1 files changed, 71 insertions, 0 deletions
diff --git a/contrib/llvm-project/clang/lib/Analysis/FlowSensitive/Models/ChromiumCheckModel.cpp b/contrib/llvm-project/clang/lib/Analysis/FlowSensitive/Models/ChromiumCheckModel.cpp
new file mode 100644
index 000000000000..f457964fb132
--- /dev/null
+++ b/contrib/llvm-project/clang/lib/Analysis/FlowSensitive/Models/ChromiumCheckModel.cpp
@@ -0,0 +1,71 @@
+//===-- ChromiumCheckModel.cpp ----------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+
+#include "clang/Analysis/FlowSensitive/Models/ChromiumCheckModel.h"
+#include "clang/AST/Decl.h"
+#include "clang/AST/DeclCXX.h"
+#include "llvm/ADT/DenseSet.h"
+
+namespace clang {
+namespace dataflow {
+
+/// Determines whether `D` is one of the methods used to implement Chromium's
+/// `CHECK` macros. Populates `CheckDecls`, if empty.
+bool isCheckLikeMethod(llvm::SmallDenseSet<const CXXMethodDecl *> &CheckDecls,
+                       const CXXMethodDecl &D) {
+  // All of the methods of interest are static, so avoid any lookup for
+  // non-static methods (the common case).
+  if (!D.isStatic())
+    return false;
+
+  if (CheckDecls.empty()) {
+    // Attempt to initialize `CheckDecls` with the methods in class
+    // `CheckError`.
+    const CXXRecordDecl *ParentClass = D.getParent();
+    if (ParentClass == nullptr || !ParentClass->getDeclName().isIdentifier() ||
+        ParentClass->getName() != "CheckError")
+      return false;
+
+    // Check whether namespace is "logging".
+    const auto *N =
+        dyn_cast_or_null<NamespaceDecl>(ParentClass->getDeclContext());
+    if (N == nullptr || !N->getDeclName().isIdentifier() ||
+        N->getName() != "logging")
+      return false;
+
+    // Check whether "logging" is a top-level namespace.
+    if (N->getParent() == nullptr || !N->getParent()->isTranslationUnit())
+      return false;
+
+    for (const CXXMethodDecl *M : ParentClass->methods())
+      if (M->getDeclName().isIdentifier() && M->getName().endswith("Check"))
+        CheckDecls.insert(M);
+  }
+
+  return CheckDecls.contains(&D);
+}
+
+bool ChromiumCheckModel::transfer(const CFGElement *Element, Environment &Env) {
+  auto CS = Element->getAs<CFGStmt>();
+  if (!CS)
+    return false;
+  auto Stmt = CS->getStmt();
+  if (const auto *Call = dyn_cast<CallExpr>(Stmt)) {
+    if (const auto *M = dyn_cast<CXXMethodDecl>(Call->getDirectCallee())) {
+      if (isCheckLikeMethod(CheckDecls, *M)) {
+        // Mark this branch as unreachable.
+        Env.addToFlowCondition(Env.getBoolLiteralValue(false));
+        return true;
+      }
+    }
+  }
+  return false;
+}
+
+} // namespace dataflow
+} // namespace clang