Commit Graph

1087 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 6cd16c5152 [analyzer] Guard against C++ member functions that look like system functions.
C++ method calls and C function calls both appear as CallExprs in the AST.
This was causing crashes for an object that had a 'free' method.

<rdar://problem/11822244>

llvm-svn: 160029
2012-07-10 23:13:01 +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
Anna Zaks 8698dd63d7 [analyzer] Remove redundant check (scalar type is a superset of integer)
PR13319 Reported by Jozsef Mihalicza.

llvm-svn: 159996
2012-07-10 16:27:55 +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
Anna Zaks 40b87fc1f9 [analyzer] Add a statistic for maximum CFG size and a script to summarize analyzer stats from scan-build output.
llvm-svn: 159776
2012-07-05 20:44:02 +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 e8d5567426 [analyzer] If 'super' is known to be nil, we can still mark its range.
llvm-svn: 159596
2012-07-02 21:41:56 +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
Ted Kremenek 146ef384da Fix subtle bug in AnalysisConsumer where we would not analyze functions whose parent
in the call graph had been inlined but for whatever reason we did not inline some
of its callees.

Also, fix a related traversal bug where we meant to do a BFS of the callgraph but
instead were doing a DFS.

llvm-svn: 159577
2012-07-02 20:21:48 +00:00
Jordan Rose 682b31621f [analyzer] Convert existing checkers to use check::preCall and check::postCall.
llvm-svn: 159563
2012-07-02 19:28:21 +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 2995349f3e [analyzer] Convert CallAndMessageChecker and ObjCSelfInitChecker to CallEvent.
Both of these got uglier rather than cleaner because we don't have preCall and
postCall yet; properly wrapping a CallExpr in a CallEvent requires doing a bit
of deconstruction on the callee. Even when we have preCall and postCall we may
want to expose the current CallEvent to pre/postStmt<CallExpr>.

llvm-svn: 159556
2012-07-02 19:27:46 +00:00
Jordan Rose eec1539a31 [analyzer] Convert RetainCountChecker to use CallEvent as much as possible.
This ended allowing quite a bit of cleanup, and some minor changes.

- CallEvent makes it easy to use hasNonZeroCallbackArg more aggressively, which
  we check in order to avoid false positives with callbacks that might release
  the object.
- In order to support this for functions which consume their arguments, there
  are two new ArgEffects: DecRefAndStopTracking and DecRefMsgAndStopTracking.
  These act just like StopTracking, except that if the object only had a
  return count of +1 it's now considered released instead (so we still get
  use-after-free messages).
- On the plus side, we no longer have to special-case
  +[NSObject performSelector:withObject:afterDelay:] and friends.
- The use of IdentifierInfos in the method summary cache is now hidden; only
  the ObjCInterfaceDecl gets passed around most of the time.
- Since we cache all "simple" summaries and check every function call, there is
  no real benefit to having NULL stand in for default summaries anymore.
- Whitespace, unused methods, etc.

Even more simplification to come when we get check::postCall and can unify all
these other post* checks.

llvm-svn: 159555
2012-07-02 19:27:43 +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
Ted Kremenek afddb9c81c Revert "Tweak insecureAPI analyzer checks to have the ability to be individually disabled."
Jordan Rose corrected me that this actually isn't needed.

llvm-svn: 159462
2012-06-29 21:01:35 +00:00
Ted Kremenek a33b078e73 Tweak insecureAPI analyzer checks to have the ability to be individually disabled.
The solution is a bit inefficient: it creates N checkers, one for each check, and
each check does a dispatch on the function name.  This is redundant, but we can fix
this once we have the proper ability to enable/disable subchecks.

Fixes <rdar://problem/11780180>.

llvm-svn: 159459
2012-06-29 20:44:58 +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 89b917e399 [analyzer] RetainCountChecker: remove unused SelfOwn ArgEffect kind.
llvm-svn: 159245
2012-06-27 00:51:18 +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
Jordan Rose 4688e60861 [analyzer] Be careful about implicitly-declared operator new/delete. (PR13090)
The implicit global allocation functions do not have valid source locations,
but we still want to treat them as being "system header" functions for the
purposes of how they affect program state.

llvm-svn: 159160
2012-06-25 20:48:28 +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 26712c845e [analyzer] Teach malloc checker that initWith[Bytes|Characters}NoCopy
relinquish memory.

llvm-svn: 159043
2012-06-22 22:42:30 +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 e4b6d5e1c1 [analyzer] Fixup to r158958.
llvm-svn: 159037
2012-06-22 22:08:09 +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
Anna Zaks 0d6989bd10 [analyzer] Malloc: Warn about use-after-free when memory ownership was
transfered with dataWithBytesNoCopy.

llvm-svn: 158958
2012-06-22 02:04:31 +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
Anna Zaks 886dfb8cfa [analyzer] Malloc leak false positive: Allow xpc context to escape.
llvm-svn: 158875
2012-06-20 23:35:57 +00:00
Anna Zaks 9050ffd57c [analyzer] Malloc: cleanup, disallow free on relinquished memory.
This commits sets the grounds for more aggressive use after free
checking. We will use the Relinquished sate to denote that someone
else is now responsible for releasing the memory.

llvm-svn: 158850
2012-06-20 20:57:46 +00:00