Commit Graph

89 Commits

Author SHA1 Message Date
Anna Zaks 8591aa78db [analyzer] Do not crash when processing binary "?:" in C++
When computing the value of ?: expression, we rely on the last expression in
the previous basic block to be the resulting value of the expression. This is
not the case for binary "?:" operator (GNU extension) in C++. As the last
basic block has the expression for the condition subexpression, which is an
R-value, whereas the true subexpression is the L-value.

Note the operator evaluation just happens to work in C since the true
subexpression is an R-value (like the condition subexpression). CFG is the
same in C and C++ case, but the AST nodes are different, which the LValue to
Rvalue conversion happening after the BinaryConditionalOperator evaluation.

Changed the logic to only use the last expression from the predecessor only
if it matches either true or false subexpression. Note, the logic needed
fortification anyway: L and R were passed but not even used by the function.

Also, change the conjureSymbolVal to correctly compute the type, when the
expression is an LG-value.

llvm-svn: 179574
2013-04-15 22:38:07 +00:00
Jordan Rose 61e221f68d [analyzer] Replace isIntegerType() with isIntegerOrEnumerationType().
Previously, the analyzer used isIntegerType() everywhere, which uses the C
definition of "integer". The C++ predicate with the same behavior is
isIntegerOrUnscopedEnumerationType().

However, the analyzer is /really/ using this to ask if it's some sort of
"integrally representable" type, i.e. it should include C++11 scoped
enumerations as well. hasIntegerRepresentation() sounds like the right
predicate, but that includes vectors, which the analyzer represents by its
elements.

This commit audits all uses of isIntegerType() and replaces them with the
general isIntegerOrEnumerationType(), except in some specific cases where
it makes sense to exclude scoped enumerations, or any enumerations. These
cases now use isIntegerOrUnscopedEnumerationType() and getAs<BuiltinType>()
plus BuiltinType::isInteger().

isIntegerType() is hereby banned in the analyzer - lib/StaticAnalysis and
include/clang/StaticAnalysis. :-)

Fixes real assertion failures. PR15703 / <rdar://problem/12350701>

llvm-svn: 179081
2013-04-09 02:30:33 +00:00
Ted Kremenek 338c3aa8d1 Add static analyzer support for conditionally executing static initializers.
llvm-svn: 178318
2013-03-29 00:09:28 +00:00
Jordan Rose d03d99da16 Silence a number of static analyzer warnings with assertions and such.
No functionality change.

llvm-svn: 176469
2013-03-05 01:27:54 +00:00
David Blaikie 00be69ab5c Remove the CFGElement "Invalid" state.
Use Optional<CFG*> where invalid states were needed previously. In the one case
where that's not possible (beginAutomaticObjDtorsInsert) just use a dummy
CFGAutomaticObjDtor.

Thanks for the help from Jordan Rose & discussion/feedback from Ted Kremenek
and Doug Gregor.

Post commit code review feedback on r175796 by Ted Kremenek.

llvm-svn: 175938
2013-02-23 00:29:34 +00:00
Ted Kremenek a3bb2b6044 Fix regression in modeling assignments of an address of a variable to itself. Fixes <rdar://problem/13226577>.
llvm-svn: 175852
2013-02-22 01:39:26 +00:00
David Blaikie 87396b9b08 Replace ProgramPoint llvm::cast support to be well-defined.
See r175462 for another example/more details.

llvm-svn: 175812
2013-02-21 22:23:56 +00:00
David Blaikie 2a01f5d426 Replace CFGElement llvm::cast support to be well-defined.
See r175462 for another example/more details.

llvm-svn: 175796
2013-02-21 20:58:29 +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
Anna Zaks 907e126be2 [analyzer] Remove redundant check as per Jordan's feedback.
llvm-svn: 174680
2013-02-07 23:29:22 +00:00
Anna Zaks 7c1f408636 [analyzer] Don't reinitialize static globals more than once along a path
This patch makes sure that we do not reinitialize static globals when
the function is called more than once along a path. The motivation is
code with initialization patterns that rely on 2 static variables, where
one of them has an initializer while the other does not. Currently, we
reset the static variables with initializers on every visit to the
function along a path.

llvm-svn: 174676
2013-02-07 23:05:37 +00:00
Guy Benyei 1b4fb3e08b Implement OpenCL event_t as Clang builtin type, including event_t related OpenCL restrictions (OpenCL 1.2 spec 6.9)
llvm-svn: 172973
2013-01-20 12:31:11 +00:00
Ted Kremenek 4e9a2dbde5 Refine analyzer's handling of unary '!' and floating types to not assert.
Fixes PR 14634 and <rdar://problem/12903080>.

llvm-svn: 172274
2013-01-11 23:36:25 +00:00
Ted Kremenek 039fac0347 Correctly propagate uninitialized values within logical expressions.
Fixes assertion failure reported in PR 14635 and
<rdar://problem/12902945> respectively.

llvm-svn: 172263
2013-01-11 22:35:39 +00:00
Benjamin Kramer d7d2b1fe45 Don't include Type.h in DeclarationName.h.
Recursively prune some includes.

llvm-svn: 169094
2012-12-01 16:35:25 +00:00
Ted Kremenek 18035d7125 Fix another false positive due to a CXX temporary object appearing in a C initializer.
The stop-gap here is to just drop such objects when processing the InitListExpr.
We still need a better solution.

Fixes <rdar://problem/12755044>.

llvm-svn: 168757
2012-11-28 01:49:01 +00:00
Anna Zaks e5cb4981d0 [analyzer] Fix a crash PR13762.
llvm-svn: 163262
2012-09-05 22:31:58 +00:00
Jordan Rose a44ad1b35c [analyzer] Don't attempt to create a floating-point value of "1" for ++/--.
The current logic would actually create a float- or double-sized signed
integer value of 1, which is not at all the same.

No test because the value would be swallowed by an Unknown as soon as it
gets added or subtracted to the original value, but it enables the cleanup
in the next patch.

llvm-svn: 163068
2012-09-01 17:39:17 +00:00
Eli Friedman 34866c7719 Change the representation of builtin functions in the AST
(__builtin_* etc.) so that it isn't possible to take their address.
Specifically, introduce a new type to represent a reference to a builtin
function, and a new cast kind to convert it to a function pointer in the
operand of a call.  Fixes PR13195.

llvm-svn: 162962
2012-08-31 00:14:07 +00:00
Jordan Rose c93183042f [analyzer] Inline constructors for any object with a trivial destructor.
This allows us to better reason about status objects, like Clang's own
llvm::Optional (when its contents are trivially destructible), which are
often intended to be passed around by value.

We still don't inline constructors for temporaries in the general case.

<rdar://problem/11986434>

llvm-svn: 162681
2012-08-27 17:50:07 +00:00
Jordan Rose 434f132060 [analyzer] For now, treat pointers-to-members as non-null void * symbols.
Until we have full support for pointers-to-members, we can at least
approximate some of their use by tracking null and non-null values.
We thus treat &A::m_ptr as a non-null void * symbol, and MemberPointer(0)
as a pointer-sized null constant.

This enables support for what is sometimes called the "safe bool" idiom,
demonstrated in the test case.

llvm-svn: 162495
2012-08-23 23:01:43 +00:00
Jordan Rose 081af085eb [analyzer] Handle UserDefinedConversion casts in C++.
This is trivial; the UserDefinedConversion always wraps a CXXMemberCallExpr
for the appropriate conversion function, so it's just a matter of
propagating that value to the CastExpr itself.

llvm-svn: 162494
2012-08-23 23:01:39 +00:00
Ted Kremenek d94854a42e Rename 'currentX' to 'currX' throughout analyzer and libAnalysis.
Also rename 'getCurrentBlockCounter()' to 'blockCount()'.

This ripples a bunch of code simplifications; mostly aesthetic,
but makes the code a bit tighter.

llvm-svn: 162349
2012-08-22 06:26:15 +00:00
Ted Kremenek d227833cba Rename 'getConjuredSymbol*' to 'conjureSymbol*'.
No need to have the "get", the word "conjure" is a verb too!
Getting a conjured symbol is the same as conjuring one up.

This shortening is largely cosmetic, but just this simple changed
cleaned up a handful of lines, making them less verbose.

llvm-svn: 162348
2012-08-22 06:26:06 +00:00
Ted Kremenek 1afcb7442f Remove Store::bindDecl() and Store::bindDeclWithNoInit(), and
all forwarding methods.

This functionality is already covered by bindLoc().

llvm-svn: 162346
2012-08-22 06:00:18 +00:00
Jordan Rose 4b4613cbec [analyzer] Replace boolean IsSink parameters with 'generateSink' methods.
Generating a sink is significantly different behavior from generating a
normal node, and a simple boolean parameter can be rather opaque. Per
offline discussion with Anna, adding new generation methods is the
clearest way to communicate intent.

No functionality change.

llvm-svn: 162215
2012-08-20 18:43:42 +00:00
Jordan Rose 0a9ea7c70d [analyzer] The result of && or || is always a 1 or 0.
Forgetting to at least cast the result was giving us Loc/NonLoc problems
in SValBuilder (hitting an assertion). But the standard (both C and C++)
does actually guarantee that && and || will result in the actual values
1 and 0, typed as 'int' in C and 'bool' in C++, and we can easily model that.

PR13461

llvm-svn: 162209
2012-08-20 17:04:45 +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
Anna Zaks 472dbcf156 [analyzer] Add a checker to manage dynamic type propagation.
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
2012-08-06 23:25:39 +00:00
Anna Zaks 150843b87e [analyzer] ObjC Inlining: Start tracking dynamic type info in the GDM
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
2012-08-03 21:43:37 +00:00
Ted Kremenek 313c2ff375 Look at the preceding CFGBlock for the expression to load from in ExprEngine::VisitGuardedExpr
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
2012-07-26 22:23:41 +00:00
Jordan Rose 20edae8749 [analyzer] Don't crash on array constructors and destructors.
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
2012-07-26 20:04:25 +00:00
Ted Kremenek bb81ffb342 Update ExprEngine's handling of ternary operators to find the ternary expression
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
2012-07-25 21:58:25 +00:00
Jordan Rose 5089f3b398 [analyzer] Handle new-expressions with initializers for scalars.
<rdar://problem/11818967>

llvm-svn: 160328
2012-07-16 23:38:09 +00:00
Daniel Jasper 6b5a4fcc07 Prevent unused-variable warning in optimized builds.
llvm-svn: 160257
2012-07-16 10:25:15 +00:00
Ted Kremenek b50e716bac Refine CFG so that '&&' and '||' don't lead to extra confluence points when used in a branch, but
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
2012-07-14 05:04:10 +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 832c2134a9 [analyzer] Add a comment: why we treat array compound literals as lvalues.
llvm-svn: 158681
2012-06-18 21:31:27 +00:00
Jordan Rose b4712d142a [analyzer] Array CompoundLiteralExprs need to be treated like lvalues.
llvm-svn: 158588
2012-06-16 01:28:03 +00:00
Jordan Rose 2fdc07ee89 Revert "[analyzer] Treat LValueBitCasts like regular pointer bit casts."
This does not actually give us the right behavior for reinterpret_cast
of references. Reverting so I can think about it some more.

This reverts commit 50a75a6e26a49011150067adac556ef978639fe6.

llvm-svn: 158341
2012-06-12 00:20:22 +00:00
Jordan Rose ca00b28a47 [analyzer] Treat LValueBitCasts like regular pointer bit casts.
These casts only appear in very well-defined circumstances, in which the
target of a reinterpret_cast or a function formal parameter is an lvalue
reference. According to the C++ standard, the following are equivalent:

 reinterpret_cast<T&>( x)
*reinterpret_cast<T*>(&x)

[expr.reinterpret.cast]p11

llvm-svn: 158338
2012-06-11 23:20:52 +00:00
Anna Zaks 6a65819ba3 [analyzer] Don't crash on LValBitCast
llvm-svn: 157478
2012-05-25 16:02:16 +00:00
Anna Zaks fc1d4bdc4f [analyzer] Bind UnknownVal to InitListExpr for unsupported types
(ex: float).

llvm-svn: 157211
2012-05-21 22:07:00 +00:00
Anna Zaks 94a7b849a2 [analyzer] For locations, use isGLValue() instead of isLValue().
llvm-svn: 157088
2012-05-19 00:22:07 +00:00
Ted Kremenek fd727748bd Explicitly model capturing variables for blocks in the static analyzer. Fixes <rdar://problem/11125868>.
llvm-svn: 156211
2012-05-04 21:48:42 +00:00
Anna Zaks 1655aee1e3 [analyzer] Conjure a symbol to ensure we can identify pointer arithmetic
We need to identify the value of ptr as
ElementRegion (result of pointer arithmetic) in the following code.
However, before this commit '(2-x)' evaluated to Unknown value, and as
the result, 'p + (2-x)' evaluated to Unknown value as well.

int *p = malloc(sizeof(int));
ptr = p + (2-x);

llvm-svn: 156052
2012-05-03 02:13:56 +00:00
Anna Zaks f36a6f54ae [analyzer] dynamic_cast Simplify null value generation.
As per Jordy's review. Creating a symbol here is more flexible; however
I could not come up with an example where it was needed. (What
constrains can be added on of the symbol constrained to 0?)

llvm-svn: 154542
2012-04-11 22:20:07 +00:00
Anna Zaks 02ecae9282 [analyzer] dynamic_cast: Better model cast from a reference.
Generate a sink when the dynamic_cast from a reference fails to
represent a thrown exception.

llvm-svn: 154438
2012-04-10 21:29:03 +00:00
Anna Zaks 3bc6809ecb [analyzer] Add support for C++ dynamic_cast.
Simulate the C++ dynamic_cast in the analyzer.

llvm-svn: 154434
2012-04-10 20:59:00 +00:00