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/shenandoah/shenandoahBarrierSetAssembler.hpp"
27 #include "gc/shenandoah/shenandoahHeap.hpp"
28 #include "gc/shenandoah/shenandoahHeapRegion.hpp"
29 #include "gc/shenandoah/shenandoahSATBMarkQueue.hpp"
30 #include "gc/shenandoah/shenandoahThreadLocalData.hpp"
31 #include "gc/shenandoah/c1/shenandoahBarrierSetC1.hpp"
32
33 #ifdef ASSERT
34 #define __ gen->lir(__FILE__, __LINE__)->
35 #else
36 #define __ gen->lir()->
37 #endif
38
39 void ShenandoahPreBarrierStub::emit_code(LIR_Assembler* ce) {
40 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
41 bs->gen_pre_barrier_stub(ce, this);
42 }
43
44 void ShenandoahLoadReferenceBarrierStub::emit_code(LIR_Assembler* ce) {
45 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
46 bs->gen_load_reference_barrier_stub(ce, this);
47 }
48
49 ShenandoahBarrierSetC1::ShenandoahBarrierSetC1() :
50 _pre_barrier_c1_runtime_code_blob(NULL),
51 _load_reference_barrier_rt_code_blob(NULL) {}
52
53 void ShenandoahBarrierSetC1::pre_barrier(LIRGenerator* gen, CodeEmitInfo* info, DecoratorSet decorators, LIR_Opr addr_opr, LIR_Opr pre_val) {
54 // First we test whether marking is in progress.
55 BasicType flag_type;
56 bool patch = (decorators & C1_NEEDS_PATCHING) != 0;
57 bool do_load = pre_val == LIR_OprFact::illegalOpr;
58 if (in_bytes(ShenandoahSATBMarkQueue::byte_width_of_active()) == 4) {
59 flag_type = T_INT;
60 } else {
61 guarantee(in_bytes(ShenandoahSATBMarkQueue::byte_width_of_active()) == 1,
62 "Assumption");
63 // Use unsigned type T_BOOLEAN here rather than signed T_BYTE since some platforms, eg. ARM,
64 // need to use unsigned instructions to use the large offset to load the satb_mark_queue.
65 flag_type = T_BOOLEAN;
66 }
67 LIR_Opr thrd = gen->getThreadPointer();
68 LIR_Address* mark_active_flag_addr =
69 new LIR_Address(thrd,
70 in_bytes(ShenandoahThreadLocalData::satb_mark_queue_active_offset()),
71 flag_type);
72 // Read the marking-in-progress flag.
73 LIR_Opr flag_val = gen->new_register(T_INT);
74 __ load(mark_active_flag_addr, flag_val);
75 __ cmp(lir_cond_notEqual, flag_val, LIR_OprFact::intConst(0));
76
77 LIR_PatchCode pre_val_patch_code = lir_patch_none;
78
79 CodeStub* slow;
80
81 if (do_load) {
82 assert(pre_val == LIR_OprFact::illegalOpr, "sanity");
83 assert(addr_opr != LIR_OprFact::illegalOpr, "sanity");
84
85 if (patch)
86 pre_val_patch_code = lir_patch_normal;
87
88 pre_val = gen->new_register(T_OBJECT);
89
90 if (!addr_opr->is_address()) {
91 assert(addr_opr->is_register(), "must be");
92 addr_opr = LIR_OprFact::address(new LIR_Address(addr_opr, T_OBJECT));
93 }
94 slow = new ShenandoahPreBarrierStub(addr_opr, pre_val, pre_val_patch_code, info ? new CodeEmitInfo(info) : NULL);
95 } else {
96 assert(addr_opr == LIR_OprFact::illegalOpr, "sanity");
97 assert(pre_val->is_register(), "must be");
98 assert(pre_val->type() == T_OBJECT, "must be an object");
99
100 slow = new ShenandoahPreBarrierStub(pre_val);
101 }
102
103 __ branch(lir_cond_notEqual, T_INT, slow);
104 __ branch_destination(slow->continuation());
105 }
106
107 LIR_Opr ShenandoahBarrierSetC1::load_reference_barrier(LIRGenerator* gen, LIR_Opr obj, LIR_Opr addr) {
108 if (ShenandoahLoadRefBarrier) {
109 return load_reference_barrier_impl(gen, obj, addr);
110 } else {
111 return obj;
112 }
113 }
114
115 LIR_Opr ShenandoahBarrierSetC1::load_reference_barrier_impl(LIRGenerator* gen, LIR_Opr obj, LIR_Opr addr) {
116 assert(ShenandoahLoadRefBarrier, "Should be enabled");
117
118 obj = ensure_in_register(gen, obj);
119 assert(obj->is_register(), "must be a register at this point");
120 addr = ensure_in_register(gen, addr);
121 assert(addr->is_register(), "must be a register at this point");
122 LIR_Opr result = gen->result_register_for(obj->value_type());
123 __ move(obj, result);
124 LIR_Opr tmp1 = gen->new_register(T_OBJECT);
125 LIR_Opr tmp2 = gen->new_register(T_OBJECT);
126
127 LIR_Opr thrd = gen->getThreadPointer();
128 LIR_Address* active_flag_addr =
129 new LIR_Address(thrd,
130 in_bytes(ShenandoahThreadLocalData::gc_state_offset()),
131 T_BYTE);
132 // Read and check the gc-state-flag.
133 LIR_Opr flag_val = gen->new_register(T_INT);
134 __ load(active_flag_addr, flag_val);
135 LIR_Opr mask = LIR_OprFact::intConst(ShenandoahHeap::HAS_FORWARDED |
136 ShenandoahHeap::EVACUATION |
137 ShenandoahHeap::TRAVERSAL);
138 LIR_Opr mask_reg = gen->new_register(T_INT);
139 __ move(mask, mask_reg);
140
141 if (TwoOperandLIRForm) {
142 __ logical_and(flag_val, mask_reg, flag_val);
143 } else {
144 LIR_Opr masked_flag = gen->new_register(T_INT);
145 __ logical_and(flag_val, mask_reg, masked_flag);
146 flag_val = masked_flag;
147 }
148 __ cmp(lir_cond_notEqual, flag_val, LIR_OprFact::intConst(0));
149
150 CodeStub* slow = new ShenandoahLoadReferenceBarrierStub(obj, addr, result, tmp1, tmp2);
151 __ branch(lir_cond_notEqual, T_INT, slow);
152 __ branch_destination(slow->continuation());
153
154 return result;
155 }
156
157 LIR_Opr ShenandoahBarrierSetC1::ensure_in_register(LIRGenerator* gen, LIR_Opr obj) {
158 if (!obj->is_register()) {
159 LIR_Opr obj_reg;
160 if (obj->is_constant()) {
161 obj_reg = gen->new_register(T_OBJECT);
162 __ move(obj, obj_reg);
163 } else {
164 #ifdef AARCH64
165 // AArch64 expects double-size register.
166 obj_reg = gen->new_pointer_register();
167 #else
168 // x86 expects single-size register.
169 obj_reg = gen->new_register(T_OBJECT);
170 #endif
171 __ leal(obj, obj_reg);
172 }
173 obj = obj_reg;
174 }
175 return obj;
176 }
177
178 LIR_Opr ShenandoahBarrierSetC1::storeval_barrier(LIRGenerator* gen, LIR_Opr obj, CodeEmitInfo* info, DecoratorSet decorators) {
179 if (ShenandoahStoreValEnqueueBarrier) {
180 obj = ensure_in_register(gen, obj);
181 pre_barrier(gen, info, decorators, LIR_OprFact::illegalOpr, obj);
182 }
183 return obj;
184 }
185
186 void ShenandoahBarrierSetC1::store_at_resolved(LIRAccess& access, LIR_Opr value) {
187 if (access.is_oop()) {
188 if (ShenandoahSATBBarrier) {
189 pre_barrier(access.gen(), access.access_emit_info(), access.decorators(), access.resolved_addr(), LIR_OprFact::illegalOpr /* pre_val */);
190 }
191 value = storeval_barrier(access.gen(), value, access.access_emit_info(), access.decorators());
192 }
193 BarrierSetC1::store_at_resolved(access, value);
194 }
195
196 LIR_Opr ShenandoahBarrierSetC1::resolve_address(LIRAccess& access, bool resolve_in_register) {
197 // We must resolve in register when patching. This is to avoid
198 // having a patch area in the load barrier stub, since the call
199 // into the runtime to patch will not have the proper oop map.
200 const bool patch_before_barrier = access.is_oop() && (access.decorators() & C1_NEEDS_PATCHING) != 0;
201 return BarrierSetC1::resolve_address(access, resolve_in_register || patch_before_barrier);
202 }
203
204 void ShenandoahBarrierSetC1::load_at_resolved(LIRAccess& access, LIR_Opr result) {
205 if (!access.is_oop()) {
206 BarrierSetC1::load_at_resolved(access, result);
207 return;
208 }
209
210 LIRGenerator *gen = access.gen();
211
212 if (ShenandoahLoadRefBarrier) {
213 LIR_Opr tmp = gen->new_register(T_OBJECT);
214 BarrierSetC1::load_at_resolved(access, tmp);
215 tmp = load_reference_barrier(access.gen(), tmp, access.resolved_addr());
216 __ move(tmp, result);
217 } else {
218 BarrierSetC1::load_at_resolved(access, result);
219 }
220
221 if (ShenandoahKeepAliveBarrier) {
222 DecoratorSet decorators = access.decorators();
223 bool is_weak = (decorators & ON_WEAK_OOP_REF) != 0;
224 bool is_phantom = (decorators & ON_PHANTOM_OOP_REF) != 0;
225 bool is_anonymous = (decorators & ON_UNKNOWN_OOP_REF) != 0;
226 if (is_weak || is_phantom || is_anonymous) {
227 // Register the value in the referent field with the pre-barrier
228 LabelObj *Lcont_anonymous;
229 if (is_anonymous) {
230 Lcont_anonymous = new LabelObj();
231 generate_referent_check(access, Lcont_anonymous);
232 }
233 pre_barrier(access.gen(), access.access_emit_info(), access.decorators(), LIR_OprFact::illegalOpr /* addr_opr */,
234 result /* pre_val */);
235 if (is_anonymous) {
236 __ branch_destination(Lcont_anonymous->label());
237 }
238 }
239 }
240 }
241
242 class C1ShenandoahPreBarrierCodeGenClosure : public StubAssemblerCodeGenClosure {
243 virtual OopMapSet* generate_code(StubAssembler* sasm) {
244 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
245 bs->generate_c1_pre_barrier_runtime_stub(sasm);
246 return NULL;
247 }
248 };
249
250 class C1ShenandoahLoadReferenceBarrierCodeGenClosure : public StubAssemblerCodeGenClosure {
251 virtual OopMapSet* generate_code(StubAssembler* sasm) {
252 ShenandoahBarrierSetAssembler* bs = (ShenandoahBarrierSetAssembler*)BarrierSet::barrier_set()->barrier_set_assembler();
253 bs->generate_c1_load_reference_barrier_runtime_stub(sasm);
254 return NULL;
255 }
256 };
257
258 void ShenandoahBarrierSetC1::generate_c1_runtime_stubs(BufferBlob* buffer_blob) {
259 C1ShenandoahPreBarrierCodeGenClosure pre_code_gen_cl;
260 _pre_barrier_c1_runtime_code_blob = Runtime1::generate_blob(buffer_blob, -1,
261 "shenandoah_pre_barrier_slow",
262 false, &pre_code_gen_cl);
263 if (ShenandoahLoadRefBarrier) {
264 C1ShenandoahLoadReferenceBarrierCodeGenClosure lrb_code_gen_cl;
265 _load_reference_barrier_rt_code_blob = Runtime1::generate_blob(buffer_blob, -1,
266 "shenandoah_load_reference_barrier_slow",
267 false, &lrb_code_gen_cl);
268 }
269 }