diff --git a/lib/ExecutionEngine/MCJIT/MCJITMemoryManager.h b/lib/ExecutionEngine/MCJIT/MCJITMemoryManager.h
index a68949a..084f9a8 100644
--- a/lib/ExecutionEngine/MCJIT/MCJITMemoryManager.h
+++ b/lib/ExecutionEngine/MCJIT/MCJITMemoryManager.h
@@ -34,12 +34,12 @@
 
   uint8_t *allocateDataSection(uintptr_t Size, unsigned Alignment,
                                unsigned SectionID) {
-    return JMM->allocateSpace(Size, Alignment);
+    return JMM->allocateDataSection(Size, Alignment, SectionID);
   }
 
   uint8_t *allocateCodeSection(uintptr_t Size, unsigned Alignment,
                                unsigned SectionID) {
-    return JMM->allocateSpace(Size, Alignment);
+    return JMM->allocateCodeSection(Size, Alignment, SectionID);
   }
 
   virtual void *getPointerToNamedFunction(const std::string &Name,
diff --git a/tools/lli/lli.cpp b/tools/lli/lli.cpp
index e1759cc..a1cf92e 100644
--- a/tools/lli/lli.cpp
+++ b/tools/lli/lli.cpp
@@ -35,8 +35,20 @@
 #include "llvm/Support/Process.h"
 #include "llvm/Support/Signals.h"
 #include "llvm/Support/TargetSelect.h"
+#include "llvm/Support/DynamicLibrary.h"
+#include "llvm/Support/Memory.h"
 #include <cerrno>
 
+#ifdef __linux__
+// These includes used by LLIMCJITMemoryManager::getPointerToNamedFunction()
+// for Glibc trickery. Look comments in this function for more information.
+#ifdef HAVE_SYS_STAT_H
+#include <sys/stat.h>
+#endif
+#include <fcntl.h>
+#include <unistd.h>
+#endif
+
 #ifdef __CYGWIN__
 #include <cygwin/version.h>
 #if defined(CYGWIN_VERSION_DLL_MAJOR) && CYGWIN_VERSION_DLL_MAJOR<1007
@@ -175,6 +187,191 @@
 #endif
 }
 
+// Memory manager for MCJIT
+class LLIMCJITMemoryManager : public JITMemoryManager {
+public:
+  SmallVector<sys::MemoryBlock, 16> AllocatedDataMem;
+  SmallVector<sys::MemoryBlock, 16> AllocatedCodeMem;
+  SmallVector<sys::MemoryBlock, 16> FreeCodeMem;
+
+  LLIMCJITMemoryManager() { };
+  ~LLIMCJITMemoryManager();
+
+  virtual uint8_t *allocateCodeSection(uintptr_t Size, unsigned Alignment,
+                                       unsigned SectionID);
+
+  virtual uint8_t *allocateDataSection(uintptr_t Size, unsigned Alignment,
+                                       unsigned SectionID);
+
+  virtual void *getPointerToNamedFunction(const std::string &Name,
+                                          bool AbortOnFailure = true);
+
+  // Invalidate instruction cache for code sections. Some platforms with
+  // separate data cache and instruction cache require explicit cache flush,
+  // otherwise JIT code manipulations (like resolved relocations) will get to
+  // the data cache but not to the instruction cache.
+  virtual void invalidateInstructionCache();
+
+  // The MCJITMemoryManager doesn't use the following functions, so we don't
+  // need implement them.
+  virtual void setMemoryWritable() {
+    llvm_unreachable("Unexpected call!");
+  };
+  virtual void setMemoryExecutable() {
+    llvm_unreachable("Unexpected call!");
+  };
+  virtual void setPoisonMemory(bool poison) {
+    llvm_unreachable("Unexpected call!");
+  };
+  virtual void AllocateGOT() {
+    llvm_unreachable("Unexpected call!");
+  };
+  virtual uint8_t *getGOTBase() const {
+    llvm_unreachable("Unexpected call!");
+    return 0;
+  };
+  virtual uint8_t *startFunctionBody(const Function *F,
+                                     uintptr_t &ActualSize){
+    llvm_unreachable("Unexpected call!");
+    return 0;
+  };
+  virtual uint8_t *allocateStub(const GlobalValue* F, unsigned StubSize,
+                                unsigned Alignment) {
+    llvm_unreachable("Unexpected call!");
+    return 0;
+  };
+  virtual void endFunctionBody(const Function *F, uint8_t *FunctionStart,
+                               uint8_t *FunctionEnd) {
+    llvm_unreachable("Unexpected call!");
+  };
+  virtual uint8_t *allocateSpace(intptr_t Size, unsigned Alignment) {
+    llvm_unreachable("Unexpected call!");
+    return 0;
+  };
+  virtual uint8_t *allocateGlobal(uintptr_t Size, unsigned Alignment) {
+    llvm_unreachable("Unexpected call!");
+    return 0;
+  };
+  virtual void deallocateFunctionBody(void *Body) {
+    llvm_unreachable("Unexpected call!");
+  };
+  virtual uint8_t* startExceptionTable(const Function* F,
+                                       uintptr_t &ActualSize) {
+    llvm_unreachable("Unexpected call!");
+    return 0;
+  };
+  virtual void endExceptionTable(const Function *F, uint8_t *TableStart,
+                                 uint8_t *TableEnd, uint8_t* FrameRegister) {
+    llvm_unreachable("Unexpected call!");
+  };
+  virtual void deallocateExceptionTable(void *ET) {
+    llvm_unreachable("Unexpected call!");
+  };
+};
+
+uint8_t *LLIMCJITMemoryManager::allocateDataSection(uintptr_t Size,
+                                                    unsigned Alignment,
+                                                    unsigned SectionID) {
+  if (!Alignment)
+    Alignment = 16;
+  uint8_t *Addr = (uint8_t*)calloc((Size + Alignment - 1)/Alignment, Alignment);
+  AllocatedDataMem.push_back(sys::MemoryBlock(Addr, Size));
+  return Addr;
+}
+
+uint8_t *LLIMCJITMemoryManager::allocateCodeSection(uintptr_t Size,
+                                                    unsigned Alignment,
+                                                    unsigned SectionID) {
+  if (!Alignment)
+    Alignment = 16;
+  unsigned NeedAllocate = Alignment * ((Size + Alignment - 1)/Alignment + 1);
+  uintptr_t Addr = 0;
+  // Look in the list of free code memory regions and use a block there if one
+  // is available.
+  for (int i = 0, e = FreeCodeMem.size(); i != e; ++i) {
+    sys::MemoryBlock &MB = FreeCodeMem[i];
+    if (MB.size() >= NeedAllocate) {
+      Addr = (uintptr_t)MB.base();
+      uintptr_t EndOfBlock = Addr + MB.size();
+      // Align the address.
+      Addr = (Addr + Alignment - 1) & ~(uintptr_t)(Alignment - 1);
+      // Store cutted free memory block.
+      FreeCodeMem[i] = sys::MemoryBlock((void*)(Addr + Size),
+                                        EndOfBlock - Addr - Size);
+      return (uint8_t*)Addr;
+    }
+  }
+
+  // No pre-allocated free block was large enough. Allocate a new memory region.
+  sys::MemoryBlock MB = sys::Memory::AllocateRWX(NeedAllocate, 0, 0);
+
+  AllocatedCodeMem.push_back(MB);
+  Addr = (uintptr_t)MB.base();
+  uintptr_t EndOfBlock = Addr + MB.size();
+  // Align the address.
+  Addr = (Addr + Alignment - 1) & ~(uintptr_t)(Alignment - 1);
+  // The AllocateRWX may allocate much more memory than we need. In this case,
+  // we store the unused memory as a free memory block.
+  unsigned FreeSize = EndOfBlock-Addr-Size;
+  if (FreeSize > 16)
+    FreeCodeMem.push_back(sys::MemoryBlock((void*)(Addr + Size), FreeSize));
+
+  // Return aligned address
+  return (uint8_t*)Addr;
+}
+
+void LLIMCJITMemoryManager::invalidateInstructionCache() {
+  for (int i = 0, e = AllocatedCodeMem.size(); i != e; ++i)
+    sys::Memory::InvalidateInstructionCache(AllocatedCodeMem[i].base(),
+                                            AllocatedCodeMem[i].size());
+}
+
+void *LLIMCJITMemoryManager::getPointerToNamedFunction(const std::string &Name,
+                                                       bool AbortOnFailure) {
+#if defined(__linux__)
+  //===--------------------------------------------------------------------===//
+  // 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 (Name == "stat") return (void*)(intptr_t)&stat;
+  if (Name == "fstat") return (void*)(intptr_t)&fstat;
+  if (Name == "lstat") return (void*)(intptr_t)&lstat;
+  if (Name == "stat64") return (void*)(intptr_t)&stat64;
+  if (Name == "fstat64") return (void*)(intptr_t)&fstat64;
+  if (Name == "lstat64") return (void*)(intptr_t)&lstat64;
+  if (Name == "atexit") return (void*)(intptr_t)&atexit;
+  if (Name == "mknod") return (void*)(intptr_t)&mknod;
+#endif // __linux__
+
+  const char *NameStr = Name.c_str();
+  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;
+  }
+
+  if (AbortOnFailure)
+    report_fatal_error("Program used external function '" + Name +
+                      "' which could not be resolved!");
+  return 0;
+}
+
+LLIMCJITMemoryManager::~LLIMCJITMemoryManager() {
+  for (unsigned i = 0, e = AllocatedCodeMem.size(); i != e; ++i)
+    sys::Memory::ReleaseRWX(AllocatedCodeMem[i]);
+  for (unsigned i = 0, e = AllocatedDataMem.size(); i != e; ++i)
+    free(AllocatedDataMem[i].base());
+}
+
 //===----------------------------------------------------------------------===//
 // main Driver function
 //
@@ -233,8 +430,11 @@
     Mod->setTargetTriple(Triple::normalize(TargetTriple));
 
   // Enable MCJIT if desired.
+  LLIMCJITMemoryManager *JMM = 0;
   if (UseMCJIT && !ForceInterpreter) {
     builder.setUseMCJIT(true);
+    JMM = new LLIMCJITMemoryManager();
+    builder.setJITMemoryManager(JMM);
   }
 
   CodeGenOpt::Level OLvl = CodeGenOpt::Default;
@@ -265,6 +465,10 @@
     exit(1);
   }
 
+  // Clear instruction cache before code will be executed.
+  if (JMM)
+    JMM->invalidateInstructionCache();
+
   // The following functions have no effect if their respective profiling
   // support wasn't enabled in the build configuration.
   EE->RegisterJITEventListener(
diff --git a/tools/llvm-rtdyld/llvm-rtdyld.cpp b/tools/llvm-rtdyld/llvm-rtdyld.cpp
index 01a7d15..95de8d8 100644
--- a/tools/llvm-rtdyld/llvm-rtdyld.cpp
+++ b/tools/llvm-rtdyld/llvm-rtdyld.cpp
@@ -63,18 +63,37 @@
     return 0;
   }
 
+  // Invalidate instruction cache for sections with execute permissions.
+  // Some platforms with separate data cache and instruction cache require
+  // explicit cache flush, otherwise JIT code manipulations (like resolved
+  // relocations) will get to the data cache but not to the instruction cache.
+  virtual void invalidateInstructionCache();
 };
 
 uint8_t *TrivialMemoryManager::allocateCodeSection(uintptr_t Size,
                                                    unsigned Alignment,
                                                    unsigned SectionID) {
-  return (uint8_t*)sys::Memory::AllocateRWX(Size, 0, 0).base();
+  sys::MemoryBlock MB = sys::Memory::AllocateRWX(Size, 0, 0);
+  FunctionMemory.push_back(MB);
+  return (uint8_t*)MB.base();
 }
 
 uint8_t *TrivialMemoryManager::allocateDataSection(uintptr_t Size,
                                                    unsigned Alignment,
                                                    unsigned SectionID) {
-  return (uint8_t*)sys::Memory::AllocateRWX(Size, 0, 0).base();
+  sys::MemoryBlock MB = sys::Memory::AllocateRWX(Size, 0, 0);
+  DataMemory.push_back(MB);
+  return (uint8_t*)MB.base();
+}
+
+void TrivialMemoryManager::invalidateInstructionCache() {
+  for (int i = 0, e = FunctionMemory.size(); i != e; ++i)
+    sys::Memory::InvalidateInstructionCache(FunctionMemory[i].base(),
+                                            FunctionMemory[i].size());
+
+  for (int i = 0, e = DataMemory.size(); i != e; ++i)
+    sys::Memory::InvalidateInstructionCache(DataMemory[i].base(),
+                                            DataMemory[i].size());
 }
 
 static const char *ProgramName;
@@ -113,6 +132,8 @@
 
   // Resolve all the relocations we can.
   Dyld.resolveRelocations();
+  // Clear instruction cache before code will be executed.
+  MemMgr->invalidateInstructionCache();
 
   // FIXME: Error out if there are unresolved relocations.