Refactor DynamicLibrary so searching for a symbol will have a defined order and

libraries are properly unloaded when llvm_shutdown is called.

Summary:
This was mostly affecting usage of the JIT, where storing the library handles in
a set made iteration unordered/undefined. This lead to disagreement between the
JIT and native code as to what the address and implementation of particularly on
Windows with stdlib functions:

JIT: putenv_s("TEST", "VALUE") // called msvcrt.dll, putenv_s
JIT: getenv("TEST") -> "VALUE" // called msvcrt.dll, getenv
Native: getenv("TEST") -> NULL // called ucrt.dll, getenv

Also fixed is the issue of DynamicLibrary::getPermanentLibrary(0,0) on Windows
not giving priority to the process' symbols as it did on Unix.

Reviewers: chapuni, v.g.vassilev, lhames

Reviewed By: lhames

Subscribers: danalbert, srhines, mgorny, vsk, llvm-commits

Differential Revision: https://reviews.llvm.org/D30107

llvm-svn: 301236

1 files changed, 133 insertions, 0 deletions

diff --git a/llvm/unittests/Support/DynamicLibrary/DynamicLibraryTest.cpp b/llvm/unittests/Support/DynamicLibrary/DynamicLibraryTest.cpp
new file mode 100644
index 00000000000..793cd621d1c
--- /dev/null
+++ b/llvm/unittests/Support/DynamicLibrary/DynamicLibraryTest.cpp
@@ -0,0 +1,133 @@
+//===- llvm/unittest/Support/DynamicLibrary/DynamicLibraryTest.cpp --------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Config/config.h"
+#include "llvm/Support/DynamicLibrary.h"
+#include "llvm/Support/FileSystem.h"
+#include "llvm/Support/ManagedStatic.h"
+#include "llvm/Support/Path.h"
+#include "gtest/gtest.h"
+
+#include "PipSqueak.h"
+#include <string>
+
+using namespace llvm;
+using namespace llvm::sys;
+
+extern "C" PIPSQUEAK_EXPORT const char *TestA() { return "ProcessCall"; }
+
+std::string LibPath() {
+  std::string Path =
+      fs::getMainExecutable("DynamicLibraryTests", (void *)&TestA);
+  llvm::SmallString<256> Buf(path::parent_path(Path));
+  path::append(Buf, "PipSqueak.so");
+  return Buf.str();
+}
+
+#if defined(_WIN32) || (defined(HAVE_DLFCN_H) && defined(HAVE_DLOPEN))
+
+typedef void (*SetStrings)(std::string &GStr, std::string &LStr);
+typedef const char *(*GetString)();
+
+template <class T> static T FuncPtr(void *Ptr) {
+  union {
+    T F;
+    void *P;
+  } Tmp;
+  Tmp.P = Ptr;
+  return Tmp.F;
+}
+template <class T> static void* PtrFunc(T *Func) {
+  union {
+    T *F;
+    void *P;
+  } Tmp;
+  Tmp.F = Func;
+  return Tmp.P;
+}
+
+static const char *OverloadTestA() { return "OverloadCall"; }
+
+std::string StdString(const char *Ptr) { return Ptr ? Ptr : ""; }
+
+TEST(DynamicLibrary, Overload) {
+  {
+    std::string Err;
+    llvm_shutdown_obj Shutdown;
+    DynamicLibrary DL =
+        DynamicLibrary::getPermanentLibrary(LibPath().c_str(), &Err);
+    EXPECT_TRUE(DL.isValid());
+    EXPECT_TRUE(Err.empty());
+
+    GetString GS = FuncPtr<GetString>(DL.getAddressOfSymbol("TestA"));
+    EXPECT_TRUE(GS != nullptr && GS != &TestA);
+    EXPECT_EQ(StdString(GS()), "LibCall");
+
+    GS = FuncPtr<GetString>(DynamicLibrary::SearchForAddressOfSymbol("TestA"));
+    EXPECT_TRUE(GS != nullptr && GS != &TestA);
+    EXPECT_EQ(StdString(GS()), "LibCall");
+
+    DL = DynamicLibrary::getPermanentLibrary(nullptr, &Err);
+    EXPECT_TRUE(DL.isValid());
+    EXPECT_TRUE(Err.empty());
+
+    GS = FuncPtr<GetString>(DynamicLibrary::SearchForAddressOfSymbol("TestA"));
+    EXPECT_TRUE(GS != nullptr && GS == &TestA);
+    EXPECT_EQ(StdString(GS()), "ProcessCall");
+
+    GS = FuncPtr<GetString>(DL.getAddressOfSymbol("TestA"));
+    EXPECT_TRUE(GS != nullptr && GS == &TestA);
+    EXPECT_EQ(StdString(GS()), "ProcessCall");
+
+    DynamicLibrary::AddSymbol("TestA", PtrFunc(&OverloadTestA));
+    GS = FuncPtr<GetString>(DL.getAddressOfSymbol("TestA"));
+    EXPECT_TRUE(GS != nullptr && GS != &OverloadTestA);
+
+    GS = FuncPtr<GetString>(DynamicLibrary::SearchForAddressOfSymbol("TestA"));
+    EXPECT_TRUE(GS != nullptr && GS == &OverloadTestA);
+    EXPECT_EQ(StdString(GS()), "OverloadCall");
+  }
+  EXPECT_TRUE(FuncPtr<GetString>(DynamicLibrary::SearchForAddressOfSymbol(
+                  "TestA")) == nullptr);
+}
+
+TEST(DynamicLibrary, Shutdown) {
+  std::string A, B;
+  {
+    std::string Err;
+    llvm_shutdown_obj Shutdown;
+    DynamicLibrary DL =
+        DynamicLibrary::getPermanentLibrary(LibPath().c_str(), &Err);
+    EXPECT_TRUE(DL.isValid());
+    EXPECT_TRUE(Err.empty());
+
+    SetStrings SS = FuncPtr<SetStrings>(
+        DynamicLibrary::SearchForAddressOfSymbol("SetStrings"));
+    EXPECT_TRUE(SS != nullptr);
+
+    SS(A, B);
+    EXPECT_EQ(B, "Local::Local");
+  }
+  EXPECT_EQ(A, "Global::~Global");
+  EXPECT_EQ(B, "Local::~Local");
+  EXPECT_TRUE(FuncPtr<SetStrings>(DynamicLibrary::SearchForAddressOfSymbol(
+                  "SetStrings")) == nullptr);
+}
+
+#else
+
+TEST(DynamicLibrary, Unsupported) {
+  std::string Err;
+  DynamicLibrary DL =
+      DynamicLibrary::getPermanentLibrary(LibPath().c_str(), &Err);
+  EXPECT_FALSE(DL.isValid());
+  EXPECT_EQ(Err, "dlopen() not supported on this platform");
+}
+
+#endif