Now, instead of passing the reference to a shared_ptr, we pass the shared_ptr instead.
I've also removed the check if Z3 is present in CreateZ3ConstraintManager as this function already calls CreateZ3Solver that performs the exactly same check.
Differential Revision: https://reviews.llvm.org/D54976
llvm-svn: 353371
This patch moves the ConstraintSMT definition to the SMTConstraintManager header to make it easier to move the Z3 backend around.
We achieve this by not using shared_ptr anymore, as llvm::ImmutableSet doesn't seem to like it.
The solver specific exprs and sorts are cached in the Z3Solver object now and we move pointers to those objects around.
As a nice side-effect, SMTConstraintManager doesn't have to be a template anymore. Yay!
Differential Revision: https://reviews.llvm.org/D54975
llvm-svn: 353370
Memory region that correspond to a variable is identified by the variable's
declaration and, in case of local variables, the stack frame it belongs to.
The declaration needs to be canonical, otherwise we'd have two different
memory regions that correspond to the same variable.
Fix such bug for global variables with forward declarations and assert
that no other problems of this kind happen.
Differential Revision: https://reviews.llvm.org/D57619
llvm-svn: 353353
This reverts commit r341722.
The "postponed" mechanism turns out to be necessary in order to handle
situations when a symbolic region is only kept alive by implicit bindings
in the Store. Otherwise the region is never scanned by the Store's worklist
and the binding gets dropped despite being live, as demonstrated
by the newly added tests.
Differential Revision: https://reviews.llvm.org/D57554
llvm-svn: 353350
When a function takes the address of a field the analyzer will no longer
assume that the function will change other fields of the enclosing structs.
Differential Revision: https://reviews.llvm.org/D57230
llvm-svn: 352473
As noted in https://bugs.llvm.org/show_bug.cgi?id=36651, the specialization for
isPodLike<std::pair<...>> did not match the expectation of
std::is_trivially_copyable which makes the memcpy optimization invalid.
This patch renames the llvm::isPodLike trait into llvm::is_trivially_copyable.
Unfortunately std::is_trivially_copyable is not portable across compiler / STL
versions. So a portable version is provided too.
Note that the following specialization were invalid:
std::pair<T0, T1>
llvm::Optional<T>
Tests have been added to assert that former specialization are respected by the
standard usage of llvm::is_trivially_copyable, and that when a decent version
of std::is_trivially_copyable is available, llvm::is_trivially_copyable is
compared to std::is_trivially_copyable.
As of this patch, llvm::Optional is no longer considered trivially copyable,
even if T is. This is to be fixed in a later patch, as it has impact on a
long-running bug (see r347004)
Note that GCC warns about this UB, but this got silented by https://reviews.llvm.org/D50296.
Differential Revision: https://reviews.llvm.org/D54472
llvm-svn: 351701
to reflect the new license.
We understand that people may be surprised that we're moving the header
entirely to discuss the new license. We checked this carefully with the
Foundation's lawyer and we believe this is the correct approach.
Essentially, all code in the project is now made available by the LLVM
project under our new license, so you will see that the license headers
include that license only. Some of our contributors have contributed
code under our old license, and accordingly, we have retained a copy of
our old license notice in the top-level files in each project and
repository.
llvm-svn: 351636
Add a defensive check against an invalid destructor in the CFG.
Unions with fields with destructors have their own destructor implicitly
deleted. Due to a bug in the CFG we're still trying to evaluate them
at the end of the object's lifetime and crash because we are unable
to find the destructor's declaration.
rdar://problem/47362608
Differential Revision: https://reviews.llvm.org/D56899
llvm-svn: 351610
SymbolReaper now realizes that our liveness analysis isn't sharp enough
to discriminate between liveness of, say, variables and their fields.
Surprisingly, this didn't quite work before: having a variable live only
through Environment (eg., calling a C++ method on a local variable
as the last action ever performed on that variable) would not keep the
region value symbol of a field of that variable alive.
It would have been broken in the opposite direction as well, but both
Environment and RegionStore use the scanReachableSymbols mechanism for finding
live symbols regions within their values, and due to that they accidentally
end up marking the whole chain of super-regions as live when at least one
sub-region is known to be live.
It is now a direct responsibility of SymbolReaper to maintain this invariant,
and a unit test was added in order to make sure it stays that way.
Differential Revision: https://reviews.llvm.org/D56632
rdar://problem/46914108
llvm-svn: 351499
Summary:
https://reviews.llvm.org/D54862 removed the usages of `ASTContext&` from
within the `CXXMethodDecl::getThisType` method. Remove the parameter
altogether, as well as all usages of it. This does not result in any
functional change because the parameter was unused since
https://reviews.llvm.org/D54862.
Test Plan: check-clang
Reviewers: akyrtzi, mikael
Reviewed By: mikael
Subscribers: mehdi_amini, dexonsmith, cfe-commits
Differential Revision: https://reviews.llvm.org/D56509
llvm-svn: 350914
Several headers would fail to compile if other headers were not previously
included. The usual issue is that a class is forward declared, but the
full definition is needed. The requirement for the definition is use of
isa/dyn_cast or calling functions of pointer-packed data types such as
DenseMap or PointerIntPair. Add missing includes to these headers.
SVals.h required an out-of-line method definition in the .cpp file to avoid
circular inclusion of headers with BasicValueFactory.h
llvm-svn: 350913
We need to be able to emit the diagnostic at PreImplicitCall,
and the patch implements this functionality.
However, for now the need for emitting such diagnostics is not all that great:
it is only necessary to not crash when emitting a false positive due to an
unrelated issue of having dead symbol collection not working properly.
Coming up with a non-false-positive test seems impossible with the current
set of checkers, though it is likely to be needed for good things as well
in the future.
Differential Revision: https://reviews.llvm.org/D56042
rdar://problem/46911462
llvm-svn: 350907
Make sure all checks for attributes go through a centralized function,
which checks whether attribute handling is enabled, and performs
validation. The type of the attribute is returned.
Sadly, metaprogramming is required as attributes have no sensible static
getters.
Differential Revision: https://reviews.llvm.org/D56222
llvm-svn: 350862
Summary: The LocationE parameter of evalStore is documented as "The location expression that is stored to". When storing from an increment / decrement operator this was not satisfied. In user code this causes an inconsistency between the SVal and Stmt parameters of checkLocation.
Reviewers: NoQ, dcoughlin, george.karpenkov
Reviewed By: NoQ
Subscribers: xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, cfe-commits
Differential Revision: https://reviews.llvm.org/D55701
llvm-svn: 350528
Previously, argument effects were stored in a method variable, which was
effectively global.
The global state was reset at each (hopefully) entrance point to the
summary construction,
and every function could modify it.
Differential Revision: https://reviews.llvm.org/D56036
llvm-svn: 350057
This patch is a different approach to landing the reverted r349701.
It is expected to have the same object (memory region) treated as if it has
different types in different program points. The correct behavior for
RegionStore when an object is stored as an object of type T1 but loaded as
an object of type T2 is to store the object as if it has type T1 but cast it
to T2 during load.
Note that the cast here is some sort of a "reinterpret_cast" (even in C). For
instance, if you store an integer and load a float, you won't get your integer
represented as a float; instead, you will get garbage.
Admit that we cannot perform the cast and return an unknown value.
Differential Revision: https://reviews.llvm.org/D55875
rdar://problem/45062567
llvm-svn: 349984
If it ends with "Retain" like CFRetain and returns a CFTypeRef like CFRetain,
then it is not necessarily a CFRetain. But it is indeed true that these two
return something retained.
Differential Revision: https://reviews.llvm.org/D55907
rdar://problem/39390714
llvm-svn: 349862
This adds anchors to all of the documented checks so that you can directly link to a check by a stable name. This is useful because the SARIF file format has a field for specifying a URI to documentation for a rule and some viewers, like CodeSonar, make use of this information. These links are then exposed through the SARIF exporter.
llvm-svn: 349812
This reverts commit r349701.
The patch was incorrect. The whole point of CastRetrievedVal()
is to handle the case in which the type from which the cast is made
(i.e., the "type" of value `V`) has nothing to do with the type of
the region it was loaded from (i.e., `R->getValueType()`).
Differential Revision: https://reviews.llvm.org/D55875
rdar://problem/45062567
llvm-svn: 349798
It is expected to have the same object (memory region) treated as if it has
different types in different program points. The correct behavior for
RegionStore when an object is stored as an object of type T1 but loaded as
an object of type T2 is to store the object as if it has type T1 but cast it
to T2 during load.
Note that the cast here is some sort of a "reinterpret_cast" (even in C). For
instance, if you store a float and load an integer, you won't have your float
rounded to an integer; instead, you will have garbage.
Admit that we cannot perform the cast as long as types we're dealing with are
non-trivial (neither integers, nor pointers).
Of course, if the cast is not necessary (eg, T1 == T2), we can still load the
value just fine.
Differential Revision: https://reviews.llvm.org/D55875
rdar://problem/45062567
llvm-svn: 349701
Static Analyzer processes the program function-by-function, sometimes diving
into other functions ("inlining" them). When an object is returned from an
inlined function, Return Value Optimization is modeled, and the returned object
is constructed at its return location directly.
When an object is returned from the function from which the analysis has started
(the top stack frame of the analysis), the return location is unknown. Model it
with a SymbolicRegion based on a conjured symbol that is specifically tagged for
that purpose, because this is generally the correct way to symbolicate
unknown locations in Static Analyzer.
Fixes leak false positives when an object is returned from top frame in C++17:
objects that are put into a SymbolicRegion-based memory region automatically
"escape" and no longer get reported as leaks. This only applies to C++17 return
values with destructors, because it produces a redundant CXXBindTemporaryExpr
in the call site, which confuses our liveness analysis. The actual fix
for liveness analysis is still pending, but it is no longer causing problems.
Additionally, re-enable temporary destructor tests in C++17.
Differential Revision: https://reviews.llvm.org/D55804
rdar://problem/46217550
llvm-svn: 349696
ClangCheckerRegistry is a very non-obvious, poorly documented, weird concept.
It derives from CheckerRegistry, and is placed in lib/StaticAnalyzer/Frontend,
whereas it's base is located in lib/StaticAnalyzer/Core. It was, from what I can
imagine, used to circumvent the problem that the registry functions of the
checkers are located in the clangStaticAnalyzerCheckers library, but that
library depends on clangStaticAnalyzerCore. However, clangStaticAnalyzerFrontend
depends on both of those libraries.
One can make the observation however, that CheckerRegistry has no place in Core,
it isn't used there at all! The only place where it is used is Frontend, which
is where it ultimately belongs.
This move implies that since
include/clang/StaticAnalyzer/Checkers/ClangCheckers.h only contained a single function:
class CheckerRegistry;
void registerBuiltinCheckers(CheckerRegistry ®istry);
it had to re purposed, as CheckerRegistry is no longer available to
clangStaticAnalyzerCheckers. It was renamed to BuiltinCheckerRegistration.h,
which actually describes it a lot better -- it does not contain the registration
functions for checkers, but only those generated by the tblgen files.
Differential Revision: https://reviews.llvm.org/D54436
llvm-svn: 349275
Renaming collectCheckers to getEnabledCheckers
Changing the functionality to acquire all enabled checkers, rather then collect
checkers for a specific CheckerOptInfo (for example, collecting all checkers for
{ "core", true }, which meant enabling all checkers from the core package, which
was an unnecessary complication).
Removing CheckerOptInfo, instead of storing whether the option was claimed via a
field, we handle errors immediately, as getEnabledCheckers can now access a
DiagnosticsEngine. Realize that the remaining information it stored is directly
accessible through AnalyzerOptions.CheckerControlList.
Fix a test with -analyzer-disable-checker -verify accidentally left in.
llvm-svn: 349274
Right now they report to have one parameter with null decl,
because initializing an ArrayRef of pointers with a nullptr
yields an ArrayRef to an array of one null pointer.
Fixes a crash in the OSObject section of RetainCountChecker.
Differential Revision: https://reviews.llvm.org/D55671
llvm-svn: 349229
Functional changes include:
* The run.files property is now an array instead of a mapping.
* fileLocation objects now have a fileIndex property specifying the array index into run.files.
* The resource.rules property is now an array instead of a mapping.
* The result object was given a ruleIndex property that is an index into the resource.rules array.
* rule objects now have their "id" field filled out in addition to the name field.
* Updated the schema and spec version numbers to 11-28.
llvm-svn: 349188
Allow enabling and disabling tracking of ObjC/CF objects
separately from tracking of OS objects.
Differential Revision: https://reviews.llvm.org/D55400
llvm-svn: 348638
Summary:
With a new switch we may be able to print to stderr if a new TU is being loaded
during CTU. This is very important for higher level scripts (like CodeChecker)
to be able to parse this output so they can create e.g. a zip file in case of
a Clang crash which contains all the related TU files.
Reviewers: xazax.hun, Szelethus, a_sidorin, george.karpenkov
Subscribers: whisperity, baloghadamsoftware, szepet, rnkovacs, a.sidorin, mikhail.ramalho, donat.nagy, dkrupp,
Differential Revision: https://reviews.llvm.org/D55135
llvm-svn: 348594
If an iterator is represented by a derived C++ class but its comparison operator
is for its base the iterator checkers cannot recognize the iterators compared.
This results in false positives in very straightforward cases (range error when
dereferencing an iterator after disclosing that it is equal to the past-the-end
iterator).
To overcome this problem we always use the region of the topmost base class for
iterators stored in a region. A new method called getMostDerivedObjectRegion()
was added to the MemRegion class to get this region.
Differential Revision: https://reviews.llvm.org/D54466
llvm-svn: 348244
This continues the work that was started in r342313, which now gets applied to
object-under-construction tracking in C++. Makes it possible to debug
temporaries by dumping exploded graphs again.
Differential Revision: https://reviews.llvm.org/D54459
llvm-svn: 348200
It seems the two failing tests can be simply fixed after r348037
Fix 3 cases in Analysis/builtin-functions.cpp
Delete the bad CodeGen/builtin-constant-p.c for now
llvm-svn: 348053
Kept the "indirect_builtin_constant_p" test case in test/SemaCXX/constant-expression-cxx1y.cpp
while we are investigating why the following snippet fails:
extern char extern_var;
struct { int a; } a = {__builtin_constant_p(extern_var)};
llvm-svn: 348039
In earlier patches regarding AnalyzerOptions, a lot of effort went into
gathering all config options, and changing the interface so that potential
misuse can be eliminited.
Up until this point, AnalyzerOptions only evaluated an option when it was
querried. For example, if we had a "-no-false-positives" flag, AnalyzerOptions
would store an Optional field for it that would be None up until somewhere in
the code until the flag's getter function is called.
However, now that we're confident that we've gathered all configs, we can
evaluate off of them before analysis, so we can emit a error on invalid input
even if that prticular flag will not matter in that particular run of the
analyzer. Another very big benefit of this is that debug.ConfigDumper will now
show the value of all configs every single time.
Also, almost all options related class have a similar interface, so uniformity
is also a benefit.
The implementation for errors on invalid input will be commited shorty.
Differential Revision: https://reviews.llvm.org/D53692
llvm-svn: 348031
From what I can see, this should be the last patch needed to replicate macro
argument expansions.
Differential Revision: https://reviews.llvm.org/D52988
llvm-svn: 348025
During the review of D41938 a condition check with an early exit accidentally
slipped into a branch, leaving the other branch unprotected. This may result in
an assertion later on. This hotfix moves this contition check outside of the
branch.
Differential Revision: https://reviews.llvm.org/D55051
llvm-svn: 347981
It's an old bug that consists in stale references to symbols remaining in the
GDM if they disappear from other program state sections as a result of any
operation that isn't the actual dead symbol collection. The most common example
here is:
FILE *fp = fopen("myfile.txt", "w");
fp = 0; // leak of file descriptor
In this example the leak were not detected previously because the symbol
disappears from the public part of the program state due to evaluating
the assignment. For that reason the checker never receives a notification
that the symbol is dead, and never reports a leak.
This patch not only causes leak false negatives, but also a number of other
problems, including false positives on some checkers.
What's worse, even though the program state contains a finite number of symbols,
the set of symbols that dies is potentially infinite. This means that is
impossible to compute the set of all dead symbols to pass off to the checkers
for cleaning up their part of the GDM.
No longer compute the dead set at all. Disallow iterating over dead symbols.
Disallow querying if any symbols are dead. Remove the API for marking symbols
as dead, as it is no longer necessary. Update checkers accordingly.
Differential Revision: https://reviews.llvm.org/D18860
llvm-svn: 347953
The "free" call frees the object immediately, ignoring the reference count.
Sadly, it is actually used in a few places, so we need to model it.
Differential Revision: https://reviews.llvm.org/D55092
llvm-svn: 347950
Summary: Left only the constructors that are actually required, and marked the move constructors as deleted. They are not used anymore and we were never sure they've actually worked correctly.
Reviewers: george.karpenkov, NoQ
Reviewed By: george.karpenkov
Subscribers: xazax.hun, baloghadamsoftware, szepet, a.sidorin, Szelethus, donat.nagy, dkrupp
Differential Revision: https://reviews.llvm.org/D54974
llvm-svn: 347777
This was reverted in r347656 due to me thinking it caused a miscompile of
Chromium. Turns out it was the Chromium code that was broken.
llvm-svn: 347756
This caused a miscompile in Chrome (see crbug.com/908372) that's
illustrated by this small reduction:
static bool f(int *a, int *b) {
return !__builtin_constant_p(b - a) || (!(b - a));
}
int arr[] = {1,2,3};
bool g() {
return f(arr, arr + 3);
}
$ clang -O2 -S -emit-llvm a.cc -o -
g() should return true, but after r347417 it became false for some reason.
This also reverts the follow-up commits.
r347417:
> Re-Reinstate 347294 with a fix for the failures.
>
> Don't try to emit a scalar expression for a non-scalar argument to
> __builtin_constant_p().
>
> Third time's a charm!
r347446:
> The result of is.constant() is unsigned.
r347480:
> A __builtin_constant_p() returns 0 with a function type.
r347512:
> isEvaluatable() implies a constant context.
>
> Assume that we're in a constant context if we're asking if the expression can
> be compiled into a constant initializer. This fixes the issue where a
> __builtin_constant_p() in a compound literal was diagnosed as not being
> constant, even though it's always possible to convert the builtin into a
> constant.
r347531:
> A "constexpr" is evaluated in a constant context. Make sure this is reflected
> if a __builtin_constant_p() is a part of a constexpr.
llvm-svn: 347656
Summary:
A __builtin_constant_p may end up with a constant after inlining. Use
the is.constant intrinsic if it's a variable that's in a context where
it may resolve to a constant, e.g., an argument to a function after
inlining.
Reviewers: rsmith, shafik
Subscribers: jfb, kristina, cfe-commits, nickdesaulniers, jyknight
Differential Revision: https://reviews.llvm.org/D54355
llvm-svn: 347294
CheckerOptInfo feels very much out of place in CheckerRegistration.cpp, so I
moved it to CheckerRegistry.h.
Differential Revision: https://reviews.llvm.org/D54397
llvm-svn: 347157
With z3-4.8.1:
../tools/clang/lib/StaticAnalyzer/Core/Z3ConstraintManager.cpp:49:40: error:
'Z3_get_error_msg_ex' was not declared in this scope
../tools/clang/lib/StaticAnalyzer/Core/Z3ConstraintManager.cpp:49:40: note:
suggested alternative: 'Z3_get_error_msg'
Formerly used Z3_get_error_msg_ex() as one could find in z3-4.7.1 states:
"Retained function name for backwards compatibility within v4.1"
And it is implemented only as a forwarding call:
return Z3_get_error_msg(c, err);
Differential Revision: https://reviews.llvm.org/D54391
llvm-svn: 346635
Summary:
Compound literals, enums, file-scoped arrays, etc. require their
initializers and size specifiers to be constant. Wrap the initializer
expressions in a ConstantExpr so that we can easily check for this later
on.
Reviewers: rsmith, shafik
Reviewed By: rsmith
Subscribers: cfe-commits, jyknight, nickdesaulniers
Differential Revision: https://reviews.llvm.org/D53921
llvm-svn: 346455
One of the reasons why AnalyzerOptions is so chaotic is that options can be
retrieved from the command line whenever and wherever. This allowed for some
options to be forgotten for a looooooong time. Have you ever heard of
"region-store-small-struct-limit"? In order to prevent this in the future, I'm
proposing to restrict AnalyzerOptions' interface so that only checker options
can be retrieved without special getters. I would like to make every option be
accessible only through a getter, but checkers from plugins are a thing, so I'll
have to figure something out for that.
This also forces developers who'd like to add a new option to register it
properly in the .def file.
This is done by
* making the third checker pointer parameter non-optional, and checked by an
assert to be non-null.
* I added new, but private non-checkers option initializers, meant only for
internal use,
* Renamed these methods accordingly (mind the consistent name for once with
getBooleanOption!):
- getOptionAsString -> getCheckerStringOption,
- getOptionAsInteger -> getCheckerIntegerOption
* The 3 functions meant for initializing data members (with the not very
descriptive getBooleanOption, getOptionAsString and getOptionAsUInt names)
were renamed to be overloads of the getAndInitOption function name.
* All options were in some way retrieved via getCheckerOption. I removed it, and
moved the logic to getStringOption and getCheckerStringOption. This did cause
some code duplication, but that's the only way I could do it, now that checker
and non-checker options are separated. Note that the non-checker version
inserts the new option to the ConfigTable with the default value, but the
checker version only attempts to find already existing entries. This is how
it always worked, but this is clunky and I might end reworking that too, so we
can eventually get a ConfigTable that contains the entire configuration of the
analyzer.
Differential Revision: https://reviews.llvm.org/D53483
llvm-svn: 346113
Windows buildbots break with the previous commit '[analyzer][PlistMacroExpansion]
Part 2.: Retrieving the macro name and primitive expansion'. This patch attempts
to solve this issue.
llvm-svn: 346112
This patch adds a couple new functions to acquire the macro's name, and also
expands it, although it doesn't expand the arguments, as seen from the test files
Differential Revision: https://reviews.llvm.org/D52794
llvm-svn: 346095
This exposes a (known) CodeGen bug: it can't cope with emitting lvalue
expressions that denote non-odr-used but usable-in-constant-expression
variables. See PR39528 for a testcase.
Reverted for now until that issue can be fixed.
llvm-svn: 346065
I'm in the process of refactoring AnalyzerOptions. The main motivation behind
here is to emit warnings if an invalid -analyzer-config option is given from the
command line, and be able to list them all.
In this patch, I'm moving all analyzer options to a def file, and move 2 enums
to global namespace.
Differential Revision: https://reviews.llvm.org/D53277
llvm-svn: 345986
I'm in the process of refactoring AnalyzerOptions. The main motivation behind
here is to emit warnings if an invalid -analyzer-config option is given from
the command line, and be able to list them all.
In this patch, I found some flags that should've been used as checker options,
or have absolutely no mention of in AnalyzerOptions, or are nonexistent.
- NonLocalizedStringChecker now uses its "AggressiveReport" flag as a checker
option
- lib/StaticAnalyzer/Frontend/ModelInjector.cpp now accesses the "model-path"
option through a getter in AnalyzerOptions
- -analyzer-config path-diagnostics-alternate=false is not a thing, I removed it,
- lib/StaticAnalyzer/Checkers/AllocationDiagnostics.cpp and
lib/StaticAnalyzer/Checkers/AllocationDiagnostics.h are weird, they actually
only contain an option getter. I deleted them, and fixed RetainCountChecker
to get it's "leak-diagnostics-reference-allocation" option as a checker option,
- "region-store-small-struct-limit" has a proper getter now.
Differential Revision: https://reviews.llvm.org/D53276
llvm-svn: 345985
This patch should not introduce any behavior changes. It consists of
mostly one of two changes:
1. Replacing fall through comments with the LLVM_FALLTHROUGH macro
2. Inserting 'break' before falling through into a case block consisting
of only 'break'.
We were already using this warning with GCC, but its warning behaves
slightly differently. In this patch, the following differences are
relevant:
1. GCC recognizes comments that say "fall through" as annotations, clang
doesn't
2. GCC doesn't warn on "case N: foo(); default: break;", clang does
3. GCC doesn't warn when the case contains a switch, but falls through
the outer case.
I will enable the warning separately in a follow-up patch so that it can
be cleanly reverted if necessary.
Reviewers: alexfh, rsmith, lattner, rtrieu, EricWF, bollu
Differential Revision: https://reviews.llvm.org/D53950
llvm-svn: 345882
SARIF allows you to export descriptions about rules that are present in the SARIF log. Expose the help text table generated into Checkers.inc as the rule's "full description" and export all of the rules present in the analysis output. This information is useful for analysis result viewers like CodeSonar.
llvm-svn: 345874
This removes the Step property (which can be calculated by consumers trivially), and updates the schema and version numbers accordingly.
llvm-svn: 345823
Trusting summaries of inlined code would require a more thorough work,
as the current approach was causing too many false positives, as the new
example in test. The culprit lies in the fact that we currently escape
all variables written into a field (but not passed off to unknown
functions!), which can result in inconsistent behavior.
rdar://45655344
Differential Revision: https://reviews.llvm.org/D53902
llvm-svn: 345746
This is the first part of the implementation of the inclusion of macro
expansions into the plist output. It adds a new flag that adds a new
"macro_expansions" entry to each report that has PathDiagnosticPieces that were
expanded from a macro. While there's an entry for each macro expansion, both
the name of the macro and what it expands to is missing, and will be implemented
in followup patches.
Differential Revision: https://reviews.llvm.org/D52742
llvm-svn: 345724
A ConstantExpr class represents a full expression that's in a context where a
constant expression is required. This class reflects the path the evaluator
took to reach the expression rather than the syntactic context in which the
expression occurs.
In the future, the class will be expanded to cache the result of the evaluated
expression so that it's not needlessly re-evaluated
Reviewed By: rsmith
Differential Revision: https://reviews.llvm.org/D53475
llvm-svn: 345692
This allows users to specify SARIF (https://github.com/oasis-tcs/sarif-spec) as the output from the clang static analyzer so that the results can be read in by other tools, such as extensions to Visual Studio and VSCode, as well as static analyzers like CodeSonar.
llvm-svn: 345628
nullptr_t does not access memory.
We now reuse CK_NullToPointer to represent a conversion from a glvalue
of type nullptr_t to a prvalue of nullptr_t where necessary.
llvm-svn: 345562
This has been a long time coming. Note the usage of AnalyzerOptions: I'll need
it for D52742, and added it in rC343620. The main motivation for this was that
I'll need to add yet another parameter to every single function, and some
functions would reach their 10th parameter with that change.
llvm-svn: 345531
Nodes which have only one predecessor and only one successor can not
always be hidden, even if all states are the same.
An additional condition is needed: the predecessor may have only one successor.
This can be seen on this example:
```
A
/ \
B C
\ /
D
```
Nodes B and C can not be hidden even if all nodes in the graph have the
same state.
Differential Revision: https://reviews.llvm.org/D53735
llvm-svn: 345341
Previously, OSDynamicCast was modeled as an identity.
This is not correct: the output of OSDynamicCast may be zero even if the
input was not zero (if the class is not of desired type), and thus the
modeling led to false positives.
Instead, we are doing eager state split:
in one branch, the returned value is identical to the input parameter,
and in the other branch, the returned value is zero.
This patch required a substantial refactoring of canEval infrastructure,
as now it can return different function summaries, and not just true/false.
rdar://45497400
Differential Revision: https://reviews.llvm.org/D53624
llvm-svn: 345338
Summary:
This patch moves the last method in `Z3ConstraintManager` to `SMTConstraintManager`: `canReasonAbout()`.
The `canReasonAbout()` method checks if a given `SVal` can be encoded in SMT. I've added a new method to the SMT API to return true if a solver can encode floating-point arithmetics and it was enough to make `canReasonAbout()` solver independent.
As an annoying side-effect, `Z3ConstraintManager` is pretty empty now and only (1) creates the Z3 solver object by calling `CreateZ3Solver()` and (2) instantiates `SMTConstraintManager`. Maybe we can get rid of this class altogether in the future: a `CreateSMTConstraintManager()` method that does (1) and (2) and returns the constraint manager object?
Reviewers: george.karpenkov, NoQ
Reviewed By: george.karpenkov
Subscribers: mehdi_amini, xazax.hun, szepet, a.sidorin, dexonsmith, Szelethus, donat.nagy, dkrupp
Differential Revision: https://reviews.llvm.org/D53694
llvm-svn: 345284
Summary:
Getting an `APSInt` from the model always returned an unsigned integer because of the unused parameter.
This was not breaking any test case because no code relies on the actual value of the integer returned here, but rather it is only used to check if a symbol has more than one solution in `getSymVal`.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin, Szelethus, donat.nagy, dkrupp
Differential Revision: https://reviews.llvm.org/D53637
llvm-svn: 345283
trackNullOrUndefValue is a long and confusing name,
and it does not actually reflect what the function is doing.
Give a function a new name, with a relatively clear semantics.
Also remove some dead code.
Differential Revision: https://reviews.llvm.org/D52758
llvm-svn: 345064
This patch is a part of https://reviews.llvm.org/D48456 in an attempt to split
the casting logic up into smaller patches. This contains the code for casting
from fixed point types to boolean types.
Differential Revision: https://reviews.llvm.org/D53308
llvm-svn: 345063
I'm in the process of refactoring AnalyzerOptions. The main motivation behind
here is to emit warnings if an invalid -analyzer-config option is given from the
command line, and be able to list them all.
This first NFC patch contains small modifications to make AnalyzerOptions.cpp a
little more consistent.
Differential Revision: https://reviews.llvm.org/D53274
llvm-svn: 344870
The GDMIndex functions return a pointer that's used as a key for looking up
data, but addresses of local statics defined in header files aren't the same
across shared library boundaries and the result is that analyzer plugins
can't access this data.
Event types are uniqued by using the addresses of a local static defined
in a header files, but it isn't the same across shared library boundaries
and plugins can't currently handle ImplicitNullDerefEvents.
Patches by Joe Ranieri!
Differential Revision: https://reviews.llvm.org/D52905
Differential Revision: https://reviews.llvm.org/D52906
llvm-svn: 344823
In C++17, when class C has large alignment value, a special case of
overload resolution rule kicks in for expression new C that causes the aligned
version of operator new() to be called. The aligned new has two arguments:
size and alignment. However, the new-expression has only one "argument":
the construct-expression for C(). This causes a false positive in
core.CallAndMessage's check for matching number of arguments and number
of parameters.
Update CXXAllocatorCall, which is a CallEvent sub-class for operator new calls
within new-expressions, so that the number of arguments always matched
the number of parameters.
rdar://problem/44738501
Differential Revision: https://reviews.llvm.org/D52957
llvm-svn: 344539
This patch is a part of https://reviews.llvm.org/D48456 in an attempt to
split them up. This contains the code for casting between fixed point types
and other fixed point types.
The method for converting between fixed point types is based off the convert()
method in APFixedPoint.
Differential Revision: https://reviews.llvm.org/D50616
llvm-svn: 344530
Summary:
Enhanced support for Z3 in the cmake configuration of clang; now it is possible to specify any arbitrary Z3 install prefix (CLANG_ANALYZER_Z3_PREFIX) to cmake with lib (or bin) and include folders. Before the patch only in cmake default locations
were searched (https://cmake.org/cmake/help/v3.4/command/find_path.html).
Specifying any CLANG_ANALYZER_Z3_PREFIX will force also CLANG_ANALYZER_BUILD_Z3 to ON.
Removed also Z3 4.5 version requirement since it was not checked, and now Clang works with Z3 4.7
Reviewers: NoQ, george.karpenkov, mikhail.ramalho
Reviewed By: george.karpenkov
Subscribers: rnkovacs, NoQ, esteffin, george.karpenkov, delcypher, ddcc, mgorny, xazax.hun, szepet, a.sidorin, Szelethus
Tags: #clang
Differential Revision: https://reviews.llvm.org/D50818
llvm-svn: 344464
Doesn't do much despite sounding quite bad, but fixes an exotic test case where
liveness of a nonloc::LocAsInteger array index is now evaluated correctly.
Differential Revision: https://reviews.llvm.org/D52667
llvm-svn: 343631
I intend to add a new flag macro-expnasions-as-events, and unfortunately
I'll only be able to convert the macro piece into an event one once I'm
about to emit it, due to the lack of an avaible Preprocessor object in
the BugReporter.
Differential Revision: https://reviews.llvm.org/D52787
llvm-svn: 343620
Summary:
Several improvements in preparation for the new backends.
Refactoring:
- Removed duplicated methods `fromBoolean`, `fromAPSInt`, `fromInt` and `fromAPFloat`. The methods `mkBoolean`, `mkBitvector` and `mkFloat` are now used instead.
- The names of the functions that convert BVs to FPs were swapped (`mkSBVtoFP`, `mkUBVtoFP`, `mkFPtoSBV`, `mkFPtoUBV`).
- Added a couple of comments in function calls.
Crosscheck encoding:
- Changed how constraints are encoded in the refutation manager so it doesn't start with (false OR ...). This change introduces one duplicated line (see file `BugReporterVisitors.cpp`, the `SMTConv::getRangeExpr is called twice, so I can remove this change if the duplication is a problem.
Reviewers: george.karpenkov, NoQ
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin, Szelethus
Differential Revision: https://reviews.llvm.org/D52365
llvm-svn: 343581
This is patch is a preparation for the proposed inclusion of macro expansions in the plist output.
Differential Revision: https://reviews.llvm.org/D52735
llvm-svn: 343511
Dumping graphs instead of opening them is often very useful,
e.g. for transfer or converting to SVG.
Basic sanity check for generated exploded graphs.
Differential Revision: https://reviews.llvm.org/D52637
llvm-svn: 343352
Commit r340984 causes a crash when a pointer to a completely unrelated type
UnrelatedT (eg., opaque struct pattern) is being casted from base class BaseT to
derived class DerivedT, which results in an ill-formed region
Derived{SymRegion{$<UnrelatedT x>}, DerivedT}.
Differential Revision: https://reviews.llvm.org/D52189
llvm-svn: 343051
Combine the two constructor overrides into a single ArrayRef constructor
to allow easier brace initializations and simplify how the respective field
is used internally.
Differential Revision: https://reviews.llvm.org/D51390
llvm-svn: 343037
When a checker maintains a program state trait that isn't a simple list/set/map, but is a combination of multiple lists/sets/maps (eg., a multimap - which may be implemented as a map from something to set of something), ProgramStateManager only contains the factory for the trait itself. All auxiliary lists/sets/maps need a factory to be provided by the checker, which is annoying.
So far two checkers wanted a multimap, and both decided to trick the
ProgramStateManager into keeping the auxiliary factory within itself
by pretending that it's some sort of trait they're interested in,
but then never using this trait but only using the factory.
Make this trick legal. Define a convenient macro.
One thing that becomes apparent once all pieces are put together is that
these two checkers are in fact using the same factory, because the type that
identifies it, ImmutableMap<const MemRegion *, ImmutableSet<SymbolRef>>,
is the same. This situation is different from two checkers registering similar
primitive traits.
Differential Revision: https://reviews.llvm.org/D51388
llvm-svn: 343035
This patch is a band-aid. A proper solution would be too change
trackNullOrUndefValue to only try to dereference the pointer when it is
relevant to the problem.
Differential Revision: https://reviews.llvm.org/D52435
llvm-svn: 342920
If the non-sink report is generated at the exit node, it will be
suppressed by the current functionality in isInevitablySinking, as it
only checks the successors of the block, but not the block itself.
The bug shows up in RetainCountChecker checks.
Differential Revision: https://reviews.llvm.org/D52284
llvm-svn: 342766
Fixes a number of issues:
- Global variables are not used for communication
- Trait should be defined on a graph, not on a node
- Defining the trait on a graph allows us to use a correct allocator,
no longer crashing while printing trimmed graphs
Differential Revision: https://reviews.llvm.org/D52183
llvm-svn: 342413
Those are not created in the allocator.
Since they are created fairly rarely, a counter overhead should not
affect the memory consumption.
Differential Revision: https://reviews.llvm.org/D51827
llvm-svn: 342314
The "derived" symbols indicate children fields of a larger symbol.
As parents do not have pointers to their children, the garbage
collection algorithm the analyzer currently uses adds such symbols into
a "postponed" category, and then keeps running through the worklist
until the fixed point is reached.
The current patch rectifies that by instead using a helper map which
stores pointers from parents to children, so that no fixed point
calculation is necessary.
The current patch yields ~5% improvement in running time on sqlite.
Differential Revision: https://reviews.llvm.org/D51397
llvm-svn: 341722
A node is considered to be trivial if it only has one successor, one
predecessor, and a state equal to the predecessor.
Can drastically (> 2x) reduce the size of the generated exploded
graph.
Differential Revision: https://reviews.llvm.org/D51665
llvm-svn: 341616
Ubigraph project has been dead since about 2008, and to the best of my
knowledge, no one was using it.
Previously, I wasn't able to launch the existing binary at all.
Differential Revision: https://reviews.llvm.org/D51655
llvm-svn: 341601
Introduce a new MemRegion sub-class, CXXDerivedObjectRegion, which is
the opposite of CXXBaseObjectRegion, to represent such casts. Such region is
a bit weird because it is by design bigger than its super-region.
But it's not harmful when it is put on top of a SymbolicRegion
that has unknown extent anyway.
Offset computation for CXXDerivedObjectRegion and proper modeling of casts
still remains to be implemented.
Differential Revision: https://reviews.llvm.org/D51191
llvm-svn: 340984
The analyzer doesn't make use of them anyway and they seem to have
pretty weird AST from time to time, so let's just skip them for now.
Fixes a crash reported as pr37769.
Differential Revision: https://reviews.llvm.org/D50855
llvm-svn: 340977
By making sure the returned value from getKnownSVal is consistent with
the value used inside expression engine.
PR38427
Differential Revision: https://reviews.llvm.org/D51252
llvm-svn: 340965
Summary:
With this patch, the SMT backend is almost completely detached from the CSA.
Unfortunate consequence is that we missed the `ConditionTruthVal` from the CSA and had to use `Optional<bool>`.
The Z3 solver implementation is still in the same file as the `Z3ConstraintManager`, in `lib/StaticAnalyzer/Core/Z3ConstraintManager.cpp` though, but except for that, the SMT API can be moved to anywhere in the codebase.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin, Szelethus
Differential Revision: https://reviews.llvm.org/D50772
llvm-svn: 340534
Summary:
By making SMTConstraintManager a template and passing the SMT constraint type and expr, we can further move code from the Z3ConstraintManager class to the generic SMT constraint Manager.
Now, each SMT specific constraint manager only needs to implement the method `bool canReasonAbout(SVal X) const`.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: mgorny, xazax.hun, szepet, a.sidorin, Szelethus
Differential Revision: https://reviews.llvm.org/D50770
llvm-svn: 340533
Summary: There is no reason to have a base class for a context anymore as each SMT object carries a reference to the specific solver context.
Reviewers: NoQ, george.karpenkov, hiraditya
Reviewed By: hiraditya
Subscribers: hiraditya, xazax.hun, szepet, a.sidorin, Szelethus
Differential Revision: https://reviews.llvm.org/D50768
llvm-svn: 340532
Tracking those can help to provide much better diagnostics in many cases.
In general, most of the visitor machinery should be refactored to allow
tracking the origin of arbitrary values.
rdar://36039765
Differential Revision: https://reviews.llvm.org/D51131
llvm-svn: 340475
Summary:
`CallDecription` can only handle function for the time being. If we want to match c++ method, we can only use method name to match and can't improve the matching accuracy through the qualifiers.
This patch add the support for `QualifiedName` matching to improve the matching accuracy.
Reviewers: xazax.hun, NoQ, george.karpenkov, rnkovacs
Reviewed By: xazax.hun, NoQ, rnkovacs
Subscribers: Szelethus, szepet, rnkovacs, a.sidorin, mikhail.ramalho, cfe-commits, MTC
Differential Revision: https://reviews.llvm.org/D48027
llvm-svn: 340407
Turns out it can't be removed from the analyzer since it relies on CallEvent.
Moving to staticAnalyzer/core
Differential Revision: https://reviews.llvm.org/D51023
llvm-svn: 340247
Specifically, AttributedType now tracks a regular attr::Kind rather than
having its own parallel Kind enumeration, and AttributedTypeLoc now
holds an Attr* instead of holding an ad-hoc collection of Attr fields.
Differential Revision: https://reviews.llvm.org/D50526
This reinstates r339623, reverted in r339638, with a fix to not fail
template instantiation if we instantiate a QualType with no associated
type source information and we encounter an AttributedType.
llvm-svn: 340215
Once CFG-side support for argument construction contexts landed in r338436,
the analyzer could make use of them to evaluate argument constructors properly.
When evaluated as calls, constructors of arguments now use the variable region
of the parameter as their target. The corresponding stack frame does not yet
exist when the parameter is constructed, and this stack frame is created
eagerly.
Construction of functions whose body is unavailable and of virtual functions
is not yet supported. Part of the reason is the analyzer doesn't consistently
use canonical declarations o identify the function in these cases, and every
re-declaration or potential override comes with its own set of parameter
declarations. Also it is less important because if the function is not
inlined, there's usually no benefit in inlining the argument constructor.
Differential Revision: https://reviews.llvm.org/D49443
llvm-svn: 339745
This breaks compiling atlwin.h in Chromium. I'm sure the code is invalid
in some way, but we put a lot of work into accepting it, and I'm sure
rejecting it was not an intended consequence of this refactoring. :)
llvm-svn: 339638
Specifically, AttributedType now tracks a regular attr::Kind rather than
having its own parallel Kind enumeration, and AttributedTypeLoc now
holds an Attr* instead of holding an ad-hoc collection of Attr fields.
Differential Revision: https://reviews.llvm.org/D50526
llvm-svn: 339623
Lambdas can affect static locals even without an explicit capture.
rdar://39537031
Differential Revision: https://reviews.llvm.org/D50368
llvm-svn: 339459
Summary:
The loop-widening code processes c++ methods looking for `this` pointers. In
the case of static methods (which do not have `this` pointers), an assertion
was triggering. This patch avoids trying to process `this` pointers for
static methods, and thus avoids triggering the assertion .
Reviewers: dcoughlin, george.karpenkov, NoQ
Reviewed By: NoQ
Subscribers: NoQ, xazax.hun, szepet, a.sidorin, mikhail.ramalho, cfe-commits
Differential Revision: https://reviews.llvm.org/D50408
llvm-svn: 339201
Some checkers require ASTContext. Having it in the constructor saves a
lot of boilerplate of having to pass it around.
Differential Revision: https://reviews.llvm.org/D50111
llvm-svn: 339079
The CoreEngine only gives us a ReturnStmt if the last element in the
CFGBlock is a CFGStmt, otherwise the ReturnStmt is nullptr.
This patch adds support for the case when the last element is a
CFGAutomaticObjDtor, by returning its TriggerStmt as a ReturnStmt.
Differential Revision: https://reviews.llvm.org/D49811
llvm-svn: 338777
Newly added methods allow reasoning about the stack frame of the call (as
opposed to the stack frame on which the call was made, which was always
available) - obtain the stack frame context, obtain parameter regions - even if
the call is not going to be (or was not) inlined, i.e. even if the analysis
has never actually entered the stack frame.
Differential Revision: https://reviews.llvm.org/D49715
llvm-svn: 338474
Because of incomplete support for CXXDefaultArgExpr, we cannot yet commit to
asserting that the same destructor won't be elided twice.
Suppress the assertion failure for now. Proper support is still an open problem.
Differential Revision: https://reviews.llvm.org/D49213
llvm-svn: 338441
This is a refactoring patch; no functional change intended.
The common part of ConstructionContextLayer and ConstructedObjectKey is
factored out into a new structure, ConstructionContextItem.
Various sub-kinds of ConstructionContextItem are enumerated in order to
provide richer information about construction contexts.
Differential Revision: https://reviews.llvm.org/D49210.
llvm-svn: 338439
In r330377 and r338425 we have already identified what constitutes function
argument constructors and added stubs in order to prevent confusing them
with other temporary object constructors.
Now we implement a ConstructionContext sub-class to carry all the necessary
information about the construction site, namely call expression and argument
index.
On the analyzer side, the patch interacts with the recently implemented
pre-C++17 copy elision support in an interesting manner. If on the CFG side we
didn't find a construction context for the elidable constructor, we build
the CFG as if the elidable constructor is not elided, and the non-elided
constructor within it is a simple temporary. But the same problem may occur
in the analyzer: if the elidable constructor has a construction context but
the analyzer doesn't implement such context yet, the analyzer should also
try to skip copy elision and still inline the non-elided temporary constructor.
This was implemented by adding a "roll back" mechanism: when elision fails,
roll back the changes and proceed as if it's a simple temporary. The approach
is wonky, but i'm fine with that as long as it's merely a defensive mechanism
that should eventually go away once all construction contexts become supported.
Differential Revision: https://reviews.llvm.org/D48681.
llvm-svn: 338436
This fix is similar to r337769 and addresses a regression caused by r337167.
When an operation between a nonloc::LocAsInteger and a non-pointer symbol
is performed, the LocAsInteger-specific part of information is lost.
When the non-pointer symbol is collapsing into a constant, we cannot easily
re-evaluate the result, because we need to recover the missing
LocAsInteger-specific information (eg., integer type, or the very fact that
this pointer was at some point converted to an integer).
Add one more defensive check to prevent crashes on trying to simplify a
SymSymExpr with different Loc-ness of operands.
Differential Revision:
llvm-svn: 338420
The note is added in the following situation:
- We are throwing a nullability-related warning on an IVar
- The path goes through a method which *could have* (syntactically
determined) written into that IVar, but did not
rdar://42444460
Differential Revision: https://reviews.llvm.org/D49689
llvm-svn: 338149
Summary:
This patch replaces the current method of getting an `APSInt` from Z3's model by calling generic API method `getBitvector` instead of `Z3_get_numeral_uint64`.
By calling `getBitvector`, there's no need to handle bitvectors with bit width == 128 separately.
And, as a bonus, clang now compiles correctly with Z3 4.7.1.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49818
llvm-svn: 338020
Summary:
Update the documentation of all the classes introduced with the new generic SMT API, most of them were referencing Z3 and how previous operations were being done (like including the context as parameter in a few methods).
Renamed the following methods, so it's clear that the operate on bitvectors:
*`mkSignExt` -> `mkBVSignExt`
*`mkZeroExt` -> `mkBVZeroExt`
*`mkExtract` -> `mkBVExtract`
*`mkConcat` -> `mkBVConcat`
Removed the unecessary methods:
* `getDataExpr`: it was an one line method that called `fromData`
* `mkBitvector(const llvm::APSInt Int)`: it was not being used anywhere
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49799
llvm-svn: 337954
Summary:
The macro was manually expanded in the Z3 backend and this patch adds it back.
Adding the expanded code is dangerous as the macro may change in the future and the expanded code might be left outdated.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49769
llvm-svn: 337923
Summary:
Third patch in the refactoring series, to decouple the SMT Solver from the Refutation Manager (1st: D49668, 2nd: D49767).
The refutation API in the `SMTConstraintManager` was a hack to allow us to create an SMT solver and verify the constraints; it was conceptually wrong from the start. Now, we don't actually need to use the `SMTConstraintManager` and can create an SMT object directly, add the constraints and check them.
While updating the Falsification visitor, I inlined the two functions that were used to collect the constraints and add them to the solver.
As a result of this patch, we could move the SMT API elsewhere and as it's not really dependent on the CSA anymore. Maybe we can create a new dir (utils/smt) for Z3 and future solvers?
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49768
llvm-svn: 337922
Summary:
This is the second part of D49668, and moves all the code that's not specific to a ConstraintManager to SMTSolver.
No functional change intended.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49767
llvm-svn: 337921
Summary:
This patch changes how the SMT bug refutation runs in an equivalent bug report class.
Now, all other visitor are executed until they find a valid bug or mark all bugs as invalid. When the one valid bug is found (and crosscheck is enabled), the SMT refutation checks the satisfiability of this single bug.
If the bug is still valid after checking with Z3, it is returned and a bug report is created. If the bug is found to be invalid, the next bug report in the equivalent class goes through the same process, until we find a valid bug or all bugs are marked as invalid.
Massive speedups when verifying redis/src/rax.c, from 1500s to 10s.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49693
llvm-svn: 337920
Summary:
This patch moves a lot of code from `Z3ConstraintManager` to `SMTConstraintManager`, leaving only the necessary:
* `canReasonAbout` which returns if a Solver can handle a given `SVal` (should be moved to `SMTSolver` in the future).
* `removeDeadBindings`, `assumeExpr` and `print`: methods that need to use `ConstraintZ3Ty`, can probably be moved to `SMTConstraintManager` in the future.
The patch creates a new file, `SMTConstraintManager.cpp` with the moved code. Conceptually, this is move in the right direction and needs further improvements: `SMTConstraintManager` still does a lot of things that are not required by a `ConstraintManager`.
We ought to move the unrelated to `SMTSolver` and remove everything that's not related to a `ConstraintManager`. In particular, we could remove `addRangeConstraints` and `isModelFeasible`, and make the refutation manager create an Z3Solver directly.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: mgorny, xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49668
llvm-svn: 337919
Summary:
Created new SMT generic API.
Small changes to `Z3ConstraintManager` because of the new generic objects (`SMTSort` and `SMTExpr`) returned by `SMTSolver`.
Reviewers: george.karpenkov, NoQ
Reviewed By: george.karpenkov
Subscribers: mgorny, xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49495
llvm-svn: 337918
Summary:
New base class for all future SMT Exprs.
No major changes except moving `areEquivalent` and `getFloatSemantics` outside of `Z3Expr` to keep the class minimal.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49551
llvm-svn: 337917
Summary:
New base class for all future SMT sorts.
The only change is that the class implements methods `isBooleanSort()`, `isBitvectorSort()` and `isFloatSort()` so it doesn't rely on `Z3`'s enum.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49550
llvm-svn: 337916
Summary:
Although it is a big patch, the changes are simple:
1. There is one `Z3_Context` now, member of the `SMTConstraintManager` class.
2. `Z3Expr`, `Z3Sort`, `Z3Model` and `Z3Solver` are constructed with a reference to the `Z3_Context` in `SMTConstraintManager`.
3. All static functions are now members of `Z3Solver`, e.g, the `SMTConstraintManager` now calls `Solver.fromBoolean(false)` instead of `Z3Expr::fromBoolean(false)`.
Most of the patch only move stuff around except:
1. New method `Z3Sort MkSort(const QualType &Ty, unsigned BitWidth)`, that creates a sort based on the `QualType` and its width. Used to simplify the `fromData` method.
Unfortunate consequence of this patch:
1. `getInterpretation` was moved from `Z3Model` class to `Z3Solver`, because it needs to create a `Z3Sort` before returning the interpretation. This can be fixed by changing both `toAPFloat` and `toAPSInt` by removing the dependency of `Z3Sort` (it's only used to check which Sort was created and to retrieve the type width).
Reviewers: NoQ, george.karpenkov, ddcc
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49236
llvm-svn: 337915
Summary:
This patch creates `SMTContext` which will wrap a specific SMT context, through `SMTSolverContext`.
The templated `SMTSolverContext` class it's a simple wrapper around a SMT specific context (currently only used in the Z3 backend), while `Z3Context` inherits `SMTSolverContext<Z3_context>` and implements solver specific operations like initialization and destruction of the context.
This separation was done because:
1. We might want to keep one single context, shared across different `SMTConstraintManager`s. It can be achieved by constructing a `SMTContext`, through a function like `CreateSMTContext(Z3)`, `CreateSMTContext(BOOLECTOR)`, etc. The rest of the CSA only need to know about `SMTContext`, so maybe it's a good idea moving `SMTSolverContext` to a separate header in the future.
2. Any generic SMT operation will only require one `SMTSolverContext`object, which can access the specific context by calling `getContext()`.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49233
llvm-svn: 337914
The note is added in the following situation:
- We are throwing a nullability-related warning on an IVar
- The path goes through a method which *could have* (syntactically
determined) written into that IVar, but did not
rdar://42444460
Differential Revision: https://reviews.llvm.org/D49689
llvm-svn: 337864
Remove an assertion in RangeConstraintManager that expects such symbols to never
appear, while admitting that the constraint manager doesn't yet handle them.
Differential Revision: https://reviews.llvm.org/D49703
llvm-svn: 337769
Patch https://reviews.llvm.org/rC329780 not only rearranges comparisons but
also binary expressions. This latter behavior is not protected by the analyzer
option. Hower, since no complexity threshold is enforced to the symbols this
may result in exponential execution time if the expressions are too complex:
https://bugs.llvm.org/show_bug.cgi?id=38208. For a quick fix we extended the
analyzer option to also cover the additive cases.
This is only a temporary fix, the final solution should be enforcing the
complexity threshold to the symbols.
Differential Revision: https://reviews.llvm.org/D49536
llvm-svn: 337678
Summary:
This patch introduces a new member to SymExpr, which stores the symbol complexity, avoiding recalculating it every time computeComplexity() is called.
Also, increase the complexity of conjured Symbols by one, so it's clear that it has a greater complexity than its underlying symbols.
Reviewers: NoQ, george.karpenkov
Reviewed By: NoQ, george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49232
llvm-svn: 337472
Summary:
An assertion was added in D48205 to catch places where a `nonloc::SymbolVal` was wrapping a `loc` object.
This patch fixes that in the Z3 backend by making the `SValBuilder` object accessible from inherited instances of `SimpleConstraintManager` and calling `SVB.makeSymbolVal(foo)` instead of `nonloc::SymbolVal(foo)`.
Reviewers: NoQ, george.karpenkov
Reviewed By: NoQ
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49430
llvm-svn: 337304
The canonical representation of pointer &SymRegion{$x} casted to boolean is
"$x != 0", not "$x". Assertion added in r337227 catches that.
Differential Revision: https://reviews.llvm.org/D48232
llvm-svn: 337228
In the current SVal hierarchy there are multiple ways of representing certain
values but few are actually used and expected to be seen by the code.
In particular, a value of a symbolic pointer is always represented by a
loc::MemRegionVal that wraps a SymbolicRegion that wraps the pointer symbol
and never by a nonloc::SymbolVal that wraps that symbol directly.
Assert the aforementioned fact. Fix one minor violation of it.
Differential Revision: https://reviews.llvm.org/D48205
llvm-svn: 337227
Only suppress those cases where the null which came from the macro is
relevant to the bug, and was not overwritten in between.
rdar://41497323
Differential Revision: https://reviews.llvm.org/D48856
llvm-svn: 337213
Summary:
In `toAPSInt`, the Z3 backend was not checking the variable `Int`'s type and was always generating unsigned `APSInt`s.
This was found by accident when I removed:
```
llvm::APSInt ConvertedLHS, ConvertedRHS;
QualType LTy, RTy;
std::tie(ConvertedLHS, LTy) = fixAPSInt(*LHS);
std::tie(ConvertedRHS, RTy) = fixAPSInt(*RHS);
- doIntTypePromotion<llvm::APSInt, Z3ConstraintManager::castAPSInt>(
- ConvertedLHS, LTy, ConvertedRHS, RTy);
return BVF.evalAPSInt(BSE->getOpcode(), ConvertedLHS, ConvertedRHS);
```
And the `BasicValueFactory` started to complain about different `signedness`.
Reviewers: george.karpenkov, NoQ, ddcc
Reviewed By: ddcc
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49305
llvm-svn: 337169
Summary:
This patch removes the constraint dropping when taint tracking is disabled.
It also voids the crash reported in D28953 by treating a SymSymExpr with non pointer symbols as an opaque expression.
Updated the regressions and verifying the big projects now; I'll update here when they're done.
Based on the discussion on the mailing list and the patches by @ddcc.
Reviewers: george.karpenkov, NoQ, ddcc, baloghadamsoftware
Reviewed By: george.karpenkov
Subscribers: delcypher, llvm-commits, rnkovacs, xazax.hun, szepet, a.sidorin, ddcc
Differential Revision: https://reviews.llvm.org/D48650
llvm-svn: 337167
This allows more qualification conversions, eg. conversion from
'int *(*)[]' -> 'const int *const (*)[]'
is now permitted, along with all the consequences of that: more types
are similar, more cases are permitted by const_cast, and conversely,
fewer "casting away constness" cases are permitted by reinterpret_cast.
llvm-svn: 336745
Summary:
This adds an option, max-symbol-complexity, so an user can set the maximum symbol complexity threshold.
Note that the current behaviour is equivalent to max complexity = 0, when taint analysis is not enabled and tests show that in a number of tests, having complexity = 25 yields the same results as complexity = 10000.
This patch was extracted and modified from Dominic Chen's patch, D35450.
Reviewers: george.karpenkov, NoQ, ddcc
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D49093
llvm-svn: 336671
Summary: In the provided test case the PathDiagnostic compare function was not able to find a difference.
Reviewers: xazax.hun, NoQ, dcoughlin, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: a_sidorin, szepet, rnkovacs, a.sidorin, mikhail.ramalho, cfe-commits
Differential Revision: https://reviews.llvm.org/D48474
llvm-svn: 336275
Now, instead of adding the constraints when they are removed, this patch adds them when they first appear and, since we walk the bug report backward, it should be the last set of ranges generated by the CSA for a given symbol.
These are the number before and after the patch:
```
Project | current | patch |
tmux | 283.222 | 123.052 |
redis | 614.858 | 400.347 |
openssl | 308.292 | 307.149 |
twin | 274.478 | 245.411 |
git | 547.687 | 477.335 |
postgresql | 2927.495 | 2002.526 |
sqlite3 | 3264.305 | 1028.416 |
```
Major speedups in tmux and sqlite (less than half of the time), redis and postgresql were about 25% faster while the rest are basically the same.
Reviewers: NoQ, george.karpenkov
Reviewed By: george.karpenkov
Subscribers: rnkovacs, xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D48565
llvm-svn: 336002
The refutation manager is removing a true bug from the test in this patch.
The problem is that the following constraint:
```
(conj_$1{struct o *}) - (reg_$3<int * r>): [-9223372036854775808, 0]
```
is encoded as:
```
(and (bvuge (bvsub $1 $3) #x8000000000000000)
(bvule (bvsub $1 $3) #x0000000000000000))
```
The issue is that unsigned comparisons (bvuge and bvule) are being generated instead of signed comparisons (bvsge and bvsle).
When generating the expressions:
```
(conj_$1{p *}) - (reg_$3<int * r>) >= -9223372036854775808
```
and
```
(conj_$1{p *}) - (reg_$3<int * r>) <= 0
```
both -9223372036854775808 and 0 are casted to pointer type and `LTy->isSignedIntegerOrEnumerationType()` in `Z3ConstraintManager::getZ3BinExpr` only checks if the type is signed, not if it's a pointer.
Reviewers: NoQ, george.karpenkov, ddcc
Subscribers: rnkovacs, NoQ, george.karpenkov, ddcc, xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D48324
llvm-svn: 335926
If range [m .. n] is stored for symbolic expression A - B, then we can deduce the range for B - A which is [-n .. -m]. This is only true for signed types, unless the range is [0 .. 0].
Differential Revision: https://reviews.llvm.org/D35110
llvm-svn: 335814
The ProgramState::assumeInBound() API is used by checkers to make an assumption
that a certain array index is within the array's bounds (i.e. is greater than or
equal to 0 and is less than the length of the array). When the type of the
index was unspecified by the caller, it assumed that the type is 'int', which
caused some indices and sizes to truncate during calculations.
Use ArrayIndexTy by default instead, which is used by the analyzer to represent
index types and is currently hardcoded to long long.
Patch by Bevin Hansson!
Differential Revision: https://reviews.llvm.org/D46944
llvm-svn: 335803
r335795 adds copy elision information to CFG. This commit allows static analyzer
to elide elidable copy constructors by constructing the objects that were
previously subject to elidable copy directly in the target region of the copy.
The chain of elided constructors may potentially be indefinitely long. This
only happens when the object is being returned from a function which in turn is
returned from another function, etc.
NRVO is not supported yet.
Differential Revision: https://reviews.llvm.org/D47671
llvm-svn: 335800
When a temporary object is materialized and through that obtain lifetime that
is longer than the duration of the full-expression, it does not require a
temporary object destructor; it will be destroyed in a different manner.
Therefore it's not necessary to include CXXBindTemporaryExpr into the
construction context for such temporary in the CFG only to make clients
throw it away.
Differential Revision: https://reviews.llvm.org/D47667
llvm-svn: 335798
When an object's class provides no destructor, it's less important to
materialize that object properly because we don't have to model the destructor
correctly, so previously we skipped the support for these syntax patterns.
Additionally, fix support for construction contexts of "static temporaries"
(temporaries that are lifetime-extended by static references) because
it turned out that we only had tests for them without destructors, which caused
us to regress when we re-introduced the construction context for such
temporaries.
Differential Revision: https://reviews.llvm.org/D47658
llvm-svn: 335796
Before C++17 copy elision was optional, even if the elidable copy/move
constructor had arbitrary side effects. The elidable constructor is present
in the AST, but marked as elidable.
In these cases CFG now contains additional information that allows its clients
to figure out if a temporary object is only being constructed so that to pass
it to an elidable constructor. If so, it includes a reference to the elidable
constructor's construction context, so that the client could elide the
elidable constructor and construct the object directly at its final destination.
Differential Revision: https://reviews.llvm.org/D47616
llvm-svn: 335795
In the current implementation, we run visitors until the fixed point is
reached.
That is, if a visitor adds another visitor, the currently processed path
is destroyed, all diagnostics is discarded, and it is regenerated again,
until it's no longer modified.
This pattern has a few negative implications:
- This loop does not even guarantee to terminate.
E.g. just imagine two visitors bouncing a diagnostics around.
- Performance-wise, e.g. for sqlite3 all visitors are being re-run at
least 10 times for some bugs.
We have already seen a few reports where it leads to timeouts.
- If we want to add more computationally intense visitors, this will
become worse.
- From architectural standpoint, the current layout requires copying
visitors, which is conceptually wrong, and can be annoying (e.g. no
unique_ptr on visitors allowed).
The proposed change is a much simpler architecture: the outer loop
processes nodes upwards, and whenever the visitor is added it only
processes current nodes and above, thus guaranteeing termination.
Differential Revision: https://reviews.llvm.org/D47856
llvm-svn: 335666
ExprWithCleanups wraps full-expressions that require temporary destructors
and highlights the moment of time in which these destructors need to be called
(i.e., "at the end of the full-expression...").
Such expressions don't necessarily return an object; they may return anything,
including a null or undefined value.
When the analyzer tries to understand where the null or undefined value came
from in order to present better diagnostics to the user, it will now skip
any ExprWithCleanups it encounters and look into the expression itself.
Differential Revision: https://reviews.llvm.org/D48204
llvm-svn: 335559
Conservative evaluation of a C++ method call would invalidate the object,
as long as the method is not const or the object has mutable fields.
When checking for mutable fields, we need to scan the type of the object on
which the method is called, which may be more specific than the type of the
object on which the method is defined, hence we look up the type from the
this-argument expression.
If arrow syntax or implicit-this syntax is used, this-argument expression
has pointer type, not record type, and lookup accidentally failed for that
reason. Obtain object type correctly.
Differential Revision: https://reviews.llvm.org/D48460
llvm-svn: 335555
This diff includes the logic for setting the precision bits for each primary fixed point type in the target info and logic for initializing a fixed point literal.
Fixed point literals are declared using the suffixes
```
hr: short _Fract
uhr: unsigned short _Fract
r: _Fract
ur: unsigned _Fract
lr: long _Fract
ulr: unsigned long _Fract
hk: short _Accum
uhk: unsigned short _Accum
k: _Accum
uk: unsigned _Accum
```
Errors are also thrown for illegal literal values
```
unsigned short _Accum u_short_accum = 256.0uhk; // expected-error{{the integral part of this literal is too large for this unsigned _Accum type}}
```
Differential Revision: https://reviews.llvm.org/D46915
llvm-svn: 335148
Summary:
If a constraint is something like:
```
$0 = [1,1]
```
it'll now be created as:
```
assert($0 == 1)
```
instead of:
```
assert($0 >= 1 && $0 <= 1)
```
In general, ~3% speedup when solving per query in my machine. Biggest improvement was when verifying sqlite3, total time went down from 3000s to 2200s.
I couldn't create a test for this as there is no way to dump the formula yet. D48221 adds a method to dump the formula but there is no way to do it from the command line.
Also, a test that prints the formula will most likely fail in the future, as different solvers print the formula in different formats.
Reviewers: NoQ, george.karpenkov, ddcc
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D48227
llvm-svn: 335116
Summary:
New method dump the SMT formula and the Z3 implementation.
There is no test because I only used it for debugging.
However, if requested, I can add an option to the static analyzer to dump the formula (whole program? per path?), maybe something like the trimmed graph but for SMT formulas.
Reviewers: NoQ, george.karpenkov, ddcc
Reviewed By: george.karpenkov
Subscribers: xazax.hun, szepet, a.sidorin
Differential Revision: https://reviews.llvm.org/D48221
llvm-svn: 334891
Not contexts themselves, but rather support for them in the analyzer.
Such construction contexts appear when C++17 mandatory copy elision occurs
while returning an object from a function, and presence of a destructor causes
a CXXBindTemporaryExpr to appear in the AST.
Additionally, such construction contexts may be chained, because a return-value
construction context doesn't really explain where the object is being returned
into, but only points to the parent stack frame, where the object may be
consumed by literally anything including another return statement. This
behavior is now modeled correctly by the analyzer as long as the object is not
returned beyond the boundaries of the analysis.
Differential Revision: https://reviews.llvm.org/D47405
llvm-svn: 334684
Not contexts themselves, but rather support for them in the analyzer.
Such construction contexts appear when C++17 mandatory copy elision occurs
during initialization, and presence of a destructor causes a
CXXBindTemporaryExpr to appear in the AST.
Similar C++17-specific constructors for return values are still to be supported.
Differential Revision: https://reviews.llvm.org/D47351
llvm-svn: 334683
The reasoning behind this change is similar to the previous commit, r334681.
Because members are already in scope when construction occurs, we are not
suffering from liveness problems, but we still want to figure out if the object
was constructed with construction context, because in this case we'll be able
to avoid trivial copy, which we don't always model perfectly. It'd also have
more importance when copy elision is implemented.
This also gets rid of the old CFG look-behind mechanism.
Differential Revision: https://reviews.llvm.org/D47350
llvm-svn: 334682
The very idea of construction context implies that first the object is
constructed, and then later, in a separate moment of time, the constructed
object goes into scope, i.e. becomes "live".
Most construction contexts require path-sensitive tracking of the constructed
object region in order to compute the outer expressions accordingly before
the object becomes live.
Semantics of simple variable construction contexts don't immediately require
that such tracking happens in path-sensitive manner, but shortcomings of the
analyzer force us to track it path-sensitively as well. Namely, whether
construction context was available at all during construction is a
path-sensitive information. Additionally, path-sensitive tracking takes care of
our liveness problems that kick in as the temporal gap between construction and
going-into-scope becomes larger (eg., due to copy elision).
Differential Revision: https://reviews.llvm.org/D47305
llvm-svn: 334681
When analyzing C++ code, a common operation in the analyzer is to discover
target region for object construction by looking at CFG metadata ("construction
contexts"), and then track the region path-sensitively until object construction
is resolved, where the amount of information, again, depends on construction
context.
Scan construction context only once for both purposes.
Differential Revision: https://reviews.llvm.org/D47304
llvm-svn: 334678
Loop widening can invalidate a reference. If the analyzer attempts to visit the
destructor to a non-existent reference, it will crash. This patch ensures that
the reference is preserved.
https://reviews.llvm.org/D47044
llvm-svn: 334554
removeInvalidation is a very problematic API, as it makes suppression
order-dependent.
Moreover, it was used only once, and could be rewritten in a much
cleaner way.
Differential Revision: https://reviews.llvm.org/D48045
llvm-svn: 334542
BugReporter.cpp is already severely overloaded, and those dump methods
are on PathDiagnostics and should belong in the corresponding
implementation file.
Differential Revision: https://reviews.llvm.org/D48035
llvm-svn: 334541
getEndPath is a problematic API, because it's not clear when it's called
(hint: not always at the end of the path), it crashes at runtime with
more than one non-nullptr returning implementation, and diagnostics
internal depend on it being called at some exact place.
However, most visitors don't actually need that: all they want is a
function consistently called after all nodes are traversed, to perform
finalization and to decide whether invalidation is needed.
Differential Revision: https://reviews.llvm.org/D48042
llvm-svn: 334540
Once we removed AlternateExtensive, I've looked closer into the
difference between Minimal and Extensive, and turns out, the difference
was not that large.
Differential Revision: https://reviews.llvm.org/D47756
llvm-svn: 334525
Rename AlternateExtensive to Extensive.
In 2013, five years ago, we have switched to AlternateExtensive
diagnostics by default, and Extensive was available under unused,
undocumented flag.
This change remove the flag, renames the Alternate
diagnostic to Extensive (as it's no longer Alternate), and ports the
test.
Differential Revision: https://reviews.llvm.org/D47670
llvm-svn: 334524
This breaks the OpenFlags enumeration into two separate
enumerations: OpenFlags and CreationDisposition. The first
controls the behavior of the API depending on whether or not
the target file already exists, and is not a flags-based
enum. The second controls more flags-like values.
This yields a more easy to understand API, while also allowing
flags to be passed to the openForRead api, where most of the
values didn't make sense before. This also makes the apis more
testable as it becomes easy to enumerate all the configurations
which make sense, so I've added many new tests to exercise all
the different values.
llvm-svn: 334221
Temporary object constructor inlining was disabled in r326240 for code like
const int &x = A().x;
because automatic destructor for the lifetime-extended object A() was not
working correctly in CFG.
CFG was fixed in r333941, so inlining can be re-enabled. CFG for lifetime
extension through aggregates still needs to be fixed.
Differential Revision: https://reviews.llvm.org/D44239
llvm-svn: 333946
Summary: This is a prototype of a bug reporter visitor that invalidates bug reports by re-checking constraints of certain states on the bug path using the Z3 constraint manager backend. The functionality is available under the `crosscheck-with-z3` analyzer config flag.
Reviewers: george.karpenkov, NoQ, dcoughlin, rnkovacs
Reviewed By: george.karpenkov
Subscribers: rnkovacs, NoQ, george.karpenkov, dcoughlin, xbolva00, ddcc, mikhail.ramalho, MTC, fhahn, whisperity, baloghadamsoftware, szepet, a.sidorin, gsd, dkrupp, xazax.hun, cfe-commits
Differential Revision: https://reviews.llvm.org/D45517
llvm-svn: 333903
Summary:
This patch implements a simple SMTConstraintManager API, and requires the implementation of two methods for now: `addRangeConstraints` and `isModelFeasible`.
Update Z3ConstraintManager to inherit it and implement required methods.
I also moved the method to dump the SMT formula from D45517 to this patch.
This patch was created based on the reviews from D47640.
Reviewers: george.karpenkov, NoQ, ddcc, dcoughlin
Reviewed By: george.karpenkov
Differential Revision: https://reviews.llvm.org/D47689
llvm-svn: 333899
Summary:
Moved `RangedConstraintManager` header from `lib/StaticAnalyzer/Core/` to `clang/StaticAnalyzer/Core/PathSensitive/`. No changes to the code.
Reviewers: NoQ, george.karpenkov, dcoughlin
Reviewed By: george.karpenkov
Subscribers: NoQ, george.karpenkov, dcoughlin, ddcc
Differential Revision: https://reviews.llvm.org/D47640
llvm-svn: 333862
ExprEngine already maintains three internal program state traits to track
path-sensitive information related to object construction: pointer returned by
operator new, and pointer to temporary object for two different purposes - for
destruction and for lifetime extension. We'll need to add 2-3 more in a few
follow-up commits.
Merge these traits into one because they all essentially serve one purpose and
work similarly.
Differential Revision: https://reviews.llvm.org/D47303
llvm-svn: 333719
Summary: Clang does not have a corresponding QualType for a 1-bit APSInt, so use the BoolTy and extend the APSInt. Split from D35450. Fixes PR37622.
Reviewers: george.karpenkov, NoQ
Subscribers: mikhail.ramalho, xazax.hun, szepet, rnkovacs, cfe-commits, a.sidorin
Differential Revision: https://reviews.llvm.org/D47603
llvm-svn: 333704
Memoize simplification so that we didn't need to simplify the same symbolic
expression twice within the same program state.
Gives ~25% performance boost on the artificial test in test/Analysis/hangs.c.
Differential Revision: https://reviews.llvm.org/D47402
llvm-svn: 333671
When neither LHS nor RHS of a binary operator expression can be simplified,
return the original expression instead of re-evaluating the binary operator.
Such re-evaluation was causing recusrive re-simplification which caused
the algorithmic complexity to explode.
Differential Revision: https://reviews.llvm.org/D47155
llvm-svn: 333670
Summary: If the access is out of bounds, return UndefinedVal. If it is missing an explicit init, return the implicit zero value it must have.
Reviewers: NoQ, xazax.hun, george.karpenkov
Reviewed By: NoQ
Subscribers: szepet, rnkovacs, a.sidorin, cfe-commits
Differential Revision: https://reviews.llvm.org/D46823
llvm-svn: 333417
Because template parameter lists were not displayed
in the plist output, it was difficult to decide in
some cases whether a given checker found a true or a
false positive. This patch aims to correct this.
Differential Revision: https://reviews.llvm.org/D46933
llvm-svn: 333275
Summary: I could also move `RangedConstraintManager.h` under `include/` if you agree as it seems slightly out of place under `lib/`.
Patch by Réka Kovács
Reviewers: NoQ, george.karpenkov, dcoughlin, rnkovacs
Reviewed By: NoQ
Subscribers: mikhail.ramalho, whisperity, xazax.hun, baloghadamsoftware, szepet, a.sidorin, dkrupp, cfe-commits
Differential Revision: https://reviews.llvm.org/D45920
llvm-svn: 333179
The DEBUG() macro is very generic so it might clash with other projects.
The renaming was done as follows:
- git grep -l 'DEBUG' | xargs sed -i 's/\bDEBUG\s\?(/LLVM_DEBUG(/g'
- git diff -U0 master | ../clang/tools/clang-format/clang-format-diff.py -i -p1 -style LLVM
Explicitly avoided changing the strings in the clang-format tests.
Differential Revision: https://reviews.llvm.org/D44975
llvm-svn: 332350
This is similar to the LLVM change https://reviews.llvm.org/D46290.
We've been running doxygen with the autobrief option for a couple of
years now. This makes the \brief markers into our comments
redundant. Since they are a visual distraction and we don't want to
encourage more \brief markers in new code either, this patch removes
them all.
Patch produced by
for i in $(git grep -l '\@brief'); do perl -pi -e 's/\@brief //g' $i & done
for i in $(git grep -l '\\brief'); do perl -pi -e 's/\\brief //g' $i & done
Differential Revision: https://reviews.llvm.org/D46320
llvm-svn: 331834
We weren't invalidating our unions correctly. The previous behavior in
invalidateRegionsWorker::VisitCluster() was to direct-bind an UnknownVal
to the union (at offset 0).
For that reason we were never actually loading default bindings from our unions,
because there never was any default binding to load, and the value
that is presumed when there's no default binding to load
is usually completely incorrect (eg. UndefinedVal for stack unions).
The new behavior is to default-bind a conjured symbol (of irrelevant type)
to the union that's being invalidated, similarly to what we do for structures
and classes. Then it becomes safe to load the value properly.
Differential Revision: https://reviews.llvm.org/D45241
llvm-svn: 331563
C allows us to write any bytes into any memory region. When loading weird bytes
from memory regions of known types, the analyzer is required to make sure that
the loaded value makes sense by casting it to an appropriate type.
Fix such cast for loading values that represent void pointers from non-void
pointer type places.
Differential Revision: https://reviews.llvm.org/D46415
llvm-svn: 331562
The bindDefault() API of the ProgramState allows setting a default value
for reads from memory regions that were not preceded by writes.
It was used for implementing C++ zeroing constructors (i.e. default constructors
that boil down to setting all fields of the object to 0).
Because differences between zeroing consturctors and other forms of default
initialization have been piling up (in particular, zeroing constructors can be
called multiple times over the same object, probably even at the same offset,
requiring a careful and potentially slow cleanup of previous bindings in the
RegionStore), we split the API in two: bindDefaultInitial() for modeling
initial values and bindDefaultZero() for modeling zeroing constructors.
This fixes a few assertion failures from which the investigation originated.
The imperfect protection from both inability of the RegionStore to support
binding extents and lack of information in ASTRecordLayout has been loosened
because it's, well, imperfect, and it is unclear if it fixing more than it
was breaking.
Differential Revision: https://reviews.llvm.org/D46368
llvm-svn: 331561
Many glvalue expressions aren't of their respective reference type -
they are simply glvalues of their value type.
This was causing problems when we were trying to obtain type of the original
expression while evaluating certain glvalue bit-casts.
Fixed by artificially forging a reference type to provide to the casting
procedure.
Differential Revision: https://reviews.llvm.org/D46224
llvm-svn: 331558
When loading from a variable or a field that is declared as constant,
the analyzer will try to inspect its initializer and constant-fold it.
Upon success, the analyzer would skip normal load and return the respective
constant.
The new behavior also applies to fields/elements of brace-initialized structures
and arrays.
Patch by Rafael Stahl!
Differential Revision: https://reviews.llvm.org/D45774
llvm-svn: 331556
FunctionProtoType.
We previously re-evaluated the expression each time we wanted to know whether
the type is noexcept or not. We now evaluate the expression exactly once.
This is not quite "no functional change": it fixes a crasher bug during AST
deserialization where we would try to evaluate the noexcept specification in a
situation where we have not deserialized sufficient portions of the AST to
permit such evaluation.
llvm-svn: 331428
Summary:
The filename is currently taken from the start of the path, while the
line and column are taken from the end of the path.
This didn't matter until cross-file path reporting was added.
Reviewers: george.karpenkov, dcoughlin, vlad.tsyrklevich
Reviewed By: george.karpenkov, vlad.tsyrklevich
Subscribers: xazax.hun, szepet, a.sidorin, cfe-commits
Differential Revision: https://reviews.llvm.org/D45611
llvm-svn: 331361
When a '>>' token is split into two '>' tokens (in C++11 onwards), or (as an
extension) when we do the same for other tokens starting with a '>', we can't
just use a location pointing to the first '>' as the location of the split
token, because that would result in our miscomputing the length and spelling
for the token. As a consequence, for example, a refactoring replacing 'A<X>'
with something else would sometimes replace one character too many, and
similarly diagnostics highlighting a template-id source range would highlight
one character too many.
Fix this by creating an expansion range covering the first character of the
'>>' token, whose spelling is '>'. For this to work, we generalize the
expansion range of a macro FileID to be either a token range (the common case)
or a character range (used in this new case).
llvm-svn: 331155
Avoid crash when the sub-expression of operator delete[] is of array type.
This is not the same as simply using a delete[] syntax.
We're still not properly calling destructors in this case in the analyzer.
Differential Revision: https://reviews.llvm.org/D46146
llvm-svn: 331014
If 'A' is a C++ aggregate with a reference field of type 'C', in code like
A a = { C() };
C() is lifetime-extended by 'a'. The analyzer wasn't expecting this pattern and
crashing. Additionally, destructors aren't added in the CFG for this case,
so for now we shouldn't be inlining the constructor for C().
Differential Revision: https://reviews.llvm.org/D46037
llvm-svn: 330882
Normally the analyzer begins path-sensitive analysis from functions within
the main file, even though the path is allowed to go through any functions
within the translation unit.
When a recent version of WebKit is compiled, the "unified sources" technique
is used, that assumes #including multiple code files into a single main file.
Such file would have no functions defined in it, so the analyzer wouldn't be
able to find any entry points for path-sensitive analysis.
This patch pattern-matches unified file names that are similar to those
used by WebKit and allows the analyzer to find entry points in the included
code files. A more aggressive/generic approach is being planned as well.
Differential Revision: https://reviews.llvm.org/D45839
llvm-svn: 330876
Note diagnostic pieces are an additional way of highlighting code sections to
the user. They aren't part of the normal path diagnostic sequence. They can
also be attached to path-insensitive reports.
Notes are already supported by the text output and scan-build.
Expanding our machine-readable plist output format to be able to represent notes
opens up the possibility for various analyzer GUIs to pick them up.
Patch by Umann Kristóf!
Differential Revision: https://reviews.llvm.org/D45407
llvm-svn: 330766
Printing of ConcreteInts with size >64 bits resulted in assertion failure
in get[Z|S]ExtValue() because these methods are only allowed to be used
with integers of 64 max bit width. This patch fixes the issue.
llvm-svn: 330605
Summary: `TaintBugVisitor` is a universal visitor, and many checkers rely on it, such as `ArrayBoundCheckerV2.cpp`, `DivZeroChecker.cpp` and `VLASizeChecker.cpp`. Moving `TaintBugVisitor` to `BugReporterVisitors.h` enables other checker can also track where `tainted` value came from.
Reviewers: NoQ, george.karpenkov, xazax.hun
Reviewed By: george.karpenkov
Subscribers: szepet, rnkovacs, a.sidorin, cfe-commits, MTC
Differential Revision: https://reviews.llvm.org/D45682
llvm-svn: 330596
If a pointer cast fails (evaluates to an UnknownVal, i.e. not implemented in the
analyzer) and such cast is in fact the last use of the pointer, the pointer
symbol is no longer referenced by the program state and a leak is
(mis-)diagnosed.
"Escape" the pointer upon a failed cast, i.e. inform the checker that we can no
longer reliably track it.
Differential Revision: https://reviews.llvm.org/D45698
llvm-svn: 330380
Summary:
`this` pointer is not an l-value, although we have modeled `CXXThisRegion` for `this` pointer, we can only bind it once, which is when we start to inline method. And this patch fixes https://bugs.llvm.org/show_bug.cgi?id=35506.
In addition, I didn't find any other cases other than loop-widen that could invalidate `this` pointer.
Reviewers: NoQ, george.karpenkov, a.sidorin, seaneveson, szepet
Reviewed By: NoQ
Subscribers: xazax.hun, rnkovacs, cfe-commits, MTC
Differential Revision: https://reviews.llvm.org/D45491
llvm-svn: 330095
Expression rearrangement in SValBuilder (see rL329780) crashes with an assert if the type of the integer is different from the type of the symbol. This fix adds a check that prevents rearrangement in such cases.
Differential Revision: https://reviews.llvm.org/D45557
llvm-svn: 330064
Since the range-based constraint manager (default) is weak in handling comparisons where symbols are on both sides it is wise to rearrange them to have symbols only on the left side. Thus e.g. A + n >= B + m becomes A - B >= m - n which enables the constraint manager to store a range m - n .. MAX_VALUE for the symbolic expression A - B. This can be used later to check whether e.g. A + k == B + l can be true, which is also rearranged to A - B == l - k so the constraint manager can check whether l - k is in the range (thus greater than or equal to m - n).
The restriction in this version is the the rearrangement happens only if both the symbols and the concrete integers are within the range [min/4 .. max/4] where min and max are the minimal and maximal values of their type.
The rearrangement is not enabled by default. It has to be enabled by using -analyzer-config aggressive-relational-comparison-simplification=true.
Co-author of this patch is Artem Dergachev (NoQ).
Differential Revision: https://reviews.llvm.org/D41938
llvm-svn: 329780
Found via codespell -q 3 -I ../clang-whitelist.txt
Where whitelist consists of:
archtype
cas
classs
checkk
compres
definit
frome
iff
inteval
ith
lod
methode
nd
optin
ot
pres
statics
te
thru
Patch by luzpaz! (This is a subset of D44188 that applies cleanly with a few
files that have dubious fixes reverted.)
Differential revision: https://reviews.llvm.org/D44188
llvm-svn: 329399
removeUnneededCalls() is responsible for removing path diagnostic pieces within
functions that don't contain "interesting" events. It makes bug reports
much tidier.
When a stack frame is known to be interesting, the function doesn't descend
into it to prune anything within it, even other callees that are totally boring.
Fix the function to prune boring callees in interesting stack frames.
Differential Revision: https://reviews.llvm.org/D45117
llvm-svn: 329102
Summary:
The original implementation in the `LoopUnrolling.cpp` didn't consider the case where the counter is unsigned. This case is only handled in `simpleCondition()`, but this is not enough, we also need to deal with the unsinged counter with the counter initialization.
Since `IntegerLiteral` is `signed`, there is a `ImplicitCastExpr<IntegralCast>` in `unsigned counter = IntergerLiteral`. This patch add the `ignoringParenImpCasts()` in the `IntegerLiteral` matcher.
Reviewers: szepet, a.sidorin, NoQ, george.karpenkov
Reviewed By: szepet, george.karpenkov
Subscribers: xazax.hun, rnkovacs, cfe-commits, MTC
Differential Revision: https://reviews.llvm.org/D45086
llvm-svn: 328919
Achieves almost a 200% speedup on the example where the performance of
visitors was problematic.
Performance on sqlite3 is unaffected.
rdar://38818362
Differential Revision: https://reviews.llvm.org/D45113
llvm-svn: 328911
Pointer arithmetic on null or undefined pointers results in null or undefined
pointers. This is obvious for undefined pointers; for null pointers it follows
from our incorrect-but-somehow-working approach that declares that 0 (Loc)
doesn't necessarily represent a pointer of numeric address value 0, but instead
it represents any pointer that will cause a valid "null pointer dereference"
issue when dereferenced.
For now we've been seeing through pointer arithmetic at the original dereference
expression, i.e. in bugreporter::getDerefExpr(), but not during further
investigation of the value's origins in bugreporter::trackNullOrUndefValue().
The patch fixes it.
Differential Revision: https://reviews.llvm.org/D45071
llvm-svn: 328896
Not enough work has been done so far to ensure correctness of construction
contexts in the CFG when C++17 copy elision is in effect, so for now we
should drop construction contexts in the CFG and in the analyzer when
they seem different from what we support anyway.
This includes initializations with conditional operators and return values
across multiple stack frames.
Differential Revision: https://reviews.llvm.org/D44854
llvm-svn: 328893
r327219 added wrappers to std::sort which randomly shuffle the container before
sorting. This will help in uncovering non-determinism caused due to undefined
sorting order of objects having the same key.
To make use of that infrastructure we need to invoke llvm::sort instead of
std::sort.
llvm-svn: 328636
Extended the matched assignment operators when checking for bound changes in a body of the loop by using the freshly added isAssignmentOperator matcher.
This covers all the (current) possible assignments, tests added as well.
Differential Revision: https://reviews.llvm.org/D38921
llvm-svn: 328619
Changes the analyzer to believe that methods annotated with _Nonnull
from system frameworks indeed return non null objects.
Local methods with such annotation are still distrusted.
rdar://24291919
Differential Revision: https://reviews.llvm.org/D44341
llvm-svn: 328282
Current location is very confusing, especially because there is already
WorkList.h, and other code in CoreEngine.cpp is not related to work list
implementation.
Differential Revision: https://reviews.llvm.org/D44759
llvm-svn: 328280
When a temporary is constructed with a proper construction context, it should
be safe to inline the destructor. We have added suppressions for some of the
common false positives caused by such inlining, so there should be - and from my
observations there indeed is - more benefit than harm from enabling destructor
inlining.
Differential Revision: https://reviews.llvm.org/D44721
llvm-svn: 328258
CXXCtorInitializer-based constructors are also affected by the C++17 mandatory
copy elision, like variable constructors and return value constructors.
Extend r328248 to support those.
Differential Revision: https://reviews.llvm.org/D44763
llvm-svn: 328255
Function return values can be constructed directly in variables or passed
directly into return statements, without even an elidable copy in between.
This is how the C++17 mandatory copy elision AST behaves. The behavior we'll
have in such cases is the "old" behavior that we've had before we've
implemented destructor inlining and proper lifetime extension support.
Differential Revision: https://reviews.llvm.org/D44755
llvm-svn: 328253
In C++17 copy elision is mandatory for variable and return value constructors
(as long as it doesn't involve type conversion) which results in AST that does
not contain elidable constructors in their usual places. In order to provide
construction contexts in this scenario we need to cover more AST patterns.
This patch makes the CFG prepared for these scenarios by:
- Fork VariableConstructionContext and ReturnedValueConstructionContext into
two different sub-classes (each) one of which indicates the C++17 case and
contains a reference to an extra CXXBindTemporaryExpr.
- Allow CFGCXXRecordTypedCall element to accept VariableConstructionContext and
ReturnedValueConstructionContext as its context.
Differential Revision: https://reviews.llvm.org/D44597
llvm-svn: 328248
Also use the opportunity to clean up the code and remove unnecessary duplication.
rdar://37625895
Differential Revision: https://reviews.llvm.org/D44594
llvm-svn: 327926
My compiler (clang-3.8) complains that the RCC variable is unused.
That's not really true, as it's checked by the if-declaration, but it's
also kinda true, because we don't need to declaration if we only check
it in the if statement.
In reality, all this means that the dyn_cast<> can be replaced by isa<>,
so that's what I do here.
llvm-svn: 327491
Properly perform destruction and lifetime extension of such temporaries.
C++ object-type return values of conservatively evaluated functions are now
represented as compound values of well-defined temporary object regions. The
function creates a region that represents the temporary object and will later
be used for destruction or materialization, invalidates it, and returns the
invalidated compound value of the object.
Differential Revision: https://reviews.llvm.org/D44131
llvm-svn: 327348
This patch uses the newly added CFGCXXRecordTypedCall element at the call site
of the caller to construct the return value within the callee directly into the
caller's stack frame. This way it is also capable of populating the temporary
destructor and lifetime extension maps for the temporary, which allows
temporary destructors and lifetime extension to work correctly.
This patch does not affect temporaries that were returned from conservatively
evaluated functions.
Differential Revision: https://reviews.llvm.org/D44124
llvm-svn: 327345
This patch adds a new CFGStmt sub-class, CFGCXXRecordTypedCall, which replaces
the regular CFGStmt for the respective CallExpr whenever the CFG has additional
information to provide regarding the lifetime of the returned value.
This additional call site information is represented by a ConstructionContext
(which was previously used for CFGConstructor elements) that provides references
to CXXBindTemporaryExpr and MaterializeTemporaryExpr that surround the call.
This corresponds to the common C++ calling convention solution of providing
the target address for constructing the return value as an auxiliary implicit
argument during function call.
One of the use cases for such extra context at the call site would be to perform
any sort of inter-procedural analysis over the CFG that involves functions
returning objects by value. In this case the elidable constructor at the return
site would construct the object explained by the context at the call site, and
its lifetime would also be managed by the caller, not the callee.
The extra context would also be useful for properly handling the return-value
temporary at the call site, even if the callee is not being analyzed
inter-procedurally.
Differential Revision: https://reviews.llvm.org/D44120
llvm-svn: 327343
This patch adds two new CFG elements CFGScopeBegin and CFGScopeEnd that indicate
when a local scope begins and ends respectively. We use first VarDecl declared
in a scope to uniquely identify it and add CFGScopeBegin and CFGScopeEnd elements
into corresponding basic blocks.
Differential Revision: https://reviews.llvm.org/D16403
llvm-svn: 327258
Fangrui Song