 +00:00
Balazs Keri c509594319 [ASTImporter] Import default expression of param before creating the param.
Summary:
The default expression of a parameter variable should be imported before
the parameter variable object is created. Otherwise the function is created
with an incomplete parameter variable (default argument is nullptr) and in
this intermediary state the expression is imported. This import can have
a reference to the incomplete parameter variable that causes crash.

Reviewers: martong, a.sidorin, shafik

Reviewed By: martong

Subscribers: rnkovacs, dkrupp, Szelethus, gamesh411, cfe-commits

Tags: #clang

Differential Revision: https://reviews.llvm.org/D65577

llvm-svn: 368818
2019-08-14 09:41:39 +00:00
Kristof Umann 967583bc08 [analyzer] Note last writes to a condition only in a nested stackframe
Exactly what it says on the tin! The comments in the code detail this a
little more too.

Differential Revision: https://reviews.llvm.org/D64272

llvm-svn: 368817
2019-08-14 09:39:38 +00:00
Kristof Umann 0df9c8c578 [analyzer] Track the right hand side of the last store regardless of its value
Summary:
The following code snippet taken from D64271#1572188 has an issue: namely,
because `flag`'s value isn't undef or a concrete int, it isn't being tracked.

int flag;
bool coin();

void foo() {
  flag = coin();
}

void test() {
  int *x = 0;
  int local_flag;
  flag = 1;

  foo();
  local_flag = flag;
  if (local_flag)
    x = new int;

  foo();
  local_flag = flag;
  if (local_flag)
    *x = 5;
}

This, in my opinion, makes no sense, other values may be interesting too.
Originally added by rC185608.

Differential Revision: https://reviews.llvm.org/D64287

llvm-svn: 368773
2019-08-13 23:48:10 +00:00
Kristof Umann 46929df723 [analyzer] Prune calls to functions with linear CFGs that return a non-zero constrained value
During the evaluation of D62883, I noticed a bunch of totally
meaningless notes with the pattern of "Calling 'A'" -> "Returning value"
-> "Returning from 'A'", which added no value to the report at all.

This patch (not only affecting tracked conditions mind you) prunes
diagnostic messages to functions that return a value not constrained to
be 0, and are also linear.

Differential Revision: https://reviews.llvm.org/D64232

llvm-svn: 368771
2019-08-13 23:22:33 +00:00
Artem Dergachev daf41722bd [analyzer] exploded-graph-rewriter: Implement displaying Store pointers.
They're useful when trying to understand what's going on
inside your LazyCompoundValues.

Differential Revision: https://reviews.llvm.org/D65427

llvm-svn: 368769
2019-08-13 23:04:56 +00:00
Artem Dergachev 9289681ea3 [analyzer] exploded-graph-rewriter: Implement manual graph trimming.
When -trim-egraph is unavailable (say, when you're debugging a crash on
a real-world code that takes too long to reduce), it makes sense to view
the untrimmed graph up to the crashing node's predecessor, then dump the ID
(or a pointer) of the node in the attached debugger, and then trim
the dumped graph in order to keep only paths from the root to the node.

The newly added --to flag does exactly that:

$ exploded-graph-rewriter.py ExprEngine.dot --to 0x12229acd0

Multiple nodes can be specified. Stable IDs of nodes can be used
instead of pointers.

Differential Revision: https://reviews.llvm.org/D65345

llvm-svn: 368768
2019-08-13 23:04:53 +00:00
Artem Dergachev 0b26891f3f [analyzer] exploded-graph-rewriter: NFC: Refactor explorers into trimmers.
Explorers aren't the right abstraction. For the purposes of displaying svg files
we don't care in which order do we explore the nodes. We may care about this for
other analyses, but we're not there yet.

The function of cutting out chunks of the graph is performed poorly by
the explorers, because querying predecessors/successors on the explored nodes
yields original successors/predecessors even if they aren't being explored.

Introduce a new entity, "trimmers", that do one thing but to it right: cut out
chunks of the graph. Trimmers mutate the graph, so stale edges aren't even
visible to their consumers in the pipeline. Additionally, trimmers are
intrinsically composable: multiple trimmers can be applied to the graph
sequentially.

Refactor the single-path explorer into the single-path trimmer.
Rename the test file for consistency.

Differential Revision: https://reviews.llvm.org/D65344

llvm-svn: 368767
2019-08-13 23:04:50 +00:00