Moved disassembler to libSystem


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@33461 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/System/Disassembler.cpp b/lib/System/Disassembler.cpp
new file mode 100644
index 0000000..8a01562
--- /dev/null
+++ b/lib/System/Disassembler.cpp
@@ -0,0 +1,65 @@
+//===- lib/System/Disassembler.cpp ------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file was developed by Anton Korobeynikov and is distributed under the
+// University of Illinois Open Source License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the necessary glue to call external disassembler
+// libraries.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/Config/config.h"
+#include "llvm/System/Disassembler.h"
+
+#include <cassert>
+#include <iomanip>
+#include <string>
+#include <sstream>
+
+#if USE_UDIS86
+#include <udis86.h>
+#endif
+
+using namespace llvm;
+
+std::string llvm::sys::disassembleBuffer(uint8_t* start, size_t length,
+                                         uint64_t pc) {
+  std::stringstream res;
+
+#if defined (__i386__) || defined (__amd64__) || defined (__x86_64__)
+  unsigned bits;
+# if defined(__i386__)
+  bits = 32;
+# else
+  bits = 64;
+# endif
+  
+# if USE_UDIS86
+  ud_t ud_obj;
+   
+  ud_init(&ud_obj);
+  ud_set_input_buffer(&ud_obj, start, length);
+  ud_set_mode(&ud_obj, bits);
+  ud_set_pc(&ud_obj, pc);
+  ud_set_syntax(&ud_obj, UD_SYN_ATT);
+  
+  res << std::setbase(16)
+      << std::setw(bits/4);
+  
+  while (ud_disassemble(&ud_obj)) {
+    res << ud_insn_off(&ud_obj) << ":\t" << ud_insn_asm(&ud_obj) << "\n";
+  }
+# else
+  res << "No disassembler available. See configure help for avaiable options.\n";
+# endif
+  
+#else
+  res << "No disassembler available. See configure help for avaiable options.\n";
+#endif
+
+  return res.str();
+}