1 /* 2 * Copyright (c) 2018, 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 "asm/macroAssembler.inline.hpp" 27 #include "gc/g1/g1BarrierSet.hpp" 28 #include "gc/g1/g1BarrierSetAssembler.hpp" 29 #include "gc/g1/g1BarrierSetRuntime.hpp" 30 #include "gc/g1/g1CardTable.hpp" 31 #include "gc/g1/g1ThreadLocalData.hpp" 32 #include "gc/g1/heapRegion.hpp" 33 #include "interpreter/interp_masm.hpp" 34 #include "runtime/sharedRuntime.hpp" 35 #include "utilities/debug.hpp" 36 #include "utilities/macros.hpp" 37 #ifdef COMPILER1 38 #include "c1/c1_LIRAssembler.hpp" 39 #include "c1/c1_MacroAssembler.hpp" 40 #include "gc/g1/c1/g1BarrierSetC1.hpp" 41 #endif 42 43 #define __ masm-> 44 45 void G1BarrierSetAssembler::gen_write_ref_array_pre_barrier(MacroAssembler* masm, DecoratorSet decorators, 46 Register addr, Register count) { 47 bool dest_uninitialized = (decorators & IS_DEST_UNINITIALIZED) != 0; 48 49 if (!dest_uninitialized) { 50 Register thread = NOT_LP64(rax) LP64_ONLY(r15_thread); 51 #ifndef _LP64 52 __ push(thread); 53 __ get_thread(thread); 54 #endif 55 56 Label filtered; 57 Address in_progress(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_active_offset())); 58 // Is marking active? 59 if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) { 60 __ cmpl(in_progress, 0); 61 } else { 62 assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "Assumption"); 63 __ cmpb(in_progress, 0); 64 } 65 66 NOT_LP64(__ pop(thread);) 67 68 __ jcc(Assembler::equal, filtered); 69 70 __ push_call_clobbered_registers(false /* save_fpu */); 71 #ifdef _LP64 72 if (count == c_rarg0) { 73 if (addr == c_rarg1) { 74 // exactly backwards!! 75 __ xchgptr(c_rarg1, c_rarg0); 76 } else { 77 __ movptr(c_rarg1, count); 78 __ movptr(c_rarg0, addr); 79 } 80 } else { 81 __ movptr(c_rarg0, addr); 82 __ movptr(c_rarg1, count); 83 } 84 if (UseCompressedOops) { 85 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_array_pre_narrow_oop_entry), 2); 86 } else { 87 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_array_pre_oop_entry), 2); 88 } 89 #else 90 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_array_pre_oop_entry), 91 addr, count); 92 #endif 93 __ pop_call_clobbered_registers(false /* save_fpu */); 94 95 __ bind(filtered); 96 } 97 } 98 99 void G1BarrierSetAssembler::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators, 100 Register addr, Register count, Register tmp) { 101 __ push_call_clobbered_registers(false /* save_fpu */); 102 #ifdef _LP64 103 if (c_rarg0 == count) { // On win64 c_rarg0 == rcx 104 assert_different_registers(c_rarg1, addr); 105 __ mov(c_rarg1, count); 106 __ mov(c_rarg0, addr); 107 } else { 108 assert_different_registers(c_rarg0, count); 109 __ mov(c_rarg0, addr); 110 __ mov(c_rarg1, count); 111 } 112 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_array_post_entry), 2); 113 #else 114 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_array_post_entry), 115 addr, count); 116 #endif 117 __ pop_call_clobbered_registers(false /* save_fpu */); 118 } 119 120 void G1BarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 121 Register dst, Address src, Register tmp1, Register tmp_thread) { 122 bool on_oop = is_reference_type(type); 123 bool on_weak = (decorators & ON_WEAK_OOP_REF) != 0; 124 bool on_phantom = (decorators & ON_PHANTOM_OOP_REF) != 0; 125 bool on_reference = on_weak || on_phantom; 126 ModRefBarrierSetAssembler::load_at(masm, decorators, type, dst, src, tmp1, tmp_thread); 127 if (on_oop && on_reference) { 128 Register thread = NOT_LP64(tmp_thread) LP64_ONLY(r15_thread); 129 130 #ifndef _LP64 131 // Work around the x86_32 bug that only manifests with Loom for some reason. 132 // MacroAssembler::resolve_weak_handle calls this barrier with tmp_thread == noreg. 133 if (thread == noreg) { 134 if (dst != rcx && tmp1 != rcx) { 135 thread = rcx; 136 } else if (dst != rdx && tmp1 != rdx) { 137 thread = rdx; 138 } else if (dst != rdi && tmp1 != rdi) { 139 thread = rdi; 140 } 141 } 142 assert_different_registers(dst, tmp1, thread); 143 __ push(thread); 144 __ get_thread(thread); 145 #endif 146 147 // Generate the G1 pre-barrier code to log the value of 148 // the referent field in an SATB buffer. 149 g1_write_barrier_pre(masm /* masm */, 150 noreg /* obj */, 151 dst /* pre_val */, 152 thread /* thread */, 153 tmp1 /* tmp */, 154 true /* tosca_live */, 155 true /* expand_call */); 156 157 #ifndef _LP64 158 __ pop(thread); 159 #endif 160 } 161 } 162 163 void G1BarrierSetAssembler::g1_write_barrier_pre(MacroAssembler* masm, 164 Register obj, 165 Register pre_val, 166 Register thread, 167 Register tmp, 168 bool tosca_live, 169 bool expand_call) { 170 // If expand_call is true then we expand the call_VM_leaf macro 171 // directly to skip generating the check by 172 // InterpreterMacroAssembler::call_VM_leaf_base that checks _last_sp. 173 174 #ifdef _LP64 175 assert(thread == r15_thread, "must be"); 176 #endif // _LP64 177 178 Label done; 179 Label runtime; 180 181 assert(pre_val != noreg, "check this code"); 182 183 if (obj != noreg) { 184 assert_different_registers(obj, pre_val, tmp); 185 assert(pre_val != rax, "check this code"); 186 } 187 188 Address in_progress(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_active_offset())); 189 Address index(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_index_offset())); 190 Address buffer(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_buffer_offset())); 191 192 // Is marking active? 193 if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) { 194 __ cmpl(in_progress, 0); 195 } else { 196 assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "Assumption"); 197 __ cmpb(in_progress, 0); 198 } 199 __ jcc(Assembler::equal, done); 200 201 // Do we need to load the previous value? 202 if (obj != noreg) { 203 __ load_heap_oop(pre_val, Address(obj, 0), noreg, noreg, AS_RAW); 204 } 205 206 // Is the previous value null? 207 __ cmpptr(pre_val, NULL_WORD); 208 __ jcc(Assembler::equal, done); 209 210 // Can we store original value in the thread's buffer? 211 // Is index == 0? 212 // (The index field is typed as size_t.) 213 __ movptr(tmp, index); // tmp := *index_adr 214 __ cmpptr(tmp, 0); // tmp == 0? 215 __ jcc(Assembler::equal, runtime); // If yes, goto runtime 216 217 __ subptr(tmp, wordSize); // tmp := tmp - wordSize 218 __ movptr(index, tmp); // *index_adr := tmp 219 __ addptr(tmp, buffer); // tmp := tmp + *buffer_adr 220 221 // Record the previous value 222 __ movptr(Address(tmp, 0), pre_val); 223 __ jmp(done); 224 225 __ bind(runtime); 226 227 if (EnableValhalla && InlineTypePassFieldsAsArgs) { 228 // Barriers might be emitted when converting between (scalarized) calling conventions for inline 229 // types. Save all argument registers before calling into the runtime. 230 // TODO: use push_set() (see JDK-8283327 push/pop_call_clobbered_registers & aarch64 ) 231 __ pusha(); 232 __ subptr(rsp, 64); 233 __ movdbl(Address(rsp, 0), j_farg0); 234 __ movdbl(Address(rsp, 8), j_farg1); 235 __ movdbl(Address(rsp, 16), j_farg2); 236 __ movdbl(Address(rsp, 24), j_farg3); 237 __ movdbl(Address(rsp, 32), j_farg4); 238 __ movdbl(Address(rsp, 40), j_farg5); 239 __ movdbl(Address(rsp, 48), j_farg6); 240 __ movdbl(Address(rsp, 56), j_farg7); 241 } else { 242 // Determine and save the live input values 243 __ push_call_clobbered_registers(); 244 } 245 246 // Calling the runtime using the regular call_VM_leaf mechanism generates 247 // code (generated by InterpreterMacroAssember::call_VM_leaf_base) 248 // that checks that the *(ebp+frame::interpreter_frame_last_sp) == nullptr. 249 // 250 // If we care generating the pre-barrier without a frame (e.g. in the 251 // intrinsified Reference.get() routine) then ebp might be pointing to 252 // the caller frame and so this check will most likely fail at runtime. 253 // 254 // Expanding the call directly bypasses the generation of the check. 255 // So when we do not have have a full interpreter frame on the stack 256 // expand_call should be passed true. 257 258 if (expand_call) { 259 LP64_ONLY( assert(pre_val != c_rarg1, "smashed arg"); ) 260 #ifdef _LP64 261 if (c_rarg1 != thread) { 262 __ mov(c_rarg1, thread); 263 } 264 if (c_rarg0 != pre_val) { 265 __ mov(c_rarg0, pre_val); 266 } 267 #else 268 __ push(thread); 269 __ push(pre_val); 270 #endif 271 __ MacroAssembler::call_VM_leaf_base(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_pre_entry), 2); 272 } else { 273 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_pre_entry), pre_val, thread); 274 } 275 276 if (EnableValhalla && InlineTypePassFieldsAsArgs) { 277 // Restore registers 278 __ movdbl(j_farg0, Address(rsp, 0)); 279 __ movdbl(j_farg1, Address(rsp, 8)); 280 __ movdbl(j_farg2, Address(rsp, 16)); 281 __ movdbl(j_farg3, Address(rsp, 24)); 282 __ movdbl(j_farg4, Address(rsp, 32)); 283 __ movdbl(j_farg5, Address(rsp, 40)); 284 __ movdbl(j_farg6, Address(rsp, 48)); 285 __ movdbl(j_farg7, Address(rsp, 56)); 286 __ addptr(rsp, 64); 287 __ popa(); 288 } else { 289 __ pop_call_clobbered_registers(); 290 } 291 292 __ bind(done); 293 } 294 295 void G1BarrierSetAssembler::g1_write_barrier_post(MacroAssembler* masm, 296 Register store_addr, 297 Register new_val, 298 Register thread, 299 Register tmp, 300 Register tmp2) { 301 // Generated code assumes that buffer index is pointer sized. 302 STATIC_ASSERT(in_bytes(SATBMarkQueue::byte_width_of_index()) == sizeof(intptr_t)); 303 #ifdef _LP64 304 assert(thread == r15_thread, "must be"); 305 #endif // _LP64 306 307 Address queue_index(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_index_offset())); 308 Address buffer(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_buffer_offset())); 309 310 CardTableBarrierSet* ct = 311 barrier_set_cast<CardTableBarrierSet>(BarrierSet::barrier_set()); 312 313 Label done; 314 Label runtime; 315 316 // Does store cross heap regions? 317 318 __ movptr(tmp, store_addr); 319 __ xorptr(tmp, new_val); 320 __ shrptr(tmp, HeapRegion::LogOfHRGrainBytes); 321 __ jcc(Assembler::equal, done); 322 323 // crosses regions, storing null? 324 325 __ cmpptr(new_val, NULL_WORD); 326 __ jcc(Assembler::equal, done); 327 328 // storing region crossing non-null, is card already dirty? 329 330 const Register card_addr = tmp; 331 const Register cardtable = tmp2; 332 333 __ movptr(card_addr, store_addr); 334 __ shrptr(card_addr, CardTable::card_shift()); 335 // Do not use ExternalAddress to load 'byte_map_base', since 'byte_map_base' is NOT 336 // a valid address and therefore is not properly handled by the relocation code. 337 __ movptr(cardtable, (intptr_t)ct->card_table()->byte_map_base()); 338 __ addptr(card_addr, cardtable); 339 340 __ cmpb(Address(card_addr, 0), G1CardTable::g1_young_card_val()); 341 __ jcc(Assembler::equal, done); 342 343 __ membar(Assembler::Membar_mask_bits(Assembler::StoreLoad)); 344 __ cmpb(Address(card_addr, 0), G1CardTable::dirty_card_val()); 345 __ jcc(Assembler::equal, done); 346 347 348 // storing a region crossing, non-null oop, card is clean. 349 // dirty card and log. 350 351 __ movb(Address(card_addr, 0), G1CardTable::dirty_card_val()); 352 353 __ movptr(tmp2, queue_index); 354 __ testptr(tmp2, tmp2); 355 __ jcc(Assembler::zero, runtime); 356 __ subptr(tmp2, wordSize); 357 __ movptr(queue_index, tmp2); 358 __ addptr(tmp2, buffer); 359 __ movptr(Address(tmp2, 0), card_addr); 360 __ jmp(done); 361 362 __ bind(runtime); 363 // Barriers might be emitted when converting between (scalarized) calling conventions for inline 364 // types. Save all argument registers before calling into the runtime. 365 // TODO: use push_set() (see JDK-8283327 push/pop_call_clobbered_registers & aarch64) 366 __ pusha(); 367 __ subptr(rsp, 64); 368 __ movdbl(Address(rsp, 0), j_farg0); 369 __ movdbl(Address(rsp, 8), j_farg1); 370 __ movdbl(Address(rsp, 16), j_farg2); 371 __ movdbl(Address(rsp, 24), j_farg3); 372 __ movdbl(Address(rsp, 32), j_farg4); 373 __ movdbl(Address(rsp, 40), j_farg5); 374 __ movdbl(Address(rsp, 48), j_farg6); 375 __ movdbl(Address(rsp, 56), j_farg7); 376 377 #ifdef _LP64 378 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_post_entry), card_addr, r15_thread); 379 #else 380 __ push(thread); 381 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_post_entry), card_addr, thread); 382 __ pop(thread); 383 #endif 384 385 // Restore registers 386 __ movdbl(j_farg0, Address(rsp, 0)); 387 __ movdbl(j_farg1, Address(rsp, 8)); 388 __ movdbl(j_farg2, Address(rsp, 16)); 389 __ movdbl(j_farg3, Address(rsp, 24)); 390 __ movdbl(j_farg4, Address(rsp, 32)); 391 __ movdbl(j_farg5, Address(rsp, 40)); 392 __ movdbl(j_farg6, Address(rsp, 48)); 393 __ movdbl(j_farg7, Address(rsp, 56)); 394 __ addptr(rsp, 64); 395 __ popa(); 396 397 __ bind(done); 398 } 399 400 void G1BarrierSetAssembler::oop_store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 401 Address dst, Register val, Register tmp1, Register tmp2, Register tmp3) { 402 bool in_heap = (decorators & IN_HEAP) != 0; 403 bool as_normal = (decorators & AS_NORMAL) != 0; 404 bool dest_uninitialized = (decorators & IS_DEST_UNINITIALIZED) != 0; 405 406 bool needs_pre_barrier = as_normal && !dest_uninitialized; 407 bool needs_post_barrier = val != noreg && in_heap; 408 409 Register rthread = LP64_ONLY(r15_thread) NOT_LP64(rcx); 410 // flatten object address if needed 411 // We do it regardless of precise because we need the registers 412 if (dst.index() == noreg && dst.disp() == 0) { 413 if (dst.base() != tmp1) { 414 __ movptr(tmp1, dst.base()); 415 } 416 } else { 417 __ lea(tmp1, dst); 418 } 419 420 #ifndef _LP64 421 InterpreterMacroAssembler *imasm = static_cast<InterpreterMacroAssembler*>(masm); 422 #endif 423 424 NOT_LP64(__ get_thread(rcx)); 425 NOT_LP64(imasm->save_bcp()); 426 427 if (needs_pre_barrier) { 428 g1_write_barrier_pre(masm /*masm*/, 429 tmp1 /* obj */, 430 tmp2 /* pre_val */, 431 rthread /* thread */, 432 tmp3 /* tmp */, 433 val != noreg /* tosca_live */, 434 false /* expand_call */); 435 } 436 if (val == noreg) { 437 BarrierSetAssembler::store_at(masm, decorators, type, Address(tmp1, 0), val, noreg, noreg, noreg); 438 } else { 439 Register new_val = val; 440 if (needs_post_barrier) { 441 // G1 barrier needs uncompressed oop for region cross check. 442 if (UseCompressedOops) { 443 new_val = tmp2; 444 __ movptr(new_val, val); 445 } 446 } 447 BarrierSetAssembler::store_at(masm, decorators, type, Address(tmp1, 0), val, noreg, noreg, noreg); 448 if (needs_post_barrier) { 449 g1_write_barrier_post(masm /*masm*/, 450 tmp1 /* store_adr */, 451 new_val /* new_val */, 452 rthread /* thread */, 453 tmp3 /* tmp */, 454 tmp2 /* tmp2 */); 455 } 456 } 457 NOT_LP64(imasm->restore_bcp()); 458 } 459 460 #ifdef COMPILER1 461 462 #undef __ 463 #define __ ce->masm()-> 464 465 void G1BarrierSetAssembler::gen_pre_barrier_stub(LIR_Assembler* ce, G1PreBarrierStub* stub) { 466 G1BarrierSetC1* bs = (G1BarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1(); 467 // At this point we know that marking is in progress. 468 // If do_load() is true then we have to emit the 469 // load of the previous value; otherwise it has already 470 // been loaded into _pre_val. 471 472 __ bind(*stub->entry()); 473 assert(stub->pre_val()->is_register(), "Precondition."); 474 475 Register pre_val_reg = stub->pre_val()->as_register(); 476 477 if (stub->do_load()) { 478 ce->mem2reg(stub->addr(), stub->pre_val(), T_OBJECT, stub->patch_code(), stub->info(), false /*wide*/); 479 } 480 481 __ cmpptr(pre_val_reg, NULL_WORD); 482 __ jcc(Assembler::equal, *stub->continuation()); 483 ce->store_parameter(stub->pre_val()->as_register(), 0); 484 __ call(RuntimeAddress(bs->pre_barrier_c1_runtime_code_blob()->code_begin())); 485 __ jmp(*stub->continuation()); 486 487 } 488 489 void G1BarrierSetAssembler::gen_post_barrier_stub(LIR_Assembler* ce, G1PostBarrierStub* stub) { 490 G1BarrierSetC1* bs = (G1BarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1(); 491 __ bind(*stub->entry()); 492 assert(stub->addr()->is_register(), "Precondition."); 493 assert(stub->new_val()->is_register(), "Precondition."); 494 Register new_val_reg = stub->new_val()->as_register(); 495 __ cmpptr(new_val_reg, NULL_WORD); 496 __ jcc(Assembler::equal, *stub->continuation()); 497 ce->store_parameter(stub->addr()->as_pointer_register(), 0); 498 __ call(RuntimeAddress(bs->post_barrier_c1_runtime_code_blob()->code_begin())); 499 __ jmp(*stub->continuation()); 500 } 501 502 #undef __ 503 504 #define __ sasm-> 505 506 void G1BarrierSetAssembler::generate_c1_pre_barrier_runtime_stub(StubAssembler* sasm) { 507 // Generated code assumes that buffer index is pointer sized. 508 STATIC_ASSERT(in_bytes(SATBMarkQueue::byte_width_of_index()) == sizeof(intptr_t)); 509 510 __ prologue("g1_pre_barrier", false); 511 // arg0 : previous value of memory 512 513 __ push(rax); 514 __ push(rdx); 515 516 const Register pre_val = rax; 517 const Register thread = NOT_LP64(rax) LP64_ONLY(r15_thread); 518 const Register tmp = rdx; 519 520 NOT_LP64(__ get_thread(thread);) 521 522 Address queue_active(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_active_offset())); 523 Address queue_index(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_index_offset())); 524 Address buffer(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_buffer_offset())); 525 526 Label done; 527 Label runtime; 528 529 // Is marking still active? 530 if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) { 531 __ cmpl(queue_active, 0); 532 } else { 533 assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "Assumption"); 534 __ cmpb(queue_active, 0); 535 } 536 __ jcc(Assembler::equal, done); 537 538 // Can we store original value in the thread's buffer? 539 540 __ movptr(tmp, queue_index); 541 __ testptr(tmp, tmp); 542 __ jcc(Assembler::zero, runtime); 543 __ subptr(tmp, wordSize); 544 __ movptr(queue_index, tmp); 545 __ addptr(tmp, buffer); 546 547 // prev_val (rax) 548 __ load_parameter(0, pre_val); 549 __ movptr(Address(tmp, 0), pre_val); 550 __ jmp(done); 551 552 __ bind(runtime); 553 554 __ push_call_clobbered_registers(); 555 556 // load the pre-value 557 __ load_parameter(0, rcx); 558 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_pre_entry), rcx, thread); 559 560 __ pop_call_clobbered_registers(); 561 562 __ bind(done); 563 564 __ pop(rdx); 565 __ pop(rax); 566 567 __ epilogue(); 568 } 569 570 void G1BarrierSetAssembler::generate_c1_post_barrier_runtime_stub(StubAssembler* sasm) { 571 __ prologue("g1_post_barrier", false); 572 573 CardTableBarrierSet* ct = 574 barrier_set_cast<CardTableBarrierSet>(BarrierSet::barrier_set()); 575 576 Label done; 577 Label enqueued; 578 Label runtime; 579 580 // At this point we know new_value is non-null and the new_value crosses regions. 581 // Must check to see if card is already dirty 582 583 const Register thread = NOT_LP64(rax) LP64_ONLY(r15_thread); 584 585 Address queue_index(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_index_offset())); 586 Address buffer(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_buffer_offset())); 587 588 __ push(rax); 589 __ push(rcx); 590 591 const Register cardtable = rax; 592 const Register card_addr = rcx; 593 594 __ load_parameter(0, card_addr); 595 __ shrptr(card_addr, CardTable::card_shift()); 596 // Do not use ExternalAddress to load 'byte_map_base', since 'byte_map_base' is NOT 597 // a valid address and therefore is not properly handled by the relocation code. 598 __ movptr(cardtable, (intptr_t)ct->card_table()->byte_map_base()); 599 __ addptr(card_addr, cardtable); 600 601 NOT_LP64(__ get_thread(thread);) 602 603 __ cmpb(Address(card_addr, 0), G1CardTable::g1_young_card_val()); 604 __ jcc(Assembler::equal, done); 605 606 __ membar(Assembler::Membar_mask_bits(Assembler::StoreLoad)); 607 __ cmpb(Address(card_addr, 0), CardTable::dirty_card_val()); 608 __ jcc(Assembler::equal, done); 609 610 // storing region crossing non-null, card is clean. 611 // dirty card and log. 612 613 __ movb(Address(card_addr, 0), CardTable::dirty_card_val()); 614 615 const Register tmp = rdx; 616 __ push(rdx); 617 618 __ movptr(tmp, queue_index); 619 __ testptr(tmp, tmp); 620 __ jcc(Assembler::zero, runtime); 621 __ subptr(tmp, wordSize); 622 __ movptr(queue_index, tmp); 623 __ addptr(tmp, buffer); 624 __ movptr(Address(tmp, 0), card_addr); 625 __ jmp(enqueued); 626 627 __ bind(runtime); 628 __ push_call_clobbered_registers(); 629 630 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_post_entry), card_addr, thread); 631 632 __ pop_call_clobbered_registers(); 633 634 __ bind(enqueued); 635 __ pop(rdx); 636 637 __ bind(done); 638 __ pop(rcx); 639 __ pop(rax); 640 641 __ epilogue(); 642 } 643 644 #undef __ 645 646 #endif // COMPILER1