Mercurial > hg > graal-jvmci-8
diff src/share/vm/code/debugInfoRec.cpp @ 0:a61af66fc99e jdk7-b24
Initial load
author | duke |
---|---|
date | Sat, 01 Dec 2007 00:00:00 +0000 |
parents | |
children | 9987d9d5eb0e |
line wrap: on
line diff
--- /dev/null Thu Jan 01 00:00:00 1970 +0000 +++ b/src/share/vm/code/debugInfoRec.cpp Sat Dec 01 00:00:00 2007 +0000 @@ -0,0 +1,411 @@ +/* + * 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 && + 0 == 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