jdk8-mips64-public/hotspot: src/share/vm/code/debugInfoRec.cpp@1d037ecd7960 (annotated)

src/share/vm/code/debugInfoRec.cpp@1d037ecd7960 (annotated)

src/share/vm/code/debugInfoRec.cpp

Wed, 08 Apr 2009 00:12:59 -0700

author: jrose
date: Wed, 08 Apr 2009 00:12:59 -0700
changeset 1144: 1d037ecd7960
parent 435: a61af66fc99e
child 1335: 9987d9d5eb0e
permissions: -rw-r--r--

6827505: sizing logic for vtable and itable stubs needs self-check
Summary: Asserts and comments to help maintain the correct sizing of certain stubs
Reviewed-by: kvn

 /*
  * Copyright 1998-2006 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/_debugInfoRec.cpp.incl"
 // Private definition.
 // There is one DIR_Chunk for each scope and values array.
 // A chunk can potentially be used more than once.
 // We keep track of these chunks in order to detect
 // repetition and enable sharing.
 class DIR_Chunk {
   friend class DebugInformationRecorder;
   int  _offset; // location in the stream of this scope
   int  _length; // number of bytes in the stream
   int  _hash;   // hash of stream bytes (for quicker reuse)
   void* operator new(size_t ignore, DebugInformationRecorder* dir) {
     assert(ignore == sizeof(DIR_Chunk), "");
     if (dir->_next_chunk >= dir->_next_chunk_limit) {
       const int CHUNK = 100;
       dir->_next_chunk = NEW_RESOURCE_ARRAY(DIR_Chunk, CHUNK);
       dir->_next_chunk_limit = dir->_next_chunk + CHUNK;
     }
     return dir->_next_chunk++;
   }
   DIR_Chunk(int offset, int length, DebugInformationRecorder* dir) {
     _offset = offset;
     _length = length;
     unsigned int hash = 0;
     address p = dir->stream()->buffer() + _offset;
     for (int i = 0; i < length; i++) {
       if (i == 6)  break;
       hash *= 127;
       hash += p[i];
     }
     _hash = hash;
   }
   DIR_Chunk* find_match(GrowableArray<DIR_Chunk*>* arr,
                         int start_index,
                         DebugInformationRecorder* dir) {
     int end_index = arr->length();
     int hash = this->_hash, length = this->_length;
     address buf = dir->stream()->buffer();
     for (int i = end_index; --i >= start_index; ) {
       DIR_Chunk* that = arr->at(i);
       if (hash   == that->_hash &&
           length == that->_length &&
 == memcmp(buf + this->_offset, buf + that->_offset, length)) {
         return that;
       }
     }
     return NULL;
   }
 };
 static inline bool compute_recording_non_safepoints() {
   if (JvmtiExport::should_post_compiled_method_load()
       && FLAG_IS_DEFAULT(DebugNonSafepoints)) {
     // The default value of this flag is taken to be true,
     // if JVMTI is looking at nmethod codes.
     // We anticipate that JVMTI may wish to participate in profiling.
     return true;
   }
   // If the flag is set manually, use it, whether true or false.
   // Otherwise, if JVMTI is not in the picture, use the default setting.
   // (This is true in debug, just for the exercise, false in product mode.)
   return DebugNonSafepoints;
 }
 DebugInformationRecorder::DebugInformationRecorder(OopRecorder* oop_recorder)
   : _recording_non_safepoints(compute_recording_non_safepoints())
 {
   _pcs_size   = 100;
   _pcs        = NEW_RESOURCE_ARRAY(PcDesc, _pcs_size);
   _pcs_length = 0;
   _prev_safepoint_pc = PcDesc::lower_offset_limit;
   _stream = new DebugInfoWriteStream(this, 10 * K);
   // make sure that there is no stream_decode_offset that is zero
   _stream->write_byte((jbyte)0xFF);
   // make sure that we can distinguish the value "serialized_null" from offsets
   assert(_stream->position() > serialized_null, "sanity");
   _oop_recorder = oop_recorder;
   _all_chunks    = new GrowableArray<DIR_Chunk*>(300);
   _shared_chunks = new GrowableArray<DIR_Chunk*>(30);
   _next_chunk = _next_chunk_limit = NULL;
   add_new_pc_offset(PcDesc::lower_offset_limit);  // sentinel record
   debug_only(_recording_state = rs_null);
 }
 void DebugInformationRecorder::add_oopmap(int pc_offset, OopMap* map) {
   // !!!!! Preserve old style handling of oopmaps for now
   _oopmaps->add_gc_map(pc_offset, map);
 }
 void DebugInformationRecorder::add_safepoint(int pc_offset, OopMap* map) {
   assert(!_oop_recorder->is_complete(), "not frozen yet");
   // Store the new safepoint
   // Add the oop map
   add_oopmap(pc_offset, map);
   add_new_pc_offset(pc_offset);
   assert(_recording_state == rs_null, "nesting of recording calls");
   debug_only(_recording_state = rs_safepoint);
 }
 void DebugInformationRecorder::add_non_safepoint(int pc_offset) {
   assert(!_oop_recorder->is_complete(), "not frozen yet");
   assert(_recording_non_safepoints, "must be recording non-safepoints");
   add_new_pc_offset(pc_offset);
   assert(_recording_state == rs_null, "nesting of recording calls");
   debug_only(_recording_state = rs_non_safepoint);
 }
 void DebugInformationRecorder::add_new_pc_offset(int pc_offset) {
   assert(_pcs_length == 0 || last_pc()->pc_offset() < pc_offset,
          "must specify a new, larger pc offset");
   // add the pcdesc
   if (_pcs_length == _pcs_size) {
     // Expand
     int     new_pcs_size = _pcs_size * 2;
     PcDesc* new_pcs      = NEW_RESOURCE_ARRAY(PcDesc, new_pcs_size);
     for (int index = 0; index < _pcs_length; index++) {
       new_pcs[index] = _pcs[index];
     }
     _pcs_size = new_pcs_size;
     _pcs      = new_pcs;
   }
   assert(_pcs_size > _pcs_length, "There must be room for after expanding");
   _pcs[_pcs_length++] = PcDesc(pc_offset, DebugInformationRecorder::serialized_null,
                                DebugInformationRecorder::serialized_null);
 }
 int DebugInformationRecorder::serialize_monitor_values(GrowableArray<MonitorValue*>* monitors) {
   if (monitors == NULL || monitors->is_empty()) return DebugInformationRecorder::serialized_null;
   assert(_recording_state == rs_safepoint, "must be recording a safepoint");
   int result = stream()->position();
   stream()->write_int(monitors->length());
   for (int index = 0; index < monitors->length(); index++) {
     monitors->at(index)->write_on(stream());
   }
   assert(result != serialized_null, "sanity");
   // (See comment below on DebugInformationRecorder::describe_scope.)
   int shared_result = find_sharable_decode_offset(result);
   if (shared_result != serialized_null) {
     stream()->set_position(result);
     result = shared_result;
   }
   return result;
 }
 int DebugInformationRecorder::serialize_scope_values(GrowableArray<ScopeValue*>* values) {
   if (values == NULL || values->is_empty()) return DebugInformationRecorder::serialized_null;
   assert(_recording_state == rs_safepoint, "must be recording a safepoint");
   int result = stream()->position();
   assert(result != serialized_null, "sanity");
   stream()->write_int(values->length());
   for (int index = 0; index < values->length(); index++) {
     values->at(index)->write_on(stream());
   }
   // (See comment below on DebugInformationRecorder::describe_scope.)
   int shared_result = find_sharable_decode_offset(result);
   if (shared_result != serialized_null) {
     stream()->set_position(result);
     result = shared_result;
   }
   return result;
 }
 #ifndef PRODUCT
 // These variables are put into one block to reduce relocations
 // and make it simpler to print from the debugger.
 static
 struct dir_stats_struct {
   int chunks_queried;
   int chunks_shared;
   int chunks_reshared;
   int chunks_elided;
   void print() {
     tty->print_cr("Debug Data Chunks: %d, shared %d+%d, non-SP's elided %d",
                   chunks_queried,
                   chunks_shared, chunks_reshared,
                   chunks_elided);
   }
 } dir_stats;
 #endif //PRODUCT
 int DebugInformationRecorder::find_sharable_decode_offset(int stream_offset) {
   // Only pull this trick if non-safepoint recording
   // is enabled, for now.
   if (!recording_non_safepoints())
     return serialized_null;
   NOT_PRODUCT(++dir_stats.chunks_queried);
   int stream_length = stream()->position() - stream_offset;
   assert(stream_offset != serialized_null, "should not be null");
   assert(stream_length != 0, "should not be empty");
   DIR_Chunk* ns = new(this) DIR_Chunk(stream_offset, stream_length, this);
   // Look in previously shared scopes first:
   DIR_Chunk* ms = ns->find_match(_shared_chunks, 0, this);
   if (ms != NULL) {
     NOT_PRODUCT(++dir_stats.chunks_reshared);
     assert(ns+1 == _next_chunk, "");
     _next_chunk = ns;
     return ms->_offset;
   }
   // Look in recently encountered scopes next:
   const int MAX_RECENT = 50;
   int start_index = _all_chunks->length() - MAX_RECENT;
   if (start_index < 0)  start_index = 0;
   ms = ns->find_match(_all_chunks, start_index, this);
   if (ms != NULL) {
     NOT_PRODUCT(++dir_stats.chunks_shared);
     // Searching in _all_chunks is limited to a window,
     // but searching in _shared_chunks is unlimited.
     _shared_chunks->append(ms);
     assert(ns+1 == _next_chunk, "");
     _next_chunk = ns;
     return ms->_offset;
   }
   // No match.  Add this guy to the list, in hopes of future shares.
   _all_chunks->append(ns);
   return serialized_null;
 }
 // must call add_safepoint before: it sets PcDesc and this routine uses
 // the last PcDesc set
 void DebugInformationRecorder::describe_scope(int         pc_offset,
                                               ciMethod*   method,
                                               int         bci,
                                               DebugToken* locals,
                                               DebugToken* expressions,
                                               DebugToken* monitors) {
   assert(_recording_state != rs_null, "nesting of recording calls");
   PcDesc* last_pd = last_pc();
   assert(last_pd->pc_offset() == pc_offset, "must be last pc");
   int sender_stream_offset = last_pd->scope_decode_offset();
   // update the stream offset of current pc desc
   int stream_offset = stream()->position();
   last_pd->set_scope_decode_offset(stream_offset);
   // serialize sender stream offest
   stream()->write_int(sender_stream_offset);
   // serialize scope
   jobject method_enc = (method == NULL)? NULL: method->encoding();
   stream()->write_int(oop_recorder()->find_index(method_enc));
   stream()->write_bci(bci);
   assert(method == NULL ||
          (method->is_native() && bci == 0) ||
          (!method->is_native() && 0 <= bci && bci < method->code_size()) ||
          bci == -1, "illegal bci");
   // serialize the locals/expressions/monitors
   stream()->write_int((intptr_t) locals);
   stream()->write_int((intptr_t) expressions);
   stream()->write_int((intptr_t) monitors);
   // Here's a tricky bit.  We just wrote some bytes.
   // Wouldn't it be nice to find that we had already
   // written those same bytes somewhere else?
   // If we get lucky this way, reset the stream
   // and reuse the old bytes.  By the way, this
   // trick not only shares parent scopes, but also
   // compresses equivalent non-safepoint PcDescs.
   int shared_stream_offset = find_sharable_decode_offset(stream_offset);
   if (shared_stream_offset != serialized_null) {
     stream()->set_position(stream_offset);
     last_pd->set_scope_decode_offset(shared_stream_offset);
   }
 }
 void DebugInformationRecorder::dump_object_pool(GrowableArray<ScopeValue*>* objects) {
   guarantee( _pcs_length > 0, "safepoint must exist before describing scopes");
   PcDesc* last_pd = &_pcs[_pcs_length-1];
   if (objects != NULL) {
     for (int i = objects->length() - 1; i >= 0; i--) {
       ((ObjectValue*) objects->at(i))->set_visited(false);
     }
   }
   int offset = serialize_scope_values(objects);
   last_pd->set_obj_decode_offset(offset);
 }
 void DebugInformationRecorder::end_scopes(int pc_offset, bool is_safepoint) {
   assert(_recording_state == (is_safepoint? rs_safepoint: rs_non_safepoint),
          "nesting of recording calls");
   debug_only(_recording_state = rs_null);
   // Try to compress away an equivalent non-safepoint predecessor.
   // (This only works because we have previously recognized redundant
   // scope trees and made them use a common scope_decode_offset.)
   if (_pcs_length >= 2 && recording_non_safepoints()) {
     PcDesc* last = last_pc();
     PcDesc* prev = prev_pc();
     // If prev is (a) not a safepoint and (b) has the same
     // stream pointer, then it can be coalesced into the last.
     // This is valid because non-safepoints are only sought
     // with pc_desc_near, which (when it misses prev) will
     // search forward until it finds last.
     // In addition, it does not matter if the last PcDesc
     // is for a safepoint or not.
     if (_prev_safepoint_pc < prev->pc_offset() &&
         prev->scope_decode_offset() == last->scope_decode_offset()) {
       assert(prev == last-1, "sane");
       prev->set_pc_offset(pc_offset);
       _pcs_length -= 1;
       NOT_PRODUCT(++dir_stats.chunks_elided);
     }
   }
   // We have just recorded this safepoint.
   // Remember it in case the previous paragraph needs to know.
   if (is_safepoint) {
     _prev_safepoint_pc = pc_offset;
   }
 }
 DebugToken* DebugInformationRecorder::create_scope_values(GrowableArray<ScopeValue*>* values) {
   assert(!_oop_recorder->is_complete(), "not frozen yet");
   return (DebugToken*) (intptr_t) serialize_scope_values(values);
 }
 DebugToken* DebugInformationRecorder::create_monitor_values(GrowableArray<MonitorValue*>* monitors) {
   assert(!_oop_recorder->is_complete(), "not frozen yet");
   return (DebugToken*) (intptr_t) serialize_monitor_values(monitors);
 }
 int DebugInformationRecorder::data_size() {
   debug_only(_oop_recorder->oop_size());  // mark it "frozen" for asserts
   return _stream->position();
 }
 int DebugInformationRecorder::pcs_size() {
   debug_only(_oop_recorder->oop_size());  // mark it "frozen" for asserts
   if (last_pc()->pc_offset() != PcDesc::upper_offset_limit)
     add_new_pc_offset(PcDesc::upper_offset_limit);
   return _pcs_length * sizeof(PcDesc);
 }
 void DebugInformationRecorder::copy_to(nmethod* nm) {
   nm->copy_scopes_data(stream()->buffer(), stream()->position());
   nm->copy_scopes_pcs(_pcs, _pcs_length);
 }
 void DebugInformationRecorder::verify(const nmethod* code) {
   Unimplemented();
 }
 #ifndef PRODUCT
 void DebugInformationRecorder::print_statistics() {
   dir_stats.print();
 }
 #endif //PRODUCT

Mercurial > jdk8-mips64-public > hotspot / annotate

src/share/vm/code/debugInfoRec.cpp@1d037ecd7960 (annotated)

src/share/vm/code/debugInfoRec.cpp