Commit Graph

621 Commits

Author SHA1 Message Date
Daniel Jasper 6b5a4fcc07 Prevent unused-variable warning in optimized builds.
llvm-svn: 160257
2012-07-16 10:25:15 +00:00
Ted Kremenek b50e716bac Refine CFG so that '&&' and '||' don't lead to extra confluence points when used in a branch, but
instead push the terminator for the branch down into the basic blocks of the subexpressions of '&&' and '||'
respectively.  This eliminates some artifical control-flow from the CFG and results in a more
compact CFG.

Note that this patch only alters the branches 'while', 'if' and 'for'.  This was complex enough for
one patch.  The remaining branches (e.g., do...while) can be handled in a separate patch, but they
weren't immediately tackled because they were less important.

It is possible that this patch introduces some subtle bugs, particularly w.r.t. to destructor placement.
I've tried to audit these changes, but it is also known that the destructor logic needs some refinement
in the area of '||' and '&&' regardless (i.e., their are known bugs).

llvm-svn: 160218
2012-07-14 05:04:10 +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
Jordan Rose 8889cf008d [analyzer] Add debug.DumpCalls, which prints out any CallEvents it sees.
This is probably not so useful yet because it is not path-sensitive, though
it does try to show inlining with indentation.

This also adds a dump() method to CallEvent, which should be useful for
debugging.

llvm-svn: 160030
2012-07-10 23:56:23 +00:00
Jordan Rose eab627b951 [analyzer] Construct stack variables directly in their VarDecl.
Also contains a number of tweaks to inlining that are necessary
for constructors and destructors. (I have this enabled on a private
branch, but it is very much unstable.)

llvm-svn: 160023
2012-07-10 22:08:01 +00:00
Jordan Rose d1d54aa131 [analyzer] Use CallEvent for building inlined stack frames.
In order to accomplish this, we now build the callee's stack frame
as part of the CallEnter node, rather than the subsequent BlockEdge node.
This should not have any effect on perceived behavior or diagnostics.

This makes it safe to re-enable inlining of member overloaded operators.

llvm-svn: 160022
2012-07-10 22:07:57 +00:00
Jordan Rose fbe6dba15a [analyzer] Make CallEnter, CallExitBegin, and CallExitEnd not be StmtPoints
These ProgramPoints are used in inlining calls,
and not all calls have associated statements anymore.

llvm-svn: 160021
2012-07-10 22:07:52 +00:00
Jordan Rose 4ee71b8a18 [analyzer] Add a CXXDestructorCall CallEvent.
While this work is still fairly tentative (destructors are still left out of
the CFG by default), we now handle destructors in the same way as any other
calls, instead of just automatically trying to inline them.

llvm-svn: 160020
2012-07-10 22:07:47 +00:00
Jordan Rose 681cce9908 [analyzer] Add new PreImplicitCall and PostImplicitCall ProgramPoints.
These are currently unused, but are intended to be used in lieu of PreStmt
and PostStmt when the call is implicit (e.g. an automatic object destructor).

This also modifies the Data1 field of ProgramPoints to allow storing any
pointer-sized value, as opposed to only aligned pointers. This is necessary
to store SourceLocations.

There is currently no BugReporter support for these; they should be skipped
over in any diagnostic output.

This commit also tags checkers that currently rely on function calls only
occurring at StmtPoints.

llvm-svn: 160019
2012-07-10 22:07:42 +00:00
Jordan Rose e04395e2f4 [analyzer] When inlining, make sure we use the definition decl.
This was a regression introduced during the CallEvent changes; a call to
FunctionDecl::hasBody was also being used to replace the decl found by
lookup with the actual definition. To keep from making this mistake again
(particularly if/when we start inlining Objective-C methods), this commit
adds a "getDefinition()" method to CallEvent, which should do the right
thing under any circumstances.

llvm-svn: 159940
2012-07-09 16:54:49 +00:00
Jordan Rose 3f89e0ec93 [analyzer] Be careful about LazyCompoundVals, which may be for the first field.
We use LazyCompoundVals to avoid copying the contents of structs and arrays
around in the store, and when we need to pass a struct around that already
has a LazyCompoundVal we just use the original one. However, it's possible
that the first field of a struct may have a LazyCompoundVal of its own, and
we currently can't distinguish a LazyCompoundVal for the first element of a
struct from a LazyCompoundVal for the entire struct. In this case we should
just drop the optimization and make a new LazyCompoundVal that encompasses
the old one.

PR13264 / <rdar://problem/11802440>

llvm-svn: 159866
2012-07-06 21:59:56 +00:00
Dmitri Gribenko ec92531c29 Implement AST classes for comments, a real parser for Doxygen comments and a
very simple semantic analysis that just builds the AST; minor changes for lexer
to pick up source locations I didn't think about before.

Comments AST is modelled along the ideas of HTML AST: block and inline content.

* Block content is a paragraph or a command that has a paragraph as an argument
  or verbatim command.
* Inline content is placed within some block.  Inline content includes plain
  text, inline commands and HTML as tag soup.

llvm-svn: 159790
2012-07-06 00:28:32 +00:00
Benjamin Kramer 1ea8e092be Drop the ASTContext.h include from Stmt.h and fix up transitive users.
This required moving the ctors for IntegerLiteral and FloatingLiteral out of
line which shouldn't change anything as they are usually called through Create
methods that are already out of line.

ASTContext::Deallocate has been a nop for a long time, drop it from ASTVector
and make it independent from ASTContext.h

Pass the StorageAllocator directly to AccessedEntity so it doesn't need to
have a definition of ASTContext around.

llvm-svn: 159718
2012-07-04 17:04:04 +00:00
Jordan Rose 017591ab45 [analyzer] For now, don't inline non-static member overloaded operators.
Our current inlining support (specifically RegionStore::enterStackFrame)
doesn't know that calls to overloaded operators may be calls to non-static
member functions, and that in these cases the first argument should be
treated as 'this'. This caused incorrect results and sometimes crashes.

The long-term fix will be to rewrite RegionStore::enterStackFrame to use
CallEvent and its subclasses, but for now we can just disable these
problematic calls by classifying them under a new CallEvent,
CXXMemberOperatorCall.

llvm-svn: 159692
2012-07-03 22:55:57 +00:00
Jordan Rose a4ee064cf3 [analyzer] Introduce CXXAllocatorCall to handle placement arg invalidation.
This is NOT full-blown support for operator new, but removes some nasty
duplicated code introduced in r158784.

llvm-svn: 159608
2012-07-02 22:21:47 +00:00
Jordan Rose 62146f67b7 Revert "Remove unused member (& consequently unused parameter) in SA's Call code."
...and instead add an accessor. We're not using this today, but it's something
that should probably stay in the source for potential clients, and it doesn't
cost a lot. (ObjCPropertyAccess is only created on the stack, and right now
there's only ever one alive at a time.)

This reverts r159581 / commit 8e674e1da34a131faa7d43dc3fcbd6e49120edbe.

llvm-svn: 159595
2012-07-02 21:41:53 +00:00
David Blaikie 977a35644e Remove unused member (& consequently unused parameter) in SA's Call code.
This member became unused in r159559.

llvm-svn: 159581
2012-07-02 20:44:57 +00:00
Ted Kremenek de21a1c964 Bail out the LiveVariables analysis when the CFG is very large, as
we are encountering some scalability issues with memory usage.   The
appropriate long term fix is to make the analysis more scalable, but
this will at least prevent the analyzer swapping when
analyzing very large functions.

llvm-svn: 159578
2012-07-02 20:21:52 +00:00
Jordan Rose afe7c2c2bf [analyzer] Add generic preCall and postCall checks.
llvm-svn: 159562
2012-07-02 19:28:16 +00:00
Jordan Rose f3c12ac3b1 [analyzer] Convert CXXConstructExpr over to use CallEvent for evaluation.
llvm-svn: 159561
2012-07-02 19:28:12 +00:00
Jordan Rose cbeef55886 [analyzer] Use CallEvent for inlining and call default-evaluation.
llvm-svn: 159560
2012-07-02 19:28:09 +00:00
Jordan Rose 547060b30b [analyzer] Finish replacing ObjCMessage with ObjCMethodDecl and friends.
The preObjCMessage and postObjCMessage callbacks now take an ObjCMethodCall
argument, which can represent an explicit message send (ObjCMessageSend) or an
implicit message generated by a property access (ObjCPropertyAccess).

llvm-svn: 159559
2012-07-02 19:28:04 +00:00
Jordan Rose 6bad4905d7 [analyzer] Begin replacing ObjCMessage with ObjCMethodCall and friends.
Previously, the CallEvent subclass ObjCMessageInvocation was just a wrapper
around the existing ObjCMessage abstraction (over message sends and property
accesses). Now, we have abstract CallEvent ObjCMethodCall with subclasses
ObjCMessageSend and ObjCPropertyAccess.

In addition to removing yet another wrapper object, this should make it easy
to add a ObjCSubscriptAccess call event soon.

llvm-svn: 159558
2012-07-02 19:27:56 +00:00
Jordan Rose 7ab0182e33 [analyzer] Move the last bits of CallOrObjCMessage over to CallEvent.
This involved refactoring some common pointer-escapes code onto CallEvent,
then having MallocChecker use those callbacks for whether or not to consider
a pointer's /ownership/ as escaping. This still needs to be pinned down, and
probably we want to make the new argumentsMayEscape() function a little more
discerning (content invalidation vs. ownership/metadata invalidation), but
this is a good improvement.

As a bonus, also remove CallOrObjCMessage from the source completely.

llvm-svn: 159557
2012-07-02 19:27:51 +00:00
Jordan Rose 742920c8e7 [analyzer] Add a new abstraction over all types of calls: CallEvent
This is intended to replace CallOrObjCMessage, and is eventually intended to be
used for anything that cares more about /what/ is being called than /how/ it's
being called. For example, inlining destructors should be the same as inlining
blocks, and checking __attribute__((nonnull)) should apply to the allocator
calls generated by operator new.

llvm-svn: 159554
2012-07-02 19:27:35 +00:00
Jordan Rose 42ee04d00a [analyzer] Add a test that we are, in fact, doing a DFS on the ExplodedGraph.
Previously:
...the comment said DFS...
...the WorkList being instantiated said BFS...
...and the implementation was actually DFS...
...due to an unintentional change in 2010...
...and everything kept working anyway.

This fixes our std::deque implementation of BFS, but switches back to a
SmallVector-based implementation of DFS.

We should probably still investigate the ramifications of DFS vs. BFS,
especially for large functions (and especially when we hit our block path
limit), since this might completely change our memory use. It can also mask
some bugs and reveal others depending on when we halt analysis. But at least
we will not have this kind of little mistake creep in again.

llvm-svn: 159397
2012-06-29 00:33:10 +00:00
Jordan Rose 88be136cff [analyzer] Remove unneeded helper function (it's in ASTContext.h)
llvm-svn: 159244
2012-06-27 00:51:16 +00:00
Ted Kremenek 72b3452c2b Implement initial static analysis inlining support for C++ methods.
llvm-svn: 159047
2012-06-22 23:55:50 +00:00
Anna Zaks 301e0d6074 [analyzer] Remove a statistic - it's too expensive.
(Committed in r159038 by mistake.)

llvm-svn: 159040
2012-06-22 22:24:45 +00:00
Anna Zaks 7aa3687bb6 [analyzer]scan-build: report the total number of steps analyzer performs
This would be useful to investigate performance issues.

llvm-svn: 159038
2012-06-22 22:08:12 +00:00
Anna Zaks ce519153fd [analyzer] Report the cumulative number of steps the analyzer performs.
llvm-svn: 159036
2012-06-22 22:08:06 +00:00
Jordan Rose ef1c7ae323 [analyzer] Check for +raise:format: on subclasses of NSException as well.
We don't handle exceptions yet, so we treat them as sinks. ExprEngine
hardcodes messages that are known to raise Objective-C exceptions like -raise,
but it was only checking for +raise:format: and +raise:format:arguments: on
NSException itself, not subclasses.

<rdar://problem/11724201>

llvm-svn: 159010
2012-06-22 17:15:58 +00:00
Chandler Carruth 28969b4139 Remove a goofy CMake hack and use the standard CMake facilities to
express library-level dependencies within Clang.

This is no more verbose really, and plays nicer with the rest of the
CMake facilities. It should also have no change in functionality.

llvm-svn: 158888
2012-06-21 01:30:21 +00:00
Jordan Rose 44320367ac [analyzer] Invalidate placement args; return the pointer given to placement new
The default global placement new just returns the pointer it is given.
Note that other custom 'new' implementations with placement args are not
guaranteed to do this.

In addition, we need to invalidate placement args, since they may be updated by
the allocator function. (Also, right now we don't properly handle the
constructor inside a CXXNewExpr, so we need to invalidate the placement args
just so that callers know something changed!)

This invalidation is not perfect because CallOrObjCMessage doesn't support
CXXNewExpr, and all of our invalidation callbacks expect that if there's no
CallOrObjCMessage, the invalidation is happening manually (e.g. by a direct
assignment) and shouldn't affect checker-specific metadata (like malloc state);
hence the malloc test case in new-fail.cpp. But region values are now
properly invalidated, at least.

The long-term solution to this problem is to rework CallOrObjCMessage into
something more general, rather than the morass of branches it is today.

<rdar://problem/11679031>

llvm-svn: 158784
2012-06-20 01:32:01 +00:00
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 e42412be39 [analyzer] Return an UnknownVal when we try to get the binding for a VLA.
This happens in C++ mode right at the declaration of a struct VLA;
MallocChecker sees a bind and tries to get see if it's an escaping bind.
It's likely that our handling of this is still incomplete, but it fixes a
crash on valid without disturbing anything else for now.

llvm-svn: 158587
2012-06-16 01:28:00 +00:00
James Dennett 1bc5f0c7ef Documentation cleanup: fix a type, LocatioinE -> LocationE
llvm-svn: 158566
2012-06-15 22:32:14 +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
Chad Rosier 32503020a4 Etch out the code path for MS-style inline assembly.
llvm-svn: 158325
2012-06-11 20:47:18 +00:00
Jordan Rose efef760214 [analyzer] Add ObjCLoopChecker: objects from NSArray et al are non-nil.
While collections containing nil elements can still be iterated over in an
Objective-C for-in loop, the most common Cocoa collections -- NSArray,
NSDictionary, and NSSet -- cannot contain nil elements. This checker adds
that assumption to the analyzer state.

This was the cause of some minor false positives concerning CFRelease calls
on objects in an NSArray.

llvm-svn: 158319
2012-06-11 16:40:41 +00:00
Anna Zaks b60908db3a [analyzer] Add experimental "issue hash" to the plist diagnostic.
CmpRuns.py can be used to compare issues from different analyzer runs.
Since it uses the issue line number to unique 2 issues, adding a new
line to the beginning of a file makes all issues in the file reported as
new. 

The hash will be an opaque value which could be used (along with the
function name) by CmpRuns to identify the same issues. This way, we only
fail to identify the same issue from two runs if the function it appears
in changes (not perfect, but much better than nothing).

llvm-svn: 158180
2012-06-08 00:04:43 +00:00
Anna Zaks a7dcc996a9 [analyzer] Fixit for r158136.
I falsely assumed that the memory spaces are equal when we reach this
point, they might not be when memory space of one or more is stack or
Unknown. We don't want a region from Heap space alias something with
another memory space.

llvm-svn: 158165
2012-06-07 20:18:08 +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
Benjamin Kramer d1d76b2da7 Remove unused private member variables found by clang's new -Wunused-private-field.
llvm-svn: 158086
2012-06-06 17:32:50 +00:00
Ted Kremenek 54baf2e57d PlistDiagnostics: force the ranges for control-flow edges to be single locations, forcing
adjacent edges to have compatible ranges.  This simplifies the layout logic for some clients.

llvm-svn: 158028
2012-06-05 22:00:52 +00:00
Anna Zaks 4ff9097fcc [analyzer] Fix a diagnostics bug which lead to a crash on the buildbot.
This bug was triggered by r157851. It only happens in the case where we
don't perform optimal diagnostic pruning.

llvm-svn: 157950
2012-06-04 21:03:31 +00:00