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27
28#ifndef V8_IC_INL_H_
29#define V8_IC_INL_H_
30
31#include "ic.h"
32
33#include "compiler.h"
34#include "debug.h"
35#include "macro-assembler.h"
36
37namespace v8 {
38namespace internal {
39
40
41Address IC::address() const {
42  // Get the address of the call.
43  Address result = Assembler::target_address_from_return_address(pc());
44
45#ifdef ENABLE_DEBUGGER_SUPPORT
46  Debug* debug = isolate()->debug();
47  // First check if any break points are active if not just return the address
48  // of the call.
49  if (!debug->has_break_points()) return result;
50
51  // At least one break point is active perform additional test to ensure that
52  // break point locations are updated correctly.
53  if (debug->IsDebugBreak(Assembler::target_address_at(result))) {
54    // If the call site is a call to debug break then return the address in
55    // the original code instead of the address in the running code. This will
56    // cause the original code to be updated and keeps the breakpoint active in
57    // the running code.
58    return OriginalCodeAddress();
59  } else {
60    // No break point here just return the address of the call.
61    return result;
62  }
63#else
64  return result;
65#endif
66}
67
68
69Code* IC::GetTargetAtAddress(Address address) {
70  // Get the target address of the IC.
71  Address target = Assembler::target_address_at(address);
72  // Convert target address to the code object. Code::GetCodeFromTargetAddress
73  // is safe for use during GC where the map might be marked.
74  Code* result = Code::GetCodeFromTargetAddress(target);
75  ASSERT(result->is_inline_cache_stub());
76  return result;
77}
78
79
80void IC::SetTargetAtAddress(Address address, Code* target) {
81  ASSERT(target->is_inline_cache_stub() || target->is_compare_ic_stub());
82  Heap* heap = target->GetHeap();
83  Code* old_target = GetTargetAtAddress(address);
84#ifdef DEBUG
85  // STORE_IC and KEYED_STORE_IC use Code::extra_ic_state() to mark
86  // ICs as strict mode. The strict-ness of the IC must be preserved.
87  if (old_target->kind() == Code::STORE_IC ||
88      old_target->kind() == Code::KEYED_STORE_IC) {
89    ASSERT(StoreIC::GetStrictMode(old_target->extra_ic_state()) ==
90           StoreIC::GetStrictMode(target->extra_ic_state()));
91  }
92#endif
93  Assembler::set_target_address_at(address, target->instruction_start());
94  if (heap->gc_state() == Heap::MARK_COMPACT) {
95    heap->mark_compact_collector()->RecordCodeTargetPatch(address, target);
96  } else {
97    heap->incremental_marking()->RecordCodeTargetPatch(address, target);
98  }
99  PostPatching(address, target, old_target);
100}
101
102
103InlineCacheHolderFlag IC::GetCodeCacheForObject(Object* object) {
104  if (object->IsJSObject()) return OWN_MAP;
105
106  // If the object is a value, we use the prototype map for the cache.
107  ASSERT(object->IsString() || object->IsSymbol() ||
108         object->IsNumber() || object->IsBoolean());
109  return PROTOTYPE_MAP;
110}
111
112
113HeapObject* IC::GetCodeCacheHolder(Isolate* isolate,
114                                 Object* object,
115                                 InlineCacheHolderFlag holder) {
116  if (object->IsSmi()) holder = PROTOTYPE_MAP;
117  Object* map_owner = holder == OWN_MAP
118      ? object : object->GetPrototype(isolate);
119  return HeapObject::cast(map_owner);
120}
121
122
123InlineCacheHolderFlag IC::GetCodeCacheFlag(Type* type) {
124  if (type->Is(Type::Boolean()) ||
125      type->Is(Type::Number()) ||
126      type->Is(Type::String()) ||
127      type->Is(Type::Symbol())) {
128    return PROTOTYPE_MAP;
129  }
130  return OWN_MAP;
131}
132
133
134Handle<Map> IC::GetCodeCacheHolder(InlineCacheHolderFlag flag,
135                                   Type* type,
136                                   Isolate* isolate) {
137  if (flag == PROTOTYPE_MAP) {
138    Context* context = isolate->context()->native_context();
139    JSFunction* constructor;
140    if (type->Is(Type::Boolean())) {
141      constructor = context->boolean_function();
142    } else if (type->Is(Type::Number())) {
143      constructor = context->number_function();
144    } else if (type->Is(Type::String())) {
145      constructor = context->string_function();
146    } else {
147      ASSERT(type->Is(Type::Symbol()));
148      constructor = context->symbol_function();
149    }
150    return handle(JSObject::cast(constructor->instance_prototype())->map());
151  }
152  return TypeToMap(type, isolate);
153}
154
155
156} }  // namespace v8::internal
157
158#endif  // V8_IC_INL_H_
159