3 files changed, 129 insertions, 0 deletions
diff --git a/llvm/unittests/DebugInfo/PDB/CMakeLists.txt b/llvm/unittests/DebugInfo/PDB/CMakeLists.txt
index 5410e5f895d..842a42b6802 100644
--- a/llvm/unittests/DebugInfo/PDB/CMakeLists.txt
+++ b/llvm/unittests/DebugInfo/PDB/CMakeLists.txt
@@ -6,6 +6,7 @@ set(LLVM_LINK_COMPONENTS
 
 add_llvm_unittest(DebugInfoPDBTests
   HashTableTest.cpp
+  NativeSymbolReuseTest.cpp
   StringTableBuilderTest.cpp
   PDBApiTest.cpp
   )
diff --git a/llvm/unittests/DebugInfo/PDB/Inputs/empty.pdb b/llvm/unittests/DebugInfo/PDB/Inputs/empty.pdb
new file mode 100644
index 00000000000..ae65c3a885c
--- /dev/null
+++ b/llvm/unittests/DebugInfo/PDB/Inputs/empty.pdb
diff --git a/llvm/unittests/DebugInfo/PDB/NativeSymbolReuseTest.cpp b/llvm/unittests/DebugInfo/PDB/NativeSymbolReuseTest.cpp
new file mode 100644
index 00000000000..8c98f837142
--- /dev/null
+++ b/llvm/unittests/DebugInfo/PDB/NativeSymbolReuseTest.cpp
@@ -0,0 +1,128 @@
+//===- NativeSymbolReuseTest.cpp ------------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/DebugInfo/PDB/PDB.h"
+
+#include "llvm/DebugInfo/PDB/IPDBSession.h"
+#include "llvm/DebugInfo/PDB/Native/NativeSession.h"
+#include "llvm/DebugInfo/PDB/PDBSymbolCompiland.h"
+#include "llvm/DebugInfo/PDB/PDBSymbolExe.h"
+#include "llvm/Support/Path.h"
+
+#include "llvm/Testing/Support/Error.h"
+#include "llvm/Testing/Support/SupportHelpers.h"
+
+#include "gtest/gtest.h"
+
+using namespace llvm;
+using namespace llvm::pdb;
+
+TEST(NativeSymbolReuseTest, GlobalSymbolReuse) {
+  SmallString<128> InputsDir = unittest::getInputFileDirectory();
+  llvm::sys::path::append(InputsDir, "empty.pdb");
+
+  std::unique_ptr<IPDBSession> S;
+  Error E = pdb::loadDataForPDB(PDB_ReaderType::Native, InputsDir, S);
+
+  ASSERT_THAT_ERROR(std::move(E), Succeeded());
+
+  SymIndexId GlobalId;
+  {
+    auto GS1 = S->getGlobalScope();
+    auto GS2 = S->getGlobalScope();
+
+    GlobalId = GS1->getSymIndexId();
+    SymIndexId Id2 = GS1->getSymIndexId();
+    EXPECT_EQ(GlobalId, Id2);
+  }
+
+  {
+    auto GS3 = S->getGlobalScope();
+
+    SymIndexId Id3 = GS3->getSymIndexId();
+    EXPECT_EQ(GlobalId, Id3);
+  }
+}
+
+TEST(NativeSymbolReuseTest, CompilandSymbolReuse) {
+  SmallString<128> InputsDir = unittest::getInputFileDirectory();
+  llvm::sys::path::append(InputsDir, "empty.pdb");
+
+  std::unique_ptr<IPDBSession> S;
+  Error E = pdb::loadDataForPDB(PDB_ReaderType::Native, InputsDir, S);
+
+  ASSERT_THAT_ERROR(std::move(E), Succeeded());
+
+  auto GS = S->getGlobalScope();
+
+  std::vector<SymIndexId> CompilandIds;
+  {
+    auto Compilands = GS->findAllChildren<PDBSymbolCompiland>();
+    ASSERT_NE(nullptr, Compilands);
+    ASSERT_EQ(2, Compilands->getChildCount());
+    std::vector<SymIndexId> Ids2;
+
+    // First try resetting the enumerator, then try destroying the enumerator
+    // and constructing another one.
+    while (auto Compiland = Compilands->getNext())
+      CompilandIds.push_back(Compiland->getSymIndexId());
+    Compilands->reset();
+    while (auto Compiland = Compilands->getNext())
+      Ids2.push_back(Compiland->getSymIndexId());
+
+    EXPECT_EQ(CompilandIds, Ids2);
+  }
+
+  {
+    auto Compilands = GS->findAllChildren<PDBSymbolCompiland>();
+    ASSERT_NE(nullptr, Compilands);
+    ASSERT_EQ(2U, Compilands->getChildCount());
+
+    std::vector<SymIndexId> Ids3;
+    while (auto Compiland = Compilands->getNext())
+      Ids3.push_back(Compiland->getSymIndexId());
+
+    EXPECT_EQ(CompilandIds, Ids3);
+  }
+}
+
+TEST(NativeSymbolReuseTest, CompilandSymbolReuseBackwards) {
+  SmallString<128> InputsDir = unittest::getInputFileDirectory();
+  llvm::sys::path::append(InputsDir, "empty.pdb");
+
+  std::unique_ptr<IPDBSession> S;
+  Error E = pdb::loadDataForPDB(PDB_ReaderType::Native, InputsDir, S);
+
+  ASSERT_THAT_ERROR(std::move(E), Succeeded());
+
+  auto GS = S->getGlobalScope();
+
+  // This time do the first iteration backwards, and make sure that when you
+  // then iterate them forwards, the IDs come out in reverse.
+  std::vector<SymIndexId> CompilandIds;
+  {
+    auto Compilands = GS->findAllChildren<PDBSymbolCompiland>();
+    ASSERT_NE(nullptr, Compilands);
+    ASSERT_EQ(2U, Compilands->getChildCount());
+
+    std::vector<SymIndexId> Ids2;
+
+    for (int I = Compilands->getChildCount() - 1; I >= 0; --I) {
+      auto Compiland = Compilands->getChildAtIndex(I);
+      CompilandIds.push_back(Compiland->getSymIndexId());
+    }
+
+    while (auto Compiland = Compilands->getNext())
+      Ids2.push_back(Compiland->getSymIndexId());
+
+    auto ReversedIter = llvm::reverse(Ids2);
+    std::vector<SymIndexId> Reversed{ReversedIter.begin(), ReversedIter.end()};
+    EXPECT_EQ(CompilandIds, Reversed);
+  }
+}