/*

 * Copyright (c) 2011, 2019, 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 "jfr/recorder/checkpoint/jfrCheckpointWriter.hpp"

#include "jfr/recorder/checkpoint/types/traceid/jfrTraceId.inline.hpp"

#include "jfr/recorder/repository/jfrChunkWriter.hpp"

#include "jfr/recorder/stacktrace/jfrStackTrace.hpp"

#include "memory/allocation.inline.hpp"

#include "runtime/vframe.inline.hpp"

static void copy_frames(JfrStackFrame** lhs_frames, u4 length, const JfrStackFrame* rhs_frames) {

  assert(lhs_frames != NULL, "invariant");

  assert(rhs_frames != NULL, "invariant");

  if (length > 0) {

    *lhs_frames = NEW_C_HEAP_ARRAY(JfrStackFrame, length, mtTracing);

    memcpy(*lhs_frames, rhs_frames, length * sizeof(JfrStackFrame));

  }

}

JfrStackFrame::JfrStackFrame(const traceid& id, int bci, int type, const Method* method) :

  _method(method), _methodid(id), _line(0), _bci(bci), _type(type) {}

JfrStackFrame::JfrStackFrame(const traceid& id, int bci, int type, int lineno) :

  _method(NULL), _methodid(id), _line(lineno), _bci(bci), _type(type) {}

JfrStackTrace::JfrStackTrace(JfrStackFrame* frames, u4 max_frames) :

  _next(NULL),

  _frames(frames),

  _id(0),

  _hash(0),

  _nr_of_frames(0),

  _max_frames(max_frames),

  _frames_ownership(false),

  _reached_root(false),

  _lineno(false),

  _written(false) {}

JfrStackTrace::JfrStackTrace(traceid id, const JfrStackTrace& trace, const JfrStackTrace* next) :

  _next(next),

  _frames(NULL),

  _id(id),

  _hash(trace._hash),

  _nr_of_frames(trace._nr_of_frames),

  _max_frames(trace._max_frames),

  _frames_ownership(true),

  _reached_root(trace._reached_root),

  _lineno(trace._lineno),

  _written(false) {

  copy_frames(&_frames, trace._nr_of_frames, trace._frames);

}

JfrStackTrace::~JfrStackTrace() {

  if (_frames_ownership) {

    FREE_C_HEAP_ARRAY(JfrStackFrame, _frames);

  }

}

template <typename Writer>

static void write_stacktrace(Writer& w, traceid id, bool reached_root, u4 nr_of_frames, const JfrStackFrame* frames) {

  w.write((u8)id);

  w.write((u1)!reached_root);

  w.write(nr_of_frames);

  for (u4 i = 0; i < nr_of_frames; ++i) {

    frames[i].write(w);

  }

}

void JfrStackTrace::write(JfrChunkWriter& sw) const {

  assert(!_written, "invariant");

  write_stacktrace(sw, _id, _reached_root, _nr_of_frames, _frames);

  _written = true;

}

void JfrStackTrace::write(JfrCheckpointWriter& cpw) const {

  write_stacktrace(cpw, _id, _reached_root, _nr_of_frames, _frames);

}

bool JfrStackFrame::equals(const JfrStackFrame& rhs) const {

  return _methodid == rhs._methodid && _bci == rhs._bci && _type == rhs._type;

}

bool JfrStackTrace::equals(const JfrStackTrace& rhs) const {

  if (_reached_root != rhs._reached_root || _nr_of_frames != rhs._nr_of_frames || _hash != rhs._hash) {

    return false;

  }

  for (u4 i = 0; i < _nr_of_frames; ++i) {

    if (!_frames[i].equals(rhs._frames[i])) {

      return false;

    }

  }

  return true;

}

template <typename Writer>

static void write_frame(Writer& w, traceid methodid, int line, int bci, u1 type) {

  w.write((u8)methodid);

  w.write((u4)line);

  w.write((u4)bci);

  w.write((u8)type);

}

void JfrStackFrame::write(JfrChunkWriter& cw) const {

  write_frame(cw, _methodid, _line, _bci, _type);

}

void JfrStackFrame::write(JfrCheckpointWriter& cpw) const {

  write_frame(cpw, _methodid, _line, _bci, _type);

}

class vframeStreamSamples : public vframeStreamCommon {

 public:

  // constructor that starts with sender of frame fr (top_frame)

  vframeStreamSamples(JavaThread *jt, frame fr, bool stop_at_java_call_stub) : vframeStreamCommon(jt) {

    _stop_at_java_call_stub = stop_at_java_call_stub;

    _frame = fr;

    // We must always have a valid frame to start filling

    bool filled_in = fill_from_frame();

    assert(filled_in, "invariant");

  }

  void samples_next();

  void stop() {}

};

// Solaris SPARC Compiler1 needs an additional check on the grandparent

// of the top_frame when the parent of the top_frame is interpreted and

// the grandparent is compiled. However, in this method we do not know

// the relationship of the current _frame relative to the top_frame so

// we implement a more broad sanity check. When the previous callee is

// interpreted and the current sender is compiled, we verify that the

// current sender is also walkable. If it is not walkable, then we mark

// the current vframeStream as at the end.

void vframeStreamSamples::samples_next() {

  // handle frames with inlining

  if (_mode == compiled_mode &&

    vframeStreamCommon::fill_in_compiled_inlined_sender()) {

    return;

  }

  // handle general case

  u4 loop_count = 0;

  u4 loop_max = MAX_STACK_DEPTH * 2;

  do {

    loop_count++;

    // By the time we get here we should never see unsafe but better safe then segv'd

    if (loop_count > loop_max || !_frame.safe_for_sender(_thread)) {

      _mode = at_end_mode;

      return;

    }

    _frame = _frame.sender(&_reg_map);

  } while (!fill_from_frame());

}

bool JfrStackTrace::record_thread(JavaThread& thread, frame& frame) {

  vframeStreamSamples st(&thread, frame, false);

  u4 count = 0;

  _reached_root = true;

  while (!st.at_end()) {

    if (count >= _max_frames) {

      _reached_root = false;

      break;

    }

    const Method* method = st.method();

    if (!Method::is_valid_method(method)) {

      // we throw away everything we've gathered in this sample since

      // none of it is safe

      return false;

    }

    const traceid mid = JfrTraceId::use(method);

    int type = st.is_interpreted_frame() ? JfrStackFrame::FRAME_INTERPRETER : JfrStackFrame::FRAME_JIT;

    int bci = 0;

    if (method->is_native()) {

      type = JfrStackFrame::FRAME_NATIVE;

    } else {

      bci = st.bci();

    }

    const int lineno = method->line_number_from_bci(bci);

    // Can we determine if it's inlined?

    _hash = (_hash << 2) + (unsigned int)(((size_t)mid >> 2) + (bci << 4) + type);

    _frames[count] = JfrStackFrame(mid, bci, type, method);

    st.samples_next();

    count++;

  }

  _lineno = true;

  _nr_of_frames = count;

  return true;

}

void JfrStackFrame::resolve_lineno() const {

  assert(_method, "no method pointer");

  assert(_line == 0, "already have linenumber");

  _line = _method->line_number_from_bci(_bci);

}

void JfrStackTrace::resolve_linenos() const {

  for (unsigned int i = 0; i < _nr_of_frames; i++) {

    _frames[i].resolve_lineno();

  }

  _lineno = true;

}

bool JfrStackTrace::record_safe(JavaThread* thread, int skip) {

  assert(thread == Thread::current(), "Thread stack needs to be walkable");

  vframeStream vfs(thread);

  u4 count = 0;

  _reached_root = true;

  for (int i = 0; i < skip; i++) {

    if (vfs.at_end()) {

      break;

    }

    vfs.next();

  }

  while (!vfs.at_end()) {

    if (count >= _max_frames) {

      _reached_root = false;

      break;

    }

    const Method* method = vfs.method();

    const traceid mid = JfrTraceId::use(method);

    int type = vfs.is_interpreted_frame() ? JfrStackFrame::FRAME_INTERPRETER : JfrStackFrame::FRAME_JIT;

    int bci = 0;

    if (method->is_native()) {

      type = JfrStackFrame::FRAME_NATIVE;

    }

    else {

      bci = vfs.bci();

    }

    // Can we determine if it's inlined?

    _hash = (_hash << 2) + (unsigned int)(((size_t)mid >> 2) + (bci << 4) + type);

    _frames[count] = JfrStackFrame(mid, bci, type, method);

    vfs.next();

    count++;

  }

  _nr_of_frames = count;

  return true;

}