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path: root/lib/StaticAnalyzer/Core/RegionStore.cpp
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2013-05-06[analyzer] Remove now-unused bindCompoundLiteral helper function.Jordan Rose
The one user has been changed to use getLValue on the compound literal expression and then use the normal bindLoc to assign a value. No need to special case this in the StoreManager. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@181214 91177308-0d34-0410-b5e6-96231b3b80d8
2013-05-01[analyzer] Consolidate constant evaluation logic in SValBuilder.Jordan Rose
Previously, this was scattered across Environment (literal expressions), ExprEngine (default arguments), and RegionStore (global constants). The former special-cased several kinds of simple constant expressions, while the latter two deferred to the AST's constant evaluator. Now, these are all unified as SValBuilder::getConstantVal(). To keep Environment fast, the special cases for simple constant expressions have been left in, but the main benefits are that (a) unusual constants like ObjCStringLiterals now work as default arguments and global constant initializers, and (b) we're not duplicating code between ExprEngine and RegionStore. This actually caught a bug in our test suite, which is awesome: we stop tracking allocated memory if it's passed as an argument along with some kind of callback, but not if the callback is 0. We were testing this in a case where the callback parameter had a default value, but that value was 0. After this change, the analyzer now (correctly) flags that as a leak! <rdar://problem/13773117> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180894 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-24[analyzer] Refactoring + explanatory comment.Anton Yartsev
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@180181 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-18[analyzer] "Force" LazyCompoundVals on bind when they are simple enough.Jordan Rose
The analyzer uses LazyCompoundVals to represent rvalues of aggregate types, most importantly structs and arrays. This allows us to efficiently copy around an entire struct, rather than doing a memberwise load every time a struct rvalue is encountered. This can also keep memory usage down by allowing several structs to "share" the same snapshotted bindings. However, /lookup/ through LazyCompoundVals can be expensive, especially since they can end up chaining back to the original value. While we try to reuse LazyCompoundVals whenever it's safe, and cache information about this transitivity, the fact is it's sometimes just not a good idea to perpetuate LazyCompoundVals -- the tradeoffs just aren't worth it. This commit changes RegionStore so that binding a LazyCompoundVal to struct will do a memberwise copy if the struct is simple enough. Today's definition of "simple enough" is "up to N scalar members" (see below), but that could easily be changed in the future. This is enough to bring the test case in PR15697 back down to a manageable analysis time (within 20% of its original time, in an unfair test where the new analyzer is not compiled with LTO). The actual value of "N" is controlled by a new -analyzer-config option, 'region-store-small-struct-limit'. It defaults to "2", meaning structs with zero, one, or two scalar members will be considered "simple enough" for this code path. It's worth noting that a more straightforward implementation would do this on load, not on bind, and make use of the structure we already have for this: CompoundVal. A long time ago, this was actually how RegionStore modeled aggregate-to-aggregate copies, but today it's only used for compound literals. Unfortunately, it seems that we've special-cased LazyCompoundVal in certain places (such as liveness checks) but failed to similarly special-case CompoundVal in all of them. Until we're confident that CompoundVal is handled properly everywhere, this solution is safer, since the entire optimization is just an implementation detail of RegionStore. <rdar://problem/13599304> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179767 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-15[analyzer] Be lazy about struct/array global invalidation too.Jordan Rose
Structs and arrays can take advantage of the single top-level global symbol optimization (described in the previous commit) just as well as scalars. No intended behavioral change. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179555 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-15[analyzer] Re-enable using global regions as a symbolic base.Jordan Rose
Now that we're invalidating global regions properly, we want to continue taking advantage of a particular optimization: if all global regions are invalidated together, we can represent the bindings of each region with a "derived region value" symbol. Essentially, this lazily links each global region with a single symbol created at invalidation time, rather than binding each region with a new symbolic value. We used to do this, but haven't been for a while; the previous commit re-enabled this code path, and this handles the fallout. <rdar://problem/13464044> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179554 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-15[analyzer] Properly invalidate global regions on opaque function calls.Jordan Rose
This fixes a regression where a call to a function we can't reason about would not actually invalidate global regions that had explicit bindings. void test_that_now_works() { globalInt = 42; clang_analyzer_eval(globalInt == 42); // expected-warning{{TRUE}} invalidateGlobals(); clang_analyzer_eval(globalInt == 42); // expected-warning{{UNKNOWN}} } This has probably been around since the initial "cluster" refactoring of RegionStore, if not longer. <rdar://problem/13464044> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179553 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-09[analyzer] Replace isIntegerType() with isIntegerOrEnumerationType().Jordan Rose
Previously, the analyzer used isIntegerType() everywhere, which uses the C definition of "integer". The C++ predicate with the same behavior is isIntegerOrUnscopedEnumerationType(). However, the analyzer is /really/ using this to ask if it's some sort of "integrally representable" type, i.e. it should include C++11 scoped enumerations as well. hasIntegerRepresentation() sounds like the right predicate, but that includes vectors, which the analyzer represents by its elements. This commit audits all uses of isIntegerType() and replaces them with the general isIntegerOrEnumerationType(), except in some specific cases where it makes sense to exclude scoped enumerations, or any enumerations. These cases now use isIntegerOrUnscopedEnumerationType() and getAs<BuiltinType>() plus BuiltinType::isInteger(). isIntegerType() is hereby banned in the analyzer - lib/StaticAnalysis and include/clang/StaticAnalysis. :-) Fixes real assertion failures. PR15703 / <rdar://problem/12350701> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@179081 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-03[analyzer] Fix typo.Anna Zaks
Thanks Jordan! git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178683 91177308-0d34-0410-b5e6-96231b3b80d8
2013-04-02[analyzer] Teach invalidateRegions that regions within LazyCompoundVal need ↵Anna Zaks
to be invalidated Refactor invalidateRegions to take SVals instead of Regions as input and teach RegionStore about processing LazyCompoundVal as a top-level “escaping” value. This addresses several false positives that get triggered by the NewDelete checker, but the underlying issue is reproducible with other checkers as well (for example, MallocChecker). git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178518 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-28[analyzer] Add support for escape of const pointers and use it to allow ↵Anna Zaks
“newed” pointers to escape Add a new callback that notifies checkers when a const pointer escapes. Currently, this only works for const pointers passed as a top level parameter into a function. We need to differentiate the const pointers escape from regular escape since the content pointed by const pointer will not change; if it’s a file handle, a file cannot be closed; but delete is allowed on const pointers. This should suppress several false positives reported by the NewDelete checker on llvm codebase. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178310 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-26[analyzer] micro optimization as per Jordan’s feedback on r177905.Anna Zaks
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@178062 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-25[analyzer] Set concrete offset bindings to UnknownVal when processing ↵Anna Zaks
symbolic offset binding, even if no bindings are present. This addresses an undefined value false positive from concreteOffsetBindingIsInvalidatedBySymbolicOffsetAssignment. Fixes PR14877; radar://12991168. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177905 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-23[analyzer] Correct the stale comment.Anna Zaks
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177788 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-20[analyzer] Appease buildbots: include template arguments in base class ref.Jordan Rose
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177583 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-20[analyzer] Don't invalidate globals when there's no call involved.Jordan Rose
This fixes some mistaken condition logic in RegionStore that caused global variables to be invalidated when /any/ region was invalidated, rather than only as part of opaque function calls. This was only being used by CStringChecker, and so users will now see that strcpy() and friends do not invalidate global variables. Also, add a test case we don't handle properly: explicitly-assigned global variables aren't being invalidated by opaque calls. This is being tracked by <rdar://problem/13464044>. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177572 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-20[analyzer] Invalidate regions indirectly accessible through const pointers.Jordan Rose
In this case, the value of 'x' may be changed after the call to indirectAccess: struct Wrapper { int *ptr; }; void indirectAccess(const Wrapper &w); void test() { int x = 42; Wrapper w = { x }; clang_analyzer_eval(x == 42); // TRUE indirectAccess(w); clang_analyzer_eval(x == 42); // UNKNOWN } This is important for modelling return-by-value objects in C++, to show that the contents of the struct are escaping in the return copy-constructor. <rdar://problem/13239826> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177570 91177308-0d34-0410-b5e6-96231b3b80d8
2013-03-19[analyzer] Do not believe lazy binding when symbolic region types do not matchAnna Zaks
This fixes a crash when analyzing LLVM that was exposed by r177220 (modeling of trivial copy/move assignment operators). When we look up a lazy binding for “Builder”, we see the direct binding of Loc at offset 0. Previously, we believed the binding, which led to a crash. Now, we do not believe it as the types do not match. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@177453 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
2013-02-28[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] 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
2013-02-25[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
2013-02-21[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] Cache the bindings accessible through a LazyCompoundVal.Jordan Rose
This means we don't have to recompute them all later for every removeDeadSymbols check. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175233 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-15[analyzer] Tweak LazyCompoundVal reuse check to ignore qualifiers.Jordan Rose
This is optimization only; no behavioral change. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175231 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-15[analyzer] Use collectSubRegionKeys to make removeDeadBindings faster.Jordan Rose
Previously, whenever we had a LazyCompoundVal, we crawled through the entire store snapshot looking for bindings within the LCV's region. Now, we just ask for the subregion bindings of the lazy region and only visit those. This is an optimization (so no test case), but it may allow us to clean up more dead bindings than we were previously. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175230 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-15[analyzer] Refactor RegionStore's sub-region bindings traversal.Jordan Rose
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. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175228 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-14[analyzer] Try constant-evaluation for all variables, not just globals.Jordan Rose
In C++, constants captured by lambdas (and blocks) are not actually stored in the closure object, since they can be expanded at compile time. In this case, they will have no binding when we go to look them up. Previously, RegionStore thought they were uninitialized stack variables; now, it checks to see if they are a constant we know how to evaluate, using the same logic as r175026. This particular code path is only for scalar variables. Constant arrays and structs are still unfortunately unhandled; we'll need a stronger solution for those. This may have a small performance impact, but only for truly-undefined local variables, captures in a non-inlined block, and non-constant globals. Even then, in the non-constant case we're only doing a quick type check. <rdar://problem/13105553> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175194 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-13[analyzer] Use Clang's evaluation for global constants and default arguments.Jordan Rose
Previously, we were handling only simple integer constants for globals and the smattering of implicitly-valued expressions handled by Environment for default arguments. Now, we can use any integer constant expression that Clang can evaluate, in addition to everything we handled before. PR15094 / <rdar://problem/12830437> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175026 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-13[analyzer] Use makeZeroVal in RegionStore's lazy evaluation of statics.Jordan Rose
No functionality change. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@175025 91177308-0d34-0410-b5e6-96231b3b80d8
2013-02-01[analyzer] Reuse a LazyCompoundVal if its type matches the new region.Jordan Rose
This allows us to keep from chaining LazyCompoundVals in cases like this: CGRect r = CGRectMake(0, 0, 640, 480); CGRect r2 = r; CGRect r3 = r2; Previously we only made this optimization if the struct did not begin with an aggregate member, to make sure that we weren't picking up an LCV for the first field of the struct. But since LazyCompoundVals are typed, we can make that inference directly by comparing types. This is a pure optimization; the test changes are to guard against possible future regressions. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174211 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-31[analyzer] If a lazy binding is undefined, pretend that it's unknown instead.Jordan Rose
This is a hack to work around the fact that we don't track extents for our default bindings: CGPoint p; p.x = 0.0; p.y = 0.0; rectParam.origin = p; use(rectParam.size); // warning: uninitialized value in rectParam.size.width In this case, the default binding for 'p' gets copied into 'rectParam', because the 'origin' field is at offset 0 within CGRect. From then on, rectParam's old default binding (in this case a symbol) is lost. This patch silences the warning by pretending that lazy bindings are never made from uninitialized memory, but not only is that not true, the original default binding is still getting overwritten (see FIXME test cases). The long-term solution is tracked in <rdar://problem/12701038> PR14765 and <rdar://problem/12875012> git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174031 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-31[analyzer] Fix a bug in region store that lead to undefined value falseAnna Zaks
positives. The includeSuffix was only set on the first iteration through the function, resulting in invalid regions being produced by getLazyBinding (ex: zoomRegion.y). git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@174016 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-12Remove useless 'llvm::' qualifier from names like StringRef and others that areDmitri Gribenko
brought into 'clang' namespace by clang/Basic/LLVM.h git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@172323 91177308-0d34-0410-b5e6-96231b3b80d8
2013-01-09Do not model loads from complex types, since we don't accurately model the ↵Ted Kremenek
imaginary and real parts yet. Fixes false positive reported in <rdar://problem/12964481>. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@171987 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-20[analyzer] Add the pointer escaped callback.Anna Zaks
Instead of using several callbacks to identify the pointer escape event, checkers now can register for the checkPointerEscape. Converted the Malloc checker to use the new callback. SimpleStreamChecker will be converted next. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@170625 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-14Refactor dump methods to make RegionBindingsRef printable in the debugger.Ted Kremenek
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@170170 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-07Reduce conversions between Store <-> ImmutableMapRef in RegionStore.Ted Kremenek
This reduces canonicalization of ImmutableMaps. This reduces analysis time of one heavy Objective-C file by another 1%. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169630 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-07Add helper method to convert from a RegionStoreRefBindings to a Store.Ted Kremenek
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169622 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-07Further reduce analysis time by 0.2% on a heavy Objective-C example by ↵Ted Kremenek
avoiding over-eager canonicalization of clusters. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169586 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-07Unbreak the GCC (4.4 & other bot) builds from r169571.David Blaikie
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169581 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-07Change RegionStore to always use ImmutableMapRef for processing cluster ↵Ted Kremenek
bindings. This reduces analysis time by 1.2% on one test case (Objective-C), but also cleans up some of the code conceptually as well. We can possible just make RegionBindingsRef -> RegionBindings, but I wanted to stage things. After this, we should revisit Jordan's optimization of not canonicalizing the immutable AVL trees for the cluster bindings as well. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169571 91177308-0d34-0410-b5e6-96231b3b80d8
2012-12-06Revert "[analyzer] Aggressively cut back on the canonicalization in ↵Ted Kremenek
RegionStore." Jordan and I discussed this, and we are going to do this another way. git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@169538 91177308-0d34-0410-b5e6-96231b3b80d8