1 // Copyright 2013 the V8 project authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
4
5 #include "src/v8.h"
6
7 #include "src/lithium-codegen.h"
8
9 #if V8_TARGET_ARCH_IA32
10 #include "src/ia32/lithium-ia32.h" // NOLINT
11 #include "src/ia32/lithium-codegen-ia32.h" // NOLINT
12 #elif V8_TARGET_ARCH_X64
13 #include "src/x64/lithium-x64.h" // NOLINT
14 #include "src/x64/lithium-codegen-x64.h" // NOLINT
15 #elif V8_TARGET_ARCH_ARM
16 #include "src/arm/lithium-arm.h" // NOLINT
17 #include "src/arm/lithium-codegen-arm.h" // NOLINT
18 #elif V8_TARGET_ARCH_ARM64
19 #include "src/arm64/lithium-arm64.h" // NOLINT
20 #include "src/arm64/lithium-codegen-arm64.h" // NOLINT
21 #elif V8_TARGET_ARCH_MIPS
22 #include "src/mips/lithium-mips.h" // NOLINT
23 #include "src/mips/lithium-codegen-mips.h" // NOLINT
24 #elif V8_TARGET_ARCH_MIPS64
25 #include "src/mips64/lithium-mips64.h" // NOLINT
26 #include "src/mips64/lithium-codegen-mips64.h" // NOLINT
27 #elif V8_TARGET_ARCH_X87
28 #include "src/x87/lithium-x87.h" // NOLINT
29 #include "src/x87/lithium-codegen-x87.h" // NOLINT
30 #else
31 #error Unsupported target architecture.
32 #endif
33
34 namespace v8 {
35 namespace internal {
36
37
graph() const38 HGraph* LCodeGenBase::graph() const {
39 return chunk()->graph();
40 }
41
42
LCodeGenBase(LChunk * chunk,MacroAssembler * assembler,CompilationInfo * info)43 LCodeGenBase::LCodeGenBase(LChunk* chunk,
44 MacroAssembler* assembler,
45 CompilationInfo* info)
46 : chunk_(static_cast<LPlatformChunk*>(chunk)),
47 masm_(assembler),
48 info_(info),
49 zone_(info->zone()),
50 status_(UNUSED),
51 current_block_(-1),
52 current_instruction_(-1),
53 instructions_(chunk->instructions()),
54 last_lazy_deopt_pc_(0) {
55 }
56
57
GenerateBody()58 bool LCodeGenBase::GenerateBody() {
59 DCHECK(is_generating());
60 bool emit_instructions = true;
61 LCodeGen* codegen = static_cast<LCodeGen*>(this);
62 for (current_instruction_ = 0;
63 !is_aborted() && current_instruction_ < instructions_->length();
64 current_instruction_++) {
65 LInstruction* instr = instructions_->at(current_instruction_);
66
67 // Don't emit code for basic blocks with a replacement.
68 if (instr->IsLabel()) {
69 emit_instructions = !LLabel::cast(instr)->HasReplacement() &&
70 (!FLAG_unreachable_code_elimination ||
71 instr->hydrogen_value()->block()->IsReachable());
72 if (FLAG_code_comments && !emit_instructions) {
73 Comment(
74 ";;; <@%d,#%d> -------------------- B%d (unreachable/replaced) "
75 "--------------------",
76 current_instruction_,
77 instr->hydrogen_value()->id(),
78 instr->hydrogen_value()->block()->block_id());
79 }
80 }
81 if (!emit_instructions) continue;
82
83 if (FLAG_code_comments && instr->HasInterestingComment(codegen)) {
84 Comment(";;; <@%d,#%d> %s",
85 current_instruction_,
86 instr->hydrogen_value()->id(),
87 instr->Mnemonic());
88 }
89
90 GenerateBodyInstructionPre(instr);
91
92 HValue* value = instr->hydrogen_value();
93 if (!value->position().IsUnknown()) {
94 RecordAndWritePosition(
95 chunk()->graph()->SourcePositionToScriptPosition(value->position()));
96 }
97
98 instr->CompileToNative(codegen);
99
100 GenerateBodyInstructionPost(instr);
101 }
102 EnsureSpaceForLazyDeopt(Deoptimizer::patch_size());
103 last_lazy_deopt_pc_ = masm()->pc_offset();
104 return !is_aborted();
105 }
106
107
CheckEnvironmentUsage()108 void LCodeGenBase::CheckEnvironmentUsage() {
109 #ifdef DEBUG
110 bool dead_block = false;
111 for (int i = 0; i < instructions_->length(); i++) {
112 LInstruction* instr = instructions_->at(i);
113 HValue* hval = instr->hydrogen_value();
114 if (instr->IsLabel()) dead_block = LLabel::cast(instr)->HasReplacement();
115 if (dead_block || !hval->block()->IsReachable()) continue;
116
117 HInstruction* hinstr = HInstruction::cast(hval);
118 if (!hinstr->CanDeoptimize() && instr->HasEnvironment()) {
119 V8_Fatal(__FILE__, __LINE__, "CanDeoptimize is wrong for %s (%s)",
120 hinstr->Mnemonic(), instr->Mnemonic());
121 }
122
123 if (instr->HasEnvironment() && !instr->environment()->has_been_used()) {
124 V8_Fatal(__FILE__, __LINE__, "unused environment for %s (%s)",
125 hinstr->Mnemonic(), instr->Mnemonic());
126 }
127 }
128 #endif
129 }
130
131
Comment(const char * format,...)132 void LCodeGenBase::Comment(const char* format, ...) {
133 if (!FLAG_code_comments) return;
134 char buffer[4 * KB];
135 StringBuilder builder(buffer, arraysize(buffer));
136 va_list arguments;
137 va_start(arguments, format);
138 builder.AddFormattedList(format, arguments);
139 va_end(arguments);
140
141 // Copy the string before recording it in the assembler to avoid
142 // issues when the stack allocated buffer goes out of scope.
143 size_t length = builder.position();
144 Vector<char> copy = Vector<char>::New(static_cast<int>(length) + 1);
145 MemCopy(copy.start(), builder.Finalize(), copy.length());
146 masm()->RecordComment(copy.start());
147 }
148
149
DeoptComment(const Deoptimizer::Reason & reason)150 void LCodeGenBase::DeoptComment(const Deoptimizer::Reason& reason) {
151 OStringStream os;
152 os << ";;; deoptimize at " << HSourcePosition(reason.raw_position) << " "
153 << reason.mnemonic;
154 if (reason.detail != NULL) os << ": " << reason.detail;
155 Comment("%s", os.c_str());
156 }
157
158
GetNextEmittedBlock() const159 int LCodeGenBase::GetNextEmittedBlock() const {
160 for (int i = current_block_ + 1; i < graph()->blocks()->length(); ++i) {
161 if (!graph()->blocks()->at(i)->IsReachable()) continue;
162 if (!chunk_->GetLabel(i)->HasReplacement()) return i;
163 }
164 return -1;
165 }
166
167
AddWeakObjectToCodeDependency(Isolate * isolate,Handle<Object> object,Handle<Code> code)168 static void AddWeakObjectToCodeDependency(Isolate* isolate,
169 Handle<Object> object,
170 Handle<Code> code) {
171 Heap* heap = isolate->heap();
172 heap->EnsureWeakObjectToCodeTable();
173 Handle<DependentCode> dep(heap->LookupWeakObjectToCodeDependency(object));
174 dep = DependentCode::Insert(dep, DependentCode::kWeakCodeGroup, code);
175 heap->AddWeakObjectToCodeDependency(object, dep);
176 }
177
178
RegisterWeakObjectsInOptimizedCode(Handle<Code> code)179 void LCodeGenBase::RegisterWeakObjectsInOptimizedCode(Handle<Code> code) {
180 DCHECK(code->is_optimized_code());
181 ZoneList<Handle<Map> > maps(1, zone());
182 ZoneList<Handle<JSObject> > objects(1, zone());
183 ZoneList<Handle<Cell> > cells(1, zone());
184 int mode_mask = RelocInfo::ModeMask(RelocInfo::EMBEDDED_OBJECT) |
185 RelocInfo::ModeMask(RelocInfo::CELL);
186 for (RelocIterator it(*code, mode_mask); !it.done(); it.next()) {
187 RelocInfo::Mode mode = it.rinfo()->rmode();
188 if (mode == RelocInfo::CELL &&
189 code->IsWeakObjectInOptimizedCode(it.rinfo()->target_cell())) {
190 Handle<Cell> cell(it.rinfo()->target_cell());
191 cells.Add(cell, zone());
192 } else if (mode == RelocInfo::EMBEDDED_OBJECT &&
193 code->IsWeakObjectInOptimizedCode(it.rinfo()->target_object())) {
194 if (it.rinfo()->target_object()->IsMap()) {
195 Handle<Map> map(Map::cast(it.rinfo()->target_object()));
196 maps.Add(map, zone());
197 } else if (it.rinfo()->target_object()->IsJSObject()) {
198 Handle<JSObject> object(JSObject::cast(it.rinfo()->target_object()));
199 objects.Add(object, zone());
200 } else if (it.rinfo()->target_object()->IsCell()) {
201 Handle<Cell> cell(Cell::cast(it.rinfo()->target_object()));
202 cells.Add(cell, zone());
203 }
204 }
205 }
206 if (FLAG_enable_ool_constant_pool) {
207 code->constant_pool()->set_weak_object_state(
208 ConstantPoolArray::WEAK_OBJECTS_IN_OPTIMIZED_CODE);
209 }
210 #ifdef VERIFY_HEAP
211 // This disables verification of weak embedded objects after full GC.
212 // AddDependentCode can cause a GC, which would observe the state where
213 // this code is not yet in the depended code lists of the embedded maps.
214 NoWeakObjectVerificationScope disable_verification_of_embedded_objects;
215 #endif
216 for (int i = 0; i < maps.length(); i++) {
217 Map::AddDependentCode(maps.at(i), DependentCode::kWeakCodeGroup, code);
218 }
219 for (int i = 0; i < objects.length(); i++) {
220 AddWeakObjectToCodeDependency(isolate(), objects.at(i), code);
221 }
222 for (int i = 0; i < cells.length(); i++) {
223 AddWeakObjectToCodeDependency(isolate(), cells.at(i), code);
224 }
225 }
226
227
Abort(BailoutReason reason)228 void LCodeGenBase::Abort(BailoutReason reason) {
229 info()->AbortOptimization(reason);
230 status_ = ABORTED;
231 }
232
233
Retry(BailoutReason reason)234 void LCodeGenBase::Retry(BailoutReason reason) {
235 info()->RetryOptimization(reason);
236 status_ = ABORTED;
237 }
238
239
AddDeprecationDependency(Handle<Map> map)240 void LCodeGenBase::AddDeprecationDependency(Handle<Map> map) {
241 if (map->is_deprecated()) return Retry(kMapBecameDeprecated);
242 chunk_->AddDeprecationDependency(map);
243 }
244
245
AddStabilityDependency(Handle<Map> map)246 void LCodeGenBase::AddStabilityDependency(Handle<Map> map) {
247 if (!map->is_stable()) return Retry(kMapBecameUnstable);
248 chunk_->AddStabilityDependency(map);
249 }
250
251 } } // namespace v8::internal
252