representing symbolic expressions like 'x'+3 and 'x'+'y'. The design is
subjected to change later when we fix the class hierarchy of symbolic
expressions.

llvm-svn: 67678

- Conjure symbols at '--' and '++' unary operations
- Add utility method SVal::GetConjuredSymbolVal() and constify some arguments
  along the way.

llvm-svn: 67395

SVal::GetRValueSymbolVal do the checking if we can symbolicate a type instead of
having BasicStoreManager do it (which wasn't always doing the check
consistently). Having this check in SVal::GetRValueSymbolVal keeps the check in
one centralized place.

llvm-svn: 67245

llvm-svn: 66555

SVal::getAsLocSymbol(). This simplifies the code and allows the retain/release
checker to (I believe) also correctly reason about location symbols wrapped in
SymbolicRegions.

Along the way I cleaned up SymbolRef a little, disallowing implicit casts to
'unsigned'.

llvm-svn: 65972

llvm-svn: 65956

- NonLoc::MakeVal() would use sizeof(unsigned) (literally) instead of consulting
  ASTContext for the size (in bits) of 'int'. While it worked, it was a
  conflation of concepts and using ASTContext.IntTy is 100% correct.
- RegionStore::getSizeInElements() no longer assumes that a VarRegion has the
  type "ConstantArray", and handles the case when uses use ordinary variables
  as if they were arrays.
- Fixed ElementRegion::getRValueType() to just return the rvalue type of its
  "array region" in the case the array didn't have ArrayType.
- All of this fixes <rdar://problem/6541136>

llvm-svn: 63347

their associated APIs.  We no longer need separate SymbolData objects
for fields, variables, etc.  Instead, we now associated symbols with
the "rvalue" of a MemRegion (i.e., the value stored at that region).
Now we only have two kinds of SymbolData objects: SymbolRegionRValue
and SymbolConjured.

This cleanup also makes the distinction between a SymbolicRegion and a
symbolic value that is a location much clearer.  A SymbolicRegion
represents a chunk of symbolic memory, while a symbolic location is
just a "pointer" with different possible values.  Without any specific
knowledge, a symbolic location resolves (i.e., via a dereference) to a
SymbolicRegion.  In the future, when we do better alias reasoning, a
symbolic location can become an alias for another location, thus
merging the constraints on the referred SymbolicRegion with the other
region.

llvm-svn: 62769

* Now Bind() methods take and return GRState* because binding could
  also alter GDM.
* No variables are initialized except those declared with initial
  values.
* failed C test cases are due to bugs in RemoveDeadBindings(),
which removes constraints that is still alive. This will be fixed in later
patch.
* default value of array and struct regions will be implemented in later patch.

llvm-svn: 61274

llvm-svn: 60758

Rename SymbolID to SymbolRef.  This is a precursor to some overhauling of the representation of symbolic values.

llvm-svn: 60575

llvm-svn: 59956

llvm-svn: 59930

ConcreteInt index for now.

llvm-svn: 59869

llvm-svn: 59618

llvm-svn: 59334

Pretty-printing for SVals now mainly uses llvm::raw_ostream.  We have an adapter for std::ostream, but this will be removed in the future.

llvm-svn: 58445

Added pretty-printing for nonloc::CompoundSVal.

llvm-svn: 58442

llvm-svn: 58441

CompoundVal now uses an ImmutableList<SVal> to store its set of SVals.  This change was motivated by the need to allow state-splitting in GRExprEngine::VisitInitListExpr.  As a side-benefit, we no longer need to perform any copies of SVals when creating a CompoundSVal, and the profiling of CompoundSVal is now constant time.

llvm-svn: 58437

llvm-svn: 58418

- Add symbol_iterator support for SymbolicRegions.

llvm-svn: 58300

llvm-svn: 58182

llvm-svn: 58073

  RValues.h/cpp => SVals.h/cpp

llvm-svn: 57893

RVal => SVal
LVal => Loc
NonLVal => NonLoc
lval => loc
nonlval => nonloc

llvm-svn: 57671

Remove GRExprEngine::getLVal and RValues::MakeVal.
Enhance StoreManager "GetLValue" methods to dispatch for specific kinds of lvalue queries, as opposed to interogating the expression tree (GRExprEngine already does this).

Added FIXMEs.  In particular, we no longer "assume" that a base pointer in a field/array access is null (this logic was removed).  Perhaps we should do this when fetching the lvalue for fields and array elements?

llvm-svn: 57657

new VisitLValue method is added to replace the old VisitLVal. The semantics
model becomes more explicit to separate rvalue evaluation from lvalue
evaluation.  

llvm-svn: 57627

This is a big patch, but the functionality change is small and the rest of the patch consists of deltas due to API changes.

This patch overhauls the "memory region" abstraction that was prototyped (but never really used) as part of the Store.h.  This patch adds MemRegion.h and MemRegion.cpp, which defines the class MemRegion and its subclasses.  This classes serve to define an abstract representation of memory, with regions being layered on other regions to to capture the relationships between fields and variables, variables and the address space they are allocated in, and so on.  

The main motivation of this patch is that key parts of the analyzer assumed that all value bindings were to VarDecls.  In the future this won't be the case, and this patch removes lval::DeclVal and replaces it with lval::MemRegionVal.  Now all pieces of the analyzer must reason about abstract memory blocks instead of just variables.

There should be no functionality change from this patch, but it opens the door for significant improvements to the analyzer such as field-sensitivity and object-sensitivity, both which were on hold until the memory abstraction got generalized.

The memory region abstraction also allows type-information to literally be affixed to a memory region.  This will allow the some now redundant logic to be removed from the retain/release checker.

llvm-svn: 57042

llvm-svn: 56912

an APInt directly to an ostream now, so add some hacks.  It would
be better to switch all of the bugreport (and friends) stuff over
to raw_ostream.

llvm-svn: 55264

llvm-svn: 54874

 - Drop {Decl.h,DeclObjC.h,IdentifierTable.h} from Expr.h
 - Moved Sema::getCurMethodDecl() out of line (dependent on
   ObjCMethodDecl via dyn_cast).

llvm-svn: 54629

llvm-svn: 53754

llvm-svn: 53753

llvm-svn: 50503

llvm-svn: 50453

This removes the failure in null-deref-ps.c (test suite).

llvm-svn: 50449

llvm-svn: 50109

Added "nonlval::LValAsInteger" to represent abstract LVals casted to integers, allowing us to track lvals when they are casted back to pointers.

llvm-svn: 50108