1 /*
2 * Copyright (c) 2015, 2018, 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 #include "precompiled.hpp"
25 #include "c1/c1_LIR.hpp"
26 #include "c1/c1_LIRGenerator.hpp"
27 #include "c1/c1_CodeStubs.hpp"
28 #include "gc/z/c1/zBarrierSetC1.hpp"
29 #include "gc/z/zBarrierSet.hpp"
30 #include "gc/z/zBarrierSetAssembler.hpp"
31 #include "gc/z/zThreadLocalData.hpp"
32 #include "utilities/macros.hpp"
33
34 ZLoadBarrierStubC1::ZLoadBarrierStubC1(LIRAccess& access, LIR_Opr ref, address runtime_stub) :
35 _decorators(access.decorators()),
36 _ref_addr(access.resolved_addr()),
37 _ref(ref),
38 _tmp(LIR_OprFact::illegalOpr),
39 _runtime_stub(runtime_stub) {
40
41 // Allocate tmp register if needed
42 if (!_ref_addr->is_register()) {
43 assert(_ref_addr->is_address(), "Must be an address");
44 if (_ref_addr->as_address_ptr()->index()->is_valid() ||
45 _ref_addr->as_address_ptr()->disp() != 0) {
46 // Has index or displacement, need tmp register to load address into
47 _tmp = access.gen()->new_pointer_register();
48 } else {
49 // No index or displacement, address available in base register
50 _ref_addr = _ref_addr->as_address_ptr()->base();
51 }
52 }
53
54 assert(_ref->is_register(), "Must be a register");
55 assert(_ref_addr->is_register() != _tmp->is_register(), "Only one should be a register");
56 }
57
58 DecoratorSet ZLoadBarrierStubC1::decorators() const {
59 return _decorators;
60 }
61
62 LIR_Opr ZLoadBarrierStubC1::ref() const {
63 return _ref;
64 }
65
66 LIR_Opr ZLoadBarrierStubC1::ref_addr() const {
67 return _ref_addr;
68 }
69
70 LIR_Opr ZLoadBarrierStubC1::tmp() const {
71 return _tmp;
72 }
73
74 address ZLoadBarrierStubC1::runtime_stub() const {
75 return _runtime_stub;
76 }
77
78 void ZLoadBarrierStubC1::visit(LIR_OpVisitState* visitor) {
79 visitor->do_slow_case();
80 visitor->do_input(_ref_addr);
81 visitor->do_output(_ref);
82 if (_tmp->is_valid()) {
83 visitor->do_temp(_tmp);
84 }
85 }
86
87 void ZLoadBarrierStubC1::emit_code(LIR_Assembler* ce) {
88 ZBarrierSet::assembler()->generate_c1_load_barrier_stub(ce, this);
89 }
90
91 #ifndef PRODUCT
92 void ZLoadBarrierStubC1::print_name(outputStream* out) const {
93 out->print("ZLoadBarrierStubC1");
94 }
95 #endif // PRODUCT
96
97 class LIR_OpZLoadBarrierTest : public LIR_Op {
98 private:
99 LIR_Opr _opr;
100
101 public:
102 LIR_OpZLoadBarrierTest(LIR_Opr opr) :
103 LIR_Op(),
104 _opr(opr) {}
105
106 virtual void visit(LIR_OpVisitState* state) {
107 state->do_input(_opr);
108 }
109
110 virtual void emit_code(LIR_Assembler* ce) {
111 ZBarrierSet::assembler()->generate_c1_load_barrier_test(ce, _opr);
112 }
113
114 virtual void print_instr(outputStream* out) const {
115 _opr->print(out);
116 out->print(" ");
117 }
118
119 #ifndef PRODUCT
120 virtual const char* name() const {
121 return "lir_z_load_barrier_test";
122 }
123 #endif // PRODUCT
124 };
125
126 static bool barrier_needed(LIRAccess& access) {
127 return ZBarrierSet::barrier_needed(access.decorators(), access.type());
128 }
129
130 ZBarrierSetC1::ZBarrierSetC1() :
131 _load_barrier_on_oop_field_preloaded_runtime_stub(NULL),
132 _load_barrier_on_weak_oop_field_preloaded_runtime_stub(NULL) {}
133
134 address ZBarrierSetC1::load_barrier_on_oop_field_preloaded_runtime_stub(DecoratorSet decorators) const {
135 assert((decorators & ON_PHANTOM_OOP_REF) == 0, "Unsupported decorator");
136 //assert((decorators & ON_UNKNOWN_OOP_REF) == 0, "Unsupported decorator");
137
138 if ((decorators & ON_WEAK_OOP_REF) != 0) {
139 return _load_barrier_on_weak_oop_field_preloaded_runtime_stub;
140 } else {
141 return _load_barrier_on_oop_field_preloaded_runtime_stub;
142 }
143 }
144
145 #ifdef ASSERT
146 #define __ access.gen()->lir(__FILE__, __LINE__)->
147 #else
148 #define __ access.gen()->lir()->
149 #endif
150
151 void ZBarrierSetC1::load_barrier(LIRAccess& access, LIR_Opr result) const {
152 // Fast path
153 __ append(new LIR_OpZLoadBarrierTest(result));
154
155 // Slow path
156 const address runtime_stub = load_barrier_on_oop_field_preloaded_runtime_stub(access.decorators());
157 CodeStub* const stub = new ZLoadBarrierStubC1(access, result, runtime_stub);
158 __ branch(lir_cond_notEqual, T_ADDRESS, stub);
159 __ branch_destination(stub->continuation());
160 }
161
162 LIR_Opr ZBarrierSetC1::resolve_address(LIRAccess& access, bool resolve_in_register) {
163 // We must resolve in register when patching. This is to avoid
164 // having a patch area in the load barrier stub, since the call
165 // into the runtime to patch will not have the proper oop map.
166 const bool patch_before_barrier = barrier_needed(access) && (access.decorators() & C1_NEEDS_PATCHING) != 0;
167 return BarrierSetC1::resolve_address(access, resolve_in_register || patch_before_barrier);
168 }
169
170 #undef __
171
172 void ZBarrierSetC1::load_at_resolved(LIRAccess& access, LIR_Opr result) {
173 BarrierSetC1::load_at_resolved(access, result);
174
175 if (barrier_needed(access)) {
176 load_barrier(access, result);
177 }
178 }
179
180 static void pre_load_barrier(LIRAccess& access) {
181 DecoratorSet decorators = access.decorators();
182
183 // Downgrade access to MO_UNORDERED
184 decorators = (decorators & ~MO_DECORATOR_MASK) | MO_UNORDERED;
185
186 // Remove ACCESS_WRITE
187 decorators = (decorators & ~ACCESS_WRITE);
188
189 // Generate synthetic load at
190 access.gen()->access_load_at(decorators,
191 access.type(),
192 access.base().item(),
193 access.offset().opr(),
194 access.gen()->new_register(access.type()),
195 NULL /* patch_emit_info */,
196 NULL /* load_emit_info */);
197 }
198
199 LIR_Opr ZBarrierSetC1::atomic_xchg_at_resolved(LIRAccess& access, LIRItem& value) {
200 if (barrier_needed(access)) {
201 pre_load_barrier(access);
202 }
203
204 return BarrierSetC1::atomic_xchg_at_resolved(access, value);
205 }
206
207 LIR_Opr ZBarrierSetC1::atomic_cmpxchg_at_resolved(LIRAccess& access, LIRItem& cmp_value, LIRItem& new_value) {
208 if (barrier_needed(access)) {
209 pre_load_barrier(access);
210 }
211
212 return BarrierSetC1::atomic_cmpxchg_at_resolved(access, cmp_value, new_value);
213 }
214
215 class ZLoadBarrierRuntimeStubCodeGenClosure : public StubAssemblerCodeGenClosure {
216 private:
217 const DecoratorSet _decorators;
218
219 public:
220 ZLoadBarrierRuntimeStubCodeGenClosure(DecoratorSet decorators) :
221 _decorators(decorators) {}
222
223 virtual OopMapSet* generate_code(StubAssembler* sasm) {
224 ZBarrierSet::assembler()->generate_c1_load_barrier_runtime_stub(sasm, _decorators);
225 return NULL;
226 }
227 };
228
229 static address generate_c1_runtime_stub(BufferBlob* blob, DecoratorSet decorators, const char* name) {
230 ZLoadBarrierRuntimeStubCodeGenClosure cl(decorators);
231 CodeBlob* const code_blob = Runtime1::generate_blob(blob, -1 /* stub_id */, name, false /* expect_oop_map*/, &cl);
232 return code_blob->code_begin();
233 }
234
235 void ZBarrierSetC1::generate_c1_runtime_stubs(BufferBlob* blob) {
236 _load_barrier_on_oop_field_preloaded_runtime_stub =
237 generate_c1_runtime_stub(blob, ON_STRONG_OOP_REF, "load_barrier_on_oop_field_preloaded_runtime_stub");
238 _load_barrier_on_weak_oop_field_preloaded_runtime_stub =
239 generate_c1_runtime_stub(blob, ON_WEAK_OOP_REF, "load_barrier_on_weak_oop_field_preloaded_runtime_stub");
240 }