Commit Graph

43 Commits

Author SHA1 Message Date
Jordan Rose e3fd708f9c [analyzer] Refactor RegionStore's sub-region bindings traversal.
This is going to be used in the next commit.
While I'm here, tighten up assumptions about symbolic offset
BindingKeys, and make offset calculation explicitly handle all
MemRegion kinds.

No functionality change.

llvm-svn: 175228
2013-02-15 00:32:03 +00:00
Ted Kremenek 8ae67871b4 Change subexpressions to be visited in the CFG from left-to-right.
This is a more natural order of evaluation, and it is very important
for visualization in the static analyzer.  Within Xcode, the arrows
will not jump from right to left, which looks very visually jarring.
It also provides a more natural location for dataflow-based diagnostics.

Along the way, we found a case in the analyzer diagnostics where we
needed to indicate that a variable was "captured" by a block.

-fsyntax-only timings on sqlite3.c show no visible performance change,
although this is just one test case.

Fixes <rdar://problem/13016513>

llvm-svn: 174447
2013-02-05 22:00:19 +00:00
Ted Kremenek ff989016c1 Pull logic to map from VarDecl* to captured region using a helper function. WIP.
llvm-svn: 169479
2012-12-06 07:17:13 +00:00
Chandler Carruth 3a02247dc9 Sort all of Clang's files under 'lib', and fix up the broken headers
uncovered.

This required manually correcting all of the incorrect main-module
headers I could find, and running the new llvm/utils/sort_includes.py
script over the files.

I also manually added quite a few missing headers that were uncovered by
shuffling the order or moving headers up to be main-module-headers.

llvm-svn: 169237
2012-12-04 09:13:33 +00:00
Benjamin Kramer ea70eb30a0 Pull the Attr iteration parts out of Attr.h, so including DeclBase.h doesn't pull in all the generated Attr code.
Required to pull some functions out of line, but this shouldn't have a perf impact.
No functionality change.

llvm-svn: 169092
2012-12-01 15:09:41 +00:00
Anna Zaks e3beeaa5e7 [analyzer] Fix a crash reported in PR 14400.
The AllocaRegion did not have the superRegion (based on LocationContext)
as part of it's hash. As a consequence, the AllocaRegions from
different frames were uniqued to be the same region.

llvm-svn: 168599
2012-11-26 19:11:46 +00:00
Jordan Rose e15fb77df8 Reapply "[analyzer] Treat fields of unions as having symbolic offsets."
This time, actually uncomment the code that's supposed to fix the problem.

This reverts r165671 / 8ceb837585ed973dc36fba8dfc57ef60fc8f2735.

llvm-svn: 165676
2012-10-10 23:23:21 +00:00
Eric Christopher a529f8c9c2 Temporarily Revert "[analyzer] Treat fields of unions as having symbolic offsets."
Author: Jordan Rose <jordan_rose@apple.com>
Date:   Wed Oct 10 21:31:21 2012 +0000

    [analyzer] Treat fields of unions as having symbolic offsets.

    This allows only one field to be active at a time in RegionStore.
    This isn't quite the correct behavior for unions, but it at least
    would handle the case of "value goes in, value comes out" from the
    same field.

    RegionStore currently has a number of places where any access to a union
    results in UnknownVal being returned. However, it is clearly missing
    some cases, or the original issue wouldn't have occurred. It is probably
    now safe to remove those changes, but that's a potentially destabilizing
    change that should wait for more thorough testing.

    Fixes PR14054.

    git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@165660 91177308-0d34-0410-b5e6-96231b3b80d8

This reverts commit cf9030e480f77ab349672f00ad302e216c26c92c.

llvm-svn: 165671
2012-10-10 22:49:05 +00:00
Jordan Rose fb29410c85 [analyzer] Treat fields of unions as having symbolic offsets.
This allows only one field to be active at a time in RegionStore.
This isn't quite the correct behavior for unions, but it at least
would handle the case of "value goes in, value comes out" from the
same field.

RegionStore currently has a number of places where any access to a union
results in UnknownVal being returned. However, it is clearly missing
some cases, or the original issue wouldn't have occurred. It is probably
now safe to remove those changes, but that's a potentially destabilizing
change that should wait for more thorough testing.

Fixes PR14054.

llvm-svn: 165660
2012-10-10 21:31:21 +00:00
Ted Kremenek a808e165b2 Remove unnecessary ASTContext& parameter from SymExpr::getType().
llvm-svn: 164661
2012-09-26 06:00:14 +00:00
Anna Zaks 4278234360 [analyzer] Teach the analyzer about implicit initialization of statics
in ObjCMethods.

Extend FunctionTextRegion to represent ObjC methods as well as
functions. Note, it is not clear what type ObjCMethod region should
return. Since the type of the FunctionText region is not currently used,
defer solving this issue.

llvm-svn: 164046
2012-09-17 19:13:56 +00:00
Anna Zaks f6a5d793d2 [analyzer] Don't reimplement an existing function.
Thanks Jordan.

llvm-svn: 163762
2012-09-13 00:37:12 +00:00
Anna Zaks e663b80975 [analyzer] Teach UndefOrNullArgVisitor to track parent regions.
llvm-svn: 163748
2012-09-12 22:57:30 +00:00
Roman Divacky e637711ae0 Dont cast away const needlessly. Found by gcc48 -Wcast-qual.
llvm-svn: 163325
2012-09-06 15:59:27 +00:00
Jordan Rose 31c3fa9c24 [analyzer] Only adjust the type of 'this' when we devirtualize a method call.
With reinterpret_cast, we can get completely unrelated types in a region
hierarchy together; this was resulting in CXXBaseObjectRegions being layered
directly on an (untyped) SymbolicRegion, whose symbol was from a completely
different type hierarchy. This was what was causing the internal buildbot to
fail.

Reverts r161911, which merely masked the problem.

llvm-svn: 161960
2012-08-15 17:33:34 +00:00
Jordan Rose 95c841eaa0 [analyzer] A base class needs a complete definition to provide offsets.
No test case yet; trying to reduce one from a failing internal buildbot.

llvm-svn: 161911
2012-08-15 00:36:44 +00:00
Jordan Rose 07a7ed80cb [analyzer] Don't strip CXXBaseObjectRegions when checking dynamic_casts.
...and /do/ strip CXXBaseObjectRegions when casting to a virtual base class.

This allows us to enforce the invariant that a CXXBaseObjectRegion can always
provide an offset for its base region if its base region has a known class
type, by only allowing virtual bases and direct non-virtual bases to form
CXXBaseObjectRegions.

This does mean some slight problems for our modeling of dynamic_cast, which
needs to be resolved by finding a path from the current region to the class
we're trying to cast to.

llvm-svn: 161797
2012-08-13 22:11:34 +00:00
Jordan Rose a44a55a8f2 [analyzer] Cluster bindings in RegionStore by base region.
This should speed up activities that need to access bindings by cluster,
such as invalidation and dead-bindings cleaning. In some cases all we save
is the cost of building the region cluster map, but other times we can
actually avoid traversing the rest of the store.

In casual testing, this produced a speedup of nearly 10% analyzing SQLite,
with /less/ memory used.

llvm-svn: 161636
2012-08-09 22:55:51 +00:00
Jordan Rose c91e01bc11 [analyzer] Cache the "concrete offset base" for regions with symbolic offsets.
This makes it faster to access and invalidate bindings with symbolic offsets
by only computing this information once.

No intended functionality change.

llvm-svn: 161635
2012-08-09 22:55:37 +00:00
Jordan Rose d86b3bdb7a [analyzer] Clean up the printing of FieldRegions for leaks.
Unfortunately, generalized region printing is very difficult:
- ElementRegions are used both for casting and as actual elements.
- Accessing values through a pointer means going through an intermediate
  SymbolRegionValue; symbolic regions are untyped.
- Referring to implicitly-defined variables like 'this' and 'self' could be
  very confusing if they come from another stack frame.

We fall back to simply not printing the region name if we can't be sure it
will print well. This will allow us to improve in the future.

llvm-svn: 161512
2012-08-08 18:23:36 +00:00
Jordan Rose 3a80cec5e9 [analyzer] Revamp RegionStore to distinguish regions with symbolic offsets.
RegionStore currently uses a (Region, Offset) pair to describe the locations
of memory bindings. However, this representation breaks down when we have
regions like 'array[index]', where 'index' is unknown. We used to store this
as (SubRegion, 0); now we mark them specially as (SubRegion, SYMBOLIC).

Furthermore, ProgramState::scanReachableSymbols depended on the existence of
a sub-region map, but RegionStore's implementation doesn't provide for such
a thing. Moving the store-traversing logic of scanReachableSymbols into the
StoreManager allows us to eliminate the notion of SubRegionMap altogether.

This fixes some particularly awkward broken test cases, now in
array-struct-region.c.

llvm-svn: 161510
2012-08-08 18:23:27 +00:00
Jordan Rose d66bee3f76 [analyzer] Don't inline virtual calls unless we can devirtualize properly.
Previously we were using the static type of the base object to inline
methods, whether virtual or non-virtual. Now, we try to see if the base
object has a known type, and if so ask for its implementation of the method.

llvm-svn: 160094
2012-07-12 00:16:25 +00:00
Anna Zaks 3563fde6a0 [analyzer] Anti-aliasing: different heap allocations do not alias
Add a concept of symbolic memory region belonging to heap memory space.
When comparing symbolic regions allocated on the heap, assume that they
do not alias. 

Use symbolic heap region to suppress a common false positive pattern in
the malloc checker, in code that relies on malloc not returning the
memory aliased to other malloc allocations, stack.

llvm-svn: 158136
2012-06-07 03:57:32 +00:00
Jordan Rose 0da4e77880 [analyzer] Provide debug descriptions for all memory space regions.
Patch by Guillem Marpons!

llvm-svn: 158106
2012-06-06 20:47:00 +00:00
David Blaikie 40ed29730b Revert Decl's iterators back to pointer value_type rather than reference value_type
In addition, I've made the pointer and reference typedef 'void' rather than T*
just so they can't get misused. I would've omitted them entirely but
std::distance likes them to be there even if it doesn't use them.

This rolls back r155808 and r155869.

Review by Doug Gregor incorporating feedback from Chandler Carruth.

llvm-svn: 158104
2012-06-06 20:45:41 +00:00
Ted Kremenek c3da376fbc static analyzer: add inlining support for directly called blocks.
llvm-svn: 157833
2012-06-01 20:04:04 +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
David Blaikie 2d7c57ec1d Remove the ref/value inconsistency in filter_decl_iterator.
filter_decl_iterator had a weird mismatch where both op* and op-> returned T*
making it difficult to generalize this filtering behavior into a reusable
library of any kind.

This change errs on the side of value, making op-> return T* and op* return
T&.

(reviewed by Richard Smith)

llvm-svn: 155808
2012-04-30 02:36:29 +00:00
Anna Zaks fc2e153444 [analyzer] Malloc: Utter the name of the leaked variable.
Specifically, we use the last store of the leaked symbol in the leak diagnostic.
(No support for struct fields since the malloc checker doesn't track those
yet.)

+ Infrastructure to track the regions used in store evaluations.
This approach is more precise than iterating the store to
obtain the region bound to the symbol, which is used in RetainCount
checker. The region corresponds to what is uttered in the code in the
last store and we do not rely on the store implementation to support
this functionality.

llvm-svn: 153212
2012-03-21 19:45:08 +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
Ted Kremenek 3bc5372fae [analyzer] teach analyzer about ObjC literals, thus trimming out a false positive with the malloc() checker involving
comparing literal addresses to nil.

Fixes <rdar://problem/10579586>

llvm-svn: 151602
2012-02-28 00:56:05 +00:00
Ted Kremenek 1c95ef4e94 Teach analyzer that blocks with no captures are globals. Fixes <rdar://problem/10348049>.
llvm-svn: 150896
2012-02-18 22:41:01 +00:00
Benjamin Kramer 11764ab4c0 StaticAnalyzer: Move ObjC- and CXX-specific methods out of line so checkers that don't care about the language don't have to pull in all the headers.
llvm-svn: 149178
2012-01-28 12:06:22 +00:00
Anna Zaks 8158ef0dec [analyzer] Be less pessimistic about invalidation of global variables
as a result of a call.

Problem:
Global variables, which come in from system libraries should not be
invalidated by all calls. Also, non-system globals should not be
invalidated by system calls.

Solution:
The following solution to invalidation of globals seems flexible enough
for taint (does not invalidate stdin) and should not lead to too
many false positives. We split globals into 3 classes:

* immutable - values are preserved by calls (unless the specific
global is passed in as a parameter):
     A :  Most system globals and const scalars

* invalidated by functions defined in system headers:
     B: errno

* invalidated by all other functions (note, these functions may in
turn contain system calls):
     B: errno
     C: all other globals (which are not in A nor B)

llvm-svn: 147569
2012-01-04 23:54:01 +00:00
David Blaikie 68e081d606 Unweaken vtables as per http://llvm.org/docs/CodingStandards.html#ll_virtual_anch
llvm-svn: 146959
2011-12-20 02:48:34 +00:00
Ted Kremenek 81ce1c8a99 Rename AnalysisContext to AnalysisDeclContext. Not only is this name more accurate, but it frees up the name AnalysisContext for other uses.
llvm-svn: 142782
2011-10-24 01:32:45 +00:00
Benjamin Kramer b89514a9b8 Change operator<< for raw_ostream and NamedDecl to take a reference instead of a pointer.
Passing a pointer was a bad idea as it collides with the overload for void*.

llvm-svn: 141971
2011-10-14 18:45:37 +00:00
John McCall f937c023bf Rename TagDecl::isDefinition -> isCompleteDefinition
for better self-documenting code, since the semantics
are subtly different from getDefinition().

llvm-svn: 141355
2011-10-07 06:10:15 +00:00
Jeffrey Yasskin 0e9cdbbb06 Handle CXXTempObjectRegion in StackAddrEscapeChecker.
Also convert stack-addr-ps.cpp to use the analyzer instead of just Sema, now
that it doesn't crash, and extract the stack-block test into another file since
it errors, and that prevents the analyzer from running.

llvm-svn: 138613
2011-08-26 00:41:31 +00:00
Ted Kremenek 5ef32dbf2a Cleanup various declarations of 'Stmt*' to be 'Stmt *', etc. in libAnalyzer and libStaticAnalyzer[*]. It was highly inconsistent, and very ugly to look at.
llvm-svn: 137537
2011-08-12 23:37:29 +00:00
Chris Lattner 0e62c1cc0b remove unneeded llvm:: namespace qualifiers on some core types now that LLVM.h imports
them into the clang namespace.

llvm-svn: 135852
2011-07-23 10:55:15 +00:00
Ted Kremenek f8cbac4b91 Split 'include/clang/StaticAnalyzer' into 'include/clang/StaticAnalyzer/Core' and 'include/clang/StaticAnalyzer/Checkers'.
This layout matches lib/StaticAnalyzer, which corresponds to two StaticAnalyzer libraries.

llvm-svn: 125251
2011-02-10 01:03:03 +00:00
Argyrios Kyrtzidis fa0734ec4f [analyzer] Move the files in lib/StaticAnalyzer to lib/StaticAnalyzer/Core.
Eventually there will also be a lib/StaticAnalyzer/Frontend that will handle initialization and checker registration.
Yet another library to avoid cyclic dependencies between Core and Checkers.

llvm-svn: 125124
2011-02-08 22:30:36 +00:00