Library-ize the dyld components of llvm-rtdyld.

Move the dynamic linking functionality of the llvm-rtdyld program into an
ExecutionEngine support library. Update llvm-rtdyld to just load an object
file into memory, use the library to process it, then run the _main()
function, if one is found.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@128031 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/ExecutionEngine/RuntimeDyld.h

@@ -0,0 +1,45 @@
+//===-- RuntimeDyld.h - Run-time dynamic linker for MC-JIT ------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// Interface for the runtime dynamic linker facilities of the MC-JIT.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_RUNTIME_DYLD_H
+#define LLVM_RUNTIME_DYLD_H
+
+#include "llvm/ADT/StringRef.h"
+#include "llvm/Support/Memory.h"
+
+namespace llvm {
+
+class RuntimeDyldImpl;
+class MemoryBuffer;
+
+class RuntimeDyld {
+  RuntimeDyld(const RuntimeDyld &);     // DO NOT IMPLEMENT
+  void operator=(const RuntimeDyld &);  // DO NOT IMPLEMENT
+
+  // RuntimeDyldImpl is the actual class. RuntimeDyld is just the public
+  // interface.
+  RuntimeDyldImpl *Dyld;
+public:
+  RuntimeDyld();
+  ~RuntimeDyld();
+
+  bool loadObject(MemoryBuffer *InputBuffer);
+  void *getSymbolAddress(StringRef Name);
+  // FIXME: Should be parameterized to get the memory block associated with
+  // a particular loaded object.
+  sys::MemoryBlock getMemoryBlock();
+};
+
+} // end namespace llvm
+
+#endif