--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/share/vm/prims/jvmtiThreadState.cpp	Sat Dec 01 00:00:00 2007 +0000
@@ -0,0 +1,394 @@
+/*
+ * Copyright 2003-2006 Sun Microsystems, Inc.  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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
+ * CA 95054 USA or visit www.sun.com if you need additional information or
+ * have any questions.
+ *
+ */
+
+# include "incls/_precompiled.incl"
+# include "incls/_jvmtiThreadState.cpp.incl"
+
+// marker for when the stack depth has been reset and is now unknown.
+// any negative number would work but small ones might obscure an
+// underrun error.
+static const int UNKNOWN_STACK_DEPTH = -99;
+
+///////////////////////////////////////////////////////////////
+//
+// class JvmtiThreadState
+//
+// Instances of JvmtiThreadState hang off of each thread.
+// Thread local storage for JVMTI.
+//
+
+JvmtiThreadState *JvmtiThreadState::_head = NULL;
+
+JvmtiThreadState::JvmtiThreadState(JavaThread* thread)
+  : _thread_event_enable() {
+  assert(JvmtiThreadState_lock->is_locked(), "sanity check");
+  _thread               = thread;
+  _exception_detected   = false;
+  _exception_caught     = false;
+  _debuggable           = true;
+  _hide_single_stepping = false;
+  _hide_level           = 0;
+  _pending_step_for_popframe = false;
+  _class_being_redefined = NULL;
+  _class_load_kind = jvmti_class_load_kind_load;
+  _head_env_thread_state = NULL;
+  _dynamic_code_event_collector = NULL;
+  _vm_object_alloc_event_collector = NULL;
+  _the_class_for_redefinition_verification = NULL;
+  _scratch_class_for_redefinition_verification = NULL;
+
+  // JVMTI ForceEarlyReturn support
+  _pending_step_for_earlyret = false;
+  _earlyret_state = earlyret_inactive;
+  _earlyret_tos = ilgl;
+  _earlyret_value.j = 0L;
+  _earlyret_oop = NULL;
+
+  // add all the JvmtiEnvThreadState to the new JvmtiThreadState
+  {
+    JvmtiEnvIterator it;
+    for (JvmtiEnvBase* env = it.first(); env != NULL; env = it.next(env)) {
+      if (env->is_valid()) {
+        add_env(env);
+      }
+    }
+  }
+
+  // link us into the list
+  {
+    // The thread state list manipulation code must not have safepoints.
+    // See periodic_clean_up().
+    debug_only(No_Safepoint_Verifier nosafepoint;)
+
+    _prev = NULL;
+    _next = _head;
+    if (_head != NULL) {
+      _head->_prev = this;
+    }
+    _head = this;
+  }
+
+  // set this as the state for the thread
+  thread->set_jvmti_thread_state(this);
+}
+
+
+JvmtiThreadState::~JvmtiThreadState()   {
+  assert(JvmtiThreadState_lock->is_locked(), "sanity check");
+
+  // clear this as the state for the thread
+  get_thread()->set_jvmti_thread_state(NULL);
+
+  // zap our env thread states
+  {
+    JvmtiEnvBase::entering_dying_thread_env_iteration();
+    JvmtiEnvThreadStateIterator it(this);
+    for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ) {
+      JvmtiEnvThreadState* zap = ets;
+      ets = it.next(ets);
+      delete zap;
+    }
+    JvmtiEnvBase::leaving_dying_thread_env_iteration();
+  }
+
+  // remove us from the list
+  {
+    // The thread state list manipulation code must not have safepoints.
+    // See periodic_clean_up().
+    debug_only(No_Safepoint_Verifier nosafepoint;)
+
+    if (_prev == NULL) {
+      assert(_head == this, "sanity check");
+      _head = _next;
+    } else {
+      assert(_head != this, "sanity check");
+      _prev->_next = _next;
+    }
+    if (_next != NULL) {
+      _next->_prev = _prev;
+    }
+    _next = NULL;
+    _prev = NULL;
+  }
+}
+
+
+void
+JvmtiThreadState::periodic_clean_up() {
+  assert(SafepointSynchronize::is_at_safepoint(), "at safepoint");
+
+  // This iteration is initialized with "_head" instead of "JvmtiThreadState::first()"
+  // because the latter requires the JvmtiThreadState_lock.
+  // This iteration is safe at a safepoint as well, see the No_Safepoint_Verifier
+  // asserts at all list manipulation sites.
+  for (JvmtiThreadState *state = _head; state != NULL; state = state->next()) {
+    // For each environment thread state corresponding to an invalid environment
+    // unlink it from the list and deallocate it.
+    JvmtiEnvThreadStateIterator it(state);
+    JvmtiEnvThreadState* previous_ets = NULL;
+    JvmtiEnvThreadState* ets = it.first();
+    while (ets != NULL) {
+      if (ets->get_env()->is_valid()) {
+        previous_ets = ets;
+        ets = it.next(ets);
+      } else {
+        // This one isn't valid, remove it from the list and deallocate it
+        JvmtiEnvThreadState* defunct_ets = ets;
+        ets = ets->next();
+        if (previous_ets == NULL) {
+          assert(state->head_env_thread_state() == defunct_ets, "sanity check");
+          state->set_head_env_thread_state(ets);
+        } else {
+          previous_ets->set_next(ets);
+        }
+        delete defunct_ets;
+      }
+    }
+  }
+}
+
+void JvmtiThreadState::add_env(JvmtiEnvBase *env) {
+  assert(JvmtiThreadState_lock->is_locked(), "sanity check");
+
+  JvmtiEnvThreadState *new_ets = new JvmtiEnvThreadState(_thread, env);
+  // add this environment thread state to the end of the list (order is important)
+  {
+    // list deallocation (which occurs at a safepoint) cannot occur simultaneously
+    debug_only(No_Safepoint_Verifier nosafepoint;)
+
+    JvmtiEnvThreadStateIterator it(this);
+    JvmtiEnvThreadState* previous_ets = NULL;
+    for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ets = it.next(ets)) {
+      previous_ets = ets;
+    }
+    if (previous_ets == NULL) {
+      set_head_env_thread_state(new_ets);
+    } else {
+      previous_ets->set_next(new_ets);
+    }
+  }
+}
+
+
+
+
+void JvmtiThreadState::enter_interp_only_mode() {
+  assert(_thread->get_interp_only_mode() == 0, "entering interp only when mode not zero");
+  _thread->increment_interp_only_mode();
+}
+
+
+void JvmtiThreadState::leave_interp_only_mode() {
+  assert(_thread->get_interp_only_mode() == 1, "leaving interp only when mode not one");
+  _thread->decrement_interp_only_mode();
+}
+
+
+// Helper routine used in several places
+int JvmtiThreadState::count_frames() {
+#ifdef ASSERT
+  uint32_t debug_bits = 0;
+#endif
+  assert(SafepointSynchronize::is_at_safepoint() ||
+         JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),
+         "at safepoint or must be suspended");
+
+  if (!get_thread()->has_last_Java_frame()) return 0;  // no Java frames
+
+  ResourceMark rm;
+  RegisterMap reg_map(get_thread());
+  javaVFrame *jvf = get_thread()->last_java_vframe(&reg_map);
+  int n = 0;
+  // tty->print_cr("CSD: counting frames on %s ...",
+  //               JvmtiTrace::safe_get_thread_name(get_thread()));
+  while (jvf != NULL) {
+    methodOop method = jvf->method();
+    // tty->print_cr("CSD: frame - method %s.%s - loc %d",
+    //               method->klass_name()->as_C_string(),
+    //               method->name()->as_C_string(),
+    //               jvf->bci() );
+    jvf = jvf->java_sender();
+    n++;
+  }
+  // tty->print_cr("CSD: frame count: %d", n);
+  return n;
+}
+
+
+void JvmtiThreadState::invalidate_cur_stack_depth() {
+  Thread *cur = Thread::current();
+  uint32_t debug_bits = 0;
+
+  // The caller can be the VMThread at a safepoint, the current thread
+  // or the target thread must be suspended.
+  guarantee((cur->is_VM_thread() && SafepointSynchronize::is_at_safepoint()) ||
+    (JavaThread *)cur == get_thread() ||
+    JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),
+    "sanity check");
+
+  _cur_stack_depth = UNKNOWN_STACK_DEPTH;
+}
+
+void JvmtiThreadState::incr_cur_stack_depth() {
+  guarantee(JavaThread::current() == get_thread(), "must be current thread");
+
+  if (!is_interp_only_mode()) {
+    _cur_stack_depth = UNKNOWN_STACK_DEPTH;
+  }
+  if (_cur_stack_depth != UNKNOWN_STACK_DEPTH) {
+    ++_cur_stack_depth;
+  }
+}
+
+void JvmtiThreadState::decr_cur_stack_depth() {
+  guarantee(JavaThread::current() == get_thread(), "must be current thread");
+
+  if (!is_interp_only_mode()) {
+    _cur_stack_depth = UNKNOWN_STACK_DEPTH;
+  }
+  if (_cur_stack_depth != UNKNOWN_STACK_DEPTH) {
+    --_cur_stack_depth;
+    assert(_cur_stack_depth >= 0, "incr/decr_cur_stack_depth mismatch");
+  }
+}
+
+int JvmtiThreadState::cur_stack_depth() {
+  uint32_t debug_bits = 0;
+  guarantee(JavaThread::current() == get_thread() ||
+    JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),
+    "must be current thread or suspended");
+
+  if (!is_interp_only_mode() || _cur_stack_depth == UNKNOWN_STACK_DEPTH) {
+    _cur_stack_depth = count_frames();
+  } else {
+    // heavy weight assert
+    assert(_cur_stack_depth == count_frames(),
+           "cur_stack_depth out of sync");
+  }
+  return _cur_stack_depth;
+}
+
+bool JvmtiThreadState::may_be_walked() {
+  return (get_thread()->is_being_ext_suspended() || (JavaThread::current() == get_thread()));
+}
+
+
+void JvmtiThreadState::process_pending_step_for_popframe() {
+  // We are single stepping as the last part of the PopFrame() dance
+  // so we have some house keeping to do.
+
+  JavaThread *thr = get_thread();
+  if (thr->popframe_condition() != JavaThread::popframe_inactive) {
+    // If the popframe_condition field is not popframe_inactive, then
+    // we missed all of the popframe_field cleanup points:
+    //
+    // - unpack_frames() was not called (nothing to deopt)
+    // - remove_activation_preserving_args_entry() was not called
+    //   (did not get suspended in a call_vm() family call and did
+    //   not complete a call_vm() family call on the way here)
+    thr->clear_popframe_condition();
+  }
+
+  // clearing the flag indicates we are done with the PopFrame() dance
+  clr_pending_step_for_popframe();
+
+  // If step is pending for popframe then it may not be
+  // a repeat step. The new_bci and method_id is same as current_bci
+  // and current method_id after pop and step for recursive calls.
+  // Force the step by clearing the last location.
+  JvmtiEnvThreadStateIterator it(this);
+  for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ets = it.next(ets)) {
+    ets->clear_current_location();
+  }
+}
+
+
+// Class:     JvmtiThreadState
+// Function:  update_for_pop_top_frame
+// Description:
+//   This function removes any frame pop notification request for
+//   the top frame and invalidates both the current stack depth and
+//   all cached frameIDs.
+//
+// Called by: PopFrame
+//
+void JvmtiThreadState::update_for_pop_top_frame() {
+  if (is_interp_only_mode()) {
+    // remove any frame pop notification request for the top frame
+    // in any environment
+    int popframe_number = cur_stack_depth();
+    {
+      JvmtiEnvThreadStateIterator it(this);
+      for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ets = it.next(ets)) {
+        if (ets->is_frame_pop(popframe_number)) {
+          ets->clear_frame_pop(popframe_number);
+        }
+      }
+    }
+    // force stack depth to be recalculated
+    invalidate_cur_stack_depth();
+  } else {
+    assert(!is_enabled(JVMTI_EVENT_FRAME_POP), "Must have no framepops set");
+  }
+}
+
+
+void JvmtiThreadState::process_pending_step_for_earlyret() {
+  // We are single stepping as the last part of the ForceEarlyReturn
+  // dance so we have some house keeping to do.
+
+  if (is_earlyret_pending()) {
+    // If the earlyret_state field is not earlyret_inactive, then
+    // we missed all of the earlyret_field cleanup points:
+    //
+    // - remove_activation() was not called
+    //   (did not get suspended in a call_vm() family call and did
+    //   not complete a call_vm() family call on the way here)
+    //
+    // One legitimate way for us to miss all the cleanup points is
+    // if we got here right after handling a compiled return. If that
+    // is the case, then we consider our return from compiled code to
+    // complete the ForceEarlyReturn request and we clear the condition.
+    clr_earlyret_pending();
+    set_earlyret_oop(NULL);
+    clr_earlyret_value();
+  }
+
+  // clearing the flag indicates we are done with
+  // the ForceEarlyReturn() dance
+  clr_pending_step_for_earlyret();
+
+  // If step is pending for earlyret then it may not be a repeat step.
+  // The new_bci and method_id is same as current_bci and current
+  // method_id after earlyret and step for recursive calls.
+  // Force the step by clearing the last location.
+  JvmtiEnvThreadStateIterator it(this);
+  for (JvmtiEnvThreadState* ets = it.first(); ets != NULL; ets = it.next(ets)) {
+    ets->clear_current_location();
+  }
+}
+
+void JvmtiThreadState::oops_do(OopClosure* f) {
+  f->do_oop((oop*) &_earlyret_oop);
+}