Commit Graph

2816 Commits

Author SHA1 Message Date
isuckatcs 996b092c5e [analyzer] Lambda capture non-POD type array
This patch introduces a new `ConstructionContext` for
lambda capture. This `ConstructionContext` allows the
analyzer to construct the captured object directly into
it's final region, and makes it possible to capture
non-POD arrays.

Differential Revision: https://reviews.llvm.org/D129967
2022-07-26 09:40:25 +02:00
isuckatcs 8a13326d18 [analyzer] ArrayInitLoopExpr with array of non-POD type
This patch introduces the evaluation of ArrayInitLoopExpr
in case of structured bindings and implicit copy/move
constructor. The idea is to call the copy constructor for
every element in the array. The parameter of the copy
constructor is also manually selected, as it is not a part
of the CFG.

Differential Revision: https://reviews.llvm.org/D129496
2022-07-26 09:07:22 +02:00
Kazu Hirata 3f3930a451 Remove redundaunt virtual specifiers (NFC)
Identified with tidy-modernize-use-override.
2022-07-25 23:00:59 -07:00
Kazu Hirata ae002f8bca Use isa instead of dyn_cast (NFC) 2022-07-25 23:00:58 -07:00
Kazu Hirata 95a932fb15 Remove redundaunt override specifiers (NFC)
Identified with modernize-use-override.
2022-07-24 22:28:11 -07:00
Denys Petrov a364987368 [analyzer][NFC] Use `SValVisitor` instead of explicit helper functions
Summary: Get rid of explicit function splitting in favor of specifically designed Visitor. Move logic from a family of `evalCastKind` and `evalCastSubKind` helper functions to `SValVisitor`.

Differential Revision: https://reviews.llvm.org/D130029
2022-07-19 23:10:00 +03:00
serge-sans-paille f764dc99b3 [clang] Introduce -fstrict-flex-arrays=<n> for stricter handling of flexible arrays
Some code [0] consider that trailing arrays are flexible, whatever their size.
Support for these legacy code has been introduced in
f8f6324983 but it prevents evaluation of
__builtin_object_size and __builtin_dynamic_object_size in some legit cases.

Introduce -fstrict-flex-arrays=<n> to have stricter conformance when it is
desirable.

n = 0: current behavior, any trailing array member is a flexible array. The default.
n = 1: any trailing array member of undefined, 0 or 1 size is a flexible array member
n = 2: any trailing array member of undefined or 0 size is a flexible array member

This takes into account two specificities of clang: array bounds as macro id
disqualify FAM, as well as non standard layout.

Similar patch for gcc discuss here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836

[0] https://docs.freebsd.org/en/books/developers-handbook/sockets/#sockets-essential-functions
2022-07-18 12:45:52 +02:00
Denys Petrov bc08c3cb7f [analyzer] Add new function `clang_analyzer_value` to ExprInspectionChecker
Summary: Introduce a new function 'clang_analyzer_value'. It emits a report that in turn prints a RangeSet or APSInt associated with SVal. If there is no associated value, prints "n/a".
2022-07-15 20:07:04 +03:00
Denys Petrov 82f76c0477 [analyzer][NFC] Tidy up handler-functions in SymbolicRangeInferrer
Summary: Sorted some handler-functions into more appropriate visitor functions of the SymbolicRangeInferrer.
- Spread `getRangeForNegatedSub` body over several visitor functions: `VisitSymExpr`, `VisitSymIntExpr`, `VisitSymSymExpr`.
- Moved `getRangeForComparisonSymbol` from `infer` to `VisitSymSymExpr`.

Differential Revision: https://reviews.llvm.org/D129678
2022-07-15 19:24:57 +03:00
Fangrui Song 3c849d0aef Modernize Optional::{getValueOr,hasValue} 2022-07-15 01:20:39 -07:00
isuckatcs b032e3ff61 [analyzer] Evaluate construction of non-POD type arrays
Introducing the support for evaluating the constructor
of every element in an array. The idea is to record the
index of the current array member being constructed and
create a loop during the analysis. We looping over the
same CXXConstructExpr as many times as many elements
the array has.

Differential Revision: https://reviews.llvm.org/D127973
2022-07-14 23:30:21 +02:00
Ella Ma 32fe1a4be9 [analyzer] Fixing SVal::getType returns Null Type for NonLoc::ConcreteInt in boolean type
In method `TypeRetrievingVisitor::VisitConcreteInt`, `ASTContext::getIntTypeForBitwidth` is used to get the type for `ConcreteInt`s.
However, the getter in ASTContext cannot handle the boolean type with the bit width of 1, which will make method `SVal::getType` return a Null `Type`.
In this patch, a check for this case is added to fix this problem by returning the bool type directly when the bit width is 1.

Differential Revision: https://reviews.llvm.org/D129737
2022-07-14 22:00:38 +08:00
Kazu Hirata cb2c8f694d [clang] Use value instead of getValue (NFC) 2022-07-13 23:39:33 -07:00
Kazu Hirata 53daa177f8 [clang, clang-tools-extra] Use has_value instead of hasValue (NFC) 2022-07-12 22:47:41 -07:00
Gabor Marton 2df120784a [analyzer] Fix assertion in simplifySymbolCast
Depends on D128068.
Added a new test code that fails an assertion in the baseline.
That is because `getAPSIntType` works only with integral types.

Differential Revision: https://reviews.llvm.org/D126779
2022-07-05 19:00:23 +02:00
Gabor Marton 5d7fa481cf [analyzer] Do not emit redundant SymbolCasts
In `RegionStore::getBinding` we call `evalCast` unconditionally to align
the stored value's type to the one that is being queried. However, the
stored type might be the same, so we may end up having redundant
`SymbolCasts` emitted.

The solution is to check whether the `to` and `from` type are the same
in `makeNonLoc`.

Note, we can't just do type equivalence check at the beginning of `evalCast`
because when `evalCast` is called from `getBinding` then the original type
(`OriginalTy`) is not set, so one operand is missing for the comparison. In
`evalCastSubKind(nonloc::SymbolVal)` when the original type is not set,
we get the `from` type via `SymbolVal::getType()`.

Differential Revision: https://reviews.llvm.org/D128068
2022-07-05 18:42:34 +02:00
Fazlay Rabbi 38bcd483dd [OpenMP] Initial parsing and semantic support for 'parallel masked taskloop simd' construct
This patch gives basic parsing and semantic support for
"parallel masked taskloop simd" construct introduced in
OpenMP 5.1 (section 2.16.10)

Differential Revision: https://reviews.llvm.org/D128946
2022-07-01 08:57:15 -07:00
Fazlay Rabbi d64ba896d3 [OpenMP] Initial parsing and sema support for 'parallel masked taskloop' construct
This patch gives basic parsing and semantic support for
"parallel masked taskloop" construct introduced in
OpenMP 5.1 (section 2.16.9)

Differential Revision: https://reviews.llvm.org/D128834
2022-06-30 11:44:17 -07:00
isuckatcs 9d2e830737 [analyzer] Fix BindingDecl evaluation for reference types
The case when the bound variable is reference type in a
BindingDecl wasn't handled, which lead to false positives.

Differential Revision: https://reviews.llvm.org/D128716
2022-06-29 13:01:19 +02:00
Fazlay Rabbi 73e5d7bdff [OpenMP] Initial parsing and sema support for 'masked taskloop simd' construct
This patch gives basic parsing and semantic support for
"masked taskloop simd" construct introduced in OpenMP 5.1 (section 2.16.8)

Differential Revision: https://reviews.llvm.org/D128693
2022-06-28 15:27:49 -07:00
Vitaly Buka cdfa15da94 Revert "[clang] Introduce -fstrict-flex-arrays=<n> for stricter handling of flexible arrays"
This reverts D126864 and related fixes.

This reverts commit 572b08790a.
This reverts commit 886715af96.
2022-06-27 14:03:09 -07:00
Kazu Hirata 97afce08cb [clang] Don't use Optional::hasValue (NFC)
This patch replaces Optional::hasValue with the implicit cast to bool
in conditionals only.
2022-06-25 22:26:24 -07:00
Kazu Hirata 3b7c3a654c Revert "Don't use Optional::hasValue (NFC)"
This reverts commit aa8feeefd3.
2022-06-25 11:56:50 -07:00
Kazu Hirata aa8feeefd3 Don't use Optional::hasValue (NFC) 2022-06-25 11:55:57 -07:00
Fazlay Rabbi 42bb88e2aa [OpenMP] Initial parsing and sema support for 'masked taskloop' construct
This patch gives basic parsing and semantic support for "masked taskloop"
construct introduced in OpenMP 5.1 (section 2.16.7)

Differential Revision: https://reviews.llvm.org/D128478
2022-06-24 10:00:08 -07:00
serge-sans-paille 886715af96 [clang] Introduce -fstrict-flex-arrays=<n> for stricter handling of flexible arrays
Some code [0] consider that trailing arrays are flexible, whatever their size.
Support for these legacy code has been introduced in
f8f6324983 but it prevents evaluation of
__builtin_object_size and __builtin_dynamic_object_size in some legit cases.

Introduce -fstrict-flex-arrays=<n> to have stricter conformance when it is
desirable.

n = 0: current behavior, any trailing array member is a flexible array. The default.
n = 1: any trailing array member of undefined, 0 or 1 size is a flexible array member
n = 2: any trailing array member of undefined or 0 size is a flexible array member
n = 3: any trailing array member of undefined size is a flexible array member (strict c99 conformance)

Similar patch for gcc discuss here: https://gcc.gnu.org/bugzilla/show_bug.cgi?id=101836

[0] https://docs.freebsd.org/en/books/developers-handbook/sockets/#sockets-essential-functions
2022-06-24 16:13:29 +02:00
isuckatcs 8ef628088b [analyzer] Structured binding to arrays
Introducing structured binding to data members and more.
To handle binding to arrays, ArrayInitLoopExpr is also
evaluated, which enables the analyzer to store information
in two more cases. These are:
  - when a lambda-expression captures an array by value
  - in the implicit copy/move constructor for a class
    with an array member

Differential Revision: https://reviews.llvm.org/D126613
2022-06-23 11:38:21 +02:00
Kazu Hirata ca4af13e48 [clang] Don't use Optional::getValue (NFC) 2022-06-20 22:59:26 -07:00
Kazu Hirata 0916d96d12 Don't use Optional::hasValue (NFC) 2022-06-20 20:17:57 -07:00
Kazu Hirata 064a08cd95 Don't use Optional::hasValue (NFC) 2022-06-20 20:05:16 -07:00
Kazu Hirata 5413bf1bac Don't use Optional::hasValue (NFC) 2022-06-20 11:33:56 -07:00
Kazu Hirata 452db157c9 [clang] Don't use Optional::hasValue (NFC) 2022-06-20 10:51:34 -07:00
Kazu Hirata 06decd0b41 [clang] Use value_or instead of getValueOr (NFC) 2022-06-18 23:21:34 -07:00
isuckatcs e77ac66b8c [Static Analyzer] Structured binding to data members
Introducing structured binding to data members.

Differential Revision: https://reviews.llvm.org/D127643
2022-06-17 19:50:10 +02:00
isuckatcs 92bf652d40 [Static Analyzer] Small array binding policy
If a lazyCompoundVal to a struct is bound to the store, there is a policy which decides
whether a copy gets created instead.

This patch introduces a similar policy for arrays, which is required to model structured
binding to arrays without false negatives.

Differential Revision: https://reviews.llvm.org/D128064
2022-06-17 18:56:13 +02:00
Jennifer Yu bb83f8e70b [OpenMP] Initial parsing and sema for 'parallel masked' construct
Differential Revision: https://reviews.llvm.org/D127454
2022-06-16 18:01:15 -07:00
Balazs Benics 929e60b6bd [analyzer] Relax constraints on const qualified regions
The arithmetic restriction seems to be artificial.
The comment below seems to be stale.
Thus, we remove both.

Depends on D127306.

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D127763
2022-06-15 17:08:27 +02:00
Balazs Benics f4fc3f6ba3 [analyzer] Treat system globals as mutable if they are not const
Previously, system globals were treated as immutable regions, unless it
was the `errno` which is known to be frequently modified.

D124244 wants to add a check for stores to immutable regions.
It would basically turn all stores to system globals into an error even
though we have no reason to believe that those mutable sys globals
should be treated as if they were immutable. And this leads to
false-positives if we apply D124244.

In this patch, I'm proposing to treat mutable sys globals actually
mutable, hence allocate them into the `GlobalSystemSpaceRegion`, UNLESS
they were declared as `const` (and a primitive arithmetic type), in
which case, we should use `GlobalImmutableSpaceRegion`.

In any other cases, I'm using the `GlobalInternalSpaceRegion`, which is
no different than the previous behavior.

---

In the tests I added, only the last `expected-warning` was different, compared to the baseline.
Which is this:
```lang=C++
void test_my_mutable_system_global_constraint() {
  assert(my_mutable_system_global > 2);
  clang_analyzer_eval(my_mutable_system_global > 2); // expected-warning {{TRUE}}
  invalidate_globals();
  clang_analyzer_eval(my_mutable_system_global > 2); // expected-warning {{UNKNOWN}} It was previously TRUE.
}
void test_my_mutable_system_global_assign(int x) {
  my_mutable_system_global = x;
  clang_analyzer_eval(my_mutable_system_global == x); // expected-warning {{TRUE}}
  invalidate_globals();
  clang_analyzer_eval(my_mutable_system_global == x); // expected-warning {{UNKNOWN}} It was previously TRUE.
}
```

---

Unfortunately, the taint checker will be also affected.
The `stdin` global variable is a pointer, which is assumed to be a taint
source, and the rest of the taint propagation rules will propagate from
it.
However, since mutable variables are no longer treated immutable, they
also get invalidated, when an opaque function call happens, such as the
first `scanf(stdin, ...)`. This would effectively remove taint from the
pointer, consequently disable all the rest of the taint propagations
down the line from the `stdin` variable.

All that said, I decided to look through `DerivedSymbol`s as well, to
acquire the memregion in that case as well. This should preserve the
previously existing taint reports.

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D127306
2022-06-15 17:08:27 +02:00
Balazs Benics 96ccb690a0 [analyzer][NFC] Prefer using isa<> instead getAs<> in conditions
Depends on D125709

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D127742
2022-06-15 16:58:13 +02:00
Balazs Benics f1b18a79b7 [analyzer][NFC] Remove dead code and modernize surroundings
Thanks @kazu for helping me clean these parts in D127799.

I'm leaving the dump methods, along with the unused visitor handlers and
the forwarding methods.

The dead parts actually helped to uncover two bugs, to which I'm going
to post separate patches.

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D127836
2022-06-15 16:50:12 +02:00
Balazs Benics 40940fb2a6 [analyzer][NFC] Substitute the SVal::evalMinus and evalComplement functions
Depends on D126127

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D127734
2022-06-14 18:56:43 +02:00
Balazs Benics cfc915149c [analyzer][NFC] Relocate unary transfer functions
This is an initial step of removing the SimpleSValBuilder abstraction. The SValBuilder alone should be enough.

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D126127
2022-06-14 18:56:43 +02:00
Kazu Hirata f5ef2c5838 [clang] Convert for_each to range-based for loops (NFC) 2022-06-10 22:39:45 -07:00
Balazs Benics b73c2280f5 [analyzer][NFC] Remove unused RegionStoreFeatures
Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D126216
2022-06-10 13:02:26 +02:00
Balazs Benics 07a7fd314a [analyzer] Print the offending function at EndAnalysis crash
I've faced crashes in the past multiple times when some
`check::EndAnalysis` callback caused some crash.
It's really anoying that it doesn't tell which function triggered this
callback.

This patch adds the well-known trace for that situation as well.
Example:
  1.      <eof> parser at end of file
  2.      While analyzing stack:
          #0 Calling test11

Note that this does not have tests.
I've considered `unittests` for this purpose, by using the
`ASSERT_DEATH()` similarly how we check double eval called functions in
`ConflictingEvalCallsTest.cpp`, however, that the testsuite won't invoke
the custom handlers. Only the message of the `llvm_unreachable()` will
be printed. Consequently, it's not applicable for us testing this
feature.

I've also considered using an end-to-end LIT test for this.
For that, we would need to somehow overload the `clang_analyzer_crash()`
`ExprInspection` handler, to get triggered by other events than the
`EvalCall`. I'm not saying that we could not come up with a generic way
of causing crash in a specific checker callback, but I'm not sure if
that would worth the effort.

Reviewed By: martong

Differential Revision: https://reviews.llvm.org/D127389
2022-06-10 12:21:17 +02:00
Gabor Marton bc2c759aee [analyzer] Fix assertion failure after getKnownValue call
Depends on D126560. `getKnownValue` has been changed by the parent patch
in a way that simplification was removed. This is not correct when the
function is called by the Checkers. Thus, a new internal function is
introduced, `getConstValue`, which simply queries the constraint manager.
This `getConstValue` is used internally in the `SimpleSValBuilder` when a
binop is evaluated, this way we avoid the recursion into the `Simplifier`.

Differential Revision: https://reviews.llvm.org/D127285
2022-06-09 16:13:57 +02:00
Gabor Marton 8131ee4c43 [analyzer] Remove NotifyAssumeClients
Depends on D126560.

Differential Revision: https://reviews.llvm.org/D126878
2022-06-07 13:02:03 +02:00
Gabor Marton 17e9ea6138 [analyzer][NFC] Add LLVM_UNLIKELY to assumeDualImpl
Aligned with the measures we had in D124674, this condition seems to be
unlikely.

Nevertheless, I've made some new measurments with stats just for this,
and data confirms this is indeed unlikely.

Differential Revision: https://reviews.llvm.org/D127190
2022-06-07 12:48:48 +02:00
Gabor Marton f66f4d3b07 [analyzer] Track assume call stack to detect fixpoint
Assume functions might recurse (see `reAssume` or `tryRearrange`).
During the recursion, the State might not change anymore, that means we
reached a fixpoint. In this patch, we avoid infinite recursion of assume
calls by checking already visited States on the stack of assume function
calls. This patch renders the previous "workaround" solution (D47155)
unnecessary. Note that this is not an NFC patch. If we were to limit the
maximum stack depth of the assume calls to 1 then would it be equivalent
with the previous solution in D47155.

Additionally, in D113753, we simplify the symbols right at the beginning
of evalBinOpNN. So, a call to `simplifySVal` in `getKnownValue` (added
in D51252) is no longer needed.

Fixes https://github.com/llvm/llvm-project/issues/55851

Differential Revision: https://reviews.llvm.org/D126560
2022-06-07 08:36:11 +02:00
Kazu Hirata e0039b8d6a Use llvm::less_second (NFC) 2022-06-04 22:48:32 -07:00