1 /*
2 * Copyright (c) 2018, 2019, 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/g1ThreadLocalData.hpp"
32 #include "gc/g1/heapRegion.hpp"
33 #include "gc/shared/collectedHeap.hpp"
34 #include "runtime/sharedRuntime.hpp"
35 #include "runtime/thread.hpp"
36 #include "interpreter/interp_masm.hpp"
37 #include "runtime/sharedRuntime.hpp"
38 #ifdef COMPILER1
39 #include "c1/c1_LIRAssembler.hpp"
40 #include "c1/c1_MacroAssembler.hpp"
41 #include "gc/g1/c1/g1BarrierSetC1.hpp"
42 #endif
43
44 #define __ masm->
45
gen_write_ref_array_pre_barrier(MacroAssembler * masm,DecoratorSet decorators,Register addr,Register count,RegSet saved_regs)46 void G1BarrierSetAssembler::gen_write_ref_array_pre_barrier(MacroAssembler* masm, DecoratorSet decorators,
47 Register addr, Register count, RegSet saved_regs) {
48 bool dest_uninitialized = (decorators & IS_DEST_UNINITIALIZED) != 0;
49 if (!dest_uninitialized) {
50 __ push(saved_regs, sp);
51 if (count == c_rarg0) {
52 if (addr == c_rarg1) {
53 // exactly backwards!!
54 __ mov(rscratch1, c_rarg0);
55 __ mov(c_rarg0, c_rarg1);
56 __ mov(c_rarg1, rscratch1);
57 } else {
58 __ mov(c_rarg1, count);
59 __ mov(c_rarg0, addr);
60 }
61 } else {
62 __ mov(c_rarg0, addr);
63 __ mov(c_rarg1, count);
64 }
65 if (UseCompressedOops) {
66 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_array_pre_narrow_oop_entry), 2);
67 } else {
68 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_array_pre_oop_entry), 2);
69 }
70 __ pop(saved_regs, sp);
71 }
72 }
73
gen_write_ref_array_post_barrier(MacroAssembler * masm,DecoratorSet decorators,Register start,Register count,Register scratch,RegSet saved_regs)74 void G1BarrierSetAssembler::gen_write_ref_array_post_barrier(MacroAssembler* masm, DecoratorSet decorators,
75 Register start, Register count, Register scratch, RegSet saved_regs) {
76 __ push(saved_regs, sp);
77 assert_different_registers(start, count, scratch);
78 assert_different_registers(c_rarg0, count);
79 __ mov(c_rarg0, start);
80 __ mov(c_rarg1, count);
81 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_array_post_entry), 2);
82 __ pop(saved_regs, sp);
83 }
84
g1_write_barrier_pre(MacroAssembler * masm,Register obj,Register pre_val,Register thread,Register tmp,bool tosca_live,bool expand_call)85 void G1BarrierSetAssembler::g1_write_barrier_pre(MacroAssembler* masm,
86 Register obj,
87 Register pre_val,
88 Register thread,
89 Register tmp,
90 bool tosca_live,
91 bool expand_call) {
92 // If expand_call is true then we expand the call_VM_leaf macro
93 // directly to skip generating the check by
94 // InterpreterMacroAssembler::call_VM_leaf_base that checks _last_sp.
95
96 assert(thread == rthread, "must be");
97
98 Label done;
99 Label runtime;
100
101 assert_different_registers(obj, pre_val, tmp, rscratch1);
102 assert(pre_val != noreg && tmp != noreg, "expecting a register");
103
104 Address in_progress(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_active_offset()));
105 Address index(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_index_offset()));
106 Address buffer(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_buffer_offset()));
107
108 // Is marking active?
109 if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) {
110 __ ldrw(tmp, in_progress);
111 } else {
112 assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "Assumption");
113 __ ldrb(tmp, in_progress);
114 }
115 __ cbzw(tmp, done);
116
117 // Do we need to load the previous value?
118 if (obj != noreg) {
119 __ load_heap_oop(pre_val, Address(obj, 0), noreg, noreg, AS_RAW);
120 }
121
122 // Is the previous value null?
123 __ cbz(pre_val, done);
124
125 // Can we store original value in the thread's buffer?
126 // Is index == 0?
127 // (The index field is typed as size_t.)
128
129 __ ldr(tmp, index); // tmp := *index_adr
130 __ cbz(tmp, runtime); // tmp == 0?
131 // If yes, goto runtime
132
133 __ sub(tmp, tmp, wordSize); // tmp := tmp - wordSize
134 __ str(tmp, index); // *index_adr := tmp
135 __ ldr(rscratch1, buffer);
136 __ add(tmp, tmp, rscratch1); // tmp := tmp + *buffer_adr
137
138 // Record the previous value
139 __ str(pre_val, Address(tmp, 0));
140 __ b(done);
141
142 __ bind(runtime);
143 // save the live input values
144 RegSet saved = RegSet::of(pre_val);
145 if (tosca_live) saved += RegSet::of(r0);
146 if (obj != noreg) saved += RegSet::of(obj);
147
148 __ push(saved, sp);
149
150 // Calling the runtime using the regular call_VM_leaf mechanism generates
151 // code (generated by InterpreterMacroAssember::call_VM_leaf_base)
152 // that checks that the *(rfp+frame::interpreter_frame_last_sp) == NULL.
153 //
154 // If we care generating the pre-barrier without a frame (e.g. in the
155 // intrinsified Reference.get() routine) then ebp might be pointing to
156 // the caller frame and so this check will most likely fail at runtime.
157 //
158 // Expanding the call directly bypasses the generation of the check.
159 // So when we do not have have a full interpreter frame on the stack
160 // expand_call should be passed true.
161
162 if (expand_call) {
163 assert(pre_val != c_rarg1, "smashed arg");
164 __ super_call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_pre_entry), pre_val, thread);
165 } else {
166 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_pre_entry), pre_val, thread);
167 }
168
169 __ pop(saved, sp);
170
171 __ bind(done);
172
173 }
174
g1_write_barrier_post(MacroAssembler * masm,Register store_addr,Register new_val,Register thread,Register tmp,Register tmp2)175 void G1BarrierSetAssembler::g1_write_barrier_post(MacroAssembler* masm,
176 Register store_addr,
177 Register new_val,
178 Register thread,
179 Register tmp,
180 Register tmp2) {
181 assert(thread == rthread, "must be");
182 assert_different_registers(store_addr, new_val, thread, tmp, tmp2,
183 rscratch1);
184 assert(store_addr != noreg && new_val != noreg && tmp != noreg
185 && tmp2 != noreg, "expecting a register");
186
187 Address queue_index(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_index_offset()));
188 Address buffer(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_buffer_offset()));
189
190 BarrierSet* bs = BarrierSet::barrier_set();
191 CardTableBarrierSet* ctbs = barrier_set_cast<CardTableBarrierSet>(bs);
192 CardTable* ct = ctbs->card_table();
193
194 Label done;
195 Label runtime;
196
197 // Does store cross heap regions?
198
199 __ eor(tmp, store_addr, new_val);
200 __ lsr(tmp, tmp, HeapRegion::LogOfHRGrainBytes);
201 __ cbz(tmp, done);
202
203 // crosses regions, storing NULL?
204
205 __ cbz(new_val, done);
206
207 // storing region crossing non-NULL, is card already dirty?
208
209 ExternalAddress cardtable((address) ct->byte_map_base());
210 const Register card_addr = tmp;
211
212 __ lsr(card_addr, store_addr, CardTable::card_shift);
213
214 // get the address of the card
215 __ load_byte_map_base(tmp2);
216 __ add(card_addr, card_addr, tmp2);
217 __ ldrb(tmp2, Address(card_addr));
218 __ cmpw(tmp2, (int)G1CardTable::g1_young_card_val());
219 __ br(Assembler::EQ, done);
220
221 assert((int)CardTable::dirty_card_val() == 0, "must be 0");
222
223 __ membar(Assembler::StoreLoad);
224
225 __ ldrb(tmp2, Address(card_addr));
226 __ cbzw(tmp2, done);
227
228 // storing a region crossing, non-NULL oop, card is clean.
229 // dirty card and log.
230
231 __ strb(zr, Address(card_addr));
232
233 __ ldr(rscratch1, queue_index);
234 __ cbz(rscratch1, runtime);
235 __ sub(rscratch1, rscratch1, wordSize);
236 __ str(rscratch1, queue_index);
237
238 __ ldr(tmp2, buffer);
239 __ str(card_addr, Address(tmp2, rscratch1));
240 __ b(done);
241
242 __ bind(runtime);
243 // save the live input values
244 RegSet saved = RegSet::of(store_addr, new_val);
245 __ push(saved, sp);
246 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_post_entry), card_addr, thread);
247 __ pop(saved, sp);
248
249 __ bind(done);
250 }
251
load_at(MacroAssembler * masm,DecoratorSet decorators,BasicType type,Register dst,Address src,Register tmp1,Register tmp_thread)252 void G1BarrierSetAssembler::load_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
253 Register dst, Address src, Register tmp1, Register tmp_thread) {
254 bool on_oop = is_reference_type(type);
255 bool on_weak = (decorators & ON_WEAK_OOP_REF) != 0;
256 bool on_phantom = (decorators & ON_PHANTOM_OOP_REF) != 0;
257 bool on_reference = on_weak || on_phantom;
258 ModRefBarrierSetAssembler::load_at(masm, decorators, type, dst, src, tmp1, tmp_thread);
259 if (on_oop && on_reference) {
260 // LR is live. It must be saved around calls.
261 __ enter(); // barrier may call runtime
262 // Generate the G1 pre-barrier code to log the value of
263 // the referent field in an SATB buffer.
264 g1_write_barrier_pre(masm /* masm */,
265 noreg /* obj */,
266 dst /* pre_val */,
267 rthread /* thread */,
268 tmp1 /* tmp */,
269 true /* tosca_live */,
270 true /* expand_call */);
271 __ leave();
272 }
273 }
274
oop_store_at(MacroAssembler * masm,DecoratorSet decorators,BasicType type,Address dst,Register val,Register tmp1,Register tmp2)275 void G1BarrierSetAssembler::oop_store_at(MacroAssembler* masm, DecoratorSet decorators, BasicType type,
276 Address dst, Register val, Register tmp1, Register tmp2) {
277 // flatten object address if needed
278 if (dst.index() == noreg && dst.offset() == 0) {
279 if (dst.base() != r3) {
280 __ mov(r3, dst.base());
281 }
282 } else {
283 __ lea(r3, dst);
284 }
285
286 g1_write_barrier_pre(masm,
287 r3 /* obj */,
288 tmp2 /* pre_val */,
289 rthread /* thread */,
290 tmp1 /* tmp */,
291 val != noreg /* tosca_live */,
292 false /* expand_call */);
293
294 if (val == noreg) {
295 BarrierSetAssembler::store_at(masm, decorators, type, Address(r3, 0), noreg, noreg, noreg);
296 } else {
297 // G1 barrier needs uncompressed oop for region cross check.
298 Register new_val = val;
299 if (UseCompressedOops) {
300 new_val = rscratch2;
301 __ mov(new_val, val);
302 }
303 BarrierSetAssembler::store_at(masm, decorators, type, Address(r3, 0), val, noreg, noreg);
304 g1_write_barrier_post(masm,
305 r3 /* store_adr */,
306 new_val /* new_val */,
307 rthread /* thread */,
308 tmp1 /* tmp */,
309 tmp2 /* tmp2 */);
310 }
311
312 }
313
314 #ifdef COMPILER1
315
316 #undef __
317 #define __ ce->masm()->
318
gen_pre_barrier_stub(LIR_Assembler * ce,G1PreBarrierStub * stub)319 void G1BarrierSetAssembler::gen_pre_barrier_stub(LIR_Assembler* ce, G1PreBarrierStub* stub) {
320 G1BarrierSetC1* bs = (G1BarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1();
321 // At this point we know that marking is in progress.
322 // If do_load() is true then we have to emit the
323 // load of the previous value; otherwise it has already
324 // been loaded into _pre_val.
325
326 __ bind(*stub->entry());
327
328 assert(stub->pre_val()->is_register(), "Precondition.");
329
330 Register pre_val_reg = stub->pre_val()->as_register();
331
332 if (stub->do_load()) {
333 ce->mem2reg(stub->addr(), stub->pre_val(), T_OBJECT, stub->patch_code(), stub->info(), false /*wide*/, false /*unaligned*/);
334 }
335 __ cbz(pre_val_reg, *stub->continuation());
336 ce->store_parameter(stub->pre_val()->as_register(), 0);
337 __ far_call(RuntimeAddress(bs->pre_barrier_c1_runtime_code_blob()->code_begin()));
338 __ b(*stub->continuation());
339 }
340
gen_post_barrier_stub(LIR_Assembler * ce,G1PostBarrierStub * stub)341 void G1BarrierSetAssembler::gen_post_barrier_stub(LIR_Assembler* ce, G1PostBarrierStub* stub) {
342 G1BarrierSetC1* bs = (G1BarrierSetC1*)BarrierSet::barrier_set()->barrier_set_c1();
343 __ bind(*stub->entry());
344 assert(stub->addr()->is_register(), "Precondition.");
345 assert(stub->new_val()->is_register(), "Precondition.");
346 Register new_val_reg = stub->new_val()->as_register();
347 __ cbz(new_val_reg, *stub->continuation());
348 ce->store_parameter(stub->addr()->as_pointer_register(), 0);
349 __ far_call(RuntimeAddress(bs->post_barrier_c1_runtime_code_blob()->code_begin()));
350 __ b(*stub->continuation());
351 }
352
353 #undef __
354
355 #define __ sasm->
356
generate_c1_pre_barrier_runtime_stub(StubAssembler * sasm)357 void G1BarrierSetAssembler::generate_c1_pre_barrier_runtime_stub(StubAssembler* sasm) {
358 __ prologue("g1_pre_barrier", false);
359
360 // arg0 : previous value of memory
361
362 BarrierSet* bs = BarrierSet::barrier_set();
363
364 const Register pre_val = r0;
365 const Register thread = rthread;
366 const Register tmp = rscratch1;
367
368 Address in_progress(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_active_offset()));
369 Address queue_index(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_index_offset()));
370 Address buffer(thread, in_bytes(G1ThreadLocalData::satb_mark_queue_buffer_offset()));
371
372 Label done;
373 Label runtime;
374
375 // Is marking still active?
376 if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) {
377 __ ldrw(tmp, in_progress);
378 } else {
379 assert(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1, "Assumption");
380 __ ldrb(tmp, in_progress);
381 }
382 __ cbzw(tmp, done);
383
384 // Can we store original value in the thread's buffer?
385 __ ldr(tmp, queue_index);
386 __ cbz(tmp, runtime);
387
388 __ sub(tmp, tmp, wordSize);
389 __ str(tmp, queue_index);
390 __ ldr(rscratch2, buffer);
391 __ add(tmp, tmp, rscratch2);
392 __ load_parameter(0, rscratch2);
393 __ str(rscratch2, Address(tmp, 0));
394 __ b(done);
395
396 __ bind(runtime);
397 __ push_call_clobbered_registers();
398 __ load_parameter(0, pre_val);
399 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_pre_entry), pre_val, thread);
400 __ pop_call_clobbered_registers();
401 __ bind(done);
402
403 __ epilogue();
404 }
405
generate_c1_post_barrier_runtime_stub(StubAssembler * sasm)406 void G1BarrierSetAssembler::generate_c1_post_barrier_runtime_stub(StubAssembler* sasm) {
407 __ prologue("g1_post_barrier", false);
408
409 // arg0: store_address
410 Address store_addr(rfp, 2*BytesPerWord);
411
412 BarrierSet* bs = BarrierSet::barrier_set();
413 CardTableBarrierSet* ctbs = barrier_set_cast<CardTableBarrierSet>(bs);
414 CardTable* ct = ctbs->card_table();
415
416 Label done;
417 Label runtime;
418
419 // At this point we know new_value is non-NULL and the new_value crosses regions.
420 // Must check to see if card is already dirty
421
422 const Register thread = rthread;
423
424 Address queue_index(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_index_offset()));
425 Address buffer(thread, in_bytes(G1ThreadLocalData::dirty_card_queue_buffer_offset()));
426
427 const Register card_offset = rscratch2;
428 // LR is free here, so we can use it to hold the byte_map_base.
429 const Register byte_map_base = lr;
430
431 assert_different_registers(card_offset, byte_map_base, rscratch1);
432
433 __ load_parameter(0, card_offset);
434 __ lsr(card_offset, card_offset, CardTable::card_shift);
435 __ load_byte_map_base(byte_map_base);
436 __ ldrb(rscratch1, Address(byte_map_base, card_offset));
437 __ cmpw(rscratch1, (int)G1CardTable::g1_young_card_val());
438 __ br(Assembler::EQ, done);
439
440 assert((int)CardTable::dirty_card_val() == 0, "must be 0");
441
442 __ membar(Assembler::StoreLoad);
443 __ ldrb(rscratch1, Address(byte_map_base, card_offset));
444 __ cbzw(rscratch1, done);
445
446 // storing region crossing non-NULL, card is clean.
447 // dirty card and log.
448 __ strb(zr, Address(byte_map_base, card_offset));
449
450 // Convert card offset into an address in card_addr
451 Register card_addr = card_offset;
452 __ add(card_addr, byte_map_base, card_addr);
453
454 __ ldr(rscratch1, queue_index);
455 __ cbz(rscratch1, runtime);
456 __ sub(rscratch1, rscratch1, wordSize);
457 __ str(rscratch1, queue_index);
458
459 // Reuse LR to hold buffer_addr
460 const Register buffer_addr = lr;
461
462 __ ldr(buffer_addr, buffer);
463 __ str(card_addr, Address(buffer_addr, rscratch1));
464 __ b(done);
465
466 __ bind(runtime);
467 __ push_call_clobbered_registers();
468 __ call_VM_leaf(CAST_FROM_FN_PTR(address, G1BarrierSetRuntime::write_ref_field_post_entry), card_addr, thread);
469 __ pop_call_clobbered_registers();
470 __ bind(done);
471 __ epilogue();
472 }
473
474 #undef __
475
476 #endif // COMPILER1
477