1 /* 2 * Copyright (c) 2005, 2019, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25 #ifndef SHARE_CI_BCESCAPEANALYZER_HPP 26 #define SHARE_CI_BCESCAPEANALYZER_HPP 27 28 #ifdef COMPILER2 29 #include "ci/ciObject.hpp" 30 #include "ci/ciMethod.hpp" 31 #include "ci/ciMethodData.hpp" 32 #include "code/dependencies.hpp" 33 #include "libadt/vectset.hpp" 34 #include "memory/allocation.hpp" 35 #include "utilities/growableArray.hpp" 36 #endif 37 38 // This class implements a fast, conservative analysis of effect of methods 39 // on the escape state of their arguments. The analysis is at the bytecode 40 // level. 41 42 class ciMethodBlocks; 43 class ciBlock; 44 45 class BCEscapeAnalyzer : public ResourceObj { 46 private: 47 Arena* _arena; // ciEnv arena 48 49 bool _conservative; // If true, return maximally 50 // conservative results. 51 ciMethod* _method; 52 ciMethodData* _methodData; 53 int _arg_size; 54 VectorSet _arg_local; 55 VectorSet _arg_stack; 56 VectorSet _arg_returned; 57 VectorSet _dirty; 58 enum{ ARG_OFFSET_MAX = 31}; 59 uint *_arg_modified; 60 61 bool _return_local; 62 bool _return_allocated; 63 bool _allocated_escapes; 64 bool _unknown_modified; 65 66 GrowableArray<ciMetadata*> _dependencies; 67 68 ciMethodBlocks *_methodBlocks; 69 70 BCEscapeAnalyzer* _parent; 71 int _level; 72 73 public: 74 class ArgumentMap; 75 class StateInfo; 76 77 private: 78 // helper functions is_argument(int i)79 bool is_argument(int i) { return i >= 0 && i < _arg_size; } 80 void set_returned(ArgumentMap vars); 81 bool is_argument(ArgumentMap vars); 82 bool is_arg_stack(ArgumentMap vars); 83 bool returns_all(ArgumentMap vars); 84 void clear_bits(ArgumentMap vars, VectorSet &bs); 85 void set_method_escape(ArgumentMap vars); 86 void set_global_escape(ArgumentMap vars, bool merge = false); 87 void set_dirty(ArgumentMap vars); 88 void set_modified(ArgumentMap vars, int offs, int size); 89 90 bool is_recursive_call(ciMethod* callee); 91 void invoke(StateInfo &state, Bytecodes::Code code, ciMethod* target, ciKlass* holder); 92 93 void iterate_one_block(ciBlock *blk, StateInfo &state, GrowableArray<ciBlock *> &successors); 94 void iterate_blocks(Arena *); 95 void merge_block_states(StateInfo *blockstates, ciBlock *dest, StateInfo *s_state); 96 97 // analysis 98 void initialize(); 99 void clear_escape_info(); 100 void compute_escape_info(); 101 vmIntrinsics::ID known_intrinsic(); 102 void compute_escape_for_intrinsic(vmIntrinsics::ID iid); 103 void do_analysis(); 104 105 void read_escape_info(); 106 107 bool contains(uint arg_set1, uint arg_set2); 108 109 public: 110 BCEscapeAnalyzer(ciMethod* method, BCEscapeAnalyzer* parent = NULL); 111 112 // accessors method() const113 ciMethod* method() const { return _method; } methodData() const114 ciMethodData* methodData() const { return _methodData; } parent() const115 BCEscapeAnalyzer* parent() const { return _parent; } level() const116 int level() const { return _level; } dependencies()117 GrowableArray<ciMetadata *>* dependencies() { return &_dependencies; } has_dependencies() const118 bool has_dependencies() const { return !_dependencies.is_empty(); } 119 120 // retrieval of interprocedural escape information 121 122 // The given argument does not escape the callee. is_arg_local(int i) const123 bool is_arg_local(int i) const { 124 return !_conservative && _arg_local.test(i); 125 } 126 127 // The given argument escapes the callee, but does not become globally 128 // reachable. is_arg_stack(int i) const129 bool is_arg_stack(int i) const { 130 return !_conservative && _arg_stack.test(i); 131 } 132 133 // The given argument does not escape globally, and may be returned. is_arg_returned(int i) const134 bool is_arg_returned(int i) const { 135 return !_conservative && _arg_returned.test(i); } 136 137 // True iff only input arguments are returned. is_return_local() const138 bool is_return_local() const { 139 return !_conservative && _return_local; 140 } 141 142 // True iff only newly allocated unescaped objects are returned. is_return_allocated() const143 bool is_return_allocated() const { 144 return !_conservative && _return_allocated && !_allocated_escapes; 145 } 146 147 // Tracking of argument modification 148 149 enum {OFFSET_ANY = -1}; 150 bool is_arg_modified(int arg, int offset, int size_in_bytes); 151 void set_arg_modified(int arg, int offset, int size_in_bytes); has_non_arg_side_affects()152 bool has_non_arg_side_affects() { return _unknown_modified; } 153 154 // Copy dependencies from this analysis into "deps" 155 void copy_dependencies(Dependencies *deps); 156 157 #ifndef PRODUCT 158 // dump escape information 159 void dump(); 160 #endif 161 }; 162 163 #endif // SHARE_CI_BCESCAPEANALYZER_HPP 164