Commit Graph

54 Commits

Author SHA1 Message Date
Artem Dergachev 69ece336b8 [analyzer] Fix a crash on casting symbolic pointers to derived classes.
Commit r340984 causes a crash when a pointer to a completely unrelated type
UnrelatedT (eg., opaque struct pattern) is being casted from base class BaseT to
derived class DerivedT, which results in an ill-formed region
Derived{SymRegion{$<UnrelatedT x>}, DerivedT}.

Differential Revision: https://reviews.llvm.org/D52189

llvm-svn: 343051
2018-09-26 00:17:14 +00:00
Artem Dergachev 4e864b8329 [analyzer] Support modeling no-op BaseToDerived casts in ExprEngine.
Introduce a new MemRegion sub-class, CXXDerivedObjectRegion, which is
the opposite of CXXBaseObjectRegion, to represent such casts. Such region is
a bit weird because it is by design bigger than its super-region.
But it's not harmful when it is put on top of a SymbolicRegion
that has unknown extent anyway.

Offset computation for CXXDerivedObjectRegion and proper modeling of casts
still remains to be implemented.

Differential Revision: https://reviews.llvm.org/D51191

llvm-svn: 340984
2018-08-29 22:43:31 +00:00
Fangrui Song 6907ce2f8f Remove trailing space
sed -Ei 's/[[:space:]]+$//' include/**/*.{def,h,td} lib/**/*.{cpp,h}

llvm-svn: 338291
2018-07-30 19:24:48 +00:00
Artem Dergachev e603e076f5 [analyzer] pr36458: Fix retrieved value cast for symbolic void pointers.
C allows us to write any bytes into any memory region. When loading weird bytes
from memory regions of known types, the analyzer is required to make sure that
the loaded value makes sense by casting it to an appropriate type.

Fix such cast for loading values that represent void pointers from non-void
pointer type places.

Differential Revision: https://reviews.llvm.org/D46415

llvm-svn: 331562
2018-05-04 22:11:12 +00:00
Artem Dergachev 806486c781 [analyzer] pr18953: Split C++ zero-initialization from default initialization.
The bindDefault() API of the ProgramState allows setting a default value
for reads from memory regions that were not preceded by writes.

It was used for implementing C++ zeroing constructors (i.e. default constructors
that boil down to setting all fields of the object to 0).

Because differences between zeroing consturctors and other forms of default
initialization have been piling up (in particular, zeroing constructors can be
called multiple times over the same object, probably even at the same offset,
requiring a careful and potentially slow cleanup of previous bindings in the
RegionStore), we split the API in two: bindDefaultInitial() for modeling
initial values and bindDefaultZero() for modeling zeroing constructors.

This fixes a few assertion failures from which the investigation originated.

The imperfect protection from both inability of the RegionStore to support
binding extents and lack of information in ASTRecordLayout has been loosened
because it's, well, imperfect, and it is unclear if it fixing more than it
was breaking.

Differential Revision: https://reviews.llvm.org/D46368

llvm-svn: 331561
2018-05-04 21:56:51 +00:00
Artem Dergachev 4cc0d4e823 [analyzer] NFC: Remove unused parameteer of StoreManager::CastRetrievedVal().
llvm-svn: 331496
2018-05-04 00:53:41 +00:00
Alexander Kornienko 2a8c18d991 Fix typos in clang
Found via codespell -q 3 -I ../clang-whitelist.txt
Where whitelist consists of:

  archtype
  cas
  classs
  checkk
  compres
  definit
  frome
  iff
  inteval
  ith
  lod
  methode
  nd
  optin
  ot
  pres
  statics
  te
  thru

Patch by luzpaz! (This is a subset of D44188 that applies cleanly with a few
files that have dubious fixes reverted.)

Differential revision: https://reviews.llvm.org/D44188

llvm-svn: 329399
2018-04-06 15:14:32 +00:00
Eugene Zelenko e029a2ff23 [StaticAnalyzer] Fix some Clang-tidy modernize and Include What You Use warnings; other minor fixes (NFC).
llvm-svn: 326633
2018-03-02 23:11:49 +00:00
Alexander Shaposhnikov 9a21d28b5d [analyzer] Fix handling of labels in getLValueElement
In getLValueElement Base may represent the address of a label 
(as in the newly-added test case), in this case it's not a loc::MemRegionVal 
and Base.castAs<loc::MemRegionVal>() triggers an assert, this diff makes 
getLValueElement return UnknownVal instead.

Differential revision: https://reviews.llvm.org/D39174

llvm-svn: 316399
2017-10-23 23:46:06 +00:00
Artem Dergachev 37de888867 [analyzer] Improve suppression for inlined defensive checks before operator &.
Null dereferences are suppressed if the lvalue was constrained to 0 for the
first time inside a sub-function that was inlined during analysis, because
such constraint is a valid defensive check that does not, by itself,
indicate that null pointer case is anyhow special for the caller.

If further operations on the lvalue are performed, the symbolic lvalue is
collapsed to concrete null pointer, and we need to track where does the null
pointer come from.

Improve such tracking for lvalue operations involving operator &.

rdar://problem/27876009

Differential Revision: https://reviews.llvm.org/D31982

llvm-svn: 301224
2017-04-24 19:30:33 +00:00
Artem Dergachev 6dd11048f5 [analyzer] Enforce super-region classes for various memory regions.
We now check the type of the super-region pointer for most SubRegion classes
in compile time; some checks are run-time though.

This is an API-breaking change (we now require explicit casts to specific region
sub-classes), but in practice very few checkers are affected.

Differential Revision: https://reviews.llvm.org/D26838

llvm-svn: 300189
2017-04-13 09:56:07 +00:00
Gabor Horvath 44583ce65a [analyzer] Model base to derived casts more precisely.
Dynamic casts are handled relatively well by the static analyzer.
BaseToDerived casts however are treated conservatively. This can cause some
false positives with the NewDeleteLeaks checker.

This patch alters the behavior of BaseToDerived casts. In case a dynamic cast
would succeed use the same semantics. Otherwise fall back to the conservative
approach.

Differential Revision: https://reviews.llvm.org/D23014

llvm-svn: 277989
2016-08-08 09:22:59 +00:00
Artem Dergachev 73f018e381 [analyzer] Fix SVal/SymExpr/MemRegion class and enum names for consistency.
The purpose of these changes is to simplify introduction of definition files
for the three hierarchies.

1. For every sub-class C of these classes, its kind in the relevant enumeration
is changed to "CKind" (or C##Kind in preprocessor-ish terms), eg:

  MemRegionKind   -> MemRegionValKind
  RegionValueKind -> SymbolRegionValueKind
  CastSymbolKind  -> SymbolCastKind
  SymIntKind      -> SymIntExprKind

2. MemSpaceRegion used to be inconsistently used as both an abstract base and
a particular region. This region class is now an abstract base and no longer
occupies GenericMemSpaceRegionKind. Instead, a new class, CodeSpaceRegion,
is introduced for handling the unique use case for MemSpaceRegion as
"the generic memory space" (when it represents a memory space that holds all
executable code).

3. BEG_ prefixes in memory region kind ranges are renamed to BEGIN_ for
consisitency with symbol kind ranges.

4. FunctionTextRegion and BlockTextRegion are renamed to FunctionCodeRegion and
BlockCodeRegion, respectively. The term 'code' is less jargony than 'text' and
we already refer to BlockTextRegion as a 'code region' in BlockDataRegion.

Differential Revision: http://reviews.llvm.org/D16062

llvm-svn: 257598
2016-01-13 13:49:29 +00:00
Angel Garcia Gomez 637d1e6694 Roll-back r250822.
Summary: It breaks the build for the ASTMatchers

Subscribers: klimek, cfe-commits

Differential Revision: http://reviews.llvm.org/D13893

llvm-svn: 250827
2015-10-20 13:23:58 +00:00
Angel Garcia Gomez b5250d3448 Apply modernize-use-default to clang.
Summary: Replace empty bodies of default constructors and destructors with '= default'.

Reviewers: bkramer, klimek

Subscribers: klimek, alexfh, cfe-commits

Differential Revision: http://reviews.llvm.org/D13890

llvm-svn: 250822
2015-10-20 12:52:55 +00:00
Ted Kremenek 3a0678e33c [analyzer] Apply whitespace cleanups by Honggyu Kim.
llvm-svn: 246978
2015-09-08 03:50:52 +00:00
Anna Zaks 0820e13e2a [analyzer] Refactor and cleanup IsCompleteType
There are three copies of IsCompleteType(...) functions in CSA and all
of them are incomplete (I experienced  crashes in some CSA's test cases).
I have replaced these function calls with Type::isIncompleteType() calls.

A patch by Aleksei Sidorin!

llvm-svn: 219026
2014-10-03 21:49:03 +00:00
Craig Topper 0dbb783c7b [C++11] Use 'nullptr'. StaticAnalyzer edition.
llvm-svn: 209642
2014-05-27 02:45:47 +00:00
Pavel Labath cb0b876b39 Fix static analyzer crash when casting from an incomplete type
Summary:
When doing a reinterpret+dynamic cast from an incomplete type, the analyzer
would crash (bug #16308). This fix makes the dynamic cast evaluator ignore
incomplete types, as they can never be used in a dynamic_cast. Also adding a
regression test.

CC: cfe-commits

Differential Revision: http://llvm-reviews.chandlerc.com/D1006

llvm-svn: 184403
2013-06-20 07:45:01 +00:00
Jordan Rose b957113b3f [analyzer] Treat reinterpret_cast like a base cast in certain cases.
The analyzer represents all pointer-to-pointer bitcasts the same way, but
this can be problematic if an implicit base cast gets layered on top of a
manual base cast (performed with reinterpret_cast instead of static_cast).
Fix this (and avoid a valid assertion) by looking through cast regions.

Using reinterpret_cast this way is only valid if the base class is at the
same offset as the derived class; this is checked by -Wreinterpret-base-class.
In the interest of performance, the analyzer doesn't repeat this check
anywhere; it will just silently do the wrong thing (use the wrong offsets
for fields of the base class) if the user code is wrong.

PR15394

llvm-svn: 180052
2013-04-22 21:36:49 +00:00
Jordan Rose 599f85ab85 [analyzer] Record whether a base object region represents a virtual base.
This allows MemRegion and MemRegionManager to avoid asking over and over
again whether an class is a virtual base or a non-virtual base.

Minor optimization/cleanup; no functionality change.

llvm-svn: 175716
2013-02-21 03:12:32 +00:00
David Blaikie 05785d1622 Include llvm::Optional in clang/Basic/LLVM.h
Post-commit CR feedback from Jordan Rose regarding r175594.

llvm-svn: 175679
2013-02-20 22:23:23 +00:00
David Blaikie 2fdacbc5b0 Replace SVal llvm::cast support to be well-defined.
See r175462 for another example/more details.

llvm-svn: 175594
2013-02-20 05:52:05 +00:00
Jordan Rose 5bc0dd79e1 [analyzer] Don't assert when mixing reinterpret_cast and derived-to-base casts.
This just adds a very simple check that if a DerivedToBase CastExpr is
operating on a value with known C++ object type, and that type is not the
base type specified in the AST, then the cast is invalid and we should
return UnknownVal.

In the future, perhaps we can have a checker that specifies that this is
illegal, but we still shouldn't assert even if the user turns that checker
off.

PR14872

llvm-svn: 175239
2013-02-15 01:23:24 +00:00
Chandler Carruth 3a02247dc9 Sort all of Clang's files under 'lib', and fix up the broken headers
uncovered.

This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.

I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.

llvm-svn: 169237
2012-12-04 09:13:33 +00:00
Jordan Rose 9aa9980217 [analyzer] Push evalDynamicCast and evalDerivedToBase up to Store.
These functions are store-agnostic, and would benefit from information in
DynamicTypeInfo but gain nothing from the store type.

No intended functionality change.

llvm-svn: 165078
2012-10-03 01:08:32 +00:00
Jordan Rose 996d309fb7 [analyzer] A CXXBaseObjectRegion should correspond to a DIRECT base.
An ASTContext's RecordLayoutInfo can only be used to look up offsets of
direct base classes, and we need the offset to make non-symbolic bindings
in RegionStore. This change makes sure that we have one layer of
CXXBaseObjectRegion for each base we are casting through.

This was causing crashes on an internal buildbot.

llvm-svn: 161621
2012-08-09 21:24:02 +00:00
Jordan Rose 3a80cec5e9 [analyzer] Revamp RegionStore to distinguish regions with symbolic offsets.
RegionStore currently uses a (Region, Offset) pair to describe the locations
of memory bindings. However, this representation breaks down when we have
regions like 'array[index]', where 'index' is unknown. We used to store this
as (SubRegion, 0); now we mark them specially as (SubRegion, SYMBOLIC).

Furthermore, ProgramState::scanReachableSymbols depended on the existence of
a sub-region map, but RegionStore's implementation doesn't provide for such
a thing. Moving the store-traversing logic of scanReachableSymbols into the
StoreManager allows us to eliminate the notion of SubRegionMap altogether.

This fixes some particularly awkward broken test cases, now in
array-struct-region.c.

llvm-svn: 161510
2012-08-08 18:23:27 +00:00
Jordan Rose 42e8d6497d [analyzer] Let CallEvent decide what goes in an inital stack frame.
This removes explicit checks for 'this' and 'self' from
Store::enterStackFrame. It also removes getCXXThisRegion() as a virtual
method on all CallEvents; it's now only implemented in the parts of the
hierarchy where it is relevant. Finally, it removes the option to ask
for the ParmVarDecls attached to the definition of an inlined function,
saving a recomputation of the result of getRuntimeDefinition().

No visible functionality change!

llvm-svn: 161017
2012-07-31 01:07:55 +00:00
Anna Zaks 63282aefb9 [analyzer] Very simple ObjC instance method inlining
- Retrieves the type of the object/receiver from the state.
- Binds self during stack setup.
- Only explores the path on which the method is inlined (no
bifurcation to explore the path on which the method is not inlined).

llvm-svn: 160991
2012-07-30 20:31:29 +00:00
Jordan Rose 4f7df9be69 [analyzer] Rename Calls.{h,cpp} to CallEvent.{h,cpp}. No functionality change.
llvm-svn: 160815
2012-07-26 21:39:41 +00:00
Jordan Rose eab627b951 [analyzer] Construct stack variables directly in their VarDecl.
Also contains a number of tweaks to inlining that are necessary
for constructors and destructors. (I have this enabled on a private
branch, but it is very much unstable.)

llvm-svn: 160023
2012-07-10 22:08:01 +00:00
Jordan Rose d1d54aa131 [analyzer] Use CallEvent for building inlined stack frames.
In order to accomplish this, we now build the callee's stack frame
as part of the CallEnter node, rather than the subsequent BlockEdge node.
This should not have any effect on perceived behavior or diagnostics.

This makes it safe to re-enable inlining of member overloaded operators.

llvm-svn: 160022
2012-07-10 22:07:57 +00:00
Anna Zaks 6797d6ee23 [analyser] Factor out FindUniqueBinding from RetainCount checker.
So that others could use it as well. No functionality change.

llvm-svn: 153211
2012-03-21 19:45:01 +00:00
Ted Kremenek 3bc5372fae [analyzer] teach analyzer about ObjC literals, thus trimming out a false positive with the malloc() checker involving
comparing literal addresses to nil.

Fixes <rdar://problem/10579586>

llvm-svn: 151602
2012-02-28 00:56:05 +00:00
Benjamin Kramer 11764ab4c0 StaticAnalyzer: Move ObjC- and CXX-specific methods out of line so checkers that don't care about the language don't have to pull in all the headers.
llvm-svn: 149178
2012-01-28 12:06:22 +00:00
Ted Kremenek 49b1e38e4b Change references to 'const ProgramState *' to typedef 'ProgramStateRef'.
At this point this is largely cosmetic, but it opens the door to replace
ProgramStateRef with a smart pointer that more eagerly acts in the role
of reclaiming unused ProgramState objects.

llvm-svn: 149081
2012-01-26 21:29:00 +00:00
Ted Kremenek 3d3aea9374 [analyzer] fix inlining's handling of mapping actual to formal arguments and limit the call stack depth. The analyzer can now accurately simulate factorial for limited depths.
llvm-svn: 148036
2012-01-12 19:25:46 +00:00
Anna Zaks 8158ef0dec [analyzer] Be less pessimistic about invalidation of global variables
as a result of a call.

Problem:
Global variables, which come in from system libraries should not be
invalidated by all calls. Also, non-system globals should not be
invalidated by system calls.

Solution:
The following solution to invalidation of globals seems flexible enough
for taint (does not invalidate stdin) and should not lead to too
many false positives. We split globals into 3 classes:

* immutable - values are preserved by calls (unless the specific
global is passed in as a parameter):
     A :  Most system globals and const scalars

* invalidated by functions defined in system headers:
     B: errno

* invalidated by all other functions (note, these functions may in
turn contain system calls):
     B: errno
     C: all other globals (which are not in A nor B)

llvm-svn: 147569
2012-01-04 23:54:01 +00:00
David Blaikie 68e081d606 Unweaken vtables as per http://llvm.org/docs/CodingStandards.html#ll_virtual_anch
llvm-svn: 146959
2011-12-20 02:48:34 +00:00
Anna Zaks c95a6c4c9f [analyzer] Address Jordy's comments for r145985.
llvm-svn: 146683
2011-12-15 21:33:26 +00:00
Anna Zaks c25efccc8b [analyzer] Propagate taint through NonLoc to NonLoc casts.
- Created a new SymExpr type - SymbolCast.
 - SymbolCast is created when we don't know how to simplify a NonLoc to
NonLoc casts.
 - A bit of code refactoring: introduced dispatchCast to have better
code reuse, remove a goto.
 - Updated the test case to showcase the new taint flow.

llvm-svn: 145985
2011-12-06 23:12:27 +00:00
David Blaikie aa347f9392 Removing a bunch of dead returns/breaks after llvm_unreachables.
llvm-svn: 140407
2011-09-23 20:26:49 +00:00
David Blaikie 83d382b1ca Switch assert(0/false) llvm_unreachable.
llvm-svn: 140367
2011-09-23 05:06:16 +00:00
Ted Kremenek 001fd5b498 Rename GRState to ProgramState, and cleanup some code formatting along the way.
llvm-svn: 137665
2011-08-15 22:09:50 +00:00
Ted Kremenek 5ef32dbf2a Cleanup various declarations of 'Stmt*' to be 'Stmt *', etc. in libAnalyzer and libStaticAnalyzer[*]. It was highly inconsistent, and very ugly to look at.
llvm-svn: 137537
2011-08-12 23:37:29 +00:00
Ted Kremenek 8df44b2632 [analyzer] Introduce new MemRegion, "TypedValueRegion", so that we can separate TypedRegions that implement getValueType() from those that don't.
Patch by Olaf Krzikalla!

llvm-svn: 137498
2011-08-12 20:02:48 +00:00
Ted Kremenek 73665188fc Really remove FlatStoreManager and BasicStoreManager, this time from the driver. Also remove associated tests. Sorry for the messy commits; this is the result of a botched Git merge.
llvm-svn: 136422
2011-07-28 23:08:16 +00:00
Zhanyong Wan 5ad574c096 Improves the coding style in SValBuilder. This patch:
- renames evalCastNL and evalCastL to evalCastFromNonLoc and
  evalCastFromLoc (avoid abbreviations that aren't well known).

- makes all function parameter names start with a lower case letter
  for consistency and distinction from member variables.

- avoids abbreviations in function parameter names.

Reviewed by kremenek@apple.com.

llvm-svn: 126722
2011-03-01 00:45:32 +00:00
Argyrios Kyrtzidis eb8357c1d8 [analyzer] Fix crash when analyzing C++ code.
llvm-svn: 126025
2011-02-19 08:03:18 +00:00