1// Copyright 2012 the V8 project authors. All rights reserved.
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3// modification, are permitted provided that the following conditions are
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15//
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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 = pc() - Assembler::kCallTargetAddressOffset;
44
45#ifdef ENABLE_DEBUGGER_SUPPORT
46  Debug* debug = Isolate::Current()->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  Code* old_target = GetTargetAtAddress(address);
83#ifdef DEBUG
84  // STORE_IC and KEYED_STORE_IC use Code::extra_ic_state() to mark
85  // ICs as strict mode. The strict-ness of the IC must be preserved.
86  if (old_target->kind() == Code::STORE_IC ||
87      old_target->kind() == Code::KEYED_STORE_IC) {
88    ASSERT(Code::GetStrictMode(old_target->extra_ic_state()) ==
89           Code::GetStrictMode(target->extra_ic_state()));
90  }
91#endif
92  Assembler::set_target_address_at(address, target->instruction_start());
93  target->GetHeap()->incremental_marking()->RecordCodeTargetPatch(address,
94                                                                  target);
95  PostPatching(address, target, old_target);
96}
97
98
99InlineCacheHolderFlag IC::GetCodeCacheForObject(Object* object,
100                                                JSObject* holder) {
101  if (object->IsJSObject()) {
102    return GetCodeCacheForObject(JSObject::cast(object), holder);
103  }
104  // If the object is a value, we use the prototype map for the cache.
105  ASSERT(object->IsString() || object->IsNumber() || object->IsBoolean());
106  return PROTOTYPE_MAP;
107}
108
109
110InlineCacheHolderFlag IC::GetCodeCacheForObject(JSObject* object,
111                                                JSObject* holder) {
112  // Fast-properties and global objects store stubs in their own maps.
113  // Slow properties objects use prototype's map (unless the property is its own
114  // when holder == object). It works because slow properties objects having
115  // the same prototype (or a prototype with the same map) and not having
116  // the property are interchangeable for such a stub.
117  if (holder != object &&
118      !object->HasFastProperties() &&
119      !object->IsJSGlobalProxy() &&
120      !object->IsJSGlobalObject()) {
121    return PROTOTYPE_MAP;
122  }
123  return OWN_MAP;
124}
125
126
127JSObject* IC::GetCodeCacheHolder(Object* object, InlineCacheHolderFlag holder) {
128  Object* map_owner = (holder == OWN_MAP ? object : object->GetPrototype());
129  ASSERT(map_owner->IsJSObject());
130  return JSObject::cast(map_owner);
131}
132
133
134} }  // namespace v8::internal
135
136#endif  // V8_IC_INL_H_
137