1 /*
2 * Copyright (c) 2018, Red Hat, Inc. All rights reserved.
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 "c1/c1_IR.hpp"
26 #include "gc/shared/satbMarkQueue.hpp"
27 #include "gc/shenandoah/shenandoahBarrierSetAssembler.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 "gc/shenandoah/c1/shenandoahBarrierSetC1.hpp"
33
34 #ifdef ASSERT
35 #define __ gen->lir(__FILE__, __LINE__)->
36 #else
37 #define __ gen->lir()->
38 #endif
39
40 void ShenandoahPreBarrierStub::emit_code(LIR_Assembler* ce) {
41 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
42 bs->gen_pre_barrier_stub(ce, this);
43 }
44
45 void ShenandoahLoadReferenceBarrierStub::emit_code(LIR_Assembler* ce) {
46 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
47 bs->gen_load_reference_barrier_stub(ce, this);
48 }
49
50 ShenandoahBarrierSetC1::ShenandoahBarrierSetC1() :
51 _pre_barrier_c1_runtime_code_blob(NULL),
52 _load_reference_barrier_rt_code_blob(NULL) {}
53
54 void ShenandoahBarrierSetC1::pre_barrier(LIRGenerator* gen, CodeEmitInfo* info, DecoratorSet decorators, LIR_Opr addr_opr, LIR_Opr pre_val) {
55 // First we test whether marking is in progress.
56 BasicType flag_type;
57 bool patch = (decorators & C1_NEEDS_PATCHING) != 0;
58 bool do_load = pre_val == LIR_OprFact::illegalOpr;
59 if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) {
60 flag_type = T_INT;
61 } else {
62 guarantee(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1,
63 "Assumption");
64 // Use unsigned type T_BOOLEAN here rather than signed T_BYTE since some platforms, eg. ARM,
65 // need to use unsigned instructions to use the large offset to load the satb_mark_queue.
66 flag_type = T_BOOLEAN;
67 }
68 LIR_Opr thrd = gen->getThreadPointer();
69 LIR_Address* mark_active_flag_addr =
70 new LIR_Address(thrd,
71 in_bytes(ShenandoahThreadLocalData::satb_mark_queue_active_offset()),
72 flag_type);
73 // Read the marking-in-progress flag.
74 LIR_Opr flag_val = gen->new_register(T_INT);
75 __ load(mark_active_flag_addr, flag_val);
76 __ cmp(lir_cond_notEqual, flag_val, LIR_OprFact::intConst(0));
77
78 LIR_PatchCode pre_val_patch_code = lir_patch_none;
79
80 CodeStub* slow;
81
82 if (do_load) {
83 assert(pre_val == LIR_OprFact::illegalOpr, "sanity");
84 assert(addr_opr != LIR_OprFact::illegalOpr, "sanity");
85
86 if (patch)
87 pre_val_patch_code = lir_patch_normal;
88
89 pre_val = gen->new_register(T_OBJECT);
90
91 if (!addr_opr->is_address()) {
92 assert(addr_opr->is_register(), "must be");
93 addr_opr = LIR_OprFact::address(new LIR_Address(addr_opr, T_OBJECT));
94 }
95 slow = new ShenandoahPreBarrierStub(addr_opr, pre_val, pre_val_patch_code, info ? new CodeEmitInfo(info) : NULL);
96 } else {
97 assert(addr_opr == LIR_OprFact::illegalOpr, "sanity");
98 assert(pre_val->is_register(), "must be");
99 assert(pre_val->type() == T_OBJECT, "must be an object");
100
101 slow = new ShenandoahPreBarrierStub(pre_val);
102 }
103
104 __ branch(lir_cond_notEqual, T_INT, slow);
105 __ branch_destination(slow->continuation());
106 }
107
108 LIR_Opr ShenandoahBarrierSetC1::load_reference_barrier(LIRGenerator* gen, LIR_Opr obj, LIR_Opr addr) {
109 if (ShenandoahLoadRefBarrier) {
110 return load_reference_barrier_impl(gen, obj, addr);
111 } else {
112 return obj;
113 }
114 }
115
116 LIR_Opr ShenandoahBarrierSetC1::load_reference_barrier_impl(LIRGenerator* gen, LIR_Opr obj, LIR_Opr addr) {
117 assert(ShenandoahLoadRefBarrier, "Should be enabled");
118
119 obj = ensure_in_register(gen, obj);
120 assert(obj->is_register(), "must be a register at this point");
121 addr = ensure_in_register(gen, addr);
122 assert(addr->is_register(), "must be a register at this point");
123 LIR_Opr result = gen->result_register_for(obj->value_type());
124 __ move(obj, result);
125 LIR_Opr tmp1 = gen->new_register(T_OBJECT);
126 LIR_Opr tmp2 = gen->new_register(T_OBJECT);
127
128 LIR_Opr thrd = gen->getThreadPointer();
129 LIR_Address* active_flag_addr =
130 new LIR_Address(thrd,
131 in_bytes(ShenandoahThreadLocalData::gc_state_offset()),
132 T_BYTE);
133 // Read and check the gc-state-flag.
134 LIR_Opr flag_val = gen->new_register(T_INT);
135 __ load(active_flag_addr, flag_val);
136 LIR_Opr mask = LIR_OprFact::intConst(ShenandoahHeap::HAS_FORWARDED |
137 ShenandoahHeap::EVACUATION |
138 ShenandoahHeap::TRAVERSAL);
139 LIR_Opr mask_reg = gen->new_register(T_INT);
140 __ move(mask, mask_reg);
141
142 if (TwoOperandLIRForm) {
143 __ logical_and(flag_val, mask_reg, flag_val);
144 } else {
145 LIR_Opr masked_flag = gen->new_register(T_INT);
146 __ logical_and(flag_val, mask_reg, masked_flag);
147 flag_val = masked_flag;
148 }
149 __ cmp(lir_cond_notEqual, flag_val, LIR_OprFact::intConst(0));
150
151 CodeStub* slow = new ShenandoahLoadReferenceBarrierStub(obj, addr, result, tmp1, tmp2);
152 __ branch(lir_cond_notEqual, T_INT, slow);
153 __ branch_destination(slow->continuation());
154
155 return result;
156 }
157
158 LIR_Opr ShenandoahBarrierSetC1::ensure_in_register(LIRGenerator* gen, LIR_Opr obj) {
159 if (!obj->is_register()) {
160 LIR_Opr obj_reg;
161 if (obj->is_constant()) {
162 obj_reg = gen->new_register(T_OBJECT);
163 __ move(obj, obj_reg);
164 } else {
165 #ifdef AARCH64
166 // AArch64 expects double-size register.
167 obj_reg = gen->new_pointer_register();
168 #else
169 // x86 expects single-size register.
170 obj_reg = gen->new_register(T_OBJECT);
171 #endif
172 __ leal(obj, obj_reg);
173 }
174 obj = obj_reg;
175 }
176 return obj;
177 }
178
179 LIR_Opr ShenandoahBarrierSetC1::storeval_barrier(LIRGenerator* gen, LIR_Opr obj, CodeEmitInfo* info, DecoratorSet decorators) {
180 if (ShenandoahStoreValEnqueueBarrier) {
181 obj = ensure_in_register(gen, obj);
182 pre_barrier(gen, info, decorators, LIR_OprFact::illegalOpr, obj);
183 }
184 return obj;
185 }
186
187 void ShenandoahBarrierSetC1::store_at_resolved(LIRAccess& access, LIR_Opr value) {
188 if (access.is_oop()) {
189 if (ShenandoahSATBBarrier) {
190 pre_barrier(access.gen(), access.access_emit_info(), access.decorators(), access.resolved_addr(), LIR_OprFact::illegalOpr /* pre_val */);
191 }
192 value = storeval_barrier(access.gen(), value, access.access_emit_info(), access.decorators());
193 }
194 BarrierSetC1::store_at_resolved(access, value);
195 }
196
197 LIR_Opr ShenandoahBarrierSetC1::resolve_address(LIRAccess& access, bool resolve_in_register) {
198 // We must resolve in register when patching. This is to avoid
199 // having a patch area in the load barrier stub, since the call
200 // into the runtime to patch will not have the proper oop map.
201 const bool patch_before_barrier = access.is_oop() && (access.decorators() & C1_NEEDS_PATCHING) != 0;
202 return BarrierSetC1::resolve_address(access, resolve_in_register || patch_before_barrier);
203 }
204
205 void ShenandoahBarrierSetC1::load_at_resolved(LIRAccess& access, LIR_Opr result) {
206 if (!access.is_oop()) {
207 BarrierSetC1::load_at_resolved(access, result);
208 return;
209 }
210
211 LIRGenerator* gen = access.gen();
212
213 DecoratorSet decorators = access.decorators();
214 bool is_traversal_mode = ShenandoahHeap::heap()->is_traversal_mode();
215
216 if ((decorators & IN_NATIVE) != 0 && !is_traversal_mode) {
217 assert(access.is_oop(), "IN_NATIVE access only for oop values");
218 BarrierSetC1::load_at_resolved(access, result);
219 LIR_OprList* args = new LIR_OprList();
220 LIR_Opr addr = access.resolved_addr();
221 addr = ensure_in_register(gen, addr);
222 args->append(result);
223 args->append(addr);
224 BasicTypeList signature;
225 signature.append(T_OBJECT);
226 signature.append(T_ADDRESS);
227 LIR_Opr call_result = gen->call_runtime(&signature, args,
228 CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_native),
229 objectType, NULL);
230 __ move(call_result, result);
231 } else {
232 if (ShenandoahLoadRefBarrier) {
233 LIR_Opr tmp = gen->new_register(T_OBJECT);
234 BarrierSetC1::load_at_resolved(access, tmp);
235 tmp = load_reference_barrier(access.gen(), tmp, access.resolved_addr());
236 __ move(tmp, result);
237 } else {
238 BarrierSetC1::load_at_resolved(access, result);
239 }
240 }
241
242 if (ShenandoahKeepAliveBarrier) {
243 bool is_weak = (decorators & ON_WEAK_OOP_REF) != 0;
244 bool is_phantom = (decorators & ON_PHANTOM_OOP_REF) != 0;
245 bool is_anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0;
246 bool keep_alive = (decorators & AS_NO_KEEPALIVE) == 0 || is_traversal_mode;
247
248 if ((is_weak || is_phantom || is_anonymous) && keep_alive) {
249 // Register the value in the referent field with the pre-barrier
250 LabelObj *Lcont_anonymous;
251 if (is_anonymous) {
252 Lcont_anonymous = new LabelObj();
253 generate_referent_check(access, Lcont_anonymous);
254 }
255 pre_barrier(access.gen(), access.access_emit_info(), access.decorators(), LIR_OprFact::illegalOpr /* addr_opr */,
256 result /* pre_val */);
257 if (is_anonymous) {
258 __ branch_destination(Lcont_anonymous->label());
259 }
260 }
261 }
262 }
263
264 class C1ShenandoahPreBarrierCodeGenClosure : public StubAssemblerCodeGenClosure {
265 virtual OopMapSet* generate_code(StubAssembler* sasm) {
266 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
267 bs->generate_c1_pre_barrier_runtime_stub(sasm);
268 return NULL;
269 }
270 };
271
272 class C1ShenandoahLoadReferenceBarrierCodeGenClosure : public StubAssemblerCodeGenClosure {
273 virtual OopMapSet* generate_code(StubAssembler* sasm) {
274 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
275 bs->generate_c1_load_reference_barrier_runtime_stub(sasm);
276 return NULL;
277 }
278 };
279
280 void ShenandoahBarrierSetC1::generate_c1_runtime_stubs(BufferBlob* buffer_blob) {
281 C1ShenandoahPreBarrierCodeGenClosure pre_code_gen_cl;
282 _pre_barrier_c1_runtime_code_blob = Runtime1::generate_blob(buffer_blob, -1,
283 "shenandoah_pre_barrier_slow",
284 false, &pre_code_gen_cl);
285 if (ShenandoahLoadRefBarrier) {
286 C1ShenandoahLoadReferenceBarrierCodeGenClosure lrb_code_gen_cl;
287 _load_reference_barrier_rt_code_blob = Runtime1::generate_blob(buffer_blob, -1,
288 "shenandoah_load_reference_barrier_slow",
289 false, &lrb_code_gen_cl);
290 }
291 }
292
293 const char* ShenandoahBarrierSetC1::rtcall_name_for_address(address entry) {
294 if (entry == CAST_FROM_FN_PTR(address, ShenandoahRuntime::load_reference_barrier_native)) {
295 return "ShenandoahRuntime::load_reference_barrier_native";
296 }
297 return NULL;
298 }