[clang] [clang][dataflow] Add a lattice to help cache const accessor methods (PR #111006)

[Jan Voung via cfe-commits]

================
@@ -0,0 +1,217 @@
+//===- unittests/Analysis/FlowSensitive/CachedConstAccessorsLatticeTest.cpp ==//
+//
+// 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/CachedConstAccessorsLattice.h"
+
+#include <cassert>
+#include <memory>
+
+#include "clang/AST/Decl.h"
+#include "clang/AST/DeclBase.h"
+#include "clang/AST/DeclCXX.h"
+#include "clang/AST/Expr.h"
+#include "clang/AST/Type.h"
+#include "clang/ASTMatchers/ASTMatchFinder.h"
+#include "clang/ASTMatchers/ASTMatchers.h"
+#include "clang/Analysis/FlowSensitive/DataflowAnalysisContext.h"
+#include "clang/Analysis/FlowSensitive/DataflowLattice.h"
+#include "clang/Analysis/FlowSensitive/NoopLattice.h"
+#include "clang/Analysis/FlowSensitive/StorageLocation.h"
+#include "clang/Analysis/FlowSensitive/Value.h"
+#include "clang/Analysis/FlowSensitive/WatchedLiteralsSolver.h"
+#include "clang/Basic/LLVM.h"
+#include "clang/Testing/TestAST.h"
+#include "gmock/gmock.h"
+#include "gtest/gtest.h"
+
+namespace clang::dataflow {
+namespace {
+
+using ast_matchers::callee;
+using ast_matchers::cxxMemberCallExpr;
+using ast_matchers::functionDecl;
+using ast_matchers::hasName;
+using ast_matchers::match;
+using ast_matchers::selectFirst;
+
+using dataflow::DataflowAnalysisContext;
+using dataflow::Environment;
+using dataflow::LatticeJoinEffect;
+using dataflow::RecordStorageLocation;
+using dataflow::Value;
+using dataflow::WatchedLiteralsSolver;
+
+NamedDecl *lookup(StringRef Name, const DeclContext &DC) {
+  auto Result = DC.lookup(&DC.getParentASTContext().Idents.get(Name));
+  EXPECT_TRUE(Result.isSingleResult()) << Name;
+  return Result.front();
+}
+
+class CachedConstAccessorsLatticeTest : public ::testing::Test {
+protected:
+  using LatticeT = CachedConstAccessorsLattice<NoopLattice>;
+
+  DataflowAnalysisContext DACtx{std::make_unique<WatchedLiteralsSolver>()};
+  Environment Env{DACtx};
+};
+
+// Basic test AST with two const methods (return a value, and return a ref).
+struct CommonTestInputs {
+  CommonTestInputs()
+      : AST(R"cpp(
+    struct S {
+      int *valProperty() const;
+      int &refProperty() const;
----------------
jvoung wrote:

Thanks! Added a test "SameStructValBeforeClearOrDiffAfterClear"

https://github.com/llvm/llvm-project/pull/111006