1 /* 2 * Copyright (c) 1998, 2010, 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_VM_COMPILER_OOPMAP_HPP 26 #define SHARE_VM_COMPILER_OOPMAP_HPP 27 28 #include "code/compressedStream.hpp" 29 #include "code/vmreg.hpp" 30 #include "memory/allocation.hpp" 31 #include "utilities/growableArray.hpp" 32 33 // Interface for generating the frame map for compiled code. A frame map 34 // describes for a specific pc whether each register and frame stack slot is: 35 // Oop - A GC root for current frame 36 // Dead - Dead; can be Zapped for debugging 37 // CalleeXX - Callee saved; also describes which caller register is saved 38 // DerivedXX - A derived oop; original oop is described. 39 // 40 // OopMapValue describes a single OopMap entry 41 42 class frame; 43 class RegisterMap; 44 class DerivedPointerEntry; 45 46 class OopMapValue: public StackObj { 47 friend class VMStructs; 48 private: 49 short _value; 50 int value() const { return _value; } 51 void set_value(int value) { _value = value; } 52 short _content_reg; 53 54 public: 55 // Constants 56 enum { type_bits = 4, 57 register_bits = BitsPerShort - type_bits }; 58 59 enum { type_shift = 0, 60 register_shift = type_bits }; 61 62 enum { type_mask = right_n_bits(type_bits), 63 type_mask_in_place = type_mask << type_shift, 64 register_mask = right_n_bits(register_bits), 65 register_mask_in_place = register_mask << register_shift }; 66 67 enum oop_types { // must fit in type_bits 68 unused_value =0, // powers of 2, for masking OopMapStream 69 oop_value = 1, 70 narrowoop_value = 2, 71 callee_saved_value = 4, 72 derived_oop_value= 8 }; 73 74 // Constructors 75 OopMapValue () { set_value(0); set_content_reg(VMRegImpl::Bad()); } 76 OopMapValue (VMReg reg, oop_types t) { set_reg_type(reg,t); } 77 OopMapValue (VMReg reg, oop_types t, VMReg reg2) { set_reg_type(reg,t); set_content_reg(reg2); } 78 OopMapValue (CompressedReadStream* stream) { read_from(stream); } 79 80 // Archiving 81 void write_on(CompressedWriteStream* stream) { 82 stream->write_int(value()); 83 if(is_callee_saved() || is_derived_oop()) { 84 stream->write_int(content_reg()->value()); 85 } 86 } 87 88 void read_from(CompressedReadStream* stream) { 89 set_value(stream->read_int()); 90 if(is_callee_saved() || is_derived_oop()) { 91 set_content_reg(VMRegImpl::as_VMReg(stream->read_int(), true)); 92 } 93 } 94 95 // Querying 96 bool is_oop() { return mask_bits(value(), type_mask_in_place) == oop_value; } 97 bool is_narrowoop() { return mask_bits(value(), type_mask_in_place) == narrowoop_value; } 98 bool is_callee_saved() { return mask_bits(value(), type_mask_in_place) == callee_saved_value; } 99 bool is_derived_oop() { return mask_bits(value(), type_mask_in_place) == derived_oop_value; } 100 101 void set_oop() { set_value((value() & register_mask_in_place) | oop_value); } 102 void set_narrowoop() { set_value((value() & register_mask_in_place) | narrowoop_value); } 103 void set_callee_saved() { set_value((value() & register_mask_in_place) | callee_saved_value); } 104 void set_derived_oop() { set_value((value() & register_mask_in_place) | derived_oop_value); } 105 106 VMReg reg() const { return VMRegImpl::as_VMReg(mask_bits(value(), register_mask_in_place) >> register_shift); } 107 oop_types type() const { return (oop_types)mask_bits(value(), type_mask_in_place); } 108 109 static bool legal_vm_reg_name(VMReg p) { 110 return (p->value() == (p->value() & register_mask)); 111 } 112 113 void set_reg_type(VMReg p, oop_types t) { 114 set_value((p->value() << register_shift) | t); 115 assert(reg() == p, "sanity check" ); 116 assert(type() == t, "sanity check" ); 117 } 118 119 120 VMReg content_reg() const { return VMRegImpl::as_VMReg(_content_reg, true); } 121 void set_content_reg(VMReg r) { _content_reg = r->value(); } 122 123 // Physical location queries 124 bool is_register_loc() { return reg()->is_reg(); } 125 bool is_stack_loc() { return reg()->is_stack(); } 126 127 // Returns offset from sp. 128 int stack_offset() { 129 assert(is_stack_loc(), "must be stack location"); 130 return reg()->reg2stack(); 131 } 132 133 void print_on(outputStream* st) const; 134 void print() const { print_on(tty); } 135 }; 136 137 138 class OopMap: public ResourceObj { 139 friend class OopMapStream; 140 friend class VMStructs; 141 private: 142 int _pc_offset; // offset in the code that this OopMap corresponds to 143 int _omv_count; // number of OopMapValues in the stream 144 CompressedWriteStream* _write_stream; 145 146 debug_only( OopMapValue::oop_types* _locs_used; int _locs_length;) 147 148 // Accessors 149 int omv_count() const { return _omv_count; } 150 void set_omv_count(int value) { _omv_count = value; } 151 void increment_count() { _omv_count++; } 152 CompressedWriteStream* write_stream() const { return _write_stream; } 153 void set_write_stream(CompressedWriteStream* value) { _write_stream = value; } 154 155 private: 156 enum DeepCopyToken { _deep_copy_token }; 157 OopMap(DeepCopyToken, OopMap* source); // used only by deep_copy 158 159 public: 160 OopMap(int frame_size, int arg_count); 161 162 // pc-offset handling 163 int offset() const { return _pc_offset; } 164 void set_offset(int o) { _pc_offset = o; } 165 int count() const { return _omv_count; } 166 int data_size() const { return write_stream()->position(); } 167 address data() const { return write_stream()->buffer(); } 168 169 // Check to avoid double insertion 170 debug_only(OopMapValue::oop_types locs_used( int indx ) { return _locs_used[indx]; }) 171 172 // Construction 173 // frame_size units are stack-slots (4 bytes) NOT intptr_t; we can name odd 174 // slots to hold 4-byte values like ints and floats in the LP64 build. 175 void set_oop ( VMReg local); 176 void set_value( VMReg local); 177 void set_narrowoop(VMReg local); 178 void set_dead ( VMReg local); 179 void set_callee_saved( VMReg local, VMReg caller_machine_register ); 180 void set_derived_oop ( VMReg local, VMReg derived_from_local_register ); 181 void set_xxx(VMReg reg, OopMapValue::oop_types x, VMReg optional); 182 183 int heap_size() const; 184 void copy_data_to(address addr) const; 185 OopMap* deep_copy(); 186 187 bool legal_vm_reg_name(VMReg local) { 188 return OopMapValue::legal_vm_reg_name(local); 189 } 190 191 // Printing 192 void print_on(outputStream* st) const; 193 void print() const { print_on(tty); } 194 bool equals(const OopMap* other) const; 195 }; 196 197 198 class OopMapSet : public ResourceObj { 199 friend class VMStructs; 200 private: 201 int _om_count; 202 int _om_size; 203 OopMap** _om_data; 204 205 int om_count() const { return _om_count; } 206 void set_om_count(int value) { _om_count = value; } 207 void increment_count() { _om_count++; } 208 int om_size() const { return _om_size; } 209 void set_om_size(int value) { _om_size = value; } 210 OopMap** om_data() const { return _om_data; } 211 void set_om_data(OopMap** value) { _om_data = value; } 212 void grow_om_data(); 213 void set(int index,OopMap* value) { assert((index == 0) || ((index > 0) && (index < om_size())),"bad index"); _om_data[index] = value; } 214 215 public: 216 OopMapSet(); 217 218 // returns the number of OopMaps in this OopMapSet 219 int size() const { return _om_count; } 220 // returns the OopMap at a given index 221 OopMap* at(int index) const { assert((index >= 0) && (index <= om_count()),"bad index"); return _om_data[index]; } 222 223 // Collect OopMaps. 224 void add_gc_map(int pc, OopMap* map); 225 226 // Returns the only oop map. Used for reconstructing 227 // Adapter frames during deoptimization 228 OopMap* singular_oop_map(); 229 230 // returns OopMap in that is anchored to the pc 231 OopMap* find_map_at_offset(int pc_offset) const; 232 233 int heap_size() const; 234 235 // Methods oops_do() and all_do() filter out NULL oops and 236 // oop == Universe::narrow_oop_base() before passing oops 237 // to closures. 238 239 // Iterates through frame for a compiled method 240 static void oops_do (const frame* fr, 241 const RegisterMap* reg_map, OopClosure* f); 242 static void update_register_map(const frame* fr, RegisterMap *reg_map); 243 244 // Iterates through frame for a compiled method for dead ones and values, too 245 static void all_do(const frame* fr, const RegisterMap* reg_map, 246 OopClosure* oop_fn, 247 void derived_oop_fn(oop* base, oop* derived), 248 OopClosure* value_fn); 249 250 // Printing 251 void print_on(outputStream* st) const; 252 void print() const { print_on(tty); } 253 }; 254 255 class ImmutableOopMapBuilder; 256 257 class ImmutableOopMap { 258 friend class OopMapStream; 259 friend class VMStructs; 260 #ifdef ASSERT 261 friend class ImmutableOopMapBuilder; 262 #endif 263 private: 264 int _count; // contains the number of entries in this OopMap 265 266 address data_addr() const { return (address) this + sizeof(ImmutableOopMap); } 267 public: 268 ImmutableOopMap(const OopMap* oopmap); 269 270 bool has_derived_pointer() const PRODUCT_RETURN0; 271 int count() const { return _count; } 272 #ifdef ASSERT 273 int nr_of_bytes() const; // this is an expensive operation, only used in debug builds 274 #endif 275 276 // Printing 277 void print_on(outputStream* st) const; 278 void print() const { print_on(tty); } 279 }; 280 281 class ImmutableOopMapSet; 282 class ImmutableOopMap; 283 class OopMapSet; 284 285 class ImmutableOopMapPair { 286 friend class VMStructs; 287 private: 288 int _pc_offset; // program counter offset from the beginning of the method 289 int _oopmap_offset; // offset in the data in the ImmutableOopMapSet where the ImmutableOopMap is located 290 public: 291 ImmutableOopMapPair(int pc_offset, int oopmap_offset) : _pc_offset(pc_offset), _oopmap_offset(oopmap_offset) { 292 assert(pc_offset >= 0 && oopmap_offset >= 0, "check"); 293 } 294 const ImmutableOopMap* get_from(const ImmutableOopMapSet* set) const; 295 296 int pc_offset() const { return _pc_offset; } 297 int oopmap_offset() const { return _oopmap_offset; } 298 }; 299 300 class ImmutableOopMapSet { 301 friend class VMStructs; 302 private: 303 int _count; // nr of ImmutableOopMapPairs in the Set 304 int _size; // nr of bytes including ImmutableOopMapSet itself 305 306 address data() const { return (address) this + sizeof(*this) + sizeof(ImmutableOopMapPair) * _count; } 307 308 public: 309 ImmutableOopMapSet(const OopMapSet* oopmap_set, int size) : _count(oopmap_set->size()), _size(size) {} 310 311 ImmutableOopMap* oopmap_at_offset(int offset) const { 312 assert(offset >= 0 && offset < _size, "must be within boundaries"); 313 address addr = data() + offset; 314 return (ImmutableOopMap*) addr; 315 } 316 317 ImmutableOopMapPair* get_pairs() const { return (ImmutableOopMapPair*) ((address) this + sizeof(*this)); } 318 319 static ImmutableOopMapSet* build_from(const OopMapSet* oopmap_set); 320 321 const ImmutableOopMap* find_map_at_offset(int pc_offset) const; 322 323 const ImmutableOopMapPair* pair_at(int index) const { assert(index >= 0 && index < _count, "check"); return &get_pairs()[index]; } 324 325 int count() const { return _count; } 326 int nr_of_bytes() const { return _size; } 327 328 void print_on(outputStream* st) const; 329 void print() const { print_on(tty); } 330 }; 331 332 class OopMapStream : public StackObj { 333 private: 334 CompressedReadStream* _stream; 335 int _mask; 336 int _size; 337 int _position; 338 bool _valid_omv; 339 OopMapValue _omv; 340 void find_next(); 341 342 public: 343 OopMapStream(OopMap* oop_map, int oop_types_mask = OopMapValue::type_mask_in_place); 344 OopMapStream(const ImmutableOopMap* oop_map, int oop_types_mask = OopMapValue::type_mask_in_place); 345 bool is_done() { if(!_valid_omv) { find_next(); } return !_valid_omv; } 346 void next() { find_next(); } 347 OopMapValue current() { return _omv; } 348 #ifdef ASSERT 349 int stream_position() const { return _stream->position(); } 350 #endif 351 }; 352 353 354 // Derived pointer support. This table keeps track of all derived points on a 355 // stack. It is cleared before each scavenge/GC. During the traversal of all 356 // oops, it is filled in with references to all locations that contains a 357 // derived oop (assumed to be very few). When the GC is complete, the derived 358 // pointers are updated based on their base pointers new value and an offset. 359 #ifdef COMPILER2 360 class DerivedPointerTable : public AllStatic { 361 friend class VMStructs; 362 private: 363 static GrowableArray<DerivedPointerEntry*>* _list; 364 static bool _active; // do not record pointers for verify pass etc. 365 public: 366 static void clear(); // Called before scavenge/GC 367 static void add(oop *derived, oop *base); // Called during scavenge/GC 368 static void update_pointers(); // Called after scavenge/GC 369 static bool is_empty() { return _list == NULL || _list->is_empty(); } 370 static bool is_active() { return _active; } 371 static void set_active(bool value) { _active = value; } 372 }; 373 374 // A utility class to temporarily "deactivate" the DerivedPointerTable. 375 // (Note: clients are responsible for any MT-safety issues) 376 class DerivedPointerTableDeactivate: public StackObj { 377 private: 378 bool _active; 379 public: 380 DerivedPointerTableDeactivate() { 381 _active = DerivedPointerTable::is_active(); 382 if (_active) { 383 DerivedPointerTable::set_active(false); 384 } 385 } 386 387 ~DerivedPointerTableDeactivate() { 388 assert(!DerivedPointerTable::is_active(), 389 "Inconsistency: not MT-safe"); 390 if (_active) { 391 DerivedPointerTable::set_active(true); 392 } 393 } 394 }; 395 #endif // COMPILER2 396 397 #endif // SHARE_VM_COMPILER_OOPMAP_HPP