1071 lines
34 KiB
C++
1071 lines
34 KiB
C++
/*
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* Copyright (c) 1998, 2011, Oracle and/or its affiliates. All rights reserved.
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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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*
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* This code is free software; you can redistribute it and/or modify it
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* under the terms of the GNU General Public License version 2 only, as
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* published by the Free Software Foundation.
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*
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* This code is distributed in the hope that it will be useful, but WITHOUT
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* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
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* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
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* version 2 for more details (a copy is included in the LICENSE file that
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* accompanied this code).
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*
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* You should have received a copy of the GNU General Public License version
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* 2 along with this work; if not, write to the Free Software Foundation,
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* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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*
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* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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* or visit www.oracle.com if you need additional information or have any
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* questions.
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*
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*/
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#include "precompiled.hpp"
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#include "ci/ciMethod.hpp"
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#include "ci/ciMethodBlocks.hpp"
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#include "ci/ciStreams.hpp"
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#include "compiler/methodLiveness.hpp"
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#include "interpreter/bytecode.hpp"
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#include "interpreter/bytecodes.hpp"
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#include "memory/allocation.inline.hpp"
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#include "utilities/bitMap.inline.hpp"
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// The MethodLiveness class performs a simple liveness analysis on a method
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// in order to decide which locals are live (that is, will be used again) at
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// a particular bytecode index (bci).
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//
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// The algorithm goes:
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//
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// 1. Break the method into a set of basic blocks. For each basic block we
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// also keep track of its set of predecessors through normal control flow
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// and predecessors through exceptional control flow.
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//
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// 2. For each basic block, compute two sets, gen (the set of values used before
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// they are defined) and kill (the set of values defined before they are used)
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// in the basic block. A basic block "needs" the locals in its gen set to
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// perform its computation. A basic block "provides" values for the locals in
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// its kill set, allowing a need from a successor to be ignored.
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//
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// 3. Liveness information (the set of locals which are needed) is pushed backwards through
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// the program, from blocks to their predecessors. We compute and store liveness
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// information for the normal/exceptional exit paths for each basic block. When
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// this process reaches a fixed point, we are done.
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//
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// 4. When we are asked about the liveness at a particular bci with a basic block, we
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// compute gen/kill sets which represent execution from that bci to the exit of
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// its blocks. We then compose this range gen/kill information with the normal
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// and exceptional exit information for the block to produce liveness information
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// at that bci.
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//
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// The algorithm is approximate in many respects. Notably:
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//
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// 1. We do not do the analysis necessary to match jsr's with the appropriate ret.
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// Instead we make the conservative assumption that any ret can return to any
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// jsr return site.
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// 2. Instead of computing the effects of exceptions at every instruction, we
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// summarize the effects of all exceptional continuations from the block as
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// a single set (_exception_exit), losing some information but simplifying the
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// analysis.
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//--------------------------------------------------------------------------
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// The BitCounter class is used for counting the number of bits set in
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// some BitMap. It is only used when collecting liveness statistics.
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#ifndef PRODUCT
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class BitCounter: public BitMapClosure {
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private:
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int _count;
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public:
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BitCounter() : _count(0) {}
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// Callback when bit in map is set
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virtual bool do_bit(size_t offset) {
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_count++;
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return true;
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}
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int count() {
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return _count;
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}
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};
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//--------------------------------------------------------------------------
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// Counts
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long MethodLiveness::_total_bytes = 0;
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int MethodLiveness::_total_methods = 0;
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long MethodLiveness::_total_blocks = 0;
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int MethodLiveness::_max_method_blocks = 0;
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long MethodLiveness::_total_edges = 0;
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int MethodLiveness::_max_block_edges = 0;
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long MethodLiveness::_total_exc_edges = 0;
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int MethodLiveness::_max_block_exc_edges = 0;
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long MethodLiveness::_total_method_locals = 0;
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int MethodLiveness::_max_method_locals = 0;
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long MethodLiveness::_total_locals_queried = 0;
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long MethodLiveness::_total_live_locals_queried = 0;
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long MethodLiveness::_total_visits = 0;
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#endif
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// Timers
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elapsedTimer MethodLiveness::_time_build_graph;
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elapsedTimer MethodLiveness::_time_gen_kill;
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elapsedTimer MethodLiveness::_time_flow;
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elapsedTimer MethodLiveness::_time_query;
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elapsedTimer MethodLiveness::_time_total;
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MethodLiveness::MethodLiveness(Arena* arena, ciMethod* method)
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#ifdef COMPILER1
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: _bci_block_start((uintptr_t*)arena->Amalloc((method->code_size() >> LogBitsPerByte) + 1), method->code_size())
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#endif
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{
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_arena = arena;
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_method = method;
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_bit_map_size_bits = method->max_locals();
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_bit_map_size_words = (_bit_map_size_bits / sizeof(unsigned int)) + 1;
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#ifdef COMPILER1
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_bci_block_start.clear();
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#endif
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}
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void MethodLiveness::compute_liveness() {
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#ifndef PRODUCT
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if (TraceLivenessGen) {
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tty->print_cr("################################################################");
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tty->print("# Computing liveness information for ");
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method()->print_short_name();
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}
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if (TimeLivenessAnalysis) _time_total.start();
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#endif
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{
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TraceTime buildGraph(NULL, &_time_build_graph, TimeLivenessAnalysis);
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init_basic_blocks();
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}
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{
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TraceTime genKill(NULL, &_time_gen_kill, TimeLivenessAnalysis);
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init_gen_kill();
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}
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{
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TraceTime flow(NULL, &_time_flow, TimeLivenessAnalysis);
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propagate_liveness();
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}
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#ifndef PRODUCT
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if (TimeLivenessAnalysis) _time_total.stop();
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if (TimeLivenessAnalysis) {
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// Collect statistics
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_total_bytes += method()->code_size();
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_total_methods++;
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int num_blocks = _block_count;
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_total_blocks += num_blocks;
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_max_method_blocks = MAX2(num_blocks,_max_method_blocks);
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for (int i=0; i<num_blocks; i++) {
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BasicBlock *block = _block_list[i];
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int numEdges = block->_normal_predecessors->length();
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int numExcEdges = block->_exception_predecessors->length();
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_total_edges += numEdges;
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_total_exc_edges += numExcEdges;
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_max_block_edges = MAX2(numEdges,_max_block_edges);
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_max_block_exc_edges = MAX2(numExcEdges,_max_block_exc_edges);
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}
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int numLocals = _bit_map_size_bits;
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_total_method_locals += numLocals;
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_max_method_locals = MAX2(numLocals,_max_method_locals);
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}
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#endif
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}
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void MethodLiveness::init_basic_blocks() {
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bool bailout = false;
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int method_len = method()->code_size();
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ciMethodBlocks *mblocks = method()->get_method_blocks();
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// Create an array to store the bci->BasicBlock mapping.
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_block_map = new (arena()) GrowableArray<BasicBlock*>(arena(), method_len, method_len, NULL);
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_block_count = mblocks->num_blocks();
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_block_list = (BasicBlock **) arena()->Amalloc(sizeof(BasicBlock *) * _block_count);
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// Used for patching up jsr/ret control flow.
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GrowableArray<BasicBlock*>* jsr_exit_list = new GrowableArray<BasicBlock*>(5);
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GrowableArray<BasicBlock*>* ret_list = new GrowableArray<BasicBlock*>(5);
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// generate our block list from ciMethodBlocks
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for (int blk = 0; blk < _block_count; blk++) {
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ciBlock *cib = mblocks->block(blk);
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int start_bci = cib->start_bci();
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_block_list[blk] = new (arena()) BasicBlock(this, start_bci, cib->limit_bci());
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_block_map->at_put(start_bci, _block_list[blk]);
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#ifdef COMPILER1
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// mark all bcis where a new basic block starts
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_bci_block_start.set_bit(start_bci);
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#endif // COMPILER1
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}
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// fill in the predecessors of blocks
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ciBytecodeStream bytes(method());
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for (int blk = 0; blk < _block_count; blk++) {
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BasicBlock *current_block = _block_list[blk];
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int bci = mblocks->block(blk)->control_bci();
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if (bci == ciBlock::fall_through_bci) {
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int limit = current_block->limit_bci();
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if (limit < method_len) {
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BasicBlock *next = _block_map->at(limit);
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assert( next != NULL, "must be a block immediately following this one.");
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next->add_normal_predecessor(current_block);
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}
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continue;
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}
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bytes.reset_to_bci(bci);
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Bytecodes::Code code = bytes.next();
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BasicBlock *dest;
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// Now we need to interpret the instruction's effect
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// on control flow.
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assert (current_block != NULL, "we must have a current block");
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switch (code) {
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case Bytecodes::_ifeq:
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case Bytecodes::_ifne:
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case Bytecodes::_iflt:
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case Bytecodes::_ifge:
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case Bytecodes::_ifgt:
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case Bytecodes::_ifle:
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case Bytecodes::_if_icmpeq:
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case Bytecodes::_if_icmpne:
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case Bytecodes::_if_icmplt:
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case Bytecodes::_if_icmpge:
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case Bytecodes::_if_icmpgt:
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case Bytecodes::_if_icmple:
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case Bytecodes::_if_acmpeq:
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case Bytecodes::_if_acmpne:
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case Bytecodes::_ifnull:
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case Bytecodes::_ifnonnull:
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// Two way branch. Set predecessors at each destination.
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dest = _block_map->at(bytes.next_bci());
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assert(dest != NULL, "must be a block immediately following this one.");
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dest->add_normal_predecessor(current_block);
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dest = _block_map->at(bytes.get_dest());
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assert(dest != NULL, "branch desination must start a block.");
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dest->add_normal_predecessor(current_block);
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break;
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case Bytecodes::_goto:
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dest = _block_map->at(bytes.get_dest());
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assert(dest != NULL, "branch desination must start a block.");
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dest->add_normal_predecessor(current_block);
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break;
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case Bytecodes::_goto_w:
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dest = _block_map->at(bytes.get_far_dest());
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assert(dest != NULL, "branch desination must start a block.");
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dest->add_normal_predecessor(current_block);
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break;
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case Bytecodes::_tableswitch:
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{
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Bytecode_tableswitch tableswitch(&bytes);
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int len = tableswitch.length();
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dest = _block_map->at(bci + tableswitch.default_offset());
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assert(dest != NULL, "branch desination must start a block.");
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dest->add_normal_predecessor(current_block);
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while (--len >= 0) {
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dest = _block_map->at(bci + tableswitch.dest_offset_at(len));
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assert(dest != NULL, "branch desination must start a block.");
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dest->add_normal_predecessor(current_block);
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}
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break;
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}
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case Bytecodes::_lookupswitch:
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{
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Bytecode_lookupswitch lookupswitch(&bytes);
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int npairs = lookupswitch.number_of_pairs();
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dest = _block_map->at(bci + lookupswitch.default_offset());
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assert(dest != NULL, "branch desination must start a block.");
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dest->add_normal_predecessor(current_block);
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while(--npairs >= 0) {
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LookupswitchPair pair = lookupswitch.pair_at(npairs);
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dest = _block_map->at( bci + pair.offset());
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assert(dest != NULL, "branch desination must start a block.");
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dest->add_normal_predecessor(current_block);
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}
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break;
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}
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case Bytecodes::_jsr:
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{
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assert(bytes.is_wide()==false, "sanity check");
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dest = _block_map->at(bytes.get_dest());
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assert(dest != NULL, "branch desination must start a block.");
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dest->add_normal_predecessor(current_block);
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BasicBlock *jsrExit = _block_map->at(current_block->limit_bci());
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assert(jsrExit != NULL, "jsr return bci must start a block.");
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jsr_exit_list->append(jsrExit);
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break;
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}
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case Bytecodes::_jsr_w:
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{
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dest = _block_map->at(bytes.get_far_dest());
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assert(dest != NULL, "branch desination must start a block.");
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dest->add_normal_predecessor(current_block);
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BasicBlock *jsrExit = _block_map->at(current_block->limit_bci());
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assert(jsrExit != NULL, "jsr return bci must start a block.");
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jsr_exit_list->append(jsrExit);
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break;
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}
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case Bytecodes::_wide:
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assert(false, "wide opcodes should not be seen here");
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break;
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case Bytecodes::_athrow:
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case Bytecodes::_ireturn:
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case Bytecodes::_lreturn:
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case Bytecodes::_freturn:
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case Bytecodes::_dreturn:
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case Bytecodes::_areturn:
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case Bytecodes::_return:
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// These opcodes are not the normal predecessors of any other opcodes.
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break;
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case Bytecodes::_ret:
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// We will patch up jsr/rets in a subsequent pass.
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ret_list->append(current_block);
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break;
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case Bytecodes::_breakpoint:
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// Bail out of there are breakpoints in here.
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bailout = true;
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break;
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default:
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// Do nothing.
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break;
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}
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}
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// Patch up the jsr/ret's. We conservatively assume that any ret
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// can return to any jsr site.
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int ret_list_len = ret_list->length();
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int jsr_exit_list_len = jsr_exit_list->length();
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if (ret_list_len > 0 && jsr_exit_list_len > 0) {
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for (int i = jsr_exit_list_len - 1; i >= 0; i--) {
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BasicBlock *jsrExit = jsr_exit_list->at(i);
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for (int i = ret_list_len - 1; i >= 0; i--) {
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jsrExit->add_normal_predecessor(ret_list->at(i));
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}
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}
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}
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// Compute exception edges.
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for (int b=_block_count-1; b >= 0; b--) {
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BasicBlock *block = _block_list[b];
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int block_start = block->start_bci();
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int block_limit = block->limit_bci();
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ciExceptionHandlerStream handlers(method());
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for (; !handlers.is_done(); handlers.next()) {
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ciExceptionHandler* handler = handlers.handler();
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int start = handler->start();
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int limit = handler->limit();
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int handler_bci = handler->handler_bci();
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int intersect_start = MAX2(block_start, start);
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int intersect_limit = MIN2(block_limit, limit);
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if (intersect_start < intersect_limit) {
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// The catch range has a nonempty intersection with this
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// basic block. That means this basic block can be an
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// exceptional predecessor.
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_block_map->at(handler_bci)->add_exception_predecessor(block);
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if (handler->is_catch_all()) {
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// This is a catch-all block.
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if (intersect_start == block_start && intersect_limit == block_limit) {
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// The basic block is entirely contained in this catch-all block.
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// Skip the rest of the exception handlers -- they can never be
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// reached in execution.
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break;
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}
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}
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}
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}
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}
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}
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void MethodLiveness::init_gen_kill() {
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for (int i=_block_count-1; i >= 0; i--) {
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_block_list[i]->compute_gen_kill(method());
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}
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}
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void MethodLiveness::propagate_liveness() {
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int num_blocks = _block_count;
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BasicBlock *block;
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// We start our work list off with all blocks in it.
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// Alternately, we could start off the work list with the list of all
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// blocks which could exit the method directly, along with one block
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// from any infinite loop. If this matters, it can be changed. It
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// may not be clear from looking at the code, but the order of the
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// workList will be the opposite of the creation order of the basic
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// blocks, which should be decent for quick convergence (with the
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// possible exception of exception handlers, which are all created
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// early).
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_work_list = NULL;
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for (int i = 0; i < num_blocks; i++) {
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block = _block_list[i];
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block->set_next(_work_list);
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block->set_on_work_list(true);
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_work_list = block;
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}
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while ((block = work_list_get()) != NULL) {
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block->propagate(this);
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NOT_PRODUCT(_total_visits++;)
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}
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}
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void MethodLiveness::work_list_add(BasicBlock *block) {
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if (!block->on_work_list()) {
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block->set_next(_work_list);
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block->set_on_work_list(true);
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_work_list = block;
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}
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}
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MethodLiveness::BasicBlock *MethodLiveness::work_list_get() {
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BasicBlock *block = _work_list;
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if (block != NULL) {
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block->set_on_work_list(false);
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_work_list = block->next();
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}
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return block;
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}
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MethodLivenessResult MethodLiveness::get_liveness_at(int entry_bci) {
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int bci = entry_bci;
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bool is_entry = false;
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if (entry_bci == InvocationEntryBci) {
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is_entry = true;
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bci = 0;
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}
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MethodLivenessResult answer((uintptr_t*)NULL,0);
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if (_block_count > 0) {
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if (TimeLivenessAnalysis) _time_total.start();
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if (TimeLivenessAnalysis) _time_query.start();
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assert( 0 <= bci && bci < method()->code_size(), "bci out of range" );
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BasicBlock *block = _block_map->at(bci);
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// We may not be at the block start, so search backwards to find the block
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// containing bci.
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int t = bci;
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while (block == NULL && t > 0) {
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block = _block_map->at(--t);
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}
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|
assert( block != NULL, "invalid bytecode index; must be instruction index" );
|
|
assert(bci >= block->start_bci() && bci < block->limit_bci(), "block must contain bci.");
|
|
|
|
answer = block->get_liveness_at(method(), bci);
|
|
|
|
if (is_entry && method()->is_synchronized() && !method()->is_static()) {
|
|
// Synchronized methods use the receiver once on entry.
|
|
answer.at_put(0, true);
|
|
}
|
|
|
|
#ifndef PRODUCT
|
|
if (TraceLivenessQuery) {
|
|
tty->print("Liveness query of ");
|
|
method()->print_short_name();
|
|
tty->print(" @ %d : result is ", bci);
|
|
answer.print_on(tty);
|
|
}
|
|
|
|
if (TimeLivenessAnalysis) _time_query.stop();
|
|
if (TimeLivenessAnalysis) _time_total.stop();
|
|
#endif
|
|
}
|
|
|
|
#ifndef PRODUCT
|
|
if (TimeLivenessAnalysis) {
|
|
// Collect statistics.
|
|
_total_locals_queried += _bit_map_size_bits;
|
|
BitCounter counter;
|
|
answer.iterate(&counter);
|
|
_total_live_locals_queried += counter.count();
|
|
}
|
|
#endif
|
|
|
|
return answer;
|
|
}
|
|
|
|
|
|
#ifndef PRODUCT
|
|
|
|
void MethodLiveness::print_times() {
|
|
tty->print_cr ("Accumulated liveness analysis times/statistics:");
|
|
tty->print_cr ("-----------------------------------------------");
|
|
tty->print_cr (" Total : %3.3f sec.", _time_total.seconds());
|
|
tty->print_cr (" Build graph : %3.3f sec. (%2.2f%%)", _time_build_graph.seconds(),
|
|
_time_build_graph.seconds() * 100 / _time_total.seconds());
|
|
tty->print_cr (" Gen / Kill : %3.3f sec. (%2.2f%%)", _time_gen_kill.seconds(),
|
|
_time_gen_kill.seconds() * 100 / _time_total.seconds());
|
|
tty->print_cr (" Dataflow : %3.3f sec. (%2.2f%%)", _time_flow.seconds(),
|
|
_time_flow.seconds() * 100 / _time_total.seconds());
|
|
tty->print_cr (" Query : %3.3f sec. (%2.2f%%)", _time_query.seconds(),
|
|
_time_query.seconds() * 100 / _time_total.seconds());
|
|
tty->print_cr (" #bytes : %8d (%3.0f bytes per sec)",
|
|
_total_bytes,
|
|
_total_bytes / _time_total.seconds());
|
|
tty->print_cr (" #methods : %8d (%3.0f methods per sec)",
|
|
_total_methods,
|
|
_total_methods / _time_total.seconds());
|
|
tty->print_cr (" avg locals : %3.3f max locals : %3d",
|
|
(float)_total_method_locals / _total_methods,
|
|
_max_method_locals);
|
|
tty->print_cr (" avg blocks : %3.3f max blocks : %3d",
|
|
(float)_total_blocks / _total_methods,
|
|
_max_method_blocks);
|
|
tty->print_cr (" avg bytes : %3.3f",
|
|
(float)_total_bytes / _total_methods);
|
|
tty->print_cr (" #blocks : %8d",
|
|
_total_blocks);
|
|
tty->print_cr (" avg normal predecessors : %3.3f max normal predecessors : %3d",
|
|
(float)_total_edges / _total_blocks,
|
|
_max_block_edges);
|
|
tty->print_cr (" avg exception predecessors : %3.3f max exception predecessors : %3d",
|
|
(float)_total_exc_edges / _total_blocks,
|
|
_max_block_exc_edges);
|
|
tty->print_cr (" avg visits : %3.3f",
|
|
(float)_total_visits / _total_blocks);
|
|
tty->print_cr (" #locals queried : %8d #live : %8d %%live : %2.2f%%",
|
|
_total_locals_queried,
|
|
_total_live_locals_queried,
|
|
100.0 * _total_live_locals_queried / _total_locals_queried);
|
|
}
|
|
|
|
#endif
|
|
|
|
|
|
MethodLiveness::BasicBlock::BasicBlock(MethodLiveness *analyzer, int start, int limit) :
|
|
_gen((uintptr_t*)analyzer->arena()->Amalloc(BytesPerWord * analyzer->bit_map_size_words()),
|
|
analyzer->bit_map_size_bits()),
|
|
_kill((uintptr_t*)analyzer->arena()->Amalloc(BytesPerWord * analyzer->bit_map_size_words()),
|
|
analyzer->bit_map_size_bits()),
|
|
_entry((uintptr_t*)analyzer->arena()->Amalloc(BytesPerWord * analyzer->bit_map_size_words()),
|
|
analyzer->bit_map_size_bits()),
|
|
_normal_exit((uintptr_t*)analyzer->arena()->Amalloc(BytesPerWord * analyzer->bit_map_size_words()),
|
|
analyzer->bit_map_size_bits()),
|
|
_exception_exit((uintptr_t*)analyzer->arena()->Amalloc(BytesPerWord * analyzer->bit_map_size_words()),
|
|
analyzer->bit_map_size_bits()),
|
|
_last_bci(-1) {
|
|
_analyzer = analyzer;
|
|
_start_bci = start;
|
|
_limit_bci = limit;
|
|
_normal_predecessors =
|
|
new (analyzer->arena()) GrowableArray<MethodLiveness::BasicBlock*>(analyzer->arena(), 5, 0, NULL);
|
|
_exception_predecessors =
|
|
new (analyzer->arena()) GrowableArray<MethodLiveness::BasicBlock*>(analyzer->arena(), 5, 0, NULL);
|
|
_normal_exit.clear();
|
|
_exception_exit.clear();
|
|
_entry.clear();
|
|
|
|
// this initialization is not strictly necessary.
|
|
// _gen and _kill are cleared at the beginning of compute_gen_kill_range()
|
|
_gen.clear();
|
|
_kill.clear();
|
|
}
|
|
|
|
|
|
|
|
MethodLiveness::BasicBlock *MethodLiveness::BasicBlock::split(int split_bci) {
|
|
int start = _start_bci;
|
|
int limit = _limit_bci;
|
|
|
|
if (TraceLivenessGen) {
|
|
tty->print_cr(" ** Splitting block (%d,%d) at %d", start, limit, split_bci);
|
|
}
|
|
|
|
GrowableArray<BasicBlock*>* save_predecessors = _normal_predecessors;
|
|
|
|
assert (start < split_bci && split_bci < limit, "improper split");
|
|
|
|
// Make a new block to cover the first half of the range.
|
|
BasicBlock *first_half = new (_analyzer->arena()) BasicBlock(_analyzer, start, split_bci);
|
|
|
|
// Assign correct values to the second half (this)
|
|
_normal_predecessors = first_half->_normal_predecessors;
|
|
_start_bci = split_bci;
|
|
add_normal_predecessor(first_half);
|
|
|
|
// Assign correct predecessors to the new first half
|
|
first_half->_normal_predecessors = save_predecessors;
|
|
|
|
return first_half;
|
|
}
|
|
|
|
void MethodLiveness::BasicBlock::compute_gen_kill(ciMethod* method) {
|
|
ciBytecodeStream bytes(method);
|
|
bytes.reset_to_bci(start_bci());
|
|
bytes.set_max_bci(limit_bci());
|
|
compute_gen_kill_range(&bytes);
|
|
|
|
}
|
|
|
|
void MethodLiveness::BasicBlock::compute_gen_kill_range(ciBytecodeStream *bytes) {
|
|
_gen.clear();
|
|
_kill.clear();
|
|
|
|
while (bytes->next() != ciBytecodeStream::EOBC()) {
|
|
compute_gen_kill_single(bytes);
|
|
}
|
|
}
|
|
|
|
void MethodLiveness::BasicBlock::compute_gen_kill_single(ciBytecodeStream *instruction) {
|
|
int localNum;
|
|
|
|
// We prohibit _gen and _kill from having locals in common. If we
|
|
// know that one is definitely going to be applied before the other,
|
|
// we could save some computation time by relaxing this prohibition.
|
|
|
|
switch (instruction->cur_bc()) {
|
|
case Bytecodes::_nop:
|
|
case Bytecodes::_goto:
|
|
case Bytecodes::_goto_w:
|
|
case Bytecodes::_aconst_null:
|
|
case Bytecodes::_new:
|
|
case Bytecodes::_iconst_m1:
|
|
case Bytecodes::_iconst_0:
|
|
case Bytecodes::_iconst_1:
|
|
case Bytecodes::_iconst_2:
|
|
case Bytecodes::_iconst_3:
|
|
case Bytecodes::_iconst_4:
|
|
case Bytecodes::_iconst_5:
|
|
case Bytecodes::_fconst_0:
|
|
case Bytecodes::_fconst_1:
|
|
case Bytecodes::_fconst_2:
|
|
case Bytecodes::_bipush:
|
|
case Bytecodes::_sipush:
|
|
case Bytecodes::_lconst_0:
|
|
case Bytecodes::_lconst_1:
|
|
case Bytecodes::_dconst_0:
|
|
case Bytecodes::_dconst_1:
|
|
case Bytecodes::_ldc2_w:
|
|
case Bytecodes::_ldc:
|
|
case Bytecodes::_ldc_w:
|
|
case Bytecodes::_iaload:
|
|
case Bytecodes::_faload:
|
|
case Bytecodes::_baload:
|
|
case Bytecodes::_caload:
|
|
case Bytecodes::_saload:
|
|
case Bytecodes::_laload:
|
|
case Bytecodes::_daload:
|
|
case Bytecodes::_aaload:
|
|
case Bytecodes::_iastore:
|
|
case Bytecodes::_fastore:
|
|
case Bytecodes::_bastore:
|
|
case Bytecodes::_castore:
|
|
case Bytecodes::_sastore:
|
|
case Bytecodes::_lastore:
|
|
case Bytecodes::_dastore:
|
|
case Bytecodes::_aastore:
|
|
case Bytecodes::_pop:
|
|
case Bytecodes::_pop2:
|
|
case Bytecodes::_dup:
|
|
case Bytecodes::_dup_x1:
|
|
case Bytecodes::_dup_x2:
|
|
case Bytecodes::_dup2:
|
|
case Bytecodes::_dup2_x1:
|
|
case Bytecodes::_dup2_x2:
|
|
case Bytecodes::_swap:
|
|
case Bytecodes::_iadd:
|
|
case Bytecodes::_fadd:
|
|
case Bytecodes::_isub:
|
|
case Bytecodes::_fsub:
|
|
case Bytecodes::_imul:
|
|
case Bytecodes::_fmul:
|
|
case Bytecodes::_idiv:
|
|
case Bytecodes::_fdiv:
|
|
case Bytecodes::_irem:
|
|
case Bytecodes::_frem:
|
|
case Bytecodes::_ishl:
|
|
case Bytecodes::_ishr:
|
|
case Bytecodes::_iushr:
|
|
case Bytecodes::_iand:
|
|
case Bytecodes::_ior:
|
|
case Bytecodes::_ixor:
|
|
case Bytecodes::_l2f:
|
|
case Bytecodes::_l2i:
|
|
case Bytecodes::_d2f:
|
|
case Bytecodes::_d2i:
|
|
case Bytecodes::_fcmpl:
|
|
case Bytecodes::_fcmpg:
|
|
case Bytecodes::_ladd:
|
|
case Bytecodes::_dadd:
|
|
case Bytecodes::_lsub:
|
|
case Bytecodes::_dsub:
|
|
case Bytecodes::_lmul:
|
|
case Bytecodes::_dmul:
|
|
case Bytecodes::_ldiv:
|
|
case Bytecodes::_ddiv:
|
|
case Bytecodes::_lrem:
|
|
case Bytecodes::_drem:
|
|
case Bytecodes::_land:
|
|
case Bytecodes::_lor:
|
|
case Bytecodes::_lxor:
|
|
case Bytecodes::_ineg:
|
|
case Bytecodes::_fneg:
|
|
case Bytecodes::_i2f:
|
|
case Bytecodes::_f2i:
|
|
case Bytecodes::_i2c:
|
|
case Bytecodes::_i2s:
|
|
case Bytecodes::_i2b:
|
|
case Bytecodes::_lneg:
|
|
case Bytecodes::_dneg:
|
|
case Bytecodes::_l2d:
|
|
case Bytecodes::_d2l:
|
|
case Bytecodes::_lshl:
|
|
case Bytecodes::_lshr:
|
|
case Bytecodes::_lushr:
|
|
case Bytecodes::_i2l:
|
|
case Bytecodes::_i2d:
|
|
case Bytecodes::_f2l:
|
|
case Bytecodes::_f2d:
|
|
case Bytecodes::_lcmp:
|
|
case Bytecodes::_dcmpl:
|
|
case Bytecodes::_dcmpg:
|
|
case Bytecodes::_ifeq:
|
|
case Bytecodes::_ifne:
|
|
case Bytecodes::_iflt:
|
|
case Bytecodes::_ifge:
|
|
case Bytecodes::_ifgt:
|
|
case Bytecodes::_ifle:
|
|
case Bytecodes::_tableswitch:
|
|
case Bytecodes::_ireturn:
|
|
case Bytecodes::_freturn:
|
|
case Bytecodes::_if_icmpeq:
|
|
case Bytecodes::_if_icmpne:
|
|
case Bytecodes::_if_icmplt:
|
|
case Bytecodes::_if_icmpge:
|
|
case Bytecodes::_if_icmpgt:
|
|
case Bytecodes::_if_icmple:
|
|
case Bytecodes::_lreturn:
|
|
case Bytecodes::_dreturn:
|
|
case Bytecodes::_if_acmpeq:
|
|
case Bytecodes::_if_acmpne:
|
|
case Bytecodes::_jsr:
|
|
case Bytecodes::_jsr_w:
|
|
case Bytecodes::_getstatic:
|
|
case Bytecodes::_putstatic:
|
|
case Bytecodes::_getfield:
|
|
case Bytecodes::_putfield:
|
|
case Bytecodes::_invokevirtual:
|
|
case Bytecodes::_invokespecial:
|
|
case Bytecodes::_invokestatic:
|
|
case Bytecodes::_invokeinterface:
|
|
case Bytecodes::_invokedynamic:
|
|
case Bytecodes::_newarray:
|
|
case Bytecodes::_anewarray:
|
|
case Bytecodes::_checkcast:
|
|
case Bytecodes::_arraylength:
|
|
case Bytecodes::_instanceof:
|
|
case Bytecodes::_athrow:
|
|
case Bytecodes::_areturn:
|
|
case Bytecodes::_monitorenter:
|
|
case Bytecodes::_monitorexit:
|
|
case Bytecodes::_ifnull:
|
|
case Bytecodes::_ifnonnull:
|
|
case Bytecodes::_multianewarray:
|
|
case Bytecodes::_lookupswitch:
|
|
// These bytecodes have no effect on the method's locals.
|
|
break;
|
|
|
|
case Bytecodes::_return:
|
|
if (instruction->method()->intrinsic_id() == vmIntrinsics::_Object_init) {
|
|
// return from Object.init implicitly registers a finalizer
|
|
// for the receiver if needed, so keep it alive.
|
|
load_one(0);
|
|
}
|
|
break;
|
|
|
|
|
|
case Bytecodes::_lload:
|
|
case Bytecodes::_dload:
|
|
load_two(instruction->get_index());
|
|
break;
|
|
|
|
case Bytecodes::_lload_0:
|
|
case Bytecodes::_dload_0:
|
|
load_two(0);
|
|
break;
|
|
|
|
case Bytecodes::_lload_1:
|
|
case Bytecodes::_dload_1:
|
|
load_two(1);
|
|
break;
|
|
|
|
case Bytecodes::_lload_2:
|
|
case Bytecodes::_dload_2:
|
|
load_two(2);
|
|
break;
|
|
|
|
case Bytecodes::_lload_3:
|
|
case Bytecodes::_dload_3:
|
|
load_two(3);
|
|
break;
|
|
|
|
case Bytecodes::_iload:
|
|
case Bytecodes::_iinc:
|
|
case Bytecodes::_fload:
|
|
case Bytecodes::_aload:
|
|
case Bytecodes::_ret:
|
|
load_one(instruction->get_index());
|
|
break;
|
|
|
|
case Bytecodes::_iload_0:
|
|
case Bytecodes::_fload_0:
|
|
case Bytecodes::_aload_0:
|
|
load_one(0);
|
|
break;
|
|
|
|
case Bytecodes::_iload_1:
|
|
case Bytecodes::_fload_1:
|
|
case Bytecodes::_aload_1:
|
|
load_one(1);
|
|
break;
|
|
|
|
case Bytecodes::_iload_2:
|
|
case Bytecodes::_fload_2:
|
|
case Bytecodes::_aload_2:
|
|
load_one(2);
|
|
break;
|
|
|
|
case Bytecodes::_iload_3:
|
|
case Bytecodes::_fload_3:
|
|
case Bytecodes::_aload_3:
|
|
load_one(3);
|
|
break;
|
|
|
|
case Bytecodes::_lstore:
|
|
case Bytecodes::_dstore:
|
|
store_two(localNum = instruction->get_index());
|
|
break;
|
|
|
|
case Bytecodes::_lstore_0:
|
|
case Bytecodes::_dstore_0:
|
|
store_two(0);
|
|
break;
|
|
|
|
case Bytecodes::_lstore_1:
|
|
case Bytecodes::_dstore_1:
|
|
store_two(1);
|
|
break;
|
|
|
|
case Bytecodes::_lstore_2:
|
|
case Bytecodes::_dstore_2:
|
|
store_two(2);
|
|
break;
|
|
|
|
case Bytecodes::_lstore_3:
|
|
case Bytecodes::_dstore_3:
|
|
store_two(3);
|
|
break;
|
|
|
|
case Bytecodes::_istore:
|
|
case Bytecodes::_fstore:
|
|
case Bytecodes::_astore:
|
|
store_one(instruction->get_index());
|
|
break;
|
|
|
|
case Bytecodes::_istore_0:
|
|
case Bytecodes::_fstore_0:
|
|
case Bytecodes::_astore_0:
|
|
store_one(0);
|
|
break;
|
|
|
|
case Bytecodes::_istore_1:
|
|
case Bytecodes::_fstore_1:
|
|
case Bytecodes::_astore_1:
|
|
store_one(1);
|
|
break;
|
|
|
|
case Bytecodes::_istore_2:
|
|
case Bytecodes::_fstore_2:
|
|
case Bytecodes::_astore_2:
|
|
store_one(2);
|
|
break;
|
|
|
|
case Bytecodes::_istore_3:
|
|
case Bytecodes::_fstore_3:
|
|
case Bytecodes::_astore_3:
|
|
store_one(3);
|
|
break;
|
|
|
|
case Bytecodes::_wide:
|
|
fatal("Iterator should skip this bytecode");
|
|
break;
|
|
|
|
default:
|
|
tty->print("unexpected opcode: %d\n", instruction->cur_bc());
|
|
ShouldNotReachHere();
|
|
break;
|
|
}
|
|
}
|
|
|
|
void MethodLiveness::BasicBlock::load_two(int local) {
|
|
load_one(local);
|
|
load_one(local+1);
|
|
}
|
|
|
|
void MethodLiveness::BasicBlock::load_one(int local) {
|
|
if (!_kill.at(local)) {
|
|
_gen.at_put(local, true);
|
|
}
|
|
}
|
|
|
|
void MethodLiveness::BasicBlock::store_two(int local) {
|
|
store_one(local);
|
|
store_one(local+1);
|
|
}
|
|
|
|
void MethodLiveness::BasicBlock::store_one(int local) {
|
|
if (!_gen.at(local)) {
|
|
_kill.at_put(local, true);
|
|
}
|
|
}
|
|
|
|
void MethodLiveness::BasicBlock::propagate(MethodLiveness *ml) {
|
|
// These set operations could be combined for efficiency if the
|
|
// performance of this analysis becomes an issue.
|
|
_entry.set_union(_normal_exit);
|
|
_entry.set_difference(_kill);
|
|
_entry.set_union(_gen);
|
|
|
|
// Note that we merge information from our exceptional successors
|
|
// just once, rather than at individual bytecodes.
|
|
_entry.set_union(_exception_exit);
|
|
|
|
if (TraceLivenessGen) {
|
|
tty->print_cr(" ** Visiting block at %d **", start_bci());
|
|
print_on(tty);
|
|
}
|
|
|
|
int i;
|
|
for (i=_normal_predecessors->length()-1; i>=0; i--) {
|
|
BasicBlock *block = _normal_predecessors->at(i);
|
|
if (block->merge_normal(_entry)) {
|
|
ml->work_list_add(block);
|
|
}
|
|
}
|
|
for (i=_exception_predecessors->length()-1; i>=0; i--) {
|
|
BasicBlock *block = _exception_predecessors->at(i);
|
|
if (block->merge_exception(_entry)) {
|
|
ml->work_list_add(block);
|
|
}
|
|
}
|
|
}
|
|
|
|
bool MethodLiveness::BasicBlock::merge_normal(BitMap other) {
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|
return _normal_exit.set_union_with_result(other);
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|
}
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|
|
|
bool MethodLiveness::BasicBlock::merge_exception(BitMap other) {
|
|
return _exception_exit.set_union_with_result(other);
|
|
}
|
|
|
|
MethodLivenessResult MethodLiveness::BasicBlock::get_liveness_at(ciMethod* method, int bci) {
|
|
MethodLivenessResult answer(NEW_RESOURCE_ARRAY(uintptr_t, _analyzer->bit_map_size_words()),
|
|
_analyzer->bit_map_size_bits());
|
|
answer.set_is_valid();
|
|
|
|
#ifndef ASSERT
|
|
if (bci == start_bci()) {
|
|
answer.set_from(_entry);
|
|
return answer;
|
|
}
|
|
#endif
|
|
|
|
#ifdef ASSERT
|
|
ResourceMark rm;
|
|
BitMap g(_gen.size()); g.set_from(_gen);
|
|
BitMap k(_kill.size()); k.set_from(_kill);
|
|
#endif
|
|
if (_last_bci != bci || trueInDebug) {
|
|
ciBytecodeStream bytes(method);
|
|
bytes.reset_to_bci(bci);
|
|
bytes.set_max_bci(limit_bci());
|
|
compute_gen_kill_range(&bytes);
|
|
assert(_last_bci != bci ||
|
|
(g.is_same(_gen) && k.is_same(_kill)), "cached computation is incorrect");
|
|
_last_bci = bci;
|
|
}
|
|
|
|
answer.clear();
|
|
answer.set_union(_normal_exit);
|
|
answer.set_difference(_kill);
|
|
answer.set_union(_gen);
|
|
answer.set_union(_exception_exit);
|
|
|
|
#ifdef ASSERT
|
|
if (bci == start_bci()) {
|
|
assert(answer.is_same(_entry), "optimized answer must be accurate");
|
|
}
|
|
#endif
|
|
|
|
return answer;
|
|
}
|
|
|
|
#ifndef PRODUCT
|
|
|
|
void MethodLiveness::BasicBlock::print_on(outputStream *os) const {
|
|
os->print_cr("===================================================================");
|
|
os->print_cr(" Block start: %4d, limit: %4d", _start_bci, _limit_bci);
|
|
os->print (" Normal predecessors (%2d) @", _normal_predecessors->length());
|
|
int i;
|
|
for (i=0; i < _normal_predecessors->length(); i++) {
|
|
os->print(" %4d", _normal_predecessors->at(i)->start_bci());
|
|
}
|
|
os->cr();
|
|
os->print (" Exceptional predecessors (%2d) @", _exception_predecessors->length());
|
|
for (i=0; i < _exception_predecessors->length(); i++) {
|
|
os->print(" %4d", _exception_predecessors->at(i)->start_bci());
|
|
}
|
|
os->cr();
|
|
os->print (" Normal Exit : ");
|
|
_normal_exit.print_on(os);
|
|
os->print (" Gen : ");
|
|
_gen.print_on(os);
|
|
os->print (" Kill : ");
|
|
_kill.print_on(os);
|
|
os->print (" Exception Exit: ");
|
|
_exception_exit.print_on(os);
|
|
os->print (" Entry : ");
|
|
_entry.print_on(os);
|
|
}
|
|
|
|
#endif // PRODUCT
|