Commit Graph

28 Commits

Author SHA1 Message Date
Ted Kremenek 7efe43db99 Patch by Ben Laurie:
ConstraintManager:
- constify getSymVal()

BasicConstraintManager:
- Pull out logic that would be common to ConstraintManagers of a similar nature
  and put them in a parent class called 'SimpleConstraintManager'.

RangeConstraintManager:
- Added a new prototype ConstraintManager to track ranges of variables! This
  ConstraintManager keeps tracks of ranges of concrete integers that a symbolic
  integer may have.

AnalysisConsumer:
- Add driver option to use RangeConstraintManager with GRExprEngine-based
  analyses.

llvm-svn: 64558
2009-02-14 17:08:39 +00:00
Zhongxing Xu 9103df1688 Make SymbolicRegion subclass TypedRegion, for symbols usually have types, so
do the symblic regions associated with them and we need them to be typed.

Current SymbolicRegion::getRValueType() method is very restricting. It may be
modified when we are more clear about what could be the types of symblic
regions.

BasicConstraintManager::Assume() is changed due to that now SymblicRegion is a
subclass of SubRegion.
 

llvm-svn: 63844
2009-02-05 06:57:29 +00:00
Chris Lattner 34beb046ea update for change in API.
llvm-svn: 63363
2009-01-30 01:58:33 +00:00
Ted Kremenek 2e561dd491 Remove method 'AddNE' from the public interface of ConstraintManager.
llvm-svn: 63249
2009-01-28 22:27:59 +00:00
Ted Kremenek e9193283c6 Use tag classes instead of typedefs for GDM entries 'ConstNotEq' and 'ConstEq'. This avoids collisions in the GDM.
llvm-svn: 63002
2009-01-26 06:04:53 +00:00
Ted Kremenek 74040833e4 Static analyzer: Remove a bunch of outdated SymbolData objects and
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
2009-01-22 18:23:34 +00:00
Ted Kremenek 16fbfe699e 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
2009-01-21 22:26:05 +00:00
Ted Kremenek 62d4c12d2c CF-retain/release checker:
- 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
2008-12-17 21:50:35 +00:00
Ted Kremenek d8242f19f7 Rename SymbolID to SymbolRef. This is a precursor to some overhauling of the representation of symbolic values.
llvm-svn: 60575
2008-12-05 02:27:51 +00:00
Ted Kremenek fff9f4aaaf BasicConstraintManager:
- 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
2008-12-03 19:06:30 +00:00
Ted Kremenek f935cfe277 BasicConstraintManager:
- 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
2008-12-03 18:56:12 +00:00
Zhongxing Xu 59e2d41a8e Factory objects should not be temporary. It caches all objects in the set.
llvm-svn: 60151
2008-11-27 06:08:40 +00:00
Zhongxing Xu b94f440754 Add comments.
llvm-svn: 60146
2008-11-27 02:39:34 +00:00
Sebastian Redl 81c1e1306c Fix crash of array bounds checking under 64-bit.
There might be other, similar bugs lurking there.

llvm-svn: 59974
2008-11-24 19:35:33 +00:00
Zhongxing Xu 4d45b34a8a Initial support for checking out of bound memory access. Only support
ConcreteInt index for now.

llvm-svn: 59869
2008-11-22 13:21:46 +00:00
Zhongxing Xu 1c31dbe417 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
2008-11-10 05:00:06 +00:00
Zhongxing Xu 60de6c6c63 Remove loc::StringLiteralVal. Now we allocate regions for string literals in the Store.
llvm-svn: 58182
2008-10-26 02:27:21 +00:00
Ted Kremenek 1416a521b5 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
2008-10-17 21:22:20 +00:00
Zhongxing Xu 27f174214d This patch did the following renaming. There should be no functional changes.
RVal => SVal
LVal => Loc
NonLVal => NonLoc
lval => loc
nonlval => nonloc

llvm-svn: 57671
2008-10-17 05:57:07 +00:00
Ted Kremenek 3ad391d800 Remove lval::FieldOffset, lval::ArrayOffset. These will be replaced with regions.
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
2008-10-17 00:51:01 +00:00
Ted Kremenek 5ca90a244f 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
2008-10-04 05:50:14 +00:00
Ted Kremenek 34bfd8a490 Fixed logic error in BasicConstraintManager pointed out by Zhongxing Xu.
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
2008-09-19 18:00:36 +00:00
Zhongxing Xu a8e88ecda6 Add an omitted case for AssumeSymInt.
llvm-svn: 56334
2008-09-19 06:07:59 +00:00
Ted Kremenek 8782716c4a Minor pass-sensitivity improvement:
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
2008-09-16 23:24:45 +00:00
Daniel Dunbar c62cf79290 Add newline at end of file.
llvm-svn: 55559
2008-08-30 02:06:22 +00:00
Zhongxing Xu 4c23963de8 Added LLVM comment header.
llvm-svn: 55537
2008-08-29 15:09:12 +00:00
Zhongxing Xu c1bd3a5f8b Migrate the rest symbolic analysis stuff to BasicConstraintManager.
llvm-svn: 55536
2008-08-29 14:52:36 +00:00
Zhongxing Xu f71b5f39bb Refactor Assume logic into a separate class ConstraintManager.
llvm-svn: 55412
2008-08-27 14:03:33 +00:00