Commit Graph

51 Commits

Author SHA1 Message Date
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
Ted Kremenek a85f38ba3a Rework ExprEngine::evalLoad and clients (e.g. VisitBinaryOperator) so that when we generate a new ExplodedNode
we use the same Expr* as the one being currently visited.  This is preparation for transitioning to having
ProgramPoints refer to CFGStmts.

This required a bit of trickery.  We wish to keep the old Expr* bindings in the Environment intact,
as plenty of logic relies on it and there is no reason to change it, but we sometimes want the Stmt* for
the ProgramPoint to be different than the Expr* being used for bindings.  This requires adding an extra
argument for some functions (e.g., evalLocation).  This looks a bit strange for some clients, but
it will look a lot cleaner when were start using CFGStmt* in the appropriate places.

As some fallout, the diagnostics arrows are a bit difference, since some of the node locations have changed.
I have audited these, and they look reasonable.

llvm-svn: 154214
2012-04-06 22:10:18 +00:00
Ted Kremenek 34ac1cf3cd Handle symbolicating a reference in an initializer expression that we don't understand.
llvm-svn: 154084
2012-04-05 05:56:31 +00:00
David Blaikie bbafb8a745 Unify naming of LangOptions variable/get function across the Clang stack (Lex to AST).
The member variable is always "LangOpts" and the member function is always "getLangOpts".

Reviewed by Chris Lattner

llvm-svn: 152536
2012-03-11 07:00:24 +00:00
Douglas Gregor ed90df3800 Generate an AST for the conversion from a lambda closure type to a
block pointer that returns a block literal which captures (by copy)
the lambda closure itself. Some aspects of the block literal are left
unspecified, namely the capture variable (which doesn't actually
exist) and the body (which will be filled in by IRgen because it can't
be written as an AST).

Because we're switching to this model, this patch also eliminates
tracking the copy-initialization expression for the block capture of
the conversion function, since that information is now embedded in the
synthesized block literal. -1 side tables FTW.

llvm-svn: 151131
2012-02-22 05:02:47 +00:00
Ted Kremenek d519cae8aa Have conjured symbols depend on LocationContext, to add context sensitivity for functions called more than once.
llvm-svn: 150849
2012-02-17 23:13:45 +00:00
John McCall c62bb39142 Split reinterpret_casts of member pointers out from CK_BitCast; this
is general goodness because representations of member pointers are
not always equivalent across member pointer types on all ABIs
(even though this isn't really standard-endorsed).

Take advantage of the new information to teach IR-generation how
to do these reinterprets in constant initializers.  Make sure this
works when intermingled with hierarchy conversions (although
this is not part of our motivating use case).  Doing this in the
constant-evaluator would probably have been better, but that would
require a *lot* of extra structure in the representation of
constant member pointers:  you'd really have to track an arbitrary
chain of hierarchy conversions and reinterpretations in order to
get this right.  Ultimately, this seems less complex.  I also
wasn't quite sure how to extend the constant evaluator to handle
foldings that we don't actually want to treat as extended
constant expressions.

llvm-svn: 150551
2012-02-15 01:22:51 +00:00
Ted Kremenek 76978f9d6c Remove recusive expression visitation in ExprEngine::VisitIncrementDecrementOperator().
llvm-svn: 150511
2012-02-14 21:38:30 +00:00
Ted Kremenek 89dbd3ba40 Remove recursive visitation in ExprEngine for UO_Not, UO_Minus, UO_LNot.
llvm-svn: 150509
2012-02-14 21:31:00 +00:00
Ted Kremenek 8c8578c0b8 Remove recursive visitation in ExprEngine for UO_Deref, UO_AddrOf, and UO_Extension.
llvm-svn: 150506
2012-02-14 21:27:05 +00:00
Ted Kremenek c14557fb6a Remove ExprEngine recursive visitation of unary UO_Imag operation.
llvm-svn: 150505
2012-02-14 21:27:02 +00:00
Ted Kremenek b5d87d8843 Further remove some recursive visitiation in ExprEngine that is no longer needed because the CFG is fully linearized.
llvm-svn: 150504
2012-02-14 21:26:59 +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
David Chisnall fa35df628a Some improvements to the handling of C11 atomic types:
- Add atomic-to/from-nonatomic cast types
- Emit atomic operations for arithmetic on atomic types
- Emit non-atomic stores for initialisation of atomic types, but atomic stores and loads for every other store / load
- Add a __atomic_init() intrinsic which does a non-atomic store to an _Atomic() type.  This is needed for the corresponding C11 stdatomic.h function.
- Enables the relevant __has_feature() checks.  The feature isn't 100% complete yet, but it's done enough that we want people testing it.

Still to do:

- Make the arithmetic operations on atomic types (e.g. Atomic(int) foo = 1; foo++;) use the correct LLVM intrinsic if one exists, not a loop with a cmpxchg.
- Add a signal fence builtin
- Properly set the fenv state in atomic operations on floating point values
- Correctly handle things like _Atomic(_Complex double) which are too large for an atomic cmpxchg on some platforms (this requires working out what 'correctly' means in this context)
- Fix the many remaining corner cases

llvm-svn: 148242
2012-01-16 17:27:18 +00:00
Ted Kremenek 632e3b7ee2 [analyzer] Make the entries in 'Environment' context-sensitive by making entries map from
(Stmt*,LocationContext*) pairs to SVals instead of Stmt* to SVals.

This is needed to support basic IPA via inlining.  Without this, we cannot tell
if a Stmt* binding is part of the current analysis scope (StackFrameContext) or
part of a parent context.

This change introduces an uglification of the use of getSVal(), and thus takes
two steps forward and one step back.  There are also potential performance implications
of enlarging the Environment.  Both can be addressed going forward by refactoring the
APIs and optimizing the internal representation of Environment.  This patch
mainly introduces the functionality upon when we want to build upon (and clean up).

llvm-svn: 147688
2012-01-06 22:09:28 +00:00
Richard Smith 5fab0c9e1a Small refactoring and simplification of constant evaluation and some of its
clients. No functionality change.

llvm-svn: 147318
2011-12-28 19:48:30 +00:00
Anna Zaks 2d2999821b [analyzer] Simplify the condition.
This is a fixup for r145832.

The extra clauses do not matter after we remove the dependency on canReasonAbout(InitVal) in r145832.

llvm-svn: 145856
2011-12-05 21:33:01 +00:00
Anna Zaks a636fbe73f [analyzer] Remove all uses of ConstraintManager::canResonAbout() from
ExprEngine.

Teach SimpleConstraintManager::assumeSymRel() to propagate constraints
to symbolic expressions.

+ One extra warning (real bug) is now generated due to enhanced
assumeSymRel().

llvm-svn: 145832
2011-12-05 18:58:25 +00:00
Anna Zaks 51090d5f7f [analyzer] First step toward removing
ConstraintManager::canReasonAbout() from the ExprEngine.

ExprEngine should not care if the constraint solver can reason about
something or not. The solver should be able to handle all the SymExprs.

To do this, the solver should be able to keep track of not only the
SymbolData but of all SymExprs. This is why we change SymbolRef to be an
alias of SymExpr*. When encountering an expression it cannot simplify,
the solver should just add the constraints to it.

llvm-svn: 145831
2011-12-05 18:58:19 +00:00
Anna Zaks 040ddfedc0 [analyzer] Do not conjure a symbol when we need to propagate taint.
When the solver and SValBuilder cannot reason about symbolic expressions (ex: (x+1)*y ), the analyzer conjures a new symbol with no ties to the past. This helps it to recover some path-sensitivity. However, this breaks the taint propagation.

With this commit, we are going to construct the expression even if we cannot reason about it later on if an operand is tainted.

Also added some comments and asserts.

llvm-svn: 144932
2011-11-17 23:07:28 +00:00
John McCall ffc8ca2d84 Rip out CK_GetObjCProperty.
llvm-svn: 143910
2011-11-07 05:09:54 +00:00
Benjamin Kramer 62144477eb Remove unused variables.
llvm-svn: 143696
2011-11-04 15:05:51 +00:00
Anna Zaks bfb3520fc5 [analyzer] Make sure the child builder use temporary destination sets
The parent and child builders should not share node sets.

llvm-svn: 143515
2011-11-01 22:41:09 +00:00
Richard Smith 7b553f1b19 Rename Expr::Evaluate to Expr::EvaluateAsRValue to make it clear that it will
implicitly perform an lvalue-to-rvalue conversion if used on an lvalue
expression. Also improve the documentation of Expr::Evaluate* to indicate which
of them will accept expressions with side-effects.

llvm-svn: 143263
2011-10-29 00:50:52 +00:00
Anna Zaks 513921dc8a [analyzer] Remove unused headers.
llvm-svn: 142945
2011-10-25 19:56:58 +00:00
Anna Zaks e4e5712cd7 [analyzer] Node builders cleanup + comments
Renamed PureNodeBuilder->StmtNodeBuilder.

llvm-svn: 142849
2011-10-24 21:19:59 +00:00
Anna Zaks 4c9169254f [analyzer] Completely remove the global Builder object.
llvm-svn: 142847
2011-10-24 21:19:48 +00:00
Anna Zaks e594034f1f [analyzer] Convert ExprEngine::visit() to use short lived builders.
This commit removes the major functional dependency on the ExprEngine::Builder
member variable.

In some cases the code became more verbose. Particularly, we call takeNodes()
and addNodes() to move responsibility for the nodes from one builder to another.
This will get simplified later on.

llvm-svn: 142831
2011-10-24 18:26:19 +00:00
Anna Zaks 5236792019 [analyzer] Convert VisitDeclStmt to use local node builder.
llvm-svn: 142830
2011-10-24 18:26:12 +00:00
Anna Zaks cbdf10be19 [analyzer] Convert more functions (ex:evalBind()) to iterative builders
llvm-svn: 142829
2011-10-24 18:26:08 +00:00
Anna Zaks f011a4a6f9 [analyzer] Convert VisitUnaryOperator to use short lived Node builders
To convert iteratively, we take the nodes the local builder will
process from the from the global builder and add the generated nodes
after the short lived builder is done. PureStmtNodeBuilder is the
one we should eventually use everywhere. Added Stmt index and Builder
context as ExprEngine globals. To avoid passing them around.

llvm-svn: 142828
2011-10-24 18:26:03 +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
John McCall 2d637d2e79 Rename the ARC cast kinds to start with "ARC".
llvm-svn: 139466
2011-09-10 06:18:15 +00:00
John McCall cd78e805e9 When converting a block pointer to an Objective-C pointer type, extend
the lifetime of the block by copying it to the heap, or else we'll get
a dangling reference because the code working with the non-block-typed
object will not know it needs to copy.

There is some danger here, e.g. with assigning a block literal to an
unsafe variable, but, well, it's an unsafe variable.

llvm-svn: 139451
2011-09-10 01:16:55 +00:00
John McCall 9320b87cff Give conversions of block pointers to ObjC pointers a different cast kind
than conversions of C pointers to ObjC pointers.  In order to ensure that
we've caught every case, add asserts to CastExpr that strictly determine
which cast kind is used for which kind of bit cast.

llvm-svn: 139352
2011-09-09 05:25:32 +00:00
Jordy Rose e9ff97b850 [analyzer] Remove the ProgramState argument from ExprEngine::evalBind; we were ignoring it anyway. No functionality change.
llvm-svn: 138720
2011-08-28 06:02:28 +00:00
Ted Kremenek ee9848e20d Fix regression in -Wuninitialized involving VLAs. It turns out that we were modeling sizeof(VLAs)
incorrectly in the CFG, and also the static analyzer.  This patch regresses the analyzer a bit, but
that needs to be followed up with a better solution.

Fixes <rdar://problem/10008112>.

llvm-svn: 138372
2011-08-23 20:30:50 +00:00
Ted Kremenek 876e34b7b5 [analyzer] Simplify ExprEngine::VisitBinaryOperator() by removing recursive visit to subexpressions (which is no longer needed).
llvm-svn: 138195
2011-08-20 06:16:31 +00:00