Check in LLVM r95781.
diff --git a/lib/System/Disassembler.cpp b/lib/System/Disassembler.cpp
new file mode 100644
index 0000000..bad427a
--- /dev/null
+++ b/lib/System/Disassembler.cpp
@@ -0,0 +1,79 @@
+//===- lib/System/Disassembler.cpp ------------------------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file 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;
+
+bool llvm::sys::hasDisassembler()
+{
+#if defined (__i386__) || defined (__amd64__) || defined (__x86_64__)
+ // We have option to enable udis86 library.
+# if USE_UDIS86
+ return true;
+#else
+ return false;
+#endif
+#else
+ return false;
+#endif
+}
+
+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 options.\n";
+# endif
+
+#else
+ res << "No disassembler available. See configure help for options.\n";
+#endif
+
+ return res.str();
+}