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 "classfile/classLoaderData.hpp" 27 #include "gc/shared/barrierSet.hpp" 28 #include "gc/shared/barrierSetAssembler.hpp" 29 #include "gc/shared/barrierSetNMethod.hpp" 30 #include "gc/shared/collectedHeap.hpp" 31 #include "interpreter/interp_masm.hpp" 32 #include "memory/universe.hpp" 33 #include "runtime/javaThread.hpp" 34 #include "runtime/jniHandles.hpp" 35 #include "runtime/sharedRuntime.hpp" 36 #include "runtime/stubRoutines.hpp" 37 38 #define __ masm-> 39 40 void BarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 41 Register dst, Address src, Register tmp1, Register tmp_thread) { 42 bool in_heap = (decorators & IN_HEAP) != 0; 43 bool in_native = (decorators & IN_NATIVE) != 0; 44 bool is_not_null = (decorators & IS_NOT_NULL) != 0; 45 bool atomic = (decorators & MO_RELAXED) != 0; 46 47 switch (type) { 48 case T_OBJECT: 49 case T_ARRAY: { 50 if (in_heap) { 51 #ifdef _LP64 52 if (UseCompressedOops) { 53 __ movl(dst, src); 54 if (is_not_null) { 55 __ decode_heap_oop_not_null(dst); 56 } else { 57 __ decode_heap_oop(dst); 58 } 59 } else 60 #endif 61 { 62 __ movptr(dst, src); 63 } 64 } else { 65 assert(in_native, "why else?"); 66 __ movptr(dst, src); 67 } 68 break; 69 } 70 case T_BOOLEAN: __ load_unsigned_byte(dst, src); break; 71 case T_BYTE: __ load_signed_byte(dst, src); break; 72 case T_CHAR: __ load_unsigned_short(dst, src); break; 73 case T_SHORT: __ load_signed_short(dst, src); break; 74 case T_INT: __ movl (dst, src); break; 75 case T_ADDRESS: __ movptr(dst, src); break; 76 case T_FLOAT: 77 assert(dst == noreg, "only to ftos"); 78 __ load_float(src); 79 break; 80 case T_DOUBLE: 81 assert(dst == noreg, "only to dtos"); 82 __ load_double(src); 83 break; 84 case T_LONG: 85 assert(dst == noreg, "only to ltos"); 86 #ifdef _LP64 87 __ movq(rax, src); 88 #else 89 if (atomic) { 90 __ fild_d(src); // Must load atomically 91 __ subptr(rsp,2*wordSize); // Make space for store 92 __ fistp_d(Address(rsp,0)); 93 __ pop(rax); 94 __ pop(rdx); 95 } else { 96 __ movl(rax, src); 97 __ movl(rdx, src.plus_disp(wordSize)); 98 } 99 #endif 100 break; 101 default: Unimplemented(); 102 } 103 } 104 105 void BarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 106 Address dst, Register val, Register tmp1, Register tmp2, Register tmp3) { 107 bool in_heap = (decorators & IN_HEAP) != 0; 108 bool in_native = (decorators & IN_NATIVE) != 0; 109 bool is_not_null = (decorators & IS_NOT_NULL) != 0; 110 bool atomic = (decorators & MO_RELAXED) != 0; 111 112 switch (type) { 113 case T_OBJECT: 114 case T_ARRAY: { 115 if (in_heap) { 116 if (val == noreg) { 117 assert(!is_not_null, "inconsistent access"); 118 #ifdef _LP64 119 if (UseCompressedOops) { 120 __ movl(dst, NULL_WORD); 121 } else { 122 __ movslq(dst, NULL_WORD); 123 } 124 #else 125 __ movl(dst, NULL_WORD); 126 #endif 127 } else { 128 #ifdef _LP64 129 if (UseCompressedOops) { 130 assert(!dst.uses(val), "not enough registers"); 131 if (is_not_null) { 132 __ encode_heap_oop_not_null(val); 133 } else { 134 __ encode_heap_oop(val); 135 } 136 __ movl(dst, val); 137 } else 138 #endif 139 { 140 __ movptr(dst, val); 141 } 142 } 143 } else { 144 assert(in_native, "why else?"); 145 assert(val != noreg, "not supported"); 146 __ movptr(dst, val); 147 } 148 break; 149 } 150 case T_BOOLEAN: 151 __ andl(val, 0x1); // boolean is true if LSB is 1 152 __ movb(dst, val); 153 break; 154 case T_BYTE: 155 __ movb(dst, val); 156 break; 157 case T_SHORT: 158 __ movw(dst, val); 159 break; 160 case T_CHAR: 161 __ movw(dst, val); 162 break; 163 case T_INT: 164 __ movl(dst, val); 165 break; 166 case T_LONG: 167 assert(val == noreg, "only tos"); 168 #ifdef _LP64 169 __ movq(dst, rax); 170 #else 171 if (atomic) { 172 __ push(rdx); 173 __ push(rax); // Must update atomically with FIST 174 __ fild_d(Address(rsp,0)); // So load into FPU register 175 __ fistp_d(dst); // and put into memory atomically 176 __ addptr(rsp, 2*wordSize); 177 } else { 178 __ movptr(dst, rax); 179 __ movptr(dst.plus_disp(wordSize), rdx); 180 } 181 #endif 182 break; 183 case T_FLOAT: 184 assert(val == noreg, "only tos"); 185 __ store_float(dst); 186 break; 187 case T_DOUBLE: 188 assert(val == noreg, "only tos"); 189 __ store_double(dst); 190 break; 191 case T_ADDRESS: 192 __ movptr(dst, val); 193 break; 194 default: Unimplemented(); 195 } 196 } 197 198 void BarrierSetAssembler::copy_load_at(MacroAssembler* masm, 199 DecoratorSet decorators, 200 BasicType type, 201 size_t bytes, 202 Register dst, 203 Address src, 204 Register tmp) { 205 assert(bytes <= 8, "can only deal with non-vector registers"); 206 switch (bytes) { 207 case 1: 208 __ movb(dst, src); 209 break; 210 case 2: 211 __ movw(dst, src); 212 break; 213 case 4: 214 __ movl(dst, src); 215 break; 216 case 8: 217 #ifdef _LP64 218 __ movq(dst, src); 219 #else 220 fatal("No support for 8 bytes copy"); 221 #endif 222 break; 223 default: 224 fatal("Unexpected size"); 225 } 226 #ifdef _LP64 227 if ((decorators & ARRAYCOPY_CHECKCAST) != 0 && UseCompressedOops) { 228 __ decode_heap_oop(dst); 229 } 230 #endif 231 } 232 233 void BarrierSetAssembler::copy_store_at(MacroAssembler* masm, 234 DecoratorSet decorators, 235 BasicType type, 236 size_t bytes, 237 Address dst, 238 Register src, 239 Register tmp) { 240 #ifdef _LP64 241 if ((decorators & ARRAYCOPY_CHECKCAST) != 0 && UseCompressedOops) { 242 __ encode_heap_oop(src); 243 } 244 #endif 245 assert(bytes <= 8, "can only deal with non-vector registers"); 246 switch (bytes) { 247 case 1: 248 __ movb(dst, src); 249 break; 250 case 2: 251 __ movw(dst, src); 252 break; 253 case 4: 254 __ movl(dst, src); 255 break; 256 case 8: 257 #ifdef _LP64 258 __ movq(dst, src); 259 #else 260 fatal("No support for 8 bytes copy"); 261 #endif 262 break; 263 default: 264 fatal("Unexpected size"); 265 } 266 } 267 268 void BarrierSetAssembler::copy_load_at(MacroAssembler* masm, 269 DecoratorSet decorators, 270 BasicType type, 271 size_t bytes, 272 XMMRegister dst, 273 Address src, 274 Register tmp, 275 XMMRegister xmm_tmp) { 276 assert(bytes > 8, "can only deal with vector registers"); 277 if (bytes == 16) { 278 __ movdqu(dst, src); 279 } else if (bytes == 32) { 280 __ vmovdqu(dst, src); 281 } else { 282 fatal("No support for >32 bytes copy"); 283 } 284 } 285 286 void BarrierSetAssembler::copy_store_at(MacroAssembler* masm, 287 DecoratorSet decorators, 288 BasicType type, 289 size_t bytes, 290 Address dst, 291 XMMRegister src, 292 Register tmp1, 293 Register tmp2, 294 XMMRegister xmm_tmp) { 295 assert(bytes > 8, "can only deal with vector registers"); 296 if (bytes == 16) { 297 __ movdqu(dst, src); 298 } else if (bytes == 32) { 299 __ vmovdqu(dst, src); 300 } else { 301 fatal("No support for >32 bytes copy"); 302 } 303 } 304 305 void BarrierSetAssembler::try_resolve_jobject_in_native(MacroAssembler* masm, Register jni_env, 306 Register obj, Register tmp, Label& slowpath) { 307 __ clear_jobject_tag(obj); 308 __ movptr(obj, Address(obj, 0)); 309 } 310 311 void BarrierSetAssembler::tlab_allocate(MacroAssembler* masm, 312 Register thread, Register obj, 313 Register var_size_in_bytes, 314 int con_size_in_bytes, 315 Register t1, 316 Register t2, 317 Label& slow_case) { 318 assert_different_registers(obj, t1, t2); 319 assert_different_registers(obj, var_size_in_bytes, t1); 320 Register end = t2; 321 if (!thread->is_valid()) { 322 #ifdef _LP64 323 thread = r15_thread; 324 #else 325 assert(t1->is_valid(), "need temp reg"); 326 thread = t1; 327 __ get_thread(thread); 328 #endif 329 } 330 331 __ verify_tlab(); 332 333 __ movptr(obj, Address(thread, JavaThread::tlab_top_offset())); 334 if (var_size_in_bytes == noreg) { 335 __ lea(end, Address(obj, con_size_in_bytes)); 336 } else { 337 __ lea(end, Address(obj, var_size_in_bytes, Address::times_1)); 338 } 339 __ cmpptr(end, Address(thread, JavaThread::tlab_end_offset())); 340 __ jcc(Assembler::above, slow_case); 341 342 // update the tlab top pointer 343 __ movptr(Address(thread, JavaThread::tlab_top_offset()), end); 344 345 // recover var_size_in_bytes if necessary 346 if (var_size_in_bytes == end) { 347 __ subptr(var_size_in_bytes, obj); 348 } 349 __ verify_tlab(); 350 } 351 352 void BarrierSetAssembler::incr_allocated_bytes(MacroAssembler* masm, Register thread, 353 Register var_size_in_bytes, 354 int con_size_in_bytes, 355 Register t1) { 356 if (!thread->is_valid()) { 357 #ifdef _LP64 358 thread = r15_thread; 359 #else 360 assert(t1->is_valid(), "need temp reg"); 361 thread = t1; 362 __ get_thread(thread); 363 #endif 364 } 365 366 #ifdef _LP64 367 if (var_size_in_bytes->is_valid()) { 368 __ addq(Address(thread, in_bytes(JavaThread::allocated_bytes_offset())), var_size_in_bytes); 369 } else { 370 __ addq(Address(thread, in_bytes(JavaThread::allocated_bytes_offset())), con_size_in_bytes); 371 } 372 #else 373 if (var_size_in_bytes->is_valid()) { 374 __ addl(Address(thread, in_bytes(JavaThread::allocated_bytes_offset())), var_size_in_bytes); 375 } else { 376 __ addl(Address(thread, in_bytes(JavaThread::allocated_bytes_offset())), con_size_in_bytes); 377 } 378 __ adcl(Address(thread, in_bytes(JavaThread::allocated_bytes_offset())+4), 0); 379 #endif 380 } 381 382 #ifdef _LP64 383 void BarrierSetAssembler::nmethod_entry_barrier(MacroAssembler* masm, Label* slow_path, Label* continuation) { 384 BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod(); 385 if (bs_nm == nullptr) { 386 return; 387 } 388 Register thread = r15_thread; 389 Address disarmed_addr(thread, in_bytes(bs_nm->thread_disarmed_guard_value_offset())); 390 // The immediate is the last 4 bytes, so if we align the start of the cmp 391 // instruction to 4 bytes, we know that the second half of it is also 4 392 // byte aligned, which means that the immediate will not cross a cache line 393 __ align(4); 394 uintptr_t before_cmp = (uintptr_t)__ pc(); 395 __ cmpl_imm32(disarmed_addr, 0); 396 uintptr_t after_cmp = (uintptr_t)__ pc(); 397 guarantee(after_cmp - before_cmp == 8, "Wrong assumed instruction length"); 398 399 if (slow_path != nullptr) { 400 __ jcc(Assembler::notEqual, *slow_path); 401 __ bind(*continuation); 402 } else { 403 Label done; 404 __ jccb(Assembler::equal, done); 405 __ call(RuntimeAddress(StubRoutines::x86::method_entry_barrier())); 406 __ bind(done); 407 } 408 } 409 #else 410 void BarrierSetAssembler::nmethod_entry_barrier(MacroAssembler* masm, Label*, Label*) { 411 BarrierSetNMethod* bs_nm = BarrierSet::barrier_set()->barrier_set_nmethod(); 412 if (bs_nm == nullptr) { 413 return; 414 } 415 416 Label continuation; 417 418 Register tmp = rdi; 419 __ push(tmp); 420 __ movptr(tmp, (intptr_t)bs_nm->disarmed_guard_value_address()); 421 Address disarmed_addr(tmp, 0); 422 __ align(4); 423 __ cmpl_imm32(disarmed_addr, 0); 424 __ pop(tmp); 425 __ jcc(Assembler::equal, continuation); 426 __ call(RuntimeAddress(StubRoutines::x86::method_entry_barrier())); 427 __ bind(continuation); 428 } 429 #endif 430 431 void BarrierSetAssembler::c2i_entry_barrier(MacroAssembler* masm) { 432 BarrierSetNMethod* bs = BarrierSet::barrier_set()->barrier_set_nmethod(); 433 if (bs == nullptr) { 434 return; 435 } 436 437 Label bad_call; 438 __ cmpptr(rbx, 0); // rbx contains the incoming method for c2i adapters. 439 __ jcc(Assembler::equal, bad_call); 440 441 Register tmp1 = LP64_ONLY( rscratch1 ) NOT_LP64( rax ); 442 Register tmp2 = LP64_ONLY( rscratch2 ) NOT_LP64( rcx ); 443 #ifndef _LP64 444 __ push(tmp1); 445 __ push(tmp2); 446 #endif // !_LP64 447 448 // Pointer chase to the method holder to find out if the method is concurrently unloading. 449 Label method_live; 450 __ load_method_holder_cld(tmp1, rbx); 451 452 // Is it a strong CLD? 453 __ cmpl(Address(tmp1, ClassLoaderData::keep_alive_offset()), 0); 454 __ jcc(Assembler::greater, method_live); 455 456 // Is it a weak but alive CLD? 457 __ movptr(tmp1, Address(tmp1, ClassLoaderData::holder_offset())); 458 __ resolve_weak_handle(tmp1, tmp2); 459 __ cmpptr(tmp1, 0); 460 __ jcc(Assembler::notEqual, method_live); 461 462 #ifndef _LP64 463 __ pop(tmp2); 464 __ pop(tmp1); 465 #endif 466 467 __ bind(bad_call); 468 __ jump(RuntimeAddress(SharedRuntime::get_handle_wrong_method_stub())); 469 __ bind(method_live); 470 471 #ifndef _LP64 472 __ pop(tmp2); 473 __ pop(tmp1); 474 #endif 475 } 476 477 void BarrierSetAssembler::check_oop(MacroAssembler* masm, Register obj, Register tmp1, Register tmp2, Label& error) { 478 // Check if the oop is in the right area of memory 479 __ movptr(tmp1, obj); 480 __ movptr(tmp2, (intptr_t) Universe::verify_oop_mask()); 481 __ andptr(tmp1, tmp2); 482 __ movptr(tmp2, (intptr_t) Universe::verify_oop_bits()); 483 __ cmpptr(tmp1, tmp2); 484 __ jcc(Assembler::notZero, error); 485 486 // make sure klass is 'reasonable', which is not zero. 487 __ load_klass(obj, obj, tmp1); // get klass 488 __ testptr(obj, obj); 489 __ jcc(Assembler::zero, error); // if klass is null it is broken 490 }