| /* |
| * Copyright (c) 1998, 2013, 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 "code/debugInfoRec.hpp" |
| #include "code/scopeDesc.hpp" |
| #include "prims/jvmtiExport.hpp" |
| |
| // 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) |
| #if INCLUDE_JVMCI |
| DebugInformationRecorder* _DIR; |
| #endif |
| |
| void* operator new(size_t ignore, DebugInformationRecorder* dir) throw() { |
| 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; |
| #if INCLUDE_JVMCI |
| _DIR = dir; |
| #endif |
| 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 && |
| 0 == memcmp(buf + this->_offset, buf + that->_offset, length)) { |
| return that; |
| } |
| } |
| return NULL; |
| } |
| |
| #if INCLUDE_JVMCI |
| static int compare(DIR_Chunk* const & a, DIR_Chunk* const & b) { |
| if (b->_hash > a->_hash) { |
| return 1; |
| } |
| if (b->_hash < a->_hash) { |
| return -1; |
| } |
| if (b->_length > a->_length) { |
| return 1; |
| } |
| if (b->_length < a->_length) { |
| return -1; |
| } |
| address buf = a->_DIR->stream()->buffer(); |
| return memcmp(buf + b->_offset, buf + a->_offset, a->_length); |
| } |
| #endif |
| }; |
| |
| 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); |
| #if !INCLUDE_JVMCI |
| _shared_chunks = new GrowableArray<DIR_Chunk*>(30); |
| #endif |
| _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) { |
| #if !INCLUDE_JVMCI |
| // Only pull this trick if non-safepoint recording |
| // is enabled, for now. |
| if (!recording_non_safepoints()) { |
| return serialized_null; |
| } |
| #endif // INCLUDE_JVMCI |
| |
| 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); |
| |
| #if INCLUDE_JVMCI |
| DIR_Chunk* match = _all_chunks->insert_sorted<DIR_Chunk::compare>(ns); |
| if (match != ns) { |
| // Found an existing chunk |
| NOT_PRODUCT(++dir_stats.chunks_shared); |
| assert(ns+1 == _next_chunk, ""); |
| _next_chunk = ns; |
| return match->_offset; |
| } else { |
| // Inserted this chunk, so nothing to do |
| return serialized_null; |
| } |
| #else // INCLUDE_JVMCI |
| // 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; |
| #endif // INCLUDE_JVMCI |
| } |
| |
| |
| // must call add_safepoint before: it sets PcDesc and this routine uses |
| // the last PcDesc set |
| void DebugInformationRecorder::describe_scope(int pc_offset, |
| methodHandle methodH, |
| ciMethod* method, |
| int bci, |
| bool reexecute, |
| bool rethrow_exception, |
| bool is_method_handle_invoke, |
| bool return_oop, |
| 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); |
| |
| // Record flags into pcDesc. |
| last_pd->set_should_reexecute(reexecute); |
| last_pd->set_rethrow_exception(rethrow_exception); |
| last_pd->set_is_method_handle_invoke(is_method_handle_invoke); |
| last_pd->set_return_oop(return_oop); |
| |
| // serialize sender stream offest |
| stream()->write_int(sender_stream_offset); |
| |
| // serialize scope |
| Metadata* method_enc; |
| if (method != NULL) { |
| method_enc = method->constant_encoding(); |
| } else if (methodH.not_null()) { |
| method_enc = methodH(); |
| } else { |
| method_enc = NULL; |
| } |
| int method_enc_index = oop_recorder()->find_index(method_enc); |
| stream()->write_int(method_enc_index); |
| stream()->write_bci(bci); |
| assert(method == NULL || |
| (method->is_native() && bci == 0) || |
| (!method->is_native() && 0 <= bci && bci < method->code_size()) || |
| (method->is_compiled_lambda_form() && bci == -99) || // this might happen in C1 |
| 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--) { |
| objects->at(i)->as_ObjectValue()->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->is_same_info(last)) { |
| 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; |
| } |
| } |
| |
| #ifdef ASSERT |
| bool DebugInformationRecorder::recorders_frozen() { |
| return _oop_recorder->is_complete() || _oop_recorder->is_complete(); |
| } |
| |
| void DebugInformationRecorder::mark_recorders_frozen() { |
| _oop_recorder->freeze(); |
| } |
| #endif // PRODUCT |
| |
| DebugToken* DebugInformationRecorder::create_scope_values(GrowableArray<ScopeValue*>* values) { |
| assert(!recorders_frozen(), "not frozen yet"); |
| return (DebugToken*) (intptr_t) serialize_scope_values(values); |
| } |
| |
| |
| DebugToken* DebugInformationRecorder::create_monitor_values(GrowableArray<MonitorValue*>* monitors) { |
| assert(!recorders_frozen(), "not frozen yet"); |
| return (DebugToken*) (intptr_t) serialize_monitor_values(monitors); |
| } |
| |
| |
| int DebugInformationRecorder::data_size() { |
| debug_only(mark_recorders_frozen()); // mark it "frozen" for asserts |
| return _stream->position(); |
| } |
| |
| |
| int DebugInformationRecorder::pcs_size() { |
| debug_only(mark_recorders_frozen()); // 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 |