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Java example source code file (c1_GraphBuilder.cpp)
The c1_GraphBuilder.cpp Java example source code/* * Copyright (c) 1999, 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 "c1/c1_CFGPrinter.hpp" #include "c1/c1_Canonicalizer.hpp" #include "c1/c1_Compilation.hpp" #include "c1/c1_GraphBuilder.hpp" #include "c1/c1_InstructionPrinter.hpp" #include "ci/ciCallSite.hpp" #include "ci/ciField.hpp" #include "ci/ciKlass.hpp" #include "ci/ciMemberName.hpp" #include "compiler/compileBroker.hpp" #include "interpreter/bytecode.hpp" #include "runtime/sharedRuntime.hpp" #include "runtime/compilationPolicy.hpp" #include "utilities/bitMap.inline.hpp" class BlockListBuilder VALUE_OBJ_CLASS_SPEC { private: Compilation* _compilation; IRScope* _scope; BlockList _blocks; // internal list of all blocks BlockList* _bci2block; // mapping from bci to blocks for GraphBuilder // fields used by mark_loops BitMap _active; // for iteration of control flow graph BitMap _visited; // for iteration of control flow graph intArray _loop_map; // caches the information if a block is contained in a loop int _next_loop_index; // next free loop number int _next_block_number; // for reverse postorder numbering of blocks // accessors Compilation* compilation() const { return _compilation; } IRScope* scope() const { return _scope; } ciMethod* method() const { return scope()->method(); } XHandlers* xhandlers() const { return scope()->xhandlers(); } // unified bailout support void bailout(const char* msg) const { compilation()->bailout(msg); } bool bailed_out() const { return compilation()->bailed_out(); } // helper functions BlockBegin* make_block_at(int bci, BlockBegin* predecessor); void handle_exceptions(BlockBegin* current, int cur_bci); void handle_jsr(BlockBegin* current, int sr_bci, int next_bci); void store_one(BlockBegin* current, int local); void store_two(BlockBegin* current, int local); void set_entries(int osr_bci); void set_leaders(); void make_loop_header(BlockBegin* block); void mark_loops(); int mark_loops(BlockBegin* b, bool in_subroutine); // debugging #ifndef PRODUCT void print(); #endif public: // creation BlockListBuilder(Compilation* compilation, IRScope* scope, int osr_bci); // accessors for GraphBuilder BlockList* bci2block() const { return _bci2block; } }; // Implementation of BlockListBuilder BlockListBuilder::BlockListBuilder(Compilation* compilation, IRScope* scope, int osr_bci) : _compilation(compilation) , _scope(scope) , _blocks(16) , _bci2block(new BlockList(scope->method()->code_size(), NULL)) , _next_block_number(0) , _active() // size not known yet , _visited() // size not known yet , _next_loop_index(0) , _loop_map() // size not known yet { set_entries(osr_bci); set_leaders(); CHECK_BAILOUT(); mark_loops(); NOT_PRODUCT(if (PrintInitialBlockList) print()); #ifndef PRODUCT if (PrintCFGToFile) { stringStream title; title.print("BlockListBuilder "); scope->method()->print_name(&title); CFGPrinter::print_cfg(_bci2block, title.as_string(), false, false); } #endif } void BlockListBuilder::set_entries(int osr_bci) { // generate start blocks BlockBegin* std_entry = make_block_at(0, NULL); if (scope()->caller() == NULL) { std_entry->set(BlockBegin::std_entry_flag); } if (osr_bci != -1) { BlockBegin* osr_entry = make_block_at(osr_bci, NULL); osr_entry->set(BlockBegin::osr_entry_flag); } // generate exception entry blocks XHandlers* list = xhandlers(); const int n = list->length(); for (int i = 0; i < n; i++) { XHandler* h = list->handler_at(i); BlockBegin* entry = make_block_at(h->handler_bci(), NULL); entry->set(BlockBegin::exception_entry_flag); h->set_entry_block(entry); } } BlockBegin* BlockListBuilder::make_block_at(int cur_bci, BlockBegin* predecessor) { assert(method()->bci_block_start().at(cur_bci), "wrong block starts of MethodLivenessAnalyzer"); BlockBegin* block = _bci2block->at(cur_bci); if (block == NULL) { block = new BlockBegin(cur_bci); block->init_stores_to_locals(method()->max_locals()); _bci2block->at_put(cur_bci, block); _blocks.append(block); assert(predecessor == NULL || predecessor->bci() < cur_bci, "targets for backward branches must already exist"); } if (predecessor != NULL) { if (block->is_set(BlockBegin::exception_entry_flag)) { BAILOUT_("Exception handler can be reached by both normal and exceptional control flow", block); } predecessor->add_successor(block); block->increment_total_preds(); } return block; } inline void BlockListBuilder::store_one(BlockBegin* current, int local) { current->stores_to_locals().set_bit(local); } inline void BlockListBuilder::store_two(BlockBegin* current, int local) { store_one(current, local); store_one(current, local + 1); } void BlockListBuilder::handle_exceptions(BlockBegin* current, int cur_bci) { // Draws edges from a block to its exception handlers XHandlers* list = xhandlers(); const int n = list->length(); for (int i = 0; i < n; i++) { XHandler* h = list->handler_at(i); if (h->covers(cur_bci)) { BlockBegin* entry = h->entry_block(); assert(entry != NULL && entry == _bci2block->at(h->handler_bci()), "entry must be set"); assert(entry->is_set(BlockBegin::exception_entry_flag), "flag must be set"); // add each exception handler only once if (!current->is_successor(entry)) { current->add_successor(entry); entry->increment_total_preds(); } // stop when reaching catchall if (h->catch_type() == 0) break; } } } void BlockListBuilder::handle_jsr(BlockBegin* current, int sr_bci, int next_bci) { // start a new block after jsr-bytecode and link this block into cfg make_block_at(next_bci, current); // start a new block at the subroutine entry at mark it with special flag BlockBegin* sr_block = make_block_at(sr_bci, current); if (!sr_block->is_set(BlockBegin::subroutine_entry_flag)) { sr_block->set(BlockBegin::subroutine_entry_flag); } } void BlockListBuilder::set_leaders() { bool has_xhandlers = xhandlers()->has_handlers(); BlockBegin* current = NULL; // The information which bci starts a new block simplifies the analysis // Without it, backward branches could jump to a bci where no block was created // during bytecode iteration. This would require the creation of a new block at the // branch target and a modification of the successor lists. BitMap bci_block_start = method()->bci_block_start(); ciBytecodeStream s(method()); while (s.next() != ciBytecodeStream::EOBC()) { int cur_bci = s.cur_bci(); if (bci_block_start.at(cur_bci)) { current = make_block_at(cur_bci, current); } assert(current != NULL, "must have current block"); if (has_xhandlers && GraphBuilder::can_trap(method(), s.cur_bc())) { handle_exceptions(current, cur_bci); } switch (s.cur_bc()) { // track stores to local variables for selective creation of phi functions case Bytecodes::_iinc: store_one(current, s.get_index()); break; case Bytecodes::_istore: store_one(current, s.get_index()); break; case Bytecodes::_lstore: store_two(current, s.get_index()); break; case Bytecodes::_fstore: store_one(current, s.get_index()); break; case Bytecodes::_dstore: store_two(current, s.get_index()); break; case Bytecodes::_astore: store_one(current, s.get_index()); break; case Bytecodes::_istore_0: store_one(current, 0); break; case Bytecodes::_istore_1: store_one(current, 1); break; case Bytecodes::_istore_2: store_one(current, 2); break; case Bytecodes::_istore_3: store_one(current, 3); break; case Bytecodes::_lstore_0: store_two(current, 0); break; case Bytecodes::_lstore_1: store_two(current, 1); break; case Bytecodes::_lstore_2: store_two(current, 2); break; case Bytecodes::_lstore_3: store_two(current, 3); break; case Bytecodes::_fstore_0: store_one(current, 0); break; case Bytecodes::_fstore_1: store_one(current, 1); break; case Bytecodes::_fstore_2: store_one(current, 2); break; case Bytecodes::_fstore_3: store_one(current, 3); break; case Bytecodes::_dstore_0: store_two(current, 0); break; case Bytecodes::_dstore_1: store_two(current, 1); break; case Bytecodes::_dstore_2: store_two(current, 2); break; case Bytecodes::_dstore_3: store_two(current, 3); break; case Bytecodes::_astore_0: store_one(current, 0); break; case Bytecodes::_astore_1: store_one(current, 1); break; case Bytecodes::_astore_2: store_one(current, 2); break; case Bytecodes::_astore_3: store_one(current, 3); break; // track bytecodes that affect the control flow case Bytecodes::_athrow: // fall through case Bytecodes::_ret: // fall through case Bytecodes::_ireturn: // fall through case Bytecodes::_lreturn: // fall through case Bytecodes::_freturn: // fall through case Bytecodes::_dreturn: // fall through case Bytecodes::_areturn: // fall through case Bytecodes::_return: current = NULL; break; case Bytecodes::_ifeq: // fall through case Bytecodes::_ifne: // fall through case Bytecodes::_iflt: // fall through case Bytecodes::_ifge: // fall through case Bytecodes::_ifgt: // fall through case Bytecodes::_ifle: // fall through case Bytecodes::_if_icmpeq: // fall through case Bytecodes::_if_icmpne: // fall through case Bytecodes::_if_icmplt: // fall through case Bytecodes::_if_icmpge: // fall through case Bytecodes::_if_icmpgt: // fall through case Bytecodes::_if_icmple: // fall through case Bytecodes::_if_acmpeq: // fall through case Bytecodes::_if_acmpne: // fall through case Bytecodes::_ifnull: // fall through case Bytecodes::_ifnonnull: make_block_at(s.next_bci(), current); make_block_at(s.get_dest(), current); current = NULL; break; case Bytecodes::_goto: make_block_at(s.get_dest(), current); current = NULL; break; case Bytecodes::_goto_w: make_block_at(s.get_far_dest(), current); current = NULL; break; case Bytecodes::_jsr: handle_jsr(current, s.get_dest(), s.next_bci()); current = NULL; break; case Bytecodes::_jsr_w: handle_jsr(current, s.get_far_dest(), s.next_bci()); current = NULL; break; case Bytecodes::_tableswitch: { // set block for each case Bytecode_tableswitch sw(&s); int l = sw.length(); for (int i = 0; i < l; i++) { make_block_at(cur_bci + sw.dest_offset_at(i), current); } make_block_at(cur_bci + sw.default_offset(), current); current = NULL; break; } case Bytecodes::_lookupswitch: { // set block for each case Bytecode_lookupswitch sw(&s); int l = sw.number_of_pairs(); for (int i = 0; i < l; i++) { make_block_at(cur_bci + sw.pair_at(i).offset(), current); } make_block_at(cur_bci + sw.default_offset(), current); current = NULL; break; } } } } void BlockListBuilder::mark_loops() { ResourceMark rm; _active = BitMap(BlockBegin::number_of_blocks()); _active.clear(); _visited = BitMap(BlockBegin::number_of_blocks()); _visited.clear(); _loop_map = intArray(BlockBegin::number_of_blocks(), 0); _next_loop_index = 0; _next_block_number = _blocks.length(); // recursively iterate the control flow graph mark_loops(_bci2block->at(0), false); assert(_next_block_number >= 0, "invalid block numbers"); } void BlockListBuilder::make_loop_header(BlockBegin* block) { if (block->is_set(BlockBegin::exception_entry_flag)) { // exception edges may look like loops but don't mark them as such // since it screws up block ordering. return; } if (!block->is_set(BlockBegin::parser_loop_header_flag)) { block->set(BlockBegin::parser_loop_header_flag); assert(_loop_map.at(block->block_id()) == 0, "must not be set yet"); assert(0 <= _next_loop_index && _next_loop_index < BitsPerInt, "_next_loop_index is used as a bit-index in integer"); _loop_map.at_put(block->block_id(), 1 << _next_loop_index); if (_next_loop_index < 31) _next_loop_index++; } else { // block already marked as loop header assert(is_power_of_2((unsigned int)_loop_map.at(block->block_id())), "exactly one bit must be set"); } } int BlockListBuilder::mark_loops(BlockBegin* block, bool in_subroutine) { int block_id = block->block_id(); if (_visited.at(block_id)) { if (_active.at(block_id)) { // reached block via backward branch make_loop_header(block); } // return cached loop information for this block return _loop_map.at(block_id); } if (block->is_set(BlockBegin::subroutine_entry_flag)) { in_subroutine = true; } // set active and visited bits before successors are processed _visited.set_bit(block_id); _active.set_bit(block_id); intptr_t loop_state = 0; for (int i = block->number_of_sux() - 1; i >= 0; i--) { // recursively process all successors loop_state |= mark_loops(block->sux_at(i), in_subroutine); } // clear active-bit after all successors are processed _active.clear_bit(block_id); // reverse-post-order numbering of all blocks block->set_depth_first_number(_next_block_number); _next_block_number--; if (loop_state != 0 || in_subroutine ) { // block is contained at least in one loop, so phi functions are necessary // phi functions are also necessary for all locals stored in a subroutine scope()->requires_phi_function().set_union(block->stores_to_locals()); } if (block->is_set(BlockBegin::parser_loop_header_flag)) { int header_loop_state = _loop_map.at(block_id); assert(is_power_of_2((unsigned)header_loop_state), "exactly one bit must be set"); // If the highest bit is set (i.e. when integer value is negative), the method // has 32 or more loops. This bit is never cleared because it is used for multiple loops if (header_loop_state >= 0) { clear_bits(loop_state, header_loop_state); } } // cache and return loop information for this block _loop_map.at_put(block_id, loop_state); return loop_state; } #ifndef PRODUCT int compare_depth_first(BlockBegin** a, BlockBegin** b) { return (*a)->depth_first_number() - (*b)->depth_first_number(); } void BlockListBuilder::print() { tty->print("----- initial block list of BlockListBuilder for method "); method()->print_short_name(); tty->cr(); // better readability if blocks are sorted in processing order _blocks.sort(compare_depth_first); for (int i = 0; i < _blocks.length(); i++) { BlockBegin* cur = _blocks.at(i); tty->print("%4d: B%-4d bci: %-4d preds: %-4d ", cur->depth_first_number(), cur->block_id(), cur->bci(), cur->total_preds()); tty->print(cur->is_set(BlockBegin::std_entry_flag) ? " std" : " "); tty->print(cur->is_set(BlockBegin::osr_entry_flag) ? " osr" : " "); tty->print(cur->is_set(BlockBegin::exception_entry_flag) ? " ex" : " "); tty->print(cur->is_set(BlockBegin::subroutine_entry_flag) ? " sr" : " "); tty->print(cur->is_set(BlockBegin::parser_loop_header_flag) ? " lh" : " "); if (cur->number_of_sux() > 0) { tty->print(" sux: "); for (int j = 0; j < cur->number_of_sux(); j++) { BlockBegin* sux = cur->sux_at(j); tty->print("B%d ", sux->block_id()); } } tty->cr(); } } #endif // A simple growable array of Values indexed by ciFields class FieldBuffer: public CompilationResourceObj { private: GrowableArray<Value> _values; public: FieldBuffer() {} void kill() { _values.trunc_to(0); } Value at(ciField* field) { assert(field->holder()->is_loaded(), "must be a loaded field"); int offset = field->offset(); if (offset < _values.length()) { return _values.at(offset); } else { return NULL; } } void at_put(ciField* field, Value value) { assert(field->holder()->is_loaded(), "must be a loaded field"); int offset = field->offset(); _values.at_put_grow(offset, value, NULL); } }; // MemoryBuffer is fairly simple model of the current state of memory. // It partitions memory into several pieces. The first piece is // generic memory where little is known about the owner of the memory. // This is conceptually represented by the tuple <O, F, V> which says // that the field F of object O has value V. This is flattened so // that F is represented by the offset of the field and the parallel // arrays _objects and _values are used for O and V. Loads of O.F can // simply use V. Newly allocated objects are kept in a separate list // along with a parallel array for each object which represents the // current value of its fields. Stores of the default value to fields // which have never been stored to before are eliminated since they // are redundant. Once newly allocated objects are stored into // another object or they are passed out of the current compile they // are treated like generic memory. class MemoryBuffer: public CompilationResourceObj { private: FieldBuffer _values; GrowableArray<Value> _objects; GrowableArray<Value> _newobjects; GrowableArray<FieldBuffer*> _fields; public: MemoryBuffer() {} StoreField* store(StoreField* st) { if (!EliminateFieldAccess) { return st; } Value object = st->obj(); Value value = st->value(); ciField* field = st->field(); if (field->holder()->is_loaded()) { int offset = field->offset(); int index = _newobjects.find(object); if (index != -1) { // newly allocated object with no other stores performed on this field FieldBuffer* buf = _fields.at(index); if (buf->at(field) == NULL && is_default_value(value)) { #ifndef PRODUCT if (PrintIRDuringConstruction && Verbose) { tty->print_cr("Eliminated store for object %d:", index); st->print_line(); } #endif return NULL; } else { buf->at_put(field, value); } } else { _objects.at_put_grow(offset, object, NULL); _values.at_put(field, value); } store_value(value); } else { // if we held onto field names we could alias based on names but // we don't know what's being stored to so kill it all. kill(); } return st; } // return true if this value correspond to the default value of a field. bool is_default_value(Value value) { Constant* con = value->as_Constant(); if (con) { switch (con->type()->tag()) { case intTag: return con->type()->as_IntConstant()->value() == 0; case longTag: return con->type()->as_LongConstant()->value() == 0; case floatTag: return jint_cast(con->type()->as_FloatConstant()->value()) == 0; case doubleTag: return jlong_cast(con->type()->as_DoubleConstant()->value()) == jlong_cast(0); case objectTag: return con->type() == objectNull; default: ShouldNotReachHere(); } } return false; } // return either the actual value of a load or the load itself Value load(LoadField* load) { if (!EliminateFieldAccess) { return load; } if (RoundFPResults && UseSSE < 2 && load->type()->is_float_kind()) { // can't skip load since value might get rounded as a side effect return load; } ciField* field = load->field(); Value object = load->obj(); if (field->holder()->is_loaded() && !field->is_volatile()) { int offset = field->offset(); Value result = NULL; int index = _newobjects.find(object); if (index != -1) { result = _fields.at(index)->at(field); } else if (_objects.at_grow(offset, NULL) == object) { result = _values.at(field); } if (result != NULL) { #ifndef PRODUCT if (PrintIRDuringConstruction && Verbose) { tty->print_cr("Eliminated load: "); load->print_line(); } #endif assert(result->type()->tag() == load->type()->tag(), "wrong types"); return result; } } return load; } // Record this newly allocated object void new_instance(NewInstance* object) { int index = _newobjects.length(); _newobjects.append(object); if (_fields.at_grow(index, NULL) == NULL) { _fields.at_put(index, new FieldBuffer()); } else { _fields.at(index)->kill(); } } void store_value(Value value) { int index = _newobjects.find(value); if (index != -1) { // stored a newly allocated object into another object. // Assume we've lost track of it as separate slice of memory. // We could do better by keeping track of whether individual // fields could alias each other. _newobjects.remove_at(index); // pull out the field info and store it at the end up the list // of field info list to be reused later. _fields.append(_fields.at(index)); _fields.remove_at(index); } } void kill() { _newobjects.trunc_to(0); _objects.trunc_to(0); _values.kill(); } }; // Implementation of GraphBuilder's ScopeData GraphBuilder::ScopeData::ScopeData(ScopeData* parent) : _parent(parent) , _bci2block(NULL) , _scope(NULL) , _has_handler(false) , _stream(NULL) , _work_list(NULL) , _parsing_jsr(false) , _jsr_xhandlers(NULL) , _caller_stack_size(-1) , _continuation(NULL) , _num_returns(0) , _cleanup_block(NULL) , _cleanup_return_prev(NULL) , _cleanup_state(NULL) { if (parent != NULL) { _max_inline_size = (intx) ((float) NestedInliningSizeRatio * (float) parent->max_inline_size() / 100.0f); } else { _max_inline_size = MaxInlineSize; } if (_max_inline_size < MaxTrivialSize) { _max_inline_size = MaxTrivialSize; } } void GraphBuilder::kill_all() { if (UseLocalValueNumbering) { vmap()->kill_all(); } _memory->kill(); } BlockBegin* GraphBuilder::ScopeData::block_at(int bci) { if (parsing_jsr()) { // It is necessary to clone all blocks associated with a // subroutine, including those for exception handlers in the scope // of the method containing the jsr (because those exception // handlers may contain ret instructions in some cases). BlockBegin* block = bci2block()->at(bci); if (block != NULL && block == parent()->bci2block()->at(bci)) { BlockBegin* new_block = new BlockBegin(block->bci()); #ifndef PRODUCT if (PrintInitialBlockList) { tty->print_cr("CFG: cloned block %d (bci %d) as block %d for jsr", block->block_id(), block->bci(), new_block->block_id()); } #endif // copy data from cloned blocked new_block->set_depth_first_number(block->depth_first_number()); if (block->is_set(BlockBegin::parser_loop_header_flag)) new_block->set(BlockBegin::parser_loop_header_flag); // Preserve certain flags for assertion checking if (block->is_set(BlockBegin::subroutine_entry_flag)) new_block->set(BlockBegin::subroutine_entry_flag); if (block->is_set(BlockBegin::exception_entry_flag)) new_block->set(BlockBegin::exception_entry_flag); // copy was_visited_flag to allow early detection of bailouts // if a block that is used in a jsr has already been visited before, // it is shared between the normal control flow and a subroutine // BlockBegin::try_merge returns false when the flag is set, this leads // to a compilation bailout if (block->is_set(BlockBegin::was_visited_flag)) new_block->set(BlockBegin::was_visited_flag); bci2block()->at_put(bci, new_block); block = new_block; } return block; } else { return bci2block()->at(bci); } } XHandlers* GraphBuilder::ScopeData::xhandlers() const { if (_jsr_xhandlers == NULL) { assert(!parsing_jsr(), ""); return scope()->xhandlers(); } assert(parsing_jsr(), ""); return _jsr_xhandlers; } void GraphBuilder::ScopeData::set_scope(IRScope* scope) { _scope = scope; bool parent_has_handler = false; if (parent() != NULL) { parent_has_handler = parent()->has_handler(); } _has_handler = parent_has_handler || scope->xhandlers()->has_handlers(); } void GraphBuilder::ScopeData::set_inline_cleanup_info(BlockBegin* block, Instruction* return_prev, ValueStack* return_state) { _cleanup_block = block; _cleanup_return_prev = return_prev; _cleanup_state = return_state; } void GraphBuilder::ScopeData::add_to_work_list(BlockBegin* block) { if (_work_list == NULL) { _work_list = new BlockList(); } if (!block->is_set(BlockBegin::is_on_work_list_flag)) { // Do not start parsing the continuation block while in a // sub-scope if (parsing_jsr()) { if (block == jsr_continuation()) { return; } } else { if (block == continuation()) { return; } } block->set(BlockBegin::is_on_work_list_flag); _work_list->push(block); sort_top_into_worklist(_work_list, block); } } void GraphBuilder::sort_top_into_worklist(BlockList* worklist, BlockBegin* top) { assert(worklist->top() == top, ""); // sort block descending into work list const int dfn = top->depth_first_number(); assert(dfn != -1, "unknown depth first number"); int i = worklist->length()-2; while (i >= 0) { BlockBegin* b = worklist->at(i); if (b->depth_first_number() < dfn) { worklist->at_put(i+1, b); } else { break; } i --; } if (i >= -1) worklist->at_put(i + 1, top); } BlockBegin* GraphBuilder::ScopeData::remove_from_work_list() { if (is_work_list_empty()) { return NULL; } return _work_list->pop(); } bool GraphBuilder::ScopeData::is_work_list_empty() const { return (_work_list == NULL || _work_list->length() == 0); } void GraphBuilder::ScopeData::setup_jsr_xhandlers() { assert(parsing_jsr(), ""); // clone all the exception handlers from the scope XHandlers* handlers = new XHandlers(scope()->xhandlers()); const int n = handlers->length(); for (int i = 0; i < n; i++) { // The XHandlers need to be adjusted to dispatch to the cloned // handler block instead of the default one but the synthetic // unlocker needs to be handled specially. The synthetic unlocker // should be left alone since there can be only one and all code // should dispatch to the same one. XHandler* h = handlers->handler_at(i); assert(h->handler_bci() != SynchronizationEntryBCI, "must be real"); h->set_entry_block(block_at(h->handler_bci())); } _jsr_xhandlers = handlers; } int GraphBuilder::ScopeData::num_returns() { if (parsing_jsr()) { return parent()->num_returns(); } return _num_returns; } void GraphBuilder::ScopeData::incr_num_returns() { if (parsing_jsr()) { parent()->incr_num_returns(); } else { ++_num_returns; } } // Implementation of GraphBuilder #define INLINE_BAILOUT(msg) { inline_bailout(msg); return false; } void GraphBuilder::load_constant() { ciConstant con = stream()->get_constant(); if (con.basic_type() == T_ILLEGAL) { BAILOUT("could not resolve a constant"); } else { ValueType* t = illegalType; ValueStack* patch_state = NULL; switch (con.basic_type()) { case T_BOOLEAN: t = new IntConstant (con.as_boolean()); break; case T_BYTE : t = new IntConstant (con.as_byte ()); break; case T_CHAR : t = new IntConstant (con.as_char ()); break; case T_SHORT : t = new IntConstant (con.as_short ()); break; case T_INT : t = new IntConstant (con.as_int ()); break; case T_LONG : t = new LongConstant (con.as_long ()); break; case T_FLOAT : t = new FloatConstant (con.as_float ()); break; case T_DOUBLE : t = new DoubleConstant (con.as_double ()); break; case T_ARRAY : t = new ArrayConstant (con.as_object ()->as_array ()); break; case T_OBJECT : { ciObject* obj = con.as_object(); if (!obj->is_loaded() || (PatchALot && obj->klass() != ciEnv::current()->String_klass())) { patch_state = copy_state_before(); t = new ObjectConstant(obj); } else { assert(obj->is_instance(), "must be java_mirror of klass"); t = new InstanceConstant(obj->as_instance()); } break; } default : ShouldNotReachHere(); } Value x; if (patch_state != NULL) { x = new Constant(t, patch_state); } else { x = new Constant(t); } push(t, append(x)); } } void GraphBuilder::load_local(ValueType* type, int index) { Value x = state()->local_at(index); assert(x != NULL && !x->type()->is_illegal(), "access of illegal local variable"); push(type, x); } void GraphBuilder::store_local(ValueType* type, int index) { Value x = pop(type); store_local(state(), x, index); } void GraphBuilder::store_local(ValueStack* state, Value x, int index) { if (parsing_jsr()) { // We need to do additional tracking of the location of the return // address for jsrs since we don't handle arbitrary jsr/ret // constructs. Here we are figuring out in which circumstances we // need to bail out. if (x->type()->is_address()) { scope_data()->set_jsr_return_address_local(index); // Also check parent jsrs (if any) at this time to see whether // they are using this local. We don't handle skipping over a // ret. for (ScopeData* cur_scope_data = scope_data()->parent(); cur_scope_data != NULL && cur_scope_data->parsing_jsr() && cur_scope_data->scope() == scope(); cur_scope_data = cur_scope_data->parent()) { if (cur_scope_data->jsr_return_address_local() == index) { BAILOUT("subroutine overwrites return address from previous subroutine"); } } } else if (index == scope_data()->jsr_return_address_local()) { scope_data()->set_jsr_return_address_local(-1); } } state->store_local(index, round_fp(x)); } void GraphBuilder::load_indexed(BasicType type) { // In case of in block code motion in range check elimination ValueStack* state_before = copy_state_indexed_access(); compilation()->set_has_access_indexed(true); Value index = ipop(); Value array = apop(); Value length = NULL; if (CSEArrayLength || (array->as_AccessField() && array->as_AccessField()->field()->is_constant()) || (array->as_NewArray() && array->as_NewArray()->length() && array->as_NewArray()->length()->type()->is_constant())) { length = append(new ArrayLength(array, state_before)); } push(as_ValueType(type), append(new LoadIndexed(array, index, length, type, state_before))); } void GraphBuilder::store_indexed(BasicType type) { // In case of in block code motion in range check elimination ValueStack* state_before = copy_state_indexed_access(); compilation()->set_has_access_indexed(true); Value value = pop(as_ValueType(type)); Value index = ipop(); Value array = apop(); Value length = NULL; if (CSEArrayLength || (array->as_AccessField() && array->as_AccessField()->field()->is_constant()) || (array->as_NewArray() && array->as_NewArray()->length() && array->as_NewArray()->length()->type()->is_constant())) { length = append(new ArrayLength(array, state_before)); } StoreIndexed* result = new StoreIndexed(array, index, length, type, value, state_before); append(result); _memory->store_value(value); if (type == T_OBJECT && is_profiling()) { // Note that we'd collect profile data in this method if we wanted it. compilation()->set_would_profile(true); if (profile_checkcasts()) { result->set_profiled_method(method()); result->set_profiled_bci(bci()); result->set_should_profile(true); } } } void GraphBuilder::stack_op(Bytecodes::Code code) { switch (code) { case Bytecodes::_pop: { state()->raw_pop(); } break; case Bytecodes::_pop2: { state()->raw_pop(); state()->raw_pop(); } break; case Bytecodes::_dup: { Value w = state()->raw_pop(); state()->raw_push(w); state()->raw_push(w); } break; case Bytecodes::_dup_x1: { Value w1 = state()->raw_pop(); Value w2 = state()->raw_pop(); state()->raw_push(w1); state()->raw_push(w2); state()->raw_push(w1); } break; case Bytecodes::_dup_x2: { Value w1 = state()->raw_pop(); Value w2 = state()->raw_pop(); Value w3 = state()->raw_pop(); state()->raw_push(w1); state()->raw_push(w3); state()->raw_push(w2); state()->raw_push(w1); } break; case Bytecodes::_dup2: { Value w1 = state()->raw_pop(); Value w2 = state()->raw_pop(); state()->raw_push(w2); state()->raw_push(w1); state()->raw_push(w2); state()->raw_push(w1); } break; case Bytecodes::_dup2_x1: { Value w1 = state()->raw_pop(); Value w2 = state()->raw_pop(); Value w3 = state()->raw_pop(); state()->raw_push(w2); state()->raw_push(w1); state()->raw_push(w3); state()->raw_push(w2); state()->raw_push(w1); } break; case Bytecodes::_dup2_x2: { Value w1 = state()->raw_pop(); Value w2 = state()->raw_pop(); Value w3 = state()->raw_pop(); Value w4 = state()->raw_pop(); state()->raw_push(w2); state()->raw_push(w1); state()->raw_push(w4); state()->raw_push(w3); state()->raw_push(w2); state()->raw_push(w1); } break; case Bytecodes::_swap: { Value w1 = state()->raw_pop(); Value w2 = state()->raw_pop(); state()->raw_push(w1); state()->raw_push(w2); } break; default: ShouldNotReachHere(); break; } } void GraphBuilder::arithmetic_op(ValueType* type, Bytecodes::Code code, ValueStack* state_before) { Value y = pop(type); Value x = pop(type); // NOTE: strictfp can be queried from current method since we don't // inline methods with differing strictfp bits Value res = new ArithmeticOp(code, x, y, method()->is_strict(), state_before); // Note: currently single-precision floating-point rounding on Intel is handled at the LIRGenerator level res = append(res); if (method()->is_strict()) { res = round_fp(res); } push(type, res); } void GraphBuilder::negate_op(ValueType* type) { push(type, append(new NegateOp(pop(type)))); } void GraphBuilder::shift_op(ValueType* type, Bytecodes::Code code) { Value s = ipop(); Value x = pop(type); // try to simplify // Note: This code should go into the canonicalizer as soon as it can // can handle canonicalized forms that contain more than one node. if (CanonicalizeNodes && code == Bytecodes::_iushr) { // pattern: x >>> s IntConstant* s1 = s->type()->as_IntConstant(); if (s1 != NULL) { // pattern: x >>> s1, with s1 constant ShiftOp* l = x->as_ShiftOp(); if (l != NULL && l->op() == Bytecodes::_ishl) { // pattern: (a << b) >>> s1 IntConstant* s0 = l->y()->type()->as_IntConstant(); if (s0 != NULL) { // pattern: (a << s0) >>> s1 const int s0c = s0->value() & 0x1F; // only the low 5 bits are significant for shifts const int s1c = s1->value() & 0x1F; // only the low 5 bits are significant for shifts if (s0c == s1c) { if (s0c == 0) { // pattern: (a << 0) >>> 0 => simplify to: a ipush(l->x()); } else { // pattern: (a << s0c) >>> s0c => simplify to: a & m, with m constant assert(0 < s0c && s0c < BitsPerInt, "adjust code below to handle corner cases"); const int m = (1 << (BitsPerInt - s0c)) - 1; Value s = append(new Constant(new IntConstant(m))); ipush(append(new LogicOp(Bytecodes::_iand, l->x(), s))); } return; } } } } } // could not simplify push(type, append(new ShiftOp(code, x, s))); } void GraphBuilder::logic_op(ValueType* type, Bytecodes::Code code) { Value y = pop(type); Value x = pop(type); push(type, append(new LogicOp(code, x, y))); } void GraphBuilder::compare_op(ValueType* type, Bytecodes::Code code) { ValueStack* state_before = copy_state_before(); Value y = pop(type); Value x = pop(type); ipush(append(new CompareOp(code, x, y, state_before))); } void GraphBuilder::convert(Bytecodes::Code op, BasicType from, BasicType to) { push(as_ValueType(to), append(new Convert(op, pop(as_ValueType(from)), as_ValueType(to)))); } void GraphBuilder::increment() { int index = stream()->get_index(); int delta = stream()->is_wide() ? (signed short)Bytes::get_Java_u2(stream()->cur_bcp() + 4) : (signed char)(stream()->cur_bcp()[2]); load_local(intType, index); ipush(append(new Constant(new IntConstant(delta)))); arithmetic_op(intType, Bytecodes::_iadd); store_local(intType, index); } void GraphBuilder::_goto(int from_bci, int to_bci) { Goto *x = new Goto(block_at(to_bci), to_bci <= from_bci); if (is_profiling()) { compilation()->set_would_profile(true); x->set_profiled_bci(bci()); if (profile_branches()) { x->set_profiled_method(method()); x->set_should_profile(true); } } append(x); } void GraphBuilder::if_node(Value x, If::Condition cond, Value y, ValueStack* state_before) { BlockBegin* tsux = block_at(stream()->get_dest()); BlockBegin* fsux = block_at(stream()->next_bci()); bool is_bb = tsux->bci() < stream()->cur_bci() || fsux->bci() < stream()->cur_bci(); // In case of loop invariant code motion or predicate insertion // before the body of a loop the state is needed Instruction *i = append(new If(x, cond, false, y, tsux, fsux, (is_bb || compilation()->is_optimistic()) ? state_before : NULL, is_bb)); assert(i->as_Goto() == NULL || (i->as_Goto()->sux_at(0) == tsux && i->as_Goto()->is_safepoint() == tsux->bci() < stream()->cur_bci()) || (i->as_Goto()->sux_at(0) == fsux && i->as_Goto()->is_safepoint() == fsux->bci() < stream()->cur_bci()), "safepoint state of Goto returned by canonicalizer incorrect"); if (is_profiling()) { If* if_node = i->as_If(); if (if_node != NULL) { // Note that we'd collect profile data in this method if we wanted it. compilation()->set_would_profile(true); // At level 2 we need the proper bci to count backedges if_node->set_profiled_bci(bci()); if (profile_branches()) { // Successors can be rotated by the canonicalizer, check for this case. if_node->set_profiled_method(method()); if_node->set_should_profile(true); if (if_node->tsux() == fsux) { if_node->set_swapped(true); } } return; } // Check if this If was reduced to Goto. Goto *goto_node = i->as_Goto(); if (goto_node != NULL) { compilation()->set_would_profile(true); goto_node->set_profiled_bci(bci()); if (profile_branches()) { goto_node->set_profiled_method(method()); goto_node->set_should_profile(true); // Find out which successor is used. if (goto_node->default_sux() == tsux) { goto_node->set_direction(Goto::taken); } else if (goto_node->default_sux() == fsux) { goto_node->set_direction(Goto::not_taken); } else { ShouldNotReachHere(); } } return; } } } void GraphBuilder::if_zero(ValueType* type, If::Condition cond) { Value y = append(new Constant(intZero)); ValueStack* state_before = copy_state_before(); Value x = ipop(); if_node(x, cond, y, state_before); } void GraphBuilder::if_null(ValueType* type, If::Condition cond) { Value y = append(new Constant(objectNull)); ValueStack* state_before = copy_state_before(); Value x = apop(); if_node(x, cond, y, state_before); } void GraphBuilder::if_same(ValueType* type, If::Condition cond) { ValueStack* state_before = copy_state_before(); Value y = pop(type); Value x = pop(type); if_node(x, cond, y, state_before); } void GraphBuilder::jsr(int dest) { // We only handle well-formed jsrs (those which are "block-structured"). // If the bytecodes are strange (jumping out of a jsr block) then we // might end up trying to re-parse a block containing a jsr which // has already been activated. Watch for this case and bail out. for (ScopeData* cur_scope_data = scope_data(); cur_scope_data != NULL && cur_scope_data->parsing_jsr() && cur_scope_data->scope() == scope(); cur_scope_data = cur_scope_data->parent()) { if (cur_scope_data->jsr_entry_bci() == dest) { BAILOUT("too-complicated jsr/ret structure"); } } push(addressType, append(new Constant(new AddressConstant(next_bci())))); if (!try_inline_jsr(dest)) { return; // bailed out while parsing and inlining subroutine } } void GraphBuilder::ret(int local_index) { if (!parsing_jsr()) BAILOUT("ret encountered while not parsing subroutine"); if (local_index != scope_data()->jsr_return_address_local()) { BAILOUT("can not handle complicated jsr/ret constructs"); } // Rets simply become (NON-SAFEPOINT) gotos to the jsr continuation append(new Goto(scope_data()->jsr_continuation(), false)); } void GraphBuilder::table_switch() { Bytecode_tableswitch sw(stream()); const int l = sw.length(); if (CanonicalizeNodes && l == 1) { // total of 2 successors => use If instead of switch // Note: This code should go into the canonicalizer as soon as it can // can handle canonicalized forms that contain more than one node. Value key = append(new Constant(new IntConstant(sw.low_key()))); BlockBegin* tsux = block_at(bci() + sw.dest_offset_at(0)); BlockBegin* fsux = block_at(bci() + sw.default_offset()); bool is_bb = tsux->bci() < bci() || fsux->bci() < bci(); // In case of loop invariant code motion or predicate insertion // before the body of a loop the state is needed ValueStack* state_before = copy_state_if_bb(is_bb); append(new If(ipop(), If::eql, true, key, tsux, fsux, state_before, is_bb)); } else { // collect successors BlockList* sux = new BlockList(l + 1, NULL); int i; bool has_bb = false; for (i = 0; i < l; i++) { sux->at_put(i, block_at(bci() + sw.dest_offset_at(i))); if (sw.dest_offset_at(i) < 0) has_bb = true; } // add default successor if (sw.default_offset() < 0) has_bb = true; sux->at_put(i, block_at(bci() + sw.default_offset())); // In case of loop invariant code motion or predicate insertion // before the body of a loop the state is needed ValueStack* state_before = copy_state_if_bb(has_bb); Instruction* res = append(new TableSwitch(ipop(), sux, sw.low_key(), state_before, has_bb)); #ifdef ASSERT if (res->as_Goto()) { for (i = 0; i < l; i++) { if (sux->at(i) == res->as_Goto()->sux_at(0)) { assert(res->as_Goto()->is_safepoint() == sw.dest_offset_at(i) < 0, "safepoint state of Goto returned by canonicalizer incorrect"); } } } #endif } } void GraphBuilder::lookup_switch() { Bytecode_lookupswitch sw(stream()); const int l = sw.number_of_pairs(); if (CanonicalizeNodes && l == 1) { // total of 2 successors => use If instead of switch // Note: This code should go into the canonicalizer as soon as it can // can handle canonicalized forms that contain more than one node. // simplify to If LookupswitchPair pair = sw.pair_at(0); Value key = append(new Constant(new IntConstant(pair.match()))); BlockBegin* tsux = block_at(bci() + pair.offset()); BlockBegin* fsux = block_at(bci() + sw.default_offset()); bool is_bb = tsux->bci() < bci() || fsux->bci() < bci(); // In case of loop invariant code motion or predicate insertion // before the body of a loop the state is needed ValueStack* state_before = copy_state_if_bb(is_bb);; append(new If(ipop(), If::eql, true, key, tsux, fsux, state_before, is_bb)); } else { // collect successors & keys BlockList* sux = new BlockList(l + 1, NULL); intArray* keys = new intArray(l, 0); int i; bool has_bb = false; for (i = 0; i < l; i++) { LookupswitchPair pair = sw.pair_at(i); if (pair.offset() < 0) has_bb = true; sux->at_put(i, block_at(bci() + pair.offset())); keys->at_put(i, pair.match()); } // add default successor if (sw.default_offset() < 0) has_bb = true; sux->at_put(i, block_at(bci() + sw.default_offset())); // In case of loop invariant code motion or predicate insertion // before the body of a loop the state is needed ValueStack* state_before = copy_state_if_bb(has_bb); Instruction* res = append(new LookupSwitch(ipop(), sux, keys, state_before, has_bb)); #ifdef ASSERT if (res->as_Goto()) { for (i = 0; i < l; i++) { if (sux->at(i) == res->as_Goto()->sux_at(0)) { assert(res->as_Goto()->is_safepoint() == sw.pair_at(i).offset() < 0, "safepoint state of Goto returned by canonicalizer incorrect"); } } } #endif } } void GraphBuilder::call_register_finalizer() { // If the receiver requires finalization then emit code to perform // the registration on return. // Gather some type information about the receiver Value receiver = state()->local_at(0); assert(receiver != NULL, "must have a receiver"); ciType* declared_type = receiver->declared_type(); ciType* exact_type = receiver->exact_type(); if (exact_type == NULL && receiver->as_Local() && receiver->as_Local()->java_index() == 0) { ciInstanceKlass* ik = compilation()->method()->holder(); if (ik->is_final()) { exact_type = ik; } else if (UseCHA && !(ik->has_subklass() || ik->is_interface())) { // test class is leaf class compilation()->dependency_recorder()->assert_leaf_type(ik); exact_type = ik; } else { declared_type = ik; } } // see if we know statically that registration isn't required bool needs_check = true; if (exact_type != NULL) { needs_check = exact_type->as_instance_klass()->has_finalizer(); } else if (declared_type != NULL) { ciInstanceKlass* ik = declared_type->as_instance_klass(); if (!Dependencies::has_finalizable_subclass(ik)) { compilation()->dependency_recorder()->assert_has_no_finalizable_subclasses(ik); needs_check = false; } } if (needs_check) { // Perform the registration of finalizable objects. ValueStack* state_before = copy_state_for_exception(); load_local(objectType, 0); append_split(new Intrinsic(voidType, vmIntrinsics::_Object_init, state()->pop_arguments(1), true, state_before, true)); } } void GraphBuilder::method_return(Value x) { if (RegisterFinalizersAtInit && method()->intrinsic_id() == vmIntrinsics::_Object_init) { call_register_finalizer(); } bool need_mem_bar = false; if (method()->name() == ciSymbol::object_initializer_name() && scope()->wrote_final()) { need_mem_bar = true; } // Check to see whether we are inlining. If so, Return // instructions become Gotos to the continuation point. if (continuation() != NULL) { assert(!method()->is_synchronized() || InlineSynchronizedMethods, "can not inline synchronized methods yet"); if (compilation()->env()->dtrace_method_probes()) { // Report exit from inline methods Values* args = new Values(1); args->push(append(new Constant(new MethodConstant(method())))); append(new RuntimeCall(voidType, "dtrace_method_exit", CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit), args)); } // If the inlined method is synchronized, the monitor must be // released before we jump to the continuation block. if (method()->is_synchronized()) { assert(state()->locks_size() == 1, "receiver must be locked here"); monitorexit(state()->lock_at(0), SynchronizationEntryBCI); } if (need_mem_bar) { append(new MemBar(lir_membar_storestore)); } // State at end of inlined method is the state of the caller // without the method parameters on stack, including the // return value, if any, of the inlined method on operand stack. int invoke_bci = state()->caller_state()->bci(); set_state(state()->caller_state()->copy_for_parsing()); if (x != NULL) { state()->push(x->type(), x); if (profile_return() && x->type()->is_object_kind()) { ciMethod* caller = state()->scope()->method(); ciMethodData* md = caller->method_data_or_null(); ciProfileData* data = md->bci_to_data(invoke_bci); if (data->is_CallTypeData() || data->is_VirtualCallTypeData()) { bool has_return = data->is_CallTypeData() ? ((ciCallTypeData*)data)->has_return() : ((ciVirtualCallTypeData*)data)->has_return(); // May not be true in case of an inlined call through a method handle intrinsic. if (has_return) { profile_return_type(x, method(), caller, invoke_bci); } } } } Goto* goto_callee = new Goto(continuation(), false); // See whether this is the first return; if so, store off some // of the state for later examination if (num_returns() == 0) { set_inline_cleanup_info(); } // The current bci() is in the wrong scope, so use the bci() of // the continuation point. append_with_bci(goto_callee, scope_data()->continuation()->bci()); incr_num_returns(); return; } state()->truncate_stack(0); if (method()->is_synchronized()) { // perform the unlocking before exiting the method Value receiver; if (!method()->is_static()) { receiver = _initial_state->local_at(0); } else { receiver = append(new Constant(new ClassConstant(method()->holder()))); } append_split(new MonitorExit(receiver, state()->unlock())); } if (need_mem_bar) { append(new MemBar(lir_membar_storestore)); } append(new Return(x)); } void GraphBuilder::access_field(Bytecodes::Code code) { bool will_link; ciField* field = stream()->get_field(will_link); ciInstanceKlass* holder = field->holder(); BasicType field_type = field->type()->basic_type(); ValueType* type = as_ValueType(field_type); // call will_link again to determine if the field is valid. const bool needs_patching = !holder->is_loaded() || !field->will_link(method()->holder(), code) || PatchALot; ValueStack* state_before = NULL; if (!holder->is_initialized() || needs_patching) { // save state before instruction for debug info when // deoptimization happens during patching state_before = copy_state_before(); } Value obj = NULL; if (code == Bytecodes::_getstatic || code == Bytecodes::_putstatic) { if (state_before != NULL) { // build a patching constant obj = new Constant(new InstanceConstant(holder->java_mirror()), state_before); } else { obj = new Constant(new InstanceConstant(holder->java_mirror())); } } if (field->is_final() && (code == Bytecodes::_putfield)) { scope()->set_wrote_final(); } const int offset = !needs_patching ? field->offset() : -1; switch (code) { case Bytecodes::_getstatic: { // check for compile-time constants, i.e., initialized static final fields Instruction* constant = NULL; if (field->is_constant() && !PatchALot) { ciConstant field_val = field->constant_value(); BasicType field_type = field_val.basic_type(); switch (field_type) { case T_ARRAY: case T_OBJECT: if (field_val.as_object()->should_be_constant()) { constant = new Constant(as_ValueType(field_val)); } break; default: constant = new Constant(as_ValueType(field_val)); } } if (constant != NULL) { push(type, append(constant)); } else { if (state_before == NULL) { state_before = copy_state_for_exception(); } push(type, append(new LoadField(append(obj), offset, field, true, state_before, needs_patching))); } break; } case Bytecodes::_putstatic: { Value val = pop(type); if (state_before == NULL) { state_before = copy_state_for_exception(); } append(new StoreField(append(obj), offset, field, val, true, state_before, needs_patching)); } break; case Bytecodes::_getfield: { // Check for compile-time constants, i.e., trusted final non-static fields. Instruction* constant = NULL; obj = apop(); ObjectType* obj_type = obj->type()->as_ObjectType(); if (obj_type->is_constant() && !PatchALot) { ciObject* const_oop = obj_type->constant_value(); if (!const_oop->is_null_object() && const_oop->is_loaded()) { if (field->is_constant()) { ciConstant field_val = field->constant_value_of(const_oop); BasicType field_type = field_val.basic_type(); switch (field_type) { case T_ARRAY: case T_OBJECT: if (field_val.as_object()->should_be_constant()) { constant = new Constant(as_ValueType(field_val)); } break; default: constant = new Constant(as_ValueType(field_val)); } } else { // For CallSite objects treat the target field as a compile time constant. if (const_oop->is_call_site()) { ciCallSite* call_site = const_oop->as_call_site(); if (field->is_call_site_target()) { ciMethodHandle* target = call_site->get_target(); if (target != NULL) { // just in case ciConstant field_val(T_OBJECT, target); constant = new Constant(as_ValueType(field_val)); // Add a dependence for invalidation of the optimization. if (!call_site->is_constant_call_site()) { dependency_recorder()->assert_call_site_target_value(call_site, target); } } } } } } } if (constant != NULL) { push(type, append(constant)); } else { if (state_before == NULL) { state_before = copy_state_for_exception(); } LoadField* load = new LoadField(obj, offset, field, false, state_before, needs_patching); Value replacement = !needs_patching ? _memory->load(load) : load; if (replacement != load) { assert(replacement->is_linked() || !replacement->can_be_linked(), "should already by linked"); push(type, replacement); } else { push(type, append(load)); } } break; } case Bytecodes::_putfield: { Value val = pop(type); obj = apop(); if (state_before == NULL) { state_before = copy_state_for_exception(); } StoreField* store = new StoreField(obj, offset, field, val, false, state_before, needs_patching); if (!needs_patching) store = _memory->store(store); if (store != NULL) { append(store); } break; } default: ShouldNotReachHere(); break; } } Dependencies* GraphBuilder::dependency_recorder() const { assert(DeoptC1, "need debug information"); return compilation()->dependency_recorder(); } // How many arguments do we want to profile? Values* GraphBuilder::args_list_for_profiling(ciMethod* target, int& start, bool may_have_receiver) { int n = 0; bool has_receiver = may_have_receiver && Bytecodes::has_receiver(method()->java_code_at_bci(bci())); start = has_receiver ? 1 : 0; if (profile_arguments()) { ciProfileData* data = method()->method_data()->bci_to_data(bci()); if (data->is_CallTypeData() || data->is_VirtualCallTypeData()) { n = data->is_CallTypeData() ? data->as_CallTypeData()->number_of_arguments() : data->as_VirtualCallTypeData()->number_of_arguments(); } } // If we are inlining then we need to collect arguments to profile parameters for the target if (profile_parameters() && target != NULL) { if (target->method_data() != NULL && target->method_data()->parameters_type_data() != NULL) { // The receiver is profiled on method entry so it's included in // the number of parameters but here we're only interested in // actual arguments. n = MAX2(n, target->method_data()->parameters_type_data()->number_of_parameters() - start); } } if (n > 0) { return new Values(n); } return NULL; } // Collect arguments that we want to profile in a list Values* GraphBuilder::collect_args_for_profiling(Values* args, ciMethod* target, bool may_have_receiver) { int start = 0; Values* obj_args = args_list_for_profiling(target, start, may_have_receiver); if (obj_args == NULL) { return NULL; } int s = obj_args->size(); for (int i = start, j = 0; j < s; i++) { if (args->at(i)->type()->is_object_kind()) { obj_args->push(args->at(i)); j++; } } assert(s == obj_args->length(), "missed on arg?"); return obj_args; } void GraphBuilder::invoke(Bytecodes::Code code) { bool will_link; ciSignature* declared_signature = NULL; ciMethod* target = stream()->get_method(will_link, &declared_signature); ciKlass* holder = stream()->get_declared_method_holder(); const Bytecodes::Code bc_raw = stream()->cur_bc_raw(); assert(declared_signature != NULL, "cannot be null"); if (!C1PatchInvokeDynamic && Bytecodes::has_optional_appendix(bc_raw) && !will_link) { BAILOUT("unlinked call site (C1PatchInvokeDynamic is off)"); } // we have to make sure the argument size (incl. the receiver) // is correct for compilation (the call would fail later during // linkage anyway) - was bug (gri 7/28/99) { // Use raw to get rewritten bytecode. const bool is_invokestatic = bc_raw == Bytecodes::_invokestatic; const bool allow_static = is_invokestatic || bc_raw == Bytecodes::_invokehandle || bc_raw == Bytecodes::_invokedynamic; if (target->is_loaded()) { if (( target->is_static() && !allow_static) || (!target->is_static() && is_invokestatic)) { BAILOUT("will cause link error"); } } } ciInstanceKlass* klass = target->holder(); // check if CHA possible: if so, change the code to invoke_special ciInstanceKlass* calling_klass = method()->holder(); ciInstanceKlass* callee_holder = ciEnv::get_instance_klass_for_declared_method_holder(holder); ciInstanceKlass* actual_recv = callee_holder; CompileLog* log = compilation()->log(); if (log != NULL) log->elem("call method='%d' instr='%s'", log->identify(target), Bytecodes::name(code)); // Some methods are obviously bindable without any type checks so // convert them directly to an invokespecial or invokestatic. if (target->is_loaded() && !target->is_abstract() && target->can_be_statically_bound()) { switch (bc_raw) { case Bytecodes::_invokevirtual: code = Bytecodes::_invokespecial; break; case Bytecodes::_invokehandle: code = target->is_static() ? Bytecodes::_invokestatic : Bytecodes::_invokespecial; break; } } else { if (bc_raw == Bytecodes::_invokehandle) { assert(!will_link, "should come here only for unlinked call"); code = Bytecodes::_invokespecial; } } // Push appendix argument (MethodType, CallSite, etc.), if one. bool patch_for_appendix = false; int patching_appendix_arg = 0; if (C1PatchInvokeDynamic && (Bytecodes::has_optional_appendix(bc_raw) && (!will_link || PatchALot))) { Value arg = append(new Constant(new ObjectConstant(compilation()->env()->unloaded_ciinstance()), copy_state_before())); apush(arg); patch_for_appendix = true; patching_appendix_arg = (will_link && stream()->has_appendix()) ? 0 : 1; } else if (stream()->has_appendix()) { ciObject* appendix = stream()->get_appendix(); Value arg = append(new Constant(new ObjectConstant(appendix))); apush(arg); } // NEEDS_CLEANUP // I've added the target->is_loaded() test below but I don't really understand // how klass->is_loaded() can be true and yet target->is_loaded() is false. // this happened while running the JCK invokevirtual tests under doit. TKR ciMethod* cha_monomorphic_target = NULL; ciMethod* exact_target = NULL; Value better_receiver = NULL; if (UseCHA && DeoptC1 && klass->is_loaded() && target->is_loaded() && !(// %%% FIXME: Are both of these relevant? target->is_method_handle_intrinsic() || target->is_compiled_lambda_form()) && !patch_for_appendix) { Value receiver = NULL; ciInstanceKlass* receiver_klass = NULL; bool type_is_exact = false; // try to find a precise receiver type if (will_link && !target->is_static()) { int index = state()->stack_size() - (target->arg_size_no_receiver() + 1); receiver = state()->stack_at(index); ciType* type = receiver->exact_type(); if (type != NULL && type->is_loaded() && type->is_instance_klass() && !type->as_instance_klass()->is_interface()) { receiver_klass = (ciInstanceKlass*) type; type_is_exact = true; } if (type == NULL) { type = receiver->declared_type(); if (type != NULL && type->is_loaded() && type->is_instance_klass() && !type->as_instance_klass()->is_interface()) { receiver_klass = (ciInstanceKlass*) type; if (receiver_klass->is_leaf_type() && !receiver_klass->is_final()) { // Insert a dependency on this type since // find_monomorphic_target may assume it's already done. dependency_recorder()->assert_leaf_type(receiver_klass); type_is_exact = true; } } } } if (receiver_klass != NULL && type_is_exact && receiver_klass->is_loaded() && code != Bytecodes::_invokespecial) { // If we have the exact receiver type we can bind directly to // the method to call. exact_target = target->resolve_invoke(calling_klass, receiver_klass); if (exact_target != NULL) { target = exact_target; code = Bytecodes::_invokespecial; } } if (receiver_klass != NULL && receiver_klass->is_subtype_of(actual_recv) && actual_recv->is_initialized()) { actual_recv = receiver_klass; } if ((code == Bytecodes::_invokevirtual && callee_holder->is_initialized()) || (code == Bytecodes::_invokeinterface && callee_holder->is_initialized() && !actual_recv->is_interface())) { // Use CHA on the receiver to select a more precise method. cha_monomorphic_target = target->find_monomorphic_target(calling_klass, callee_holder, actual_recv); } else if (code == Bytecodes::_invokeinterface && callee_holder->is_loaded() && receiver != NULL) { // if there is only one implementor of this interface then we // may be able bind this invoke directly to the implementing // klass but we need both a dependence on the single interface // and on the method we bind to. Additionally since all we know // about the receiver type is the it's supposed to implement the // interface we have to insert a check that it's the class we // expect. Interface types are not checked by the verifier so // they are roughly equivalent to Object. ciInstanceKlass* singleton = NULL; if (target->holder()->nof_implementors() == 1) { singleton = target->holder()->implementor(); assert(singleton != NULL && singleton != target->holder(), "just checking"); assert(holder->is_interface(), "invokeinterface to non interface?"); ciInstanceKlass* decl_interface = (ciInstanceKlass*)holder; // the number of implementors for decl_interface is less or // equal to the number of implementors for target->holder() so // if number of implementors of target->holder() == 1 then // number of implementors for decl_interface is 0 or 1. If // it's 0 then no class implements decl_interface and there's // no point in inlining. if (!holder->is_loaded() || decl_interface->nof_implementors() != 1 || decl_interface->has_default_methods()) { singleton = NULL; } } if (singleton) { cha_monomorphic_target = target->find_monomorphic_target(calling_klass, target->holder(), singleton); if (cha_monomorphic_target != NULL) { // If CHA is able to bind this invoke then update the class // to match that class, otherwise klass will refer to the // interface. klass = cha_monomorphic_target->holder(); actual_recv = target->holder(); // insert a check it's really the expected class. CheckCast* c = new CheckCast(klass, receiver, copy_state_for_exception()); c->set_incompatible_class_change_check(); c->set_direct_compare(klass->is_final()); // pass the result of the checkcast so that the compiler has // more accurate type info in the inlinee better_receiver = append_split(c); } } } } if (cha_monomorphic_target != NULL) { if (cha_monomorphic_target->is_abstract()) { // Do not optimize for abstract methods cha_monomorphic_target = NULL; } } if (cha_monomorphic_target != NULL) { if (!(target->is_final_method())) { // If we inlined because CHA revealed only a single target method, // then we are dependent on that target method not getting overridden // by dynamic class loading. Be sure to test the "static" receiver // dest_method here, as opposed to the actual receiver, which may // falsely lead us to believe that the receiver is final or private. dependency_recorder()->assert_unique_concrete_method(actual_recv, cha_monomorphic_target); } code = Bytecodes::_invokespecial; } // check if we could do inlining if (!PatchALot && Inline && klass->is_loaded() && (klass->is_initialized() || klass->is_interface() && target->holder()->is_initialized()) && target->is_loaded() && !patch_for_appendix) { // callee is known => check if we have static binding assert(target->is_loaded(), "callee must be known"); if (code == Bytecodes::_invokestatic || code == Bytecodes::_invokespecial || code == Bytecodes::_invokevirtual && target->is_final_method() || code == Bytecodes::_invokedynamic) { ciMethod* inline_target = (cha_monomorphic_target != NULL) ? cha_monomorphic_target : target; // static binding => check if callee is ok bool success = try_inline(inline_target, (cha_monomorphic_target != NULL) || (exact_target != NULL), code, better_receiver); CHECK_BAILOUT(); clear_inline_bailout(); if (success) { // Register dependence if JVMTI has either breakpoint // setting or hotswapping of methods capabilities since they may // cause deoptimization. if (compilation()->env()->jvmti_can_hotswap_or_post_breakpoint()) { dependency_recorder()->assert_evol_method(inline_target); } return; } } else { print_inlining(target, "no static binding", /*success*/ false); } } else { print_inlining(target, "not inlineable", /*success*/ false); } // If we attempted an inline which did not succeed because of a // bailout during construction of the callee graph, the entire // compilation has to be aborted. This is fairly rare and currently // seems to only occur for jasm-generated classes which contain // jsr/ret pairs which are not associated with finally clauses and // do not have exception handlers in the containing method, and are // therefore not caught early enough to abort the inlining without // corrupting the graph. (We currently bail out with a non-empty // stack at a ret in these situations.) CHECK_BAILOUT(); // inlining not successful => standard invoke bool is_loaded = target->is_loaded(); ValueType* result_type = as_ValueType(declared_signature->return_type()); ValueStack* state_before = copy_state_exhandling(); // The bytecode (code) might change in this method so we are checking this very late. const bool has_receiver = code == Bytecodes::_invokespecial || code == Bytecodes::_invokevirtual || code == Bytecodes::_invokeinterface; Values* args = state()->pop_arguments(target->arg_size_no_receiver() + patching_appendix_arg); Value recv = has_receiver ? apop() : NULL; int vtable_index = Method::invalid_vtable_index; #ifdef SPARC // Currently only supported on Sparc. // The UseInlineCaches only controls dispatch to invokevirtuals for // loaded classes which we weren't able to statically bind. if (!UseInlineCaches && is_loaded && code == Bytecodes::_invokevirtual && !target->can_be_statically_bound()) { // Find a vtable index if one is available vtable_index = target->resolve_vtable_index(calling_klass, callee_holder); } #endif if (recv != NULL && (code == Bytecodes::_invokespecial || !is_loaded || target->is_final())) { // invokespecial always needs a NULL check. invokevirtual where // the target is final or where it's not known that whether the // target is final requires a NULL check. Otherwise normal // invokevirtual will perform the null check during the lookup // logic or the unverified entry point. Profiling of calls // requires that the null check is performed in all cases. null_check(recv); } if (is_profiling()) { if (recv != NULL && profile_calls()) { null_check(recv); } // Note that we'd collect profile data in this method if we wanted it. compilation()->set_would_profile(true); if (profile_calls()) { assert(cha_monomorphic_target == NULL || exact_target == NULL, "both can not be set"); ciKlass* target_klass = NULL; if (cha_monomorphic_target != NULL) { target_klass = cha_monomorphic_target->holder(); } else if (exact_target != NULL) { target_klass = exact_target->holder(); } profile_call(target, recv, target_klass, collect_args_for_profiling(args, NULL, false), false); } } Invoke* result = new Invoke(code, result_type, recv, args, vtable_index, target, state_before); // push result append_split(result); if (result_type != voidType) { if (method()->is_strict()) { push(result_type, round_fp(result)); } else { push(result_type, result); } } if (profile_return() && result_type->is_object_kind()) { profile_return_type(result, target); } } void GraphBuilder::new_instance(int klass_index) { ValueStack* state_before = copy_state_exhandling(); bool will_link; ciKlass* klass = stream()->get_klass(will_link); assert(klass->is_instance_klass(), "must be an instance klass"); NewInstance* new_instance = new NewInstance(klass->as_instance_klass(), state_before); _memory->new_instance(new_instance); apush(append_split(new_instance)); } void GraphBuilder::new_type_array() { ValueStack* state_before = copy_state_exhandling(); apush(append_split(new NewTypeArray(ipop(), (BasicType)stream()->get_index(), state_before))); } void GraphBuilder::new_object_array() { bool will_link; ciKlass* klass = stream()->get_klass(will_link); ValueStack* state_before = !klass->is_loaded() || PatchALot ? copy_state_before() : copy_state_exhandling(); NewArray* n = new NewObjectArray(klass, ipop(), state_before); apush(append_split(n)); } bool GraphBuilder::direct_compare(ciKlass* k) { if (k->is_loaded() && k->is_instance_klass() && !UseSlowPath) { ciInstanceKlass* ik = k->as_instance_klass(); if (ik->is_final()) { return true; } else { if (DeoptC1 && UseCHA && !(ik->has_subklass() || ik->is_interface())) { // test class is leaf class dependency_recorder()->assert_leaf_type(ik); return true; } } } return false; } void GraphBuilder::check_cast(int klass_index) { bool will_link; ciKlass* klass = stream()->get_klass(will_link); ValueStack* state_before = !klass->is_loaded() || PatchALot ? copy_state_before() : copy_state_for_exception(); CheckCast* c = new CheckCast(klass, apop(), state_before); apush(append_split(c)); c->set_direct_compare(direct_compare(klass)); if (is_profiling()) { // Note that we'd collect profile data in this method if we wanted it. compilation()->set_would_profile(true); if (profile_checkcasts()) { c->set_profiled_method(method()); c->set_profiled_bci(bci()); c->set_should_profile(true); } } } void GraphBuilder::instance_of(int klass_index) { bool will_link; ciKlass* klass = stream()->get_klass(will_link); ValueStack* state_before = !klass->is_loaded() || PatchALot ? copy_state_before() : copy_state_exhandling(); InstanceOf* i = new InstanceOf(klass, apop(), state_before); ipush(append_split(i)); i->set_direct_compare(direct_compare(klass)); if (is_profiling()) { // Note that we'd collect profile data in this method if we wanted it. compilation()->set_would_profile(true); if (profile_checkcasts()) { i->set_profiled_method(method()); i->set_profiled_bci(bci()); i->set_should_profile(true); } } } void GraphBuilder::monitorenter(Value x, int bci) { // save state before locking in case of deoptimization after a NullPointerException ValueStack* state_before = copy_state_for_exception_with_bci(bci); append_with_bci(new MonitorEnter(x, state()->lock(x), state_before), bci); kill_all(); } void GraphBuilder::monitorexit(Value x, int bci) { append_with_bci(new MonitorExit(x, state()->unlock()), bci); kill_all(); } void GraphBuilder::new_multi_array(int dimensions) { bool will_link; ciKlass* klass = stream()->get_klass(will_link); ValueStack* state_before = !klass->is_loaded() || PatchALot ? copy_state_before() : copy_state_exhandling(); Values* dims = new Values(dimensions, NULL); // fill in all dimensions int i = dimensions; while (i-- > 0) dims->at_put(i, ipop()); // create array NewArray* n = new NewMultiArray(klass, dims, state_before); apush(append_split(n)); } void GraphBuilder::throw_op(int bci) { // We require that the debug info for a Throw be the "state before" // the Throw (i.e., exception oop is still on TOS) ValueStack* state_before = copy_state_before_with_bci(bci); Throw* t = new Throw(apop(), state_before); // operand stack not needed after a throw state()->truncate_stack(0); append_with_bci(t, bci); } Value GraphBuilder::round_fp(Value fp_value) { // no rounding needed if SSE2 is used if (RoundFPResults && UseSSE < 2) { // Must currently insert rounding node for doubleword values that // are results of expressions (i.e., not loads from memory or // constants) if (fp_value->type()->tag() == doubleTag && fp_value->as_Constant() == NULL && fp_value->as_Local() == NULL && // method parameters need no rounding fp_value->as_RoundFP() == NULL) { return append(new RoundFP(fp_value)); } } return fp_value; } Instruction* GraphBuilder::append_with_bci(Instruction* instr, int bci) { Canonicalizer canon(compilation(), instr, bci); Instruction* i1 = canon.canonical(); if (i1->is_linked() || !i1->can_be_linked()) { // Canonicalizer returned an instruction which was already // appended so simply return it. return i1; } if (UseLocalValueNumbering) { // Lookup the instruction in the ValueMap and add it to the map if // it's not found. Instruction* i2 = vmap()->find_insert(i1); if (i2 != i1) { // found an entry in the value map, so just return it. assert(i2->is_linked(), "should already be linked"); return i2; } ValueNumberingEffects vne(vmap()); i1->visit(&vne); } // i1 was not eliminated => append it assert(i1->next() == NULL, "shouldn't already be linked"); _last = _last->set_next(i1, canon.bci()); if (++_instruction_count >= InstructionCountCutoff && !bailed_out()) { // set the bailout state but complete normal processing. We // might do a little more work before noticing the bailout so we // want processing to continue normally until it's noticed. bailout("Method and/or inlining is too large"); } #ifndef PRODUCT if (PrintIRDuringConstruction) { InstructionPrinter ip; ip.print_line(i1); if (Verbose) { state()->print(); } } #endif // save state after modification of operand stack for StateSplit instructions StateSplit* s = i1->as_StateSplit(); if (s != NULL) { if (EliminateFieldAccess) { Intrinsic* intrinsic = s->as_Intrinsic(); if (s->as_Invoke() != NULL || (intrinsic && !intrinsic->preserves_state())) { _memory->kill(); } } s->set_state(state()->copy(ValueStack::StateAfter, canon.bci())); } // set up exception handlers for this instruction if necessary if (i1->can_trap()) { i1->set_exception_handlers(handle_exception(i1)); assert(i1->exception_state() != NULL || !i1->needs_exception_state() || bailed_out(), "handle_exception must set exception state"); } return i1; } Instruction* GraphBuilder::append(Instruction* instr) { assert(instr->as_StateSplit() == NULL || instr->as_BlockEnd() != NULL, "wrong append used"); return append_with_bci(instr, bci()); } Instruction* GraphBuilder::append_split(StateSplit* instr) { return append_with_bci(instr, bci()); } void GraphBuilder::null_check(Value value) { if (value->as_NewArray() != NULL || value->as_NewInstance() != NULL) { return; } else { Constant* con = value->as_Constant(); if (con) { ObjectType* c = con->type()->as_ObjectType(); if (c && c->is_loaded()) { ObjectConstant* oc = c->as_ObjectConstant(); if (!oc || !oc->value()->is_null_object()) { return; } } } } append(new NullCheck(value, copy_state_for_exception())); } XHandlers* GraphBuilder::handle_exception(Instruction* instruction) { if (!has_handler() && (!instruction->needs_exception_state() || instruction->exception_state() != NULL)) { assert(instruction->exception_state() == NULL || instruction->exception_state()->kind() == ValueStack::EmptyExceptionState || (instruction->exception_state()->kind() == ValueStack::ExceptionState && _compilation->env()->jvmti_can_access_local_variables()), "exception_state should be of exception kind"); return new XHandlers(); } XHandlers* exception_handlers = new XHandlers(); ScopeData* cur_scope_data = scope_data(); ValueStack* cur_state = instruction->state_before(); ValueStack* prev_state = NULL; int scope_count = 0; assert(cur_state != NULL, "state_before must be set"); do { int cur_bci = cur_state->bci(); assert(cur_scope_data->scope() == cur_state->scope(), "scopes do not match"); assert(cur_bci == SynchronizationEntryBCI || cur_bci == cur_scope_data->stream()->cur_bci(), "invalid bci"); // join with all potential exception handlers XHandlers* list = cur_scope_data->xhandlers(); const int n = list->length(); for (int i = 0; i < n; i++) { XHandler* h = list->handler_at(i); if (h->covers(cur_bci)) { // h is a potential exception handler => join it compilation()->set_has_exception_handlers(true); BlockBegin* entry = h->entry_block(); if (entry == block()) { // It's acceptable for an exception handler to cover itself // but we don't handle that in the parser currently. It's // very rare so we bailout instead of trying to handle it. BAILOUT_("exception handler covers itself", exception_handlers); } assert(entry->bci() == h->handler_bci(), "must match"); assert(entry->bci() == -1 || entry == cur_scope_data->block_at(entry->bci()), "blocks must correspond"); // previously this was a BAILOUT, but this is not necessary // now because asynchronous exceptions are not handled this way. assert(entry->state() == NULL || cur_state->total_locks_size() == entry->state()->total_locks_size(), "locks do not match"); // xhandler start with an empty expression stack if (cur_state->stack_size() != 0) { cur_state = cur_state->copy(ValueStack::ExceptionState, cur_state->bci()); } if (instruction->exception_state() == NULL) { instruction->set_exception_state(cur_state); } // Note: Usually this join must work. However, very // complicated jsr-ret structures where we don't ret from // the subroutine can cause the objects on the monitor // stacks to not match because blocks can be parsed twice. // The only test case we've seen so far which exhibits this // problem is caught by the infinite recursion test in // GraphBuilder::jsr() if the join doesn't work. if (!entry->try_merge(cur_state)) { BAILOUT_("error while joining with exception handler, prob. due to complicated jsr/rets", exception_handlers); } // add current state for correct handling of phi functions at begin of xhandler int phi_operand = entry->add_exception_state(cur_state); // add entry to the list of xhandlers of this block _block->add_exception_handler(entry); // add back-edge from xhandler entry to this block if (!entry->is_predecessor(_block)) { entry->add_predecessor(_block); } // clone XHandler because phi_operand and scope_count can not be shared XHandler* new_xhandler = new XHandler(h); new_xhandler->set_phi_operand(phi_operand); new_xhandler->set_scope_count(scope_count); exception_handlers->append(new_xhandler); // fill in exception handler subgraph lazily assert(!entry->is_set(BlockBegin::was_visited_flag), "entry must not be visited yet"); cur_scope_data->add_to_work_list(entry); // stop when reaching catchall if (h->catch_type() == 0) { return exception_handlers; } } } if (exception_handlers->length() == 0) { // This scope and all callees do not handle exceptions, so the local // variables of this scope are not needed. However, the scope itself is // required for a correct exception stack trace -> clear out the locals. if (_compilation->env()->jvmti_can_access_local_variables()) { cur_state = cur_state->copy(ValueStack::ExceptionState, cur_state->bci()); } else { cur_state = cur_state->copy(ValueStack::EmptyExceptionState, cur_state->bci()); } if (prev_state != NULL) { prev_state->set_caller_state(cur_state); } if (instruction->exception_state() == NULL) { instruction->set_exception_state(cur_state); } } // Set up iteration for next time. // If parsing a jsr, do not grab exception handlers from the // parent scopes for this method (already got them, and they // needed to be cloned) while (cur_scope_data->parsing_jsr()) { cur_scope_data = cur_scope_data->parent(); } assert(cur_scope_data->scope() == cur_state->scope(), "scopes do not match"); assert(cur_state->locks_size() == 0 || cur_state->locks_size() == 1, "unlocking must be done in a catchall exception handler"); prev_state = cur_state; cur_state = cur_state->caller_state(); cur_scope_data = cur_scope_data->parent(); scope_count++; } while (cur_scope_data != NULL); return exception_handlers; } // Helper class for simplifying Phis. class PhiSimplifier : public BlockClosure { private: bool _has_substitutions; Value simplify(Value v); public: PhiSimplifier(BlockBegin* start) : _has_substitutions(false) { start->iterate_preorder(this); if (_has_substitutions) { SubstitutionResolver sr(start); } } void block_do(BlockBegin* b); bool has_substitutions() const { return _has_substitutions; } }; Value PhiSimplifier::simplify(Value v) { Phi* phi = v->as_Phi(); if (phi == NULL) { // no phi function return v; } else if (v->has_subst()) { // already substituted; subst can be phi itself -> simplify return simplify(v->subst()); } else if (phi->is_set(Phi::cannot_simplify)) { // already tried to simplify phi before return phi; } else if (phi->is_set(Phi::visited)) { // break cycles in phi functions return phi; } else if (phi->type()->is_illegal()) { // illegal phi functions are ignored anyway return phi; } else { // mark phi function as processed to break cycles in phi functions phi->set(Phi::visited); // simplify x = [y, x] and x = [y, y] to y Value subst = NULL; int opd_count = phi->operand_count(); for (int i = 0; i < opd_count; i++) { Value opd = phi->operand_at(i); assert(opd != NULL, "Operand must exist!"); if (opd->type()->is_illegal()) { // if one operand is illegal, the entire phi function is illegal phi->make_illegal(); phi->clear(Phi::visited); return phi; } Value new_opd = simplify(opd); assert(new_opd != NULL, "Simplified operand must exist!"); if (new_opd != phi && new_opd != subst) { if (subst == NULL) { subst = new_opd; } else { // no simplification possible phi->set(Phi::cannot_simplify); phi->clear(Phi::visited); return phi; } } } // sucessfully simplified phi function assert(subst != NULL, "illegal phi function"); _has_substitutions = true; phi->clear(Phi::visited); phi->set_subst(subst); #ifndef PRODUCT if (PrintPhiFunctions) { tty->print_cr("simplified phi function %c%d to %c%d (Block B%d)", phi->type()->tchar(), phi->id(), subst->type()->tchar(), subst->id(), phi->block()->block_id()); } #endif return subst; } } void PhiSimplifier::block_do(BlockBegin* b) { for_each_phi_fun(b, phi, simplify(phi); ); #ifdef ASSERT for_each_phi_fun(b, phi, assert(phi->operand_count() != 1 || phi->subst() != phi, "missed trivial simplification"); ); ValueStack* state = b->state()->caller_state(); for_each_state_value(state, value, Phi* phi = value->as_Phi(); assert(phi == NULL || phi->block() != b, "must not have phi function to simplify in caller state"); ); #endif } // This method is called after all blocks are filled with HIR instructions // It eliminates all Phi functions of the form x = [y, y] and x = [y, x] void GraphBuilder::eliminate_redundant_phis(BlockBegin* start) { PhiSimplifier simplifier(start); } void GraphBuilder::connect_to_end(BlockBegin* beg) { // setup iteration kill_all(); _block = beg; _state = beg->state()->copy_for_parsing(); _last = beg; iterate_bytecodes_for_block(beg->bci()); } BlockEnd* GraphBuilder::iterate_bytecodes_for_block(int bci) { #ifndef PRODUCT if (PrintIRDuringConstruction) { tty->cr(); InstructionPrinter ip; ip.print_instr(_block); tty->cr(); ip.print_stack(_block->state()); tty->cr(); ip.print_inline_level(_block); ip.print_head(); tty->print_cr("locals size: %d stack size: %d", state()->locals_size(), state()->stack_size()); } #endif _skip_block = false; assert(state() != NULL, "ValueStack missing!"); CompileLog* log = compilation()->log(); ciBytecodeStream s(method()); s.reset_to_bci(bci); int prev_bci = bci; scope_data()->set_stream(&s); // iterate Bytecodes::Code code = Bytecodes::_illegal; bool push_exception = false; if (block()->is_set(BlockBegin::exception_entry_flag) && block()->next() == NULL) { // first thing in the exception entry block should be the exception object. push_exception = true; } while (!bailed_out() && last()->as_BlockEnd() == NULL && (code = stream()->next()) != ciBytecodeStream::EOBC() && (block_at(s.cur_bci()) == NULL || block_at(s.cur_bci()) == block())) { assert(state()->kind() == ValueStack::Parsing, "invalid state kind"); if (log != NULL) log->set_context("bc code='%d' bci='%d'", (int)code, s.cur_bci()); // Check for active jsr during OSR compilation if (compilation()->is_osr_compile() && scope()->is_top_scope() && parsing_jsr() && s.cur_bci() == compilation()->osr_bci()) { bailout("OSR not supported while a jsr is active"); } if (push_exception) { apush(append(new ExceptionObject())); push_exception = false; } // handle bytecode switch (code) { case Bytecodes::_nop : /* nothing to do */ break; case Bytecodes::_aconst_null : apush(append(new Constant(objectNull ))); break; case Bytecodes::_iconst_m1 : ipush(append(new Constant(new IntConstant (-1)))); break; case Bytecodes::_iconst_0 : ipush(append(new Constant(intZero ))); break; case Bytecodes::_iconst_1 : ipush(append(new Constant(intOne ))); break; case Bytecodes::_iconst_2 : ipush(append(new Constant(new IntConstant ( 2)))); break; case Bytecodes::_iconst_3 : ipush(append(new Constant(new IntConstant ( 3)))); break; case Bytecodes::_iconst_4 : ipush(append(new Constant(new IntConstant ( 4)))); break; case Bytecodes::_iconst_5 : ipush(append(new Constant(new IntConstant ( 5)))); break; case Bytecodes::_lconst_0 : lpush(append(new Constant(new LongConstant ( 0)))); break; case Bytecodes::_lconst_1 : lpush(append(new Constant(new LongConstant ( 1)))); break; case Bytecodes::_fconst_0 : fpush(append(new Constant(new FloatConstant ( 0)))); break; case Bytecodes::_fconst_1 : fpush(append(new Constant(new FloatConstant ( 1)))); break; case Bytecodes::_fconst_2 : fpush(append(new Constant(new FloatConstant ( 2)))); break; case Bytecodes::_dconst_0 : dpush(append(new Constant(new DoubleConstant( 0)))); break; case Bytecodes::_dconst_1 : dpush(append(new Constant(new DoubleConstant( 1)))); break; case Bytecodes::_bipush : ipush(append(new Constant(new IntConstant(((signed char*)s.cur_bcp())[1])))); break; case Bytecodes::_sipush : ipush(append(new Constant(new IntConstant((short)Bytes::get_Java_u2(s.cur_bcp()+1))))); break; case Bytecodes::_ldc : // fall through case Bytecodes::_ldc_w : // fall through case Bytecodes::_ldc2_w : load_constant(); break; case Bytecodes::_iload : load_local(intType , s.get_index()); break; case Bytecodes::_lload : load_local(longType , s.get_index()); break; case Bytecodes::_fload : load_local(floatType , s.get_index()); break; case Bytecodes::_dload : load_local(doubleType , s.get_index()); break; case Bytecodes::_aload : load_local(instanceType, s.get_index()); break; case Bytecodes::_iload_0 : load_local(intType , 0); break; case Bytecodes::_iload_1 : load_local(intType , 1); break; case Bytecodes::_iload_2 : load_local(intType , 2); break; case Bytecodes::_iload_3 : load_local(intType , 3); break; case Bytecodes::_lload_0 : load_local(longType , 0); break; case Bytecodes::_lload_1 : load_local(longType , 1); break; case Bytecodes::_lload_2 : load_local(longType , 2); break; case Bytecodes::_lload_3 : load_local(longType , 3); break; case Bytecodes::_fload_0 : load_local(floatType , 0); break; case Bytecodes::_fload_1 : load_local(floatType , 1); break; case Bytecodes::_fload_2 : load_local(floatType , 2); break; case Bytecodes::_fload_3 : load_local(floatType , 3); break; case Bytecodes::_dload_0 : load_local(doubleType, 0); break; case Bytecodes::_dload_1 : load_local(doubleType, 1); break; case Bytecodes::_dload_2 : load_local(doubleType, 2); break; case Bytecodes::_dload_3 : load_local(doubleType, 3); break; case Bytecodes::_aload_0 : load_local(objectType, 0); break; case Bytecodes::_aload_1 : load_local(objectType, 1); break; case Bytecodes::_aload_2 : load_local(objectType, 2); break; case Bytecodes::_aload_3 : load_local(objectType, 3); break; case Bytecodes::_iaload : load_indexed(T_INT ); break; case Bytecodes::_laload : load_indexed(T_LONG ); break; case Bytecodes::_faload : load_indexed(T_FLOAT ); break; case Bytecodes::_daload : load_indexed(T_DOUBLE); break; case Bytecodes::_aaload : load_indexed(T_OBJECT); break; case Bytecodes::_baload : load_indexed(T_BYTE ); break; case Bytecodes::_caload : load_indexed(T_CHAR ); break; case Bytecodes::_saload : load_indexed(T_SHORT ); break; case Bytecodes::_istore : store_local(intType , s.get_index()); break; case Bytecodes::_lstore : store_local(longType , s.get_index()); break; case Bytecodes::_fstore : store_local(floatType , s.get_index()); break; case Bytecodes::_dstore : store_local(doubleType, s.get_index()); break; case Bytecodes::_astore : store_local(objectType, s.get_index()); break; case Bytecodes::_istore_0 : store_local(intType , 0); break; case Bytecodes::_istore_1 : store_local(intType , 1); break; case Bytecodes::_istore_2 : store_local(intType , 2); break; case Bytecodes::_istore_3 : store_local(intType , 3); break; case Bytecodes::_lstore_0 : store_local(longType , 0); break; case Bytecodes::_lstore_1 : store_local(longType , 1); break; case Bytecodes::_lstore_2 : store_local(longType , 2); break; case Bytecodes::_lstore_3 : store_local(longType , 3); break; case Bytecodes::_fstore_0 : store_local(floatType , 0); break; case Bytecodes::_fstore_1 : store_local(floatType , 1); break; case Bytecodes::_fstore_2 : store_local(floatType , 2); break; case Bytecodes::_fstore_3 : store_local(floatType , 3); break; case Bytecodes::_dstore_0 : store_local(doubleType, 0); break; case Bytecodes::_dstore_1 : store_local(doubleType, 1); break; case Bytecodes::_dstore_2 : store_local(doubleType, 2); break; case Bytecodes::_dstore_3 : store_local(doubleType, 3); break; case Bytecodes::_astore_0 : store_local(objectType, 0); break; case Bytecodes::_astore_1 : store_local(objectType, 1); break; case Bytecodes::_astore_2 : store_local(objectType, 2); break; case Bytecodes::_astore_3 : store_local(objectType, 3); break; case Bytecodes::_iastore : store_indexed(T_INT ); break; case Bytecodes::_lastore : store_indexed(T_LONG ); break; case Bytecodes::_fastore : store_indexed(T_FLOAT ); break; case Bytecodes::_dastore : store_indexed(T_DOUBLE); break; case Bytecodes::_aastore : store_indexed(T_OBJECT); break; case Bytecodes::_bastore : store_indexed(T_BYTE ); break; case Bytecodes::_castore : store_indexed(T_CHAR ); break; case Bytecodes::_sastore : store_indexed(T_SHORT ); break; case Bytecodes::_pop : // fall through case Bytecodes::_pop2 : // fall through case Bytecodes::_dup : // fall through case Bytecodes::_dup_x1 : // fall through case Bytecodes::_dup_x2 : // fall through case Bytecodes::_dup2 : // fall through case Bytecodes::_dup2_x1 : // fall through case Bytecodes::_dup2_x2 : // fall through case Bytecodes::_swap : stack_op(code); break; case Bytecodes::_iadd : arithmetic_op(intType , code); break; case Bytecodes::_ladd : arithmetic_op(longType , code); break; case Bytecodes::_fadd : arithmetic_op(floatType , code); break; case Bytecodes::_dadd : arithmetic_op(doubleType, code); break; case Bytecodes::_isub : arithmetic_op(intType , code); break; case Bytecodes::_lsub : arithmetic_op(longType , code); break; case Bytecodes::_fsub : arithmetic_op(floatType , code); break; case Bytecodes::_dsub : arithmetic_op(doubleType, code); break; case Bytecodes::_imul : arithmetic_op(intType , code); break; case Bytecodes::_lmul : arithmetic_op(longType , code); break; case Bytecodes::_fmul : arithmetic_op(floatType , code); break; case Bytecodes::_dmul : arithmetic_op(doubleType, code); break; case Bytecodes::_idiv : arithmetic_op(intType , code, copy_state_for_exception()); break; case Bytecodes::_ldiv : arithmetic_op(longType , code, copy_state_for_exception()); break; case Bytecodes::_fdiv : arithmetic_op(floatType , code); break; case Bytecodes::_ddiv : arithmetic_op(doubleType, code); break; case Bytecodes::_irem : arithmetic_op(intType , code, copy_state_for_exception()); break; case Bytecodes::_lrem : arithmetic_op(longType , code, copy_state_for_exception()); break; case Bytecodes::_frem : arithmetic_op(floatType , code); break; case Bytecodes::_drem : arithmetic_op(doubleType, code); break; case Bytecodes::_ineg : negate_op(intType ); break; case Bytecodes::_lneg : negate_op(longType ); break; case Bytecodes::_fneg : negate_op(floatType ); break; case Bytecodes::_dneg : negate_op(doubleType); break; case Bytecodes::_ishl : shift_op(intType , code); break; case Bytecodes::_lshl : shift_op(longType, code); break; case Bytecodes::_ishr : shift_op(intType , code); break; case Bytecodes::_lshr : shift_op(longType, code); break; case Bytecodes::_iushr : shift_op(intType , code); break; case Bytecodes::_lushr : shift_op(longType, code); break; case Bytecodes::_iand : logic_op(intType , code); break; case Bytecodes::_land : logic_op(longType, code); break; case Bytecodes::_ior : logic_op(intType , code); break; case Bytecodes::_lor : logic_op(longType, code); break; case Bytecodes::_ixor : logic_op(intType , code); break; case Bytecodes::_lxor : logic_op(longType, code); break; case Bytecodes::_iinc : increment(); break; case Bytecodes::_i2l : convert(code, T_INT , T_LONG ); break; case Bytecodes::_i2f : convert(code, T_INT , T_FLOAT ); break; case Bytecodes::_i2d : convert(code, T_INT , T_DOUBLE); break; case Bytecodes::_l2i : convert(code, T_LONG , T_INT ); break; case Bytecodes::_l2f : convert(code, T_LONG , T_FLOAT ); break; case Bytecodes::_l2d : convert(code, T_LONG , T_DOUBLE); break; case Bytecodes::_f2i : convert(code, T_FLOAT , T_INT ); break; case Bytecodes::_f2l : convert(code, T_FLOAT , T_LONG ); break; case Bytecodes::_f2d : convert(code, T_FLOAT , T_DOUBLE); break; case Bytecodes::_d2i : convert(code, T_DOUBLE, T_INT ); break; case Bytecodes::_d2l : convert(code, T_DOUBLE, T_LONG ); break; case Bytecodes::_d2f : convert(code, T_DOUBLE, T_FLOAT ); break; case Bytecodes::_i2b : convert(code, T_INT , T_BYTE ); break; case Bytecodes::_i2c : convert(code, T_INT , T_CHAR ); break; case Bytecodes::_i2s : convert(code, T_INT , T_SHORT ); break; case Bytecodes::_lcmp : compare_op(longType , code); break; case Bytecodes::_fcmpl : compare_op(floatType , code); break; case Bytecodes::_fcmpg : compare_op(floatType , code); break; case Bytecodes::_dcmpl : compare_op(doubleType, code); break; case Bytecodes::_dcmpg : compare_op(doubleType, code); break; case Bytecodes::_ifeq : if_zero(intType , If::eql); break; case Bytecodes::_ifne : if_zero(intType , If::neq); break; case Bytecodes::_iflt : if_zero(intType , If::lss); break; case Bytecodes::_ifge : if_zero(intType , If::geq); break; case Bytecodes::_ifgt : if_zero(intType , If::gtr); break; case Bytecodes::_ifle : if_zero(intType , If::leq); break; case Bytecodes::_if_icmpeq : if_same(intType , If::eql); break; case Bytecodes::_if_icmpne : if_same(intType , If::neq); break; case Bytecodes::_if_icmplt : if_same(intType , If::lss); break; case Bytecodes::_if_icmpge : if_same(intType , If::geq); break; case Bytecodes::_if_icmpgt : if_same(intType , If::gtr); break; case Bytecodes::_if_icmple : if_same(intType , If::leq); break; case Bytecodes::_if_acmpeq : if_same(objectType, If::eql); break; case Bytecodes::_if_acmpne : if_same(objectType, If::neq); break; case Bytecodes::_goto : _goto(s.cur_bci(), s.get_dest()); break; case Bytecodes::_jsr : jsr(s.get_dest()); break; case Bytecodes::_ret : ret(s.get_index()); break; case Bytecodes::_tableswitch : table_switch(); break; case Bytecodes::_lookupswitch : lookup_switch(); break; case Bytecodes::_ireturn : method_return(ipop()); break; case Bytecodes::_lreturn : method_return(lpop()); break; case Bytecodes::_freturn : method_return(fpop()); break; case Bytecodes::_dreturn : method_return(dpop()); break; case Bytecodes::_areturn : method_return(apop()); break; case Bytecodes::_return : method_return(NULL ); break; case Bytecodes::_getstatic : // fall through case Bytecodes::_putstatic : // fall through case Bytecodes::_getfield : // fall through case Bytecodes::_putfield : access_field(code); break; case Bytecodes::_invokevirtual : // fall through case Bytecodes::_invokespecial : // fall through case Bytecodes::_invokestatic : // fall through case Bytecodes::_invokedynamic : // fall through case Bytecodes::_invokeinterface: invoke(code); break; case Bytecodes::_new : new_instance(s.get_index_u2()); break; case Bytecodes::_newarray : new_type_array(); break; case Bytecodes::_anewarray : new_object_array(); break; case Bytecodes::_arraylength : { ValueStack* state_before = copy_state_for_exception(); ipush(append(new ArrayLength(apop(), state_before))); break; } case Bytecodes::_athrow : throw_op(s.cur_bci()); break; case Bytecodes::_checkcast : check_cast(s.get_index_u2()); break; case Bytecodes::_instanceof : instance_of(s.get_index_u2()); break; case Bytecodes::_monitorenter : monitorenter(apop(), s.cur_bci()); break; case Bytecodes::_monitorexit : monitorexit (apop(), s.cur_bci()); break; case Bytecodes::_wide : ShouldNotReachHere(); break; case Bytecodes::_multianewarray : new_multi_array(s.cur_bcp()[3]); break; case Bytecodes::_ifnull : if_null(objectType, If::eql); break; case Bytecodes::_ifnonnull : if_null(objectType, If::neq); break; case Bytecodes::_goto_w : _goto(s.cur_bci(), s.get_far_dest()); break; case Bytecodes::_jsr_w : jsr(s.get_far_dest()); break; case Bytecodes::_breakpoint : BAILOUT_("concurrent setting of breakpoint", NULL); default : ShouldNotReachHere(); break; } if (log != NULL) log->clear_context(); // skip marker if nothing was printed // save current bci to setup Goto at the end prev_bci = s.cur_bci(); } CHECK_BAILOUT_(NULL); // stop processing of this block (see try_inline_full) if (_skip_block) { _skip_block = false; assert(_last && _last->as_BlockEnd(), ""); return _last->as_BlockEnd(); } // if there are any, check if last instruction is a BlockEnd instruction BlockEnd* end = last()->as_BlockEnd(); if (end == NULL) { // all blocks must end with a BlockEnd instruction => add a Goto end = new Goto(block_at(s.cur_bci()), false); append(end); } assert(end == last()->as_BlockEnd(), "inconsistency"); assert(end->state() != NULL, "state must already be present"); assert(end->as_Return() == NULL || end->as_Throw() == NULL || end->state()->stack_size() == 0, "stack not needed for return and throw"); // connect to begin & set state // NOTE that inlining may have changed the block we are parsing block()->set_end(end); // propagate state for (int i = end->number_of_sux() - 1; i >= 0; i--) { BlockBegin* sux = end->sux_at(i); assert(sux->is_predecessor(block()), "predecessor missing"); // be careful, bailout if bytecodes are strange if (!sux->try_merge(end->state())) BAILOUT_("block join failed", NULL); scope_data()->add_to_work_list(end->sux_at(i)); } scope_data()->set_stream(NULL); // done return end; } void GraphBuilder::iterate_all_blocks(bool start_in_current_block_for_inlining) { do { if (start_in_current_block_for_inlining && !bailed_out()) { iterate_bytecodes_for_block(0); start_in_current_block_for_inlining = false; } else { BlockBegin* b; while ((b = scope_data()->remove_from_work_list()) != NULL) { if (!b->is_set(BlockBegin::was_visited_flag)) { if (b->is_set(BlockBegin::osr_entry_flag)) { // we're about to parse the osr entry block, so make sure // we setup the OSR edge leading into this block so that // Phis get setup correctly. setup_osr_entry_block(); // this is no longer the osr entry block, so clear it. b->clear(BlockBegin::osr_entry_flag); } b->set(BlockBegin::was_visited_flag); connect_to_end(b); } } } } while (!bailed_out() && !scope_data()->is_work_list_empty()); } bool GraphBuilder::_can_trap [Bytecodes::number_of_java_codes]; void GraphBuilder::initialize() { // the following bytecodes are assumed to potentially // throw exceptions in compiled code - note that e.g. // monitorexit & the return bytecodes do not throw // exceptions since monitor pairing proved that they // succeed (if monitor pairing succeeded) Bytecodes::Code can_trap_list[] = { Bytecodes::_ldc , Bytecodes::_ldc_w , Bytecodes::_ldc2_w , Bytecodes::_iaload , Bytecodes::_laload , Bytecodes::_faload , Bytecodes::_daload , Bytecodes::_aaload , Bytecodes::_baload , Bytecodes::_caload , Bytecodes::_saload , Bytecodes::_iastore , Bytecodes::_lastore , Bytecodes::_fastore , Bytecodes::_dastore , Bytecodes::_aastore , Bytecodes::_bastore , Bytecodes::_castore , Bytecodes::_sastore , Bytecodes::_idiv , Bytecodes::_ldiv , Bytecodes::_irem , Bytecodes::_lrem , Bytecodes::_getstatic , Bytecodes::_putstatic , Bytecodes::_getfield , Bytecodes::_putfield , Bytecodes::_invokevirtual , Bytecodes::_invokespecial , Bytecodes::_invokestatic , Bytecodes::_invokedynamic , Bytecodes::_invokeinterface , Bytecodes::_new , Bytecodes::_newarray , Bytecodes::_anewarray , Bytecodes::_arraylength , Bytecodes::_athrow , Bytecodes::_checkcast , Bytecodes::_instanceof , Bytecodes::_monitorenter , Bytecodes::_multianewarray }; // inititialize trap tables for (int i = 0; i < Bytecodes::number_of_java_codes; i++) { _can_trap[i] = false; } // set standard trap info for (uint j = 0; j < ARRAY_SIZE(can_trap_list); j++) { _can_trap[can_trap_list[j]] = true; } } BlockBegin* GraphBuilder::header_block(BlockBegin* entry, BlockBegin::Flag f, ValueStack* state) { assert(entry->is_set(f), "entry/flag mismatch"); // create header block BlockBegin* h = new BlockBegin(entry->bci()); h->set_depth_first_number(0); Value l = h; BlockEnd* g = new Goto(entry, false); l->set_next(g, entry->bci()); h->set_end(g); h->set(f); // setup header block end state ValueStack* s = state->copy(ValueStack::StateAfter, entry->bci()); // can use copy since stack is empty (=> no phis) assert(s->stack_is_empty(), "must have empty stack at entry point"); g->set_state(s); return h; } BlockBegin* GraphBuilder::setup_start_block(int osr_bci, BlockBegin* std_entry, BlockBegin* osr_entry, ValueStack* state) { BlockBegin* start = new BlockBegin(0); // This code eliminates the empty start block at the beginning of // each method. Previously, each method started with the // start-block created below, and this block was followed by the // header block that was always empty. This header block is only // necesary if std_entry is also a backward branch target because // then phi functions may be necessary in the header block. It's // also necessary when profiling so that there's a single block that // can increment the interpreter_invocation_count. BlockBegin* new_header_block; if (std_entry->number_of_preds() > 0 || count_invocations() || count_backedges()) { new_header_block = header_block(std_entry, BlockBegin::std_entry_flag, state); } else { new_header_block = std_entry; } // setup start block (root for the IR graph) Base* base = new Base( new_header_block, osr_entry ); start->set_next(base, 0); start->set_end(base); // create & setup state for start block start->set_state(state->copy(ValueStack::StateAfter, std_entry->bci())); base->set_state(state->copy(ValueStack::StateAfter, std_entry->bci())); if (base->std_entry()->state() == NULL) { // setup states for header blocks base->std_entry()->merge(state); } assert(base->std_entry()->state() != NULL, ""); return start; } void GraphBuilder::setup_osr_entry_block() { assert(compilation()->is_osr_compile(), "only for osrs"); int osr_bci = compilation()->osr_bci(); ciBytecodeStream s(method()); s.reset_to_bci(osr_bci); s.next(); scope_data()->set_stream(&s); // create a new block to be the osr setup code _osr_entry = new BlockBegin(osr_bci); _osr_entry->set(BlockBegin::osr_entry_flag); _osr_entry->set_depth_first_number(0); BlockBegin* target = bci2block()->at(osr_bci); assert(target != NULL && target->is_set(BlockBegin::osr_entry_flag), "must be there"); // the osr entry has no values for locals ValueStack* state = target->state()->copy(); _osr_entry->set_state(state); kill_all(); _block = _osr_entry; _state = _osr_entry->state()->copy(); assert(_state->bci() == osr_bci, "mismatch"); _last = _osr_entry; Value e = append(new OsrEntry()); e->set_needs_null_check(false); // OSR buffer is // // locals[nlocals-1..0] // monitors[number_of_locks-1..0] // // locals is a direct copy of the interpreter frame so in the osr buffer // so first slot in the local array is the last local from the interpreter // and last slot is local[0] (receiver) from the interpreter // // Similarly with locks. The first lock slot in the osr buffer is the nth lock // from the interpreter frame, the nth lock slot in the osr buffer is 0th lock // in the interpreter frame (the method lock if a sync method) // Initialize monitors in the compiled activation. int index; Value local; // find all the locals that the interpreter thinks contain live oops const BitMap live_oops = method()->live_local_oops_at_bci(osr_bci); // compute the offset into the locals so that we can treat the buffer // as if the locals were still in the interpreter frame int locals_offset = BytesPerWord * (method()->max_locals() - 1); for_each_local_value(state, index, local) { int offset = locals_offset - (index + local->type()->size() - 1) * BytesPerWord; Value get; if (local->type()->is_object_kind() && !live_oops.at(index)) { // The interpreter thinks this local is dead but the compiler // doesn't so pretend that the interpreter passed in null. get = append(new Constant(objectNull)); } else { get = append(new UnsafeGetRaw(as_BasicType(local->type()), e, append(new Constant(new IntConstant(offset))), 0, true /*unaligned*/, true /*wide*/)); } _state->store_local(index, get); } // the storage for the OSR buffer is freed manually in the LIRGenerator. assert(state->caller_state() == NULL, "should be top scope"); state->clear_locals(); Goto* g = new Goto(target, false); append(g); _osr_entry->set_end(g); target->merge(_osr_entry->end()->state()); scope_data()->set_stream(NULL); } ValueStack* GraphBuilder::state_at_entry() { ValueStack* state = new ValueStack(scope(), NULL); // Set up locals for receiver int idx = 0; if (!method()->is_static()) { // we should always see the receiver state->store_local(idx, new Local(method()->holder(), objectType, idx)); idx = 1; } // Set up locals for incoming arguments ciSignature* sig = method()->signature(); for (int i = 0; i < sig->count(); i++) { ciType* type = sig->type_at(i); BasicType basic_type = type->basic_type(); // don't allow T_ARRAY to propagate into locals types if (basic_type == T_ARRAY) basic_type = T_OBJECT; ValueType* vt = as_ValueType(basic_type); state->store_local(idx, new Local(type, vt, idx)); idx += type->size(); } // lock synchronized method if (method()->is_synchronized()) { state->lock(NULL); } return state; } GraphBuilder::GraphBuilder(Compilation* compilation, IRScope* scope) : _scope_data(NULL) , _instruction_count(0) , _osr_entry(NULL) , _memory(new MemoryBuffer()) , _compilation(compilation) , _inline_bailout_msg(NULL) { int osr_bci = compilation->osr_bci(); // determine entry points and bci2block mapping BlockListBuilder blm(compilation, scope, osr_bci); CHECK_BAILOUT(); BlockList* bci2block = blm.bci2block(); BlockBegin* start_block = bci2block->at(0); push_root_scope(scope, bci2block, start_block); // setup state for std entry _initial_state = state_at_entry(); start_block->merge(_initial_state); // complete graph _vmap = new ValueMap(); switch (scope->method()->intrinsic_id()) { case vmIntrinsics::_dabs : // fall through case vmIntrinsics::_dsqrt : // fall through case vmIntrinsics::_dsin : // fall through case vmIntrinsics::_dcos : // fall through case vmIntrinsics::_dtan : // fall through case vmIntrinsics::_dlog : // fall through case vmIntrinsics::_dlog10 : // fall through case vmIntrinsics::_dexp : // fall through case vmIntrinsics::_dpow : // fall through { // Compiles where the root method is an intrinsic need a special // compilation environment because the bytecodes for the method // shouldn't be parsed during the compilation, only the special // Intrinsic node should be emitted. If this isn't done the the // code for the inlined version will be different than the root // compiled version which could lead to monotonicity problems on // intel. // Set up a stream so that appending instructions works properly. ciBytecodeStream s(scope->method()); s.reset_to_bci(0); scope_data()->set_stream(&s); s.next(); // setup the initial block state _block = start_block; _state = start_block->state()->copy_for_parsing(); _last = start_block; load_local(doubleType, 0); if (scope->method()->intrinsic_id() == vmIntrinsics::_dpow) { load_local(doubleType, 2); } // Emit the intrinsic node. bool result = try_inline_intrinsics(scope->method()); if (!result) BAILOUT("failed to inline intrinsic"); method_return(dpop()); // connect the begin and end blocks and we're all done. BlockEnd* end = last()->as_BlockEnd(); block()->set_end(end); break; } case vmIntrinsics::_Reference_get: { { // With java.lang.ref.reference.get() we must go through the // intrinsic - when G1 is enabled - even when get() is the root // method of the compile so that, if necessary, the value in // the referent field of the reference object gets recorded by // the pre-barrier code. // Specifically, if G1 is enabled, the value in the referent // field is recorded by the G1 SATB pre barrier. This will // result in the referent being marked live and the reference // object removed from the list of discovered references during // reference processing. // Also we need intrinsic to prevent commoning reads from this field // across safepoint since GC can change its value. // Set up a stream so that appending instructions works properly. ciBytecodeStream s(scope->method()); s.reset_to_bci(0); scope_data()->set_stream(&s); s.next(); // setup the initial block state _block = start_block; _state = start_block->state()->copy_for_parsing(); _last = start_block; load_local(objectType, 0); // Emit the intrinsic node. bool result = try_inline_intrinsics(scope->method()); if (!result) BAILOUT("failed to inline intrinsic"); method_return(apop()); // connect the begin and end blocks and we're all done. BlockEnd* end = last()->as_BlockEnd(); block()->set_end(end); break; } // Otherwise, fall thru } default: scope_data()->add_to_work_list(start_block); iterate_all_blocks(); break; } CHECK_BAILOUT(); _start = setup_start_block(osr_bci, start_block, _osr_entry, _initial_state); eliminate_redundant_phis(_start); NOT_PRODUCT(if (PrintValueNumbering && Verbose) print_stats()); // for osr compile, bailout if some requirements are not fulfilled if (osr_bci != -1) { BlockBegin* osr_block = blm.bci2block()->at(osr_bci); assert(osr_block->is_set(BlockBegin::was_visited_flag),"osr entry must have been visited for osr compile"); // check if osr entry point has empty stack - we cannot handle non-empty stacks at osr entry points if (!osr_block->state()->stack_is_empty()) { BAILOUT("stack not empty at OSR entry point"); } } #ifndef PRODUCT if (PrintCompilation && Verbose) tty->print_cr("Created %d Instructions", _instruction_count); #endif } ValueStack* GraphBuilder::copy_state_before() { return copy_state_before_with_bci(bci()); } ValueStack* GraphBuilder::copy_state_exhandling() { return copy_state_exhandling_with_bci(bci()); } ValueStack* GraphBuilder::copy_state_for_exception() { return copy_state_for_exception_with_bci(bci()); } ValueStack* GraphBuilder::copy_state_before_with_bci(int bci) { return state()->copy(ValueStack::StateBefore, bci); } ValueStack* GraphBuilder::copy_state_exhandling_with_bci(int bci) { if (!has_handler()) return NULL; return state()->copy(ValueStack::StateBefore, bci); } ValueStack* GraphBuilder::copy_state_for_exception_with_bci(int bci) { ValueStack* s = copy_state_exhandling_with_bci(bci); if (s == NULL) { if (_compilation->env()->jvmti_can_access_local_variables()) { s = state()->copy(ValueStack::ExceptionState, bci); } else { s = state()->copy(ValueStack::EmptyExceptionState, bci); } } return s; } int GraphBuilder::recursive_inline_level(ciMethod* cur_callee) const { int recur_level = 0; for (IRScope* s = scope(); s != NULL; s = s->caller()) { if (s->method() == cur_callee) { ++recur_level; } } return recur_level; } bool GraphBuilder::try_inline(ciMethod* callee, bool holder_known, Bytecodes::Code bc, Value receiver) { const char* msg = NULL; // clear out any existing inline bailout condition clear_inline_bailout(); // exclude methods we don't want to inline msg = should_not_inline(callee); if (msg != NULL) { print_inlining(callee, msg, /*success*/ false); return false; } // method handle invokes if (callee->is_method_handle_intrinsic()) { return try_method_handle_inline(callee); } // handle intrinsics if (callee->intrinsic_id() != vmIntrinsics::_none) { if (try_inline_intrinsics(callee)) { print_inlining(callee, "intrinsic"); return true; } // try normal inlining } // certain methods cannot be parsed at all msg = check_can_parse(callee); if (msg != NULL) { print_inlining(callee, msg, /*success*/ false); return false; } // If bytecode not set use the current one. if (bc == Bytecodes::_illegal) { bc = code(); } if (try_inline_full(callee, holder_known, bc, receiver)) return true; // Entire compilation could fail during try_inline_full call. // In that case printing inlining decision info is useless. if (!bailed_out()) print_inlining(callee, _inline_bailout_msg, /*success*/ false); return false; } const char* GraphBuilder::check_can_parse(ciMethod* callee) const { // Certain methods cannot be parsed at all: if ( callee->is_native()) return "native method"; if ( callee->is_abstract()) return "abstract method"; if (!callee->can_be_compiled()) return "not compilable (disabled)"; return NULL; } // negative filter: should callee NOT be inlined? returns NULL, ok to inline, or rejection msg const char* GraphBuilder::should_not_inline(ciMethod* callee) const { if ( callee->should_exclude()) return "excluded by CompilerOracle"; if ( callee->should_not_inline()) return "disallowed by CompilerOracle"; if ( callee->dont_inline()) return "don't inline by annotation"; return NULL; } bool GraphBuilder::try_inline_intrinsics(ciMethod* callee) { if (callee->is_synchronized()) { // We don't currently support any synchronized intrinsics return false; } // callee seems like a good candidate // determine id vmIntrinsics::ID id = callee->intrinsic_id(); if (!InlineNatives && id != vmIntrinsics::_Reference_get) { // InlineNatives does not control Reference.get INLINE_BAILOUT("intrinsic method inlining disabled"); } bool preserves_state = false; bool cantrap = true; switch (id) { case vmIntrinsics::_arraycopy: if (!InlineArrayCopy) return false; break; #ifdef TRACE_HAVE_INTRINSICS case vmIntrinsics::_classID: case vmIntrinsics::_threadID: preserves_state = true; cantrap = true; break; case vmIntrinsics::_counterTime: preserves_state = true; cantrap = false; break; #endif case vmIntrinsics::_currentTimeMillis: case vmIntrinsics::_nanoTime: preserves_state = true; cantrap = false; break; case vmIntrinsics::_floatToRawIntBits : case vmIntrinsics::_intBitsToFloat : case vmIntrinsics::_doubleToRawLongBits : case vmIntrinsics::_longBitsToDouble : if (!InlineMathNatives) return false; preserves_state = true; cantrap = false; break; case vmIntrinsics::_getClass : case vmIntrinsics::_isInstance : if (!InlineClassNatives) return false; preserves_state = true; break; case vmIntrinsics::_currentThread : if (!InlineThreadNatives) return false; preserves_state = true; cantrap = false; break; case vmIntrinsics::_dabs : // fall through case vmIntrinsics::_dsqrt : // fall through case vmIntrinsics::_dsin : // fall through case vmIntrinsics::_dcos : // fall through case vmIntrinsics::_dtan : // fall through case vmIntrinsics::_dlog : // fall through case vmIntrinsics::_dlog10 : // fall through case vmIntrinsics::_dexp : // fall through case vmIntrinsics::_dpow : // fall through if (!InlineMathNatives) return false; cantrap = false; preserves_state = true; break; // Use special nodes for Unsafe instructions so we can more easily // perform an address-mode optimization on the raw variants case vmIntrinsics::_getObject : return append_unsafe_get_obj(callee, T_OBJECT, false); case vmIntrinsics::_getBoolean: return append_unsafe_get_obj(callee, T_BOOLEAN, false); case vmIntrinsics::_getByte : return append_unsafe_get_obj(callee, T_BYTE, false); case vmIntrinsics::_getShort : return append_unsafe_get_obj(callee, T_SHORT, false); case vmIntrinsics::_getChar : return append_unsafe_get_obj(callee, T_CHAR, false); case vmIntrinsics::_getInt : return append_unsafe_get_obj(callee, T_INT, false); case vmIntrinsics::_getLong : return append_unsafe_get_obj(callee, T_LONG, false); case vmIntrinsics::_getFloat : return append_unsafe_get_obj(callee, T_FLOAT, false); case vmIntrinsics::_getDouble : return append_unsafe_get_obj(callee, T_DOUBLE, false); case vmIntrinsics::_putObject : return append_unsafe_put_obj(callee, T_OBJECT, false); case vmIntrinsics::_putBoolean: return append_unsafe_put_obj(callee, T_BOOLEAN, false); case vmIntrinsics::_putByte : return append_unsafe_put_obj(callee, T_BYTE, false); case vmIntrinsics::_putShort : return append_unsafe_put_obj(callee, T_SHORT, false); case vmIntrinsics::_putChar : return append_unsafe_put_obj(callee, T_CHAR, false); case vmIntrinsics::_putInt : return append_unsafe_put_obj(callee, T_INT, false); case vmIntrinsics::_putLong : return append_unsafe_put_obj(callee, T_LONG, false); case vmIntrinsics::_putFloat : return append_unsafe_put_obj(callee, T_FLOAT, false); case vmIntrinsics::_putDouble : return append_unsafe_put_obj(callee, T_DOUBLE, false); case vmIntrinsics::_getObjectVolatile : return append_unsafe_get_obj(callee, T_OBJECT, true); case vmIntrinsics::_getBooleanVolatile: return append_unsafe_get_obj(callee, T_BOOLEAN, true); case vmIntrinsics::_getByteVolatile : return append_unsafe_get_obj(callee, T_BYTE, true); case vmIntrinsics::_getShortVolatile : return append_unsafe_get_obj(callee, T_SHORT, true); case vmIntrinsics::_getCharVolatile : return append_unsafe_get_obj(callee, T_CHAR, true); case vmIntrinsics::_getIntVolatile : return append_unsafe_get_obj(callee, T_INT, true); case vmIntrinsics::_getLongVolatile : return append_unsafe_get_obj(callee, T_LONG, true); case vmIntrinsics::_getFloatVolatile : return append_unsafe_get_obj(callee, T_FLOAT, true); case vmIntrinsics::_getDoubleVolatile : return append_unsafe_get_obj(callee, T_DOUBLE, true); case vmIntrinsics::_putObjectVolatile : return append_unsafe_put_obj(callee, T_OBJECT, true); case vmIntrinsics::_putBooleanVolatile: return append_unsafe_put_obj(callee, T_BOOLEAN, true); case vmIntrinsics::_putByteVolatile : return append_unsafe_put_obj(callee, T_BYTE, true); case vmIntrinsics::_putShortVolatile : return append_unsafe_put_obj(callee, T_SHORT, true); case vmIntrinsics::_putCharVolatile : return append_unsafe_put_obj(callee, T_CHAR, true); case vmIntrinsics::_putIntVolatile : return append_unsafe_put_obj(callee, T_INT, true); case vmIntrinsics::_putLongVolatile : return append_unsafe_put_obj(callee, T_LONG, true); case vmIntrinsics::_putFloatVolatile : return append_unsafe_put_obj(callee, T_FLOAT, true); case vmIntrinsics::_putDoubleVolatile : return append_unsafe_put_obj(callee, T_DOUBLE, true); case vmIntrinsics::_getByte_raw : return append_unsafe_get_raw(callee, T_BYTE); case vmIntrinsics::_getShort_raw : return append_unsafe_get_raw(callee, T_SHORT); case vmIntrinsics::_getChar_raw : return append_unsafe_get_raw(callee, T_CHAR); case vmIntrinsics::_getInt_raw : return append_unsafe_get_raw(callee, T_INT); case vmIntrinsics::_getLong_raw : return append_unsafe_get_raw(callee, T_LONG); case vmIntrinsics::_getFloat_raw : return append_unsafe_get_raw(callee, T_FLOAT); case vmIntrinsics::_getDouble_raw : return append_unsafe_get_raw(callee, T_DOUBLE); case vmIntrinsics::_putByte_raw : return append_unsafe_put_raw(callee, T_BYTE); case vmIntrinsics::_putShort_raw : return append_unsafe_put_raw(callee, T_SHORT); case vmIntrinsics::_putChar_raw : return append_unsafe_put_raw(callee, T_CHAR); case vmIntrinsics::_putInt_raw : return append_unsafe_put_raw(callee, T_INT); case vmIntrinsics::_putLong_raw : return append_unsafe_put_raw(callee, T_LONG); case vmIntrinsics::_putFloat_raw : return append_unsafe_put_raw(callee, T_FLOAT); case vmIntrinsics::_putDouble_raw : return append_unsafe_put_raw(callee, T_DOUBLE); case vmIntrinsics::_prefetchRead : return append_unsafe_prefetch(callee, false, false); case vmIntrinsics::_prefetchWrite : return append_unsafe_prefetch(callee, false, true); case vmIntrinsics::_prefetchReadStatic : return append_unsafe_prefetch(callee, true, false); case vmIntrinsics::_prefetchWriteStatic : return append_unsafe_prefetch(callee, true, true); case vmIntrinsics::_checkIndex : if (!InlineNIOCheckIndex) return false; preserves_state = true; break; case vmIntrinsics::_putOrderedObject : return append_unsafe_put_obj(callee, T_OBJECT, true); case vmIntrinsics::_putOrderedInt : return append_unsafe_put_obj(callee, T_INT, true); case vmIntrinsics::_putOrderedLong : return append_unsafe_put_obj(callee, T_LONG, true); case vmIntrinsics::_compareAndSwapLong: if (!VM_Version::supports_cx8()) return false; // fall through case vmIntrinsics::_compareAndSwapInt: case vmIntrinsics::_compareAndSwapObject: append_unsafe_CAS(callee); return true; case vmIntrinsics::_getAndAddInt: if (!VM_Version::supports_atomic_getadd4()) { return false; } return append_unsafe_get_and_set_obj(callee, true); case vmIntrinsics::_getAndAddLong: if (!VM_Version::supports_atomic_getadd8()) { return false; } return append_unsafe_get_and_set_obj(callee, true); case vmIntrinsics::_getAndSetInt: if (!VM_Version::supports_atomic_getset4()) { return false; } return append_unsafe_get_and_set_obj(callee, false); case vmIntrinsics::_getAndSetLong: if (!VM_Version::supports_atomic_getset8()) { return false; } return append_unsafe_get_and_set_obj(callee, false); case vmIntrinsics::_getAndSetObject: #ifdef _LP64 if (!UseCompressedOops && !VM_Version::supports_atomic_getset8()) { return false; } if (UseCompressedOops && !VM_Version::supports_atomic_getset4()) { return false; } #else if (!VM_Version::supports_atomic_getset4()) { return false; } #endif return append_unsafe_get_and_set_obj(callee, false); case vmIntrinsics::_Reference_get: // Use the intrinsic version of Reference.get() so that the value in // the referent field can be registered by the G1 pre-barrier code. // Also to prevent commoning reads from this field across safepoint // since GC can change its value. preserves_state = true; break; case vmIntrinsics::_updateCRC32: case vmIntrinsics::_updateBytesCRC32: case vmIntrinsics::_updateByteBufferCRC32: if (!UseCRC32Intrinsics) return false; cantrap = false; preserves_state = true; break; case vmIntrinsics::_loadFence : case vmIntrinsics::_storeFence: case vmIntrinsics::_fullFence : break; default : return false; // do not inline } // create intrinsic node const bool has_receiver = !callee->is_static(); ValueType* result_type = as_ValueType(callee->return_type()); ValueStack* state_before = copy_state_for_exception(); Values* args = state()->pop_arguments(callee->arg_size()); if (is_profiling()) { // Don't profile in the special case where the root method // is the intrinsic if (callee != method()) { // Note that we'd collect profile data in this method if we wanted it. compilation()->set_would_profile(true); if (profile_calls()) { Value recv = NULL; if (has_receiver) { recv = args->at(0); null_check(recv); } profile_call(callee, recv, NULL, collect_args_for_profiling(args, callee, true), true); } } } Intrinsic* result = new Intrinsic(result_type, id, args, has_receiver, state_before, preserves_state, cantrap); // append instruction & push result Value value = append_split(result); if (result_type != voidType) push(result_type, value); if (callee != method() && profile_return() && result_type->is_object_kind()) { profile_return_type(result, callee); } // done return true; } bool GraphBuilder::try_inline_jsr(int jsr_dest_bci) { // Introduce a new callee continuation point - all Ret instructions // will be replaced with Gotos to this point. BlockBegin* cont = block_at(next_bci()); assert(cont != NULL, "continuation must exist (BlockListBuilder starts a new block after a jsr"); // Note: can not assign state to continuation yet, as we have to // pick up the state from the Ret instructions. // Push callee scope push_scope_for_jsr(cont, jsr_dest_bci); // Temporarily set up bytecode stream so we can append instructions // (only using the bci of this stream) scope_data()->set_stream(scope_data()->parent()->stream()); BlockBegin* jsr_start_block = block_at(jsr_dest_bci); assert(jsr_start_block != NULL, "jsr start block must exist"); assert(!jsr_start_block->is_set(BlockBegin::was_visited_flag), "should not have visited jsr yet"); Goto* goto_sub = new Goto(jsr_start_block, false); // Must copy state to avoid wrong sharing when parsing bytecodes assert(jsr_start_block->state() == NULL, "should have fresh jsr starting block"); jsr_start_block->set_state(copy_state_before_with_bci(jsr_dest_bci)); append(goto_sub); _block->set_end(goto_sub); _last = _block = jsr_start_block; // Clear out bytecode stream scope_data()->set_stream(NULL); scope_data()->add_to_work_list(jsr_start_block); // Ready to resume parsing in subroutine iterate_all_blocks(); // If we bailed out during parsing, return immediately (this is bad news) CHECK_BAILOUT_(false); // Detect whether the continuation can actually be reached. If not, // it has not had state set by the join() operations in // iterate_bytecodes_for_block()/ret() and we should not touch the // iteration state. The calling activation of // iterate_bytecodes_for_block will then complete normally. if (cont->state() != NULL) { if (!cont->is_set(BlockBegin::was_visited_flag)) { // add continuation to work list instead of parsing it immediately scope_data()->parent()->add_to_work_list(cont); } } assert(jsr_continuation() == cont, "continuation must not have changed"); assert(!jsr_continuation()->is_set(BlockBegin::was_visited_flag) || jsr_continuation()->is_set(BlockBegin::parser_loop_header_flag), "continuation can only be visited in case of backward branches"); assert(_last && _last->as_BlockEnd(), "block must have end"); // continuation is in work list, so end iteration of current block _skip_block = true; pop_scope_for_jsr(); return true; } // Inline the entry of a synchronized method as a monitor enter and // register the exception handler which releases the monitor if an // exception is thrown within the callee. Note that the monitor enter // cannot throw an exception itself, because the receiver is // guaranteed to be non-null by the explicit null check at the // beginning of inlining. void GraphBuilder::inline_sync_entry(Value lock, BlockBegin* sync_handler) { assert(lock != NULL && sync_handler != NULL, "lock or handler missing"); monitorenter(lock, SynchronizationEntryBCI); assert(_last->as_MonitorEnter() != NULL, "monitor enter expected"); _last->set_needs_null_check(false); sync_handler->set(BlockBegin::exception_entry_flag); sync_handler->set(BlockBegin::is_on_work_list_flag); ciExceptionHandler* desc = new ciExceptionHandler(method()->holder(), 0, method()->code_size(), -1, 0); XHandler* h = new XHandler(desc); h->set_entry_block(sync_handler); scope_data()->xhandlers()->append(h); scope_data()->set_has_handler(); } // If an exception is thrown and not handled within an inlined // synchronized method, the monitor must be released before the // exception is rethrown in the outer scope. Generate the appropriate // instructions here. void GraphBuilder::fill_sync_handler(Value lock, BlockBegin* sync_handler, bool default_handler) { BlockBegin* orig_block = _block; ValueStack* orig_state = _state; Instruction* orig_last = _last; _last = _block = sync_handler; _state = sync_handler->state()->copy(); assert(sync_handler != NULL, "handler missing"); assert(!sync_handler->is_set(BlockBegin::was_visited_flag), "is visited here"); assert(lock != NULL || default_handler, "lock or handler missing"); XHandler* h = scope_data()->xhandlers()->remove_last(); assert(h->entry_block() == sync_handler, "corrupt list of handlers"); block()->set(BlockBegin::was_visited_flag); Value exception = append_with_bci(new ExceptionObject(), SynchronizationEntryBCI); assert(exception->is_pinned(), "must be"); int bci = SynchronizationEntryBCI; if (compilation()->env()->dtrace_method_probes()) { // Report exit from inline methods. We don't have a stream here // so pass an explicit bci of SynchronizationEntryBCI. Values* args = new Values(1); args->push(append_with_bci(new Constant(new MethodConstant(method())), bci)); append_with_bci(new RuntimeCall(voidType, "dtrace_method_exit", CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_exit), args), bci); } if (lock) { assert(state()->locks_size() > 0 && state()->lock_at(state()->locks_size() - 1) == lock, "lock is missing"); if (!lock->is_linked()) { lock = append_with_bci(lock, bci); } // exit the monitor in the context of the synchronized method monitorexit(lock, bci); // exit the context of the synchronized method if (!default_handler) { pop_scope(); bci = _state->caller_state()->bci(); _state = _state->caller_state()->copy_for_parsing(); } } // perform the throw as if at the the call site apush(exception); throw_op(bci); BlockEnd* end = last()->as_BlockEnd(); block()->set_end(end); _block = orig_block; _state = orig_state; _last = orig_last; } bool GraphBuilder::try_inline_full(ciMethod* callee, bool holder_known, Bytecodes::Code bc, Value receiver) { assert(!callee->is_native(), "callee must not be native"); if (CompilationPolicy::policy()->should_not_inline(compilation()->env(), callee)) { INLINE_BAILOUT("inlining prohibited by policy"); } // first perform tests of things it's not possible to inline if (callee->has_exception_handlers() && !InlineMethodsWithExceptionHandlers) INLINE_BAILOUT("callee has exception handlers"); if (callee->is_synchronized() && !InlineSynchronizedMethods ) INLINE_BAILOUT("callee is synchronized"); if (!callee->holder()->is_initialized()) INLINE_BAILOUT("callee's klass not initialized yet"); if (!callee->has_balanced_monitors()) INLINE_BAILOUT("callee's monitors do not match"); // Proper inlining of methods with jsrs requires a little more work. if (callee->has_jsrs() ) INLINE_BAILOUT("jsrs not handled properly by inliner yet"); // When SSE2 is used on intel, then no special handling is needed // for strictfp because the enum-constant is fixed at compile time, // the check for UseSSE2 is needed here if (strict_fp_requires_explicit_rounding && UseSSE < 2 && method()->is_strict() != callee->is_strict()) { INLINE_BAILOUT("caller and callee have different strict fp requirements"); } if (is_profiling() && !callee->ensure_method_data()) { INLINE_BAILOUT("mdo allocation failed"); } // now perform tests that are based on flag settings if (callee->force_inline()) { if (inline_level() > MaxForceInlineLevel) INLINE_BAILOUT("MaxForceInlineLevel"); print_inlining(callee, "force inline by annotation"); } else if (callee->should_inline()) { print_inlining(callee, "force inline by CompileOracle"); } else { // use heuristic controls on inlining if (inline_level() > MaxInlineLevel ) INLINE_BAILOUT("inlining too deep"); if (recursive_inline_level(callee) > MaxRecursiveInlineLevel) INLINE_BAILOUT("recursive inlining too deep"); if (callee->code_size_for_inlining() > max_inline_size() ) INLINE_BAILOUT("callee is too large"); // don't inline throwable methods unless the inlining tree is rooted in a throwable class if (callee->name() == ciSymbol::object_initializer_name() && callee->holder()->is_subclass_of(ciEnv::current()->Throwable_klass())) { // Throwable constructor call IRScope* top = scope(); while (top->caller() != NULL) { top = top->caller(); } if (!top->method()->holder()->is_subclass_of(ciEnv::current()->Throwable_klass())) { INLINE_BAILOUT("don't inline Throwable constructors"); } } if (compilation()->env()->num_inlined_bytecodes() > DesiredMethodLimit) { INLINE_BAILOUT("total inlining greater than DesiredMethodLimit"); } // printing print_inlining(callee); } // NOTE: Bailouts from this point on, which occur at the // GraphBuilder level, do not cause bailout just of the inlining but // in fact of the entire compilation. BlockBegin* orig_block = block(); const bool is_invokedynamic = bc == Bytecodes::_invokedynamic; const bool has_receiver = (bc != Bytecodes::_invokestatic && !is_invokedynamic); const int args_base = state()->stack_size() - callee->arg_size(); assert(args_base >= 0, "stack underflow during inlining"); // Insert null check if necessary Value recv = NULL; if (has_receiver) { // note: null check must happen even if first instruction of callee does // an implicit null check since the callee is in a different scope // and we must make sure exception handling does the right thing assert(!callee->is_static(), "callee must not be static"); assert(callee->arg_size() > 0, "must have at least a receiver"); recv = state()->stack_at(args_base); null_check(recv); } if (is_profiling()) { // Note that we'd collect profile data in this method if we wanted it. // this may be redundant here... compilation()->set_would_profile(true); if (profile_calls()) { int start = 0; Values* obj_args = args_list_for_profiling(callee, start, has_receiver); if (obj_args != NULL) { int s = obj_args->size(); // if called through method handle invoke, some arguments may have been popped for (int i = args_base+start, j = 0; j < obj_args->size() && i < state()->stack_size(); ) { Value v = state()->stack_at_inc(i); if (v->type()->is_object_kind()) { obj_args->push(v); j++; } } #ifdef ASSERT { bool ignored_will_link; ciSignature* declared_signature = NULL; ciMethod* real_target = method()->get_method_at_bci(bci(), ignored_will_link, &declared_signature); assert(s == obj_args->length() || real_target->is_method_handle_intrinsic(), "missed on arg?"); } #endif } profile_call(callee, recv, holder_known ? callee->holder() : NULL, obj_args, true); } } // Introduce a new callee continuation point - if the callee has // more than one return instruction or the return does not allow // fall-through of control flow, all return instructions of the // callee will need to be replaced by Goto's pointing to this // continuation point. BlockBegin* cont = block_at(next_bci()); bool continuation_existed = true; if (cont == NULL) { cont = new BlockBegin(next_bci()); // low number so that continuation gets parsed as early as possible cont->set_depth_first_number(0); #ifndef PRODUCT if (PrintInitialBlockList) { tty->print_cr("CFG: created block %d (bci %d) as continuation for inline at bci %d", cont->block_id(), cont->bci(), bci()); } #endif continuation_existed = false; } // Record number of predecessors of continuation block before // inlining, to detect if inlined method has edges to its // continuation after inlining. int continuation_preds = cont->number_of_preds(); // Push callee scope push_scope(callee, cont); // the BlockListBuilder for the callee could have bailed out if (bailed_out()) return false; // Temporarily set up bytecode stream so we can append instructions // (only using the bci of this stream) scope_data()->set_stream(scope_data()->parent()->stream()); // Pass parameters into callee state: add assignments // note: this will also ensure that all arguments are computed before being passed ValueStack* callee_state = state(); ValueStack* caller_state = state()->caller_state(); for (int i = args_base; i < caller_state->stack_size(); ) { const int arg_no = i - args_base; Value arg = caller_state->stack_at_inc(i); store_local(callee_state, arg, arg_no); } // Remove args from stack. // Note that we preserve locals state in case we can use it later // (see use of pop_scope() below) caller_state->truncate_stack(args_base); assert(callee_state->stack_size() == 0, "callee stack must be empty"); Value lock; BlockBegin* sync_handler; // Inline the locking of the receiver if the callee is synchronized if (callee->is_synchronized()) { lock = callee->is_static() ? append(new Constant(new InstanceConstant(callee->holder()->java_mirror()))) : state()->local_at(0); sync_handler = new BlockBegin(SynchronizationEntryBCI); inline_sync_entry(lock, sync_handler); } if (compilation()->env()->dtrace_method_probes()) { Values* args = new Values(1); args->push(append(new Constant(new MethodConstant(method())))); append(new RuntimeCall(voidType, "dtrace_method_entry", CAST_FROM_FN_PTR(address, SharedRuntime::dtrace_method_entry), args)); } if (profile_inlined_calls()) { profile_invocation(callee, copy_state_before_with_bci(SynchronizationEntryBCI)); } BlockBegin* callee_start_block = block_at(0); if (callee_start_block != NULL) { assert(callee_start_block->is_set(BlockBegin::parser_loop_header_flag), "must be loop header"); Goto* goto_callee = new Goto(callee_start_block, false); // The state for this goto is in the scope of the callee, so use // the entry bci for the callee instead of the call site bci. append_with_bci(goto_callee, 0); _block->set_end(goto_callee); callee_start_block->merge(callee_state); _last = _block = callee_start_block; scope_data()->add_to_work_list(callee_start_block); } // Clear out bytecode stream scope_data()->set_stream(NULL); // Ready to resume parsing in callee (either in the same block we // were in before or in the callee's start block) iterate_all_blocks(callee_start_block == NULL); // If we bailed out during parsing, return immediately (this is bad news) if (bailed_out()) return false; // iterate_all_blocks theoretically traverses in random order; in // practice, we have only traversed the continuation if we are // inlining into a subroutine assert(continuation_existed || !continuation()->is_set(BlockBegin::was_visited_flag), "continuation should not have been parsed yet if we created it"); // At this point we are almost ready to return and resume parsing of // the caller back in the GraphBuilder. The only thing we want to do // first is an optimization: during parsing of the callee we // generated at least one Goto to the continuation block. If we // generated exactly one, and if the inlined method spanned exactly // one block (and we didn't have to Goto its entry), then we snip // off the Goto to the continuation, allowing control to fall // through back into the caller block and effectively performing // block merging. This allows load elimination and CSE to take place // across multiple callee scopes if they are relatively simple, and // is currently essential to making inlining profitable. if (num_returns() == 1 && block() == orig_block && block() == inline_cleanup_block()) { _last = inline_cleanup_return_prev(); _state = inline_cleanup_state(); } else if (continuation_preds == cont->number_of_preds()) { // Inlining caused that the instructions after the invoke in the // caller are not reachable any more. So skip filling this block // with instructions! assert(cont == continuation(), ""); assert(_last && _last->as_BlockEnd(), ""); _skip_block = true; } else { // Resume parsing in continuation block unless it was already parsed. // Note that if we don't change _last here, iteration in // iterate_bytecodes_for_block will stop when we return. if (!continuation()->is_set(BlockBegin::was_visited_flag)) { // add continuation to work list instead of parsing it immediately assert(_last && _last->as_BlockEnd(), ""); scope_data()->parent()->add_to_work_list(continuation()); _skip_block = true; } } // Fill the exception handler for synchronized methods with instructions if (callee->is_synchronized() && sync_handler->state() != NULL) { fill_sync_handler(lock, sync_handler); } else { pop_scope(); } compilation()->notice_inlined_method(callee); return true; } bool GraphBuilder::try_method_handle_inline(ciMethod* callee) { ValueStack* state_before = state()->copy_for_parsing(); vmIntrinsics::ID iid = callee->intrinsic_id(); switch (iid) { case vmIntrinsics::_invokeBasic: { // get MethodHandle receiver const int args_base = state()->stack_size() - callee->arg_size(); ValueType* type = state()->stack_at(args_base)->type(); if (type->is_constant()) { ciMethod* target = type->as_ObjectType()->constant_value()->as_method_handle()->get_vmtarget(); // We don't do CHA here so only inline static and statically bindable methods. if (target->is_static() || target->can_be_statically_bound()) { Bytecodes::Code bc = target->is_static() ? Bytecodes::_invokestatic : Bytecodes::_invokevirtual; if (try_inline(target, /*holder_known*/ true, bc)) { return true; } } else { print_inlining(target, "not static or statically bindable", /*success*/ false); } } else { print_inlining(callee, "receiver not constant", /*success*/ false); } } break; case vmIntrinsics::_linkToVirtual: case vmIntrinsics::_linkToStatic: case vmIntrinsics::_linkToSpecial: case vmIntrinsics::_linkToInterface: { // pop MemberName argument const int args_base = state()->stack_size() - callee->arg_size(); ValueType* type = apop()->type(); if (type->is_constant()) { ciMethod* target = type->as_ObjectType()->constant_value()->as_member_name()->get_vmtarget(); // If the target is another method handle invoke try recursivly to get // a better target. if (target->is_method_handle_intrinsic()) { if (try_method_handle_inline(target)) { return true; } } else { ciSignature* signature = target->signature(); const int receiver_skip = target->is_static() ? 0 : 1; // Cast receiver to its type. if (!target->is_static()) { ciKlass* tk = signature->accessing_klass(); Value obj = state()->stack_at(args_base); if (obj->exact_type() == NULL && obj->declared_type() != tk && tk != compilation()->env()->Object_klass()) { TypeCast* c = new TypeCast(tk, obj, state_before); append(c); state()->stack_at_put(args_base, c); } } // Cast reference arguments to its type. for (int i = 0, j = 0; i < signature->count(); i++) { ciType* t = signature->type_at(i); if (t->is_klass()) { ciKlass* tk = t->as_klass(); Value obj = state()->stack_at(args_base + receiver_skip + j); if (obj->exact_type() == NULL && obj->declared_type() != tk && tk != compilation()->env()->Object_klass()) { TypeCast* c = new TypeCast(t, obj, state_before); append(c); state()->stack_at_put(args_base + receiver_skip + j, c); } } j += t->size(); // long and double take two slots } // We don't do CHA here so only inline static and statically bindable methods. if (target->is_static() || target->can_be_statically_bound()) { Bytecodes::Code bc = target->is_static() ? Bytecodes::_invokestatic : Bytecodes::_invokevirtual; if (try_inline(target, /*holder_known*/ true, bc)) { return true; } } else { print_inlining(target, "not static or statically bindable", /*success*/ false); } } } else { print_inlining(callee, "MemberName not constant", /*success*/ false); } } break; default: fatal(err_msg("unexpected intrinsic %d: %s", iid, vmIntrinsics::name_at(iid))); break; } set_state(state_before); return false; } void GraphBuilder::inline_bailout(const char* msg) { assert(msg != NULL, "inline bailout msg must exist"); _inline_bailout_msg = msg; } void GraphBuilder::clear_inline_bailout() { _inline_bailout_msg = NULL; } void GraphBuilder::push_root_scope(IRScope* scope, BlockList* bci2block, BlockBegin* start) { ScopeData* data = new ScopeData(NULL); data->set_scope(scope); data->set_bci2block(bci2block); _scope_data = data; _block = start; } void GraphBuilder::push_scope(ciMethod* callee, BlockBegin* continuation) { IRScope* callee_scope = new IRScope(compilation(), scope(), bci(), callee, -1, false); scope()->add_callee(callee_scope); BlockListBuilder blb(compilation(), callee_scope, -1); CHECK_BAILOUT(); if (!blb.bci2block()->at(0)->is_set(BlockBegin::parser_loop_header_flag)) { // this scope can be inlined directly into the caller so remove // the block at bci 0. blb.bci2block()->at_put(0, NULL); } set_state(new ValueStack(callee_scope, state()->copy(ValueStack::CallerState, bci()))); ScopeData* data = new ScopeData(scope_data()); data->set_scope(callee_scope); data->set_bci2block(blb.bci2block()); data->set_continuation(continuation); _scope_data = data; } void GraphBuilder::push_scope_for_jsr(BlockBegin* jsr_continuation, int jsr_dest_bci) { ScopeData* data = new ScopeData(scope_data()); data->set_parsing_jsr(); data->set_jsr_entry_bci(jsr_dest_bci); data->set_jsr_return_address_local(-1); // Must clone bci2block list as we will be mutating it in order to // properly clone all blocks in jsr region as well as exception // handlers containing rets BlockList* new_bci2block = new BlockList(bci2block()->length()); new_bci2block->push_all(bci2block()); data->set_bci2block(new_bci2block); data->set_scope(scope()); data->setup_jsr_xhandlers(); data->set_continuation(continuation()); data->set_jsr_continuation(jsr_continuation); _scope_data = data; } void GraphBuilder::pop_scope() { int number_of_locks = scope()->number_of_locks(); _scope_data = scope_data()->parent(); // accumulate minimum number of monitor slots to be reserved scope()->set_min_number_of_locks(number_of_locks); } void GraphBuilder::pop_scope_for_jsr() { _scope_data = scope_data()->parent(); } bool GraphBuilder::append_unsafe_get_obj(ciMethod* callee, BasicType t, bool is_volatile) { if (InlineUnsafeOps) { Values* args = state()->pop_arguments(callee->arg_size()); null_check(args->at(0)); Instruction* offset = args->at(2); #ifndef _LP64 offset = append(new Convert(Bytecodes::_l2i, offset, as_ValueType(T_INT))); #endif Instruction* op = append(new UnsafeGetObject(t, args->at(1), offset, is_volatile)); push(op->type(), op); compilation()->set_has_unsafe_access(true); } return InlineUnsafeOps; } bool GraphBuilder::append_unsafe_put_obj(ciMethod* callee, BasicType t, bool is_volatile) { if (InlineUnsafeOps) { Values* args = state()->pop_arguments(callee->arg_size()); null_check(args->at(0)); Instruction* offset = args->at(2); #ifndef _LP64 offset = append(new Convert(Bytecodes::_l2i, offset, as_ValueType(T_INT))); #endif Instruction* op = append(new UnsafePutObject(t, args->at(1), offset, args->at(3), is_volatile)); compilation()->set_has_unsafe_access(true); kill_all(); } return InlineUnsafeOps; } bool GraphBuilder::append_unsafe_get_raw(ciMethod* callee, BasicType t) { if (InlineUnsafeOps) { Values* args = state()->pop_arguments(callee->arg_size()); null_check(args->at(0)); Instruction* op = append(new UnsafeGetRaw(t, args->at(1), false)); push(op->type(), op); compilation()->set_has_unsafe_access(true); } return InlineUnsafeOps; } bool GraphBuilder::append_unsafe_put_raw(ciMethod* callee, BasicType t) { if (InlineUnsafeOps) { Values* args = state()->pop_arguments(callee->arg_size()); null_check(args->at(0)); Instruction* op = append(new UnsafePutRaw(t, args->at(1), args->at(2))); compilation()->set_has_unsafe_access(true); } return InlineUnsafeOps; } bool GraphBuilder::append_unsafe_prefetch(ciMethod* callee, bool is_static, bool is_store) { if (InlineUnsafeOps) { Values* args = state()->pop_arguments(callee->arg_size()); int obj_arg_index = 1; // Assume non-static case if (is_static) { obj_arg_index = 0; } else { null_check(args->at(0)); } Instruction* offset = args->at(obj_arg_index + 1); #ifndef _LP64 offset = append(new Convert(Bytecodes::_l2i, offset, as_ValueType(T_INT))); #endif Instruction* op = is_store ? append(new UnsafePrefetchWrite(args->at(obj_arg_index), offset)) : append(new UnsafePrefetchRead (args->at(obj_arg_index), offset)); compilation()->set_has_unsafe_access(true); } return InlineUnsafeOps; } void GraphBuilder::append_unsafe_CAS(ciMethod* callee) { ValueStack* state_before = copy_state_for_exception(); ValueType* result_type = as_ValueType(callee->return_type()); assert(result_type->is_int(), "int result"); Values* args = state()->pop_arguments(callee->arg_size()); // Pop off some args to speically handle, then push back Value newval = args->pop(); Value cmpval = args->pop(); Value offset = args->pop(); Value src = args->pop(); Value unsafe_obj = args->pop(); // Separately handle the unsafe arg. It is not needed for code // generation, but must be null checked null_check(unsafe_obj); #ifndef _LP64 offset = append(new Convert(Bytecodes::_l2i, offset, as_ValueType(T_INT))); #endif args->push(src); args->push(offset); args->push(cmpval); args->push(newval); // An unsafe CAS can alias with other field accesses, but we don't // know which ones so mark the state as no preserved. This will // cause CSE to invalidate memory across it. bool preserves_state = false; Intrinsic* result = new Intrinsic(result_type, callee->intrinsic_id(), args, false, state_before, preserves_state); append_split(result); push(result_type, result); compilation()->set_has_unsafe_access(true); } void GraphBuilder::print_inlining(ciMethod* callee, const char* msg, bool success) { CompileLog* log = compilation()->log(); if (log != NULL) { if (success) { if (msg != NULL) log->inline_success(msg); else log->inline_success("receiver is statically known"); } else { if (msg != NULL) log->inline_fail(msg); else log->inline_fail("reason unknown"); } } if (!PrintInlining && !compilation()->method()->has_option("PrintInlining")) { return; } CompileTask::print_inlining(callee, scope()->level(), bci(), msg); if (success && CIPrintMethodCodes) { callee->print_codes(); } } bool GraphBuilder::append_unsafe_get_and_set_obj(ciMethod* callee, bool is_add) { if (InlineUnsafeOps) { Values* args = state()->pop_arguments(callee->arg_size()); BasicType t = callee->return_type()->basic_type(); null_check(args->at(0)); Instruction* offset = args->at(2); #ifndef _LP64 offset = append(new Convert(Bytecodes::_l2i, offset, as_ValueType(T_INT))); #endif Instruction* op = append(new UnsafeGetAndSetObject(t, args->at(1), offset, args->at(3), is_add)); compilation()->set_has_unsafe_access(true); kill_all(); push(op->type(), op); } return InlineUnsafeOps; } #ifndef PRODUCT void GraphBuilder::print_stats() { vmap()->print(); } #endif // PRODUCT void GraphBuilder::profile_call(ciMethod* callee, Value recv, ciKlass* known_holder, Values* obj_args, bool inlined) { // A default method's holder is an interface if (known_holder != NULL && known_holder->is_interface()) { assert(known_holder->is_instance_klass() && ((ciInstanceKlass*)known_holder)->has_default_methods(), "should be default method"); known_holder = NULL; } append(new ProfileCall(method(), bci(), callee, recv, known_holder, obj_args, inlined)); } void GraphBuilder::profile_return_type(Value ret, ciMethod* callee, ciMethod* m, int invoke_bci) { assert((m == NULL) == (invoke_bci < 0), "invalid method and invalid bci together"); if (m == NULL) { m = method(); } if (invoke_bci < 0) { invoke_bci = bci(); } ciMethodData* md = m->method_data_or_null(); ciProfileData* data = md->bci_to_data(invoke_bci); if (data->is_CallTypeData() || data->is_VirtualCallTypeData()) { append(new ProfileReturnType(m , invoke_bci, callee, ret)); } } void GraphBuilder::profile_invocation(ciMethod* callee, ValueStack* state) { append(new ProfileInvoke(callee, state)); } Other Java examples (source code examples)Here is a short list of links related to this Java c1_GraphBuilder.cpp source code file: |
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