1 /*
2 * Copyright (c) 2018, 2020, Red Hat, Inc. 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 "c1/c1_IR.hpp"
27 #include "gc/shared/satbMarkQueue.hpp"
28 #include "gc/shenandoah/shenandoahBarrierSet.hpp"
29 #include "gc/shenandoah/shenandoahBarrierSetAssembler.hpp"
30 #include "gc/shenandoah/shenandoahHeap.hpp"
31 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
32 #include "gc/shenandoah/shenandoahRuntime.hpp"
33 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
34 #include "gc/shenandoah/c1/shenandoahBarrierSetC1.hpp"
35
36 #ifdef ASSERT
37 #define __ gen->lir(__FILE__, __LINE__)->
38 #else
39 #define __ gen->lir()->
40 #endif
41
42 void ShenandoahPreBarrierStub::emit_code(LIR_Assembler* ce) {
43 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
44 bs->gen_pre_barrier_stub(ce, this);
45 }
46
47 void ShenandoahLoadReferenceBarrierStub::emit_code(LIR_Assembler* ce) {
48 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
49 bs->gen_load_reference_barrier_stub(ce, this);
50 }
51
52 ShenandoahBarrierSetC1::ShenandoahBarrierSetC1() :
53 _pre_barrier_c1_runtime_code_blob(NULL),
54 _load_reference_barrier_rt_code_blob(NULL) {}
55
56 void ShenandoahBarrierSetC1::pre_barrier(LIRGenerator* gen, CodeEmitInfo* info, DecoratorSet decorators, LIR_Opr addr_opr, LIR_Opr pre_val) {
57 // First we test whether marking is in progress.
58 BasicType flag_type;
59 bool patch = (decorators & C1_NEEDS_PATCHING) != 0;
60 bool do_load = pre_val == LIR_OprFact::illegalOpr;
61 if (in_bytes(SATBMarkQueue::byte_width_of_active()) == 4) {
62 flag_type = T_INT;
63 } else {
64 guarantee(in_bytes(SATBMarkQueue::byte_width_of_active()) == 1,
65 "Assumption");
66 // Use unsigned type T_BOOLEAN here rather than signed T_BYTE since some platforms, eg. ARM,
67 // need to use unsigned instructions to use the large offset to load the satb_mark_queue.
68 flag_type = T_BOOLEAN;
69 }
70 LIR_Opr thrd = gen->getThreadPointer();
71 LIR_Address* mark_active_flag_addr =
72 new LIR_Address(thrd,
73 in_bytes(ShenandoahThreadLocalData::satb_mark_queue_active_offset()),
74 flag_type);
75 // Read the marking-in-progress flag.
76 LIR_Opr flag_val = gen->new_register(T_INT);
77 __ load(mark_active_flag_addr, flag_val);
78 __ cmp(lir_cond_notEqual, flag_val, LIR_OprFact::intConst(0));
79
80 LIR_PatchCode pre_val_patch_code = lir_patch_none;
81
82 CodeStub* slow;
83
84 if (do_load) {
85 assert(pre_val == LIR_OprFact::illegalOpr, "sanity");
86 assert(addr_opr != LIR_OprFact::illegalOpr, "sanity");
87
88 if (patch)
89 pre_val_patch_code = lir_patch_normal;
90
91 pre_val = gen->new_register(T_OBJECT);
92
93 if (!addr_opr->is_address()) {
94 assert(addr_opr->is_register(), "must be");
95 addr_opr = LIR_OprFact::address(new LIR_Address(addr_opr, T_OBJECT));
96 }
97 slow = new ShenandoahPreBarrierStub(addr_opr, pre_val, pre_val_patch_code, info ? new CodeEmitInfo(info) : NULL);
98 } else {
99 assert(addr_opr == LIR_OprFact::illegalOpr, "sanity");
100 assert(pre_val->is_register(), "must be");
101 assert(pre_val->type() == T_OBJECT, "must be an object");
102
103 slow = new ShenandoahPreBarrierStub(pre_val);
104 }
105
106 __ branch(lir_cond_notEqual, T_INT, slow);
107 __ branch_destination(slow->continuation());
108 }
109
110 LIR_Opr ShenandoahBarrierSetC1::load_reference_barrier(LIRGenerator* gen, LIR_Opr obj, LIR_Opr addr, bool is_native) {
111 if (ShenandoahLoadRefBarrier) {
112 return load_reference_barrier_impl(gen, obj, addr, is_native);
113 } else {
114 return obj;
115 }
116 }
117
118 LIR_Opr ShenandoahBarrierSetC1::load_reference_barrier_impl(LIRGenerator* gen, LIR_Opr obj, LIR_Opr addr, bool is_native) {
119 assert(ShenandoahLoadRefBarrier, "Should be enabled");
120
121 obj = ensure_in_register(gen, obj, T_OBJECT);
122 assert(obj->is_register(), "must be a register at this point");
123 addr = ensure_in_register(gen, addr, T_ADDRESS);
124 assert(addr->is_register(), "must be a register at this point");
125 LIR_Opr result = gen->result_register_for(obj->value_type());
126 __ move(obj, result);
127 LIR_Opr tmp1 = gen->new_register(T_ADDRESS);
128 LIR_Opr tmp2 = gen->new_register(T_ADDRESS);
129
130 LIR_Opr thrd = gen->getThreadPointer();
131 LIR_Address* active_flag_addr =
132 new LIR_Address(thrd,
133 in_bytes(ShenandoahThreadLocalData::gc_state_offset()),
134 T_BYTE);
135 // Read and check the gc-state-flag.
136 LIR_Opr flag_val = gen->new_register(T_INT);
137 __ load(active_flag_addr, flag_val);
138 LIR_Opr mask = LIR_OprFact::intConst(ShenandoahHeap::HAS_FORWARDED |
139 ShenandoahHeap::EVACUATION |
140 ShenandoahHeap::TRAVERSAL);
141 LIR_Opr mask_reg = gen->new_register(T_INT);
142 __ move(mask, mask_reg);
143
144 if (TwoOperandLIRForm) {
145 __ logical_and(flag_val, mask_reg, flag_val);
146 } else {
147 LIR_Opr masked_flag = gen->new_register(T_INT);
148 __ logical_and(flag_val, mask_reg, masked_flag);
149 flag_val = masked_flag;
150 }
151 __ cmp(lir_cond_notEqual, flag_val, LIR_OprFact::intConst(0));
152
153 CodeStub* slow = new ShenandoahLoadReferenceBarrierStub(obj, addr, result, tmp1, tmp2, is_native);
154 __ branch(lir_cond_notEqual, T_INT, slow);
155 __ branch_destination(slow->continuation());
156
157 return result;
158 }
159
160 LIR_Opr ShenandoahBarrierSetC1::ensure_in_register(LIRGenerator* gen, LIR_Opr obj, BasicType type) {
161 if (!obj->is_register()) {
162 LIR_Opr obj_reg;
163 if (obj->is_constant()) {
164 obj_reg = gen->new_register(type);
165 __ move(obj, obj_reg);
166 } else {
167 obj_reg = gen->new_pointer_register();
168 __ leal(obj, obj_reg);
169 }
170 obj = obj_reg;
171 }
172 return obj;
173 }
174
175 LIR_Opr ShenandoahBarrierSetC1::storeval_barrier(LIRGenerator* gen, LIR_Opr obj, CodeEmitInfo* info, DecoratorSet decorators) {
176 if (ShenandoahStoreValEnqueueBarrier) {
177 obj = ensure_in_register(gen, obj, T_OBJECT);
178 pre_barrier(gen, info, decorators, LIR_OprFact::illegalOpr, obj);
179 }
180 return obj;
181 }
182
183 void ShenandoahBarrierSetC1::store_at_resolved(LIRAccess& access, LIR_Opr value) {
184 if (access.is_oop()) {
185 if (ShenandoahSATBBarrier) {
186 pre_barrier(access.gen(), access.access_emit_info(), access.decorators(), access.resolved_addr(), LIR_OprFact::illegalOpr /* pre_val */);
187 }
188 value = storeval_barrier(access.gen(), value, access.access_emit_info(), access.decorators());
189 }
190 BarrierSetC1::store_at_resolved(access, value);
191 }
192
193 LIR_Opr ShenandoahBarrierSetC1::resolve_address(LIRAccess& access, bool resolve_in_register) {
194 // We must resolve in register when patching. This is to avoid
195 // having a patch area in the load barrier stub, since the call
196 // into the runtime to patch will not have the proper oop map.
197 const bool patch_before_barrier = access.is_oop() && (access.decorators() & C1_NEEDS_PATCHING) != 0;
198 return BarrierSetC1::resolve_address(access, resolve_in_register || patch_before_barrier);
199 }
200
201 void ShenandoahBarrierSetC1::load_at_resolved(LIRAccess& access, LIR_Opr result) {
202 // 1: non-reference load, no additional barrier is needed
203 if (!access.is_oop()) {
204 BarrierSetC1::load_at_resolved(access, result);
205 return;
206 }
207
208 LIRGenerator* gen = access.gen();
209 DecoratorSet decorators = access.decorators();
210 BasicType type = access.type();
211
212 // 2: load a reference from src location and apply LRB if ShenandoahLoadRefBarrier is set
213 if (ShenandoahBarrierSet::need_load_reference_barrier(decorators, type)) {
214 LIR_Opr tmp = gen->new_register(T_OBJECT);
215 BarrierSetC1::load_at_resolved(access, tmp);
216 bool is_native = ShenandoahBarrierSet::use_load_reference_barrier_native(decorators, type);
217 tmp = load_reference_barrier(gen, tmp, access.resolved_addr(), is_native);
218 __ move(tmp, result);
219 } else {
220 BarrierSetC1::load_at_resolved(access, result);
221 }
222
223 // 3: apply keep-alive barrier if ShenandoahSATBBarrier is set
224 if (ShenandoahSATBBarrier) {
225 bool is_weak = (decorators & ON_WEAK_OOP_REF) != 0;
226 bool is_phantom = (decorators & ON_PHANTOM_OOP_REF) != 0;
227 bool is_anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0;
228 bool is_traversal_mode = ShenandoahHeap::heap()->is_traversal_mode();
229 bool keep_alive = (decorators & AS_NO_KEEPALIVE) == 0 || is_traversal_mode;
230
231 if ((is_weak || is_phantom || is_anonymous) && keep_alive) {
232 // Register the value in the referent field with the pre-barrier
233 LabelObj *Lcont_anonymous;
234 if (is_anonymous) {
235 Lcont_anonymous = new LabelObj();
236 generate_referent_check(access, Lcont_anonymous);
237 }
238 pre_barrier(gen, access.access_emit_info(), decorators, LIR_OprFact::illegalOpr /* addr_opr */,
239 result /* pre_val */);
240 if (is_anonymous) {
241 __ branch_destination(Lcont_anonymous->label());
242 }
243 }
244 }
245 }
246
247 class C1ShenandoahPreBarrierCodeGenClosure : public StubAssemblerCodeGenClosure {
248 virtual OopMapSet* generate_code(StubAssembler* sasm) {
249 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
250 bs->generate_c1_pre_barrier_runtime_stub(sasm);
251 return NULL;
252 }
253 };
254
255 class C1ShenandoahLoadReferenceBarrierCodeGenClosure : public StubAssemblerCodeGenClosure {
256 private:
257 const bool _is_native;
258
259 public:
260 C1ShenandoahLoadReferenceBarrierCodeGenClosure(bool is_native) : _is_native(is_native) {}
261
262 virtual OopMapSet* generate_code(StubAssembler* sasm) {
263 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
264 bs->generate_c1_load_reference_barrier_runtime_stub(sasm, _is_native);
265 return NULL;
266 }
267 };
268
269 void ShenandoahBarrierSetC1::generate_c1_runtime_stubs(BufferBlob* buffer_blob) {
270 C1ShenandoahPreBarrierCodeGenClosure pre_code_gen_cl;
271 _pre_barrier_c1_runtime_code_blob = Runtime1::generate_blob(buffer_blob, -1,
272 "shenandoah_pre_barrier_slow",
273 false, &pre_code_gen_cl);
274 if (ShenandoahLoadRefBarrier) {
275 C1ShenandoahLoadReferenceBarrierCodeGenClosure lrb_code_gen_cl(false);
276 _load_reference_barrier_rt_code_blob = Runtime1::generate_blob(buffer_blob, -1,
277 "shenandoah_load_reference_barrier_slow",
278 false, &lrb_code_gen_cl);
279
280 C1ShenandoahLoadReferenceBarrierCodeGenClosure lrb_native_code_gen_cl(true);
281 _load_reference_barrier_native_rt_code_blob = Runtime1::generate_blob(buffer_blob, -1,
282 "shenandoah_load_reference_barrier_native_slow",
283 false, &lrb_native_code_gen_cl);
284 }
285 }