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/g1HeapRegion.hpp"
 32 #include "gc/g1/g1ThreadLocalData.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 
214   __ movptr(tmp, index);                   // tmp := *index_adr
215   __ cmpptr(tmp, 0);                       // tmp == 0?
216   __ jcc(Assembler::equal, runtime);       // If yes, goto runtime
217 
218   __ subptr(tmp, wordSize);                // tmp := tmp - wordSize
219   __ movptr(index, tmp);                   // *index_adr := tmp
220   __ addptr(tmp, buffer);                  // tmp := tmp + *buffer_adr
221 
222   // Record the previous value
223   __ movptr(Address(tmp, 0), pre_val);
224   __ jmp(done);
225 
226   __ bind(runtime);
227 
228   // Determine and save the live input values
229   __ push_call_clobbered_registers();
230 
231   // Calling the runtime using the regular call_VM_leaf mechanism generates
232   // code (generated by InterpreterMacroAssember::call_VM_leaf_base)
233   // that checks that the *(ebp+frame::interpreter_frame_last_sp) == nullptr.
234   //
235   // If we care generating the pre-barrier without a frame (e.g. in the
236   // intrinsified Reference.get() routine) then ebp might be pointing to
237   // the caller frame and so this check will most likely fail at runtime.
238   //
239   // Expanding the call directly bypasses the generation of the check.
240   // So when we do not have have a full interpreter frame on the stack
241   // expand_call should be passed true.
242 
243   if (expand_call) {
244     LP64_ONLY( assert(pre_val != c_rarg1, "smashed arg"); )
245 #ifdef _LP64
246     if (c_rarg1 != thread) {
247       __ mov(c_rarg1, thread);
248     }
249     if (c_rarg0 != pre_val) {
250       __ mov(c_rarg0, pre_val);
251     }
252 #else
253     __ push(thread);
254     __ push(pre_val);
255 #endif
256     __ MacroAssembler::call_VM_leaf_base(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_pre_entry), 2);
257   } else {
258     __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_pre_entry), pre_val, thread);
259   }
260 
261   __ pop_call_clobbered_registers();
262 
263   __ bind(done);
264 }
265 
266 void G1BarrierSetAssembler::g1_write_barrier_post(MacroAssembler* masm,
267                                                   Register store_addr,
268                                                   Register new_val,
269                                                   Register thread,
270                                                   Register tmp,
271                                                   Register tmp2) {
272 #ifdef _LP64
273   assert(thread == r15_thread, "must be");
274 #endif // _LP64
275 
276   Address queue_index(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_index_offset()));
277   Address buffer(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_buffer_offset()));
278 
279   CardTableBarrierSet* ct =
280     barrier_set_cast<CardTableBarrierSet>(BarrierSet::barrier_set());
281 
282   Label done;
283   Label runtime;
284 
285   // Does store cross heap regions?
286 
287   __ movptr(tmp, store_addr);
288   __ xorptr(tmp, new_val);
289   __ shrptr(tmp, HeapRegion::LogOfHRGrainBytes);
290   __ jcc(Assembler::equal, done);
291 
292   // crosses regions, storing null?
293 
294   __ cmpptr(new_val, NULL_WORD);
295   __ jcc(Assembler::equal, done);
296 
297   // storing region crossing non-null, is card already dirty?
298 
299   const Register card_addr = tmp;
300   const Register cardtable = tmp2;
301 
302   __ movptr(card_addr, store_addr);
303   __ shrptr(card_addr, CardTable::card_shift());
304   // Do not use ExternalAddress to load 'byte_map_base', since 'byte_map_base' is NOT
305   // a valid address and therefore is not properly handled by the relocation code.
306   __ movptr(cardtable, (intptr_t)ct->card_table()->byte_map_base());
307   __ addptr(card_addr, cardtable);
308 
309   __ cmpb(Address(card_addr, 0), G1CardTable::g1_young_card_val());
310   __ jcc(Assembler::equal, done);
311 
312   __ membar(Assembler::Membar_mask_bits(Assembler::StoreLoad));
313   __ cmpb(Address(card_addr, 0), G1CardTable::dirty_card_val());
314   __ jcc(Assembler::equal, done);
315 
316 
317   // storing a region crossing, non-null oop, card is clean.
318   // dirty card and log.
319 
320   __ movb(Address(card_addr, 0), G1CardTable::dirty_card_val());
321 
322   // The code below assumes that buffer index is pointer sized.
323   STATIC_ASSERT(in_bytes(G1DirtyCardQueue::byte_width_of_index()) == sizeof(intptr_t));
324 
325   __ movptr(tmp2, queue_index);
326   __ testptr(tmp2, tmp2);
327   __ jcc(Assembler::zero, runtime);
328   __ subptr(tmp2, wordSize);
329   __ movptr(queue_index, tmp2);
330   __ addptr(tmp2, buffer);
331   __ movptr(Address(tmp2, 0), card_addr);
332   __ jmp(done);
333 
334   __ bind(runtime);
335   // save the live input values
336   RegSet saved = RegSet::of(store_addr NOT_LP64(COMMA thread));
337   __ push_set(saved);
338   __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_post_entry), card_addr, thread);
339   __ pop_set(saved);
340 
341   __ bind(done);
342 }
343 
344 void G1BarrierSetAssembler::oop_store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
345                                          Address dst, Register val, Register tmp1, Register tmp2, Register tmp3) {
346   bool in_heap = (decorators & IN_HEAP) != 0;
347   bool as_normal = (decorators & AS_NORMAL) != 0;
348 
349   bool needs_pre_barrier = as_normal;
350   bool needs_post_barrier = val != noreg && in_heap;
351 
352   Register rthread = LP64_ONLY(r15_thread) NOT_LP64(rcx);
353   // flatten object address if needed
354   // We do it regardless of precise because we need the registers
355   if (dst.index() == noreg && dst.disp() == 0) {
356     if (dst.base() != tmp1) {
357       __ movptr(tmp1, dst.base());
358     }
359   } else {
360     __ lea(tmp1, dst);
361   }
362 
363 #ifndef _LP64
364   InterpreterMacroAssembler *imasm = static_cast<InterpreterMacroAssembler*>(masm);
365 #endif
366 
367   NOT_LP64(__ get_thread(rcx));
368   NOT_LP64(imasm->save_bcp());
369 
370   if (needs_pre_barrier) {
371     g1_write_barrier_pre(masm /*masm*/,
372                          tmp1 /* obj */,
373                          tmp2 /* pre_val */,
374                          rthread /* thread */,
375                          tmp3  /* tmp */,
376                          val != noreg /* tosca_live */,
377                          false /* expand_call */);
378   }
379   if (val == noreg) {
380     BarrierSetAssembler::store_at(masm, decorators, type, Address(tmp1, 0), val, noreg, noreg, noreg);
381   } else {
382     Register new_val = val;
383     if (needs_post_barrier) {
384       // G1 barrier needs uncompressed oop for region cross check.
385       if (UseCompressedOops) {
386         new_val = tmp2;
387         __ movptr(new_val, val);
388       }
389     }
390     BarrierSetAssembler::store_at(masm, decorators, type, Address(tmp1, 0), val, noreg, noreg, noreg);
391     if (needs_post_barrier) {
392       g1_write_barrier_post(masm /*masm*/,
393                             tmp1 /* store_adr */,
394                             new_val /* new_val */,
395                             rthread /* thread */,
396                             tmp3 /* tmp */,
397                             tmp2 /* tmp2 */);
398     }
399   }
400   NOT_LP64(imasm->restore_bcp());
401 }
402 
403 #ifdef COMPILER1
404 
405 #undef __
406 #define __ ce->masm()->
407 
408 void G1BarrierSetAssembler::gen_pre_barrier_stub(LIR_Assembler* ce, G1PreBarrierStub* stub) {
409   G1BarrierSetC1* bs = (G1BarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1();
410   // At this point we know that marking is in progress.
411   // If do_load() is true then we have to emit the
412   // load of the previous value; otherwise it has already
413   // been loaded into _pre_val.
414 
415   __ bind(*stub->entry());
416   assert(stub->pre_val()->is_register(), "Precondition.");
417 
418   Register pre_val_reg = stub->pre_val()->as_register();
419 
420   if (stub->do_load()) {
421     ce->mem2reg(stub->addr(), stub->pre_val(), T_OBJECT, stub->patch_code(), stub->info(), false /*wide*/);
422   }
423 
424   __ cmpptr(pre_val_reg, NULL_WORD);
425   __ jcc(Assembler::equal, *stub->continuation());
426   ce->store_parameter(stub->pre_val()->as_register(), 0);
427   __ call(RuntimeAddress(bs->pre_barrier_c1_runtime_code_blob()->code_begin()));
428   __ jmp(*stub->continuation());
429 
430 }
431 
432 void G1BarrierSetAssembler::gen_post_barrier_stub(LIR_Assembler* ce, G1PostBarrierStub* stub) {
433   G1BarrierSetC1* bs = (G1BarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1();
434   __ bind(*stub->entry());
435   assert(stub->addr()->is_register(), "Precondition.");
436   assert(stub->new_val()->is_register(), "Precondition.");
437   Register new_val_reg = stub->new_val()->as_register();
438   __ cmpptr(new_val_reg, NULL_WORD);
439   __ jcc(Assembler::equal, *stub->continuation());
440   ce->store_parameter(stub->addr()->as_pointer_register(), 0);
441   __ call(RuntimeAddress(bs->post_barrier_c1_runtime_code_blob()->code_begin()));
442   __ jmp(*stub->continuation());
443 }
444 
445 #undef __
446 
447 #define __ sasm->
448 
449 void G1BarrierSetAssembler::generate_c1_pre_barrier_runtime_stub(StubAssembler* sasm) {
450   // Generated code assumes that buffer index is pointer sized.
451   STATIC_ASSERT(in_bytes(SATBMarkQueue::byte_width_of_index()) == sizeof(intptr_t));
452 
453   __ prologue("g1_pre_barrier", false);
454   // arg0 : previous value of memory
455 
456   __ push(rax);
457   __ push(rdx);
458 
459   const Register pre_val = rax;
460   const Register thread = NOT_LP64(rax) LP64_ONLY(r15_thread);
461   const Register tmp = rdx;
462 
463   NOT_LP64(__ get_thread(thread);)
464 
465   Address queue_active(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_active_offset()));
466   Address queue_index(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_index_offset()));
467   Address buffer(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_buffer_offset()));
468 
469   Label done;
470   Label runtime;
471 
472   // Is marking still active?
473   if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) {
474     __ cmpl(queue_active, 0);
475   } else {
476     assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "Assumption");
477     __ cmpb(queue_active, 0);
478   }
479   __ jcc(Assembler::equal, done);
480 
481   // Can we store original value in the thread's buffer?
482 
483   __ movptr(tmp, queue_index);
484   __ testptr(tmp, tmp);
485   __ jcc(Assembler::zero, runtime);
486   __ subptr(tmp, wordSize);
487   __ movptr(queue_index, tmp);
488   __ addptr(tmp, buffer);
489 
490   // prev_val (rax)
491   __ load_parameter(0, pre_val);
492   __ movptr(Address(tmp, 0), pre_val);
493   __ jmp(done);
494 
495   __ bind(runtime);
496 
497   __ push_call_clobbered_registers();
498 
499   // load the pre-value
500   __ load_parameter(0, rcx);
501   __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_pre_entry), rcx, thread);
502 
503   __ pop_call_clobbered_registers();
504 
505   __ bind(done);
506 
507   __ pop(rdx);
508   __ pop(rax);
509 
510   __ epilogue();
511 }
512 
513 void G1BarrierSetAssembler::generate_c1_post_barrier_runtime_stub(StubAssembler* sasm) {
514   __ prologue("g1_post_barrier", false);
515 
516   CardTableBarrierSet* ct =
517     barrier_set_cast<CardTableBarrierSet>(BarrierSet::barrier_set());
518 
519   Label done;
520   Label enqueued;
521   Label runtime;
522 
523   // At this point we know new_value is non-null and the new_value crosses regions.
524   // Must check to see if card is already dirty
525 
526   const Register thread = NOT_LP64(rax) LP64_ONLY(r15_thread);
527 
528   Address queue_index(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_index_offset()));
529   Address buffer(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_buffer_offset()));
530 
531   __ push(rax);
532   __ push(rcx);
533 
534   const Register cardtable = rax;
535   const Register card_addr = rcx;
536 
537   __ load_parameter(0, card_addr);
538   __ shrptr(card_addr, CardTable::card_shift());
539   // Do not use ExternalAddress to load 'byte_map_base', since 'byte_map_base' is NOT
540   // a valid address and therefore is not properly handled by the relocation code.
541   __ movptr(cardtable, (intptr_t)ct->card_table()->byte_map_base());
542   __ addptr(card_addr, cardtable);
543 
544   NOT_LP64(__ get_thread(thread);)
545 
546   __ cmpb(Address(card_addr, 0), G1CardTable::g1_young_card_val());
547   __ jcc(Assembler::equal, done);
548 
549   __ membar(Assembler::Membar_mask_bits(Assembler::StoreLoad));
550   __ cmpb(Address(card_addr, 0), CardTable::dirty_card_val());
551   __ jcc(Assembler::equal, done);
552 
553   // storing region crossing non-null, card is clean.
554   // dirty card and log.
555 
556   __ movb(Address(card_addr, 0), CardTable::dirty_card_val());
557 
558   const Register tmp = rdx;
559   __ push(rdx);
560 
561   __ movptr(tmp, queue_index);
562   __ testptr(tmp, tmp);
563   __ jcc(Assembler::zero, runtime);
564   __ subptr(tmp, wordSize);
565   __ movptr(queue_index, tmp);
566   __ addptr(tmp, buffer);
567   __ movptr(Address(tmp, 0), card_addr);
568   __ jmp(enqueued);
569 
570   __ bind(runtime);
571   __ push_call_clobbered_registers();
572 
573   __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_post_entry), card_addr, thread);
574 
575   __ pop_call_clobbered_registers();
576 
577   __ bind(enqueued);
578   __ pop(rdx);
579 
580   __ bind(done);
581   __ pop(rcx);
582   __ pop(rax);
583 
584   __ epilogue();
585 }
586 
587 #undef __
588 
589 #endif // COMPILER1