cling/patches/llvm_dynlib_reshuffle.diff

Index: include/llvm/Support/DynamicLibrary.h
===================================================================
--- include/llvm/Support/DynamicLibrary.h	(revision 167609)
+++ include/llvm/Support/DynamicLibrary.h	(working copy)
@@ -91,6 +91,13 @@ namespace sys {
       return SearchForAddressOfSymbol(symbolName.c_str());
     }
 
+    /// This function will search through all previously loaded dynamic
+    /// libraries for the symbol \p symbolName, but not through explicitly
+    /// provided symbols (AddSymbol()). If it is found, the address of
+    /// that symbol is returned. If not, null is returned.
+    /// @brief Search through libraries for address of a symbol
+    static void *SearchForLibrarySymbol(const char *SymbolName);
+
     /// This functions permanently adds the symbol \p symbolName with the
     /// value \p symbolValue.  These symbols are searched before any
     /// libraries.
Index: lib/Support/Unix/DynamicLibrary.inc
===================================================================
--- lib/Support/Unix/DynamicLibrary.inc	(revision 0)
+++ lib/Support/Unix/DynamicLibrary.inc	(revision 0)
@@ -0,0 +1,118 @@
+//===--- Unix/DynamicLibrary.cpp - Unix DL Implementation -------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file provides the dlsym specific implementation of DynamicLibrary.
+//
+//===----------------------------------------------------------------------===//
+
+#include <dlfcn.h>
+
+static void MakeDlErrMsg(std::string *ErrMsg) {
+  if (ErrMsg) {
+    *ErrMsg = dlerror();
+  } else {
+    // Flush error state whether or not ErrMsg is provided.
+    dlerror();
+  }
+}
+
+void *OpenLibraryImpl(const char *Filename, std::string *ErrMsg) {
+  void *Handle = dlopen(Filename, RTLD_LAZY|RTLD_GLOBAL);
+  if (Handle == 0) {
+    MakeDlErrMsg(ErrMsg);
+    return NULL;
+  }
+
+#ifdef __CYGWIN__
+  // Cygwin searches symbols only in the main
+  // with the handle of dlopen(NULL, RTLD_GLOBAL).
+  if (Filename == NULL)
+    Handle = RTLD_DEFAULT;
+#endif
+  return Handle;
+}
+
+bool CloseLibraryImpl(void *DlHandle, std::string *ErrMsg) {
+  if (dlclose(DlHandle)) {
+    MakeDlErrMsg(ErrMsg);
+    return false;
+  }
+  return true;
+}
+
+void *GetAddressOfSymbolImpl(void *DlHandle, const char *SymbolName,
+                             bool /*Global*/) {
+  return dlsym(DlHandle, SymbolName);
+}
+
+#include <string.h>
+
+// Must declare the symbols in the global namespace.
+void PopulateSpecialSymbolsImpl(StringMap<void *>& SymMap) {
+// This macro returns the address of a well-known, explicit symbol
+#define EXPLICIT_SYMBOL(SYM) \
+    SymMap[#SYM] = &SYM
+
+// On linux we have a weird situation. The stderr/out/in symbols are both
+// macros and global variables because of standards requirements. So, we
+// boldly use the EXPLICIT_SYMBOL macro without checking for a #define first.
+#if defined(__linux__) and !defined(__ANDROID__)
+  {
+    EXPLICIT_SYMBOL(stderr);
+    EXPLICIT_SYMBOL(stdout);
+    EXPLICIT_SYMBOL(stdin);
+  }
+#else
+  // For everything else, we want to check to make sure the symbol isn't defined
+  // as a macro before using EXPLICIT_SYMBOL.
+  {
+#ifndef stdin
+    EXPLICIT_SYMBOL(stdin);
+#endif
+#ifndef stdout
+    EXPLICIT_SYMBOL(stdout);
+#endif
+#ifndef stderr
+    EXPLICIT_SYMBOL(stderr);
+#endif
+  }
+#endif
+#undef EXPLICIT_SYMBOL
+
+#define EXPLICIT_SYMBOL(SYM) \
+   extern "C" void *SYM; symMap[#SYM] = &SYM
+
+  // If this is darwin, it has some funky issues, try to solve them here.  Some
+  // important symbols are marked 'private external' which doesn't allow
+  // SearchForAddressOfSymbol to find them.  As such, we special case them here,
+  // there is only a small handful of them.
+
+#ifdef __APPLE__
+  {
+    // __eprintf is sometimes used for assert() handling on x86.
+    //
+    // FIXME: Currently disabled when using Clang, as we don't always have our
+    // runtime support libraries available.
+#ifndef __clang__
+#ifdef __i386__
+    EXPLICIT_SYMBOL(__eprintf);
+#endif
+#endif
+  }
+#endif
+
+#ifdef __CYGWIN__
+  {
+    EXPLICIT_SYMBOL(_alloca);
+    EXPLICIT_SYMBOL(__main);
+  }
+#endif
+
+#undef EXPLICIT_SYMBOL
+}
Index: lib/Support/DynamicLibrary.cpp
===================================================================
--- lib/Support/DynamicLibrary.cpp	(revision 167609)
+++ lib/Support/DynamicLibrary.cpp	(working copy)
@@ -9,7 +9,7 @@
 //
 //  This header file implements the operating system DynamicLibrary concept.
 //
-// FIXME: This file leaks ExplicitSymbols and OpenedHandles!
+// FIXME: This file leaks OpenedHandles!
 //
 //===----------------------------------------------------------------------===//
 
@@ -21,11 +21,45 @@
 #include <cstdio>
 #include <cstring>
 
-// Collection of symbol name/value pairs to be searched prior to any libraries.
-static llvm::StringMap<void *> *ExplicitSymbols = 0;
+using namespace llvm;
+using namespace llvm::sys;
+ 
+// Platform-specific implementations are required to define these function.
+// They do not need to be reentrant; locking is done by the caller.
 
+// Open the shared library called filename and return its handle. If filename
+// is NULL, return a handle for searching symbols in the whole process.
+static void *OpenLibraryImpl(const char *Filename, std::string *ErrMsg);
+// Close the shared library.
+static bool  CloseLibraryImpl(void *DlHandle, std::string *ErrMsg);
+// Get the address of the symbol named symname from the library with dlhandle.
+// Global is true if this is part of a search spanning all OpenedHandles.
+static void *GetAddressOfSymbolImpl(void *DlHandle, const char *SymbolName,
+                                    bool Global);
+// Inject special platform symbols into the map of explicitly defined symbols.
+static void PopulateSpecialSymbolsImpl(StringMap<void *>& SymMap);
+
 namespace {
 
+struct SpecialSymbolHolder {
+  SpecialSymbolHolder() {
+    PopulateSpecialSymbolsImpl(Map);
+  }
+ 
+  // Symbol name/value pairs to be searched prior to any libraries.
+  StringMap<void *> Map;
+};
+
+}
+
+// Platform specific symbols, searched after libraries
+static SpecialSymbolHolder *SpecialSymbols = 0;
+
+// User provided symbols, searched before libraries
+static StringMap<void *> *ExplicitSymbols = 0;
+
+namespace {
+
 struct ExplicitSymbolsDeleter {
   ~ExplicitSymbolsDeleter() {
     delete ExplicitSymbols;
@@ -42,148 +76,98 @@ static llvm::sys::SmartMutex<true>& getMutex() {
   return HandlesMutex;
 }
 
-void llvm::sys::DynamicLibrary::AddSymbol(StringRef symbolName,
-                                          void *symbolValue) {
-  SmartScopedLock<true> lock(getMutex());
-  if (ExplicitSymbols == 0)
-    ExplicitSymbols = new llvm::StringMap<void*>();
-  (*ExplicitSymbols)[symbolName] = symbolValue;
-}
-
 char llvm::sys::DynamicLibrary::Invalid = 0;
 
-#ifdef LLVM_ON_WIN32
+static DenseSet<void *> *OpenedHandles;
 
-#include "Windows/DynamicLibrary.inc"
-
-#else
-
-#if HAVE_DLFCN_H
-#include <dlfcn.h>
-using namespace llvm;
-using namespace llvm::sys;
-
-//===----------------------------------------------------------------------===//
-//=== WARNING: Implementation here must contain only TRULY operating system
-//===          independent code.
-//===----------------------------------------------------------------------===//
-
-static DenseSet<void *> *OpenedHandles = 0;
-
-DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename,
-                                                   std::string *errMsg) {
+DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *Filename,
+                                                   std::string *ErrMsg) {
   SmartScopedLock<true> lock(getMutex());
 
-  void *handle = dlopen(filename, RTLD_LAZY|RTLD_GLOBAL);
-  if (handle == 0) {
-    if (errMsg) *errMsg = dlerror();
+  void *Handle = OpenLibraryImpl(Filename, ErrMsg);
+  if (Handle == 0) {
     return DynamicLibrary();
   }
-
-#ifdef __CYGWIN__
-  // Cygwin searches symbols only in the main
-  // with the handle of dlopen(NULL, RTLD_GLOBAL).
-  if (filename == NULL)
-    handle = RTLD_DEFAULT;
-#endif
-
   if (OpenedHandles == 0)
     OpenedHandles = new DenseSet<void *>();
 
   // If we've already loaded this library, dlclose() the handle in order to
   // keep the internal refcount at +1.
-  if (!OpenedHandles->insert(handle).second)
-    dlclose(handle);
+  if (!OpenedHandles->insert(Handle).second)
+    CloseLibraryImpl(Handle, 0);
 
-  return DynamicLibrary(handle);
-}
+  return DynamicLibrary(Handle);
+}  
 
-void *DynamicLibrary::getAddressOfSymbol(const char *symbolName) {
-  if (!isValid())
-    return NULL;
-  return dlsym(Data, symbolName);
+void llvm::sys::DynamicLibrary::AddSymbol(StringRef SymbolName,
+                                          void *SymbolValue) {
+  SmartScopedLock<true> lock(getMutex());
+  if (ExplicitSymbols == 0)
+    ExplicitSymbols = new StringMap<void *>();
+  (*ExplicitSymbols)[SymbolName] = SymbolValue;
 }
 
-#else
-
-using namespace llvm;
-using namespace llvm::sys;
-
-DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename,
-                                                   std::string *errMsg) {
-  if (errMsg) *errMsg = "dlopen() not supported on this platform";
-  return DynamicLibrary();
+void *DynamicLibrary::getAddressOfSymbol(const char *SymbolName) {
+  return GetAddressOfSymbolImpl(Data, SymbolName, false /*Global*/);
 }
 
-void *DynamicLibrary::getAddressOfSymbol(const char *symbolName) {
+void *DynamicLibrary::SearchForLibrarySymbol(const char *SymbolName) {
+  if (OpenedHandles) {
+    for (DenseSet<void *>::iterator I = OpenedHandles->begin(),
+         E = OpenedHandles->end(); I != E; ++I) {
+      void *ptr = GetAddressOfSymbolImpl(*I, SymbolName, true /*Global*/);
+      if (ptr) {
+        return ptr;
+      }
+    }
+  }
   return NULL;
 }
 
-#endif
-
-namespace llvm {
-void *SearchForAddressOfSpecialSymbol(const char* symbolName);
-}
-
-void* DynamicLibrary::SearchForAddressOfSymbol(const char *symbolName) {
+void* DynamicLibrary::SearchForAddressOfSymbol(const char *SymbolName) {
   SmartScopedLock<true> Lock(getMutex());
 
   // First check symbols added via AddSymbol().
   if (ExplicitSymbols) {
-    StringMap<void *>::iterator i = ExplicitSymbols->find(symbolName);
+    StringMap<void *>::iterator i = ExplicitSymbols->find(SymbolName);
 
     if (i != ExplicitSymbols->end())
       return i->second;
   }
 
-#if HAVE_DLFCN_H
   // Now search the libraries.
-  if (OpenedHandles) {
-    for (DenseSet<void *>::iterator I = OpenedHandles->begin(),
-         E = OpenedHandles->end(); I != E; ++I) {
-      //lt_ptr ptr = lt_dlsym(*I, symbolName);
-      void *ptr = dlsym(*I, symbolName);
-      if (ptr) {
-        return ptr;
-      }
-    }
-  }
-#endif
+  if (void *ptr = SearchForLibrarySymbol(SymbolName))
+    return ptr;
 
-  if (void *Result = llvm::SearchForAddressOfSpecialSymbol(symbolName))
-    return Result;
+  // Finally check platform specific symbols.
+  if (SpecialSymbols) {
+    StringMap<void *>::iterator i = SpecialSymbols->Map.find(SymbolName);
 
-// This macro returns the address of a well-known, explicit symbol
-#define EXPLICIT_SYMBOL(SYM) \
-   if (!strcmp(symbolName, #SYM)) return &SYM
-
-// On linux we have a weird situation. The stderr/out/in symbols are both
-// macros and global variables because of standards requirements. So, we
-// boldly use the EXPLICIT_SYMBOL macro without checking for a #define first.
-#if defined(__linux__) and !defined(__ANDROID__)
-  {
-    EXPLICIT_SYMBOL(stderr);
-    EXPLICIT_SYMBOL(stdout);
-    EXPLICIT_SYMBOL(stdin);
+    if (i != SpecialSymbols->Map.end())
+      return i->second;
   }
-#else
-  // For everything else, we want to check to make sure the symbol isn't defined
-  // as a macro before using EXPLICIT_SYMBOL.
-  {
-#ifndef stdin
-    EXPLICIT_SYMBOL(stdin);
-#endif
-#ifndef stdout
-    EXPLICIT_SYMBOL(stdout);
-#endif
-#ifndef stderr
-    EXPLICIT_SYMBOL(stderr);
-#endif
-  }
-#endif
-#undef EXPLICIT_SYMBOL
 
   return 0;
 }
 
+#ifdef LLVM_ON_WIN32
+#include "Windows/DynamicLibrary.inc"
+#elif HAVE_DLFCN_H
+#include "Unix/DynamicLibrary.inc"
+#else
+
+void *OpenLibraryImpl(const char *, std::string *errMsg) {
+  if (errMsg) *errMsg = "dlopen() not supported on this platform";
+  return NULL;
+ }
+bool CloseLibraryImpl(void *, std::string *ErrMsg) {
+  if (errMsg) *errMsg = "dlclose() not supported on this platform";
+  retun false;
+}
+void *GetAddressOfSymbolImpl(void *, const char *, bool) {
+  return NULL;
+}
+void PopulateSpecialSymbolsImpl(StringMap<void *>&) {
+}
+ 
 #endif // LLVM_ON_WIN32
Index: lib/Support/Windows/DynamicLibrary.inc
===================================================================
--- lib/Support/Windows/DynamicLibrary.inc	(revision 167609)
+++ lib/Support/Windows/DynamicLibrary.inc	(working copy)
@@ -31,16 +31,8 @@
  #pragma comment(lib, "dbghelp.lib")
 #endif
 
-namespace llvm {
-using namespace sys;
+using namespace llvm;
 
-//===----------------------------------------------------------------------===//
-//=== WARNING: Implementation here must contain only Win32 specific code
-//===          and must not be UNIX code.
-//===----------------------------------------------------------------------===//
-
-static DenseSet<HMODULE> *OpenedHandles;
-
 extern "C" {
 
   static BOOL CALLBACK ELM_Callback(WIN32_ELMCB_PCSTR ModuleName,
@@ -63,49 +55,61 @@ extern "C" {
 #endif
         stricmp(ModuleName, "msvcrt20") != 0 &&
         stricmp(ModuleName, "msvcrt40") != 0) {
-      OpenedHandles->insert((HMODULE)ModuleBase);
+       OpenedHandles->insert((HMODULE)ModuleBase);
     }
     return TRUE;
   }
-}
+} // extern "C"
 
-DynamicLibrary DynamicLibrary::getPermanentLibrary(const char *filename,
-                                                   std::string *errMsg) {
-  SmartScopedLock<true> lock(getMutex());
-
-  if (!filename) {
+void *OpenLibraryImpl(const char *Filename, std::string *ErrMsg) {
+  if (!Filename) {
     // When no file is specified, enumerate all DLLs and EXEs in the process.
     if (OpenedHandles == 0)
-      OpenedHandles = new DenseSet<HMODULE>();
+      OpenedHandles = new DenseSet<void *>();
 
     EnumerateLoadedModules(GetCurrentProcess(), ELM_Callback, 0);
     // Dummy library that represents "search all handles".
     // This is mostly to ensure that the return value still shows up as "valid".
-    return DynamicLibrary(&OpenedHandles);
+    return &OpenedHandles;
   }
   
-  HMODULE a_handle = LoadLibrary(filename);
+  HMODULE a_handle = LoadLibrary(Filename);
 
   if (a_handle == 0) {
-    MakeErrMsg(errMsg, std::string(filename) + ": Can't open : ");
-    return DynamicLibrary();
+    MakeErrMsg(ErrMsg, std::string(Filename) + ": Can't open : ");
+    return NULL;
   }
 
-  if (OpenedHandles == 0)
-    OpenedHandles = new DenseSet<HMODULE>();
+  return (void *)a_handle;
+}
 
-  // If we've already loaded this library, FreeLibrary() the handle in order to
-  // keep the internal refcount at +1.
-  if (!OpenedHandles->insert(a_handle).second)
-    FreeLibrary(a_handle);
+bool CloseLibraryImpl(void *DlHandle, std::string *ErrMsg) {
+  if (!FreeLibrary((HMODULE)DlHandle)) {
+    MakeErrMsg(ErrMsg, "Cannot free DLL: ");
+    return false;
+  }
+  return true;
+}
 
-  return DynamicLibrary(a_handle);
+void *GetAddressOfSymbolImpl(void *DlHandle, const char *SymbolName,
+                             bool Global) {
+  if (DlHandle == &OpenedHandles) {
+    // Dummy library that represents "search all handles".
+    if (Global) {
+      // All libraries are already being searched, do not recurse.
+      return 0;
+    } else {
+      // Perform a global symbol search through all libraries.
+      DynamicLibrary::SearchForLibrarySymbol(SymbolName);
+    }
+  }
+  return (void *)(intptr_t) GetProcAddress((HMODULE)DlHandle, SymbolName);
 }
 
 // Stack probing routines are in the support library (e.g. libgcc), but we don't
 // have dynamic linking on windows. Provide a hook.
 #define EXPLICIT_SYMBOL(SYM)                    \
-  extern "C" { extern void *SYM; }
+  extern "C" void *SYM;
 #define EXPLICIT_SYMBOL2(SYMFROM, SYMTO) EXPLICIT_SYMBOL(SYMTO)
 
 #include "explicit_symbols.inc"
@@ -113,51 +117,13 @@ extern "C" {
 #undef EXPLICIT_SYMBOL
 #undef EXPLICIT_SYMBOL2
 
-void* DynamicLibrary::SearchForAddressOfSymbol(const char* symbolName) {
-  SmartScopedLock<true> Lock(getMutex());
+void PopulateSpecialSymbolsImpl(StringMap<void *>& SymMap) {
+#define EXPLICIT_SYMBOL(SYM)                    \
+  SymMap[#SYM] = &SYM;
+#define EXPLICIT_SYMBOL2(SYMFROM, SYMTO) EXPLICIT_SYMBOL(SYMTO)
 
-  // First check symbols added via AddSymbol().
-  if (ExplicitSymbols) {
-    StringMap<void *>::iterator i = ExplicitSymbols->find(symbolName);
+#include "explicit_symbols.inc"
 
-    if (i != ExplicitSymbols->end())
-      return i->second;
-  }
-
-  // Now search the libraries.
-  if (OpenedHandles) {
-    for (DenseSet<HMODULE>::iterator I = OpenedHandles->begin(),
-         E = OpenedHandles->end(); I != E; ++I) {
-      FARPROC ptr = GetProcAddress((HMODULE)*I, symbolName);
-      if (ptr) {
-        return (void *)(intptr_t)ptr;
-      }
-    }
-  }
-
-  #define EXPLICIT_SYMBOL(SYM)                    \
-    if (!strcmp(symbolName, #SYM)) return (void*)&SYM;
-  #define EXPLICIT_SYMBOL2(SYMFROM, SYMTO)        \
-    if (!strcmp(symbolName, #SYMFROM)) return (void*)&SYMTO;
-
-  {
-    #include "explicit_symbols.inc"
-  }
-
-  #undef EXPLICIT_SYMBOL
-  #undef EXPLICIT_SYMBOL2
-
-  return 0;
+#undef EXPLICIT_SYMBOL
+#undef EXPLICIT_SYMBOL2
 }
-
-
-void *DynamicLibrary::getAddressOfSymbol(const char *symbolName) {
-  if (!isValid())
-    return NULL;
-  if (Data == &OpenedHandles)
-    return SearchForAddressOfSymbol(symbolName);
-  return (void *)(intptr_t)GetProcAddress((HMODULE)Data, symbolName);
-}
-
-
-}
Index: lib/Support/CMakeLists.txt
===================================================================
--- lib/Support/CMakeLists.txt	(revision 167609)
+++ lib/Support/CMakeLists.txt	(working copy)
@@ -80,6 +80,7 @@ add_llvm_library(LLVMSupport
   Threading.cpp
   TimeValue.cpp
   Valgrind.cpp
+  Unix/DynamicLibrary.inc
   Unix/Host.inc
   Unix/Memory.inc
   Unix/Mutex.inc
Index: lib/Support/SearchForAddressOfSpecialSymbol.cpp
===================================================================
--- lib/Support/SearchForAddressOfSpecialSymbol.cpp	(revision 167609)
+++ lib/Support/SearchForAddressOfSpecialSymbol.cpp	(working copy)
@@ -1,58 +0,0 @@
-//===- SearchForAddressOfSpecialSymbol.cpp - Function addresses -*- C++ -*-===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-//  This file pulls the addresses of certain symbols out of the linker.  It must
-//  include as few header files as possible because it declares the symbols as
-//  void*, which would conflict with the actual symbol type if any header
-//  declared it.
-//
-//===----------------------------------------------------------------------===//
-
-#include <string.h>
-
-// Must declare the symbols in the global namespace.
-static void *DoSearch(const char* symbolName) {
-#define EXPLICIT_SYMBOL(SYM) \
-   extern void *SYM; if (!strcmp(symbolName, #SYM)) return &SYM
-
-  // If this is darwin, it has some funky issues, try to solve them here.  Some
-  // important symbols are marked 'private external' which doesn't allow
-  // SearchForAddressOfSymbol to find them.  As such, we special case them here,
-  // there is only a small handful of them.
-
-#ifdef __APPLE__
-  {
-    // __eprintf is sometimes used for assert() handling on x86.
-    //
-    // FIXME: Currently disabled when using Clang, as we don't always have our
-    // runtime support libraries available.
-#ifndef __clang__
-#ifdef __i386__
-    EXPLICIT_SYMBOL(__eprintf);
-#endif
-#endif
-  }
-#endif
-
-#ifdef __CYGWIN__
-  {
-    EXPLICIT_SYMBOL(_alloca);
-    EXPLICIT_SYMBOL(__main);
-  }
-#endif
-
-#undef EXPLICIT_SYMBOL
-  return 0;
-}
-
-namespace llvm {
-void *SearchForAddressOfSpecialSymbol(const char* symbolName) {
-  return DoSearch(symbolName);
-}
-}  // namespace llvm