lib/Support/Disassembler.cpp

   1 //===- lib/System/Disassembler.cpp ------------------------------*- C++ -*-===//
   2 //
   3 //                     The LLVM Compiler Infrastructure
   4 //
   5 // This file is distributed under the University of Illinois Open Source
   6 // License. See LICENSE.TXT for details.
   7 //
   8 //===----------------------------------------------------------------------===//
   9 //
  10 // This file implements the necessary glue to call external disassembler
  11 // libraries.
  12 //
  13 //===----------------------------------------------------------------------===//
  14
  15 #include "llvm/Config/config.h"
  16 #include "llvm/Support/Disassembler.h"
  17
  18 #include <cassert>
  19 #include <iomanip>
  20 #include <string>
  21 #include <sstream>
  22
  23 #if USE_UDIS86
  24 #include <udis86.h>
  25 #endif
  26
  27 using namespace llvm;
  28
  29 bool llvm::sys::hasDisassembler()
  30 {
  31 #if defined (__i386__) || defined (__amd64__) || defined (__x86_64__)
  32   // We have option to enable udis86 library.
  33 # if USE_UDIS86
  34   return true;
  35 #else
  36   return false;
  37 #endif
  38 #else
  39   return false;
  40 #endif
  41 }
  42
  43 std::string llvm::sys::disassembleBuffer(uint8_t* start, size_t length,
  44                                          uint64_t pc) {
  45   std::stringstream res;
  46
  47 #if (defined (__i386__) || defined (__amd64__) || defined (__x86_64__)) \
  48   && USE_UDIS86
  49   unsigned bits;
  50 # if defined(__i386__)
  51   bits = 32;
  52 # else
  53   bits = 64;
  54 # endif
  55
  56   ud_t ud_obj;
  57
  58   ud_init(&ud_obj);
  59   ud_set_input_buffer(&ud_obj, start, length);
  60   ud_set_mode(&ud_obj, bits);
  61   ud_set_pc(&ud_obj, pc);
  62   ud_set_syntax(&ud_obj, UD_SYN_ATT);
  63
  64   res << std::setbase(16)
  65       << std::setw(bits/4);
  66
  67   while (ud_disassemble(&ud_obj)) {
  68     res << ud_insn_off(&ud_obj) << ":\t" << ud_insn_asm(&ud_obj) << "\n";
  69   }
  70 #else
  71   res << "No disassembler available. See configure help for options.\n";
  72 #endif
  73
  74   return res.str();
  75 }