Based on this discussion: http://lists.cs.uiuc.edu/pipermail/llvm-commits/Week-of-Mon-20120305/138477.html

1. Declare a virtual function getPointerToNamedFunction() in JITMemoryManager
2. Move the implementation of getPointerToNamedFunction() form JIT/MCJIT to DefaultJITMemoryManager.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@153205 91177308-0d34-0410-b5e6-96231b3b80d8

11 files changed, 215 insertions, 329 deletions

diff --git a/include/llvm/ExecutionEngine/JITMemoryManager.h b/include/llvm/ExecutionEngine/JITMemoryManager.h
index 8eb7590a21a..3587e38ea37 100644
--- a/include/llvm/ExecutionEngine/JITMemoryManager.h
+++ b/include/llvm/ExecutionEngine/JITMemoryManager.h
@@ -47,6 +47,17 @@ public:
   /// debugging, and may be turned on by default in debug mode.
   virtual void setPoisonMemory(bool poison) = 0;
 
+  /// getPointerToNamedFunction - This method returns the address of the
+  /// specified function by using the dlsym function call.  As such it is only
+  /// useful for resolving library symbols, not code generated symbols.
+  ///
+  /// If AbortOnFailure is false and no function with the given name is
+  /// found, this function silently returns a null pointer. Otherwise,
+  /// it prints a message to stderr and aborts.
+  ///
+  virtual void *getPointerToNamedFunction(const std::string &Name,
+                                          bool AbortOnFailure = true) = 0;
+
   //===--------------------------------------------------------------------===//
   // Global Offset Table Management
   //===--------------------------------------------------------------------===//
diff --git a/lib/ExecutionEngine/JIT/CMakeLists.txt b/lib/ExecutionEngine/JIT/CMakeLists.txt
index 09728723b7d..52bb38970db 100644
--- a/lib/ExecutionEngine/JIT/CMakeLists.txt
+++ b/lib/ExecutionEngine/JIT/CMakeLists.txt
@@ -2,7 +2,6 @@
 add_definitions(-DENABLE_X86_JIT)
 
 add_llvm_library(LLVMJIT
-  Intercept.cpp
   JIT.cpp
   JITDwarfEmitter.cpp
   JITEmitter.cpp
diff --git a/lib/ExecutionEngine/JIT/Intercept.cpp b/lib/ExecutionEngine/JIT/Intercept.cpp
deleted file mode 100644
index 2251a8e6b07..00000000000
--- a/lib/ExecutionEngine/JIT/Intercept.cpp
+++ /dev/null
@@ -1,162 +0,0 @@
-//===-- Intercept.cpp - System function interception routines -------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// If a function call occurs to an external function, the JIT is designed to use
-// the dynamic loader interface to find a function to call.  This is useful for
-// calling system calls and library functions that are not available in LLVM.
-// Some system calls, however, need to be handled specially.  For this reason,
-// we intercept some of them here and use our own stubs to handle them.
-//
-//===----------------------------------------------------------------------===//
-
-#include "JIT.h"
-#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/DynamicLibrary.h"
-#include "llvm/Config/config.h"
-using namespace llvm;
-
-// AtExitHandlers - List of functions to call when the program exits,
-// registered with the atexit() library function.
-static std::vector<void (*)()> AtExitHandlers;
-
-/// runAtExitHandlers - Run any functions registered by the program's
-/// calls to atexit(3), which we intercept and store in
-/// AtExitHandlers.
-///
-static void runAtExitHandlers() {
-  while (!AtExitHandlers.empty()) {
-    void (*Fn)() = AtExitHandlers.back();
-    AtExitHandlers.pop_back();
-    Fn();
-  }
-}
-
-//===----------------------------------------------------------------------===//
-// Function stubs that are invoked instead of certain library calls
-//===----------------------------------------------------------------------===//
-
-// Force the following functions to be linked in to anything that uses the
-// JIT. This is a hack designed to work around the all-too-clever Glibc
-// strategy of making these functions work differently when inlined vs. when
-// not inlined, and hiding their real definitions in a separate archive file
-// that the dynamic linker can't see. For more info, search for
-// 'libc_nonshared.a' on Google, or read http://llvm.org/PR274.
-#if defined(__linux__)
-#if defined(HAVE_SYS_STAT_H)
-#include <sys/stat.h>
-#endif
-#include <fcntl.h>
-#include <unistd.h>
-/* stat functions are redirecting to __xstat with a version number.  On x86-64
- * linking with libc_nonshared.a and -Wl,--export-dynamic doesn't make 'stat'
- * available as an exported symbol, so we have to add it explicitly.
- */
-namespace {
-class StatSymbols {
-public:
-  StatSymbols() {
-    sys::DynamicLibrary::AddSymbol("stat", (void*)(intptr_t)stat);
-    sys::DynamicLibrary::AddSymbol("fstat", (void*)(intptr_t)fstat);
-    sys::DynamicLibrary::AddSymbol("lstat", (void*)(intptr_t)lstat);
-    sys::DynamicLibrary::AddSymbol("stat64", (void*)(intptr_t)stat64);
-    sys::DynamicLibrary::AddSymbol("\x1stat64", (void*)(intptr_t)stat64);
-    sys::DynamicLibrary::AddSymbol("\x1open64", (void*)(intptr_t)open64);
-    sys::DynamicLibrary::AddSymbol("\x1lseek64", (void*)(intptr_t)lseek64);
-    sys::DynamicLibrary::AddSymbol("fstat64", (void*)(intptr_t)fstat64);
-    sys::DynamicLibrary::AddSymbol("lstat64", (void*)(intptr_t)lstat64);
-    sys::DynamicLibrary::AddSymbol("atexit", (void*)(intptr_t)atexit);
-    sys::DynamicLibrary::AddSymbol("mknod", (void*)(intptr_t)mknod);
-  }
-};
-}
-static StatSymbols initStatSymbols;
-#endif // __linux__
-
-// jit_exit - Used to intercept the "exit" library call.
-static void jit_exit(int Status) {
-  runAtExitHandlers();   // Run atexit handlers...
-  exit(Status);
-}
-
-// jit_atexit - Used to intercept the "atexit" library call.
-static int jit_atexit(void (*Fn)()) {
-  AtExitHandlers.push_back(Fn);    // Take note of atexit handler...
-  return 0;  // Always successful
-}
-
-static int jit_noop() {
-  return 0;
-}
-
-//===----------------------------------------------------------------------===//
-//
-/// getPointerToNamedFunction - This method returns the address of the specified
-/// function by using the dynamic loader interface.  As such it is only useful
-/// for resolving library symbols, not code generated symbols.
-///
-void *JIT::getPointerToNamedFunction(const std::string &Name,
-                                     bool AbortOnFailure) {
-  if (!isSymbolSearchingDisabled()) {
-    // Check to see if this is one of the functions we want to intercept.  Note,
-    // we cast to intptr_t here to silence a -pedantic warning that complains
-    // about casting a function pointer to a normal pointer.
-    if (Name == "exit") return (void*)(intptr_t)&jit_exit;
-    if (Name == "atexit") return (void*)(intptr_t)&jit_atexit;
-
-    // We should not invoke parent's ctors/dtors from generated main()!
-    // On Mingw and Cygwin, the symbol __main is resolved to
-    // callee's(eg. tools/lli) one, to invoke wrong duplicated ctors
-    // (and register wrong callee's dtors with atexit(3)).
-    // We expect ExecutionEngine::runStaticConstructorsDestructors()
-    // is called before ExecutionEngine::runFunctionAsMain() is called.
-    if (Name == "__main") return (void*)(intptr_t)&jit_noop;
-
-    const char *NameStr = Name.c_str();
-    // If this is an asm specifier, skip the sentinal.
-    if (NameStr[0] == 1) ++NameStr;
-
-    // If it's an external function, look it up in the process image...
-    void *Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr);
-    if (Ptr) return Ptr;
-
-    // If it wasn't found and if it starts with an underscore ('_') character,
-    // and has an asm specifier, try again without the underscore.
-    if (Name[0] == 1 && NameStr[0] == '_') {
-      Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr+1);
-      if (Ptr) return Ptr;
-    }
-
-    // Darwin/PPC adds $LDBLStub suffixes to various symbols like printf.  These
-    // are references to hidden visibility symbols that dlsym cannot resolve.
-    // If we have one of these, strip off $LDBLStub and try again.
-#if defined(__APPLE__) && defined(__ppc__)
-    if (Name.size() > 9 && Name[Name.size()-9] == '$' &&
-        memcmp(&Name[Name.size()-8], "LDBLStub", 8) == 0) {
-      // First try turning $LDBLStub into $LDBL128. If that fails, strip it off.
-      // This mirrors logic in libSystemStubs.a.
-      std::string Prefix = std::string(Name.begin(), Name.end()-9);
-      if (void *Ptr = getPointerToNamedFunction(Prefix+"$LDBL128", false))
-        return Ptr;
-      if (void *Ptr = getPointerToNamedFunction(Prefix, false))
-        return Ptr;
-    }
-#endif
-  }
-
-  /// If a LazyFunctionCreator is installed, use it to get/create the function.
-  if (LazyFunctionCreator)
-    if (void *RP = LazyFunctionCreator(Name))
-      return RP;
-
-  if (AbortOnFailure) {
-    report_fatal_error("Program used external function '"+Name+
-                      "' which could not be resolved!");
-  }
-  return 0;
-}
diff --git a/lib/ExecutionEngine/JIT/JIT.cpp b/lib/ExecutionEngine/JIT/JIT.cpp
index f715f6f3a26..16b8ee2c1f6 100644
--- a/lib/ExecutionEngine/JIT/JIT.cpp
+++ b/lib/ExecutionEngine/JIT/JIT.cpp
@@ -23,6 +23,7 @@
 #include "llvm/CodeGen/MachineCodeInfo.h"
 #include "llvm/ExecutionEngine/GenericValue.h"
 #include "llvm/ExecutionEngine/JITEventListener.h"
+#include "llvm/ExecutionEngine/JITMemoryManager.h"
 #include "llvm/Target/TargetData.h"
 #include "llvm/Target/TargetMachine.h"
 #include "llvm/Target/TargetJITInfo.h"
@@ -267,9 +268,9 @@ extern "C" {
 }
 
 JIT::JIT(Module *M, TargetMachine &tm, TargetJITInfo &tji,
-         JITMemoryManager *JMM, bool GVsWithCode)
-  : ExecutionEngine(M), TM(tm), TJI(tji), AllocateGVsWithCode(GVsWithCode),
-    isAlreadyCodeGenerating(false) {
+         JITMemoryManager *jmm, bool GVsWithCode)
+  : ExecutionEngine(M), TM(tm), TJI(tji), JMM(jmm),
+    AllocateGVsWithCode(GVsWithCode), isAlreadyCodeGenerating(false) {
   setTargetData(TM.getTargetData());
 
   jitstate = new JITState(M);
@@ -711,6 +712,27 @@ void *JIT::getPointerToBasicBlock(BasicBlock *BB) {
   }
 }
 
+void *JIT::getPointerToNamedFunction(const std::string &Name,
+                                     bool AbortOnFailure){
+  if (!isSymbolSearchingDisabled()) {
+    void *ptr = JMM->getPointerToNamedFunction(Name, false);
+    if (ptr)
+      return ptr;
+  }
+
+  /// If a LazyFunctionCreator is installed, use it to get/create the function.
+  if (LazyFunctionCreator)
+    if (void *RP = LazyFunctionCreator(Name))
+      return RP;
+
+  if (AbortOnFailure) {
+    report_fatal_error("Program used external function '"+Name+
+                      "' which could not be resolved!");
+  }
+  return 0;
+}
+
+
 /// getOrEmitGlobalVariable - Return the address of the specified global
 /// variable, possibly emitting it to memory if needed.  This is used by the
 /// Emitter.
diff --git a/lib/ExecutionEngine/JIT/JIT.h b/lib/ExecutionEngine/JIT/JIT.h
index 17d33fe8087..c5579815336 100644
--- a/lib/ExecutionEngine/JIT/JIT.h
+++ b/lib/ExecutionEngine/JIT/JIT.h
@@ -58,6 +58,7 @@ class JIT : public ExecutionEngine {
   TargetMachine &TM;       // The current target we are compiling to
   TargetJITInfo &TJI;      // The JITInfo for the target we are compiling to
   JITCodeEmitter *JCE;     // JCE object
+  JITMemoryManager *JMM;
   std::vector<JITEventListener*> EventListeners;
 
   /// AllocateGVsWithCode - Some applications require that global variables and
diff --git a/lib/ExecutionEngine/JIT/JITMemoryManager.cpp b/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
index efd570d7c56..d404d0ccdb3 100644
--- a/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
+++ b/lib/ExecutionEngine/JIT/JITMemoryManager.cpp
@@ -314,6 +314,17 @@ namespace {
     /// should allocate a separate slab.
     static const size_t DefaultSizeThreshold;
 
+    /// getPointerToNamedFunction - This method returns the address of the
+    /// specified function by using the dlsym function call.  As such it is only
+    /// useful for resolving library symbols, not code generated symbols.
+    ///
+    /// If AbortOnFailure is false and no function with the given name is
+    /// found, this function silently returns a null pointer. Otherwise,
+    /// it prints a message to stderr and aborts.
+    ///
+    virtual void *getPointerToNamedFunction(const std::string &Name,
+                                            bool AbortOnFailure = true);
+
     void AllocateGOT();
 
     // Testing methods.
@@ -757,6 +768,148 @@ bool DefaultJITMemoryManager::CheckInvariants(std::string &ErrorStr) {
   return true;
 }
 
+//===----------------------------------------------------------------------===//
+// getPointerToNamedFunction() implementation.
+//===----------------------------------------------------------------------===//
+#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/DynamicLibrary.h"
+#include "llvm/Config/config.h"
+
+// AtExitHandlers - List of functions to call when the program exits,
+// registered with the atexit() library function.
+static std::vector<void (*)()> AtExitHandlers;
+
+/// runAtExitHandlers - Run any functions registered by the program's
+/// calls to atexit(3), which we intercept and store in
+/// AtExitHandlers.
+///
+static void runAtExitHandlers() {
+  while (!AtExitHandlers.empty()) {
+    void (*Fn)() = AtExitHandlers.back();
+    AtExitHandlers.pop_back();
+    Fn();
+  }
+}
+
+//===----------------------------------------------------------------------===//
+// Function stubs that are invoked instead of certain library calls
+//===----------------------------------------------------------------------===//
+
+// Force the following functions to be linked in to anything that uses the
+// JIT. This is a hack designed to work around the all-too-clever Glibc
+// strategy of making these functions work differently when inlined vs. when
+// not inlined, and hiding their real definitions in a separate archive file
+// that the dynamic linker can't see. For more info, search for
+// 'libc_nonshared.a' on Google, or read http://llvm.org/PR274.
+#if defined(__linux__)
+#if defined(HAVE_SYS_STAT_H)
+#include <sys/stat.h>
+#endif
+#include <fcntl.h>
+#include <unistd.h>
+/* stat functions are redirecting to __xstat with a version number.  On x86-64
+ * linking with libc_nonshared.a and -Wl,--export-dynamic doesn't make 'stat'
+ * available as an exported symbol, so we have to add it explicitly.
+ */
+namespace {
+class StatSymbols {
+public:
+  StatSymbols() {
+    sys::DynamicLibrary::AddSymbol("stat", (void*)(intptr_t)stat);
+    sys::DynamicLibrary::AddSymbol("fstat", (void*)(intptr_t)fstat);
+    sys::DynamicLibrary::AddSymbol("lstat", (void*)(intptr_t)lstat);
+    sys::DynamicLibrary::AddSymbol("stat64", (void*)(intptr_t)stat64);
+    sys::DynamicLibrary::AddSymbol("\x1stat64", (void*)(intptr_t)stat64);
+    sys::DynamicLibrary::AddSymbol("\x1open64", (void*)(intptr_t)open64);
+    sys::DynamicLibrary::AddSymbol("\x1lseek64", (void*)(intptr_t)lseek64);
+    sys::DynamicLibrary::AddSymbol("fstat64", (void*)(intptr_t)fstat64);
+    sys::DynamicLibrary::AddSymbol("lstat64", (void*)(intptr_t)lstat64);
+    sys::DynamicLibrary::AddSymbol("atexit", (void*)(intptr_t)atexit);
+    sys::DynamicLibrary::AddSymbol("mknod", (void*)(intptr_t)mknod);
+  }
+};
+}
+static StatSymbols initStatSymbols;
+#endif // __linux__
+
+// jit_exit - Used to intercept the "exit" library call.
+static void jit_exit(int Status) {
+  runAtExitHandlers();   // Run atexit handlers...
+  exit(Status);
+}
+
+// jit_atexit - Used to intercept the "atexit" library call.
+static int jit_atexit(void (*Fn)()) {
+  AtExitHandlers.push_back(Fn);    // Take note of atexit handler...
+  return 0;  // Always successful
+}
+
+static int jit_noop() {
+  return 0;
+}
+
+//===----------------------------------------------------------------------===//
+//
+/// getPointerToNamedFunction - This method returns the address of the specified
+/// function by using the dynamic loader interface.  As such it is only useful
+/// for resolving library symbols, not code generated symbols.
+///
+void *DefaultJITMemoryManager::getPointerToNamedFunction(const std::string &Name,
+                                     bool AbortOnFailure) {
+  // Check to see if this is one of the functions we want to intercept.  Note,
+  // we cast to intptr_t here to silence a -pedantic warning that complains
+  // about casting a function pointer to a normal pointer.
+  if (Name == "exit") return (void*)(intptr_t)&jit_exit;
+  if (Name == "atexit") return (void*)(intptr_t)&jit_atexit;
+
+  // We should not invoke parent's ctors/dtors from generated main()!
+  // On Mingw and Cygwin, the symbol __main is resolved to
+  // callee's(eg. tools/lli) one, to invoke wrong duplicated ctors
+  // (and register wrong callee's dtors with atexit(3)).
+  // We expect ExecutionEngine::runStaticConstructorsDestructors()
+  // is called before ExecutionEngine::runFunctionAsMain() is called.
+  if (Name == "__main") return (void*)(intptr_t)&jit_noop;
+
+  const char *NameStr = Name.c_str();
+  // If this is an asm specifier, skip the sentinal.
+  if (NameStr[0] == 1) ++NameStr;
+
+  // If it's an external function, look it up in the process image...
+  void *Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr);
+  if (Ptr) return Ptr;
+
+  // If it wasn't found and if it starts with an underscore ('_') character,
+  // try again without the underscore.
+  if (NameStr[0] == '_') {
+    Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr+1);
+    if (Ptr) return Ptr;
+  }
+
+  // Darwin/PPC adds $LDBLStub suffixes to various symbols like printf.  These
+  // are references to hidden visibility symbols that dlsym cannot resolve.
+  // If we have one of these, strip off $LDBLStub and try again.
+#if defined(__APPLE__) && defined(__ppc__)
+  if (Name.size() > 9 && Name[Name.size()-9] == '$' &&
+      memcmp(&Name[Name.size()-8], "LDBLStub", 8) == 0) {
+    // First try turning $LDBLStub into $LDBL128. If that fails, strip it off.
+    // This mirrors logic in libSystemStubs.a.
+    std::string Prefix = std::string(Name.begin(), Name.end()-9);
+    if (void *Ptr = getPointerToNamedFunction(Prefix+"$LDBL128", false))
+      return Ptr;
+    if (void *Ptr = getPointerToNamedFunction(Prefix, false))
+      return Ptr;
+  }
+#endif
+
+  if (AbortOnFailure) {
+    report_fatal_error("Program used external function '"+Name+
+                      "' which could not be resolved!");
+  }
+  return 0;
+}
+
+
+
 JITMemoryManager *JITMemoryManager::CreateDefaultMemManager() {
   return new DefaultJITMemoryManager();
 }
diff --git a/lib/ExecutionEngine/MCJIT/CMakeLists.txt b/lib/ExecutionEngine/MCJIT/CMakeLists.txt
index 2c0f8d65194..fef71768b49 100644
--- a/lib/ExecutionEngine/MCJIT/CMakeLists.txt
+++ b/lib/ExecutionEngine/MCJIT/CMakeLists.txt
@@ -1,5 +1,4 @@
 add_llvm_library(LLVMMCJIT
   MCJIT.cpp
   MCJITMemoryManager.cpp
-  Intercept.cpp
   )
diff --git a/lib/ExecutionEngine/MCJIT/Intercept.cpp b/lib/ExecutionEngine/MCJIT/Intercept.cpp
deleted file mode 100644
index f83f4282e01..00000000000
--- a/lib/ExecutionEngine/MCJIT/Intercept.cpp
+++ /dev/null
@@ -1,162 +0,0 @@
-//===-- Intercept.cpp - System function interception routines -------------===//
-//
-//                     The LLVM Compiler Infrastructure
-//
-// This file is distributed under the University of Illinois Open Source
-// License. See LICENSE.TXT for details.
-//
-//===----------------------------------------------------------------------===//
-//
-// If a function call occurs to an external function, the JIT is designed to use
-// the dynamic loader interface to find a function to call.  This is useful for
-// calling system calls and library functions that are not available in LLVM.
-// Some system calls, however, need to be handled specially.  For this reason,
-// we intercept some of them here and use our own stubs to handle them.
-//
-//===----------------------------------------------------------------------===//
-
-#include "MCJIT.h"
-#include "llvm/Support/ErrorHandling.h"
-#include "llvm/Support/DynamicLibrary.h"
-#include "llvm/Config/config.h"
-using namespace llvm;
-
-// AtExitHandlers - List of functions to call when the program exits,
-// registered with the atexit() library function.
-static std::vector<void (*)()> AtExitHandlers;
-
-/// runAtExitHandlers - Run any functions registered by the program's
-/// calls to atexit(3), which we intercept and store in
-/// AtExitHandlers.
-///
-static void runAtExitHandlers() {
-  while (!AtExitHandlers.empty()) {
-    void (*Fn)() = AtExitHandlers.back();
-    AtExitHandlers.pop_back();
-    Fn();
-  }
-}
-
-//===----------------------------------------------------------------------===//
-// Function stubs that are invoked instead of certain library calls
-//===----------------------------------------------------------------------===//
-
-// Force the following functions to be linked in to anything that uses the
-// JIT. This is a hack designed to work around the all-too-clever Glibc
-// strategy of making these functions work differently when inlined vs. when
-// not inlined, and hiding their real definitions in a separate archive file
-// that the dynamic linker can't see. For more info, search for
-// 'libc_nonshared.a' on Google, or read http://llvm.org/PR274.
-#if defined(__linux__)
-#if defined(HAVE_SYS_STAT_H)
-#include <sys/stat.h>
-#endif
-#include <fcntl.h>
-#include <unistd.h>
-/* stat functions are redirecting to __xstat with a version number.  On x86-64
- * linking with libc_nonshared.a and -Wl,--export-dynamic doesn't make 'stat'
- * available as an exported symbol, so we have to add it explicitly.
- */
-namespace {
-class StatSymbols {
-public:
-  StatSymbols() {
-    sys::DynamicLibrary::AddSymbol("stat", (void*)(intptr_t)stat);
-    sys::DynamicLibrary::AddSymbol("fstat", (void*)(intptr_t)fstat);
-    sys::DynamicLibrary::AddSymbol("lstat", (void*)(intptr_t)lstat);
-    sys::DynamicLibrary::AddSymbol("stat64", (void*)(intptr_t)stat64);
-    sys::DynamicLibrary::AddSymbol("\x1stat64", (void*)(intptr_t)stat64);
-    sys::DynamicLibrary::AddSymbol("\x1open64", (void*)(intptr_t)open64);
-    sys::DynamicLibrary::AddSymbol("\x1lseek64", (void*)(intptr_t)lseek64);
-    sys::DynamicLibrary::AddSymbol("fstat64", (void*)(intptr_t)fstat64);
-    sys::DynamicLibrary::AddSymbol("lstat64", (void*)(intptr_t)lstat64);
-    sys::DynamicLibrary::AddSymbol("atexit", (void*)(intptr_t)atexit);
-    sys::DynamicLibrary::AddSymbol("mknod", (void*)(intptr_t)mknod);
-  }
-};
-}
-static StatSymbols initStatSymbols;
-#endif // __linux__
-
-// jit_exit - Used to intercept the "exit" library call.
-static void jit_exit(int Status) {
-  runAtExitHandlers();   // Run atexit handlers...
-  exit(Status);
-}
-
-// jit_atexit - Used to intercept the "atexit" library call.
-static int jit_atexit(void (*Fn)()) {
-  AtExitHandlers.push_back(Fn);    // Take note of atexit handler...
-  return 0;  // Always successful
-}
-
-static int jit_noop() {
-  return 0;
-}
-
-//===----------------------------------------------------------------------===//
-//
-/// getPointerToNamedFunction - This method returns the address of the specified
-/// function by using the dynamic loader interface.  As such it is only useful
-/// for resolving library symbols, not code generated symbols.
-///
-void *MCJIT::getPointerToNamedFunction(const std::string &Name,
-                                       bool AbortOnFailure) {
-  if (!isSymbolSearchingDisabled()) {
-    // Check to see if this is one of the functions we want to intercept.  Note,
-    // we cast to intptr_t here to silence a -pedantic warning that complains
-    // about casting a function pointer to a normal pointer.
-    if (Name == "exit") return (void*)(intptr_t)&jit_exit;
-    if (Name == "atexit") return (void*)(intptr_t)&jit_atexit;
-
-    // We should not invoke parent's ctors/dtors from generated main()!
-    // On Mingw and Cygwin, the symbol __main is resolved to
-    // callee's(eg. tools/lli) one, to invoke wrong duplicated ctors
-    // (and register wrong callee's dtors with atexit(3)).
-    // We expect ExecutionEngine::runStaticConstructorsDestructors()
-    // is called before ExecutionEngine::runFunctionAsMain() is called.
-    if (Name == "__main") return (void*)(intptr_t)&jit_noop;
-
-    const char *NameStr = Name.c_str();
-    // If this is an asm specifier, skip the sentinal.
-    if (NameStr[0] == 1) ++NameStr;
-
-    // If it's an external function, look it up in the process image...
-    void *Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr);
-    if (Ptr) return Ptr;
-
-    // If it wasn't found and if it starts with an underscore ('_') character,
-    // and has an asm specifier, try again without the underscore.
-    if (Name[0] == 1 && NameStr[0] == '_') {
-      Ptr = sys::DynamicLibrary::SearchForAddressOfSymbol(NameStr+1);
-      if (Ptr) return Ptr;
-    }
-
-    // Darwin/PPC adds $LDBLStub suffixes to various symbols like printf.  These
-    // are references to hidden visibility symbols that dlsym cannot resolve.
-    // If we have one of these, strip off $LDBLStub and try again.
-#if defined(__APPLE__) && defined(__ppc__)
-    if (Name.size() > 9 && Name[Name.size()-9] == '$' &&
-        memcmp(&Name[Name.size()-8], "LDBLStub", 8) == 0) {
-      // First try turning $LDBLStub into $LDBL128. If that fails, strip it off.
-      // This mirrors logic in libSystemStubs.a.
-      std::string Prefix = std::string(Name.begin(), Name.end()-9);
-      if (void *Ptr = getPointerToNamedFunction(Prefix+"$LDBL128", false))
-        return Ptr;
-      if (void *Ptr = getPointerToNamedFunction(Prefix, false))
-        return Ptr;
-    }
-#endif
-  }
-
-  /// If a LazyFunctionCreator is installed, use it to get/create the function.
-  if (LazyFunctionCreator)
-    if (void *RP = LazyFunctionCreator(Name))
-      return RP;
-
-  if (AbortOnFailure) {
-    report_fatal_error("Program used external function '"+Name+
-                      "' which could not be resolved!");
-  }
-  return 0;
-}
diff --git a/lib/ExecutionEngine/MCJIT/MCJIT.cpp b/lib/ExecutionEngine/MCJIT/MCJIT.cpp
index 5f93a8d3ca8..cbb23d361dc 100644
--- a/lib/ExecutionEngine/MCJIT/MCJIT.cpp
+++ b/lib/ExecutionEngine/MCJIT/MCJIT.cpp
@@ -215,3 +215,23 @@ GenericValue MCJIT::runFunction(Function *F,
 
   llvm_unreachable("Full-featured argument passing not supported yet!");
 }
+
+void *MCJIT::getPointerToNamedFunction(const std::string &Name,
+                                       bool AbortOnFailure){
+  if (!isSymbolSearchingDisabled()) {
+    void *ptr = MemMgr->getPointerToNamedFunction(Name, false);
+    if (ptr)
+      return ptr;
+  }
+
+  /// If a LazyFunctionCreator is installed, use it to get/create the function.
+  if (LazyFunctionCreator)
+    if (void *RP = LazyFunctionCreator(Name))
+      return RP;
+
+  if (AbortOnFailure) {
+    report_fatal_error("Program used external function '"+Name+
+                      "' which could not be resolved!");
+  }
+  return 0;
+}
diff --git a/lib/ExecutionEngine/MCJIT/MCJIT.h b/lib/ExecutionEngine/MCJIT/MCJIT.h
index 7f4ae77343d..2b3df9884eb 100644
--- a/lib/ExecutionEngine/MCJIT/MCJIT.h
+++ b/lib/ExecutionEngine/MCJIT/MCJIT.h
@@ -67,6 +67,7 @@ public:
   ///
   virtual void *getPointerToNamedFunction(const std::string &Name,
                                           bool AbortOnFailure = true);
+
   /// mapSectionAddress - map a section to its target address space value.
   /// Map the address of a JIT section as returned from the memory manager
   /// to the address in the target process as the running code will see it.
diff --git a/unittests/ExecutionEngine/JIT/JITTest.cpp b/unittests/ExecutionEngine/JIT/JITTest.cpp
index 4d10ee63803..fa52321b32e 100644
--- a/unittests/ExecutionEngine/JIT/JITTest.cpp
+++ b/unittests/ExecutionEngine/JIT/JITTest.cpp
@@ -64,6 +64,10 @@ public:
     : Base(JITMemoryManager::CreateDefaultMemManager()) {
     stubsAllocated = 0;
   }
+  virtual void *getPointerToNamedFunction(const std::string &Name,
+                                          bool AbortOnFailure = true) {
+    return Base->getPointerToNamedFunction(Name, AbortOnFailure);
+  }
 
   virtual void setMemoryWritable() { Base->setMemoryWritable(); }
   virtual void setMemoryExecutable() { Base->setMemoryExecutable(); }