Static Analyzer: Replace LiveSymbols/DeadSymbols sets with a new object called "SymbolReaper".  Right now it just consolidates the two and cleans up some client code, but shortly it will be used to enable "lazy computation" of live symbols for use with RegionStore.

llvm-svn: 62722

- Fix regression reported in <rdar://problem/6452745>.  After a null check, null references to resources should not have a retain count.  This regression was caused by removing the call to "GRTransferFuncs::EvalAssume" in BasicConstraintManager.
- Added a test case to test this behavior.

llvm-svn: 61155

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

llvm-svn: 60575

- Fix nonsensical logic in AssumeSymGE. When comparing 'sym >= constant' and the
  constant is the maximum integer value, add the constraint that 'sym ==
  constant' when the path is deemed feasible.  All other cases are feasible.
- Improve AssumeSymGT. When comparing 'sym > constant' and constant is the
  maximum integer value we know the path is infeasible.
- Add test case for this enhancement to AssumeSymGT.

llvm-svn: 60490

- Fix nonsensical logic in AssumeSymLE. When comparing 'sym <= constant' and the
  constant is the minimum integer value, add the constraint that 'sym ==
  constant' when the path is deemed feasible.  All other cases are feasible.
- Improve AssumeSymLT to address <rdar://problem/6407949>.  When comparing
  'sym < constant' and constant is the minimum integer value we know the
  path is infeasible.
- Add test case for <rdar://problem/6407949>.

llvm-svn: 60489

llvm-svn: 60151

llvm-svn: 60146

There might be other, similar bugs lurking there.

llvm-svn: 59974

ConcreteInt index for now.

llvm-svn: 59869

Print integer value instead of raw pointer. This is a hack to be fixed by migrating the output in analyzer to llvm::raw_ostream.

llvm-svn: 58965

llvm-svn: 58182

Enhance "Assumption" logic in BasicConstraintManager when reasoning about regions and symbolic regions.  When assuming whether or not a location is non-null, walk up the region hierarchy until we hit a symbolic region (and test it for null).  This may not be the end all solution, as the notion of what a "symbolic region" is really belongs in the specific subclass of StoreManager.

llvm-svn: 57730

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

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

For checking if a symbol >= value, we need to check if symbol == value || symbol
> value. When checking symbol > value and we know that symbol != value, the path
is infeasible only if value == maximum integer.

For checking if a symbol <= value, we need to check if symbol == value || symbol
< value. When checking symbol < value and we know that symbol != value, the path
is infeasible only if value == minimum integer.

Updated test case exercising this logic: we only prune paths if the values are
unsigned.

llvm-svn: 56354

llvm-svn: 56334

  if we know that 'len != 0' and know that 'i == 0' then we know that
  'i < len' must evaluate to true and cannot evaluate to false

llvm-svn: 56260

llvm-svn: 55559

llvm-svn: 55537

llvm-svn: 55536

llvm-svn: 55412