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/shenandoahHeuristics.hpp"
31 #include "gc/shenandoah/shenandoahRuntime.hpp"
32 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
33 #include "interpreter/interpreter.hpp"
34 #include "interpreter/interp_masm.hpp"
35 #include "runtime/sharedRuntime.hpp"
36 #include "runtime/thread.hpp"
37 #include "utilities/macros.hpp"
38 #ifdef COMPILER1
39 #include "c1/c1_LIRAssembler.hpp"
40 #include "c1/c1_MacroAssembler.hpp"
41 #include "gc/shenandoah/c1/shenandoahBarrierSetC1.hpp"
42 #endif
43
44 #define __ masm->
45
46 address ShenandoahBarrierSetAssembler::_shenandoah_wb = NULL;
47 address ShenandoahBarrierSetAssembler::_shenandoah_wb_C = NULL;
48
49 void ShenandoahBarrierSetAssembler::arraycopy_prologue(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
50 Register src, Register dst, Register count) {
51
52 bool checkcast = (decorators & ARRAYCOPY_CHECKCAST) != 0;
53 bool disjoint = (decorators & ARRAYCOPY_DISJOINT) != 0;
54 bool obj_int = type == T_OBJECT LP64_ONLY(&& UseCompressedOops);
55 bool dest_uninitialized = (decorators & IS_DEST_UNINITIALIZED) != 0;
56
57 if (type == T_OBJECT || type == T_ARRAY) {
58 #ifdef _LP64
59 if (!checkcast && !obj_int) {
60 // Save count for barrier
61 __ movptr(r11, count);
62 } else if (disjoint && obj_int) {
63 // Save dst in r11 in the disjoint case
64 __ movq(r11, dst);
65 }
66 #else
67 if (disjoint) {
68 __ mov(rdx, dst); // save 'to'
69 }
70 #endif
71
72 if (!dest_uninitialized && !ShenandoahHeap::heap()->heuristics()->can_do_traversal_gc()) {
73 Register thread = NOT_LP64(rax) LP64_ONLY(r15_thread);
74 #ifndef _LP64
75 __ push(thread);
76 __ get_thread(thread);
77 #endif
78
79 Label filtered;
80 Address in_progress(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_active_offset()));
81 // Is marking active?
82 if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) {
83 __ cmpl(in_progress, 0);
84 } else {
85 assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "Assumption");
86 __ cmpb(in_progress, 0);
87 }
88
89 NOT_LP64(__ pop(thread);)
90
91 __ jcc(Assembler::equal, filtered);
92
93 __ pusha(); // push registers
94 #ifdef _LP64
95 if (count == c_rarg0) {
96 if (dst == c_rarg1) {
97 // exactly backwards!!
98 __ xchgptr(c_rarg1, c_rarg0);
99 } else {
100 __ movptr(c_rarg1, count);
101 __ movptr(c_rarg0, dst);
102 }
103 } else {
104 __ movptr(c_rarg0, dst);
105 __ movptr(c_rarg1, count);
106 }
107 if (UseCompressedOops) {
108 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_pre_narrow_oop_entry), 2);
109 } else {
110 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_pre_oop_entry), 2);
111 }
112 #else
113 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_pre_oop_entry),
114 dst, count);
115 #endif
116 __ popa();
117 __ bind(filtered);
118 }
119 }
120
121 }
122
123 void ShenandoahBarrierSetAssembler::arraycopy_epilogue(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
124 Register src, Register dst, Register count) {
125 bool checkcast = (decorators & ARRAYCOPY_CHECKCAST) != 0;
126 bool disjoint = (decorators & ARRAYCOPY_DISJOINT) != 0;
127 bool obj_int = type == T_OBJECT LP64_ONLY(&& UseCompressedOops);
128 Register tmp = rax;
129
130 if (type == T_OBJECT || type == T_ARRAY) {
131 #ifdef _LP64
132 if (!checkcast && !obj_int) {
133 // Save count for barrier
134 count = r11;
135 } else if (disjoint && obj_int) {
136 // Use the saved dst in the disjoint case
137 dst = r11;
138 } else if (checkcast) {
139 tmp = rscratch1;
140 }
141 #else
142 if (disjoint) {
143 __ mov(dst, rdx); // restore 'to'
144 }
145 #endif
146
147 __ pusha(); // push registers (overkill)
148 #ifdef _LP64
149 if (c_rarg0 == count) { // On win64 c_rarg0 == rcx
150 assert_different_registers(c_rarg1, dst);
151 __ mov(c_rarg1, count);
152 __ mov(c_rarg0, dst);
153 } else {
154 assert_different_registers(c_rarg0, count);
155 __ mov(c_rarg0, dst);
156 __ mov(c_rarg1, count);
157 }
158 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_post_entry), 2);
159 #else
160 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_array_post_entry),
161 dst, count);
162 #endif
163 __ popa();
164 }
165 }
166
167 void ShenandoahBarrierSetAssembler::shenandoah_write_barrier_pre(MacroAssembler* masm,
168 Register obj,
169 Register pre_val,
170 Register thread,
171 Register tmp,
172 bool tosca_live,
173 bool expand_call) {
174
175 if (ShenandoahSATBBarrier) {
176 satb_write_barrier_pre(masm, obj, pre_val, thread, tmp, tosca_live, expand_call);
177 }
178 }
179
180 void ShenandoahBarrierSetAssembler::satb_write_barrier_pre(MacroAssembler* masm,
181 Register obj,
182 Register pre_val,
183 Register thread,
184 Register tmp,
185 bool tosca_live,
186 bool expand_call) {
187 // If expand_call is true then we expand the call_VM_leaf macro
188 // directly to skip generating the check by
189 // InterpreterMacroAssembler::call_VM_leaf_base that checks _last_sp.
190
191 #ifdef _LP64
192 assert(thread == r15_thread, "must be");
193 #endif // _LP64
194
195 Label done;
196 Label runtime;
197
198 assert(pre_val != noreg, "check this code");
199
200 if (obj != noreg) {
201 assert_different_registers(obj, pre_val, tmp);
202 assert(pre_val != rax, "check this code");
203 }
204
205 Address in_progress(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_active_offset()));
206 Address index(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset()));
207 Address buffer(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()));
208
209 Address gc_state(thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
210 __ testb(gc_state, ShenandoahHeap::MARKING | ShenandoahHeap::TRAVERSAL);
211 __ jcc(Assembler::zero, done);
212
213 // Do we need to load the previous value?
214 if (obj != noreg) {
215 __ load_heap_oop(pre_val, Address(obj, 0), noreg, noreg, AS_RAW);
216 }
217
218 // Is the previous value null?
219 __ cmpptr(pre_val, (int32_t) NULL_WORD);
220 __ jcc(Assembler::equal, done);
221
222 // Can we store original value in the thread's buffer?
223 // Is index == 0?
224 // (The index field is typed as size_t.)
225
226 __ movptr(tmp, index); // tmp := *index_adr
227 __ cmpptr(tmp, 0); // tmp == 0?
228 __ jcc(Assembler::equal, runtime); // If yes, goto runtime
229
230 __ subptr(tmp, wordSize); // tmp := tmp - wordSize
231 __ movptr(index, tmp); // *index_adr := tmp
232 __ addptr(tmp, buffer); // tmp := tmp + *buffer_adr
233
234 // Record the previous value
235 __ movptr(Address(tmp, 0), pre_val);
236 __ jmp(done);
237
238 __ bind(runtime);
239 // save the live input values
240 if(tosca_live) __ push(rax);
241
242 if (obj != noreg && obj != rax)
243 __ push(obj);
244
245 if (pre_val != rax)
246 __ push(pre_val);
247
248 // Calling the runtime using the regular call_VM_leaf mechanism generates
249 // code (generated by InterpreterMacroAssember::call_VM_leaf_base)
250 // that checks that the *(ebp+frame::interpreter_frame_last_sp) == NULL.
251 //
252 // If we care generating the pre-barrier without a frame (e.g. in the
253 // intrinsified Reference.get() routine) then ebp might be pointing to
254 // the caller frame and so this check will most likely fail at runtime.
255 //
256 // Expanding the call directly bypasses the generation of the check.
257 // So when we do not have have a full interpreter frame on the stack
258 // expand_call should be passed true.
259
260 NOT_LP64( __ push(thread); )
261
262 #ifdef _LP64
263 // We move pre_val into c_rarg0 early, in order to avoid smashing it, should
264 // pre_val be c_rarg1 (where the call prologue would copy thread argument).
265 // Note: this should not accidentally smash thread, because thread is always r15.
266 assert(thread != c_rarg0, "smashed arg");
267 if (c_rarg0 != pre_val) {
268 __ mov(c_rarg0, pre_val);
269 }
270 #endif
271
272 if (expand_call) {
273 LP64_ONLY( assert(pre_val != c_rarg1, "smashed arg"); )
274 #ifdef _LP64
275 if (c_rarg1 != thread) {
276 __ mov(c_rarg1, thread);
277 }
278 // Already moved pre_val into c_rarg0 above
279 #else
280 __ push(thread);
281 __ push(pre_val);
282 #endif
283 __ MacroAssembler::call_VM_leaf_base(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), 2);
284 } else {
285 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), LP64_ONLY(c_rarg0) NOT_LP64(pre_val), thread);
286 }
287
288 NOT_LP64( __ pop(thread); )
289
290 // save the live input values
291 if (pre_val != rax)
292 __ pop(pre_val);
293
294 if (obj != noreg && obj != rax)
295 __ pop(obj);
296
297 if(tosca_live) __ pop(rax);
298
299 __ bind(done);
300 }
301
302 void ShenandoahBarrierSetAssembler::shenandoah_write_barrier_post(MacroAssembler* masm,
303 Register store_addr,
304 Register new_val,
305 Register thread,
306 Register tmp,
307 Register tmp2) {
308 assert(UseShenandoahGC, "why else should we be here?");
309
310 if (! UseShenandoahMatrix) {
311 // No need for that barrier if not using matrix.
312 return;
313 }
314
315 Label done;
316 __ testptr(new_val, new_val);
317 __ jcc(Assembler::zero, done);
318 ShenandoahConnectionMatrix* matrix = ShenandoahHeap::heap()->connection_matrix();
319 address matrix_addr = matrix->matrix_addr();
320 __ movptr(rscratch1, (intptr_t) ShenandoahHeap::heap()->base());
321 // Compute to-region index
322 __ movptr(tmp, new_val);
323 __ subptr(tmp, rscratch1);
324 __ shrptr(tmp, ShenandoahHeapRegion::region_size_bytes_shift_jint());
325 // Compute from-region index
326 __ movptr(tmp2, store_addr);
327 __ subptr(tmp2, rscratch1);
328 __ shrptr(tmp2, ShenandoahHeapRegion::region_size_bytes_shift_jint());
329 // Compute matrix index
330 __ imulptr(tmp, tmp, matrix->stride_jint());
331 __ addptr(tmp, tmp2);
332 // Address is _matrix[to * stride + from]
333 __ movptr(rscratch1, (intptr_t) matrix_addr);
334 // Test if the element is already set.
335 __ cmpb(Address(rscratch1, tmp, Address::times_1), 0);
336 __ jcc(Assembler::notEqual, done);
337 // Store true, if not yet set.
338 __ movb(Address(rscratch1, tmp, Address::times_1), 1);
339 __ bind(done);
340 }
341
342 void ShenandoahBarrierSetAssembler::read_barrier(MacroAssembler* masm, Register dst) {
343 if (ShenandoahReadBarrier) {
344 read_barrier_impl(masm, dst);
345 }
346 }
347
348 void ShenandoahBarrierSetAssembler::read_barrier_impl(MacroAssembler* masm, Register dst) {
349 assert(UseShenandoahGC && (ShenandoahReadBarrier || ShenandoahStoreValReadBarrier), "should be enabled");
350 Label is_null;
351 __ testptr(dst, dst);
352 __ jcc(Assembler::zero, is_null);
353 read_barrier_not_null_impl(masm, dst);
354 __ bind(is_null);
355 }
356
357 void ShenandoahBarrierSetAssembler::read_barrier_not_null(MacroAssembler* masm, Register dst) {
358 if (ShenandoahReadBarrier) {
359 read_barrier_not_null_impl(masm, dst);
360 }
361 }
362
363 void ShenandoahBarrierSetAssembler::read_barrier_not_null_impl(MacroAssembler* masm, Register dst) {
364 assert(UseShenandoahGC && (ShenandoahReadBarrier || ShenandoahStoreValReadBarrier), "should be enabled");
365 __ movptr(dst, Address(dst, BrooksPointer::byte_offset()));
366 }
367
368
369 void ShenandoahBarrierSetAssembler::write_barrier(MacroAssembler* masm, Register dst) {
370 if (ShenandoahWriteBarrier) {
371 write_barrier_impl(masm, dst);
372 }
373 }
374
375 void ShenandoahBarrierSetAssembler::write_barrier_impl(MacroAssembler* masm, Register dst) {
376 assert(UseShenandoahGC && (ShenandoahWriteBarrier || ShenandoahStoreValEnqueueBarrier), "Should be enabled");
377 #ifdef _LP64
378 Label done;
379
380 Address gc_state(r15_thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
381 __ testb(gc_state, ShenandoahHeap::HAS_FORWARDED | ShenandoahHeap::EVACUATION | ShenandoahHeap::TRAVERSAL);
382 __ jccb(Assembler::zero, done);
383
384 // Heap is unstable, need to perform the read-barrier even if WB is inactive
385 if (ShenandoahWriteBarrierRB) {
386 read_barrier_not_null(masm, dst);
387 }
388
389 __ testb(gc_state, ShenandoahHeap::EVACUATION | ShenandoahHeap::TRAVERSAL);
390 __ jccb(Assembler::zero, done);
391
392 if (dst != rax) {
393 __ xchgptr(dst, rax); // Move obj into rax and save rax into obj.
394 }
395
396 __ call(RuntimeAddress(CAST_FROM_FN_PTR(address, ShenandoahBarrierSetAssembler::shenandoah_wb())));
397
398 if (dst != rax) {
399 __ xchgptr(rax, dst); // Swap back obj with rax.
400 }
401
402 __ bind(done);
403 #else
404 Unimplemented();
405 #endif
406 }
407
408 void ShenandoahBarrierSetAssembler::storeval_barrier(MacroAssembler* masm, Register dst, Register tmp) {
409 if (ShenandoahStoreValReadBarrier || ShenandoahStoreValEnqueueBarrier) {
410 storeval_barrier_impl(masm, dst, tmp);
411 }
412 }
413
414 void ShenandoahBarrierSetAssembler::storeval_barrier_impl(MacroAssembler* masm, Register dst, Register tmp) {
415 assert(UseShenandoahGC && (ShenandoahStoreValReadBarrier || ShenandoahStoreValEnqueueBarrier), "should be enabled");
416
417 if (dst == noreg) return;
418
419 #ifdef _LP64
420 if (ShenandoahStoreValEnqueueBarrier) {
421 Label is_null;
422 __ testptr(dst, dst);
423 __ jcc(Assembler::zero, is_null);
424 write_barrier_impl(masm, dst);
425 __ bind(is_null);
426
427 // The set of registers to be saved+restored is the same as in the write-barrier above.
428 // Those are the commonly used registers in the interpreter.
429 __ pusha();
430 // __ push_callee_saved_registers();
431 __ subptr(rsp, 2 * Interpreter::stackElementSize);
432 __ movdbl(Address(rsp, 0), xmm0);
433
434 satb_write_barrier_pre(masm, noreg, dst, r15_thread, tmp, true, false);
435 __ movdbl(xmm0, Address(rsp, 0));
436 __ addptr(rsp, 2 * Interpreter::stackElementSize);
437 //__ pop_callee_saved_registers();
438 __ popa();
439 }
440 if (ShenandoahStoreValReadBarrier) {
441 read_barrier_impl(masm, dst);
442 }
443 #else
444 Unimplemented();
445 #endif
446 }
447
448 void ShenandoahBarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
449 Register dst, Address src, Register tmp1, Register tmp_thread) {
450 bool on_oop = type == T_OBJECT || type == T_ARRAY;
451 bool in_heap = (decorators & IN_HEAP) != 0;
452 bool on_weak = (decorators & ON_WEAK_OOP_REF) != 0;
453 bool on_phantom = (decorators & ON_PHANTOM_OOP_REF) != 0;
454 bool on_reference = on_weak || on_phantom;
455 if (in_heap) {
456 read_barrier_not_null(masm, src.base());
457 }
458 BarrierSetAssembler::load_at(masm, decorators, type, dst, src, tmp1, tmp_thread);
459 if (ShenandoahKeepAliveBarrier && on_oop && on_reference) {
460 const Register thread = NOT_LP64(tmp_thread) LP64_ONLY(r15_thread);
461 NOT_LP64(__ get_thread(thread));
462
463 // Generate the SATB pre-barrier code to log the value of
464 // the referent field in an SATB buffer.
465 shenandoah_write_barrier_pre(masm /* masm */,
466 noreg /* obj */,
467 dst /* pre_val */,
468 thread /* thread */,
469 tmp1 /* tmp */,
470 true /* tosca_live */,
471 true /* expand_call */);
472 }
473 }
474
475 void ShenandoahBarrierSetAssembler::store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
476 Address dst, Register val, Register tmp1, Register tmp2) {
477
478 bool in_heap = (decorators & IN_HEAP) != 0;
479 bool as_normal = (decorators & AS_NORMAL) != 0;
480 if (in_heap) {
481 write_barrier(masm, dst.base());
482 }
483 if (type == T_OBJECT || type == T_ARRAY) {
484 bool needs_pre_barrier = as_normal;
485 bool needs_post_barrier = val != noreg && in_heap && UseShenandoahMatrix;
486
487 Register tmp3 = LP64_ONLY(r8) NOT_LP64(rsi);
488 Register rthread = LP64_ONLY(r15_thread) NOT_LP64(rcx);
489 // flatten object address if needed
490 // We do it regardless of precise because we need the registers
491 if (dst.index() == noreg && dst.disp() == 0) {
492 if (dst.base() != tmp1) {
493 __ movptr(tmp1, dst.base());
494 }
495 } else {
496 __ lea(tmp1, dst);
497 }
498
499 #ifndef _LP64
500 InterpreterMacroAssembler *imasm = static_cast<InterpreterMacroAssembler*>(masm);
501 #endif
502
503 NOT_LP64(__ get_thread(rcx));
504 NOT_LP64(imasm->save_bcp());
505
506 if (needs_pre_barrier) {
507 shenandoah_write_barrier_pre(masm /*masm*/,
508 tmp1 /* obj */,
509 tmp2 /* pre_val */,
510 rthread /* thread */,
511 tmp3 /* tmp */,
512 val != noreg /* tosca_live */,
513 false /* expand_call */);
514 }
515 if (val == noreg) {
516 BarrierSetAssembler::store_at(masm, decorators, type, Address(tmp1, 0), val, noreg, noreg);
517 } else {
518 storeval_barrier(masm, val, tmp3);
519 Register new_val = val;
520 if (needs_post_barrier) {
521 if (UseCompressedOops) {
522 new_val = tmp2;
523 __ movptr(new_val, val);
524 }
525 }
526 BarrierSetAssembler::store_at(masm, decorators, type, Address(tmp1, 0), val, noreg, noreg);
527
528 if (needs_post_barrier) {
529 shenandoah_write_barrier_post(masm /*masm*/,
530 tmp1 /* store_adr */,
531 new_val /* new_val */,
532 rthread /* thread */,
533 tmp3 /* tmp */,
534 tmp2 /* tmp2 */);
535 }
536 }
537 NOT_LP64(imasm->restore_bcp());
538
539 } else {
540 BarrierSetAssembler::store_at(masm, decorators, type, dst, val, tmp1, tmp2);
541 }
542 }
543
544 #ifndef _LP64
545 void ShenandoahBarrierSetAssembler::obj_equals(MacroAssembler* masm,
546 Address obj1, jobject obj2) {
547 Unimplemented();
548 }
549
550 void ShenandoahBarrierSetAssembler::obj_equals(MacroAssembler* masm,
551 Register obj1, jobject obj2) {
552 Unimplemented();
553 }
554 #endif
555
556
557 void ShenandoahBarrierSetAssembler::obj_equals(MacroAssembler* masm, Register op1, Register op2) {
558 __ cmpptr(op1, op2);
559 if (ShenandoahAcmpBarrier) {
560 Label done;
561 __ jccb(Assembler::equal, done);
562 read_barrier(masm, op1);
563 read_barrier(masm, op2);
564 __ cmpptr(op1, op2);
565 __ bind(done);
566 }
567 }
568
569 void ShenandoahBarrierSetAssembler::obj_equals(MacroAssembler* masm, Register src1, Address src2) {
570 __ cmpptr(src1, src2);
571 if (ShenandoahAcmpBarrier) {
572 Label done;
573 __ jccb(Assembler::equal, done);
574 __ movptr(rscratch2, src2);
575 read_barrier(masm, src1);
576 read_barrier(masm, rscratch2);
577 __ cmpptr(src1, rscratch2);
578 __ bind(done);
579 }
580 }
581
582 void ShenandoahBarrierSetAssembler::tlab_allocate(MacroAssembler* masm,
583 Register thread, Register obj,
584 Register var_size_in_bytes,
585 int con_size_in_bytes,
586 Register t1, Register t2,
587 Label& slow_case) {
588 assert_different_registers(obj, t1, t2);
589 assert_different_registers(obj, var_size_in_bytes, t1);
590 Register end = t2;
591 if (!thread->is_valid()) {
592 #ifdef _LP64
593 thread = r15_thread;
594 #else
595 assert(t1->is_valid(), "need temp reg");
596 thread = t1;
597 __ get_thread(thread);
598 #endif
599 }
600
601 __ verify_tlab();
602
603 __ movptr(obj, Address(thread, JavaThread::tlab_top_offset()));
604 if (var_size_in_bytes == noreg) {
605 __ lea(end, Address(obj, con_size_in_bytes + BrooksPointer::byte_size()));
606 } else {
607 __ addptr(var_size_in_bytes, BrooksPointer::byte_size());
608 __ lea(end, Address(obj, var_size_in_bytes, Address::times_1));
609 }
610 __ cmpptr(end, Address(thread, JavaThread::tlab_end_offset()));
611 __ jcc(Assembler::above, slow_case);
612
613 // update the tlab top pointer
614 __ movptr(Address(thread, JavaThread::tlab_top_offset()), end);
615
616 // Initialize brooks pointer
617 #ifdef _LP64
618 __ incrementq(obj, BrooksPointer::byte_size());
619 #else
620 __ incrementl(obj, BrooksPointer::byte_size());
621 #endif
622 __ movptr(Address(obj, BrooksPointer::byte_offset()), obj);
623
624 // recover var_size_in_bytes if necessary
625 if (var_size_in_bytes == end) {
626 __ subptr(var_size_in_bytes, obj);
627 }
628 __ verify_tlab();
629 }
630
631 void ShenandoahBarrierSetAssembler::resolve_for_read(MacroAssembler* masm, DecoratorSet decorators, Register obj) {
632 bool oop_not_null = (decorators & IS_NOT_NULL) != 0;
633 if (oop_not_null) {
634 read_barrier_not_null(masm, obj);
635 } else {
636 read_barrier(masm, obj);
637 }
638 }
639
640 void ShenandoahBarrierSetAssembler::resolve_for_write(MacroAssembler* masm, DecoratorSet decorators, Register obj) {
641 bool oop_not_null = (decorators & IS_NOT_NULL) != 0;
642 if (oop_not_null) {
643 write_barrier(masm, obj);
644 } else {
645 Label done;
646 __ testptr(obj, obj);
647 __ jcc(Assembler::zero, done);
648 write_barrier(masm, obj);
649 __ bind(done);
650 }
651 }
652
653 // Special Shenandoah CAS implementation that handles false negatives
654 // due to concurrent evacuation.
655 #ifndef _LP64
656 void ShenandoahBarrierSetAssembler::cmpxchg_oop(MacroAssembler* masm, DecoratorSet decorators,
657 Register res, Address addr, Register oldval, Register newval,
658 bool exchange, bool encode, Register tmp1, Register tmp2) {
659 // Shenandoah has no 32-bit version for this.
660 Unimplemented();
661 }
662 #else
663 void ShenandoahBarrierSetAssembler::cmpxchg_oop(MacroAssembler* masm, DecoratorSet decorators,
664 Register res, Address addr, Register oldval, Register newval,
665 bool exchange, bool encode, Register tmp1, Register tmp2) {
666
667 if (!ShenandoahCASBarrier) {
668 BarrierSetAssembler::cmpxchg_oop(masm, decorators, res, addr, oldval, newval, exchange, encode, tmp1, tmp2);
669 return;
670 }
671
672 assert(ShenandoahCASBarrier, "Should only be used when CAS barrier is enabled");
673 assert(oldval == rax, "must be in rax for implicit use in cmpxchg");
674
675 Label retry, done;
676
677 // Apply storeval barrier to newval.
678 if (encode) {
679 storeval_barrier(masm, newval, tmp1);
680 }
681
682 if (UseCompressedOops) {
683 if (encode) {
684 __ encode_heap_oop(oldval);
685 __ mov(rscratch1, newval);
686 __ encode_heap_oop(rscratch1);
687 newval = rscratch1;
688 }
689 }
690
691 // Remember oldval for retry logic below
692 if (UseCompressedOops) {
693 __ movl(tmp1, oldval);
694 } else {
695 __ movptr(tmp1, oldval);
696 }
697
698 // Step 1. Try to CAS with given arguments. If successful, then we are done,
699 // and can safely return.
700 if (os::is_MP()) __ lock();
701 if (UseCompressedOops) {
702 __ cmpxchgl(newval, addr);
703 } else {
704 __ cmpxchgptr(newval, addr);
705 }
706 __ jcc(Assembler::equal, done, true);
707
708 // Step 2. CAS had failed. This may be a false negative.
709 //
710 // The trouble comes when we compare the to-space pointer with the from-space
711 // pointer to the same object. To resolve this, it will suffice to read both
712 // oldval and the value from memory through the read barriers -- this will give
713 // both to-space pointers. If they mismatch, then it was a legitimate failure.
714 //
715 if (UseCompressedOops) {
716 __ decode_heap_oop(tmp1);
717 }
718 __ resolve_for_read(0, tmp1);
719
720 if (UseCompressedOops) {
721 __ movl(tmp2, oldval);
722 __ decode_heap_oop(tmp2);
723 } else {
724 __ movptr(tmp2, oldval);
725 }
726 __ resolve_for_read(0, tmp2);
727
728 __ cmpptr(tmp1, tmp2);
729 __ jcc(Assembler::notEqual, done, true);
730
731 // Step 3. Try to CAS again with resolved to-space pointers.
732 //
733 // Corner case: it may happen that somebody stored the from-space pointer
734 // to memory while we were preparing for retry. Therefore, we can fail again
735 // on retry, and so need to do this in loop, always re-reading the failure
736 // witness through the read barrier.
737 __ bind(retry);
738 if (os::is_MP()) __ lock();
739 if (UseCompressedOops) {
740 __ cmpxchgl(newval, addr);
741 } else {
742 __ cmpxchgptr(newval, addr);
743 }
744 __ jcc(Assembler::equal, done, true);
745
746 if (UseCompressedOops) {
747 __ movl(tmp2, oldval);
748 __ decode_heap_oop(tmp2);
749 } else {
750 __ movptr(tmp2, oldval);
751 }
752 __ resolve_for_read(0, tmp2);
753
754 __ cmpptr(tmp1, tmp2);
755 __ jcc(Assembler::equal, retry, true);
756
757 // Step 4. If we need a boolean result out of CAS, check the flag again,
758 // and promote the result. Note that we handle the flag from both the CAS
759 // itself and from the retry loop.
760 __ bind(done);
761 if (!exchange) {
762 assert(res != NULL, "need result register");
763 __ setb(Assembler::equal, res);
764 __ movzbl(res, res);
765 }
766 }
767 #endif // LP64
768
769 void ShenandoahBarrierSetAssembler::xchg_oop(MacroAssembler* masm, DecoratorSet decorators,
770 Register obj, Address addr, Register tmp) {
771 storeval_barrier(masm, obj, tmp);
772 BarrierSetAssembler::xchg_oop(masm, decorators, obj, addr, tmp);
773 }
774
775 #ifdef COMPILER1
776
777 #undef __
778 #define __ ce->masm()->
779
780 void ShenandoahBarrierSetAssembler::gen_pre_barrier_stub(LIR_Assembler* ce, ShenandoahPreBarrierStub* stub) {
781 ShenandoahBarrierSetC1* bs = (ShenandoahBarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1();
782 // At this point we know that marking is in progress.
783 // If do_load() is true then we have to emit the
784 // load of the previous value; otherwise it has already
785 // been loaded into _pre_val.
786
787 __ bind(*stub->entry());
788 assert(stub->pre_val()->is_register(), "Precondition.");
789
790 Register pre_val_reg = stub->pre_val()->as_register();
791
792 if (stub->do_load()) {
793 ce->mem2reg(stub->addr(), stub->pre_val(), T_OBJECT, stub->patch_code(), stub->info(), false /*wide*/, false /*unaligned*/);
794 }
795
796 __ cmpptr(pre_val_reg, (int32_t)NULL_WORD);
797 __ jcc(Assembler::equal, *stub->continuation());
798 ce->store_parameter(stub->pre_val()->as_register(), 0);
799 __ call(RuntimeAddress(bs->pre_barrier_c1_runtime_code_blob()->code_begin()));
800 __ jmp(*stub->continuation());
801
802 }
803
804 void ShenandoahBarrierSetAssembler::gen_write_barrier_stub(LIR_Assembler* ce, ShenandoahWriteBarrierStub* stub) {
805 __ bind(*stub->entry());
806
807 Label done;
808 Register obj = stub->obj()->as_register();
809 Register res = stub->result()->as_register();
810
811 if (res != obj) {
812 __ mov(res, obj);
813 }
814
815 // Check for null.
816 if (stub->needs_null_check()) {
817 __ testptr(res, res);
818 __ jcc(Assembler::zero, done);
819 }
820
821 write_barrier(ce->masm(), res);
822
823 __ bind(done);
824 __ jmp(*stub->continuation());
825 }
826
827 #undef __
828
829 #define __ sasm->
830
831 void ShenandoahBarrierSetAssembler::generate_c1_pre_barrier_runtime_stub(StubAssembler* sasm) {
832 __ prologue("shenandoah_pre_barrier", false);
833 // arg0 : previous value of memory
834
835 __ push(rax);
836 __ push(rdx);
837
838 const Register pre_val = rax;
839 const Register thread = NOT_LP64(rax) LP64_ONLY(r15_thread);
840 const Register tmp = rdx;
841
842 NOT_LP64(__ get_thread(thread);)
843
844 Address queue_index(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_index_offset()));
845 Address buffer(thread, in_bytes(ShenandoahThreadLocalData::satb_mark_queue_buffer_offset()));
846
847 Label done;
848 Label runtime;
849
850 // Is SATB still active?
851 Address gc_state(thread, in_bytes(ShenandoahThreadLocalData::gc_state_offset()));
852 __ testb(gc_state, ShenandoahHeap::MARKING | ShenandoahHeap::TRAVERSAL);
853 __ jcc(Assembler::zero, done);
854
855 // Can we store original value in the thread's buffer?
856
857 __ movptr(tmp, queue_index);
858 __ testptr(tmp, tmp);
859 __ jcc(Assembler::zero, runtime);
860 __ subptr(tmp, wordSize);
861 __ movptr(queue_index, tmp);
862 __ addptr(tmp, buffer);
863
864 // prev_val (rax)
865 __ load_parameter(0, pre_val);
866 __ movptr(Address(tmp, 0), pre_val);
867 __ jmp(done);
868
869 __ bind(runtime);
870
871 __ save_live_registers_no_oop_map(true);
872
873 // load the pre-value
874 __ load_parameter(0, rcx);
875 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_ref_field_pre_entry), rcx, thread);
876
877 __ restore_live_registers(true);
878
879 __ bind(done);
880
881 __ pop(rdx);
882 __ pop(rax);
883
884 __ epilogue();
885 }
886
887 #undef __
888
889 #endif // COMPILER1
890
891 address ShenandoahBarrierSetAssembler::shenandoah_wb() {
892 assert(_shenandoah_wb != NULL, "need write barrier stub");
893 return _shenandoah_wb;
894 }
895
896 address ShenandoahBarrierSetAssembler::shenandoah_wb_C() {
897 assert(_shenandoah_wb_C != NULL, "need write barrier stub");
898 return _shenandoah_wb_C;
899 }
900
901 #define __ cgen->assembler()->
902
903 address ShenandoahBarrierSetAssembler::generate_shenandoah_wb(StubCodeGenerator* cgen, bool c_abi, bool do_cset_test) {
904 __ align(CodeEntryAlignment);
905 StubCodeMark mark(cgen, "StubRoutines", "shenandoah_wb");
906 address start = __ pc();
907
908 #ifdef _LP64
909 Label not_done;
910
911 // We use RDI, which also serves as argument register for slow call.
912 // RAX always holds the src object ptr, except after the slow call and
913 // the cmpxchg, then it holds the result.
914 // R8 and RCX are used as temporary registers.
915 if (!c_abi) {
916 __ push(rdi);
917 __ push(r8);
918 }
919
920 // Check for object beeing in the collection set.
921 // TODO: Can we use only 1 register here?
922 // The source object arrives here in rax.
923 // live: rax
924 // live: rdi
925 if (!c_abi) {
926 __ mov(rdi, rax);
927 } else {
928 if (rax != c_rarg0) {
929 __ mov(rax, c_rarg0);
930 }
931 }
932 if (do_cset_test) {
933 __ shrptr(rdi, ShenandoahHeapRegion::region_size_bytes_shift_jint());
934 // live: r8
935 __ movptr(r8, (intptr_t) ShenandoahHeap::in_cset_fast_test_addr());
936 __ movbool(r8, Address(r8, rdi, Address::times_1));
937 // unlive: rdi
938 __ testbool(r8);
939 // unlive: r8
940 __ jccb(Assembler::notZero, not_done);
941
942 if (!c_abi) {
943 __ pop(r8);
944 __ pop(rdi);
945 }
946 __ ret(0);
947
948 __ bind(not_done);
949 }
950
951 if (!c_abi) {
952 __ push(rcx);
953 }
954
955 if (!c_abi) {
956 __ push(rdx);
957 __ push(rdi);
958 __ push(rsi);
959 __ push(r8);
960 __ push(r9);
961 __ push(r10);
962 __ push(r11);
963 __ push(r12);
964 __ push(r13);
965 __ push(r14);
966 __ push(r15);
967 }
968 __ save_vector_registers();
969 __ movptr(rdi, rax);
970 __ call_VM_leaf(CAST_FROM_FN_PTR(address, ShenandoahRuntime::write_barrier_JRT), rdi);
971 __ restore_vector_registers();
972 if (!c_abi) {
973 __ pop(r15);
974 __ pop(r14);
975 __ pop(r13);
976 __ pop(r12);
977 __ pop(r11);
978 __ pop(r10);
979 __ pop(r9);
980 __ pop(r8);
981 __ pop(rsi);
982 __ pop(rdi);
983 __ pop(rdx);
984
985 __ pop(rcx);
986 __ pop(r8);
987 __ pop(rdi);
988 }
989 __ ret(0);
990 #else
991 ShouldNotReachHere();
992 #endif
993 return start;
994 }
995
996 #undef __
997
998 void ShenandoahBarrierSetAssembler::barrier_stubs_init() {
999 if (ShenandoahWriteBarrier || ShenandoahStoreValEnqueueBarrier) {
1000 int stub_code_size = 4096;
1001 ResourceMark rm;
1002 BufferBlob* bb = BufferBlob::create("shenandoah_barrier_stubs", stub_code_size);
1003 CodeBuffer buf(bb);
1004 StubCodeGenerator cgen(&buf);
1005 _shenandoah_wb = generate_shenandoah_wb(&cgen, false, true);
1006 _shenandoah_wb_C = generate_shenandoah_wb(&cgen, true, !ShenandoahWriteBarrierCsetTestInIR);
1007 }
1008 }