[clang] [clang][analyzer] Improve BlockInCriticalSectionsChecker (PR #80029)

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Endre =?utf-8?q?Fülöp?= <endre.fulop at sigmatechnology.com>,
Endre =?utf-8?q?Fülöp?= <endre.fulop at sigmatechnology.com>
Message-ID:
In-Reply-To: <llvm.org/llvm/llvm-project/pull/80029 at github.com>


================
@@ -20,48 +20,178 @@
 #include "clang/StaticAnalyzer/Core/PathSensitive/CallDescription.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CallEvent.h"
 #include "clang/StaticAnalyzer/Core/PathSensitive/CheckerContext.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramStateTrait.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/ProgramState_Fwd.h"
+#include "clang/StaticAnalyzer/Core/PathSensitive/SVals.h"
+#include "llvm/ADT/STLExtras.h"
+#include "llvm/ADT/SmallString.h"
+#include "llvm/ADT/StringExtras.h"
+
+#include <iterator>
+#include <utility>
+#include <variant>
 
 using namespace clang;
 using namespace ento;
 
 namespace {
+
+struct CritSectionMarker {
+  const Expr *LockExpr{};
+  const MemRegion *LockReg{};
+
+  void Profile(llvm::FoldingSetNodeID &ID) const {
+    ID.Add(LockExpr);
+    ID.Add(LockReg);
+  }
+
+  [[nodiscard]] constexpr bool
+  operator==(const CritSectionMarker &Other) const noexcept {
+    return LockExpr == Other.LockExpr && LockReg == Other.LockReg;
+  }
+  [[nodiscard]] constexpr bool
+  operator!=(const CritSectionMarker &Other) const noexcept {
+    return !(*this == Other);
+  }
+};
+
+class CallDescriptionBasedMatcher {
+  CallDescription LockFn;
+  CallDescription UnlockFn;
+
+public:
+  CallDescriptionBasedMatcher(CallDescription &&LockFn,
+                              CallDescription &&UnlockFn)
+      : LockFn(std::move(LockFn)), UnlockFn(std::move(UnlockFn)) {}
+  [[nodiscard]] bool matches(const CallEvent &Call, bool IsLock) const {
+    if (IsLock) {
+      return LockFn.matches(Call);
+    }
+    return UnlockFn.matches(Call);
+  }
+};
+
+class FirstArgMutexDescriptor : public CallDescriptionBasedMatcher {
+public:
+  FirstArgMutexDescriptor(CallDescription &&LockFn, CallDescription &&UnlockFn)
+      : CallDescriptionBasedMatcher(std::move(LockFn), std::move(UnlockFn)) {}
+
+  [[nodiscard]] const MemRegion *getRegion(const CallEvent &Call, bool) const {
+    return Call.getArgSVal(0).getAsRegion();
+  }
+};
+
+class MemberMutexDescriptor : public CallDescriptionBasedMatcher {
+public:
+  MemberMutexDescriptor(CallDescription &&LockFn, CallDescription &&UnlockFn)
+      : CallDescriptionBasedMatcher(std::move(LockFn), std::move(UnlockFn)) {}
+
+  [[nodiscard]] const MemRegion *getRegion(const CallEvent &Call, bool) const {
+    return cast<CXXMemberCall>(Call).getCXXThisVal().getAsRegion();
+  }
+};
+
+class RAIIMutexDescriptor {
+  mutable const IdentifierInfo *Guard{};
+  mutable bool IdentifierInfoInitialized{};
+  mutable llvm::SmallString<32> GuardName{};
+
+  void initIdentifierInfo(const CallEvent &Call) const {
+    if (!IdentifierInfoInitialized) {
+      // In case of checking C code, or when the corresponding headers are not
+      // included, we might end up query the identifier table every time when
+      // this function is called instead of early returning it. To avoid this, a
+      // bool variable (IdentifierInfoInitialized) is used and the function will
+      // be run only once.
+      Guard = &Call.getCalleeAnalysisDeclContext()->getASTContext().Idents.get(
+          GuardName);
+      IdentifierInfoInitialized = true;
+    }
+  }
+
+  template <typename T> bool matchesImpl(const CallEvent &Call) const {
+    const T *C = dyn_cast<T>(&Call);
+    if (!C)
+      return false;
+    const IdentifierInfo *II =
+        cast<CXXRecordDecl>(C->getDecl()->getParent())->getIdentifier();
+    return II == Guard;
+  }
+
+public:
+  RAIIMutexDescriptor(StringRef GuardName) : GuardName(GuardName) {}
+  [[nodiscard]] bool matches(const CallEvent &Call, bool IsLock) const {
+    initIdentifierInfo(Call);
+    if (IsLock) {
+      return matchesImpl<CXXConstructorCall>(Call);
+    }
----------------
NagyDonat wrote:

```suggestion
    if (IsLock)
      return matchesImpl<CXXConstructorCall>(Call);
```
Bikeshedding as above.

https://github.com/llvm/llvm-project/pull/80029