Author: aaronballman
Date: Thu Jul 26 06:03:16 2018
New Revision: 338024
URL: http://llvm.org/viewvc/llvm-project?rev=338024&view=rev
Log:
Allow thread safety annotation lock upgrading and downgrading.
Patch thanks to Aaron Puchert!
Modified:
cfe/trunk/lib/Analysis/ThreadSafety.cpp
cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp
Modified: cfe/trunk/lib/Analysis/ThreadSafety.cpp
URL:
http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/Analysis/ThreadSafety.cpp?rev=338024&r1=338023&r2=338024&view=diff
==============================================================================
--- cfe/trunk/lib/Analysis/ThreadSafety.cpp (original)
+++ cfe/trunk/lib/Analysis/ThreadSafety.cpp Thu Jul 26 06:03:16 2018
@@ -109,9 +109,7 @@ class FactSet;
/// along with additional information, such as where it was acquired, whether
/// it is exclusive or shared, etc.
///
-/// FIXME: this analysis does not currently support either re-entrant
-/// locking or lock "upgrading" and "downgrading" between exclusive and
-/// shared.
+/// FIXME: this analysis does not currently support re-entrant locking.
class FactEntry : public CapabilityExpr {
private:
/// Exclusive or shared.
@@ -1737,8 +1735,7 @@ void BuildLockset::handleCall(Expr *Exp,
}
}
- for(Attr *Atconst : D->attrs()) {
- auto *At = const_cast<Attr *>(Atconst);
+ for(const Attr *At : D->attrs()) {
switch (At->getKind()) {
// When we encounter a lock function, we need to add the lock to our
// lockset.
@@ -1838,6 +1835,16 @@ void BuildLockset::handleCall(Expr *Exp,
}
}
+ // Remove locks first to allow lock upgrading/downgrading.
+ // FIXME -- should only fully remove if the attribute refers to 'this'.
+ bool Dtor = isa<CXXDestructorDecl>(D);
+ for (const auto &M : ExclusiveLocksToRemove)
+ Analyzer->removeLock(FSet, M, Loc, Dtor, LK_Exclusive, CapDiagKind);
+ for (const auto &M : SharedLocksToRemove)
+ Analyzer->removeLock(FSet, M, Loc, Dtor, LK_Shared, CapDiagKind);
+ for (const auto &M : GenericLocksToRemove)
+ Analyzer->removeLock(FSet, M, Loc, Dtor, LK_Generic, CapDiagKind);
+
// Add locks.
for (const auto &M : ExclusiveLocksToAdd)
Analyzer->addLock(FSet, llvm::make_unique<LockableFactEntry>(
@@ -1864,16 +1871,6 @@ void BuildLockset::handleCall(Expr *Exp,
Scp, MLoc, ExclusiveLocksToAdd, SharedLocksToAdd),
CapDiagKind);
}
-
- // Remove locks.
- // FIXME -- should only fully remove if the attribute refers to 'this'.
- bool Dtor = isa<CXXDestructorDecl>(D);
- for (const auto &M : ExclusiveLocksToRemove)
- Analyzer->removeLock(FSet, M, Loc, Dtor, LK_Exclusive, CapDiagKind);
- for (const auto &M : SharedLocksToRemove)
- Analyzer->removeLock(FSet, M, Loc, Dtor, LK_Shared, CapDiagKind);
- for (const auto &M : GenericLocksToRemove)
- Analyzer->removeLock(FSet, M, Loc, Dtor, LK_Generic, CapDiagKind);
}
/// For unary operations which read and write a variable, we need to
Modified: cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp
URL:
http://llvm.org/viewvc/llvm-project/cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp?rev=338024&r1=338023&r2=338024&view=diff
==============================================================================
--- cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp (original)
+++ cfe/trunk/test/SemaCXX/warn-thread-safety-analysis.cpp Thu Jul 26 06:03:16
2018
@@ -22,8 +22,6 @@
#define SHARED_LOCK_FUNCTION(...)
__attribute__((acquire_shared_capability(__VA_ARGS__)))
#define EXCLUSIVE_TRYLOCK_FUNCTION(...)
__attribute__((try_acquire_capability(__VA_ARGS__)))
#define SHARED_TRYLOCK_FUNCTION(...)
__attribute__((try_acquire_shared_capability(__VA_ARGS__)))
-#define EXCLUSIVE_UNLOCK_FUNCTION(...)
__attribute__((release_capability(__VA_ARGS__)))
-#define SHARED_UNLOCK_FUNCTION(...)
__attribute__((release_shared_capability(__VA_ARGS__)))
#define EXCLUSIVE_LOCKS_REQUIRED(...)
__attribute__((requires_capability(__VA_ARGS__)))
#define SHARED_LOCKS_REQUIRED(...)
__attribute__((requires_shared_capability(__VA_ARGS__)))
#else
@@ -34,11 +32,11 @@
#define SHARED_LOCK_FUNCTION(...)
__attribute__((shared_lock_function(__VA_ARGS__)))
#define EXCLUSIVE_TRYLOCK_FUNCTION(...)
__attribute__((exclusive_trylock_function(__VA_ARGS__)))
#define SHARED_TRYLOCK_FUNCTION(...)
__attribute__((shared_trylock_function(__VA_ARGS__)))
-#define EXCLUSIVE_UNLOCK_FUNCTION(...)
__attribute__((unlock_function(__VA_ARGS__)))
-#define SHARED_UNLOCK_FUNCTION(...)
__attribute__((unlock_function(__VA_ARGS__)))
#define EXCLUSIVE_LOCKS_REQUIRED(...)
__attribute__((exclusive_locks_required(__VA_ARGS__)))
#define SHARED_LOCKS_REQUIRED(...)
__attribute__((shared_locks_required(__VA_ARGS__)))
#endif
+#define EXCLUSIVE_UNLOCK_FUNCTION(...)
__attribute__((release_capability(__VA_ARGS__)))
+#define SHARED_UNLOCK_FUNCTION(...)
__attribute__((release_shared_capability(__VA_ARGS__)))
#define UNLOCK_FUNCTION(...)
__attribute__((unlock_function(__VA_ARGS__)))
#define LOCK_RETURNED(x) __attribute__((lock_returned(x)))
#define LOCKS_EXCLUDED(...)
__attribute__((locks_excluded(__VA_ARGS__)))
@@ -50,10 +48,15 @@ class LOCKABLE Mutex {
void Lock() EXCLUSIVE_LOCK_FUNCTION();
void ReaderLock() SHARED_LOCK_FUNCTION();
void Unlock() UNLOCK_FUNCTION();
+ void ExclusiveUnlock() EXCLUSIVE_UNLOCK_FUNCTION();
+ void ReaderUnlock() SHARED_UNLOCK_FUNCTION();
bool TryLock() EXCLUSIVE_TRYLOCK_FUNCTION(true);
bool ReaderTryLock() SHARED_TRYLOCK_FUNCTION(true);
void LockWhen(const int &cond) EXCLUSIVE_LOCK_FUNCTION();
+ void PromoteShared() SHARED_UNLOCK_FUNCTION() EXCLUSIVE_LOCK_FUNCTION();
+ void DemoteExclusive() EXCLUSIVE_UNLOCK_FUNCTION() SHARED_LOCK_FUNCTION();
+
// for negative capabilities
const Mutex& operator!() const { return *this; }
@@ -704,6 +707,26 @@ void shared_fun_8() {
sls_mu.Unlock();
}
+void shared_fun_9() {
+ sls_mu.Lock();
+ sls_mu.ExclusiveUnlock();
+
+ sls_mu.ReaderLock();
+ sls_mu.ReaderUnlock();
+}
+
+void shared_fun_10() {
+ sls_mu.Lock();
+ sls_mu.DemoteExclusive();
+ sls_mu.ReaderUnlock();
+}
+
+void shared_fun_11() {
+ sls_mu.ReaderLock();
+ sls_mu.PromoteShared();
+ sls_mu.Unlock();
+}
+
void shared_bad_0() {
sls_mu.Lock(); // \
// expected-warning {{mutex 'sls_mu' is acquired exclusively and shared in
the same scope}}
@@ -737,6 +760,32 @@ void shared_bad_2() {
sls_mu.Unlock();
}
+void shared_bad_3() {
+ sls_mu.Lock();
+ sls_mu.ReaderUnlock(); // \
+ // expected-warning {{releasing mutex 'sls_mu' using shared access,
expected exclusive access}}
+}
+
+void shared_bad_4() {
+ sls_mu.ReaderLock();
+ sls_mu.ExclusiveUnlock(); // \
+ // expected-warning {{releasing mutex 'sls_mu' using exclusive access,
expected shared access}}
+}
+
+void shared_bad_5() {
+ sls_mu.Lock();
+ sls_mu.PromoteShared(); // \
+ // expected-warning {{releasing mutex 'sls_mu' using shared access,
expected exclusive access}}
+ sls_mu.ExclusiveUnlock();
+}
+
+void shared_bad_6() {
+ sls_mu.ReaderLock();
+ sls_mu.DemoteExclusive(); // \
+ // expected-warning {{releasing mutex 'sls_mu' using exclusive access,
expected shared access}}
+ sls_mu.ReaderUnlock();
+}
+
// FIXME: Add support for functions (not only methods)
class LRBar {
public:
_______________________________________________
cfe-commits mailing list
cfe-commits@lists.llvm.org
http://lists.llvm.org/cgi-bin/mailman/listinfo/cfe-commits
