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: 301562

1 files changed, 36 insertions, 0 deletions

diff --git a/llvm/unittests/Support/DynamicLibrary/PipSqueak.cxx b/llvm/unittests/Support/DynamicLibrary/PipSqueak.cxx
new file mode 100644
index 00000000000..1de85236a88
--- /dev/null
+++ b/llvm/unittests/Support/DynamicLibrary/PipSqueak.cxx
@@ -0,0 +1,36 @@
+//===- llvm/unittest/Support/DynamicLibrary/PipSqueak.cxx -----------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+
+#include "PipSqueak.h"
+#include <string>
+
+struct Global {
+  std::string *Str;
+  Global() : Str(nullptr) {}
+  ~Global() {
+    if (Str)
+      *Str = "Global::~Global";
+  }
+};
+
+struct Local {
+  std::string &Str;
+  Local(std::string &S) : Str(S) { Str = "Local::Local"; }
+  ~Local() { Str = "Local::~Local"; }
+};
+
+static Global Glb;
+
+extern "C" PIPSQUEAK_EXPORT void SetStrings(std::string &GStr,
+                                            std::string &LStr) {
+  static Local Lcl(LStr);
+  Glb.Str = &GStr;
+}
+
+extern "C" PIPSQUEAK_EXPORT const char *TestA() { return "LibCall"; }