1 // Copyright 2012 the V8 project authors. All rights reserved. 2 // Redistribution and use in source and binary forms, with or without 3 // modification, are permitted provided that the following conditions are 4 // met: 5 // 6 // * Redistributions of source code must retain the above copyright 7 // notice, this list of conditions and the following disclaimer. 8 // * Redistributions in binary form must reproduce the above 9 // copyright notice, this list of conditions and the following 10 // disclaimer in the documentation and/or other materials provided 11 // with the distribution. 12 // * Neither the name of Google Inc. nor the names of its 13 // contributors may be used to endorse or promote products derived 14 // from this software without specific prior written permission. 15 // 16 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 17 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 18 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 19 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 20 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 21 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 22 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 23 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 24 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 25 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 26 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 27 28 #include "v8.h" 29 30 #include "interface.h" 31 32 namespace v8 { 33 namespace internal { 34 35 static bool Match(void* key1, void* key2) { 36 String* name1 = *static_cast<String**>(key1); 37 String* name2 = *static_cast<String**>(key2); 38 ASSERT(name1->IsSymbol()); 39 ASSERT(name2->IsSymbol()); 40 return name1 == name2; 41 } 42 43 44 Interface* Interface::Lookup(Handle<String> name) { 45 ASSERT(IsModule()); 46 ZoneHashMap* map = Chase()->exports_; 47 if (map == NULL) return NULL; 48 ZoneHashMap::Entry* p = map->Lookup(name.location(), name->Hash(), false); 49 if (p == NULL) return NULL; 50 ASSERT(*static_cast<String**>(p->key) == *name); 51 ASSERT(p->value != NULL); 52 return static_cast<Interface*>(p->value); 53 } 54 55 56 #ifdef DEBUG 57 // Current nesting depth for debug output. 58 class Nesting { 59 public: 60 Nesting() { current_ += 2; } 61 ~Nesting() { current_ -= 2; } 62 static int current() { return current_; } 63 private: 64 static int current_; 65 }; 66 67 int Nesting::current_ = 0; 68 #endif 69 70 71 void Interface::DoAdd( 72 void* name, uint32_t hash, Interface* interface, bool* ok) { 73 MakeModule(ok); 74 if (!*ok) return; 75 76 #ifdef DEBUG 77 if (FLAG_print_interface_details) { 78 PrintF("%*s# Adding...\n", Nesting::current(), ""); 79 PrintF("%*sthis = ", Nesting::current(), ""); 80 this->Print(Nesting::current()); 81 PrintF("%*s%s : ", Nesting::current(), "", 82 (*reinterpret_cast<String**>(name))->ToAsciiArray()); 83 interface->Print(Nesting::current()); 84 } 85 #endif 86 87 ZoneHashMap** map = &Chase()->exports_; 88 if (*map == NULL) *map = new ZoneHashMap(Match, 8); 89 90 ZoneHashMap::Entry* p = (*map)->Lookup(name, hash, !IsFrozen()); 91 if (p == NULL) { 92 // This didn't have name but was frozen already, that's an error. 93 *ok = false; 94 } else if (p->value == NULL) { 95 p->value = interface; 96 } else { 97 #ifdef DEBUG 98 Nesting nested; 99 #endif 100 reinterpret_cast<Interface*>(p->value)->Unify(interface, ok); 101 } 102 103 #ifdef DEBUG 104 if (FLAG_print_interface_details) { 105 PrintF("%*sthis' = ", Nesting::current(), ""); 106 this->Print(Nesting::current()); 107 PrintF("%*s# Added.\n", Nesting::current(), ""); 108 } 109 #endif 110 } 111 112 113 void Interface::Unify(Interface* that, bool* ok) { 114 if (this->forward_) return this->Chase()->Unify(that, ok); 115 if (that->forward_) return this->Unify(that->Chase(), ok); 116 ASSERT(this->forward_ == NULL); 117 ASSERT(that->forward_ == NULL); 118 119 *ok = true; 120 if (this == that) return; 121 if (this->IsValue()) return that->MakeValue(ok); 122 if (that->IsValue()) return this->MakeValue(ok); 123 124 #ifdef DEBUG 125 if (FLAG_print_interface_details) { 126 PrintF("%*s# Unifying...\n", Nesting::current(), ""); 127 PrintF("%*sthis = ", Nesting::current(), ""); 128 this->Print(Nesting::current()); 129 PrintF("%*sthat = ", Nesting::current(), ""); 130 that->Print(Nesting::current()); 131 } 132 #endif 133 134 // Merge the smaller interface into the larger, for performance. 135 if (this->exports_ != NULL && (that->exports_ == NULL || 136 this->exports_->occupancy() >= that->exports_->occupancy())) { 137 this->DoUnify(that, ok); 138 } else { 139 that->DoUnify(this, ok); 140 } 141 142 #ifdef DEBUG 143 if (FLAG_print_interface_details) { 144 PrintF("%*sthis' = ", Nesting::current(), ""); 145 this->Print(Nesting::current()); 146 PrintF("%*sthat' = ", Nesting::current(), ""); 147 that->Print(Nesting::current()); 148 PrintF("%*s# Unified.\n", Nesting::current(), ""); 149 } 150 #endif 151 } 152 153 154 void Interface::DoUnify(Interface* that, bool* ok) { 155 ASSERT(this->forward_ == NULL); 156 ASSERT(that->forward_ == NULL); 157 ASSERT(!this->IsValue()); 158 ASSERT(!that->IsValue()); 159 ASSERT(*ok); 160 161 #ifdef DEBUG 162 Nesting nested; 163 #endif 164 165 // Try to merge all members from that into this. 166 ZoneHashMap* map = that->exports_; 167 if (map != NULL) { 168 for (ZoneHashMap::Entry* p = map->Start(); p != NULL; p = map->Next(p)) { 169 this->DoAdd(p->key, p->hash, static_cast<Interface*>(p->value), ok); 170 if (!*ok) return; 171 } 172 } 173 174 // If the new interface is larger than that's, then there were members in 175 // 'this' which 'that' didn't have. If 'that' was frozen that is an error. 176 int this_size = this->exports_ == NULL ? 0 : this->exports_->occupancy(); 177 int that_size = map == NULL ? 0 : map->occupancy(); 178 if (that->IsFrozen() && this_size > that_size) { 179 *ok = false; 180 return; 181 } 182 183 // Merge interfaces. 184 this->flags_ |= that->flags_; 185 that->forward_ = this; 186 } 187 188 189 #ifdef DEBUG 190 void Interface::Print(int n) { 191 int n0 = n > 0 ? n : 0; 192 193 if (FLAG_print_interface_details) { 194 PrintF("%p", static_cast<void*>(this)); 195 for (Interface* link = this->forward_; link != NULL; link = link->forward_) 196 PrintF("->%p", static_cast<void*>(link)); 197 PrintF(" "); 198 } 199 200 if (IsUnknown()) { 201 PrintF("unknown\n"); 202 } else if (IsValue()) { 203 PrintF("value\n"); 204 } else if (IsModule()) { 205 PrintF("module %s{", IsFrozen() ? "" : "(unresolved) "); 206 ZoneHashMap* map = Chase()->exports_; 207 if (map == NULL || map->occupancy() == 0) { 208 PrintF("}\n"); 209 } else if (n < 0 || n0 >= 2 * FLAG_print_interface_depth) { 210 // Avoid infinite recursion on cyclic types. 211 PrintF("...}\n"); 212 } else { 213 PrintF("\n"); 214 for (ZoneHashMap::Entry* p = map->Start(); p != NULL; p = map->Next(p)) { 215 String* name = *static_cast<String**>(p->key); 216 Interface* interface = static_cast<Interface*>(p->value); 217 PrintF("%*s%s : ", n0 + 2, "", name->ToAsciiArray()); 218 interface->Print(n0 + 2); 219 } 220 PrintF("%*s}\n", n0, ""); 221 } 222 } 223 } 224 #endif 225 226 } } // namespace v8::internal 227
