1 /* 2 * Copyright (c) 2018, Red Hat, Inc. All rights reserved. 3 * 4 * This code is free software; you can redistribute it and/or modify it 5 * under the terms of the GNU General Public License version 2 only, as 6 * published by the Free Software Foundation. 7 * 8 * This code is distributed in the hope that it will be useful, but WITHOUT 9 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 10 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 11 * version 2 for more details (a copy is included in the LICENSE file that 12 * accompanied this code). 13 * 14 * You should have received a copy of the GNU General Public License version 15 * 2 along with this work; if not, write to the Free Software Foundation, 16 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 17 * 18 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 19 * or visit www.oracle.com if you need additional information or have any 20 * questions. 21 * 22 */ 23 24 #include "precompiled.hpp" 25 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp" 26 #include "gc/shenandoah/shenandoahForwarding.hpp" 27 #include "gc/shenandoah/shenandoahHeap.hpp" 28 #include "gc/shenandoah/shenandoahHeapRegion.hpp" 29 #include "gc/shenandoah/shenandoahHeuristics.hpp" 30 #include "gc/shenandoah/shenandoahRuntime.hpp" 31 #include "gc/shenandoah/shenandoahThreadLocalData.hpp" 32 #include "interpreter/interpreter.hpp" 33 #include "interpreter/interp_masm.hpp" 34 #include "runtime/sharedRuntime.hpp" 35 #include "runtime/thread.hpp" 36 #ifdef COMPILER1 37 #include "c1/c1_LIRAssembler.hpp" 38 #include "c1/c1_MacroAssembler.hpp" 39 #include "gc/shenandoah/c1/shenandoahBarrierSetC1.hpp" 40 #endif 41 42 #define __ masm-> 43 44 address ShenandoahBarrierSetAssembler::_shenandoah_lrb = NULL; 45 46 void ShenandoahBarrierSetAssembler::arraycopy_prologue(MacroAssembler* masm, DecoratorSet decorators, bool is_oop, 47 Register addr, Register count, RegSet saved_regs) { 48 if (is_oop) { 49 bool dest_uninitialized = (decorators & IS_DEST_UNINITIALIZED) != 0; 50 if (ShenandoahSATBBarrier && !dest_uninitialized && !ShenandoahHeap::heap()->heuristics()->can_do_traversal_gc()) { 51 52 Label done; 53 54 // Avoid calling runtime if count == 0 55 __ cbz(count, done); 56 57 // Is marking active? 58 Address gc_state(rthread, in_bytes(ShenandoahThreadLocalData::gc_state_offset())); 59 __ ldrb(rscratch1, gc_state); 60 __ tbz(rscratch1, ShenandoahHeap::MARKING_BITPOS, done); 61 62 __ push(saved_regs, sp); 63 if (count == c_rarg0) { 64 if (addr == c_rarg1) { 65 // exactly backwards!! 66 __ mov(rscratch1, c_rarg0); 67 __ mov(c_rarg0, c_rarg1); 68 __ mov(c_rarg1, rscratch1); 69 } else { 70 __ mov(c_rarg1, count); 71 __ mov(c_rarg0, addr); 72 } 73 } else { 74 __ mov(c_rarg0, addr); 75 __ mov(c_rarg1, count); 76 } 77 if (UseCompressedOops) { 78 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_pre_narrow_oop_entry), 2); 79 } else { 80 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_pre_oop_entry), 2); 81 } 82 __ pop(saved_regs, sp); 83 __ bind(done); 84 } 85 } 86 } 87 88 void ShenandoahBarrierSetAssembler::arraycopy_epilogue(MacroAssembler* masm, DecoratorSet decorators, bool is_oop, 89 Register start, Register count, Register scratch, RegSet saved_regs) { 90 if (is_oop) { 91 Label done; 92 93 // Avoid calling runtime if count == 0 94 __ cbz(count, done); 95 96 // Is updating references? 97 Address gc_state(rthread, in_bytes(ShenandoahThreadLocalData::gc_state_offset())); 98 __ ldrb(rscratch1, gc_state); 99 __ tbz(rscratch1, ShenandoahHeap::UPDATEREFS_BITPOS, done); 100 101 __ push(saved_regs, sp); 102 assert_different_registers(start, count, scratch); 103 assert_different_registers(c_rarg0, count); 104 __ mov(c_rarg0, start); 105 __ mov(c_rarg1, count); 106 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_post_entry), 2); 107 __ pop(saved_regs, sp); 108 109 __ bind(done); 110 } 111 } 112 113 void ShenandoahBarrierSetAssembler::shenandoah_write_barrier_pre(MacroAssembler* masm, 114 Register obj, 115 Register pre_val, 116 Register thread, 117 Register tmp, 118 bool tosca_live, 119 bool expand_call) { 120 if (ShenandoahSATBBarrier) { 121 satb_write_barrier_pre(masm, obj, pre_val, thread, tmp, tosca_live, expand_call); 122 } 123 } 124 125 void ShenandoahBarrierSetAssembler::satb_write_barrier_pre(MacroAssembler* masm, 126 Register obj, 127 Register pre_val, 128 Register thread, 129 Register tmp, 130 bool tosca_live, 131 bool expand_call) { 132 // If expand_call is true then we expand the call_VM_leaf macro 133 // directly to skip generating the check by 134 // InterpreterMacroAssembler::call_VM_leaf_base that checks _last_sp. 135 136 assert(thread == rthread, "must be"); 137 138 Label done; 139 Label runtime; 140 141 assert_different_registers(obj, pre_val, tmp, rscratch1); 142 assert(pre_val != noreg && tmp != noreg, "expecting a register"); 143 144 Address in_progress(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_active_offset())); 145 Address index(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset())); 146 Address buffer(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset())); 147 148 // Is marking active? 149 if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) { 150 __ ldrw(tmp, in_progress); 151 } else { 152 assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "Assumption"); 153 __ ldrb(tmp, in_progress); 154 } 155 __ cbzw(tmp, done); 156 157 // Do we need to load the previous value? 158 if (obj != noreg) { 159 __ load_heap_oop(pre_val, Address(obj, 0), noreg, noreg, AS_RAW); 160 } 161 162 // Is the previous value null? 163 __ cbz(pre_val, done); 164 165 // Can we store original value in the thread's buffer? 166 // Is index == 0? 167 // (The index field is typed as size_t.) 168 169 __ ldr(tmp, index); // tmp := *index_adr 170 __ cbz(tmp, runtime); // tmp == 0? 171 // If yes, goto runtime 172 173 __ sub(tmp, tmp, wordSize); // tmp := tmp - wordSize 174 __ str(tmp, index); // *index_adr := tmp 175 __ ldr(rscratch1, buffer); 176 __ add(tmp, tmp, rscratch1); // tmp := tmp + *buffer_adr 177 178 // Record the previous value 179 __ str(pre_val, Address(tmp, 0)); 180 __ b(done); 181 182 __ bind(runtime); 183 // save the live input values 184 RegSet saved = RegSet::of(pre_val); 185 if (tosca_live) saved += RegSet::of(r0); 186 if (obj != noreg) saved += RegSet::of(obj); 187 188 __ push(saved, sp); 189 190 // Calling the runtime using the regular call_VM_leaf mechanism generates 191 // code (generated by InterpreterMacroAssember::call_VM_leaf_base) 192 // that checks that the *(rfp+frame::interpreter_frame_last_sp) == NULL. 193 // 194 // If we care generating the pre-barrier without a frame (e.g. in the 195 // intrinsified Reference.get() routine) then ebp might be pointing to 196 // the caller frame and so this check will most likely fail at runtime. 197 // 198 // Expanding the call directly bypasses the generation of the check. 199 // So when we do not have have a full interpreter frame on the stack 200 // expand_call should be passed true. 201 202 if (expand_call) { 203 assert(pre_val != c_rarg1, "smashed arg"); 204 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), pre_val, thread); 205 } else { 206 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), pre_val, thread); 207 } 208 209 __ pop(saved, sp); 210 211 __ bind(done); 212 } 213 214 void ShenandoahBarrierSetAssembler::resolve_forward_pointer(MacroAssembler* masm, Register dst) { 215 assert(ShenandoahLoadRefBarrier || ShenandoahCASBarrier, "Should be enabled"); 216 Label is_null; 217 __ cbz(dst, is_null); 218 resolve_forward_pointer_not_null(masm, dst); 219 __ bind(is_null); 220 } 221 222 // IMPORTANT: This must preserve all registers, even rscratch1 and rscratch2. 223 void ShenandoahBarrierSetAssembler::resolve_forward_pointer_not_null(MacroAssembler* masm, Register dst) { 224 assert(ShenandoahLoadRefBarrier || ShenandoahCASBarrier, "Should be enabled"); 225 __ ldr(dst, Address(dst, ShenandoahForwarding::byte_offset())); 226 } 227 228 void ShenandoahBarrierSetAssembler::load_reference_barrier_not_null(MacroAssembler* masm, Register dst, Register tmp) { 229 assert(ShenandoahLoadRefBarrier, "Should be enabled"); 230 assert(dst != rscratch2, "need rscratch2"); 231 232 Label done; 233 __ enter(); 234 Address gc_state(rthread, in_bytes(ShenandoahThreadLocalData::gc_state_offset())); 235 __ ldrb(rscratch2, gc_state); 236 237 // Check for heap stability 238 __ tbz(rscratch2, ShenandoahHeap::HAS_FORWARDED_BITPOS, done); 239 240 RegSet to_save = RegSet::of(r0); 241 if (dst != r0) { 242 __ push(to_save, sp); 243 __ mov(r0, dst); 244 } 245 246 __ far_call(RuntimeAddress(CAST_FROM_FN_PTR(address, ShenandoahBarrierSetAssembler::shenandoah_lrb()))); 247 248 if (dst != r0) { 249 __ mov(dst, r0); 250 __ pop(to_save, sp); 251 } 252 253 __ bind(done); 254 __ leave(); 255 } 256 257 void ShenandoahBarrierSetAssembler::storeval_barrier(MacroAssembler* masm, Register dst, Register tmp) { 258 if (ShenandoahStoreValEnqueueBarrier) { 259 // Save possibly live regs. 260 RegSet live_regs = RegSet::range(r0, r4) - dst; 261 __ push(live_regs, sp); 262 __ strd(v0, __ pre(sp, 2 * -wordSize)); 263 264 satb_write_barrier_pre(masm, noreg, dst, rthread, tmp, true, false); 265 266 // Restore possibly live regs. 267 __ ldrd(v0, __ post(sp, 2 * wordSize)); 268 __ pop(live_regs, sp); 269 } 270 } 271 272 void ShenandoahBarrierSetAssembler::load_reference_barrier(MacroAssembler* masm, Register dst, Register tmp) { 273 if (ShenandoahLoadRefBarrier) { 274 Label is_null; 275 __ cbz(dst, is_null); 276 load_reference_barrier_not_null(masm, dst, tmp); 277 __ bind(is_null); 278 } 279 } 280 281 void ShenandoahBarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 282 Register dst, Address src, Register tmp1, Register tmp_thread) { 283 bool on_oop = type == T_OBJECT || type == T_ARRAY; 284 bool on_weak = (decorators & ON_WEAK_OOP_REF) != 0; 285 bool on_phantom = (decorators & ON_PHANTOM_OOP_REF) != 0; 286 bool on_reference = on_weak || on_phantom; 287 288 BarrierSetAssembler::load_at(masm, decorators, type, dst, src, tmp1, tmp_thread); 289 if (on_oop) { 290 load_reference_barrier(masm, dst, tmp1); 291 292 if (ShenandoahKeepAliveBarrier && on_reference) { 293 __ enter(); 294 satb_write_barrier_pre(masm /* masm */, 295 noreg /* obj */, 296 dst /* pre_val */, 297 rthread /* thread */, 298 tmp1 /* tmp */, 299 true /* tosca_live */, 300 true /* expand_call */); 301 __ leave(); 302 } 303 } 304 } 305 306 void ShenandoahBarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type, 307 Address dst, Register val, Register tmp1, Register tmp2) { 308 bool on_oop = type == T_OBJECT || type == T_ARRAY; 309 if (!on_oop) { 310 BarrierSetAssembler::store_at(masm, decorators, type, dst, val, tmp1, tmp2); 311 return; 312 } 313 314 // flatten object address if needed 315 if (dst.index() == noreg && dst.offset() == 0) { 316 if (dst.base() != r3) { 317 __ mov(r3, dst.base()); 318 } 319 } else { 320 __ lea(r3, dst); 321 } 322 323 shenandoah_write_barrier_pre(masm, 324 r3 /* obj */, 325 tmp2 /* pre_val */, 326 rthread /* thread */, 327 tmp1 /* tmp */, 328 val != noreg /* tosca_live */, 329 false /* expand_call */); 330 331 if (val == noreg) { 332 BarrierSetAssembler::store_at(masm, decorators, type, Address(r3, 0), noreg, noreg, noreg); 333 } else { 334 storeval_barrier(masm, val, tmp1); 335 // G1 barrier needs uncompressed oop for region cross check. 336 Register new_val = val; 337 if (UseCompressedOops) { 338 new_val = rscratch2; 339 __ mov(new_val, val); 340 } 341 BarrierSetAssembler::store_at(masm, decorators, type, Address(r3, 0), val, noreg, noreg); 342 } 343 344 } 345 346 void ShenandoahBarrierSetAssembler::tlab_allocate(MacroAssembler* masm, Register obj, 347 Register var_size_in_bytes, 348 int con_size_in_bytes, 349 Register t1, 350 Register t2, 351 Label& slow_case) { 352 353 assert_different_registers(obj, t2); 354 assert_different_registers(obj, var_size_in_bytes); 355 Register end = t2; 356 357 __ ldr(obj, Address(rthread, JavaThread::tlab_top_offset())); 358 if (var_size_in_bytes == noreg) { 359 __ lea(end, Address(obj, (int) (con_size_in_bytes + ShenandoahForwarding::byte_size()))); 360 } else { 361 __ add(var_size_in_bytes, var_size_in_bytes, ShenandoahForwarding::byte_size()); 362 __ lea(end, Address(obj, var_size_in_bytes)); 363 } 364 __ ldr(rscratch1, Address(rthread, JavaThread::tlab_end_offset())); 365 __ cmp(end, rscratch1); 366 __ br(Assembler::HI, slow_case); 367 368 // update the tlab top pointer 369 __ str(end, Address(rthread, JavaThread::tlab_top_offset())); 370 371 __ add(obj, obj, ShenandoahForwarding::byte_size()); 372 __ str(obj, Address(obj, ShenandoahForwarding::byte_offset())); 373 374 // recover var_size_in_bytes if necessary 375 if (var_size_in_bytes == end) { 376 __ sub(var_size_in_bytes, var_size_in_bytes, obj); 377 } 378 } 379 380 void ShenandoahBarrierSetAssembler::cmpxchg_oop(MacroAssembler* masm, Register addr, Register expected, Register new_val, 381 bool acquire, bool release, bool weak, bool is_cae, 382 Register result) { 383 Register tmp1 = rscratch1; 384 Register tmp2 = rscratch2; 385 bool is_narrow = UseCompressedOops; 386 Assembler::operand_size size = is_narrow ? Assembler::word : Assembler::xword; 387 388 assert_different_registers(addr, expected, new_val, tmp1, tmp2); 389 390 Label retry, done, fail; 391 392 // CAS, using LL/SC pair. 393 __ bind(retry); 394 __ load_exclusive(tmp1, addr, size, acquire); 395 if (is_narrow) { 396 __ cmpw(tmp1, expected); 397 } else { 398 __ cmp(tmp1, expected); 399 } 400 __ br(Assembler::NE, fail); 401 __ store_exclusive(tmp2, new_val, addr, size, release); 402 if (weak) { 403 __ cmpw(tmp2, 0u); // If the store fails, return NE to our caller 404 } else { 405 __ cbnzw(tmp2, retry); 406 } 407 __ b(done); 408 409 __ bind(fail); 410 // Check if rb(expected)==rb(tmp1) 411 // Shuffle registers so that we have memory value ready for next expected. 412 __ mov(tmp2, expected); 413 __ mov(expected, tmp1); 414 if (is_narrow) { 415 __ decode_heap_oop(tmp1, tmp1); 416 __ decode_heap_oop(tmp2, tmp2); 417 } 418 resolve_forward_pointer(masm, tmp1); 419 resolve_forward_pointer(masm, tmp2); 420 __ cmp(tmp1, tmp2); 421 // Retry with expected now being the value we just loaded from addr. 422 __ br(Assembler::EQ, retry); 423 if (is_cae && is_narrow) { 424 // For cmp-and-exchange and narrow oops, we need to restore 425 // the compressed old-value. We moved it to 'expected' a few lines up. 426 __ mov(tmp1, expected); 427 } 428 __ bind(done); 429 430 if (is_cae) { 431 __ mov(result, tmp1); 432 } else { 433 __ cset(result, Assembler::EQ); 434 } 435 } 436 437 #ifdef COMPILER1 438 439 #undef __ 440 #define __ ce->masm()-> 441 442 void ShenandoahBarrierSetAssembler::gen_pre_barrier_stub(LIR_Assembler* ce, ShenandoahPreBarrierStub* stub) { 443 ShenandoahBarrierSetC1* bs = (ShenandoahBarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1(); 444 // At this point we know that marking is in progress. 445 // If do_load() is true then we have to emit the 446 // load of the previous value; otherwise it has already 447 // been loaded into _pre_val. 448 449 __ bind(*stub->entry()); 450 451 assert(stub->pre_val()->is_register(), "Precondition."); 452 453 Register pre_val_reg = stub->pre_val()->as_register(); 454 455 if (stub->do_load()) { 456 ce->mem2reg(stub->addr(), stub->pre_val(), T_OBJECT, stub->patch_code(), stub->info(), false /*wide*/, false /*unaligned*/); 457 } 458 __ cbz(pre_val_reg, *stub->continuation()); 459 ce->store_parameter(stub->pre_val()->as_register(), 0); 460 __ far_call(RuntimeAddress(bs->pre_barrier_c1_runtime_code_blob()->code_begin())); 461 __ b(*stub->continuation()); 462 } 463 464 void ShenandoahBarrierSetAssembler::gen_load_reference_barrier_stub(LIR_Assembler* ce, ShenandoahLoadReferenceBarrierStub* stub) { 465 466 Register obj = stub->obj()->as_register(); 467 Register res = stub->result()->as_register(); 468 469 Label done; 470 471 __ bind(*stub->entry()); 472 473 if (res != obj) { 474 __ mov(res, obj); 475 } 476 // Check for null. 477 if (stub->needs_null_check()) { 478 __ cbz(res, done); 479 } 480 481 load_reference_barrier_not_null(ce->masm(), res, rscratch1); 482 483 __ bind(done); 484 __ b(*stub->continuation()); 485 } 486 487 #undef __ 488 489 #define __ sasm-> 490 491 void ShenandoahBarrierSetAssembler::generate_c1_pre_barrier_runtime_stub(StubAssembler* sasm) { 492 __ prologue("shenandoah_pre_barrier", false); 493 494 // arg0 : previous value of memory 495 496 BarrierSet* bs = BarrierSet::barrier_set(); 497 498 const Register pre_val = r0; 499 const Register thread = rthread; 500 const Register tmp = rscratch1; 501 502 Address queue_index(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset())); 503 Address buffer(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset())); 504 505 Label done; 506 Label runtime; 507 508 // Is marking still active? 509 Address gc_state(thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset())); 510 __ ldrb(tmp, gc_state); 511 __ mov(rscratch2, ShenandoahHeap::MARKING | ShenandoahHeap::TRAVERSAL); 512 __ tst(tmp, rscratch2); 513 __ br(Assembler::EQ, done); 514 515 // Can we store original value in the thread's buffer? 516 __ ldr(tmp, queue_index); 517 __ cbz(tmp, runtime); 518 519 __ sub(tmp, tmp, wordSize); 520 __ str(tmp, queue_index); 521 __ ldr(rscratch2, buffer); 522 __ add(tmp, tmp, rscratch2); 523 __ load_parameter(0, rscratch2); 524 __ str(rscratch2, Address(tmp, 0)); 525 __ b(done); 526 527 __ bind(runtime); 528 __ push_call_clobbered_registers(); 529 __ load_parameter(0, pre_val); 530 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), pre_val, thread); 531 __ pop_call_clobbered_registers(); 532 __ bind(done); 533 534 __ epilogue(); 535 } 536 537 #undef __ 538 539 #endif // COMPILER1 540 541 address ShenandoahBarrierSetAssembler::shenandoah_lrb() { 542 assert(_shenandoah_lrb != NULL, "need load reference barrier stub"); 543 return _shenandoah_lrb; 544 } 545 546 #define __ cgen->assembler()-> 547 548 // Shenandoah load reference barrier. 549 // 550 // Input: 551 // r0: OOP to evacuate. Not null. 552 // 553 // Output: 554 // r0: Pointer to evacuated OOP. 555 // 556 // Trash rscratch1, rscratch2. Preserve everything else. 557 address ShenandoahBarrierSetAssembler::generate_shenandoah_lrb(StubCodeGenerator* cgen) { 558 559 __ align(6); 560 StubCodeMark mark(cgen, "StubRoutines", "shenandoah_lrb"); 561 address start = __ pc(); 562 563 Label work, done; 564 __ mov(rscratch2, ShenandoahHeap::in_cset_fast_test_addr()); 565 __ lsr(rscratch1, r0, ShenandoahHeapRegion::region_size_bytes_shift_jint()); 566 __ ldrb(rscratch2, Address(rscratch2, rscratch1)); 567 __ tbnz(rscratch2, 0, work); 568 __ ret(lr); 569 __ bind(work); 570 571 __ mov(rscratch2, r0); 572 resolve_forward_pointer_not_null(cgen->assembler(), r0); 573 __ cmp(rscratch2, r0); 574 __ br(Assembler::NE, done); 575 576 __ enter(); // required for proper stackwalking of RuntimeStub frame 577 578 __ push_call_clobbered_registers(); 579 580 __ mov(lr, CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_JRT)); 581 __ blrt(lr, 1, 0, MacroAssembler::ret_type_integral); 582 __ mov(rscratch1, r0); 583 __ pop_call_clobbered_registers(); 584 __ mov(r0, rscratch1); 585 586 __ leave(); // required for proper stackwalking of RuntimeStub frame 587 __ bind(done); 588 __ ret(lr); 589 590 return start; 591 } 592 593 #undef __ 594 595 void ShenandoahBarrierSetAssembler::barrier_stubs_init() { 596 if (ShenandoahLoadRefBarrier) { 597 int stub_code_size = 2048; 598 ResourceMark rm; 599 BufferBlob* bb = BufferBlob::create("shenandoah_barrier_stubs", stub_code_size); 600 CodeBuffer buf(bb); 601 StubCodeGenerator cgen(&buf); 602 _shenandoah_lrb = generate_shenandoah_lrb(&cgen); 603 } 604 }