1 /*
2 * Copyright (c) 2018, 2020, Red Hat, Inc. All rights reserved.
3 * Copyright (c) 2020, 2021, Huawei Technologies Co., Ltd. All rights reserved.
4 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
5 *
6 * This code is free software; you can redistribute it and/or modify it
7 * under the terms of the GNU General Public License version 2 only, as
8 * published by the Free Software Foundation.
9 *
10 * This code is distributed in the hope that it will be useful, but WITHOUT
11 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
12 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
13 * version 2 for more details (a copy is included in the LICENSE file that
14 * accompanied this code).
15 *
16 * You should have received a copy of the GNU General Public License version
17 * 2 along with this work; if not, write to the Free Software Foundation,
18 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
19 *
20 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
21 * or visit www.oracle.com if you need additional information or have any
22 * questions.
23 *
24 */
25
26 #include "precompiled.hpp"
27 #include "gc/shenandoah/shenandoahBarrierSet.hpp"
28 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp"
29 #include "gc/shenandoah/shenandoahForwarding.hpp"
30 #include "gc/shenandoah/shenandoahHeap.inline.hpp"
31 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
32 #include "gc/shenandoah/shenandoahRuntime.hpp"
33 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
34 #include "gc/shenandoah/heuristics/shenandoahHeuristics.hpp"
35 #include "interpreter/interpreter.hpp"
36 #include "interpreter/interp_masm.hpp"
37 #include "runtime/javaThread.hpp"
38 #include "runtime/sharedRuntime.hpp"
39 #ifdef COMPILER1
40 #include "c1/c1_LIRAssembler.hpp"
41 #include "c1/c1_MacroAssembler.hpp"
42 #include "gc/shenandoah/c1/shenandoahBarrierSetC1.hpp"
43 #endif
44
45 #define __ masm->
46
47 void ShenandoahBarrierSetAssembler::arraycopy_prologue(MacroAssembler* masm, DecoratorSet decorators, bool is_oop,
48 Register src, Register dst, Register count, RegSet saved_regs) {
49 if (is_oop) {
50 bool dest_uninitialized = (decorators & IS_DEST_UNINITIALIZED) != 0;
51 if ((ShenandoahSATBBarrier && !dest_uninitialized) || ShenandoahLoadRefBarrier) {
52
53 Label done;
54
55 // Avoid calling runtime if count == 0
56 __ beqz(count, done);
57
58 // Is GC active?
59 Address gc_state(xthread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
60 assert_different_registers(src, dst, count, t0);
61
62 __ lbu(t0, gc_state);
63 if (ShenandoahSATBBarrier && dest_uninitialized) {
64 __ test_bit(t0, t0, ShenandoahHeap::HAS_FORWARDED_BITPOS);
65 __ beqz(t0, done);
66 } else {
67 __ andi(t0, t0, ShenandoahHeap::HAS_FORWARDED | ShenandoahHeap::MARKING);
68 __ beqz(t0, done);
69 }
70
71 __ push_reg(saved_regs, sp);
72 if (UseCompressedOops) {
73 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::arraycopy_barrier_narrow_oop),
74 src, dst, count);
75 } else {
76 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::arraycopy_barrier_oop), src, dst, count);
77 }
78 __ pop_reg(saved_regs, sp);
79 __ bind(done);
80 }
81 }
82 }
83
84 void ShenandoahBarrierSetAssembler::shenandoah_write_barrier_pre(MacroAssembler* masm,
85 Register obj,
86 Register pre_val,
87 Register thread,
88 Register tmp,
89 bool tosca_live,
90 bool expand_call) {
91 if (ShenandoahSATBBarrier) {
92 satb_write_barrier_pre(masm, obj, pre_val, thread, tmp, t0, tosca_live, expand_call);
93 }
94 }
95
96 void ShenandoahBarrierSetAssembler::satb_write_barrier_pre(MacroAssembler* masm,
97 Register obj,
98 Register pre_val,
99 Register thread,
100 Register tmp1,
101 Register tmp2,
102 bool tosca_live,
103 bool expand_call) {
104 // If expand_call is true then we expand the call_VM_leaf macro
105 // directly to skip generating the check by
106 // InterpreterMacroAssembler::call_VM_leaf_base that checks _last_sp.
107 assert(thread == xthread, "must be");
108
109 Label done;
110 Label runtime;
111
112 assert_different_registers(obj, pre_val, tmp1, tmp2);
113 assert(pre_val != noreg && tmp1 != noreg && tmp2 != noreg, "expecting a register");
114
115 Address index(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset()));
116 Address buffer(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()));
117
118 // Is marking active?
119 Address gc_state(xthread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
120 __ lbu(t1, gc_state);
121 __ test_bit(t1, t1, ShenandoahHeap::MARKING_BITPOS);
122 __ beqz(t1, done);
123
124 // Do we need to load the previous value?
125 if (obj != noreg) {
126 __ load_heap_oop(pre_val, Address(obj, 0), noreg, noreg, AS_RAW);
127 }
128
129 // Is the previous value null?
130 __ beqz(pre_val, done);
131
132 // Can we store original value in the thread's buffer?
133 // Is index == 0?
134 // (The index field is typed as size_t.)
135 __ ld(tmp1, index); // tmp := *index_adr
136 __ beqz(tmp1, runtime); // tmp == 0? If yes, goto runtime
137
138 __ sub(tmp1, tmp1, wordSize); // tmp := tmp - wordSize
139 __ sd(tmp1, index); // *index_adr := tmp
140 __ ld(tmp2, buffer);
141 __ add(tmp1, tmp1, tmp2); // tmp := tmp + *buffer_adr
142
143 // Record the previous value
144 __ sd(pre_val, Address(tmp1, 0));
145 __ j(done);
146
147 __ bind(runtime);
148 // save the live input values
149 RegSet saved = RegSet::of(pre_val);
150 if (tosca_live) saved += RegSet::of(x10);
151 if (obj != noreg) saved += RegSet::of(obj);
152
153 __ push_reg(saved, sp);
154
155 // Calling the runtime using the regular call_VM_leaf mechanism generates
156 // code (generated by InterpreterMacroAssember::call_VM_leaf_base)
157 // that checks that the *(rfp+frame::interpreter_frame_last_sp) is null.
158 //
159 // If we care generating the pre-barrier without a frame (e.g. in the
160 // intrinsified Reference.get() routine) then ebp might be pointing to
161 // the caller frame and so this check will most likely fail at runtime.
162 //
163 // Expanding the call directly bypasses the generation of the check.
164 // So when we do not have have a full interpreter frame on the stack
165 // expand_call should be passed true.
166 if (expand_call) {
167 assert(pre_val != c_rarg1, "smashed arg");
168 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre), pre_val, thread);
169 } else {
170 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre), pre_val, thread);
171 }
172
173 __ pop_reg(saved, sp);
174
175 __ bind(done);
176 }
177
178 void ShenandoahBarrierSetAssembler::resolve_forward_pointer(MacroAssembler* masm, Register dst, Register tmp) {
179 assert(ShenandoahLoadRefBarrier || ShenandoahCASBarrier, "Should be enabled");
180
181 Label is_null;
182 __ beqz(dst, is_null);
183 resolve_forward_pointer_not_null(masm, dst, tmp);
184 __ bind(is_null);
185 }
186
187 // IMPORTANT: This must preserve all registers, even t0 and t1, except those explicitly
188 // passed in.
189 void ShenandoahBarrierSetAssembler::resolve_forward_pointer_not_null(MacroAssembler* masm, Register dst, Register tmp) {
190 assert(ShenandoahLoadRefBarrier || ShenandoahCASBarrier, "Should be enabled");
191 // The below loads the mark word, checks if the lowest two bits are
192 // set, and if so, clear the lowest two bits and copy the result
193 // to dst. Otherwise it leaves dst alone.
194 // Implementing this is surprisingly awkward. I do it here by:
195 // - Inverting the mark word
196 // - Test lowest two bits == 0
197 // - If so, set the lowest two bits
198 // - Invert the result back, and copy to dst
199 RegSet saved_regs = RegSet::of(t2);
200 bool borrow_reg = (tmp == noreg);
201 if (borrow_reg) {
202 // No free registers available. Make one useful.
203 tmp = t0;
204 if (tmp == dst) {
205 tmp = t1;
206 }
207 saved_regs += RegSet::of(tmp);
208 }
209
210 assert_different_registers(tmp, dst, t2);
211 __ push_reg(saved_regs, sp);
212
213 Label done;
214 __ ld(tmp, Address(dst, oopDesc::mark_offset_in_bytes()));
215 __ xori(tmp, tmp, -1); // eon with 0 is equivalent to XOR with -1
216 __ andi(t2, tmp, markWord::lock_mask_in_place);
217 __ bnez(t2, done);
218 __ ori(tmp, tmp, markWord::marked_value);
219 __ xori(dst, tmp, -1); // eon with 0 is equivalent to XOR with -1
220 __ bind(done);
221
222 __ pop_reg(saved_regs, sp);
223 }
224
225 void ShenandoahBarrierSetAssembler::load_reference_barrier(MacroAssembler* masm,
226 Register dst,
227 Address load_addr,
228 DecoratorSet decorators) {
229 assert(ShenandoahLoadRefBarrier, "Should be enabled");
230 assert(dst != t1 && load_addr.base() != t1, "need t1");
231 assert_different_registers(load_addr.base(), t0, t1);
232
233 bool is_strong = ShenandoahBarrierSet::is_strong_access(decorators);
234 bool is_weak = ShenandoahBarrierSet::is_weak_access(decorators);
235 bool is_phantom = ShenandoahBarrierSet::is_phantom_access(decorators);
236 bool is_native = ShenandoahBarrierSet::is_native_access(decorators);
237 bool is_narrow = UseCompressedOops && !is_native;
238
239 Label heap_stable, not_cset;
240 __ enter();
241 Address gc_state(xthread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
242 __ lbu(t1, gc_state);
243
244 // Check for heap stability
245 if (is_strong) {
246 __ test_bit(t1, t1, ShenandoahHeap::HAS_FORWARDED_BITPOS);
247 __ beqz(t1, heap_stable);
248 } else {
249 Label lrb;
250 __ test_bit(t0, t1, ShenandoahHeap::WEAK_ROOTS_BITPOS);
251 __ bnez(t0, lrb);
252 __ test_bit(t0, t1, ShenandoahHeap::HAS_FORWARDED_BITPOS);
253 __ beqz(t0, heap_stable);
254 __ bind(lrb);
255 }
256
257 // use x11 for load address
258 Register result_dst = dst;
259 if (dst == x11) {
260 __ mv(t1, dst);
261 dst = t1;
262 }
263
264 // Save x10 and x11, unless it is an output register
265 RegSet saved_regs = RegSet::of(x10, x11) - result_dst;
266 __ push_reg(saved_regs, sp);
267 __ la(x11, load_addr);
268 __ mv(x10, dst);
269
270 // Test for in-cset
271 if (is_strong) {
272 __ mv(t1, ShenandoahHeap::in_cset_fast_test_addr());
273 __ srli(t0, x10, ShenandoahHeapRegion::region_size_bytes_shift_jint());
274 __ add(t1, t1, t0);
275 __ lbu(t1, Address(t1));
276 __ test_bit(t0, t1, 0);
277 __ beqz(t0, not_cset);
278 }
279
280 __ push_call_clobbered_registers();
281 address target = nullptr;
282 if (is_strong) {
283 if (is_narrow) {
284 target = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong_narrow);
285 } else {
286 target = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong);
287 }
288 } else if (is_weak) {
289 if (is_narrow) {
290 target = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak_narrow);
291 } else {
292 target = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak);
293 }
294 } else {
295 assert(is_phantom, "only remaining strength");
296 assert(!is_narrow, "phantom access cannot be narrow");
297 target = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak);
298 }
299 __ rt_call(target);
300 __ mv(t0, x10);
301 __ pop_call_clobbered_registers();
302 __ mv(x10, t0);
303 __ bind(not_cset);
304 __ mv(result_dst, x10);
305 __ pop_reg(saved_regs, sp);
306
307 __ bind(heap_stable);
308 __ leave();
309 }
310
311 //
312 // Arguments:
313 //
314 // Inputs:
315 // src: oop location to load from, might be clobbered
316 //
317 // Output:
318 // dst: oop loaded from src location
319 //
320 // Kill:
321 // x30 (tmp reg)
322 //
323 // Alias:
324 // dst: x30 (might use x30 as temporary output register to avoid clobbering src)
325 //
326 void ShenandoahBarrierSetAssembler::load_at(MacroAssembler* masm,
327 DecoratorSet decorators,
328 BasicType type,
329 Register dst,
330 Address src,
331 Register tmp1,
332 Register tmp2) {
333 // 1: non-reference load, no additional barrier is needed
334 if (!is_reference_type(type)) {
335 BarrierSetAssembler::load_at(masm, decorators, type, dst, src, tmp1, tmp2);
336 return;
337 }
338
339 // 2: load a reference from src location and apply LRB if needed
340 if (ShenandoahBarrierSet::need_load_reference_barrier(decorators, type)) {
341 Register result_dst = dst;
342
343 // Preserve src location for LRB
344 RegSet saved_regs;
345 if (dst == src.base()) {
346 dst = (src.base() == x28) ? x29 : x28;
347 saved_regs = RegSet::of(dst);
348 __ push_reg(saved_regs, sp);
349 }
350 assert_different_registers(dst, src.base());
351
352 BarrierSetAssembler::load_at(masm, decorators, type, dst, src, tmp1, tmp2);
353
354 load_reference_barrier(masm, dst, src, decorators);
355
356 if (dst != result_dst) {
357 __ mv(result_dst, dst);
358 dst = result_dst;
359 }
360
361 if (saved_regs.bits() != 0) {
362 __ pop_reg(saved_regs, sp);
363 }
364 } else {
365 BarrierSetAssembler::load_at(masm, decorators, type, dst, src, tmp1, tmp2);
366 }
367
368 // 3: apply keep-alive barrier if needed
369 if (ShenandoahBarrierSet::need_keep_alive_barrier(decorators, type)) {
370 __ enter();
371 __ push_call_clobbered_registers();
372 satb_write_barrier_pre(masm /* masm */,
373 noreg /* obj */,
374 dst /* pre_val */,
375 xthread /* thread */,
376 tmp1 /* tmp1 */,
377 tmp2 /* tmp2 */,
378 true /* tosca_live */,
379 true /* expand_call */);
380 __ pop_call_clobbered_registers();
381 __ leave();
382 }
383 }
384
385 void ShenandoahBarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
386 Address dst, Register val, Register tmp1, Register tmp2, Register tmp3) {
387 bool on_oop = is_reference_type(type);
388 if (!on_oop) {
389 BarrierSetAssembler::store_at(masm, decorators, type, dst, val, tmp1, tmp2, tmp3);
390 return;
391 }
392
393 // flatten object address if needed
394 if (dst.offset() == 0) {
395 if (dst.base() != tmp3) {
396 __ mv(tmp3, dst.base());
397 }
398 } else {
399 __ la(tmp3, dst);
400 }
401
402 shenandoah_write_barrier_pre(masm,
403 tmp3 /* obj */,
404 tmp2 /* pre_val */,
405 xthread /* thread */,
406 tmp1 /* tmp */,
407 val != noreg /* tosca_live */,
408 false /* expand_call */);
409
410 if (val == noreg) {
411 BarrierSetAssembler::store_at(masm, decorators, type, Address(tmp3, 0), noreg, noreg, noreg, noreg);
412 } else {
413 // Barrier needs uncompressed oop for region cross check.
414 Register new_val = val;
415 if (UseCompressedOops) {
416 new_val = t1;
417 __ mv(new_val, val);
418 }
419 BarrierSetAssembler::store_at(masm, decorators, type, Address(tmp3, 0), val, noreg, noreg, noreg);
420 }
421 }
422
423 void ShenandoahBarrierSetAssembler::try_resolve_jobject_in_native(MacroAssembler* masm, Register jni_env,
424 Register obj, Register tmp, Label& slowpath) {
425 Label done;
426 // Resolve jobject
427 BarrierSetAssembler::try_resolve_jobject_in_native(masm, jni_env, obj, tmp, slowpath);
428
429 // Check for null.
430 __ beqz(obj, done);
431
432 assert(obj != t1, "need t1");
433 Address gc_state(jni_env, ShenandoahThreadLocalData::gc_state_offset() - JavaThread::jni_environment_offset());
434 __ lbu(t1, gc_state);
435
436 // Check for heap in evacuation phase
437 __ test_bit(t0, t1, ShenandoahHeap::EVACUATION_BITPOS);
438 __ bnez(t0, slowpath);
439
440 __ bind(done);
441 }
442
443 // Special Shenandoah CAS implementation that handles false negatives due
444 // to concurrent evacuation. The service is more complex than a
445 // traditional CAS operation because the CAS operation is intended to
446 // succeed if the reference at addr exactly matches expected or if the
447 // reference at addr holds a pointer to a from-space object that has
448 // been relocated to the location named by expected. There are two
449 // races that must be addressed:
450 // a) A parallel thread may mutate the contents of addr so that it points
451 // to a different object. In this case, the CAS operation should fail.
452 // b) A parallel thread may heal the contents of addr, replacing a
453 // from-space pointer held in addr with the to-space pointer
454 // representing the new location of the object.
455 // Upon entry to cmpxchg_oop, it is assured that new_val equals null
456 // or it refers to an object that is not being evacuated out of
457 // from-space, or it refers to the to-space version of an object that
458 // is being evacuated out of from-space.
459 //
460 // By default the value held in the result register following execution
461 // of the generated code sequence is 0 to indicate failure of CAS,
462 // non-zero to indicate success. If is_cae, the result is the value most
463 // recently fetched from addr rather than a boolean success indicator.
464 //
465 // Clobbers t0, t1
466 void ShenandoahBarrierSetAssembler::cmpxchg_oop(MacroAssembler* masm,
467 Register addr,
468 Register expected,
469 Register new_val,
470 Assembler::Aqrl acquire,
471 Assembler::Aqrl release,
472 bool is_cae,
473 Register result) {
474 bool is_narrow = UseCompressedOops;
475 Assembler::operand_size size = is_narrow ? Assembler::uint32 : Assembler::int64;
476
477 assert_different_registers(addr, expected, t0, t1);
478 assert_different_registers(addr, new_val, t0, t1);
479
480 Label retry, success, fail, done;
481
482 __ bind(retry);
483
484 // Step1: Try to CAS.
485 __ cmpxchg(addr, expected, new_val, size, acquire, release, /* result */ t1);
486
487 // If success, then we are done.
488 __ beq(expected, t1, success);
489
490 // Step2: CAS failed, check the forwarded pointer.
491 __ mv(t0, t1);
492
493 if (is_narrow) {
494 __ decode_heap_oop(t0, t0);
495 }
496 resolve_forward_pointer(masm, t0);
497
498 __ encode_heap_oop(t0, t0);
499
500 // Report failure when the forwarded oop was not expected.
501 __ bne(t0, expected, fail);
502
503 // Step 3: CAS again using the forwarded oop.
504 __ cmpxchg(addr, t1, new_val, size, acquire, release, /* result */ t0);
505
506 // Retry when failed.
507 __ bne(t0, t1, retry);
508
509 __ bind(success);
510 if (is_cae) {
511 __ mv(result, expected);
512 } else {
513 __ mv(result, 1);
514 }
515 __ j(done);
516
517 __ bind(fail);
518 if (is_cae) {
519 __ mv(result, t0);
520 } else {
521 __ mv(result, zr);
522 }
523
524 __ bind(done);
525 }
526
527 #undef __
528
529 #ifdef COMPILER1
530
531 #define __ ce->masm()->
532
533 void ShenandoahBarrierSetAssembler::gen_pre_barrier_stub(LIR_Assembler* ce, ShenandoahPreBarrierStub* stub) {
534 ShenandoahBarrierSetC1* bs = (ShenandoahBarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1();
535 // At this point we know that marking is in progress.
536 // If do_load() is true then we have to emit the
537 // load of the previous value; otherwise it has already
538 // been loaded into _pre_val.
539 __ bind(*stub->entry());
540
541 assert(stub->pre_val()->is_register(), "Precondition.");
542
543 Register pre_val_reg = stub->pre_val()->as_register();
544
545 if (stub->do_load()) {
546 ce->mem2reg(stub->addr(), stub->pre_val(), T_OBJECT, stub->patch_code(), stub->info(), false /* wide */);
547 }
548 __ beqz(pre_val_reg, *stub->continuation(), /* is_far */ true);
549 ce->store_parameter(stub->pre_val()->as_register(), 0);
550 __ far_call(RuntimeAddress(bs->pre_barrier_c1_runtime_code_blob()->code_begin()));
551 __ j(*stub->continuation());
552 }
553
554 void ShenandoahBarrierSetAssembler::gen_load_reference_barrier_stub(LIR_Assembler* ce,
555 ShenandoahLoadReferenceBarrierStub* stub) {
556 ShenandoahBarrierSetC1* bs = (ShenandoahBarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1();
557 __ bind(*stub->entry());
558
559 DecoratorSet decorators = stub->decorators();
560 bool is_strong = ShenandoahBarrierSet::is_strong_access(decorators);
561 bool is_weak = ShenandoahBarrierSet::is_weak_access(decorators);
562 bool is_phantom = ShenandoahBarrierSet::is_phantom_access(decorators);
563 bool is_native = ShenandoahBarrierSet::is_native_access(decorators);
564
565 Register obj = stub->obj()->as_register();
566 Register res = stub->result()->as_register();
567 Register addr = stub->addr()->as_pointer_register();
568 Register tmp1 = stub->tmp1()->as_register();
569 Register tmp2 = stub->tmp2()->as_register();
570
571 assert(res == x10, "result must arrive in x10");
572 assert_different_registers(tmp1, tmp2, t0);
573
574 if (res != obj) {
575 __ mv(res, obj);
576 }
577
578 if (is_strong) {
579 // Check for object in cset.
580 __ mv(tmp2, ShenandoahHeap::in_cset_fast_test_addr());
581 __ srli(tmp1, res, ShenandoahHeapRegion::region_size_bytes_shift_jint());
582 __ add(tmp2, tmp2, tmp1);
583 __ lbu(tmp2, Address(tmp2));
584 __ beqz(tmp2, *stub->continuation(), true /* is_far */);
585 }
586
587 ce->store_parameter(res, 0);
588 ce->store_parameter(addr, 1);
589
590 if (is_strong) {
591 if (is_native) {
592 __ far_call(RuntimeAddress(bs->load_reference_barrier_strong_native_rt_code_blob()->code_begin()));
593 } else {
594 __ far_call(RuntimeAddress(bs->load_reference_barrier_strong_rt_code_blob()->code_begin()));
595 }
596 } else if (is_weak) {
597 __ far_call(RuntimeAddress(bs->load_reference_barrier_weak_rt_code_blob()->code_begin()));
598 } else {
599 assert(is_phantom, "only remaining strength");
600 __ far_call(RuntimeAddress(bs->load_reference_barrier_phantom_rt_code_blob()->code_begin()));
601 }
602
603 __ j(*stub->continuation());
604 }
605
606 #undef __
607
608 #define __ sasm->
609
610 void ShenandoahBarrierSetAssembler::generate_c1_pre_barrier_runtime_stub(StubAssembler* sasm) {
611 __ prologue("shenandoah_pre_barrier", false);
612
613 // arg0 : previous value of memory
614
615 BarrierSet* bs = BarrierSet::barrier_set();
616
617 const Register pre_val = x10;
618 const Register thread = xthread;
619 const Register tmp = t0;
620
621 Address queue_index(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset()));
622 Address buffer(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()));
623
624 Label done;
625 Label runtime;
626
627 // Is marking still active?
628 Address gc_state(thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
629 __ lb(tmp, gc_state);
630 __ test_bit(tmp, tmp, ShenandoahHeap::MARKING_BITPOS);
631 __ beqz(tmp, done);
632
633 // Can we store original value in the thread's buffer?
634 __ ld(tmp, queue_index);
635 __ beqz(tmp, runtime);
636
637 __ sub(tmp, tmp, wordSize);
638 __ sd(tmp, queue_index);
639 __ ld(t1, buffer);
640 __ add(tmp, tmp, t1);
641 __ load_parameter(0, t1);
642 __ sd(t1, Address(tmp, 0));
643 __ j(done);
644
645 __ bind(runtime);
646 __ push_call_clobbered_registers();
647 __ load_parameter(0, pre_val);
648 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre), pre_val, thread);
649 __ pop_call_clobbered_registers();
650 __ bind(done);
651
652 __ epilogue();
653 }
654
655 void ShenandoahBarrierSetAssembler::generate_c1_load_reference_barrier_runtime_stub(StubAssembler* sasm,
656 DecoratorSet decorators) {
657 __ prologue("shenandoah_load_reference_barrier", false);
658 // arg0 : object to be resolved
659
660 __ push_call_clobbered_registers();
661 __ load_parameter(0, x10);
662 __ load_parameter(1, x11);
663
664 bool is_strong = ShenandoahBarrierSet::is_strong_access(decorators);
665 bool is_weak = ShenandoahBarrierSet::is_weak_access(decorators);
666 bool is_phantom = ShenandoahBarrierSet::is_phantom_access(decorators);
667 bool is_native = ShenandoahBarrierSet::is_native_access(decorators);
668 address target = nullptr;
669 if (is_strong) {
670 if (is_native) {
671 target = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong);
672 } else {
673 if (UseCompressedOops) {
674 target = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong_narrow);
675 } else {
676 target = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_strong);
677 }
678 }
679 } else if (is_weak) {
680 assert(!is_native, "weak must not be called off-heap");
681 if (UseCompressedOops) {
682 target = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak_narrow);
683 } else {
684 target = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_weak);
685 }
686 } else {
687 assert(is_phantom, "only remaining strength");
688 assert(is_native, "phantom must only be called off-heap");
689 target = CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_phantom);
690 }
691 __ rt_call(target);
692 __ mv(t0, x10);
693 __ pop_call_clobbered_registers();
694 __ mv(x10, t0);
695
696 __ epilogue();
697 }
698
699 #undef __
700
701 #endif // COMPILER1