Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1 | // Copyright 2006-2008 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 | #ifndef V8_HEAP_H_ |
| 29 | #define V8_HEAP_H_ |
| 30 | |
| 31 | #include <math.h> |
| 32 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 33 | #include "splay-tree-inl.h" |
| 34 | #include "v8-counters.h" |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 35 | |
| 36 | namespace v8 { |
| 37 | namespace internal { |
| 38 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 39 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 40 | // Defines all the roots in Heap. |
| 41 | #define UNCONDITIONAL_STRONG_ROOT_LIST(V) \ |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 42 | /* Put the byte array map early. We need it to be in place by the time */ \ |
| 43 | /* the deserializer hits the next page, since it wants to put a byte */ \ |
| 44 | /* array in the unused space at the end of the page. */ \ |
| 45 | V(Map, byte_array_map, ByteArrayMap) \ |
| 46 | V(Map, one_pointer_filler_map, OnePointerFillerMap) \ |
| 47 | V(Map, two_pointer_filler_map, TwoPointerFillerMap) \ |
| 48 | /* Cluster the most popular ones in a few cache lines here at the top. */ \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 49 | V(Smi, stack_limit, StackLimit) \ |
| 50 | V(Object, undefined_value, UndefinedValue) \ |
| 51 | V(Object, the_hole_value, TheHoleValue) \ |
| 52 | V(Object, null_value, NullValue) \ |
| 53 | V(Object, true_value, TrueValue) \ |
| 54 | V(Object, false_value, FalseValue) \ |
| 55 | V(Map, heap_number_map, HeapNumberMap) \ |
| 56 | V(Map, global_context_map, GlobalContextMap) \ |
| 57 | V(Map, fixed_array_map, FixedArrayMap) \ |
| 58 | V(Object, no_interceptor_result_sentinel, NoInterceptorResultSentinel) \ |
| 59 | V(Map, meta_map, MetaMap) \ |
| 60 | V(Object, termination_exception, TerminationException) \ |
| 61 | V(Map, hash_table_map, HashTableMap) \ |
| 62 | V(FixedArray, empty_fixed_array, EmptyFixedArray) \ |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 63 | V(Map, string_map, StringMap) \ |
| 64 | V(Map, ascii_string_map, AsciiStringMap) \ |
| 65 | V(Map, symbol_map, SymbolMap) \ |
| 66 | V(Map, ascii_symbol_map, AsciiSymbolMap) \ |
| 67 | V(Map, cons_symbol_map, ConsSymbolMap) \ |
| 68 | V(Map, cons_ascii_symbol_map, ConsAsciiSymbolMap) \ |
| 69 | V(Map, external_symbol_map, ExternalSymbolMap) \ |
Kristian Monsen | 9dcf7e2 | 2010-06-28 14:14:28 +0100 | [diff] [blame] | 70 | V(Map, external_symbol_with_ascii_data_map, ExternalSymbolWithAsciiDataMap) \ |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 71 | V(Map, external_ascii_symbol_map, ExternalAsciiSymbolMap) \ |
| 72 | V(Map, cons_string_map, ConsStringMap) \ |
| 73 | V(Map, cons_ascii_string_map, ConsAsciiStringMap) \ |
| 74 | V(Map, external_string_map, ExternalStringMap) \ |
Kristian Monsen | 9dcf7e2 | 2010-06-28 14:14:28 +0100 | [diff] [blame] | 75 | V(Map, external_string_with_ascii_data_map, ExternalStringWithAsciiDataMap) \ |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 76 | V(Map, external_ascii_string_map, ExternalAsciiStringMap) \ |
| 77 | V(Map, undetectable_string_map, UndetectableStringMap) \ |
| 78 | V(Map, undetectable_ascii_string_map, UndetectableAsciiStringMap) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 79 | V(Map, pixel_array_map, PixelArrayMap) \ |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 80 | V(Map, external_byte_array_map, ExternalByteArrayMap) \ |
| 81 | V(Map, external_unsigned_byte_array_map, ExternalUnsignedByteArrayMap) \ |
| 82 | V(Map, external_short_array_map, ExternalShortArrayMap) \ |
| 83 | V(Map, external_unsigned_short_array_map, ExternalUnsignedShortArrayMap) \ |
| 84 | V(Map, external_int_array_map, ExternalIntArrayMap) \ |
| 85 | V(Map, external_unsigned_int_array_map, ExternalUnsignedIntArrayMap) \ |
| 86 | V(Map, external_float_array_map, ExternalFloatArrayMap) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 87 | V(Map, context_map, ContextMap) \ |
| 88 | V(Map, catch_context_map, CatchContextMap) \ |
| 89 | V(Map, code_map, CodeMap) \ |
| 90 | V(Map, oddball_map, OddballMap) \ |
| 91 | V(Map, global_property_cell_map, GlobalPropertyCellMap) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 92 | V(Map, shared_function_info_map, SharedFunctionInfoMap) \ |
| 93 | V(Map, proxy_map, ProxyMap) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 94 | V(Object, nan_value, NanValue) \ |
| 95 | V(Object, minus_zero_value, MinusZeroValue) \ |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 96 | V(Object, instanceof_cache_function, InstanceofCacheFunction) \ |
| 97 | V(Object, instanceof_cache_map, InstanceofCacheMap) \ |
| 98 | V(Object, instanceof_cache_answer, InstanceofCacheAnswer) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 99 | V(String, empty_string, EmptyString) \ |
| 100 | V(DescriptorArray, empty_descriptor_array, EmptyDescriptorArray) \ |
| 101 | V(Map, neander_map, NeanderMap) \ |
| 102 | V(JSObject, message_listeners, MessageListeners) \ |
| 103 | V(Proxy, prototype_accessors, PrototypeAccessors) \ |
| 104 | V(NumberDictionary, code_stubs, CodeStubs) \ |
| 105 | V(NumberDictionary, non_monomorphic_cache, NonMonomorphicCache) \ |
| 106 | V(Code, js_entry_code, JsEntryCode) \ |
| 107 | V(Code, js_construct_entry_code, JsConstructEntryCode) \ |
| 108 | V(Code, c_entry_code, CEntryCode) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 109 | V(FixedArray, number_string_cache, NumberStringCache) \ |
| 110 | V(FixedArray, single_character_string_cache, SingleCharacterStringCache) \ |
| 111 | V(FixedArray, natives_source_cache, NativesSourceCache) \ |
| 112 | V(Object, last_script_id, LastScriptId) \ |
Andrei Popescu | 3100271 | 2010-02-23 13:46:05 +0000 | [diff] [blame] | 113 | V(Script, empty_script, EmptyScript) \ |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 114 | V(Smi, real_stack_limit, RealStackLimit) \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 115 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 116 | #if V8_TARGET_ARCH_ARM && !V8_INTERPRETED_REGEXP |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 117 | #define STRONG_ROOT_LIST(V) \ |
| 118 | UNCONDITIONAL_STRONG_ROOT_LIST(V) \ |
| 119 | V(Code, re_c_entry_code, RegExpCEntryCode) |
| 120 | #else |
| 121 | #define STRONG_ROOT_LIST(V) UNCONDITIONAL_STRONG_ROOT_LIST(V) |
| 122 | #endif |
| 123 | |
| 124 | #define ROOT_LIST(V) \ |
| 125 | STRONG_ROOT_LIST(V) \ |
| 126 | V(SymbolTable, symbol_table, SymbolTable) |
| 127 | |
| 128 | #define SYMBOL_LIST(V) \ |
| 129 | V(Array_symbol, "Array") \ |
| 130 | V(Object_symbol, "Object") \ |
| 131 | V(Proto_symbol, "__proto__") \ |
| 132 | V(StringImpl_symbol, "StringImpl") \ |
| 133 | V(arguments_symbol, "arguments") \ |
| 134 | V(Arguments_symbol, "Arguments") \ |
| 135 | V(arguments_shadow_symbol, ".arguments") \ |
| 136 | V(call_symbol, "call") \ |
| 137 | V(apply_symbol, "apply") \ |
| 138 | V(caller_symbol, "caller") \ |
| 139 | V(boolean_symbol, "boolean") \ |
| 140 | V(Boolean_symbol, "Boolean") \ |
| 141 | V(callee_symbol, "callee") \ |
| 142 | V(constructor_symbol, "constructor") \ |
| 143 | V(code_symbol, ".code") \ |
| 144 | V(result_symbol, ".result") \ |
| 145 | V(catch_var_symbol, ".catch-var") \ |
| 146 | V(empty_symbol, "") \ |
| 147 | V(eval_symbol, "eval") \ |
| 148 | V(function_symbol, "function") \ |
| 149 | V(length_symbol, "length") \ |
| 150 | V(name_symbol, "name") \ |
| 151 | V(number_symbol, "number") \ |
| 152 | V(Number_symbol, "Number") \ |
| 153 | V(RegExp_symbol, "RegExp") \ |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 154 | V(source_symbol, "source") \ |
| 155 | V(global_symbol, "global") \ |
| 156 | V(ignore_case_symbol, "ignoreCase") \ |
| 157 | V(multiline_symbol, "multiline") \ |
| 158 | V(input_symbol, "input") \ |
| 159 | V(index_symbol, "index") \ |
| 160 | V(last_index_symbol, "lastIndex") \ |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 161 | V(object_symbol, "object") \ |
| 162 | V(prototype_symbol, "prototype") \ |
| 163 | V(string_symbol, "string") \ |
| 164 | V(String_symbol, "String") \ |
| 165 | V(Date_symbol, "Date") \ |
| 166 | V(this_symbol, "this") \ |
| 167 | V(to_string_symbol, "toString") \ |
| 168 | V(char_at_symbol, "CharAt") \ |
| 169 | V(undefined_symbol, "undefined") \ |
| 170 | V(value_of_symbol, "valueOf") \ |
| 171 | V(InitializeVarGlobal_symbol, "InitializeVarGlobal") \ |
| 172 | V(InitializeConstGlobal_symbol, "InitializeConstGlobal") \ |
| 173 | V(stack_overflow_symbol, "kStackOverflowBoilerplate") \ |
| 174 | V(illegal_access_symbol, "illegal access") \ |
| 175 | V(out_of_memory_symbol, "out-of-memory") \ |
| 176 | V(illegal_execution_state_symbol, "illegal execution state") \ |
| 177 | V(get_symbol, "get") \ |
| 178 | V(set_symbol, "set") \ |
| 179 | V(function_class_symbol, "Function") \ |
| 180 | V(illegal_argument_symbol, "illegal argument") \ |
| 181 | V(MakeReferenceError_symbol, "MakeReferenceError") \ |
| 182 | V(MakeSyntaxError_symbol, "MakeSyntaxError") \ |
| 183 | V(MakeTypeError_symbol, "MakeTypeError") \ |
| 184 | V(invalid_lhs_in_assignment_symbol, "invalid_lhs_in_assignment") \ |
| 185 | V(invalid_lhs_in_for_in_symbol, "invalid_lhs_in_for_in") \ |
| 186 | V(invalid_lhs_in_postfix_op_symbol, "invalid_lhs_in_postfix_op") \ |
| 187 | V(invalid_lhs_in_prefix_op_symbol, "invalid_lhs_in_prefix_op") \ |
| 188 | V(illegal_return_symbol, "illegal_return") \ |
| 189 | V(illegal_break_symbol, "illegal_break") \ |
| 190 | V(illegal_continue_symbol, "illegal_continue") \ |
| 191 | V(unknown_label_symbol, "unknown_label") \ |
| 192 | V(redeclaration_symbol, "redeclaration") \ |
| 193 | V(failure_symbol, "<failure>") \ |
| 194 | V(space_symbol, " ") \ |
| 195 | V(exec_symbol, "exec") \ |
| 196 | V(zero_symbol, "0") \ |
| 197 | V(global_eval_symbol, "GlobalEval") \ |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 198 | V(identity_hash_symbol, "v8::IdentityHash") \ |
| 199 | V(closure_symbol, "(closure)") |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 200 | |
| 201 | |
| 202 | // Forward declaration of the GCTracer class. |
| 203 | class GCTracer; |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 204 | class HeapStats; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 205 | |
| 206 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 207 | typedef String* (*ExternalStringTableUpdaterCallback)(Object** pointer); |
| 208 | |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 209 | typedef bool (*DirtyRegionCallback)(Address start, |
| 210 | Address end, |
| 211 | ObjectSlotCallback copy_object_func); |
| 212 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 213 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 214 | // The all static Heap captures the interface to the global object heap. |
| 215 | // All JavaScript contexts by this process share the same object heap. |
| 216 | |
| 217 | class Heap : public AllStatic { |
| 218 | public: |
| 219 | // Configure heap size before setup. Return false if the heap has been |
| 220 | // setup already. |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 221 | static bool ConfigureHeap(int max_semispace_size, int max_old_gen_size); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 222 | static bool ConfigureHeapDefault(); |
| 223 | |
| 224 | // Initializes the global object heap. If create_heap_objects is true, |
| 225 | // also creates the basic non-mutable objects. |
| 226 | // Returns whether it succeeded. |
| 227 | static bool Setup(bool create_heap_objects); |
| 228 | |
| 229 | // Destroys all memory allocated by the heap. |
| 230 | static void TearDown(); |
| 231 | |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 232 | // Set the stack limit in the roots_ array. Some architectures generate |
| 233 | // code that looks here, because it is faster than loading from the static |
| 234 | // jslimit_/real_jslimit_ variable in the StackGuard. |
| 235 | static void SetStackLimits(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 236 | |
| 237 | // Returns whether Setup has been called. |
| 238 | static bool HasBeenSetup(); |
| 239 | |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 240 | // Returns the maximum amount of memory reserved for the heap. For |
| 241 | // the young generation, we reserve 4 times the amount needed for a |
| 242 | // semi space. The young generation consists of two semi spaces and |
| 243 | // we reserve twice the amount needed for those in order to ensure |
| 244 | // that new space can be aligned to its size. |
| 245 | static int MaxReserved() { |
| 246 | return 4 * reserved_semispace_size_ + max_old_generation_size_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 247 | } |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 248 | static int MaxSemiSpaceSize() { return max_semispace_size_; } |
| 249 | static int ReservedSemiSpaceSize() { return reserved_semispace_size_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 250 | static int InitialSemiSpaceSize() { return initial_semispace_size_; } |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 251 | static int MaxOldGenerationSize() { return max_old_generation_size_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 252 | |
| 253 | // Returns the capacity of the heap in bytes w/o growing. Heap grows when |
| 254 | // more spaces are needed until it reaches the limit. |
| 255 | static int Capacity(); |
| 256 | |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 257 | // Returns the amount of memory currently committed for the heap. |
| 258 | static int CommittedMemory(); |
| 259 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 260 | // Returns the available bytes in space w/o growing. |
| 261 | // Heap doesn't guarantee that it can allocate an object that requires |
| 262 | // all available bytes. Check MaxHeapObjectSize() instead. |
| 263 | static int Available(); |
| 264 | |
| 265 | // Returns the maximum object size in paged space. |
| 266 | static inline int MaxObjectSizeInPagedSpace(); |
| 267 | |
| 268 | // Returns of size of all objects residing in the heap. |
| 269 | static int SizeOfObjects(); |
| 270 | |
| 271 | // Return the starting address and a mask for the new space. And-masking an |
| 272 | // address with the mask will result in the start address of the new space |
| 273 | // for all addresses in either semispace. |
| 274 | static Address NewSpaceStart() { return new_space_.start(); } |
| 275 | static uintptr_t NewSpaceMask() { return new_space_.mask(); } |
| 276 | static Address NewSpaceTop() { return new_space_.top(); } |
| 277 | |
| 278 | static NewSpace* new_space() { return &new_space_; } |
| 279 | static OldSpace* old_pointer_space() { return old_pointer_space_; } |
| 280 | static OldSpace* old_data_space() { return old_data_space_; } |
| 281 | static OldSpace* code_space() { return code_space_; } |
| 282 | static MapSpace* map_space() { return map_space_; } |
| 283 | static CellSpace* cell_space() { return cell_space_; } |
| 284 | static LargeObjectSpace* lo_space() { return lo_space_; } |
| 285 | |
| 286 | static bool always_allocate() { return always_allocate_scope_depth_ != 0; } |
| 287 | static Address always_allocate_scope_depth_address() { |
| 288 | return reinterpret_cast<Address>(&always_allocate_scope_depth_); |
| 289 | } |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 290 | static bool linear_allocation() { |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 291 | return linear_allocation_scope_depth_ != 0; |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 292 | } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 293 | |
| 294 | static Address* NewSpaceAllocationTopAddress() { |
| 295 | return new_space_.allocation_top_address(); |
| 296 | } |
| 297 | static Address* NewSpaceAllocationLimitAddress() { |
| 298 | return new_space_.allocation_limit_address(); |
| 299 | } |
| 300 | |
| 301 | // Uncommit unused semi space. |
| 302 | static bool UncommitFromSpace() { return new_space_.UncommitFromSpace(); } |
| 303 | |
| 304 | #ifdef ENABLE_HEAP_PROTECTION |
| 305 | // Protect/unprotect the heap by marking all spaces read-only/writable. |
| 306 | static void Protect(); |
| 307 | static void Unprotect(); |
| 308 | #endif |
| 309 | |
| 310 | // Allocates and initializes a new JavaScript object based on a |
| 311 | // constructor. |
| 312 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 313 | // failed. |
| 314 | // Please note this does not perform a garbage collection. |
| 315 | static Object* AllocateJSObject(JSFunction* constructor, |
| 316 | PretenureFlag pretenure = NOT_TENURED); |
| 317 | |
| 318 | // Allocates and initializes a new global object based on a constructor. |
| 319 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 320 | // failed. |
| 321 | // Please note this does not perform a garbage collection. |
| 322 | static Object* AllocateGlobalObject(JSFunction* constructor); |
| 323 | |
| 324 | // Returns a deep copy of the JavaScript object. |
| 325 | // Properties and elements are copied too. |
| 326 | // Returns failure if allocation failed. |
| 327 | static Object* CopyJSObject(JSObject* source); |
| 328 | |
| 329 | // Allocates the function prototype. |
| 330 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 331 | // failed. |
| 332 | // Please note this does not perform a garbage collection. |
| 333 | static Object* AllocateFunctionPrototype(JSFunction* function); |
| 334 | |
| 335 | // Reinitialize an JSGlobalProxy based on a constructor. The object |
| 336 | // must have the same size as objects allocated using the |
| 337 | // constructor. The object is reinitialized and behaves as an |
| 338 | // object that has been freshly allocated using the constructor. |
| 339 | static Object* ReinitializeJSGlobalProxy(JSFunction* constructor, |
| 340 | JSGlobalProxy* global); |
| 341 | |
| 342 | // Allocates and initializes a new JavaScript object based on a map. |
| 343 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 344 | // failed. |
| 345 | // Please note this does not perform a garbage collection. |
| 346 | static Object* AllocateJSObjectFromMap(Map* map, |
| 347 | PretenureFlag pretenure = NOT_TENURED); |
| 348 | |
| 349 | // Allocates a heap object based on the map. |
| 350 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 351 | // failed. |
| 352 | // Please note this function does not perform a garbage collection. |
| 353 | static Object* Allocate(Map* map, AllocationSpace space); |
| 354 | |
| 355 | // Allocates a JS Map in the heap. |
| 356 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 357 | // failed. |
| 358 | // Please note this function does not perform a garbage collection. |
| 359 | static Object* AllocateMap(InstanceType instance_type, int instance_size); |
| 360 | |
| 361 | // Allocates a partial map for bootstrapping. |
| 362 | static Object* AllocatePartialMap(InstanceType instance_type, |
| 363 | int instance_size); |
| 364 | |
| 365 | // Allocate a map for the specified function |
| 366 | static Object* AllocateInitialMap(JSFunction* fun); |
| 367 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 368 | // Allocates an empty code cache. |
| 369 | static Object* AllocateCodeCache(); |
| 370 | |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 371 | // Clear the Instanceof cache (used when a prototype changes). |
| 372 | static void ClearInstanceofCache() { |
| 373 | set_instanceof_cache_function(the_hole_value()); |
| 374 | } |
| 375 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 376 | // Allocates and fully initializes a String. There are two String |
| 377 | // encodings: ASCII and two byte. One should choose between the three string |
| 378 | // allocation functions based on the encoding of the string buffer used to |
| 379 | // initialized the string. |
| 380 | // - ...FromAscii initializes the string from a buffer that is ASCII |
| 381 | // encoded (it does not check that the buffer is ASCII encoded) and the |
| 382 | // result will be ASCII encoded. |
| 383 | // - ...FromUTF8 initializes the string from a buffer that is UTF-8 |
| 384 | // encoded. If the characters are all single-byte characters, the |
| 385 | // result will be ASCII encoded, otherwise it will converted to two |
| 386 | // byte. |
| 387 | // - ...FromTwoByte initializes the string from a buffer that is two-byte |
| 388 | // encoded. If the characters are all single-byte characters, the |
| 389 | // result will be converted to ASCII, otherwise it will be left as |
| 390 | // two-byte. |
| 391 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 392 | // failed. |
| 393 | // Please note this does not perform a garbage collection. |
| 394 | static Object* AllocateStringFromAscii( |
| 395 | Vector<const char> str, |
| 396 | PretenureFlag pretenure = NOT_TENURED); |
| 397 | static Object* AllocateStringFromUtf8( |
| 398 | Vector<const char> str, |
| 399 | PretenureFlag pretenure = NOT_TENURED); |
| 400 | static Object* AllocateStringFromTwoByte( |
| 401 | Vector<const uc16> str, |
| 402 | PretenureFlag pretenure = NOT_TENURED); |
| 403 | |
| 404 | // Allocates a symbol in old space based on the character stream. |
| 405 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 406 | // failed. |
| 407 | // Please note this function does not perform a garbage collection. |
| 408 | static inline Object* AllocateSymbol(Vector<const char> str, |
| 409 | int chars, |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 410 | uint32_t hash_field); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 411 | |
| 412 | static Object* AllocateInternalSymbol(unibrow::CharacterStream* buffer, |
| 413 | int chars, |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 414 | uint32_t hash_field); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 415 | |
| 416 | static Object* AllocateExternalSymbol(Vector<const char> str, |
| 417 | int chars); |
| 418 | |
| 419 | |
| 420 | // Allocates and partially initializes a String. There are two String |
| 421 | // encodings: ASCII and two byte. These functions allocate a string of the |
| 422 | // given length and set its map and length fields. The characters of the |
| 423 | // string are uninitialized. |
| 424 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 425 | // failed. |
| 426 | // Please note this does not perform a garbage collection. |
| 427 | static Object* AllocateRawAsciiString( |
| 428 | int length, |
| 429 | PretenureFlag pretenure = NOT_TENURED); |
| 430 | static Object* AllocateRawTwoByteString( |
| 431 | int length, |
| 432 | PretenureFlag pretenure = NOT_TENURED); |
| 433 | |
| 434 | // Computes a single character string where the character has code. |
| 435 | // A cache is used for ascii codes. |
| 436 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 437 | // failed. Please note this does not perform a garbage collection. |
| 438 | static Object* LookupSingleCharacterStringFromCode(uint16_t code); |
| 439 | |
| 440 | // Allocate a byte array of the specified length |
| 441 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 442 | // failed. |
| 443 | // Please note this does not perform a garbage collection. |
| 444 | static Object* AllocateByteArray(int length, PretenureFlag pretenure); |
| 445 | |
| 446 | // Allocate a non-tenured byte array of the specified length |
| 447 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 448 | // failed. |
| 449 | // Please note this does not perform a garbage collection. |
| 450 | static Object* AllocateByteArray(int length); |
| 451 | |
| 452 | // Allocate a pixel array of the specified length |
| 453 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 454 | // failed. |
| 455 | // Please note this does not perform a garbage collection. |
| 456 | static Object* AllocatePixelArray(int length, |
| 457 | uint8_t* external_pointer, |
| 458 | PretenureFlag pretenure); |
| 459 | |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 460 | // Allocates an external array of the specified length and type. |
| 461 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 462 | // failed. |
| 463 | // Please note this does not perform a garbage collection. |
| 464 | static Object* AllocateExternalArray(int length, |
| 465 | ExternalArrayType array_type, |
| 466 | void* external_pointer, |
| 467 | PretenureFlag pretenure); |
| 468 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 469 | // Allocate a tenured JS global property cell. |
| 470 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 471 | // failed. |
| 472 | // Please note this does not perform a garbage collection. |
| 473 | static Object* AllocateJSGlobalPropertyCell(Object* value); |
| 474 | |
| 475 | // Allocates a fixed array initialized with undefined values |
| 476 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 477 | // failed. |
| 478 | // Please note this does not perform a garbage collection. |
| 479 | static Object* AllocateFixedArray(int length, PretenureFlag pretenure); |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 480 | // Allocates a fixed array initialized with undefined values |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 481 | static Object* AllocateFixedArray(int length); |
| 482 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 483 | // Allocates an uninitialized fixed array. It must be filled by the caller. |
| 484 | // |
| 485 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 486 | // failed. |
| 487 | // Please note this does not perform a garbage collection. |
| 488 | static Object* AllocateUninitializedFixedArray(int length); |
| 489 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 490 | // Make a copy of src and return it. Returns |
| 491 | // Failure::RetryAfterGC(requested_bytes, space) if the allocation failed. |
| 492 | static Object* CopyFixedArray(FixedArray* src); |
| 493 | |
| 494 | // Allocates a fixed array initialized with the hole values. |
| 495 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 496 | // failed. |
| 497 | // Please note this does not perform a garbage collection. |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 498 | static Object* AllocateFixedArrayWithHoles( |
| 499 | int length, |
| 500 | PretenureFlag pretenure = NOT_TENURED); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 501 | |
| 502 | // AllocateHashTable is identical to AllocateFixedArray except |
| 503 | // that the resulting object has hash_table_map as map. |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 504 | static Object* AllocateHashTable(int length, |
| 505 | PretenureFlag pretenure = NOT_TENURED); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 506 | |
| 507 | // Allocate a global (but otherwise uninitialized) context. |
| 508 | static Object* AllocateGlobalContext(); |
| 509 | |
| 510 | // Allocate a function context. |
| 511 | static Object* AllocateFunctionContext(int length, JSFunction* closure); |
| 512 | |
| 513 | // Allocate a 'with' context. |
| 514 | static Object* AllocateWithContext(Context* previous, |
| 515 | JSObject* extension, |
| 516 | bool is_catch_context); |
| 517 | |
| 518 | // Allocates a new utility object in the old generation. |
| 519 | static Object* AllocateStruct(InstanceType type); |
| 520 | |
| 521 | // Allocates a function initialized with a shared part. |
| 522 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 523 | // failed. |
| 524 | // Please note this does not perform a garbage collection. |
| 525 | static Object* AllocateFunction(Map* function_map, |
| 526 | SharedFunctionInfo* shared, |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 527 | Object* prototype, |
| 528 | PretenureFlag pretenure = TENURED); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 529 | |
| 530 | // Indicies for direct access into argument objects. |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 531 | static const int kArgumentsObjectSize = |
| 532 | JSObject::kHeaderSize + 2 * kPointerSize; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 533 | static const int arguments_callee_index = 0; |
| 534 | static const int arguments_length_index = 1; |
| 535 | |
| 536 | // Allocates an arguments object - optionally with an elements array. |
| 537 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 538 | // failed. |
| 539 | // Please note this does not perform a garbage collection. |
| 540 | static Object* AllocateArgumentsObject(Object* callee, int length); |
| 541 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 542 | // Same as NewNumberFromDouble, but may return a preallocated/immutable |
| 543 | // number object (e.g., minus_zero_value_, nan_value_) |
| 544 | static Object* NumberFromDouble(double value, |
| 545 | PretenureFlag pretenure = NOT_TENURED); |
| 546 | |
| 547 | // Allocated a HeapNumber from value. |
| 548 | static Object* AllocateHeapNumber(double value, PretenureFlag pretenure); |
| 549 | static Object* AllocateHeapNumber(double value); // pretenure = NOT_TENURED |
| 550 | |
| 551 | // Converts an int into either a Smi or a HeapNumber object. |
| 552 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 553 | // failed. |
| 554 | // Please note this does not perform a garbage collection. |
| 555 | static inline Object* NumberFromInt32(int32_t value); |
| 556 | |
| 557 | // Converts an int into either a Smi or a HeapNumber object. |
| 558 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 559 | // failed. |
| 560 | // Please note this does not perform a garbage collection. |
| 561 | static inline Object* NumberFromUint32(uint32_t value); |
| 562 | |
| 563 | // Allocates a new proxy object. |
| 564 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 565 | // failed. |
| 566 | // Please note this does not perform a garbage collection. |
| 567 | static Object* AllocateProxy(Address proxy, |
| 568 | PretenureFlag pretenure = NOT_TENURED); |
| 569 | |
| 570 | // Allocates a new SharedFunctionInfo object. |
| 571 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 572 | // failed. |
| 573 | // Please note this does not perform a garbage collection. |
| 574 | static Object* AllocateSharedFunctionInfo(Object* name); |
| 575 | |
| 576 | // Allocates a new cons string object. |
| 577 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 578 | // failed. |
| 579 | // Please note this does not perform a garbage collection. |
| 580 | static Object* AllocateConsString(String* first, String* second); |
| 581 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 582 | // Allocates a new sub string object which is a substring of an underlying |
| 583 | // string buffer stretching from the index start (inclusive) to the index |
| 584 | // end (exclusive). |
| 585 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 586 | // failed. |
| 587 | // Please note this does not perform a garbage collection. |
| 588 | static Object* AllocateSubString(String* buffer, |
| 589 | int start, |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 590 | int end, |
| 591 | PretenureFlag pretenure = NOT_TENURED); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 592 | |
| 593 | // Allocate a new external string object, which is backed by a string |
| 594 | // resource that resides outside the V8 heap. |
| 595 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 596 | // failed. |
| 597 | // Please note this does not perform a garbage collection. |
| 598 | static Object* AllocateExternalStringFromAscii( |
| 599 | ExternalAsciiString::Resource* resource); |
| 600 | static Object* AllocateExternalStringFromTwoByte( |
| 601 | ExternalTwoByteString::Resource* resource); |
| 602 | |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 603 | // Finalizes an external string by deleting the associated external |
| 604 | // data and clearing the resource pointer. |
| 605 | static inline void FinalizeExternalString(String* string); |
| 606 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 607 | // Allocates an uninitialized object. The memory is non-executable if the |
| 608 | // hardware and OS allow. |
| 609 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 610 | // failed. |
| 611 | // Please note this function does not perform a garbage collection. |
| 612 | static inline Object* AllocateRaw(int size_in_bytes, |
| 613 | AllocationSpace space, |
| 614 | AllocationSpace retry_space); |
| 615 | |
| 616 | // Initialize a filler object to keep the ability to iterate over the heap |
| 617 | // when shortening objects. |
| 618 | static void CreateFillerObjectAt(Address addr, int size); |
| 619 | |
| 620 | // Makes a new native code object |
| 621 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 622 | // failed. On success, the pointer to the Code object is stored in the |
| 623 | // self_reference. This allows generated code to reference its own Code |
| 624 | // object by containing this pointer. |
| 625 | // Please note this function does not perform a garbage collection. |
| 626 | static Object* CreateCode(const CodeDesc& desc, |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 627 | Code::Flags flags, |
| 628 | Handle<Object> self_reference); |
| 629 | |
| 630 | static Object* CopyCode(Code* code); |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 631 | |
| 632 | // Copy the code and scope info part of the code object, but insert |
| 633 | // the provided data as the relocation information. |
| 634 | static Object* CopyCode(Code* code, Vector<byte> reloc_info); |
| 635 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 636 | // Finds the symbol for string in the symbol table. |
| 637 | // If not found, a new symbol is added to the table and returned. |
| 638 | // Returns Failure::RetryAfterGC(requested_bytes, space) if allocation |
| 639 | // failed. |
| 640 | // Please note this function does not perform a garbage collection. |
| 641 | static Object* LookupSymbol(Vector<const char> str); |
| 642 | static Object* LookupAsciiSymbol(const char* str) { |
| 643 | return LookupSymbol(CStrVector(str)); |
| 644 | } |
| 645 | static Object* LookupSymbol(String* str); |
| 646 | static bool LookupSymbolIfExists(String* str, String** symbol); |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 647 | static bool LookupTwoCharsSymbolIfExists(String* str, String** symbol); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 648 | |
| 649 | // Compute the matching symbol map for a string if possible. |
| 650 | // NULL is returned if string is in new space or not flattened. |
| 651 | static Map* SymbolMapForString(String* str); |
| 652 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 653 | // Tries to flatten a string before compare operation. |
| 654 | // |
| 655 | // Returns a failure in case it was decided that flattening was |
| 656 | // necessary and failed. Note, if flattening is not necessary the |
| 657 | // string might stay non-flat even when not a failure is returned. |
| 658 | // |
| 659 | // Please note this function does not perform a garbage collection. |
| 660 | static inline Object* PrepareForCompare(String* str); |
| 661 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 662 | // Converts the given boolean condition to JavaScript boolean value. |
| 663 | static Object* ToBoolean(bool condition) { |
| 664 | return condition ? true_value() : false_value(); |
| 665 | } |
| 666 | |
| 667 | // Code that should be run before and after each GC. Includes some |
| 668 | // reporting/verification activities when compiled with DEBUG set. |
| 669 | static void GarbageCollectionPrologue(); |
| 670 | static void GarbageCollectionEpilogue(); |
| 671 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 672 | // Performs garbage collection operation. |
| 673 | // Returns whether required_space bytes are available after the collection. |
| 674 | static bool CollectGarbage(int required_space, AllocationSpace space); |
| 675 | |
| 676 | // Performs a full garbage collection. Force compaction if the |
| 677 | // parameter is true. |
| 678 | static void CollectAllGarbage(bool force_compaction); |
| 679 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 680 | // Notify the heap that a context has been disposed. |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 681 | static int NotifyContextDisposed() { return ++contexts_disposed_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 682 | |
| 683 | // Utility to invoke the scavenger. This is needed in test code to |
| 684 | // ensure correct callback for weak global handles. |
| 685 | static void PerformScavenge(); |
| 686 | |
| 687 | #ifdef DEBUG |
| 688 | // Utility used with flag gc-greedy. |
| 689 | static bool GarbageCollectionGreedyCheck(); |
| 690 | #endif |
| 691 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 692 | static void AddGCPrologueCallback( |
| 693 | GCEpilogueCallback callback, GCType gc_type_filter); |
| 694 | static void RemoveGCPrologueCallback(GCEpilogueCallback callback); |
| 695 | |
| 696 | static void AddGCEpilogueCallback( |
| 697 | GCEpilogueCallback callback, GCType gc_type_filter); |
| 698 | static void RemoveGCEpilogueCallback(GCEpilogueCallback callback); |
| 699 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 700 | static void SetGlobalGCPrologueCallback(GCCallback callback) { |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 701 | ASSERT((callback == NULL) ^ (global_gc_prologue_callback_ == NULL)); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 702 | global_gc_prologue_callback_ = callback; |
| 703 | } |
| 704 | static void SetGlobalGCEpilogueCallback(GCCallback callback) { |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 705 | ASSERT((callback == NULL) ^ (global_gc_epilogue_callback_ == NULL)); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 706 | global_gc_epilogue_callback_ = callback; |
| 707 | } |
| 708 | |
| 709 | // Heap root getters. We have versions with and without type::cast() here. |
| 710 | // You can't use type::cast during GC because the assert fails. |
| 711 | #define ROOT_ACCESSOR(type, name, camel_name) \ |
| 712 | static inline type* name() { \ |
| 713 | return type::cast(roots_[k##camel_name##RootIndex]); \ |
| 714 | } \ |
| 715 | static inline type* raw_unchecked_##name() { \ |
| 716 | return reinterpret_cast<type*>(roots_[k##camel_name##RootIndex]); \ |
| 717 | } |
| 718 | ROOT_LIST(ROOT_ACCESSOR) |
| 719 | #undef ROOT_ACCESSOR |
| 720 | |
| 721 | // Utility type maps |
| 722 | #define STRUCT_MAP_ACCESSOR(NAME, Name, name) \ |
| 723 | static inline Map* name##_map() { \ |
| 724 | return Map::cast(roots_[k##Name##MapRootIndex]); \ |
| 725 | } |
| 726 | STRUCT_LIST(STRUCT_MAP_ACCESSOR) |
| 727 | #undef STRUCT_MAP_ACCESSOR |
| 728 | |
| 729 | #define SYMBOL_ACCESSOR(name, str) static inline String* name() { \ |
| 730 | return String::cast(roots_[k##name##RootIndex]); \ |
| 731 | } |
| 732 | SYMBOL_LIST(SYMBOL_ACCESSOR) |
| 733 | #undef SYMBOL_ACCESSOR |
| 734 | |
| 735 | // The hidden_symbol is special because it is the empty string, but does |
| 736 | // not match the empty string. |
| 737 | static String* hidden_symbol() { return hidden_symbol_; } |
| 738 | |
| 739 | // Iterates over all roots in the heap. |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 740 | static void IterateRoots(ObjectVisitor* v, VisitMode mode); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 741 | // Iterates over all strong roots in the heap. |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 742 | static void IterateStrongRoots(ObjectVisitor* v, VisitMode mode); |
Leon Clarke | d91b9f7 | 2010-01-27 17:25:45 +0000 | [diff] [blame] | 743 | // Iterates over all the other roots in the heap. |
| 744 | static void IterateWeakRoots(ObjectVisitor* v, VisitMode mode); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 745 | |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 746 | enum ExpectedPageWatermarkState { |
| 747 | WATERMARK_SHOULD_BE_VALID, |
| 748 | WATERMARK_CAN_BE_INVALID |
| 749 | }; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 750 | |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 751 | // For each dirty region on a page in use from an old space call |
| 752 | // visit_dirty_region callback. |
| 753 | // If either visit_dirty_region or callback can cause an allocation |
| 754 | // in old space and changes in allocation watermark then |
| 755 | // can_preallocate_during_iteration should be set to true. |
| 756 | // All pages will be marked as having invalid watermark upon |
| 757 | // iteration completion. |
| 758 | static void IterateDirtyRegions( |
| 759 | PagedSpace* space, |
| 760 | DirtyRegionCallback visit_dirty_region, |
| 761 | ObjectSlotCallback callback, |
| 762 | ExpectedPageWatermarkState expected_page_watermark_state); |
| 763 | |
| 764 | // Interpret marks as a bitvector of dirty marks for regions of size |
| 765 | // Page::kRegionSize aligned by Page::kRegionAlignmentMask and covering |
| 766 | // memory interval from start to top. For each dirty region call a |
| 767 | // visit_dirty_region callback. Return updated bitvector of dirty marks. |
| 768 | static uint32_t IterateDirtyRegions(uint32_t marks, |
| 769 | Address start, |
| 770 | Address end, |
| 771 | DirtyRegionCallback visit_dirty_region, |
| 772 | ObjectSlotCallback callback); |
| 773 | |
Ben Murdoch | 3bec4d2 | 2010-07-22 14:51:16 +0100 | [diff] [blame^] | 774 | // Iterate pointers to from semispace of new space found in memory interval |
| 775 | // from start to end. |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 776 | // Update dirty marks for page containing start address. |
Ben Murdoch | 3bec4d2 | 2010-07-22 14:51:16 +0100 | [diff] [blame^] | 777 | static void IterateAndMarkPointersToFromSpace(Address start, |
| 778 | Address end, |
| 779 | ObjectSlotCallback callback); |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 780 | |
| 781 | // Iterate pointers to new space found in memory interval from start to end. |
| 782 | // Return true if pointers to new space was found. |
| 783 | static bool IteratePointersInDirtyRegion(Address start, |
| 784 | Address end, |
| 785 | ObjectSlotCallback callback); |
| 786 | |
| 787 | |
| 788 | // Iterate pointers to new space found in memory interval from start to end. |
| 789 | // This interval is considered to belong to the map space. |
| 790 | // Return true if pointers to new space was found. |
| 791 | static bool IteratePointersInDirtyMapsRegion(Address start, |
| 792 | Address end, |
| 793 | ObjectSlotCallback callback); |
| 794 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 795 | |
| 796 | // Returns whether the object resides in new space. |
| 797 | static inline bool InNewSpace(Object* object); |
| 798 | static inline bool InFromSpace(Object* object); |
| 799 | static inline bool InToSpace(Object* object); |
| 800 | |
| 801 | // Checks whether an address/object in the heap (including auxiliary |
| 802 | // area and unused area). |
| 803 | static bool Contains(Address addr); |
| 804 | static bool Contains(HeapObject* value); |
| 805 | |
| 806 | // Checks whether an address/object in a space. |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 807 | // Currently used by tests, serialization and heap verification only. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 808 | static bool InSpace(Address addr, AllocationSpace space); |
| 809 | static bool InSpace(HeapObject* value, AllocationSpace space); |
| 810 | |
| 811 | // Finds out which space an object should get promoted to based on its type. |
| 812 | static inline OldSpace* TargetSpace(HeapObject* object); |
| 813 | static inline AllocationSpace TargetSpaceId(InstanceType type); |
| 814 | |
| 815 | // Sets the stub_cache_ (only used when expanding the dictionary). |
| 816 | static void public_set_code_stubs(NumberDictionary* value) { |
| 817 | roots_[kCodeStubsRootIndex] = value; |
| 818 | } |
| 819 | |
| 820 | // Sets the non_monomorphic_cache_ (only used when expanding the dictionary). |
| 821 | static void public_set_non_monomorphic_cache(NumberDictionary* value) { |
| 822 | roots_[kNonMonomorphicCacheRootIndex] = value; |
| 823 | } |
| 824 | |
Andrei Popescu | 3100271 | 2010-02-23 13:46:05 +0000 | [diff] [blame] | 825 | static void public_set_empty_script(Script* script) { |
| 826 | roots_[kEmptyScriptRootIndex] = script; |
| 827 | } |
| 828 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 829 | // Update the next script id. |
| 830 | static inline void SetLastScriptId(Object* last_script_id); |
| 831 | |
| 832 | // Generated code can embed this address to get access to the roots. |
| 833 | static Object** roots_address() { return roots_; } |
| 834 | |
| 835 | #ifdef DEBUG |
| 836 | static void Print(); |
| 837 | static void PrintHandles(); |
| 838 | |
| 839 | // Verify the heap is in its normal state before or after a GC. |
| 840 | static void Verify(); |
| 841 | |
| 842 | // Report heap statistics. |
| 843 | static void ReportHeapStatistics(const char* title); |
| 844 | static void ReportCodeStatistics(const char* title); |
| 845 | |
| 846 | // Fill in bogus values in from space |
| 847 | static void ZapFromSpace(); |
| 848 | #endif |
| 849 | |
| 850 | #if defined(ENABLE_LOGGING_AND_PROFILING) |
| 851 | // Print short heap statistics. |
| 852 | static void PrintShortHeapStatistics(); |
| 853 | #endif |
| 854 | |
| 855 | // Makes a new symbol object |
| 856 | // Returns Failure::RetryAfterGC(requested_bytes, space) if the allocation |
| 857 | // failed. |
| 858 | // Please note this function does not perform a garbage collection. |
| 859 | static Object* CreateSymbol(const char* str, int length, int hash); |
| 860 | static Object* CreateSymbol(String* str); |
| 861 | |
| 862 | // Write barrier support for address[offset] = o. |
| 863 | static inline void RecordWrite(Address address, int offset); |
| 864 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 865 | // Write barrier support for address[start : start + len[ = o. |
| 866 | static inline void RecordWrites(Address address, int start, int len); |
| 867 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 868 | // Given an address occupied by a live code object, return that object. |
| 869 | static Object* FindCodeObject(Address a); |
| 870 | |
| 871 | // Invoke Shrink on shrinkable spaces. |
| 872 | static void Shrink(); |
| 873 | |
| 874 | enum HeapState { NOT_IN_GC, SCAVENGE, MARK_COMPACT }; |
| 875 | static inline HeapState gc_state() { return gc_state_; } |
| 876 | |
| 877 | #ifdef DEBUG |
| 878 | static bool IsAllocationAllowed() { return allocation_allowed_; } |
| 879 | static inline bool allow_allocation(bool enable); |
| 880 | |
| 881 | static bool disallow_allocation_failure() { |
| 882 | return disallow_allocation_failure_; |
| 883 | } |
| 884 | |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 885 | static void TracePathToObject(Object* target); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 886 | static void TracePathToGlobal(); |
| 887 | #endif |
| 888 | |
| 889 | // Callback function passed to Heap::Iterate etc. Copies an object if |
| 890 | // necessary, the object might be promoted to an old space. The caller must |
| 891 | // ensure the precondition that the object is (a) a heap object and (b) in |
| 892 | // the heap's from space. |
| 893 | static void ScavengePointer(HeapObject** p); |
| 894 | static inline void ScavengeObject(HeapObject** p, HeapObject* object); |
| 895 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 896 | // Commits from space if it is uncommitted. |
| 897 | static void EnsureFromSpaceIsCommitted(); |
| 898 | |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 899 | // Support for partial snapshots. After calling this we can allocate a |
| 900 | // certain number of bytes using only linear allocation (with a |
| 901 | // LinearAllocationScope and an AlwaysAllocateScope) without using freelists |
| 902 | // or causing a GC. It returns true of space was reserved or false if a GC is |
| 903 | // needed. For paged spaces the space requested must include the space wasted |
| 904 | // at the end of each page when allocating linearly. |
| 905 | static void ReserveSpace( |
| 906 | int new_space_size, |
| 907 | int pointer_space_size, |
| 908 | int data_space_size, |
| 909 | int code_space_size, |
| 910 | int map_space_size, |
| 911 | int cell_space_size, |
| 912 | int large_object_size); |
| 913 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 914 | // |
| 915 | // Support for the API. |
| 916 | // |
| 917 | |
| 918 | static bool CreateApiObjects(); |
| 919 | |
| 920 | // Attempt to find the number in a small cache. If we finds it, return |
| 921 | // the string representation of the number. Otherwise return undefined. |
| 922 | static Object* GetNumberStringCache(Object* number); |
| 923 | |
| 924 | // Update the cache with a new number-string pair. |
| 925 | static void SetNumberStringCache(Object* number, String* str); |
| 926 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 927 | // Adjusts the amount of registered external memory. |
| 928 | // Returns the adjusted value. |
| 929 | static inline int AdjustAmountOfExternalAllocatedMemory(int change_in_bytes); |
| 930 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 931 | // Allocate uninitialized fixed array. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 932 | static Object* AllocateRawFixedArray(int length); |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 933 | static Object* AllocateRawFixedArray(int length, |
| 934 | PretenureFlag pretenure); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 935 | |
| 936 | // True if we have reached the allocation limit in the old generation that |
| 937 | // should force the next GC (caused normally) to be a full one. |
| 938 | static bool OldGenerationPromotionLimitReached() { |
| 939 | return (PromotedSpaceSize() + PromotedExternalMemorySize()) |
| 940 | > old_gen_promotion_limit_; |
| 941 | } |
| 942 | |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 943 | static intptr_t OldGenerationSpaceAvailable() { |
| 944 | return old_gen_allocation_limit_ - |
| 945 | (PromotedSpaceSize() + PromotedExternalMemorySize()); |
| 946 | } |
| 947 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 948 | // True if we have reached the allocation limit in the old generation that |
| 949 | // should artificially cause a GC right now. |
| 950 | static bool OldGenerationAllocationLimitReached() { |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 951 | return OldGenerationSpaceAvailable() < 0; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 952 | } |
| 953 | |
| 954 | // Can be called when the embedding application is idle. |
| 955 | static bool IdleNotification(); |
| 956 | |
| 957 | // Declare all the root indices. |
| 958 | enum RootListIndex { |
| 959 | #define ROOT_INDEX_DECLARATION(type, name, camel_name) k##camel_name##RootIndex, |
| 960 | STRONG_ROOT_LIST(ROOT_INDEX_DECLARATION) |
| 961 | #undef ROOT_INDEX_DECLARATION |
| 962 | |
| 963 | // Utility type maps |
| 964 | #define DECLARE_STRUCT_MAP(NAME, Name, name) k##Name##MapRootIndex, |
| 965 | STRUCT_LIST(DECLARE_STRUCT_MAP) |
| 966 | #undef DECLARE_STRUCT_MAP |
| 967 | |
| 968 | #define SYMBOL_INDEX_DECLARATION(name, str) k##name##RootIndex, |
| 969 | SYMBOL_LIST(SYMBOL_INDEX_DECLARATION) |
| 970 | #undef SYMBOL_DECLARATION |
| 971 | |
| 972 | kSymbolTableRootIndex, |
| 973 | kStrongRootListLength = kSymbolTableRootIndex, |
| 974 | kRootListLength |
| 975 | }; |
| 976 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 977 | static Object* NumberToString(Object* number, |
| 978 | bool check_number_string_cache = true); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 979 | |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 980 | static Map* MapForExternalArrayType(ExternalArrayType array_type); |
| 981 | static RootListIndex RootIndexForExternalArrayType( |
| 982 | ExternalArrayType array_type); |
| 983 | |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 984 | static void RecordStats(HeapStats* stats); |
| 985 | |
Ben Murdoch | 3bec4d2 | 2010-07-22 14:51:16 +0100 | [diff] [blame^] | 986 | static Scavenger GetScavenger(int instance_type, int instance_size); |
| 987 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 988 | // Copy block of memory from src to dst. Size of block should be aligned |
| 989 | // by pointer size. |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 990 | static inline void CopyBlock(Address dst, Address src, int byte_size); |
| 991 | |
| 992 | static inline void CopyBlockToOldSpaceAndUpdateRegionMarks(Address dst, |
| 993 | Address src, |
| 994 | int byte_size); |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 995 | |
| 996 | // Optimized version of memmove for blocks with pointer size aligned sizes and |
| 997 | // pointer size aligned addresses. |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 998 | static inline void MoveBlock(Address dst, Address src, int byte_size); |
| 999 | |
| 1000 | static inline void MoveBlockToOldSpaceAndUpdateRegionMarks(Address dst, |
| 1001 | Address src, |
| 1002 | int byte_size); |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1003 | |
| 1004 | // Check new space expansion criteria and expand semispaces if it was hit. |
| 1005 | static void CheckNewSpaceExpansionCriteria(); |
| 1006 | |
| 1007 | static inline void IncrementYoungSurvivorsCounter(int survived) { |
Steve Block | 8defd9f | 2010-07-08 12:39:36 +0100 | [diff] [blame] | 1008 | young_survivors_after_last_gc_ = survived; |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1009 | survived_since_last_expansion_ += survived; |
| 1010 | } |
| 1011 | |
| 1012 | static void UpdateNewSpaceReferencesInExternalStringTable( |
| 1013 | ExternalStringTableUpdaterCallback updater_func); |
| 1014 | |
| 1015 | // Helper function that governs the promotion policy from new space to |
| 1016 | // old. If the object's old address lies below the new space's age |
| 1017 | // mark or if we've already filled the bottom 1/16th of the to space, |
| 1018 | // we try to promote this object. |
| 1019 | static inline bool ShouldBePromoted(Address old_address, int object_size); |
| 1020 | |
| 1021 | static int MaxObjectSizeInNewSpace() { return kMaxObjectSizeInNewSpace; } |
| 1022 | |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 1023 | static void ClearJSFunctionResultCaches(); |
| 1024 | |
Leon Clarke | f7060e2 | 2010-06-03 12:02:55 +0100 | [diff] [blame] | 1025 | static GCTracer* tracer() { return tracer_; } |
| 1026 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1027 | private: |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 1028 | static int reserved_semispace_size_; |
| 1029 | static int max_semispace_size_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1030 | static int initial_semispace_size_; |
Steve Block | 3ce2e20 | 2009-11-05 08:53:23 +0000 | [diff] [blame] | 1031 | static int max_old_generation_size_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1032 | static size_t code_range_size_; |
| 1033 | |
| 1034 | // For keeping track of how much data has survived |
| 1035 | // scavenge since last new space expansion. |
| 1036 | static int survived_since_last_expansion_; |
| 1037 | |
| 1038 | static int always_allocate_scope_depth_; |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 1039 | static int linear_allocation_scope_depth_; |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1040 | |
| 1041 | // For keeping track of context disposals. |
| 1042 | static int contexts_disposed_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1043 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1044 | #if defined(V8_TARGET_ARCH_X64) |
| 1045 | static const int kMaxObjectSizeInNewSpace = 512*KB; |
| 1046 | #else |
| 1047 | static const int kMaxObjectSizeInNewSpace = 256*KB; |
| 1048 | #endif |
| 1049 | |
| 1050 | static NewSpace new_space_; |
| 1051 | static OldSpace* old_pointer_space_; |
| 1052 | static OldSpace* old_data_space_; |
| 1053 | static OldSpace* code_space_; |
| 1054 | static MapSpace* map_space_; |
| 1055 | static CellSpace* cell_space_; |
| 1056 | static LargeObjectSpace* lo_space_; |
| 1057 | static HeapState gc_state_; |
| 1058 | |
| 1059 | // Returns the size of object residing in non new spaces. |
| 1060 | static int PromotedSpaceSize(); |
| 1061 | |
| 1062 | // Returns the amount of external memory registered since last global gc. |
| 1063 | static int PromotedExternalMemorySize(); |
| 1064 | |
| 1065 | static int mc_count_; // how many mark-compact collections happened |
Leon Clarke | f7060e2 | 2010-06-03 12:02:55 +0100 | [diff] [blame] | 1066 | static int ms_count_; // how many mark-sweep collections happened |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1067 | static int gc_count_; // how many gc happened |
| 1068 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1069 | // Total length of the strings we failed to flatten since the last GC. |
| 1070 | static int unflattened_strings_length_; |
| 1071 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1072 | #define ROOT_ACCESSOR(type, name, camel_name) \ |
| 1073 | static inline void set_##name(type* value) { \ |
| 1074 | roots_[k##camel_name##RootIndex] = value; \ |
| 1075 | } |
| 1076 | ROOT_LIST(ROOT_ACCESSOR) |
| 1077 | #undef ROOT_ACCESSOR |
| 1078 | |
| 1079 | #ifdef DEBUG |
| 1080 | static bool allocation_allowed_; |
| 1081 | |
| 1082 | // If the --gc-interval flag is set to a positive value, this |
| 1083 | // variable holds the value indicating the number of allocations |
| 1084 | // remain until the next failure and garbage collection. |
| 1085 | static int allocation_timeout_; |
| 1086 | |
| 1087 | // Do we expect to be able to handle allocation failure at this |
| 1088 | // time? |
| 1089 | static bool disallow_allocation_failure_; |
| 1090 | #endif // DEBUG |
| 1091 | |
| 1092 | // Limit that triggers a global GC on the next (normally caused) GC. This |
| 1093 | // is checked when we have already decided to do a GC to help determine |
| 1094 | // which collector to invoke. |
| 1095 | static int old_gen_promotion_limit_; |
| 1096 | |
| 1097 | // Limit that triggers a global GC as soon as is reasonable. This is |
| 1098 | // checked before expanding a paged space in the old generation and on |
| 1099 | // every allocation in large object space. |
| 1100 | static int old_gen_allocation_limit_; |
| 1101 | |
| 1102 | // Limit on the amount of externally allocated memory allowed |
| 1103 | // between global GCs. If reached a global GC is forced. |
| 1104 | static int external_allocation_limit_; |
| 1105 | |
| 1106 | // The amount of external memory registered through the API kept alive |
| 1107 | // by global handles |
| 1108 | static int amount_of_external_allocated_memory_; |
| 1109 | |
| 1110 | // Caches the amount of external memory registered at the last global gc. |
| 1111 | static int amount_of_external_allocated_memory_at_last_global_gc_; |
| 1112 | |
| 1113 | // Indicates that an allocation has failed in the old generation since the |
| 1114 | // last GC. |
| 1115 | static int old_gen_exhausted_; |
| 1116 | |
| 1117 | static Object* roots_[kRootListLength]; |
| 1118 | |
| 1119 | struct StringTypeTable { |
| 1120 | InstanceType type; |
| 1121 | int size; |
| 1122 | RootListIndex index; |
| 1123 | }; |
| 1124 | |
| 1125 | struct ConstantSymbolTable { |
| 1126 | const char* contents; |
| 1127 | RootListIndex index; |
| 1128 | }; |
| 1129 | |
| 1130 | struct StructTable { |
| 1131 | InstanceType type; |
| 1132 | int size; |
| 1133 | RootListIndex index; |
| 1134 | }; |
| 1135 | |
| 1136 | static const StringTypeTable string_type_table[]; |
| 1137 | static const ConstantSymbolTable constant_symbol_table[]; |
| 1138 | static const StructTable struct_table[]; |
| 1139 | |
| 1140 | // The special hidden symbol which is an empty string, but does not match |
| 1141 | // any string when looked up in properties. |
| 1142 | static String* hidden_symbol_; |
| 1143 | |
| 1144 | // GC callback function, called before and after mark-compact GC. |
| 1145 | // Allocations in the callback function are disallowed. |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1146 | struct GCPrologueCallbackPair { |
| 1147 | GCPrologueCallbackPair(GCPrologueCallback callback, GCType gc_type) |
| 1148 | : callback(callback), gc_type(gc_type) { |
| 1149 | } |
| 1150 | bool operator==(const GCPrologueCallbackPair& pair) const { |
| 1151 | return pair.callback == callback; |
| 1152 | } |
| 1153 | GCPrologueCallback callback; |
| 1154 | GCType gc_type; |
| 1155 | }; |
| 1156 | static List<GCPrologueCallbackPair> gc_prologue_callbacks_; |
| 1157 | |
| 1158 | struct GCEpilogueCallbackPair { |
| 1159 | GCEpilogueCallbackPair(GCEpilogueCallback callback, GCType gc_type) |
| 1160 | : callback(callback), gc_type(gc_type) { |
| 1161 | } |
| 1162 | bool operator==(const GCEpilogueCallbackPair& pair) const { |
| 1163 | return pair.callback == callback; |
| 1164 | } |
| 1165 | GCEpilogueCallback callback; |
| 1166 | GCType gc_type; |
| 1167 | }; |
| 1168 | static List<GCEpilogueCallbackPair> gc_epilogue_callbacks_; |
| 1169 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1170 | static GCCallback global_gc_prologue_callback_; |
| 1171 | static GCCallback global_gc_epilogue_callback_; |
| 1172 | |
| 1173 | // Checks whether a global GC is necessary |
| 1174 | static GarbageCollector SelectGarbageCollector(AllocationSpace space); |
| 1175 | |
| 1176 | // Performs garbage collection |
| 1177 | static void PerformGarbageCollection(AllocationSpace space, |
| 1178 | GarbageCollector collector, |
| 1179 | GCTracer* tracer); |
| 1180 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1181 | // Allocate an uninitialized object in map space. The behavior is identical |
| 1182 | // to Heap::AllocateRaw(size_in_bytes, MAP_SPACE), except that (a) it doesn't |
| 1183 | // have to test the allocation space argument and (b) can reduce code size |
| 1184 | // (since both AllocateRaw and AllocateRawMap are inlined). |
| 1185 | static inline Object* AllocateRawMap(); |
| 1186 | |
| 1187 | // Allocate an uninitialized object in the global property cell space. |
| 1188 | static inline Object* AllocateRawCell(); |
| 1189 | |
| 1190 | // Initializes a JSObject based on its map. |
| 1191 | static void InitializeJSObjectFromMap(JSObject* obj, |
| 1192 | FixedArray* properties, |
| 1193 | Map* map); |
| 1194 | |
| 1195 | static bool CreateInitialMaps(); |
| 1196 | static bool CreateInitialObjects(); |
| 1197 | |
| 1198 | // These four Create*EntryStub functions are here because of a gcc-4.4 bug |
| 1199 | // that assigns wrong vtable entries. |
| 1200 | static void CreateCEntryStub(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1201 | static void CreateJSEntryStub(); |
| 1202 | static void CreateJSConstructEntryStub(); |
| 1203 | static void CreateRegExpCEntryStub(); |
| 1204 | |
| 1205 | static void CreateFixedStubs(); |
| 1206 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1207 | static Object* CreateOddball(const char* to_string, Object* to_number); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1208 | |
| 1209 | // Allocate empty fixed array. |
| 1210 | static Object* AllocateEmptyFixedArray(); |
| 1211 | |
| 1212 | // Performs a minor collection in new generation. |
| 1213 | static void Scavenge(); |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1214 | |
| 1215 | static String* UpdateNewSpaceReferenceInExternalStringTableEntry( |
| 1216 | Object** pointer); |
| 1217 | |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 1218 | static Address DoScavenge(ObjectVisitor* scavenge_visitor, |
| 1219 | Address new_space_front); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1220 | |
| 1221 | // Performs a major collection in the whole heap. |
| 1222 | static void MarkCompact(GCTracer* tracer); |
| 1223 | |
| 1224 | // Code to be run before and after mark-compact. |
| 1225 | static void MarkCompactPrologue(bool is_compacting); |
| 1226 | static void MarkCompactEpilogue(bool is_compacting); |
| 1227 | |
Kristian Monsen | 25f6136 | 2010-05-21 11:50:48 +0100 | [diff] [blame] | 1228 | // Completely clear the Instanceof cache (to stop it keeping objects alive |
| 1229 | // around a GC). |
| 1230 | static void CompletelyClearInstanceofCache() { |
| 1231 | set_instanceof_cache_map(the_hole_value()); |
| 1232 | set_instanceof_cache_function(the_hole_value()); |
| 1233 | } |
| 1234 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1235 | #if defined(DEBUG) || defined(ENABLE_LOGGING_AND_PROFILING) |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1236 | // Record statistics before and after garbage collection. |
| 1237 | static void ReportStatisticsBeforeGC(); |
| 1238 | static void ReportStatisticsAfterGC(); |
| 1239 | #endif |
| 1240 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1241 | // Slow part of scavenge object. |
| 1242 | static void ScavengeObjectSlow(HeapObject** p, HeapObject* object); |
| 1243 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1244 | // Initializes a function with a shared part and prototype. |
| 1245 | // Returns the function. |
| 1246 | // Note: this code was factored out of AllocateFunction such that |
| 1247 | // other parts of the VM could use it. Specifically, a function that creates |
| 1248 | // instances of type JS_FUNCTION_TYPE benefit from the use of this function. |
| 1249 | // Please note this does not perform a garbage collection. |
| 1250 | static inline Object* InitializeFunction(JSFunction* function, |
| 1251 | SharedFunctionInfo* shared, |
| 1252 | Object* prototype); |
| 1253 | |
Leon Clarke | f7060e2 | 2010-06-03 12:02:55 +0100 | [diff] [blame] | 1254 | static GCTracer* tracer_; |
| 1255 | |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 1256 | |
| 1257 | // Initializes the number to string cache based on the max semispace size. |
| 1258 | static Object* InitializeNumberStringCache(); |
| 1259 | // Flush the number to string cache. |
| 1260 | static void FlushNumberStringCache(); |
| 1261 | |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 1262 | // Flush code from functions we do not expect to use again. The code will |
| 1263 | // be replaced with a lazy compilable version. |
| 1264 | static void FlushCode(); |
| 1265 | |
Steve Block | 8defd9f | 2010-07-08 12:39:36 +0100 | [diff] [blame] | 1266 | static void UpdateSurvivalRateTrend(int start_new_space_size); |
| 1267 | |
| 1268 | enum SurvivalRateTrend { INCREASING, STABLE, DECREASING, FLUCTUATING }; |
| 1269 | |
| 1270 | static const int kYoungSurvivalRateThreshold = 90; |
| 1271 | static const int kYoungSurvivalRateAllowedDeviation = 15; |
| 1272 | |
| 1273 | static int young_survivors_after_last_gc_; |
| 1274 | static int high_survival_rate_period_length_; |
| 1275 | static double survival_rate_; |
| 1276 | static SurvivalRateTrend previous_survival_rate_trend_; |
| 1277 | static SurvivalRateTrend survival_rate_trend_; |
| 1278 | |
| 1279 | static void set_survival_rate_trend(SurvivalRateTrend survival_rate_trend) { |
| 1280 | ASSERT(survival_rate_trend != FLUCTUATING); |
| 1281 | previous_survival_rate_trend_ = survival_rate_trend_; |
| 1282 | survival_rate_trend_ = survival_rate_trend; |
| 1283 | } |
| 1284 | |
| 1285 | static SurvivalRateTrend survival_rate_trend() { |
| 1286 | if (survival_rate_trend_ == STABLE) { |
| 1287 | return STABLE; |
| 1288 | } else if (previous_survival_rate_trend_ == STABLE) { |
| 1289 | return survival_rate_trend_; |
| 1290 | } else if (survival_rate_trend_ != previous_survival_rate_trend_) { |
| 1291 | return FLUCTUATING; |
| 1292 | } else { |
| 1293 | return survival_rate_trend_; |
| 1294 | } |
| 1295 | } |
| 1296 | |
| 1297 | static bool IsStableOrIncreasingSurvivalTrend() { |
| 1298 | switch (survival_rate_trend()) { |
| 1299 | case STABLE: |
| 1300 | case INCREASING: |
| 1301 | return true; |
| 1302 | default: |
| 1303 | return false; |
| 1304 | } |
| 1305 | } |
| 1306 | |
| 1307 | static bool IsIncreasingSurvivalTrend() { |
| 1308 | return survival_rate_trend() == INCREASING; |
| 1309 | } |
| 1310 | |
| 1311 | static bool IsHighSurvivalRate() { |
| 1312 | return high_survival_rate_period_length_ > 0; |
| 1313 | } |
| 1314 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1315 | static const int kInitialSymbolTableSize = 2048; |
| 1316 | static const int kInitialEvalCacheSize = 64; |
| 1317 | |
| 1318 | friend class Factory; |
| 1319 | friend class DisallowAllocationFailure; |
| 1320 | friend class AlwaysAllocateScope; |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 1321 | friend class LinearAllocationScope; |
| 1322 | }; |
| 1323 | |
| 1324 | |
| 1325 | class HeapStats { |
| 1326 | public: |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1327 | int* start_marker; |
| 1328 | int* new_space_size; |
| 1329 | int* new_space_capacity; |
| 1330 | int* old_pointer_space_size; |
| 1331 | int* old_pointer_space_capacity; |
| 1332 | int* old_data_space_size; |
| 1333 | int* old_data_space_capacity; |
| 1334 | int* code_space_size; |
| 1335 | int* code_space_capacity; |
| 1336 | int* map_space_size; |
| 1337 | int* map_space_capacity; |
| 1338 | int* cell_space_size; |
| 1339 | int* cell_space_capacity; |
| 1340 | int* lo_space_size; |
| 1341 | int* global_handle_count; |
| 1342 | int* weak_global_handle_count; |
| 1343 | int* pending_global_handle_count; |
| 1344 | int* near_death_global_handle_count; |
| 1345 | int* destroyed_global_handle_count; |
| 1346 | int* end_marker; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1347 | }; |
| 1348 | |
| 1349 | |
| 1350 | class AlwaysAllocateScope { |
| 1351 | public: |
| 1352 | AlwaysAllocateScope() { |
| 1353 | // We shouldn't hit any nested scopes, because that requires |
| 1354 | // non-handle code to call handle code. The code still works but |
| 1355 | // performance will degrade, so we want to catch this situation |
| 1356 | // in debug mode. |
| 1357 | ASSERT(Heap::always_allocate_scope_depth_ == 0); |
| 1358 | Heap::always_allocate_scope_depth_++; |
| 1359 | } |
| 1360 | |
| 1361 | ~AlwaysAllocateScope() { |
| 1362 | Heap::always_allocate_scope_depth_--; |
| 1363 | ASSERT(Heap::always_allocate_scope_depth_ == 0); |
| 1364 | } |
| 1365 | }; |
| 1366 | |
| 1367 | |
Steve Block | d0582a6 | 2009-12-15 09:54:21 +0000 | [diff] [blame] | 1368 | class LinearAllocationScope { |
| 1369 | public: |
| 1370 | LinearAllocationScope() { |
| 1371 | Heap::linear_allocation_scope_depth_++; |
| 1372 | } |
| 1373 | |
| 1374 | ~LinearAllocationScope() { |
| 1375 | Heap::linear_allocation_scope_depth_--; |
| 1376 | ASSERT(Heap::linear_allocation_scope_depth_ >= 0); |
| 1377 | } |
| 1378 | }; |
| 1379 | |
| 1380 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1381 | #ifdef DEBUG |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 1382 | // Visitor class to verify interior pointers in spaces that do not contain |
| 1383 | // or care about intergenerational references. All heap object pointers have to |
| 1384 | // point into the heap to a location that has a map pointer at its first word. |
| 1385 | // Caveat: Heap::Contains is an approximation because it can return true for |
| 1386 | // objects in a heap space but above the allocation pointer. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1387 | class VerifyPointersVisitor: public ObjectVisitor { |
| 1388 | public: |
| 1389 | void VisitPointers(Object** start, Object** end) { |
| 1390 | for (Object** current = start; current < end; current++) { |
| 1391 | if ((*current)->IsHeapObject()) { |
| 1392 | HeapObject* object = HeapObject::cast(*current); |
| 1393 | ASSERT(Heap::Contains(object)); |
| 1394 | ASSERT(object->map()->IsMap()); |
| 1395 | } |
| 1396 | } |
| 1397 | } |
| 1398 | }; |
| 1399 | |
| 1400 | |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 1401 | // Visitor class to verify interior pointers in spaces that use region marks |
| 1402 | // to keep track of intergenerational references. |
| 1403 | // As VerifyPointersVisitor but also checks that dirty marks are set |
| 1404 | // for regions covering intergenerational references. |
| 1405 | class VerifyPointersAndDirtyRegionsVisitor: public ObjectVisitor { |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1406 | public: |
| 1407 | void VisitPointers(Object** start, Object** end) { |
| 1408 | for (Object** current = start; current < end; current++) { |
| 1409 | if ((*current)->IsHeapObject()) { |
| 1410 | HeapObject* object = HeapObject::cast(*current); |
| 1411 | ASSERT(Heap::Contains(object)); |
| 1412 | ASSERT(object->map()->IsMap()); |
| 1413 | if (Heap::InNewSpace(object)) { |
Ben Murdoch | 7f4d5bd | 2010-06-15 11:15:29 +0100 | [diff] [blame] | 1414 | ASSERT(Heap::InToSpace(object)); |
| 1415 | Address addr = reinterpret_cast<Address>(current); |
| 1416 | ASSERT(Page::FromAddress(addr)->IsRegionDirty(addr)); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1417 | } |
| 1418 | } |
| 1419 | } |
| 1420 | } |
| 1421 | }; |
| 1422 | #endif |
| 1423 | |
| 1424 | |
| 1425 | // Space iterator for iterating over all spaces of the heap. |
| 1426 | // Returns each space in turn, and null when it is done. |
| 1427 | class AllSpaces BASE_EMBEDDED { |
| 1428 | public: |
| 1429 | Space* next(); |
| 1430 | AllSpaces() { counter_ = FIRST_SPACE; } |
| 1431 | private: |
| 1432 | int counter_; |
| 1433 | }; |
| 1434 | |
| 1435 | |
| 1436 | // Space iterator for iterating over all old spaces of the heap: Old pointer |
| 1437 | // space, old data space and code space. |
| 1438 | // Returns each space in turn, and null when it is done. |
| 1439 | class OldSpaces BASE_EMBEDDED { |
| 1440 | public: |
| 1441 | OldSpace* next(); |
| 1442 | OldSpaces() { counter_ = OLD_POINTER_SPACE; } |
| 1443 | private: |
| 1444 | int counter_; |
| 1445 | }; |
| 1446 | |
| 1447 | |
| 1448 | // Space iterator for iterating over all the paged spaces of the heap: |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 1449 | // Map space, old pointer space, old data space, code space and cell space. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1450 | // Returns each space in turn, and null when it is done. |
| 1451 | class PagedSpaces BASE_EMBEDDED { |
| 1452 | public: |
| 1453 | PagedSpace* next(); |
| 1454 | PagedSpaces() { counter_ = OLD_POINTER_SPACE; } |
| 1455 | private: |
| 1456 | int counter_; |
| 1457 | }; |
| 1458 | |
| 1459 | |
| 1460 | // Space iterator for iterating over all spaces of the heap. |
| 1461 | // For each space an object iterator is provided. The deallocation of the |
| 1462 | // returned object iterators is handled by the space iterator. |
| 1463 | class SpaceIterator : public Malloced { |
| 1464 | public: |
| 1465 | SpaceIterator(); |
| 1466 | virtual ~SpaceIterator(); |
| 1467 | |
| 1468 | bool has_next(); |
| 1469 | ObjectIterator* next(); |
| 1470 | |
| 1471 | private: |
| 1472 | ObjectIterator* CreateIterator(); |
| 1473 | |
| 1474 | int current_space_; // from enum AllocationSpace. |
| 1475 | ObjectIterator* iterator_; // object iterator for the current space. |
| 1476 | }; |
| 1477 | |
| 1478 | |
| 1479 | // A HeapIterator provides iteration over the whole heap It aggregates a the |
| 1480 | // specific iterators for the different spaces as these can only iterate over |
| 1481 | // one space only. |
| 1482 | |
| 1483 | class HeapIterator BASE_EMBEDDED { |
| 1484 | public: |
| 1485 | explicit HeapIterator(); |
| 1486 | virtual ~HeapIterator(); |
| 1487 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1488 | HeapObject* next(); |
| 1489 | void reset(); |
| 1490 | |
| 1491 | private: |
| 1492 | // Perform the initialization. |
| 1493 | void Init(); |
| 1494 | |
| 1495 | // Perform all necessary shutdown (destruction) work. |
| 1496 | void Shutdown(); |
| 1497 | |
| 1498 | // Space iterator for iterating all the spaces. |
| 1499 | SpaceIterator* space_iterator_; |
| 1500 | // Object iterator for the space currently being iterated. |
| 1501 | ObjectIterator* object_iterator_; |
| 1502 | }; |
| 1503 | |
| 1504 | |
| 1505 | // Cache for mapping (map, property name) into field offset. |
| 1506 | // Cleared at startup and prior to mark sweep collection. |
| 1507 | class KeyedLookupCache { |
| 1508 | public: |
| 1509 | // Lookup field offset for (map, name). If absent, -1 is returned. |
| 1510 | static int Lookup(Map* map, String* name); |
| 1511 | |
| 1512 | // Update an element in the cache. |
| 1513 | static void Update(Map* map, String* name, int field_offset); |
| 1514 | |
| 1515 | // Clear the cache. |
| 1516 | static void Clear(); |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 1517 | |
| 1518 | static const int kLength = 64; |
| 1519 | static const int kCapacityMask = kLength - 1; |
| 1520 | static const int kMapHashShift = 2; |
| 1521 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1522 | private: |
| 1523 | static inline int Hash(Map* map, String* name); |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 1524 | |
| 1525 | // Get the address of the keys and field_offsets arrays. Used in |
| 1526 | // generated code to perform cache lookups. |
| 1527 | static Address keys_address() { |
| 1528 | return reinterpret_cast<Address>(&keys_); |
| 1529 | } |
| 1530 | |
| 1531 | static Address field_offsets_address() { |
| 1532 | return reinterpret_cast<Address>(&field_offsets_); |
| 1533 | } |
| 1534 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1535 | struct Key { |
| 1536 | Map* map; |
| 1537 | String* name; |
| 1538 | }; |
| 1539 | static Key keys_[kLength]; |
| 1540 | static int field_offsets_[kLength]; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1541 | |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 1542 | friend class ExternalReference; |
| 1543 | }; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1544 | |
| 1545 | |
| 1546 | // Cache for mapping (array, property name) into descriptor index. |
| 1547 | // The cache contains both positive and negative results. |
| 1548 | // Descriptor index equals kNotFound means the property is absent. |
| 1549 | // Cleared at startup and prior to any gc. |
| 1550 | class DescriptorLookupCache { |
| 1551 | public: |
| 1552 | // Lookup descriptor index for (map, name). |
| 1553 | // If absent, kAbsent is returned. |
| 1554 | static int Lookup(DescriptorArray* array, String* name) { |
| 1555 | if (!StringShape(name).IsSymbol()) return kAbsent; |
| 1556 | int index = Hash(array, name); |
| 1557 | Key& key = keys_[index]; |
| 1558 | if ((key.array == array) && (key.name == name)) return results_[index]; |
| 1559 | return kAbsent; |
| 1560 | } |
| 1561 | |
| 1562 | // Update an element in the cache. |
| 1563 | static void Update(DescriptorArray* array, String* name, int result) { |
| 1564 | ASSERT(result != kAbsent); |
| 1565 | if (StringShape(name).IsSymbol()) { |
| 1566 | int index = Hash(array, name); |
| 1567 | Key& key = keys_[index]; |
| 1568 | key.array = array; |
| 1569 | key.name = name; |
| 1570 | results_[index] = result; |
| 1571 | } |
| 1572 | } |
| 1573 | |
| 1574 | // Clear the cache. |
| 1575 | static void Clear(); |
| 1576 | |
| 1577 | static const int kAbsent = -2; |
| 1578 | private: |
| 1579 | static int Hash(DescriptorArray* array, String* name) { |
| 1580 | // Uses only lower 32 bits if pointers are larger. |
Andrei Popescu | 402d937 | 2010-02-26 13:31:12 +0000 | [diff] [blame] | 1581 | uint32_t array_hash = |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1582 | static_cast<uint32_t>(reinterpret_cast<uintptr_t>(array)) >> 2; |
Andrei Popescu | 402d937 | 2010-02-26 13:31:12 +0000 | [diff] [blame] | 1583 | uint32_t name_hash = |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1584 | static_cast<uint32_t>(reinterpret_cast<uintptr_t>(name)) >> 2; |
| 1585 | return (array_hash ^ name_hash) % kLength; |
| 1586 | } |
| 1587 | |
| 1588 | static const int kLength = 64; |
| 1589 | struct Key { |
| 1590 | DescriptorArray* array; |
| 1591 | String* name; |
| 1592 | }; |
| 1593 | |
| 1594 | static Key keys_[kLength]; |
| 1595 | static int results_[kLength]; |
| 1596 | }; |
| 1597 | |
| 1598 | |
| 1599 | // ---------------------------------------------------------------------------- |
| 1600 | // Marking stack for tracing live objects. |
| 1601 | |
| 1602 | class MarkingStack { |
| 1603 | public: |
| 1604 | void Initialize(Address low, Address high) { |
| 1605 | top_ = low_ = reinterpret_cast<HeapObject**>(low); |
| 1606 | high_ = reinterpret_cast<HeapObject**>(high); |
| 1607 | overflowed_ = false; |
| 1608 | } |
| 1609 | |
| 1610 | bool is_full() { return top_ >= high_; } |
| 1611 | |
| 1612 | bool is_empty() { return top_ <= low_; } |
| 1613 | |
| 1614 | bool overflowed() { return overflowed_; } |
| 1615 | |
| 1616 | void clear_overflowed() { overflowed_ = false; } |
| 1617 | |
| 1618 | // Push the (marked) object on the marking stack if there is room, |
| 1619 | // otherwise mark the object as overflowed and wait for a rescan of the |
| 1620 | // heap. |
| 1621 | void Push(HeapObject* object) { |
| 1622 | CHECK(object->IsHeapObject()); |
| 1623 | if (is_full()) { |
| 1624 | object->SetOverflow(); |
| 1625 | overflowed_ = true; |
| 1626 | } else { |
| 1627 | *(top_++) = object; |
| 1628 | } |
| 1629 | } |
| 1630 | |
| 1631 | HeapObject* Pop() { |
| 1632 | ASSERT(!is_empty()); |
| 1633 | HeapObject* object = *(--top_); |
| 1634 | CHECK(object->IsHeapObject()); |
| 1635 | return object; |
| 1636 | } |
| 1637 | |
| 1638 | private: |
| 1639 | HeapObject** low_; |
| 1640 | HeapObject** top_; |
| 1641 | HeapObject** high_; |
| 1642 | bool overflowed_; |
| 1643 | }; |
| 1644 | |
| 1645 | |
| 1646 | // A helper class to document/test C++ scopes where we do not |
| 1647 | // expect a GC. Usage: |
| 1648 | // |
| 1649 | // /* Allocation not allowed: we cannot handle a GC in this scope. */ |
| 1650 | // { AssertNoAllocation nogc; |
| 1651 | // ... |
| 1652 | // } |
| 1653 | |
| 1654 | #ifdef DEBUG |
| 1655 | |
| 1656 | class DisallowAllocationFailure { |
| 1657 | public: |
| 1658 | DisallowAllocationFailure() { |
| 1659 | old_state_ = Heap::disallow_allocation_failure_; |
| 1660 | Heap::disallow_allocation_failure_ = true; |
| 1661 | } |
| 1662 | ~DisallowAllocationFailure() { |
| 1663 | Heap::disallow_allocation_failure_ = old_state_; |
| 1664 | } |
| 1665 | private: |
| 1666 | bool old_state_; |
| 1667 | }; |
| 1668 | |
| 1669 | class AssertNoAllocation { |
| 1670 | public: |
| 1671 | AssertNoAllocation() { |
| 1672 | old_state_ = Heap::allow_allocation(false); |
| 1673 | } |
| 1674 | |
| 1675 | ~AssertNoAllocation() { |
| 1676 | Heap::allow_allocation(old_state_); |
| 1677 | } |
| 1678 | |
| 1679 | private: |
| 1680 | bool old_state_; |
| 1681 | }; |
| 1682 | |
| 1683 | class DisableAssertNoAllocation { |
| 1684 | public: |
| 1685 | DisableAssertNoAllocation() { |
| 1686 | old_state_ = Heap::allow_allocation(true); |
| 1687 | } |
| 1688 | |
| 1689 | ~DisableAssertNoAllocation() { |
| 1690 | Heap::allow_allocation(old_state_); |
| 1691 | } |
| 1692 | |
| 1693 | private: |
| 1694 | bool old_state_; |
| 1695 | }; |
| 1696 | |
| 1697 | #else // ndef DEBUG |
| 1698 | |
| 1699 | class AssertNoAllocation { |
| 1700 | public: |
| 1701 | AssertNoAllocation() { } |
| 1702 | ~AssertNoAllocation() { } |
| 1703 | }; |
| 1704 | |
| 1705 | class DisableAssertNoAllocation { |
| 1706 | public: |
| 1707 | DisableAssertNoAllocation() { } |
| 1708 | ~DisableAssertNoAllocation() { } |
| 1709 | }; |
| 1710 | |
| 1711 | #endif |
| 1712 | |
| 1713 | // GCTracer collects and prints ONE line after each garbage collector |
| 1714 | // invocation IFF --trace_gc is used. |
| 1715 | |
| 1716 | class GCTracer BASE_EMBEDDED { |
| 1717 | public: |
Leon Clarke | f7060e2 | 2010-06-03 12:02:55 +0100 | [diff] [blame] | 1718 | class Scope BASE_EMBEDDED { |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1719 | public: |
Leon Clarke | f7060e2 | 2010-06-03 12:02:55 +0100 | [diff] [blame] | 1720 | enum ScopeId { |
| 1721 | EXTERNAL, |
| 1722 | MC_MARK, |
| 1723 | MC_SWEEP, |
| 1724 | MC_COMPACT, |
| 1725 | kNumberOfScopes |
| 1726 | }; |
| 1727 | |
| 1728 | Scope(GCTracer* tracer, ScopeId scope) |
| 1729 | : tracer_(tracer), |
| 1730 | scope_(scope) { |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1731 | start_time_ = OS::TimeCurrentMillis(); |
| 1732 | } |
Leon Clarke | f7060e2 | 2010-06-03 12:02:55 +0100 | [diff] [blame] | 1733 | |
| 1734 | ~Scope() { |
| 1735 | ASSERT((0 <= scope_) && (scope_ < kNumberOfScopes)); |
| 1736 | tracer_->scopes_[scope_] += OS::TimeCurrentMillis() - start_time_; |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1737 | } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1738 | |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1739 | private: |
| 1740 | GCTracer* tracer_; |
Leon Clarke | f7060e2 | 2010-06-03 12:02:55 +0100 | [diff] [blame] | 1741 | ScopeId scope_; |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1742 | double start_time_; |
| 1743 | }; |
| 1744 | |
| 1745 | GCTracer(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1746 | ~GCTracer(); |
| 1747 | |
| 1748 | // Sets the collector. |
| 1749 | void set_collector(GarbageCollector collector) { collector_ = collector; } |
| 1750 | |
| 1751 | // Sets the GC count. |
| 1752 | void set_gc_count(int count) { gc_count_ = count; } |
| 1753 | |
| 1754 | // Sets the full GC count. |
| 1755 | void set_full_gc_count(int count) { full_gc_count_ = count; } |
| 1756 | |
| 1757 | // Sets the flag that this is a compacting full GC. |
| 1758 | void set_is_compacting() { is_compacting_ = true; } |
Steve Block | 6ded16b | 2010-05-10 14:33:55 +0100 | [diff] [blame] | 1759 | bool is_compacting() const { return is_compacting_; } |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1760 | |
| 1761 | // Increment and decrement the count of marked objects. |
| 1762 | void increment_marked_count() { ++marked_count_; } |
| 1763 | void decrement_marked_count() { --marked_count_; } |
| 1764 | |
| 1765 | int marked_count() { return marked_count_; } |
| 1766 | |
Leon Clarke | f7060e2 | 2010-06-03 12:02:55 +0100 | [diff] [blame] | 1767 | void increment_promoted_objects_size(int object_size) { |
| 1768 | promoted_objects_size_ += object_size; |
| 1769 | } |
| 1770 | |
| 1771 | // Returns maximum GC pause. |
| 1772 | static int get_max_gc_pause() { return max_gc_pause_; } |
| 1773 | |
| 1774 | // Returns maximum size of objects alive after GC. |
| 1775 | static int get_max_alive_after_gc() { return max_alive_after_gc_; } |
| 1776 | |
| 1777 | // Returns minimal interval between two subsequent collections. |
| 1778 | static int get_min_in_mutator() { return min_in_mutator_; } |
| 1779 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1780 | private: |
| 1781 | // Returns a string matching the collector. |
| 1782 | const char* CollectorString(); |
| 1783 | |
| 1784 | // Returns size of object in heap (in MB). |
| 1785 | double SizeOfHeapObjects() { |
| 1786 | return (static_cast<double>(Heap::SizeOfObjects())) / MB; |
| 1787 | } |
| 1788 | |
| 1789 | double start_time_; // Timestamp set in the constructor. |
Leon Clarke | f7060e2 | 2010-06-03 12:02:55 +0100 | [diff] [blame] | 1790 | int start_size_; // Size of objects in heap set in constructor. |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1791 | GarbageCollector collector_; // Type of collector. |
| 1792 | |
| 1793 | // A count (including this one, eg, the first collection is 1) of the |
| 1794 | // number of garbage collections. |
| 1795 | int gc_count_; |
| 1796 | |
| 1797 | // A count (including this one) of the number of full garbage collections. |
| 1798 | int full_gc_count_; |
| 1799 | |
| 1800 | // True if the current GC is a compacting full collection, false |
| 1801 | // otherwise. |
| 1802 | bool is_compacting_; |
| 1803 | |
| 1804 | // True if the *previous* full GC cwas a compacting collection (will be |
| 1805 | // false if there has not been a previous full GC). |
| 1806 | bool previous_has_compacted_; |
| 1807 | |
| 1808 | // On a full GC, a count of the number of marked objects. Incremented |
| 1809 | // when an object is marked and decremented when an object's mark bit is |
| 1810 | // cleared. Will be zero on a scavenge collection. |
| 1811 | int marked_count_; |
| 1812 | |
| 1813 | // The count from the end of the previous full GC. Will be zero if there |
| 1814 | // was no previous full GC. |
| 1815 | int previous_marked_count_; |
Leon Clarke | f7060e2 | 2010-06-03 12:02:55 +0100 | [diff] [blame] | 1816 | |
| 1817 | // Amounts of time spent in different scopes during GC. |
| 1818 | double scopes_[Scope::kNumberOfScopes]; |
| 1819 | |
| 1820 | // Total amount of space either wasted or contained in one of free lists |
| 1821 | // before the current GC. |
| 1822 | int in_free_list_or_wasted_before_gc_; |
| 1823 | |
| 1824 | // Difference between space used in the heap at the beginning of the current |
| 1825 | // collection and the end of the previous collection. |
| 1826 | int allocated_since_last_gc_; |
| 1827 | |
| 1828 | // Amount of time spent in mutator that is time elapsed between end of the |
| 1829 | // previous collection and the beginning of the current one. |
| 1830 | double spent_in_mutator_; |
| 1831 | |
| 1832 | // Size of objects promoted during the current collection. |
| 1833 | int promoted_objects_size_; |
| 1834 | |
| 1835 | // Maximum GC pause. |
| 1836 | static int max_gc_pause_; |
| 1837 | |
| 1838 | // Maximum size of objects alive after GC. |
| 1839 | static int max_alive_after_gc_; |
| 1840 | |
| 1841 | // Minimal interval between two subsequent collections. |
| 1842 | static int min_in_mutator_; |
| 1843 | |
| 1844 | // Size of objects alive after last GC. |
| 1845 | static int alive_after_last_gc_; |
| 1846 | |
| 1847 | static double last_gc_end_timestamp_; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1848 | }; |
| 1849 | |
| 1850 | |
| 1851 | class TranscendentalCache { |
| 1852 | public: |
| 1853 | enum Type {ACOS, ASIN, ATAN, COS, EXP, LOG, SIN, TAN, kNumberOfCaches}; |
| 1854 | |
| 1855 | explicit TranscendentalCache(Type t); |
| 1856 | |
| 1857 | // Returns a heap number with f(input), where f is a math function specified |
| 1858 | // by the 'type' argument. |
| 1859 | static inline Object* Get(Type type, double input) { |
| 1860 | TranscendentalCache* cache = caches_[type]; |
| 1861 | if (cache == NULL) { |
| 1862 | caches_[type] = cache = new TranscendentalCache(type); |
| 1863 | } |
| 1864 | return cache->Get(input); |
| 1865 | } |
| 1866 | |
| 1867 | // The cache contains raw Object pointers. This method disposes of |
| 1868 | // them before a garbage collection. |
| 1869 | static void Clear(); |
| 1870 | |
| 1871 | private: |
| 1872 | inline Object* Get(double input) { |
| 1873 | Converter c; |
| 1874 | c.dbl = input; |
| 1875 | int hash = Hash(c); |
| 1876 | Element e = elements_[hash]; |
| 1877 | if (e.in[0] == c.integers[0] && |
| 1878 | e.in[1] == c.integers[1]) { |
| 1879 | ASSERT(e.output != NULL); |
Andrei Popescu | 402d937 | 2010-02-26 13:31:12 +0000 | [diff] [blame] | 1880 | Counters::transcendental_cache_hit.Increment(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1881 | return e.output; |
| 1882 | } |
| 1883 | double answer = Calculate(input); |
| 1884 | Object* heap_number = Heap::AllocateHeapNumber(answer); |
| 1885 | if (!heap_number->IsFailure()) { |
| 1886 | elements_[hash].in[0] = c.integers[0]; |
| 1887 | elements_[hash].in[1] = c.integers[1]; |
| 1888 | elements_[hash].output = heap_number; |
| 1889 | } |
Andrei Popescu | 402d937 | 2010-02-26 13:31:12 +0000 | [diff] [blame] | 1890 | Counters::transcendental_cache_miss.Increment(); |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1891 | return heap_number; |
| 1892 | } |
| 1893 | |
| 1894 | inline double Calculate(double input) { |
| 1895 | switch (type_) { |
| 1896 | case ACOS: |
| 1897 | return acos(input); |
| 1898 | case ASIN: |
| 1899 | return asin(input); |
| 1900 | case ATAN: |
| 1901 | return atan(input); |
| 1902 | case COS: |
| 1903 | return cos(input); |
| 1904 | case EXP: |
| 1905 | return exp(input); |
| 1906 | case LOG: |
| 1907 | return log(input); |
| 1908 | case SIN: |
| 1909 | return sin(input); |
| 1910 | case TAN: |
| 1911 | return tan(input); |
| 1912 | default: |
| 1913 | return 0.0; // Never happens. |
| 1914 | } |
| 1915 | } |
| 1916 | static const int kCacheSize = 512; |
| 1917 | struct Element { |
| 1918 | uint32_t in[2]; |
| 1919 | Object* output; |
| 1920 | }; |
| 1921 | union Converter { |
| 1922 | double dbl; |
| 1923 | uint32_t integers[2]; |
| 1924 | }; |
| 1925 | inline static int Hash(const Converter& c) { |
| 1926 | uint32_t hash = (c.integers[0] ^ c.integers[1]); |
Kristian Monsen | 9dcf7e2 | 2010-06-28 14:14:28 +0100 | [diff] [blame] | 1927 | hash ^= static_cast<int32_t>(hash) >> 16; |
| 1928 | hash ^= static_cast<int32_t>(hash) >> 8; |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1929 | return (hash & (kCacheSize - 1)); |
| 1930 | } |
Andrei Popescu | 402d937 | 2010-02-26 13:31:12 +0000 | [diff] [blame] | 1931 | |
| 1932 | static Address cache_array_address() { |
| 1933 | // Used to create an external reference. |
| 1934 | return reinterpret_cast<Address>(caches_); |
| 1935 | } |
| 1936 | |
| 1937 | // Allow access to the caches_ array as an ExternalReference. |
| 1938 | friend class ExternalReference; |
| 1939 | // Inline implementation of the caching. |
| 1940 | friend class TranscendentalCacheStub; |
| 1941 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1942 | static TranscendentalCache* caches_[kNumberOfCaches]; |
| 1943 | Element elements_[kCacheSize]; |
| 1944 | Type type_; |
| 1945 | }; |
| 1946 | |
| 1947 | |
Leon Clarke | e46be81 | 2010-01-19 14:06:41 +0000 | [diff] [blame] | 1948 | // External strings table is a place where all external strings are |
| 1949 | // registered. We need to keep track of such strings to properly |
| 1950 | // finalize them. |
| 1951 | class ExternalStringTable : public AllStatic { |
| 1952 | public: |
| 1953 | // Registers an external string. |
| 1954 | inline static void AddString(String* string); |
| 1955 | |
| 1956 | inline static void Iterate(ObjectVisitor* v); |
| 1957 | |
| 1958 | // Restores internal invariant and gets rid of collected strings. |
| 1959 | // Must be called after each Iterate() that modified the strings. |
| 1960 | static void CleanUp(); |
| 1961 | |
| 1962 | // Destroys all allocated memory. |
| 1963 | static void TearDown(); |
| 1964 | |
| 1965 | private: |
| 1966 | friend class Heap; |
| 1967 | |
| 1968 | inline static void Verify(); |
| 1969 | |
| 1970 | inline static void AddOldString(String* string); |
| 1971 | |
| 1972 | // Notifies the table that only a prefix of the new list is valid. |
| 1973 | inline static void ShrinkNewStrings(int position); |
| 1974 | |
| 1975 | // To speed up scavenge collections new space string are kept |
| 1976 | // separate from old space strings. |
| 1977 | static List<Object*> new_space_strings_; |
| 1978 | static List<Object*> old_space_strings_; |
| 1979 | }; |
| 1980 | |
Steve Block | a7e24c1 | 2009-10-30 11:49:00 +0000 | [diff] [blame] | 1981 | } } // namespace v8::internal |
| 1982 | |
| 1983 | #endif // V8_HEAP_H_ |