aboutsummaryrefslogtreecommitdiff
path: root/lib/StaticAnalyzer/Core
AgeCommit message (Collapse)Author
2013-03-13Remove stray space.Ted Kremenek
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176966 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-13[analyzer] Handle Objc Fast enumeration for "loop is executed 0 times".Ted Kremenek
Fixes <rdar://problem/12322528> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176965 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-11[analyzer] Look for calls along with lvalue nodes in trackNullOrUndefValue.Jordan Rose
r176737 fixed bugreporter::trackNullOrUndefValue to find nodes for an lvalue even if the rvalue node had already been collected. This commit extends that to call statement nodes as well, so that if a call is contained within implicit casts we can still track the return value. No test case because node reclamation is extremely finicky (dependent on how the AST and CFG are built, and then on our current reclamation rules, and /then/ on how many nodes were generated by the analyzer core and the current set of checkers). I consider this a low-risk change, though, and it will only happen in cases of reclamation when the rvalue node isn't available. <rdar://problem/13340764> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176829 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-09[analyzer] Make Suppress IDC checker aware that it might not start from the ↵Anna Zaks
same node it was registered at The visitor used to assume that the value it’s tracking is null in the first node it examines. This is not true. If we are registering the Suppress Inlined Defensive checks visitor while traversing in another visitor (such as FindlastStoreVisitor). When we restart with the IDC visitor, the invariance of the visitor does not hold since the symbol we are tracking no longer exists at that point. I had to pass the ErrorNode when creating the IDC visitor, because, in some cases, node N is neither the error node nor will be visible along the path (we had not finalized the path at that point and are dealing with ExplodedGraph.) We should revisit the other visitors which might not be aware that they might get nodes, which are later in path than the trigger point. This suppresses a number of inline defensive checks in JavaScriptCore. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176756 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-08[analyzer] Look for lvalue nodes when tracking a null pointer.Jordan Rose
r176010 introduced the notion of "interesting" lvalue expressions, whose nodes are guaranteed never to be reclaimed by the ExplodedGraph. This was used in bugreporter::trackNullOrUndefValue to find the region that contains the null or undef value being tracked. However, the /rvalue/ nodes (i.e. the loads from these lvalues that produce a null or undef value) /are/ still being reclaimed, and if we couldn't find the node for the rvalue, we just give up. This patch changes that so that we look for the node for either the rvalue or the lvalue -- preferring the former, since it lets us fall back to value-only tracking in cases where we can't get a region, but allowing the latter as well. <rdar://problem/13342842> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176737 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-08[analyzer] Don't rely on finding the correct return statement for suppression.Jordan Rose
Previously, ReturnVisitor waited to suppress a null return path until it had found the inlined "return" statement. Now, it checks up front whether the return value was NULL, and suppresses the warning right away if so. We still have to wait until generating the path notes to invalidate the bug report, or counter-suppression will never be triggered. (Counter-suppression happens while generating path notes, but the generation won't happen for reports already marked invalid.) This isn't actually an issue today because we never reclaim nodes for top-level statements (like return statements), but it could be an issue some day in the future. (But, no expected behavioral change and no new test case.) git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176736 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-07[analyzer] Clean up a few doc comments for ProgramState and CallEvent.Jordan Rose
No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176600 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-06[analyzer] IDC: Add config option; perform the idc check on first “null ↵Anna Zaks
node” rather than last “non-null”. The second modification does not lead to any visible result, but, theoretically, is what we should have been looking at to begin with since we are checking if the node was assumed to be null in an inlined function. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176576 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-05Silence a number of static analyzer warnings with assertions and such.Jordan Rose
No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176469 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-02[analyzer] Simple inline defensive checks suppressionAnna Zaks
Inlining brought a few "null pointer use" false positives, which occur because the callee defensively checks if a pointer is NULL, whereas the caller knows that the pointer cannot be NULL in the context of the given call. This is a first attempt to silence these warnings by tracking the symbolic value along the execution path in the BugReporter. The new visitor finds the node in which the symbol was first constrained to NULL. If the node belongs to a function on the active stack, the warning is reported, otherwise, it is suppressed. There are several areas for follow up work, for example: - How do we differentiate the cases where the first check is followed by another one, which does happen on the active stack? Also, this only silences a fraction of null pointer use warnings. For example, it does not do anything for the cases where NULL was assigned inside a callee. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176402 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-01[analyzer] Special-case bitfields when finding sub-region bindings.Jordan Rose
Previously we were assuming that we'd never ask for the sub-region bindings of a bitfield, since a bitfield cannot have subregions. However, unification of code paths has made that assumption invalid. While we could take advantage of this by just checking for the single possible binding, it's probably better to do the right thing, so that if/when we someday support unions we'll do the right thing there, too. This fixes a handful of false positives in analyzing LLVM. <rdar://problem/13325522> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176388 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-01[analyzer] Suppress paths involving a reference whose rvalue is null.Jordan Rose
Most map types have an operator[] that inserts a new element if the key isn't found, then returns a reference to the value slot so that you can assign into it. However, if the value type is a pointer, it will be initialized to null. This is usually no problem. However, if the user /knows/ the map contains a value for a particular key, they may just use it immediately: // From ClangSACheckersEmitter.cpp recordGroupMap[group]->Checkers In this case the analyzer reports a null dereference on the path where the key is not in the map, even though the user knows that path is impossible here. They could silence the warning by adding an assertion, but that means splitting up the expression and introducing a local variable. (Note that the analyzer has no way of knowing that recordGroupMap[group] will return the same reference if called twice in a row!) We already have logic that says a null dereference has a high chance of being a false positive if the null came from an inlined function. This patch simply extends that to references whose rvalues are null as well, silencing several false positives in LLVM. <rdar://problem/13239854> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176371 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-28[analyzer] RegionStore: collectSubRegionKeys -> collectSubRegionBindingsJordan Rose
By returning the (key, value) binding pairs, we save lookups afterwards. This also enables further work later on. No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176230 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-27[analyzer] Teach FindLastStoreBRVisitor to understand stores of the same value.Jordan Rose
Consider this case: int *p = 0; p = getPointerThatMayBeNull(); *p = 1; If we inline 'getPointerThatMayBeNull', we might know that the value of 'p' is NULL, and thus emit a null pointer dereference report. However, we usually want to suppress such warnings as error paths, and we do so by using FindLastStoreBRVisitor to see where the NULL came from. In this case, though, because 'p' was NULL both before and after the assignment, the visitor would decide that the "last store" was the initialization, not the re-assignment. This commit changes FindLastStoreBRVisitor to consider all PostStore nodes that assign to this region. This still won't catches changes made directly by checkers if they re-assign the same value, but it does handle the common case in user-written code and will trigger ReturnVisitor's suppression machinery as expected. <rdar://problem/13299738> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176201 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-27[analyzer] Turn on C++ constructor inlining by default.Jordan Rose
This enables constructor inlining for types with non-trivial destructors. The plan is to enable destructor inlining within the next month, but that needs further verification. <rdar://problem/12295329> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176200 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-27[analyzer] Add stop-gap patch to prevent assertion failure when analyzing ↵Ted Kremenek
LLVM codebase. This potentially reduces a performance optimization of throwing away PreStmtPurgeDeadSymbols nodes. I'll investigate the performance impact soon and see if we need something better. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176149 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-27[analyzer] If a struct has a partial lazy binding, its fields aren't Undef.Jordan Rose
This is essentially the same problem as r174031: a lazy binding for the first field of a struct may stomp on an existing default binding for the entire struct. Because of the way RegionStore is set up, we can't help but lose the top-level binding, but then we need to make sure that accessing one of the other fields doesn't come back as Undefined. In this case, RegionStore is now correctly detecting that the lazy binding we have isn't the right type, but then failing to follow through on the implications of that: we don't know anything about the other fields in the aggregate. This fix adds a test when searching for other kinds of default values to see if there's a lazy binding we rejected, and if so returns a symbolic value instead of Undefined. The long-term fix for this is probably a new Store model; see <rdar://problem/12701038>. Fixes <rdar://problem/13292559>. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176144 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-26[analyzer] Use 'MemRegion::printPretty()' instead of assuming the region is ↵Ted Kremenek
a VarRegion. Fixes PR15358 and <rdar://problem/13295437>. Along the way, shorten path diagnostics that say "Variable 'x'" to just be "'x'". By the context, it is obvious that we have a variable, and so this just consumes text space. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176115 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-26[analyzer] Don't look through casts when creating pointer temporaries.Jordan Rose
Normally, we need to look through derived-to-base casts when creating temporary object regions (added in r175854). However, if the temporary is a pointer (rather than a struct/class instance), we need to /preserve/ the base casts that have been applied. This also ensures that we really do create a new temporary region when we need to: MaterializeTemporaryExpr and lvalue CXXDefaultArgExprs. Fixes PR15342, although the test case doesn't include the crash because I couldn't isolate it. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176069 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-25[analyzer] Recover all PreStmtPurgeDeadSymbols nodes with a single successor ↵Ted Kremenek
or predecessor. These nodes are never consulted by any analyzer client code, so they are used only for machinery for removing dead bindings. Once successor nodes are generated they can be safely removed. This greatly reduces the amount of nodes that are generated in some case, lowering the memory regression when analyzing Sema.cpp introduced by r176010 from 14% to 2%. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176050 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-25[analyzer] Address Jordan's code review of r175857.Anna Zaks
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176043 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-25[analyzer] Handle reference parameters with default values.Jordan Rose
r175026 added support for default values, but didn't take reference parameters into account, which expect the default argument to be an lvalue. Use createTemporaryRegionIfNeeded if we can evaluate the default expr as an rvalue but the expected result is an lvalue. Fixes the most recent report of PR12915. The original report predates default argument support, so that can't be it. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176042 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-25[analyzer] Base regions may be invalid when layered on symbolic regions.Jordan Rose
While RegionStore checks to make sure casts on TypedValueRegions are valid, it does not do the same for SymbolicRegions, which do not have perfect type info anyway. Additionally, MemRegion::getAsOffset does not take a ProgramState, so it can't use dynamic type info to determine a better type for the regions. (This could also be dangerous if the type of a super-region changes!) Account for this by checking that a base object region is valid on top of a symbolic region, and falling back to "symbolic offset" mode if not. Fixes PR15345. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176034 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-25[analyzer] Relax assumption in FindLastStoreBRVisitor that the thing we are ↵Ted Kremenek
looking for is always a VarRegion. This was triggering assertion failures when analyzing the LLVM codebase. This is fallout from r175988. I've got delta chewing away on a test case, but I wanted the fix to go in now. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176011 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-25[analyzer] add the notion of an "interesting" lvalue expression for ↵Ted Kremenek
ExplodedNode pruning. r175988 modified the ExplodedGraph trimming algorithm to retain all nodes for "lvalue" expressions. This patch refines that notion to only "interesting" expressions that would be used for diagnostics. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@176010 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-24[analyzer] tracking stores/constraints now works for ObjC ivars or struct ↵Ted Kremenek
fields. This required more changes than I originally expected: - ObjCIvarRegion implements "canPrintPretty" et al - DereferenceChecker indicates the null pointer source is an ivar - bugreporter::trackNullOrUndefValue() uses an alternate algorithm to compute the location region to track by scouring the ExplodedGraph. This allows us to get the actual MemRegion for variables, ivars, fields, etc. We only hand construct a VarRegion for C++ references. - ExplodedGraph no longer drops nodes for expressions that are marked 'lvalue'. This is to facilitate the logic in the previous bullet. This may lead to a slight increase in size in the ExplodedGraph, which I have not measured, but it is likely not to be a big deal. I have validated each of the changed plist output. Fixes <rdar://problem/12114812> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175988 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-24Add "KnownSVal" to represent SVals that cannot be UnknownSVal.Ted Kremenek
This provides a few sundry cleanups, and allows us to provide a compile-time check for a case that was a runtime assertion. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175987 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-23Remove the CFGElement "Invalid" state.David Blaikie
Use Optional<CFG*> where invalid states were needed previously. In the one case where that's not possible (beginAutomaticObjDtorsInsert) just use a dummy CFGAutomaticObjDtor. Thanks for the help from Jordan Rose & discussion/feedback from Ted Kremenek and Doug Gregor. Post commit code review feedback on r175796 by Ted Kremenek. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175938 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-22[analyzer] Don't canonicalize the RecordDecl used in CXXBaseObjectRegion.Jordan Rose
This Decl shouldn't be the canonical Decl; it should be the Decl used by the CXXBaseSpecifier in the subclass. Unfortunately, that means continuing to throw getCanonicalDecl() on all comparisons. This fixes MemRegion::getAsOffset's use of ASTRecordLayout when redeclarations are involved. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175913 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-22[analyzer] Implement "Loop executed 0 times" diagnostic correctly.Ted Kremenek
Fixes <rdar://problem/13236549> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175863 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-22[analyzer] Place all inlining policy checks into one palceAnna Zaks
Previously, we had the decisions about inlining spread out over multiple functions. In addition to the refactor, this commit ensures that we will always inline BodyFarm functions as long as the Decl is available. This fixes false positives due to those functions not being inlined when no or minimal inlining is enabled such (as shallow mode). git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175857 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-22[analyzer] Make sure a materialized temporary matches its bindings.Jordan Rose
This is a follow-up to r175830, which made sure a temporary object region created for, say, a struct rvalue matched up with the initial bindings being stored into it. This does the same for the case in which the AST actually tells us that we need to create a temporary via a MaterializeObjectExpr. I've unified the two code paths and moved a static helper function onto ExprEngine. This also caused a bit of test churn, causing us to go back to describing temporary regions without a 'const' qualifier. This seems acceptable; it's our behavior from a few months ago. <rdar://problem/13265460> (part 2) git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175854 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-22Fix regression in modeling assignments of an address of a variable to ↵Ted Kremenek
itself. Fixes <rdar://problem/13226577>. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175852 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-22[analyzer] Fix buildbot by not reusing a variable name.Jordan Rose
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175848 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21[analyzer] Make sure a temporary object region matches its initial bindings.Jordan Rose
When creating a temporary region (say, when a struct rvalue is used as the base of a member expr), make sure we account for any derived-to-base casts. We don't actually record these in the LazyCompoundVal that represents the rvalue, but we need to make sure that the temporary region we're creating (a) matches the bindings, and (b) matches its expression. Most of the time this will do exactly the same thing as before, but it fixes spurious "garbage value" warnings introduced in r175234 by the use of lazy bindings to model trivial copy constructors. <rdar://problem/13265460> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175830 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21Simplify code to use castAs rather than getAs + assert.David Blaikie
Post commit review feedback on r175812 from Jordan Rose. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175826 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21Replace ProgramPoint llvm::cast support to be well-defined.David Blaikie
See r175462 for another example/more details. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175812 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21Replace CFGElement llvm::cast support to be well-defined.David Blaikie
See r175462 for another example/more details. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175796 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21StaticAnalyzer/Core: Suppress warnings. [-Wunused-variable, -Wunused-function]NAKAMURA Takumi
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175721 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21Whitespace.NAKAMURA Takumi
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175720 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21[analyzer] Record whether a base object region represents a virtual base.Jordan Rose
This allows MemRegion and MemRegionManager to avoid asking over and over again whether an class is a virtual base or a non-virtual base. Minor optimization/cleanup; no functionality change. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175716 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21[analyzer] Tidy up a few uses of Optional in RegionStore.Jordan Rose
Some that I just added needed conversion to use 'None', others looked better using Optional<SVal>::create. No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175714 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21Use None rather than Optional<T>() where possible.David Blaikie
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175705 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-21[analyzer] Tighten up safety in the use of lazy bindings.Jordan Rose
- When deciding if we can reuse a lazy binding, make sure to check if there are additional bindings in the sub-region. - When reading from a lazy binding, don't accidentally strip off casts or base object regions. This slows down lazy binding reading a bit but is necessary for type sanity when treating one class as another. A bit of minor refactoring allowed these two checks to be unified in a nice early-return-using helper function. <rdar://problem/13239840> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175703 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-20Include llvm::Optional in clang/Basic/LLVM.hDavid Blaikie
Post-commit CR feedback from Jordan Rose regarding r175594. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175679 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-20Use op-> directly rather than via Optional<T>::getPointer.David Blaikie
Post-commit CR feedback from Jordan Rose regarding r175594. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175677 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-20Replace SVal llvm::cast support to be well-defined.David Blaikie
See r175462 for another example/more details. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175594 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-20[analyzer] Account for the "interesting values" hash table resizing.Jordan Rose
RegionStoreManager::getInterestingValues() returns a pointer to a std::vector that lives inside a DenseMap, which is constructed on demand. However, constructing one such value can lead to constructing another value, which will invalidate the reference created earlier. Fixed by delaying the new entry creation until the function returns. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175582 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-19[analyzer] Don't accidentally strip off base object regions for lazy bindings.Jordan Rose
If a base object is at a 0 offset, RegionStoreManager may find a lazy binding for the entire object, then try to attach a FieldRegion or grandparent CXXBaseObjectRegion on top of that (skipping the intermediate region). We now preserve as many layers of base object regions necessary to make the types match. <rdar://problem/13239840> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175556 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-15[analyzer] Don't assert when mixing reinterpret_cast and derived-to-base casts.Jordan Rose
This just adds a very simple check that if a DerivedToBase CastExpr is operating on a value with known C++ object type, and that type is not the base type specified in the AST, then the cast is invalid and we should return UnknownVal. In the future, perhaps we can have a checker that specifies that this is illegal, but we still shouldn't assert even if the user turns that checker off. PR14872 git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175239 91177308-0d34-0410-b5e6-96231b3b80d8