The autorelease pool has not been implemented completely: we were adding
the autoreleased symbols to the state, but never looking at them. Until
we have a complete implementation, remove the overhead and comment out
the unused code.
llvm-svn: 161821
to set/get/remove the RefBinding.
No functional change here. Having these setter and getter methods will
make it much easier when replacing the underlining representation of
RefBindings (I just went through the exercise). It makes the code more
readable as well.
llvm-svn: 161820
While there is now some duplication between SimpleCall and the CXXInstanceCall
sub-hierarchy, this is much better than copy-and-pasting the devirtualization
logic shared by both instance methods and destructors.
An unfortunate side effect is that there is no longer a single CallEvent type
that corresponds to "calls written as CallExprs". For the most part this is a
good thing, but the checker callback eval::Call still takes a CallExpr rather
than a CallEvent (since we're not sure if we want to allow checkers to
evaluate other kinds of calls). A mistake here will be caught by a cast<> in
CheckerManager::runCheckersForEvalCall.
No functionality change.
llvm-svn: 161809
Virtual base regions are never layered, so simply stripping them off won't
necessarily get you to the correct casted class. Instead, what we want is
the same logic for evaluating dynamic_cast: strip off base regions if possible,
but add new base regions if necessary.
llvm-svn: 161808
This can occur with multiple inheritance, which jumps from one parent to
the other, and with virtual inheritance, since virtual base regions always
wrap the actual object and can't be nested within other base regions.
This also exposed some incorrect logic for multiple inheritance: even if B
is known not to derive from C, D might still derive from both of them.
llvm-svn: 161798
...and /do/ strip CXXBaseObjectRegions when casting to a virtual base class.
This allows us to enforce the invariant that a CXXBaseObjectRegion can always
provide an offset for its base region if its base region has a known class
type, by only allowing virtual bases and direct non-virtual bases to form
CXXBaseObjectRegions.
This does mean some slight problems for our modeling of dynamic_cast, which
needs to be resolved by finding a path from the current region to the class
we're trying to cast to.
llvm-svn: 161797
This was causing a crash when we tried to re-apply a base object region to
itself. It probably also caused incorrect offset calculations in RegionStore.
PR13569 / <rdar://problem/12076683>
llvm-svn: 161710
This mostly affects pure virtual methods, but would also affect parent
methods defined inline in the header when analyzing the child's source file.
llvm-svn: 161709
This check is also accessible through the debug.ExprInspection checker.
Like clang_analyzer_eval, you can use it to test the analyzer engine's
current state; the argument should be true or false to indicate whether or
not you expect the function to be inlined.
When used in the positive case (clang_analyzer_checkInlined(true)), the
analyzer prints the message "TRUE" if the function is ever inlined. However,
clang_analyzer_checkInlined(false) should never print a message; this asserts
that there should be no paths on which the current function is inlined, but
then there are no paths on which to print a message! (If the assertion is
violated, the message "FALSE" will be printed.)
This asymmetry comes from the fact that the only other chance to print a
message is when the function is analyzed as a top-level function. However,
when we do that, we can't be sure it isn't also inlined elsewhere (such as
in a recursive function, or if we want to analyze in both general or
specialized cases). Rather than have all checkInlined calls have an appended,
meaningless "FALSE" or "TOP-LEVEL" case, there is just no message printed.
void clang_analyzer_checkInlined(int);
For debugging purposes only!
llvm-svn: 161708
when we don't need to split.
In some cases we know that a method cannot have a different
implementation in a subclass:
- the class is declared in the main file (private)
- all the method declarations (including the ones coming from super
classes) are in the main file.
This can be improved further, but might be enough for the heuristic.
(When we are too aggressive splitting the state, efficiency suffers.
When we fail to split the state coverage might suffer.)
llvm-svn: 161681
Both methods need to clear out existing bindings and provide a new default
binding. Originally KillStruct always provided UnknownVal as the default,
but it's allowed symbolic values for quite some time (for handling returned
structs in C).
No functionality change.
llvm-svn: 161637
This should speed up activities that need to access bindings by cluster,
such as invalidation and dead-bindings cleaning. In some cases all we save
is the cost of building the region cluster map, but other times we can
actually avoid traversing the rest of the store.
In casual testing, this produced a speedup of nearly 10% analyzing SQLite,
with /less/ memory used.
llvm-svn: 161636
This makes it faster to access and invalidate bindings with symbolic offsets
by only computing this information once.
No intended functionality change.
llvm-svn: 161635
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
Remove Escaped state, which is not really necessary. We can just stop
tracking the symbol instead of keeping it around and marking escaped.
llvm-svn: 161557
This is an initial (unoptimized) version. We split the path when
inlining ObjC instance methods. On one branch we always assume that the
type information for the given memory region is precise. On the other we
assume that we don't have the exact type info. It is important to check
since the class could be subclassed and the method can be overridden. If
we always inline we can loose coverage.
Had to refactor some of the call eval functions.
llvm-svn: 161552
Unfortunately, generalized region printing is very difficult:
- ElementRegions are used both for casting and as actual elements.
- Accessing values through a pointer means going through an intermediate
SymbolRegionValue; symbolic regions are untyped.
- Referring to implicitly-defined variables like 'this' and 'self' could be
very confusing if they come from another stack frame.
We fall back to simply not printing the region name if we can't be sure it
will print well. This will allow us to improve in the future.
llvm-svn: 161512
The main blocker on this (besides the previous commit) was that
ScanReachableSymbols was not looking through LazyCompoundVals.
Once that was fixed, it's easy enough to clear out malloc data on return,
just like we do when we bind to a global region.
<rdar://problem/10872635>
llvm-svn: 161511
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
I currently have a bit of redundancy with the cast kind switch statement
inside the ImplicitCast callback, but I might be adding more casts going
forward.
llvm-svn: 161358
Instead of sprinkling dynamic type info propagation throughout
ExprEngine, the added checker would add the more precise type
information on known APIs (Ex: ObjC alloc, new) and propagate
the type info in other cases (ex: ObjC init method, casts (the second is
not implemented yet)).
Add handling of ObjC alloc, new and init to the checker.
llvm-svn: 161357
The frameworks correctly use the 'cf_consumed' and 'ns_returns_retained'
attributes for NSMakeCollectable, but we can model the behavior under
garbage collection more precisely than that.
No functionality change.
llvm-svn: 161349
While there is no such thing as a "null reference" in the C++ standard,
many implementations of references (including Clang's) do not actually
check that the location bound to them is non-null. Thus unlike a regular
null dereference, this will not cause a problem at runtime until the
reference is actually used. In order to catch these cases, we need to not
prune out paths on which the input pointer is null.
llvm-svn: 161288
Like base constructors, delegating constructors require no further
processing in the CFGInitializer node.
Also, add PrettyStackTraceLoc to the initializer and destructor logic
so we can get better stack traces in the future.
llvm-svn: 161283
Because of this, we would previously emit NO path notes when a parameter
is constrained to null (because there are no stores). Now we show where we
made the assumption, which is much more useful.
llvm-svn: 161280
The visitor walks back through the ExplodedGraph as expected, but
it wasn't actually keeping track of when a value was assigned. This
meant that it only worked when the value was assigned when the variable
was defined.
Tests in the next commit (dependent on another change).
llvm-svn: 161276
In the following code, find the type of the symbolic receiver by
following it and updating the dynamic type info in the state when we
cast the symbol from id to MyClass *.
MyClass *a = [[self alloc] init];
return 5/[a testSelf];
llvm-svn: 161264
There is no reason why we should not track the memory which was not
allocated in the current function, but was freed there. This would
allow to catch more use-after-free and double free with no/limited IPA.
Also fix a realloc issue which surfaced as the result of this patch.
llvm-svn: 161248
engine.
The code that was supposed to split the tie in a deterministic way is
not deterministic. Most likely one of the profile methods uses a
pointer. After this change we do finally get the consistent diagnostic
output. Testing this requires running the analyzer on large code bases
and diffing the results.
llvm-svn: 161224
There's still more work to be done here; this doesn't catch reference
parameters or return values. But it's a step in the right direction.
Part of <rdar://problem/11212286>.
llvm-svn: 161214
This makes the diagnostic output order deterministic.
1) This makes order of text diagnostics consistent from run to run.
2) Also resulted in different bugs being reported (from one run to
another) with plist-html output.
llvm-svn: 161151
While usually we'd use a symbolic region rather than a straight-up Unknown,
we can still generate unknowns via array subscripts with symbolic indexes.
(And if this ever changes in the future, we still shouldn't crash.)
llvm-svn: 161059
This was causing a crash in our array-to-pointer logic, since the region
was clearly not an array.
PR13440 / <rdar://problem/11977113>
llvm-svn: 161051
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
Previously, we were only checking the origin expressions of inlined calls.
Checkers using the generic postCall and older postObjCMessage callbacks were
ignored. Now that we have CallEventManager, it is much easier to create
a CallEvent generically when exiting an inlined function, which we can then
use for post-call checks.
No test case because we don't (yet) have any checkers that depend on this
behavior (which is why it hadn't been fixed before now).
llvm-svn: 161005
- 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
This ensures that it is valid to reference-count any CallEvents, and we
won't accidentally try to reclaim a CallEvent that lives on the stack.
It also hides an ugly switch statement for handling CallExprs!
There should be no functionality change here.
llvm-svn: 160986
This allows us to get around the C++ "virtual constructor" problem
when we'd like to create a CallEvent from an ExplodedNode, an inlined
StackFrameContext, or another CallEvent. The solution has three parts:
- CallEventManager uses a BumpPtrAllocator to allocate CallEvent-sized
memory blocks. It also keeps a cache of freed CallEvents for reuse.
- CallEvents all have protected copy constructors, along with cloneTo()
methods that use placement new to copy into CallEventManager-managed
memory, vtables intact.
- CallEvents owned by CallEventManager are now wrapped in an
IntrusiveRefCntPtr. Going forwards, it's probably a good idea to create
ALL CallEvents through the CallEventManager, so that we don't accidentally
try to reclaim a stack-allocated CallEvent.
All of this machinery is currently unused but will be put into use shortly.
llvm-svn: 160983
We were treating this like a CXXDefaultArgExpr, but
SubstNonTypeTemplateParmExpr actually appears when a template is
instantiated, i.e. we have all the information necessary to evaluate it.
This allows us to inline functions like llvm::array_lengthof.
<rdar://problem/11949235>
llvm-svn: 160846
It's a good thing CallEvents aren't created all over the place yet.
I checked all the uses this time and the private copy constructor
/really/ shouldn't cause any more problems.
llvm-svn: 160845
instead of walking to the preceding PostStmt node. There are cases where the last evaluated
expression does not appear in the ExplodedGraph.
Fixes PR 13466.
llvm-svn: 160819
After discussion, the type-based dispatch was decided to be bad for
maintenance and made it very easy for subtle bugs to creep in. Instead,
we'll just be very careful when we do have to allocate these on the heap.
llvm-svn: 160817
Our BugReporter knows how to deal with implicit statements: it looks in
the ParentMap until it finds a parent with a valid location. However, since
initializers are not in the body of a constructor, their sub-expressions are
not in the ParentMap. That was easy enough to fix in AnalysisDeclContext.
...and then even once THAT was fixed, there's still an extra funny case
of Objective-C object pointer fields under ARC, which are initialized with
a top-level ImplicitValueInitExpr. To catch these cases,
PathDiagnosticLocation will now fall back to the start of the current
function if it can't find any other valid SourceLocations. This isn't great,
but it's miles better than a crash.
(All of this is only relevant when constructors and destructors are being
inlined, i.e. under -cfg-add-initializers and -cfg-add-implicit-dtors.)
llvm-svn: 160810
This workaround is fairly lame: we simulate the first element's constructor
and destructor and rely on the region invalidation to "initialize" the rest
of the elements.
llvm-svn: 160809
Previously we were using ParentMap and crawling through the parent DeclStmt.
This should be at least slightly cheaper (and is also more flexible).
No (intended) functionality change.
llvm-svn: 160807
Most of the logic here is fairly simple; the interesting thing is that
we now distinguish complete constructors from base or delegate constructors.
We also make sure to cast to the base class before evaluating a constructor
or destructor, since non-virtual base classes may behave differently.
This includes some refactoring of VisitCXXConstructExpr and VisitCXXDestructor
in order to keep ExprEngine.cpp as clean as possible (leaving the details for
ExprEngineCXX.cpp).
llvm-svn: 160806
This modifies BugReporter and friends to handle CallEnter and CallExitEnd
program points that came from implicit call CFG nodes (read: destructors).
This required some extra handling for nested implicit calls. For example,
the added multiple-inheritance test case has a call graph that looks like this:
testMultipleInheritance3
~MultipleInheritance
~SmartPointer
~Subclass
~SmartPointer
***bug here***
In this case we correctly notice that we started in an inlined function
when we reach the CallEnter program point for the second ~SmartPointer.
However, when we reach the next CallEnter (for ~Subclass), we were
accidentally re-using the inner ~SmartPointer call in the diagnostics.
Rather than guess if we saw the corresponding CallExitEnd based on the
contents of the active path, we now just ask the PathDiagnostic if there's
any known stack before popping off the top path.
(A similar issue could have occured without multiple inheritance, but there
wasn't a test case for it.)
llvm-svn: 160804
- Some cleanup(the TODOs) will be done after ObjC method inlining is
complete.
- Simplified CallEvent::getDefinition not to require ISDynamicDispatch
parameter.
- Also addressed Jordan's comments from r160530.
llvm-svn: 160768
value by scanning the path, rather than assuming we have visited the '?:' operator
as a terminator (which sets a value indicating which expression to grab the
final ternary expression value from).
llvm-svn: 160760
to fix all the issues. Currently the code is essentially unmaintained and buggy, and
needs major revision (with coupled enhancements to the analyzer core).
llvm-svn: 160754
As pointed out by Anna, we only differentiate between explicit message sends
This also adds support for ObjCSubscriptExprs, which are basically the same
as properties in many ways. We were already checking these, but not emitting
nice messages for them.
This depends on the llvm::PointerIntPair change in r160456.
llvm-svn: 160461
We will need to be able to easily reconstruct a CallEvent from an ExplodedNode
for diagnostic purposes, and that's exactly what factory functions are for.
CallEvent objects are small enough (four pointers and a SourceLocation) that
returning them through the stack is fairly cheap. Clients who just need to use
existing CallEvents can continue to do so using const references.
This uses the same sort of "kind-field-dispatch" as SVal, though most of the
nastiness is contained in the DISPATCH and DISPATCH_ARG macros at the end of
the file. (We can't use a template for this because member-pointers to base
class methods don't call derived-class methods even when casting to the
derived class. We can't use variadic macros because they're a C99 feature.)
llvm-svn: 160459
ObjC properties are handled through their semantic form of ObjCMessageExprs
and their wrapper PseudoObjectExprs, and have been for quite a while. The
syntactic ObjCPropertyRefExprs do not appear in the CFG and are not visited
by ExprEngine.
No functionality change.
llvm-svn: 160458
This enables the faster SmallVector in clang and also allows clang's unused
variable warnings to be more effective. Fix the two instances that popped up.
The RetainCountChecker change actually changes functionality, it would be nice
if someone from the StaticAnalyzer folks could look at it.
llvm-svn: 160444
This code has been moved around multiple times, but seems to have been
obsolete ever since we started handled references like pointers.
llvm-svn: 160375
instead push the terminator for the branch down into the basic blocks of the subexpressions of '&&' and '||'
respectively. This eliminates some artifical control-flow from the CFG and results in a more
compact CFG.
Note that this patch only alters the branches 'while', 'if' and 'for'. This was complex enough for
one patch. The remaining branches (e.g., do...while) can be handled in a separate patch, but they
weren't immediately tackled because they were less important.
It is possible that this patch introduces some subtle bugs, particularly w.r.t. to destructor placement.
I've tried to audit these changes, but it is also known that the destructor logic needs some refinement
in the area of '||' and '&&' regardless (i.e., their are known bugs).
llvm-svn: 160218
Anna Zaks