/*

 * Copyright (c) 2008, 2017, Oracle and/or its affiliates. All rights reserved.

 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.

 *

 * This code is free software; you can redistribute it and/or modify it

 * under the terms of the GNU General Public License version 2 only, as

 * published by the Free Software Foundation.

 *

 * This code is distributed in the hope that it will be useful, but WITHOUT

 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or

 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License

 * version 2 for more details (a copy is included in the LICENSE file that

 * accompanied this code).

 *

 * You should have received a copy of the GNU General Public License version

 * 2 along with this work; if not, write to the Free Software Foundation,

 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.

 *

 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA

 * or visit www.oracle.com if you need additional information or have any

 * questions.

 *

 */

#include "precompiled.hpp"

#include "classfile/javaClasses.hpp"

#include "code/codeCache.hpp"

#include "compiler/disassembler.hpp"

#include "gc/shared/cardTableModRefBS.hpp"

#include "gc/shared/collectedHeap.hpp"

#include "memory/resourceArea.hpp"

#include "oops/oop.inline.hpp"

#include "runtime/handles.inline.hpp"

#include "runtime/os.hpp"

#include "runtime/stubCodeGenerator.hpp"

#include "runtime/stubRoutines.hpp"

#include CPU_HEADER(depChecker)

void*       Disassembler::_library               = NULL;

bool        Disassembler::_tried_to_load_library = false;

// This routine is in the shared library:

Disassembler::decode_func_virtual Disassembler::_decode_instructions_virtual = NULL;

Disassembler::decode_func Disassembler::_decode_instructions = NULL;

static const char hsdis_library_name[] = "hsdis-" HOTSPOT_LIB_ARCH;

static const char decode_instructions_virtual_name[] = "decode_instructions_virtual";

static const char decode_instructions_name[] = "decode_instructions";

static bool use_new_version = true;

#define COMMENT_COLUMN  40 LP64_ONLY(+8) /*could be an option*/

#define BYTES_COMMENT   ";..."  /* funky byte display comment */

bool Disassembler::load_library() {

  if (_decode_instructions_virtual != NULL || _decode_instructions != NULL) {

    // Already succeeded.

    return true;

  }

  if (_tried_to_load_library) {

    // Do not try twice.

    // To force retry in debugger: assign _tried_to_load_library=0

    return false;

  }

  // Try to load it.

  char ebuf[1024];

  char buf[JVM_MAXPATHLEN];

  os::jvm_path(buf, sizeof(buf));

  int jvm_offset = -1;

  int lib_offset = -1;

#ifdef STATIC_BUILD

  char* p = strrchr(buf, '/');

  *p = '\0';

  strcat(p, "/lib/");

  lib_offset = jvm_offset = strlen(buf);

#else

  {

    // Match "jvm[^/]*" in jvm_path.

    const char* base = buf;

    const char* p = strrchr(buf, *os::file_separator());

    if (p != NULL) lib_offset = p - base + 1;

    p = strstr(p ? p : base, "jvm");

    if (p != NULL) jvm_offset = p - base;

  }

#endif

  // Find the disassembler shared library.

  // Search for several paths derived from libjvm, in this order:

  // 1. <home>/jre/lib/<arch>/<vm>/libhsdis-<arch>.so  (for compatibility)

  // 2. <home>/jre/lib/<arch>/<vm>/hsdis-<arch>.so

  // 3. <home>/jre/lib/<arch>/hsdis-<arch>.so

  // 4. hsdis-<arch>.so  (using LD_LIBRARY_PATH)

  if (jvm_offset >= 0) {

    // 1. <home>/jre/lib/<arch>/<vm>/libhsdis-<arch>.so

    strcpy(&buf[jvm_offset], hsdis_library_name);

    strcat(&buf[jvm_offset], os::dll_file_extension());

    _library = os::dll_load(buf, ebuf, sizeof ebuf);

    if (_library == NULL && lib_offset >= 0) {

      // 2. <home>/jre/lib/<arch>/<vm>/hsdis-<arch>.so

      strcpy(&buf[lib_offset], hsdis_library_name);

      strcat(&buf[lib_offset], os::dll_file_extension());

      _library = os::dll_load(buf, ebuf, sizeof ebuf);

    }

    if (_library == NULL && lib_offset > 0) {

      // 3. <home>/jre/lib/<arch>/hsdis-<arch>.so

      buf[lib_offset - 1] = '\0';

      const char* p = strrchr(buf, *os::file_separator());

      if (p != NULL) {

        lib_offset = p - buf + 1;

        strcpy(&buf[lib_offset], hsdis_library_name);

        strcat(&buf[lib_offset], os::dll_file_extension());

        _library = os::dll_load(buf, ebuf, sizeof ebuf);

      }

    }

  }

  if (_library == NULL) {

    // 4. hsdis-<arch>.so  (using LD_LIBRARY_PATH)

    strcpy(&buf[0], hsdis_library_name);

    strcat(&buf[0], os::dll_file_extension());

    _library = os::dll_load(buf, ebuf, sizeof ebuf);

  }

  if (_library != NULL) {

    _decode_instructions_virtual = CAST_TO_FN_PTR(Disassembler::decode_func_virtual,

                                          os::dll_lookup(_library, decode_instructions_virtual_name));

  }

  if (_decode_instructions_virtual == NULL) {

    // could not spot in new version, try old version

    _decode_instructions = CAST_TO_FN_PTR(Disassembler::decode_func,

                                          os::dll_lookup(_library, decode_instructions_name));

    use_new_version = false;

  } else {

    use_new_version = true;

  }

  _tried_to_load_library = true;

  if (_decode_instructions_virtual == NULL && _decode_instructions == NULL) {

    tty->print_cr("Could not load %s; %s; %s", buf,

                  ((_library != NULL)

                   ? "entry point is missing"

                   : (WizardMode || PrintMiscellaneous)

                   ? (const char*)ebuf

                   : "library not loadable"),

                  "PrintAssembly is disabled");

    return false;

  }

  // Success.

  tty->print_cr("Loaded disassembler from %s", buf);

  return true;

}

class decode_env {

 private:

  nmethod*      _nm;

  CodeBlob*     _code;

  CodeStrings   _strings;

  outputStream* _output;

  address       _start, _end;

  char          _option_buf[512];

  char          _print_raw;

  bool          _print_pc;

  bool          _print_bytes;

  address       _cur_insn;

  int           _bytes_per_line; // arch-specific formatting option

  static bool match(const char* event, const char* tag) {

    size_t taglen = strlen(tag);

    if (strncmp(event, tag, taglen) != 0)

      return false;

    char delim = event[taglen];

    return delim == '\0' || delim == ' ' || delim == '/' || delim == '=';

  }

  void collect_options(const char* p) {

    if (p == NULL || p[0] == '\0')  return;

    size_t opt_so_far = strlen(_option_buf);

    if (opt_so_far + 1 + strlen(p) + 1 > sizeof(_option_buf))  return;

    char* fillp = &_option_buf[opt_so_far];

    if (opt_so_far > 0) *fillp++ = ',';

    strcat(fillp, p);

    // replace white space by commas:

    char* q = fillp;

    while ((q = strpbrk(q, " \t\n")) != NULL)

      *q++ = ',';

    // Note that multiple PrintAssemblyOptions flags accumulate with \n,

    // which we want to be changed to a comma...

  }

  void print_insn_labels();

  void print_insn_bytes(address pc0, address pc);

  void print_address(address value);

 public:

  decode_env(CodeBlob* code, outputStream* output, CodeStrings c = CodeStrings());

  address decode_instructions(address start, address end);

  void start_insn(address pc) {

    _cur_insn = pc;

    output()->bol();

    print_insn_labels();

  }

  void end_insn(address pc) {

    address pc0 = cur_insn();

    outputStream* st = output();

    if (_print_bytes && pc > pc0)

      print_insn_bytes(pc0, pc);

    if (_nm != NULL) {

      _nm->print_code_comment_on(st, COMMENT_COLUMN, pc0, pc);

      // this calls reloc_string_for which calls oop::print_value_on

    }

    // follow each complete insn by a nice newline

    st->cr();

  }

  address handle_event(const char* event, address arg);

  outputStream* output() { return _output; }

  address cur_insn() { return _cur_insn; }

  const char* options() { return _option_buf; }

};

decode_env::decode_env(CodeBlob* code, outputStream* output, CodeStrings c) {

  memset(this, 0, sizeof(*this)); // Beware, this zeroes bits of fields.

  _output = output ? output : tty;

  _code = code;

  if (code != NULL && code->is_nmethod())

    _nm = (nmethod*) code;

  _strings.copy(c);

  // by default, output pc but not bytes:

  _print_pc       = true;

  _print_bytes    = false;

  _bytes_per_line = Disassembler::pd_instruction_alignment();

  // parse the global option string:

  collect_options(Disassembler::pd_cpu_opts());

  collect_options(PrintAssemblyOptions);

  if (strstr(options(), "hsdis-")) {

    if (strstr(options(), "hsdis-print-raw"))

      _print_raw = (strstr(options(), "xml") ? 2 : 1);

    if (strstr(options(), "hsdis-print-pc"))

      _print_pc = !_print_pc;

    if (strstr(options(), "hsdis-print-bytes"))

      _print_bytes = !_print_bytes;

  }

  if (strstr(options(), "help")) {

    tty->print_cr("PrintAssemblyOptions help:");

    tty->print_cr("  hsdis-print-raw       test plugin by requesting raw output");

    tty->print_cr("  hsdis-print-raw-xml   test plugin by requesting raw xml");

    tty->print_cr("  hsdis-print-pc        turn off PC printing (on by default)");

    tty->print_cr("  hsdis-print-bytes     turn on instruction byte output");

    tty->print_cr("combined options: %s", options());

  }

}

address decode_env::handle_event(const char* event, address arg) {

  if (match(event, "insn")) {

    start_insn(arg);

  } else if (match(event, "/insn")) {

    end_insn(arg);

  } else if (match(event, "addr")) {

    if (arg != NULL) {

      print_address(arg);

      return arg;

    }

  } else if (match(event, "mach")) {

    static char buffer[32] = { 0, };

    if (strcmp(buffer, (const char*)arg) != 0 ||

        strlen((const char*)arg) > sizeof(buffer) - 1) {

      // Only print this when the mach changes

      strncpy(buffer, (const char*)arg, sizeof(buffer) - 1);

      buffer[sizeof(buffer) - 1] = '\0';

      output()->print_cr("[Disassembling for mach='%s']", arg);

    }

  } else if (match(event, "format bytes-per-line")) {

    _bytes_per_line = (int) (intptr_t) arg;

  } else {

    // ignore unrecognized markup

  }

  return NULL;

}

// called by the disassembler to print out jump targets and data addresses

void decode_env::print_address(address adr) {

  outputStream* st = _output;

  if (adr == NULL) {

    st->print("NULL");

    return;

  }

  int small_num = (int)(intptr_t)adr;

  if ((intptr_t)adr == (intptr_t)small_num

      && -1 <= small_num && small_num <= 9) {

    st->print("%d", small_num);

    return;

  }

  if (Universe::is_fully_initialized()) {

    if (StubRoutines::contains(adr)) {

      StubCodeDesc* desc = StubCodeDesc::desc_for(adr);

      if (desc == NULL) {

        desc = StubCodeDesc::desc_for(adr + frame::pc_return_offset);

      }

      if (desc != NULL) {

        st->print("Stub::%s", desc->name());

        if (desc->begin() != adr) {

          st->print(INTX_FORMAT_W(+) " " PTR_FORMAT, adr - desc->begin(), p2i(adr));

        } else if (WizardMode) {

          st->print(" " PTR_FORMAT, p2i(adr));

        }

        return;

      }

      st->print("Stub::<unknown> " PTR_FORMAT, p2i(adr));

      return;

    }

    BarrierSet* bs = Universe::heap()->barrier_set();

    if (bs->is_a(BarrierSet::CardTableModRef) &&

        adr == (address)(barrier_set_cast<CardTableModRefBS>(bs)->byte_map_base)) {

      st->print("word_map_base");

      if (WizardMode) st->print(" " INTPTR_FORMAT, p2i(adr));

      return;

    }

  }

  if (_nm == NULL) {

    // Don't do this for native methods, as the function name will be printed in

    // nmethod::reloc_string_for().

    ResourceMark rm;

    const int buflen = 1024;

    char* buf = NEW_RESOURCE_ARRAY(char, buflen);

    int offset;

    if (os::dll_address_to_function_name(adr, buf, buflen, &offset)) {

      st->print(PTR_FORMAT " = %s",  p2i(adr), buf);

      if (offset != 0) {

        st->print("+%d", offset);

      }

      return;

    }

  }

  // Fall through to a simple (hexadecimal) numeral.

  st->print(PTR_FORMAT, p2i(adr));

}

void decode_env::print_insn_labels() {

  address p = cur_insn();

  outputStream* st = output();

  CodeBlob* cb = _code;

  if (cb != NULL) {

    cb->print_block_comment(st, p);

  }

  _strings.print_block_comment(st, (intptr_t)(p - _start));

  if (_print_pc) {

    st->print("  " PTR_FORMAT ": ", p2i(p));

  }

}

void decode_env::print_insn_bytes(address pc, address pc_limit) {

  outputStream* st = output();

  size_t incr = 1;

  size_t perline = _bytes_per_line;

  if ((size_t) Disassembler::pd_instruction_alignment() >= sizeof(int)

      && !((uintptr_t)pc % sizeof(int))

      && !((uintptr_t)pc_limit % sizeof(int))) {

    incr = sizeof(int);

    if (perline % incr)  perline += incr - (perline % incr);

  }

  while (pc < pc_limit) {

    // tab to the desired column:

    st->move_to(COMMENT_COLUMN);

    address pc0 = pc;

    address pc1 = pc + perline;

    if (pc1 > pc_limit)  pc1 = pc_limit;

    for (; pc < pc1; pc += incr) {

      if (pc == pc0) {

        st->print(BYTES_COMMENT);

      } else if ((uint)(pc - pc0) % sizeof(int) == 0) {

        st->print(" ");         // put out a space on word boundaries

      }

      if (incr == sizeof(int)) {

        st->print("%08x", *(int*)pc);

      } else {

        st->print("%02x", (*pc)&0xFF);

      }

    }

    st->cr();

  }

}

static void* event_to_env(void* env_pv, const char* event, void* arg) {

  decode_env* env = (decode_env*) env_pv;

  return env->handle_event(event, (address) arg);

}

ATTRIBUTE_PRINTF(2, 3)

static int printf_to_env(void* env_pv, const char* format, ...) {

  decode_env* env = (decode_env*) env_pv;

  outputStream* st = env->output();

  size_t flen = strlen(format);

  const char* raw = NULL;

  if (flen == 0)  return 0;

  if (flen == 1 && format[0] == '\n') { st->bol(); return 1; }

  if (flen < 2 ||

      strchr(format, '%') == NULL) {

    raw = format;

  } else if (format[0] == '%' && format[1] == '%' &&

             strchr(format+2, '%') == NULL) {

    // happens a lot on machines with names like %foo

    flen--;

    raw = format+1;

  }

  if (raw != NULL) {

    st->print_raw(raw, (int) flen);

    return (int) flen;

  }

  va_list ap;

  va_start(ap, format);

  julong cnt0 = st->count();

  st->vprint(format, ap);

  julong cnt1 = st->count();

  va_end(ap);

  return (int)(cnt1 - cnt0);

}

address decode_env::decode_instructions(address start, address end) {

  _start = start; _end = end;

  assert(((((intptr_t)start | (intptr_t)end) % Disassembler::pd_instruction_alignment()) == 0), "misaligned insn addr");

  const int show_bytes = false; // for disassembler debugging

  //_version = Disassembler::pd_cpu_version();

  if (!Disassembler::can_decode()) {

    return NULL;

  }

  // decode a series of instructions and return the end of the last instruction

  if (_print_raw) {

    // Print whatever the library wants to print, w/o fancy callbacks.

    // This is mainly for debugging the library itself.

    FILE* out = stdout;

    FILE* xmlout = (_print_raw > 1 ? out : NULL);

    return use_new_version ?

      (address)

      (*Disassembler::_decode_instructions_virtual)((uintptr_t)start, (uintptr_t)end,

                                                    start, end - start,

                                                    NULL, (void*) xmlout,

                                                    NULL, (void*) out,

                                                    options(), 0/*nice new line*/)

      :

      (address)

      (*Disassembler::_decode_instructions)(start, end,

                                            NULL, (void*) xmlout,

                                            NULL, (void*) out,

                                            options());

  }

  return use_new_version ?

    (address)

    (*Disassembler::_decode_instructions_virtual)((uintptr_t)start, (uintptr_t)end,

                                                  start, end - start,

                                                  &event_to_env,  (void*) this,

                                                  &printf_to_env, (void*) this,

                                                  options(), 0/*nice new line*/)

    :

    (address)

    (*Disassembler::_decode_instructions)(start, end,

                                          &event_to_env,  (void*) this,

                                          &printf_to_env, (void*) this,

                                          options());

}

void Disassembler::decode(CodeBlob* cb, outputStream* st) {

  ttyLocker ttyl;

  if (!load_library())  return;

  if (cb->is_nmethod()) {

    decode((nmethod*)cb, st);

    return;

  }

  decode_env env(cb, st);

  env.output()->print_cr("----------------------------------------------------------------------");

  if (cb->is_aot()) {

    env.output()->print("A ");

    if (cb->is_compiled()) {

      CompiledMethod* cm = (CompiledMethod*)cb;

      env.output()->print("%d ",cm->compile_id());

      cm->method()->method_holder()->name()->print_symbol_on(env.output());

      env.output()->print(".");

      cm->method()->name()->print_symbol_on(env.output());

      cm->method()->signature()->print_symbol_on(env.output());

    } else {

      env.output()->print_cr("%s", cb->name());

    }

  } else {

    env.output()->print_cr("%s", cb->name());

  }

  env.output()->print_cr(" at  [" PTR_FORMAT ", " PTR_FORMAT "]  " JLONG_FORMAT " bytes", p2i(cb->code_begin()), p2i(cb->code_end()), ((jlong)(cb->code_end() - cb->code_begin())) * sizeof(unsigned char*));

  env.decode_instructions(cb->code_begin(), cb->code_end());

}

void Disassembler::decode(address start, address end, outputStream* st, CodeStrings c) {

  ttyLocker ttyl;