1 // Copyright 2014 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/ic/call-optimization.h"
8 #include "src/ic/handler-compiler.h"
9 #include "src/ic/ic.h"
10 #include "src/ic/ic-inl.h"
11 
12 namespace v8 {
13 namespace internal {
14 
15 
Find(Handle<Name> name,Handle<Map> stub_holder,Code::Kind kind,CacheHolderFlag cache_holder,Code::StubType type)16 Handle<Code> PropertyHandlerCompiler::Find(Handle<Name> name,
17                                            Handle<Map> stub_holder,
18                                            Code::Kind kind,
19                                            CacheHolderFlag cache_holder,
20                                            Code::StubType type) {
21   Code::Flags flags = Code::ComputeHandlerFlags(kind, type, cache_holder);
22   Object* probe = stub_holder->FindInCodeCache(*name, flags);
23   if (probe->IsCode()) return handle(Code::cast(probe));
24   return Handle<Code>::null();
25 }
26 
27 
ComputeLoadNonexistent(Handle<Name> name,Handle<HeapType> type)28 Handle<Code> NamedLoadHandlerCompiler::ComputeLoadNonexistent(
29     Handle<Name> name, Handle<HeapType> type) {
30   Isolate* isolate = name->GetIsolate();
31   Handle<Map> receiver_map = IC::TypeToMap(*type, isolate);
32   if (receiver_map->prototype()->IsNull()) {
33     // TODO(jkummerow/verwaest): If there is no prototype and the property
34     // is nonexistent, introduce a builtin to handle this (fast properties
35     // -> return undefined, dictionary properties -> do negative lookup).
36     return Handle<Code>();
37   }
38   CacheHolderFlag flag;
39   Handle<Map> stub_holder_map =
40       IC::GetHandlerCacheHolder(*type, false, isolate, &flag);
41 
42   // If no dictionary mode objects are present in the prototype chain, the load
43   // nonexistent IC stub can be shared for all names for a given map and we use
44   // the empty string for the map cache in that case. If there are dictionary
45   // mode objects involved, we need to do negative lookups in the stub and
46   // therefore the stub will be specific to the name.
47   Handle<Name> cache_name =
48       receiver_map->is_dictionary_map()
49           ? name
50           : Handle<Name>::cast(isolate->factory()->nonexistent_symbol());
51   Handle<Map> current_map = stub_holder_map;
52   Handle<JSObject> last(JSObject::cast(receiver_map->prototype()));
53   while (true) {
54     if (current_map->is_dictionary_map()) cache_name = name;
55     if (current_map->prototype()->IsNull()) break;
56     last = handle(JSObject::cast(current_map->prototype()));
57     current_map = handle(last->map());
58   }
59   // Compile the stub that is either shared for all names or
60   // name specific if there are global objects involved.
61   Handle<Code> handler = PropertyHandlerCompiler::Find(
62       cache_name, stub_holder_map, Code::LOAD_IC, flag, Code::FAST);
63   if (!handler.is_null()) return handler;
64 
65   NamedLoadHandlerCompiler compiler(isolate, type, last, flag);
66   handler = compiler.CompileLoadNonexistent(cache_name);
67   Map::UpdateCodeCache(stub_holder_map, cache_name, handler);
68   return handler;
69 }
70 
71 
GetCode(Code::Kind kind,Code::StubType type,Handle<Name> name)72 Handle<Code> PropertyHandlerCompiler::GetCode(Code::Kind kind,
73                                               Code::StubType type,
74                                               Handle<Name> name) {
75   Code::Flags flags = Code::ComputeHandlerFlags(kind, type, cache_holder());
76   Handle<Code> code = GetCodeWithFlags(flags, name);
77   PROFILE(isolate(), CodeCreateEvent(Logger::STUB_TAG, *code, *name));
78   return code;
79 }
80 
81 
set_type_for_object(Handle<Object> object)82 void PropertyHandlerCompiler::set_type_for_object(Handle<Object> object) {
83   type_ = IC::CurrentTypeOf(object, isolate());
84 }
85 
86 
87 #define __ ACCESS_MASM(masm())
88 
89 
FrontendHeader(Register object_reg,Handle<Name> name,Label * miss)90 Register NamedLoadHandlerCompiler::FrontendHeader(Register object_reg,
91                                                   Handle<Name> name,
92                                                   Label* miss) {
93   PrototypeCheckType check_type = CHECK_ALL_MAPS;
94   int function_index = -1;
95   if (type()->Is(HeapType::String())) {
96     function_index = Context::STRING_FUNCTION_INDEX;
97   } else if (type()->Is(HeapType::Symbol())) {
98     function_index = Context::SYMBOL_FUNCTION_INDEX;
99   } else if (type()->Is(HeapType::Number())) {
100     function_index = Context::NUMBER_FUNCTION_INDEX;
101   } else if (type()->Is(HeapType::Boolean())) {
102     function_index = Context::BOOLEAN_FUNCTION_INDEX;
103   } else {
104     check_type = SKIP_RECEIVER;
105   }
106 
107   if (check_type == CHECK_ALL_MAPS) {
108     GenerateDirectLoadGlobalFunctionPrototype(masm(), function_index,
109                                               scratch1(), miss);
110     Object* function = isolate()->native_context()->get(function_index);
111     Object* prototype = JSFunction::cast(function)->instance_prototype();
112     set_type_for_object(handle(prototype, isolate()));
113     object_reg = scratch1();
114   }
115 
116   // Check that the maps starting from the prototype haven't changed.
117   return CheckPrototypes(object_reg, scratch1(), scratch2(), scratch3(), name,
118                          miss, check_type);
119 }
120 
121 
122 // Frontend for store uses the name register. It has to be restored before a
123 // miss.
FrontendHeader(Register object_reg,Handle<Name> name,Label * miss)124 Register NamedStoreHandlerCompiler::FrontendHeader(Register object_reg,
125                                                    Handle<Name> name,
126                                                    Label* miss) {
127   return CheckPrototypes(object_reg, this->name(), scratch1(), scratch2(), name,
128                          miss, SKIP_RECEIVER);
129 }
130 
131 
Frontend(Register object_reg,Handle<Name> name)132 Register PropertyHandlerCompiler::Frontend(Register object_reg,
133                                            Handle<Name> name) {
134   Label miss;
135   Register reg = FrontendHeader(object_reg, name, &miss);
136   FrontendFooter(name, &miss);
137   return reg;
138 }
139 
140 
NonexistentFrontendHeader(Handle<Name> name,Label * miss,Register scratch1,Register scratch2)141 void PropertyHandlerCompiler::NonexistentFrontendHeader(Handle<Name> name,
142                                                         Label* miss,
143                                                         Register scratch1,
144                                                         Register scratch2) {
145   Register holder_reg;
146   Handle<Map> last_map;
147   if (holder().is_null()) {
148     holder_reg = receiver();
149     last_map = IC::TypeToMap(*type(), isolate());
150     // If |type| has null as its prototype, |holder()| is
151     // Handle<JSObject>::null().
152     DCHECK(last_map->prototype() == isolate()->heap()->null_value());
153   } else {
154     holder_reg = FrontendHeader(receiver(), name, miss);
155     last_map = handle(holder()->map());
156   }
157 
158   if (last_map->is_dictionary_map()) {
159     if (last_map->IsJSGlobalObjectMap()) {
160       Handle<JSGlobalObject> global =
161           holder().is_null()
162               ? Handle<JSGlobalObject>::cast(type()->AsConstant()->Value())
163               : Handle<JSGlobalObject>::cast(holder());
164       GenerateCheckPropertyCell(masm(), global, name, scratch1, miss);
165     } else {
166       if (!name->IsUniqueName()) {
167         DCHECK(name->IsString());
168         name = factory()->InternalizeString(Handle<String>::cast(name));
169       }
170       DCHECK(holder().is_null() ||
171              holder()->property_dictionary()->FindEntry(name) ==
172                  NameDictionary::kNotFound);
173       GenerateDictionaryNegativeLookup(masm(), miss, holder_reg, name, scratch1,
174                                        scratch2);
175     }
176   }
177 }
178 
179 
CompileLoadField(Handle<Name> name,FieldIndex field)180 Handle<Code> NamedLoadHandlerCompiler::CompileLoadField(Handle<Name> name,
181                                                         FieldIndex field) {
182   Register reg = Frontend(receiver(), name);
183   __ Move(receiver(), reg);
184   LoadFieldStub stub(isolate(), field);
185   GenerateTailCall(masm(), stub.GetCode());
186   return GetCode(kind(), Code::FAST, name);
187 }
188 
189 
CompileLoadConstant(Handle<Name> name,int constant_index)190 Handle<Code> NamedLoadHandlerCompiler::CompileLoadConstant(Handle<Name> name,
191                                                            int constant_index) {
192   Register reg = Frontend(receiver(), name);
193   __ Move(receiver(), reg);
194   LoadConstantStub stub(isolate(), constant_index);
195   GenerateTailCall(masm(), stub.GetCode());
196   return GetCode(kind(), Code::FAST, name);
197 }
198 
199 
CompileLoadNonexistent(Handle<Name> name)200 Handle<Code> NamedLoadHandlerCompiler::CompileLoadNonexistent(
201     Handle<Name> name) {
202   Label miss;
203   NonexistentFrontendHeader(name, &miss, scratch2(), scratch3());
204   GenerateLoadConstant(isolate()->factory()->undefined_value());
205   FrontendFooter(name, &miss);
206   return GetCode(kind(), Code::FAST, name);
207 }
208 
209 
CompileLoadCallback(Handle<Name> name,Handle<ExecutableAccessorInfo> callback)210 Handle<Code> NamedLoadHandlerCompiler::CompileLoadCallback(
211     Handle<Name> name, Handle<ExecutableAccessorInfo> callback) {
212   Register reg = Frontend(receiver(), name);
213   GenerateLoadCallback(reg, callback);
214   return GetCode(kind(), Code::FAST, name);
215 }
216 
217 
CompileLoadCallback(Handle<Name> name,const CallOptimization & call_optimization)218 Handle<Code> NamedLoadHandlerCompiler::CompileLoadCallback(
219     Handle<Name> name, const CallOptimization& call_optimization) {
220   DCHECK(call_optimization.is_simple_api_call());
221   Frontend(receiver(), name);
222   Handle<Map> receiver_map = IC::TypeToMap(*type(), isolate());
223   GenerateFastApiCall(masm(), call_optimization, receiver_map, receiver(),
224                       scratch1(), false, 0, NULL);
225   return GetCode(kind(), Code::FAST, name);
226 }
227 
228 
CompileLoadInterceptor(LookupIterator * it)229 Handle<Code> NamedLoadHandlerCompiler::CompileLoadInterceptor(
230     LookupIterator* it) {
231   // So far the most popular follow ups for interceptor loads are FIELD and
232   // ExecutableAccessorInfo, so inline only them. Other cases may be added
233   // later.
234   bool inline_followup = false;
235   switch (it->state()) {
236     case LookupIterator::TRANSITION:
237       UNREACHABLE();
238     case LookupIterator::ACCESS_CHECK:
239     case LookupIterator::INTERCEPTOR:
240     case LookupIterator::JSPROXY:
241     case LookupIterator::NOT_FOUND:
242       break;
243     case LookupIterator::DATA:
244       inline_followup = it->property_details().type() == FIELD;
245       break;
246     case LookupIterator::ACCESSOR: {
247       Handle<Object> accessors = it->GetAccessors();
248       inline_followup = accessors->IsExecutableAccessorInfo();
249       if (!inline_followup) break;
250       Handle<ExecutableAccessorInfo> info =
251           Handle<ExecutableAccessorInfo>::cast(accessors);
252       inline_followup = info->getter() != NULL &&
253                         ExecutableAccessorInfo::IsCompatibleReceiverType(
254                             isolate(), info, type());
255     }
256   }
257 
258   Register reg = Frontend(receiver(), it->name());
259   if (inline_followup) {
260     // TODO(368): Compile in the whole chain: all the interceptors in
261     // prototypes and ultimate answer.
262     GenerateLoadInterceptorWithFollowup(it, reg);
263   } else {
264     GenerateLoadInterceptor(reg);
265   }
266   return GetCode(kind(), Code::FAST, it->name());
267 }
268 
269 
GenerateLoadPostInterceptor(LookupIterator * it,Register interceptor_reg)270 void NamedLoadHandlerCompiler::GenerateLoadPostInterceptor(
271     LookupIterator* it, Register interceptor_reg) {
272   Handle<JSObject> real_named_property_holder(it->GetHolder<JSObject>());
273 
274   set_type_for_object(holder());
275   set_holder(real_named_property_holder);
276   Register reg = Frontend(interceptor_reg, it->name());
277 
278   switch (it->state()) {
279     case LookupIterator::ACCESS_CHECK:
280     case LookupIterator::INTERCEPTOR:
281     case LookupIterator::JSPROXY:
282     case LookupIterator::NOT_FOUND:
283     case LookupIterator::TRANSITION:
284       UNREACHABLE();
285     case LookupIterator::DATA: {
286       DCHECK_EQ(FIELD, it->property_details().type());
287       __ Move(receiver(), reg);
288       LoadFieldStub stub(isolate(), it->GetFieldIndex());
289       GenerateTailCall(masm(), stub.GetCode());
290       break;
291     }
292     case LookupIterator::ACCESSOR:
293       Handle<ExecutableAccessorInfo> info =
294           Handle<ExecutableAccessorInfo>::cast(it->GetAccessors());
295       DCHECK_NE(NULL, info->getter());
296       GenerateLoadCallback(reg, info);
297   }
298 }
299 
300 
CompileLoadViaGetter(Handle<Name> name,Handle<JSFunction> getter)301 Handle<Code> NamedLoadHandlerCompiler::CompileLoadViaGetter(
302     Handle<Name> name, Handle<JSFunction> getter) {
303   Frontend(receiver(), name);
304   GenerateLoadViaGetter(masm(), type(), receiver(), getter);
305   return GetCode(kind(), Code::FAST, name);
306 }
307 
308 
309 // TODO(verwaest): Cleanup. holder() is actually the receiver.
CompileStoreTransition(Handle<Map> transition,Handle<Name> name)310 Handle<Code> NamedStoreHandlerCompiler::CompileStoreTransition(
311     Handle<Map> transition, Handle<Name> name) {
312   Label miss, slow;
313 
314   // Ensure no transitions to deprecated maps are followed.
315   __ CheckMapDeprecated(transition, scratch1(), &miss);
316 
317   // Check that we are allowed to write this.
318   bool is_nonexistent = holder()->map() == transition->GetBackPointer();
319   if (is_nonexistent) {
320     // Find the top object.
321     Handle<JSObject> last;
322     PrototypeIterator iter(isolate(), holder());
323     while (!iter.IsAtEnd()) {
324       last = Handle<JSObject>::cast(PrototypeIterator::GetCurrent(iter));
325       iter.Advance();
326     }
327     if (!last.is_null()) set_holder(last);
328     NonexistentFrontendHeader(name, &miss, scratch1(), scratch2());
329   } else {
330     FrontendHeader(receiver(), name, &miss);
331     DCHECK(holder()->HasFastProperties());
332   }
333 
334   GenerateStoreTransition(transition, name, receiver(), this->name(), value(),
335                           scratch1(), scratch2(), scratch3(), &miss, &slow);
336 
337   GenerateRestoreName(&miss, name);
338   TailCallBuiltin(masm(), MissBuiltin(kind()));
339 
340   GenerateRestoreName(&slow, name);
341   TailCallBuiltin(masm(), SlowBuiltin(kind()));
342   return GetCode(kind(), Code::FAST, name);
343 }
344 
345 
CompileStoreField(LookupIterator * it)346 Handle<Code> NamedStoreHandlerCompiler::CompileStoreField(LookupIterator* it) {
347   Label miss;
348   GenerateStoreField(it, value(), &miss);
349   __ bind(&miss);
350   TailCallBuiltin(masm(), MissBuiltin(kind()));
351   return GetCode(kind(), Code::FAST, it->name());
352 }
353 
354 
CompileStoreViaSetter(Handle<JSObject> object,Handle<Name> name,Handle<JSFunction> setter)355 Handle<Code> NamedStoreHandlerCompiler::CompileStoreViaSetter(
356     Handle<JSObject> object, Handle<Name> name, Handle<JSFunction> setter) {
357   Frontend(receiver(), name);
358   GenerateStoreViaSetter(masm(), type(), receiver(), setter);
359 
360   return GetCode(kind(), Code::FAST, name);
361 }
362 
363 
CompileStoreCallback(Handle<JSObject> object,Handle<Name> name,const CallOptimization & call_optimization)364 Handle<Code> NamedStoreHandlerCompiler::CompileStoreCallback(
365     Handle<JSObject> object, Handle<Name> name,
366     const CallOptimization& call_optimization) {
367   Frontend(receiver(), name);
368   Register values[] = {value()};
369   GenerateFastApiCall(masm(), call_optimization, handle(object->map()),
370                       receiver(), scratch1(), true, 1, values);
371   return GetCode(kind(), Code::FAST, name);
372 }
373 
374 
375 #undef __
376 
377 
CompileElementHandlers(MapHandleList * receiver_maps,CodeHandleList * handlers)378 void ElementHandlerCompiler::CompileElementHandlers(
379     MapHandleList* receiver_maps, CodeHandleList* handlers) {
380   for (int i = 0; i < receiver_maps->length(); ++i) {
381     Handle<Map> receiver_map = receiver_maps->at(i);
382     Handle<Code> cached_stub;
383 
384     if ((receiver_map->instance_type() & kNotStringTag) == 0) {
385       cached_stub = isolate()->builtins()->KeyedLoadIC_String();
386     } else if (receiver_map->instance_type() < FIRST_JS_RECEIVER_TYPE) {
387       cached_stub = isolate()->builtins()->KeyedLoadIC_Slow();
388     } else {
389       bool is_js_array = receiver_map->instance_type() == JS_ARRAY_TYPE;
390       ElementsKind elements_kind = receiver_map->elements_kind();
391       if (receiver_map->has_indexed_interceptor()) {
392         cached_stub = LoadIndexedInterceptorStub(isolate()).GetCode();
393       } else if (IsSloppyArgumentsElements(elements_kind)) {
394         cached_stub = KeyedLoadSloppyArgumentsStub(isolate()).GetCode();
395       } else if (IsFastElementsKind(elements_kind) ||
396                  IsExternalArrayElementsKind(elements_kind) ||
397                  IsFixedTypedArrayElementsKind(elements_kind)) {
398         cached_stub = LoadFastElementStub(isolate(), is_js_array, elements_kind)
399                           .GetCode();
400       } else {
401         DCHECK(elements_kind == DICTIONARY_ELEMENTS);
402         cached_stub = LoadDictionaryElementStub(isolate()).GetCode();
403       }
404     }
405 
406     handlers->Add(cached_stub);
407   }
408 }
409 }
410 }  // namespace v8::internal
411