Mercurial > jdk8-mips64-public > hotspot / file revision

 /*

  * Copyright (c) 2003, 2012, 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/systemDictionary.hpp"

 #include "interpreter/interpreter.hpp"

 #include "jvmtifiles/jvmtiEnv.hpp"

 #include "memory/resourceArea.hpp"

 #include "prims/jvmtiEnvThreadState.hpp"

 #include "prims/jvmtiEventController.inline.hpp"

 #include "prims/jvmtiImpl.hpp"

 #include "runtime/handles.hpp"

 #include "runtime/handles.inline.hpp"

 #include "runtime/interfaceSupport.hpp"

 #include "runtime/javaCalls.hpp"

 #include "runtime/signature.hpp"

 #include "runtime/vframe.hpp"

 #include "runtime/vm_operations.hpp"

 ///////////////////////////////////////////////////////////////

 //

 // class JvmtiFramePop

 //

 #ifndef PRODUCT

 void JvmtiFramePop::print() {

   tty->print_cr("_frame_number=%d", _frame_number);

 }

 #endif

 ///////////////////////////////////////////////////////////////

 //

 // class JvmtiFramePops - private methods

 //

 void

 JvmtiFramePops::set(JvmtiFramePop& fp) {

   if (_pops->find(fp.frame_number()) < 0) {

     _pops->append(fp.frame_number());

   }

 }

 void

 JvmtiFramePops::clear(JvmtiFramePop& fp) {

   assert(_pops->length() > 0, "No more frame pops");

   _pops->remove(fp.frame_number());

 }

 int

 JvmtiFramePops::clear_to(JvmtiFramePop& fp) {

   int cleared = 0;

   int index = 0;

   while (index < _pops->length()) {

     JvmtiFramePop pop = JvmtiFramePop(_pops->at(index));

     if (pop.above_on_stack(fp)) {

       _pops->remove_at(index);

       ++cleared;

     } else {

       ++index;

     }

   }

   return cleared;

 }

 ///////////////////////////////////////////////////////////////

 //

 // class JvmtiFramePops - public methods

 //

 JvmtiFramePops::JvmtiFramePops() {

   _pops = new (ResourceObj::C_HEAP, mtInternal) GrowableArray<int> (2, true);

 }

 JvmtiFramePops::~JvmtiFramePops() {

   // return memory to c_heap.

   delete _pops;

 }

 #ifndef PRODUCT

 void JvmtiFramePops::print() {

   ResourceMark rm;

   int n = _pops->length();

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

     JvmtiFramePop fp = JvmtiFramePop(_pops->at(i));

     tty->print("%d: ", i);

     fp.print();

     tty->print_cr("");

   }

 }

 #endif

 ///////////////////////////////////////////////////////////////

 //

 // class JvmtiEnvThreadState

 //

 // Instances of JvmtiEnvThreadState hang off of each JvmtiThreadState,

 // one per JvmtiEnv.

 //

 JvmtiEnvThreadState::JvmtiEnvThreadState(JavaThread *thread, JvmtiEnvBase *env) :

   _event_enable() {

   _thread                 = thread;

   _env                    = (JvmtiEnv*)env;

   _next                   = NULL;

   _frame_pops             = NULL;

   _current_bci            = 0;

   _current_method_id      = NULL;

   _breakpoint_posted      = false;

   _single_stepping_posted = false;

   _agent_thread_local_storage_data = NULL;

 }

 JvmtiEnvThreadState::~JvmtiEnvThreadState()   {

   delete _frame_pops;

   _frame_pops = NULL;

 }

 // Given that a new (potential) event has come in,

 // maintain the current JVMTI location on a per-thread per-env basis

 // and use it to filter out duplicate events:

 // - instruction rewrites

 // - breakpoint followed by single step

 // - single step at a breakpoint

 void JvmtiEnvThreadState::compare_and_set_current_location(Method* new_method,

                                                            address new_location, jvmtiEvent event) {

   int new_bci = new_location - new_method->code_base();

   // The method is identified and stored as a jmethodID which is safe in this

   // case because the class cannot be unloaded while a method is executing.

   jmethodID new_method_id = new_method->jmethod_id();

   // the last breakpoint or single step was at this same location

   if (_current_bci == new_bci && _current_method_id == new_method_id) {

     switch (event) {

     case JVMTI_EVENT_BREAKPOINT:

       // Repeat breakpoint is complicated. If we previously posted a breakpoint

       // event at this location and if we also single stepped at this location

       // then we skip the duplicate breakpoint.

       _breakpoint_posted = _breakpoint_posted && _single_stepping_posted;

       break;

     case JVMTI_EVENT_SINGLE_STEP:

       // Repeat single step is easy: just don't post it again.

       // 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.

       // This has been handled by clearing the location

       _single_stepping_posted = true;

       break;

     default:

       assert(false, "invalid event value passed");

       break;

     }

     return;

   }

   set_current_location(new_method_id, new_bci);

   _breakpoint_posted = false;

   _single_stepping_posted = false;

 }

 JvmtiFramePops* JvmtiEnvThreadState::get_frame_pops() {

 #ifdef ASSERT

   uint32_t debug_bits = 0;

 #endif

   assert(get_thread() == Thread::current() || JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),

          "frame pop data only accessible from same thread or while suspended");

   if (_frame_pops == NULL) {

     _frame_pops = new JvmtiFramePops();

     assert(_frame_pops != NULL, "_frame_pops != NULL");

   }

   return _frame_pops;

 }

 bool JvmtiEnvThreadState::has_frame_pops() {

   return _frame_pops == NULL? false : (_frame_pops->length() > 0);

 }

 void JvmtiEnvThreadState::set_frame_pop(int frame_number) {

 #ifdef ASSERT

   uint32_t debug_bits = 0;

 #endif

   assert(get_thread() == Thread::current() || JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),

          "frame pop data only accessible from same thread or while suspended");

   JvmtiFramePop fpop(frame_number);

   JvmtiEventController::set_frame_pop(this, fpop);

 }

 void JvmtiEnvThreadState::clear_frame_pop(int frame_number) {

 #ifdef ASSERT

   uint32_t debug_bits = 0;

 #endif

   assert(get_thread() == Thread::current() || JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),

          "frame pop data only accessible from same thread or while suspended");

   JvmtiFramePop fpop(frame_number);

   JvmtiEventController::clear_frame_pop(this, fpop);

 }

 void JvmtiEnvThreadState::clear_to_frame_pop(int frame_number)  {

 #ifdef ASSERT

   uint32_t debug_bits = 0;

 #endif

   assert(get_thread() == Thread::current() || JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),

          "frame pop data only accessible from same thread or while suspended");

   JvmtiFramePop fpop(frame_number);

   JvmtiEventController::clear_to_frame_pop(this, fpop);

 }

 bool JvmtiEnvThreadState::is_frame_pop(int cur_frame_number) {

 #ifdef ASSERT

   uint32_t debug_bits = 0;

 #endif

   assert(get_thread() == Thread::current() || JvmtiEnv::is_thread_fully_suspended(get_thread(), false, &debug_bits),

          "frame pop data only accessible from same thread or while suspended");

   if (!get_thread()->is_interp_only_mode() || _frame_pops == NULL) {

     return false;

   }

   JvmtiFramePop fp(cur_frame_number);

   return get_frame_pops()->contains(fp);

 }

 class VM_GetCurrentLocation : public VM_Operation {

  private:

    JavaThread *_thread;

    jmethodID _method_id;

    int _bci;

  public:

   VM_GetCurrentLocation(JavaThread *thread) {

      _thread = thread;

    }

   VMOp_Type type() const { return VMOp_GetCurrentLocation; }

   void doit() {

     ResourceMark rmark; // _thread != Thread::current()

     RegisterMap rm(_thread, false);

     javaVFrame* vf = _thread->last_java_vframe(&rm);

     assert(vf != NULL, "must have last java frame");

     Method* method = vf->method();

     _method_id = method->jmethod_id();

     _bci = vf->bci();

   }

   void get_current_location(jmethodID *method_id, int *bci) {

     *method_id = _method_id;

     *bci = _bci;

   }

 };

 void JvmtiEnvThreadState::reset_current_location(jvmtiEvent event_type, bool enabled) {

   assert(event_type == JVMTI_EVENT_SINGLE_STEP || event_type == JVMTI_EVENT_BREAKPOINT,

          "must be single-step or breakpoint event");

   // Current location is used to detect the following:

   // 1) a breakpoint event followed by single-stepping to the same bci

   // 2) single-step to a bytecode that will be transformed to a fast version

   // We skip to avoid posting the duplicate single-stepping event.

   // If single-stepping is disabled, clear current location so that

   // single-stepping to the same method and bcp at a later time will be

   // detected if single-stepping is enabled at that time (see 4388912).

   // If single-stepping is enabled, set the current location to the

   // current method and bcp. This covers the following type of case,

   // e.g., the debugger stepi command:

   // - bytecode single stepped

   // - SINGLE_STEP event posted and SINGLE_STEP event disabled

   // - SINGLE_STEP event reenabled

   // - bytecode rewritten to fast version

   // If breakpoint event is disabled, clear current location only if

   // single-stepping is not enabled.  Otherwise, keep the thread location

   // to detect any duplicate events.

   if (enabled) {

     // If enabling breakpoint, no need to reset.

     // Can't do anything if empty stack.

     if (event_type == JVMTI_EVENT_SINGLE_STEP && _thread->has_last_Java_frame()) {

       jmethodID method_id;

       int bci;

       // The java thread stack may not be walkable for a running thread

       // so get current location at safepoint.

       VM_GetCurrentLocation op(_thread);

       VMThread::execute(&op);

       op.get_current_location(&method_id, &bci);

       set_current_location(method_id, bci);

     }

   } else if (event_type == JVMTI_EVENT_SINGLE_STEP || !is_enabled(JVMTI_EVENT_SINGLE_STEP)) {

     // If this is to disable breakpoint, also check if single-step is not enabled

     clear_current_location();

   }

 }