clang/unittests/StaticAnalyzer/SymbolReaperTest.cpp

   1 //===- unittests/StaticAnalyzer/SymbolReaperTest.cpp ----------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "Reusables.h"
  10
  11 #include "clang/Tooling/Tooling.h"
  12 #include "gtest/gtest.h"
  13
  14 namespace clang {
  15 namespace ento {
  16 namespace {
  17
  18 class SuperRegionLivenessConsumer : public ExprEngineConsumer {
  19   void performTest(const Decl *D) {
  20     const auto *FD = findDeclByName<FieldDecl>(D, "x");
  21     const auto *VD = findDeclByName<VarDecl>(D, "s");
  22     assert(FD && VD);
  23
  24     // The variable must belong to a stack frame,
  25     // otherwise SymbolReaper would think it's a global.
  26     const StackFrameContext *SFC =
  27         Eng.getAnalysisDeclContextManager().getStackFrame(D);
  28
  29     // Create regions for 's' and 's.x'.
  30     const VarRegion *VR = Eng.getRegionManager().getVarRegion(VD, SFC);
  31     const FieldRegion *FR = Eng.getRegionManager().getFieldRegion(FD, VR);
  32
  33     // Pass a null location context to the SymbolReaper so that
  34     // it was thinking that the variable is dead.
  35     SymbolReaper SymReaper((StackFrameContext *)nullptr, (Stmt *)nullptr,
  36                            Eng.getSymbolManager(), Eng.getStoreManager());
  37
  38     SymReaper.markLive(FR);
  39     EXPECT_TRUE(SymReaper.isLiveRegion(VR));
  40   }
  41
  42 public:
  43   SuperRegionLivenessConsumer(CompilerInstance &C) : ExprEngineConsumer(C) {}
  44   ~SuperRegionLivenessConsumer() override {}
  45
  46   bool HandleTopLevelDecl(DeclGroupRef DG) override {
  47     for (const auto *D : DG)
  48       performTest(D);
  49     return true;
  50   }
  51 };
  52
  53 class SuperRegionLivenessAction : public ASTFrontendAction {
  54 public:
  55   SuperRegionLivenessAction() {}
  56   std::unique_ptr<ASTConsumer> CreateASTConsumer(CompilerInstance &Compiler,
  57                                                  StringRef File) override {
  58     return std::make_unique<SuperRegionLivenessConsumer>(Compiler);
  59   }
  60 };
  61
  62 // Test that marking s.x as live would also make s live.
  63 TEST(SymbolReaper, SuperRegionLiveness) {
  64   EXPECT_TRUE(
  65       tooling::runToolOnCode(std::make_unique<SuperRegionLivenessAction>(),
  66                              "void foo() { struct S { int x; } s; }"));
  67 }
  68
  69 } // namespace
  70 } // namespace ento
  71 } // namespace clang