1 /* 2 * Copyright (c) 1999, 2023, 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 #include "precompiled.hpp" 26 #include "c1/c1_IR.hpp" 27 #include "c1/c1_InstructionPrinter.hpp" 28 #include "c1/c1_ValueStack.hpp" 29 30 31 // Implementation of ValueStack 32 33 ValueStack::ValueStack(IRScope* scope, ValueStack* caller_state) 34 : _scope(scope) 35 , _caller_state(caller_state) 36 , _bci(-99) 37 , _kind(Parsing) 38 , _locals(scope->method()->max_locals(), scope->method()->max_locals(), nullptr) 39 , _stack(scope->method()->max_stack()) 40 , _locks(nullptr) 41 { 42 verify(); 43 } 44 45 ValueStack::ValueStack(ValueStack* copy_from, Kind kind, int bci) 46 : _scope(copy_from->scope()) 47 , _caller_state(copy_from->caller_state()) 48 , _bci(bci) 49 , _kind(kind) 50 , _locals(copy_from->locals_size_for_copy(kind)) 51 , _stack(copy_from->stack_size_for_copy(kind)) 52 , _locks(copy_from->locks_size() == 0 ? nullptr : new Values(copy_from->locks_size())) 53 { 54 switch (kind) { 55 case EmptyExceptionState: 56 case CallerEmptyExceptionState: 57 assert(!Compilation::current()->env()->should_retain_local_variables(), "need locals"); 58 // set to all nulls, like clear_locals() 59 for (int i = 0; i < copy_from->locals_size(); ++i) { 60 _locals.append(nullptr); 61 } 62 break; 63 default: 64 _locals.appendAll(©_from->_locals); 65 } 66 67 switch (kind) { 68 case ExceptionState: 69 case EmptyExceptionState: 70 assert(stack_size() == 0, "fix stack_size_for_copy"); 71 break; 72 case CallerExceptionState: 73 case CallerEmptyExceptionState: 74 // set to all nulls 75 for (int i = 0; i < copy_from->stack_size(); ++i) { 76 _stack.append(nullptr); 77 } 78 break; 79 default: 80 _stack.appendAll(©_from->_stack); 81 } 82 83 if (copy_from->locks_size() > 0) { 84 _locks->appendAll(copy_from->_locks); 85 } 86 87 verify(); 88 } 89 90 int ValueStack::locals_size_for_copy(Kind kind) const { 91 return locals_size(); 92 } 93 94 int ValueStack::stack_size_for_copy(Kind kind) const { 95 if (kind != ExceptionState && kind != EmptyExceptionState) { 96 if (kind == Parsing) { 97 // stack will be modified, so reserve enough space to avoid resizing 98 return scope()->method()->max_stack(); 99 } else { 100 // stack will not be modified, so do not waste space 101 return stack_size(); 102 } 103 } 104 return 0; 105 } 106 107 bool ValueStack::is_same(ValueStack* s) { 108 if (scope() != s->scope()) return false; 109 if (caller_state() != s->caller_state()) return false; 110 111 if (locals_size() != s->locals_size()) return false; 112 if (stack_size() != s->stack_size()) return false; 113 if (locks_size() != s->locks_size()) return false; 114 115 // compare each stack element with the corresponding stack element of s 116 int index; 117 Value value; 118 for_each_stack_value(this, index, value) { 119 if (value->type()->tag() != s->stack_at(index)->type()->tag()) return false; 120 } 121 for (int i = 0; i < locks_size(); i++) { 122 value = lock_at(i); 123 if (value != nullptr && value != s->lock_at(i)) { 124 return false; 125 } 126 } 127 return true; 128 } 129 130 void ValueStack::clear_locals() { 131 for (int i = _locals.length() - 1; i >= 0; i--) { 132 _locals.at_put(i, nullptr); 133 } 134 } 135 136 137 void ValueStack::pin_stack_for_linear_scan() { 138 for_each_state_value(this, v, 139 if (v->as_Constant() == nullptr && v->as_Local() == nullptr) { 140 v->pin(Instruction::PinStackForStateSplit); 141 } 142 ); 143 } 144 145 146 // apply function to all values of a list; factored out from values_do(f) 147 void ValueStack::apply(const Values& list, ValueVisitor* f) { 148 for (int i = 0; i < list.length(); i++) { 149 Value* va = list.adr_at(i); 150 Value v0 = *va; 151 if (v0 != nullptr && !v0->type()->is_illegal()) { 152 f->visit(va); 153 #ifdef ASSERT 154 Value v1 = *va; 155 assert(v1->type()->is_illegal() || v0->type()->tag() == v1->type()->tag(), "types must match"); 156 assert(!v1->type()->is_double_word() || list.at(i + 1) == nullptr, "hi-word of doubleword value must be null"); 157 #endif 158 if (v0->type()->is_double_word()) i++; 159 } 160 } 161 } 162 163 164 void ValueStack::values_do(ValueVisitor* f) { 165 ValueStack* state = this; 166 for_each_state(state) { 167 apply(state->_locals, f); 168 apply(state->_stack, f); 169 if (state->_locks != nullptr) { 170 apply(*state->_locks, f); 171 } 172 } 173 } 174 175 176 Values* ValueStack::pop_arguments(int argument_size) { 177 assert(stack_size() >= argument_size, "stack too small or too many arguments"); 178 int base = stack_size() - argument_size; 179 Values* args = new Values(argument_size); 180 for (int i = base; i < stack_size();) args->push(stack_at_inc(i)); 181 truncate_stack(base); 182 return args; 183 } 184 185 186 int ValueStack::total_locks_size() const { 187 int num_locks = 0; 188 const ValueStack* state = this; 189 for_each_state(state) { 190 num_locks += state->locks_size(); 191 } 192 return num_locks; 193 } 194 195 int ValueStack::lock(Value obj) { 196 if (_locks == nullptr) { 197 _locks = new Values(); 198 } 199 _locks->push(obj); 200 int num_locks = total_locks_size(); 201 scope()->set_min_number_of_locks(num_locks); 202 return num_locks - 1; 203 } 204 205 206 int ValueStack::unlock() { 207 assert(locks_size() > 0, "sanity"); 208 _locks->pop(); 209 return total_locks_size(); 210 } 211 212 213 void ValueStack::setup_phi_for_stack(BlockBegin* b, int index) { 214 assert(stack_at(index)->as_Phi() == nullptr || stack_at(index)->as_Phi()->block() != b, "phi function already created"); 215 216 ValueType* t = stack_at(index)->type(); 217 Value phi = new Phi(t, b, -index - 1); 218 _stack.at_put(index, phi); 219 220 assert(!t->is_double_word() || _stack.at(index + 1) == nullptr, "hi-word of doubleword value must be null"); 221 } 222 223 void ValueStack::setup_phi_for_local(BlockBegin* b, int index) { 224 assert(local_at(index)->as_Phi() == nullptr || local_at(index)->as_Phi()->block() != b, "phi function already created"); 225 226 ValueType* t = local_at(index)->type(); 227 Value phi = new Phi(t, b, index); 228 store_local(index, phi); 229 } 230 231 #ifndef PRODUCT 232 233 void ValueStack::print() { 234 scope()->method()->print_name(); 235 tty->cr(); 236 if (stack_is_empty()) { 237 tty->print_cr("empty stack"); 238 } else { 239 InstructionPrinter ip; 240 for (int i = 0; i < stack_size();) { 241 tty->print("stack %d ", i); 242 Value t = stack_at_inc(i); 243 if (t == nullptr) { 244 tty->print("null"); 245 } else { 246 tty->print("%2d ", i); 247 tty->print("%c%d ", t->type()->tchar(), t->id()); 248 ip.print_instr(t); 249 } 250 tty->cr(); 251 } 252 } 253 if (!no_active_locks()) { 254 InstructionPrinter ip; 255 for (int i = 0; i < locks_size(); i++) { 256 Value t = lock_at(i); 257 tty->print("lock %2d ", i); 258 if (t == nullptr) { 259 tty->print("this"); 260 } else { 261 tty->print("%c%d ", t->type()->tchar(), t->id()); 262 ip.print_instr(t); 263 } 264 tty->cr(); 265 } 266 } 267 if (locals_size() > 0) { 268 InstructionPrinter ip; 269 for (int i = 0; i < locals_size();) { 270 Value l = _locals.at(i); 271 tty->print("local %d ", i); 272 if (l == nullptr) { 273 tty->print("null"); 274 i ++; 275 } else { 276 tty->print("%c%d ", l->type()->tchar(), l->id()); 277 ip.print_instr(l); 278 if (l->type()->is_illegal() || l->type()->is_single_word()) i ++; else i += 2; 279 } 280 tty->cr(); 281 } 282 } 283 284 if (caller_state() != nullptr) { 285 caller_state()->print(); 286 } 287 } 288 289 290 void ValueStack::verify() { 291 assert(scope() != nullptr, "scope must exist"); 292 if (caller_state() != nullptr) { 293 assert(caller_state()->scope() == scope()->caller(), "invalid caller scope"); 294 caller_state()->verify(); 295 } 296 297 if (kind() == Parsing) { 298 assert(bci() == -99, "bci not defined during parsing"); 299 } else { 300 assert(bci() >= -1, "bci out of range"); 301 assert(bci() < scope()->method()->code_size(), "bci out of range"); 302 assert(bci() == SynchronizationEntryBCI || Bytecodes::is_defined(scope()->method()->java_code_at_bci(bci())), "make sure bci points at a real bytecode"); 303 assert(scope()->method()->liveness_at_bci(bci()).is_valid(), "liveness at bci must be valid"); 304 } 305 306 int i; 307 for (i = 0; i < stack_size(); i++) { 308 Value v = _stack.at(i); 309 if (kind() == empty_exception_kind(true /* caller */)) { 310 assert(v == nullptr, "should be empty"); 311 } else if (v == nullptr) { 312 assert(_stack.at(i - 1)->type()->is_double_word(), "only hi-words are null on stack"); 313 } else if (v->type()->is_double_word()) { 314 assert(_stack.at(i + 1) == nullptr, "hi-word must be null"); 315 } 316 } 317 318 for (i = 0; i < locals_size(); i++) { 319 Value v = _locals.at(i); 320 if (kind() == EmptyExceptionState) { 321 assert(v == nullptr, "should be empty"); 322 } else if (v != nullptr && v->type()->is_double_word()) { 323 assert(_locals.at(i + 1) == nullptr, "hi-word must be null"); 324 } 325 } 326 327 for_each_state_value(this, v, 328 assert(v != nullptr, "just test if state-iteration succeeds"); 329 ); 330 } 331 #endif // PRODUCT