1 /*
2 * Copyright (c) 2018, Red Hat, Inc. and/or its affiliates.
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/brooksPointer.hpp"
26 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp"
27 #include "gc/shenandoah/shenandoahConnectionMatrix.hpp"
28 #include "gc/shenandoah/shenandoahHeap.hpp"
29 #include "gc/shenandoah/shenandoahHeapRegion.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_wb = NULL;
45 address ShenandoahBarrierSetAssembler::_shenandoah_wb_C = NULL;
46
47 void ShenandoahBarrierSetAssembler::arraycopy_prologue(MacroAssembler* masm, DecoratorSet decorators, bool is_oop,
48 Register addr, Register count, RegSet saved_regs) {
49 if (is_oop) {
50 bool dest_uninitialized = (decorators & AS_DEST_NOT_INITIALIZED) != 0;
51 if (!dest_uninitialized) {
52 __ push(saved_regs, sp);
53 if (count == c_rarg0) {
54 if (addr == c_rarg1) {
55 // exactly backwards!!
56 __ mov(rscratch1, c_rarg0);
57 __ mov(c_rarg0, c_rarg1);
58 __ mov(c_rarg1, rscratch1);
59 } else {
60 __ mov(c_rarg1, count);
61 __ mov(c_rarg0, addr);
62 }
63 } else {
64 __ mov(c_rarg0, addr);
65 __ mov(c_rarg1, count);
66 }
67 if (UseCompressedOops) {
68 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_pre_narrow_oop_entry), 2);
69 } else {
70 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_pre_oop_entry), 2);
71 }
72 __ pop(saved_regs, sp);
73 }
74 }
75 }
76
77 void ShenandoahBarrierSetAssembler::arraycopy_epilogue(MacroAssembler* masm, DecoratorSet decorators, bool is_oop,
78 Register start, Register end, Register scratch, RegSet saved_regs) {
79 if (is_oop) {
80 __ push(saved_regs, sp);
81 // must compute element count unless barrier set interface is changed (other platforms supply count)
82 assert_different_registers(start, end, scratch);
83 __ lea(scratch, Address(end, BytesPerHeapOop));
84 __ sub(scratch, scratch, start); // subtract start to get #bytes
85 __ lsr(scratch, scratch, LogBytesPerHeapOop); // convert to element count
86 __ mov(c_rarg0, start);
87 __ mov(c_rarg1, scratch);
88 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_post_entry), 2);
89 __ pop(saved_regs, sp);
90 }
91 }
92
93 void ShenandoahBarrierSetAssembler::shenandoah_write_barrier_pre(MacroAssembler* masm,
94 Register obj,
95 Register pre_val,
96 Register thread,
97 Register tmp,
98 bool tosca_live,
99 bool expand_call) {
100 if (ShenandoahSATBBarrier) {
101 satb_write_barrier_pre(masm, obj, pre_val, thread, tmp, tosca_live, expand_call);
102 }
103 }
104
105 void ShenandoahBarrierSetAssembler::satb_write_barrier_pre(MacroAssembler* masm,
106 Register obj,
107 Register pre_val,
108 Register thread,
109 Register tmp,
110 bool tosca_live,
111 bool expand_call) {
112 // If expand_call is true then we expand the call_VM_leaf macro
113 // directly to skip generating the check by
114 // InterpreterMacroAssembler::call_VM_leaf_base that checks _last_sp.
115
116 assert(thread == rthread, "must be");
117
118 Label done;
119 Label runtime;
120
121 assert_different_registers(obj, pre_val, tmp, rscratch1);
122 assert(pre_val != noreg && tmp != noreg, "expecting a register");
123
124 Address in_progress(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_active_offset()));
125 Address index(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset()));
126 Address buffer(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()));
127
128 // Is marking active?
129 if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) {
130 __ ldrw(tmp, in_progress);
131 } else {
132 assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "Assumption");
133 __ ldrb(tmp, in_progress);
134 }
135 __ cbzw(tmp, done);
136
137 // Do we need to load the previous value?
138 if (obj != noreg) {
139 __ load_heap_oop(pre_val, Address(obj, 0), noreg, noreg, AS_RAW);
140 }
141
142 // Is the previous value null?
143 __ cbz(pre_val, done);
144
145 // Can we store original value in the thread's buffer?
146 // Is index == 0?
147 // (The index field is typed as size_t.)
148
149 __ ldr(tmp, index); // tmp := *index_adr
150 __ cbz(tmp, runtime); // tmp == 0?
151 // If yes, goto runtime
152
153 __ sub(tmp, tmp, wordSize); // tmp := tmp - wordSize
154 __ str(tmp, index); // *index_adr := tmp
155 __ ldr(rscratch1, buffer);
156 __ add(tmp, tmp, rscratch1); // tmp := tmp + *buffer_adr
157
158 // Record the previous value
159 __ str(pre_val, Address(tmp, 0));
160 __ b(done);
161
162 __ bind(runtime);
163 // save the live input values
164 RegSet saved = RegSet::of(pre_val);
165 if (tosca_live) saved += RegSet::of(r0);
166 if (obj != noreg) saved += RegSet::of(obj);
167
168 __ push(saved, sp);
169
170 // Calling the runtime using the regular call_VM_leaf mechanism generates
171 // code (generated by InterpreterMacroAssember::call_VM_leaf_base)
172 // that checks that the *(rfp+frame::interpreter_frame_last_sp) == NULL.
173 //
174 // If we care generating the pre-barrier without a frame (e.g. in the
175 // intrinsified Reference.get() routine) then ebp might be pointing to
176 // the caller frame and so this check will most likely fail at runtime.
177 //
178 // Expanding the call directly bypasses the generation of the check.
179 // So when we do not have have a full interpreter frame on the stack
180 // expand_call should be passed true.
181
182 if (expand_call) {
183 assert(pre_val != c_rarg1, "smashed arg");
184 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), pre_val, thread);
185 } else {
186 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), pre_val, thread);
187 }
188
189 __ pop(saved, sp);
190
191 __ bind(done);
192 }
193
194 void ShenandoahBarrierSetAssembler::shenandoah_write_barrier_post(MacroAssembler* masm,
195 Register store_addr,
196 Register new_val,
197 Register thread,
198 Register tmp,
199 Register tmp2) {
200 assert(thread == rthread, "must be");
201 assert(UseShenandoahGC, "expect Shenandoah GC");
202
203 if (! UseShenandoahMatrix) {
204 // No need for that barrier if not using matrix.
205 return;
206 }
207
208 assert_different_registers(store_addr, new_val, thread, tmp, tmp2, rscratch1);
209
210 Label done;
211 __ cbz(new_val, done);
212
213 ShenandoahConnectionMatrix* matrix = ShenandoahHeap::heap()->connection_matrix();
214
215 // Compute to-region index
216 __ lsr(tmp, new_val, ShenandoahHeapRegion::region_size_bytes_shift_jint());
217
218 // Compute from-region index
219 __ lsr(tmp2, store_addr, ShenandoahHeapRegion::region_size_bytes_shift_jint());
220
221 // Compute matrix index
222 __ mov(rscratch1, matrix->stride_jint());
223 // Address is _matrix[to * stride + from]
224 __ madd(tmp, tmp, rscratch1, tmp2);
225 __ mov(rscratch1, matrix->magic_offset());
226 Address loc(tmp, rscratch1);
227
228 __ ldrb(tmp2, loc);
229 __ cbnz(tmp2, done);
230 __ mov(tmp2, 1);
231 __ strb(tmp2, loc);
232 __ bind(done);
233 }
234
235 void ShenandoahBarrierSetAssembler::read_barrier(MacroAssembler* masm, Register dst) {
236 if (ShenandoahReadBarrier) {
237 read_barrier_impl(masm, dst);
238 }
239 }
240
241 void ShenandoahBarrierSetAssembler::read_barrier_impl(MacroAssembler* masm, Register dst) {
242 assert(UseShenandoahGC && (ShenandoahReadBarrier || ShenandoahStoreValReadBarrier), "should be enabled");
243 Label is_null;
244 __ cbz(dst, is_null);
245 read_barrier_not_null_impl(masm, dst);
246 __ bind(is_null);
247 }
248
249 void ShenandoahBarrierSetAssembler::read_barrier_not_null(MacroAssembler* masm, Register dst) {
250 if (ShenandoahReadBarrier) {
251 read_barrier_not_null_impl(masm, dst);
252 }
253 }
254
255
256 void ShenandoahBarrierSetAssembler::read_barrier_not_null_impl(MacroAssembler* masm, Register dst) {
257 assert(UseShenandoahGC && (ShenandoahReadBarrier || ShenandoahStoreValReadBarrier), "should be enabled");
258 __ ldr(dst, Address(dst, BrooksPointer::byte_offset()));
259 }
260
261 void ShenandoahBarrierSetAssembler::write_barrier(MacroAssembler* masm, Register dst) {
262 if (ShenandoahWriteBarrier) {
263 write_barrier_impl(masm, dst);
264 }
265 }
266
267 void ShenandoahBarrierSetAssembler::write_barrier_impl(MacroAssembler* masm, Register dst) {
268 assert(UseShenandoahGC && (ShenandoahWriteBarrier || ShenandoahStoreValEnqueueBarrier), "should be enabled");
269 assert(dst != rscratch1, "different regs");
270 assert(dst != rscratch2, "Need rscratch2");
271
272 Label done;
273
274 Address gc_state(rthread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
275 __ ldrb(rscratch1, gc_state);
276 __ membar(Assembler::LoadLoad);
277
278 // Now check if evacuation is in progress.
279 read_barrier_not_null(masm, dst);
280
281 __ mov(rscratch2, ShenandoahHeap::EVACUATION | ShenandoahHeap::TRAVERSAL);
282 __ tst(rscratch1, rscratch2);
283 __ br(Assembler::EQ, done);
284
285 __ lsr(rscratch1, dst, ShenandoahHeapRegion::region_size_bytes_shift_jint());
286 __ mov(rscratch2, ShenandoahHeap::in_cset_fast_test_addr());
287 __ ldrb(rscratch2, Address(rscratch2, rscratch1));
288 __ tst(rscratch2, 0x1);
289 __ br(Assembler::EQ, done);
290
291 // Save possibly live regs.
292 RegSet live_regs = RegSet::range(r0, r4) - dst;
293 __ push(live_regs, sp);
294 __ strd(v0, __ pre(sp, 2 * -wordSize));
295
296 // Call into runtime
297 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_barrier_IRT), dst);
298
299 // Move result into dst reg.
300 __ mov(dst, r0);
301
302 // Restore possibly live regs.
303 __ ldrd(v0, __ post(sp, 2 * wordSize));
304 __ pop(live_regs, sp);
305
306 __ bind(done);
307 }
308
309 void ShenandoahBarrierSetAssembler::storeval_barrier(MacroAssembler* masm, Register dst, Register tmp) {
310 if (ShenandoahStoreValEnqueueBarrier) {
311 Label is_null;
312 __ cbz(dst, is_null);
313 write_barrier_impl(masm, dst);
314 __ bind(is_null);
315 // Save possibly live regs.
316 RegSet live_regs = RegSet::range(r0, r4) - dst;
317 __ push(live_regs, sp);
318 __ strd(v0, __ pre(sp, 2 * -wordSize));
319
320 satb_write_barrier_pre(masm, noreg, dst, rthread, tmp, true, false);
321
322 // Restore possibly live regs.
323 __ ldrd(v0, __ post(sp, 2 * wordSize));
324 __ pop(live_regs, sp);
325 }
326 if (ShenandoahStoreValReadBarrier) {
327 read_barrier_impl(masm, dst);
328 }
329 }
330
331 void ShenandoahBarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
332 Register dst, Address src, Register tmp1, Register tmp_thread) {
333 bool on_oop = type == T_OBJECT || type == T_ARRAY;
334 bool in_heap = (decorators & IN_HEAP) != 0;
335 bool on_weak = (decorators & ON_WEAK_OOP_REF) != 0;
336 bool on_phantom = (decorators & ON_PHANTOM_OOP_REF) != 0;
337 bool on_reference = on_weak || on_phantom;
338
339 if (in_heap) {
340 read_barrier_not_null(masm, src.base());
341 }
342
343 BarrierSetAssembler::load_at(masm, decorators, type, dst, src, tmp1, tmp_thread);
344 if (ShenandoahKeepAliveBarrier && on_oop && on_reference) {
345 __ enter();
346 satb_write_barrier_pre(masm /* masm */,
347 noreg /* obj */,
348 dst /* pre_val */,
349 rthread /* thread */,
350 tmp1 /* tmp */,
351 true /* tosca_live */,
352 true /* expand_call */);
353 __ leave();
354 }
355 }
356
357 void ShenandoahBarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
358 Address dst, Register val, Register tmp1, Register tmp2) {
359 bool on_oop = type == T_OBJECT || type == T_ARRAY;
360 bool in_heap = (decorators & IN_HEAP) != 0;
361 if (in_heap) {
362 write_barrier(masm, dst.base());
363 }
364 if (!on_oop) {
365 BarrierSetAssembler::store_at(masm, decorators, type, dst, val, tmp1, tmp2);
366 return;
367 }
368
369 // flatten object address if needed
370 if (dst.index() == noreg && dst.offset() == 0) {
371 if (dst.base() != r3) {
372 __ mov(r3, dst.base());
373 }
374 } else {
375 __ lea(r3, dst);
376 }
377
378 shenandoah_write_barrier_pre(masm,
379 r3 /* obj */,
380 tmp2 /* pre_val */,
381 rthread /* thread */,
382 tmp1 /* tmp */,
383 val != noreg /* tosca_live */,
384 false /* expand_call */);
385
386 if (val == noreg) {
387 BarrierSetAssembler::store_at(masm, decorators, type, Address(r3, 0), noreg, noreg, noreg);
388 } else {
389 storeval_barrier(masm, val, tmp1);
390 // G1 barrier needs uncompressed oop for region cross check.
391 Register new_val = val;
392 if (UseCompressedOops) {
393 new_val = rscratch2;
394 __ mov(new_val, val);
395 }
396 BarrierSetAssembler::store_at(masm, decorators, type, Address(r3, 0), val, noreg, noreg);
397 shenandoah_write_barrier_post(masm,
398 r3 /* store_adr */,
399 new_val /* new_val */,
400 rthread /* thread */,
401 tmp1 /* tmp */,
402 tmp2 /* tmp2 */);
403 }
404
405 }
406
407 void ShenandoahBarrierSetAssembler::obj_equals(MacroAssembler* masm, DecoratorSet decorators, Register op1, Register op2) {
408 __ cmp(op1, op2);
409 if (ShenandoahAcmpBarrier) {
410 Label done;
411 __ br(Assembler::EQ, done);
412 // The object may have been evacuated, but we won't see it without a
413 // membar here.
414 __ membar(Assembler::LoadStore| Assembler::LoadLoad);
415 read_barrier(masm, op1);
416 read_barrier(masm, op2);
417 __ cmp(op1, op2);
418 __ bind(done);
419 }
420 }
421
422 void ShenandoahBarrierSetAssembler::resolve_for_read(MacroAssembler* masm, DecoratorSet decorators, Register obj) {
423 bool oop_not_null = (decorators & OOP_NOT_NULL) != 0;
424 if (oop_not_null) {
425 read_barrier_not_null(masm, obj);
426 } else {
427 read_barrier(masm, obj);
428 }
429 }
430
431 void ShenandoahBarrierSetAssembler::resolve_for_write(MacroAssembler* masm, DecoratorSet decorators, Register obj) {
432 write_barrier(masm, obj);
433 }
434
435 void ShenandoahBarrierSetAssembler::cmpxchg_oop(MacroAssembler* masm, Register addr, Register expected, Register new_val,
436 bool acquire, bool release, bool weak, bool encode,
437 Register tmp1, Register tmp2, Register tmp3,
438 Register result) {
439
440 if (encode) {
441 storeval_barrier(masm, new_val, tmp3);
442 }
443
444 if (UseCompressedOops) {
445 if (encode) {
446 __ encode_heap_oop(tmp1, expected);
447 expected = tmp1;
448 __ encode_heap_oop(tmp2, new_val);
449 new_val = tmp2;
450 }
451 }
452 bool is_cae = (result != noreg);
453 bool is_narrow = UseCompressedOops;
454 Assembler::operand_size size = is_narrow ? Assembler::word : Assembler::xword;
455 if (! is_cae) result = rscratch1;
456
457 assert_different_registers(addr, expected, new_val, result, tmp3);
458
459 Label retry, done, fail;
460
461 // CAS, using LL/SC pair.
462 __ bind(retry);
463 __ load_exclusive(result, addr, size, acquire);
464 if (is_narrow) {
465 __ cmpw(result, expected);
466 } else {
467 __ cmp(result, expected);
468 }
469 __ br(Assembler::NE, fail);
470 __ store_exclusive(tmp3, new_val, addr, size, release);
471 if (weak) {
472 __ cmpw(tmp3, 0u); // If the store fails, return NE to our caller
473 } else {
474 __ cbnzw(tmp3, retry);
475 }
476 __ b(done);
477
478 __ bind(fail);
479 // Check if rb(expected)==rb(result)
480 // Shuffle registers so that we have memory value ready for next expected.
481 __ mov(tmp3, expected);
482 __ mov(expected, result);
483 if (is_narrow) {
484 __ decode_heap_oop(result, result);
485 __ decode_heap_oop(tmp3, tmp3);
486 }
487 __ resolve_for_read(0, result);
488 __ resolve_for_read(0, tmp3);
489 __ cmp(result, tmp3);
490 // Retry with expected now being the value we just loaded from addr.
491 __ br(Assembler::EQ, retry);
492 if (is_narrow && is_cae) {
493 // For cmp-and-exchange and narrow oops, we need to restore
494 // the compressed old-value. We moved it to 'expected' a few lines up.
495 __ mov(result, expected);
496 }
497 __ bind(done);
498
499 }
500
501 #ifdef COMPILER1
502
503 #undef __
504 #define __ ce->masm()->
505
506 void ShenandoahBarrierSetAssembler::gen_pre_barrier_stub(LIR_Assembler* ce, ShenandoahPreBarrierStub* stub) {
507 ShenandoahBarrierSetC1* bs = (ShenandoahBarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1();
508 // At this point we know that marking is in progress.
509 // If do_load() is true then we have to emit the
510 // load of the previous value; otherwise it has already
511 // been loaded into _pre_val.
512
513 __ bind(*stub->entry());
514
515 assert(stub->pre_val()->is_register(), "Precondition.");
516
517 Register pre_val_reg = stub->pre_val()->as_register();
518
519 if (stub->do_load()) {
520 ce->mem2reg(stub->addr(), stub->pre_val(), T_OBJECT, stub->patch_code(), stub->info(), false /*wide*/, false /*unaligned*/);
521 }
522 __ cbz(pre_val_reg, *stub->continuation());
523 ce->store_parameter(stub->pre_val()->as_register(), 0);
524 __ far_call(RuntimeAddress(bs->pre_barrier_c1_runtime_code_blob()->code_begin()));
525 __ b(*stub->continuation());
526 }
527
528 #undef __
529
530 #define __ sasm->
531
532 void ShenandoahBarrierSetAssembler::generate_c1_pre_barrier_runtime_stub(StubAssembler* sasm) {
533 __ prologue("shenandoah_pre_barrier", false);
534
535 // arg0 : previous value of memory
536
537 BarrierSet* bs = BarrierSet::barrier_set();
538
539 const Register pre_val = r0;
540 const Register thread = rthread;
541 const Register tmp = rscratch1;
542
543 Address queue_index(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset()));
544 Address buffer(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()));
545
546 Label done;
547 Label runtime;
548
549 // Is marking still active?
550 Address gc_state(thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
551 __ ldrb(tmp, gc_state);
552 __ mov(rscratch2, ShenandoahHeap::MARKING | ShenandoahHeap::TRAVERSAL);
553 __ tst(tmp, rscratch2);
554 __ br(Assembler::EQ, done);
555
556 // Can we store original value in the thread's buffer?
557 __ ldr(tmp, queue_index);
558 __ cbz(tmp, runtime);
559
560 __ sub(tmp, tmp, wordSize);
561 __ str(tmp, queue_index);
562 __ ldr(rscratch2, buffer);
563 __ add(tmp, tmp, rscratch2);
564 __ load_parameter(0, rscratch2);
565 __ str(rscratch2, Address(tmp, 0));
566 __ b(done);
567
568 __ bind(runtime);
569 __ push_call_clobbered_registers();
570 __ load_parameter(0, pre_val);
571 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), pre_val, thread);
572 __ pop_call_clobbered_registers();
573 __ bind(done);
574
575 __ epilogue();
576 }
577
578 #undef __
579
580 #endif // COMPILER1
581
582 address ShenandoahBarrierSetAssembler::shenandoah_wb() {
583 assert(_shenandoah_wb != NULL, "need write barrier stub");
584 return _shenandoah_wb;
585 }
586
587 address ShenandoahBarrierSetAssembler::shenandoah_wb_C() {
588 assert(_shenandoah_wb_C != NULL, "need write barrier stub");
589 return _shenandoah_wb_C;
590 }
591
592 #define __ cgen->assembler()->
593
594 // Shenandoah write barrier.
595 //
596 // Input:
597 // r0: OOP to evacuate. Not null.
598 //
599 // Output:
600 // r0: Pointer to evacuated OOP.
601 //
602 // Trash rscratch1, rscratch2. Preserve everything else.
603 address ShenandoahBarrierSetAssembler::generate_shenandoah_wb(StubCodeGenerator* cgen, bool c_abi, bool do_cset_test) {
604
605 __ align(6);
606 StubCodeMark mark(cgen, "StubRoutines", "shenandoah_wb");
607 address start = __ pc();
608
609 if (do_cset_test) {
610 Label work;
611 __ mov(rscratch2, ShenandoahHeap::in_cset_fast_test_addr());
612 __ lsr(rscratch1, r0, ShenandoahHeapRegion::region_size_bytes_shift_jint());
613 __ ldrb(rscratch2, Address(rscratch2, rscratch1));
614 __ tbnz(rscratch2, 0, work);
615 __ ret(lr);
616 __ bind(work);
617 }
618
619 Register obj = r0;
620
621 __ enter(); // required for proper stackwalking of RuntimeStub frame
622
623 if (!c_abi) {
624 __ push_call_clobbered_registers();
625 } else {
626 __ push_call_clobbered_fp_registers();
627 }
628
629 __ mov(lr, CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_barrier_JRT));
630 __ blrt(lr, 1, 0, MacroAssembler::ret_type_integral);
631 if (!c_abi) {
632 __ mov(rscratch1, obj);
633 __ pop_call_clobbered_registers();
634 __ mov(obj, rscratch1);
635 } else {
636 __ pop_call_clobbered_fp_registers();
637 }
638
639 __ leave(); // required for proper stackwalking of RuntimeStub frame
640 __ ret(lr);
641
642 return start;
643 }
644
645 #undef __
646
647 void ShenandoahBarrierSetAssembler::barrier_stubs_init() {
648 if (ShenandoahWriteBarrier || ShenandoahStoreValEnqueueBarrier) {
649 int stub_code_size = 2048;
650 ResourceMark rm;
651 BufferBlob* bb = BufferBlob::create("shenandoah_barrier_stubs", stub_code_size);
652 CodeBuffer buf(bb);
653 StubCodeGenerator cgen(&buf);
654 _shenandoah_wb = generate_shenandoah_wb(&cgen, false, true);
655 _shenandoah_wb_C = generate_shenandoah_wb(&cgen, true, !ShenandoahWriteBarrierCsetTestInIR);
656 }
657 }