| File: | out/../deps/v8/src/compiler/scheduler.cc |
| Warning: | line 1229, column 14 Although the value stored to 'b2' is used in the enclosing expression, the value is never actually read from 'b2' |
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| 1 | // Copyright 2013 the V8 project authors. All rights reserved. |
| 2 | // Use of this source code is governed by a BSD-style license that can be |
| 3 | // found in the LICENSE file. |
| 4 | |
| 5 | #include "src/compiler/scheduler.h" |
| 6 | |
| 7 | #include <iomanip> |
| 8 | |
| 9 | #include "src/base/iterator.h" |
| 10 | #include "src/builtins/profile-data-reader.h" |
| 11 | #include "src/codegen/tick-counter.h" |
| 12 | #include "src/compiler/common-operator.h" |
| 13 | #include "src/compiler/control-equivalence.h" |
| 14 | #include "src/compiler/graph.h" |
| 15 | #include "src/compiler/node-marker.h" |
| 16 | #include "src/compiler/node-properties.h" |
| 17 | #include "src/compiler/node.h" |
| 18 | #include "src/utils/bit-vector.h" |
| 19 | #include "src/zone/zone-containers.h" |
| 20 | |
| 21 | namespace v8 { |
| 22 | namespace internal { |
| 23 | namespace compiler { |
| 24 | |
| 25 | #define TRACE(...) \ |
| 26 | do { \ |
| 27 | if (FLAG_trace_turbo_scheduler) PrintF(__VA_ARGS__); \ |
| 28 | } while (false) |
| 29 | |
| 30 | Scheduler::Scheduler(Zone* zone, Graph* graph, Schedule* schedule, Flags flags, |
| 31 | size_t node_count_hint, TickCounter* tick_counter, |
| 32 | const ProfileDataFromFile* profile_data) |
| 33 | : zone_(zone), |
| 34 | graph_(graph), |
| 35 | schedule_(schedule), |
| 36 | flags_(flags), |
| 37 | scheduled_nodes_(zone), |
| 38 | schedule_root_nodes_(zone), |
| 39 | schedule_queue_(zone), |
| 40 | node_data_(zone), |
| 41 | tick_counter_(tick_counter), |
| 42 | profile_data_(profile_data), |
| 43 | common_dominator_cache_(zone) { |
| 44 | node_data_.reserve(node_count_hint); |
| 45 | node_data_.resize(graph->NodeCount(), DefaultSchedulerData()); |
| 46 | } |
| 47 | |
| 48 | Schedule* Scheduler::ComputeSchedule(Zone* zone, Graph* graph, Flags flags, |
| 49 | TickCounter* tick_counter, |
| 50 | const ProfileDataFromFile* profile_data) { |
| 51 | Zone* schedule_zone = |
| 52 | (flags & Scheduler::kTempSchedule) ? zone : graph->zone(); |
| 53 | |
| 54 | // Reserve 10% more space for nodes if node splitting is enabled to try to |
| 55 | // avoid resizing the vector since that would triple its zone memory usage. |
| 56 | float node_hint_multiplier = (flags & Scheduler::kSplitNodes) ? 1.1 : 1; |
| 57 | size_t node_count_hint = node_hint_multiplier * graph->NodeCount(); |
| 58 | |
| 59 | Schedule* schedule = |
| 60 | schedule_zone->New<Schedule>(schedule_zone, node_count_hint); |
| 61 | Scheduler scheduler(zone, graph, schedule, flags, node_count_hint, |
| 62 | tick_counter, profile_data); |
| 63 | |
| 64 | scheduler.BuildCFG(); |
| 65 | scheduler.ComputeSpecialRPONumbering(); |
| 66 | scheduler.GenerateDominatorTree(); |
| 67 | |
| 68 | scheduler.PrepareUses(); |
| 69 | scheduler.ScheduleEarly(); |
| 70 | scheduler.ScheduleLate(); |
| 71 | |
| 72 | scheduler.SealFinalSchedule(); |
| 73 | |
| 74 | return schedule; |
| 75 | } |
| 76 | |
| 77 | Scheduler::SchedulerData Scheduler::DefaultSchedulerData() { |
| 78 | SchedulerData def = {schedule_->start(), 0, kUnknown}; |
| 79 | return def; |
| 80 | } |
| 81 | |
| 82 | |
| 83 | Scheduler::SchedulerData* Scheduler::GetData(Node* node) { |
| 84 | return &node_data_[node->id()]; |
| 85 | } |
| 86 | |
| 87 | Scheduler::Placement Scheduler::InitializePlacement(Node* node) { |
| 88 | SchedulerData* data = GetData(node); |
| 89 | if (data->placement_ == kFixed) { |
| 90 | // Nothing to do for control nodes that have been already fixed in |
| 91 | // the schedule. |
| 92 | return data->placement_; |
| 93 | } |
| 94 | DCHECK_EQ(kUnknown, data->placement_)((void) 0); |
| 95 | switch (node->opcode()) { |
| 96 | case IrOpcode::kParameter: |
| 97 | case IrOpcode::kOsrValue: |
| 98 | // Parameters and OSR values are always fixed to the start block. |
| 99 | data->placement_ = kFixed; |
| 100 | break; |
| 101 | case IrOpcode::kPhi: |
| 102 | case IrOpcode::kEffectPhi: { |
| 103 | // Phis and effect phis are fixed if their control inputs are, whereas |
| 104 | // otherwise they are coupled to a floating control node. |
| 105 | Placement p = GetPlacement(NodeProperties::GetControlInput(node)); |
| 106 | data->placement_ = (p == kFixed ? kFixed : kCoupled); |
| 107 | break; |
| 108 | } |
| 109 | default: |
| 110 | // Control nodes that were not control-reachable from end may float. |
| 111 | data->placement_ = kSchedulable; |
| 112 | break; |
| 113 | } |
| 114 | return data->placement_; |
| 115 | } |
| 116 | |
| 117 | Scheduler::Placement Scheduler::GetPlacement(Node* node) { |
| 118 | return GetData(node)->placement_; |
| 119 | } |
| 120 | |
| 121 | bool Scheduler::IsLive(Node* node) { return GetPlacement(node) != kUnknown; } |
| 122 | |
| 123 | void Scheduler::UpdatePlacement(Node* node, Placement placement) { |
| 124 | SchedulerData* data = GetData(node); |
| 125 | if (data->placement_ == kUnknown) { |
| 126 | // We only update control nodes from {kUnknown} to {kFixed}. Ideally, we |
| 127 | // should check that {node} is a control node (including exceptional calls), |
| 128 | // but that is expensive. |
| 129 | DCHECK_EQ(Scheduler::kFixed, placement)((void) 0); |
| 130 | data->placement_ = placement; |
| 131 | return; |
| 132 | } |
| 133 | |
| 134 | switch (node->opcode()) { |
| 135 | case IrOpcode::kParameter: |
| 136 | // Parameters are fixed once and for all. |
| 137 | UNREACHABLE()V8_Fatal("unreachable code"); |
| 138 | case IrOpcode::kPhi: |
| 139 | case IrOpcode::kEffectPhi: { |
| 140 | // Phis and effect phis are coupled to their respective blocks. |
| 141 | DCHECK_EQ(Scheduler::kCoupled, data->placement_)((void) 0); |
| 142 | DCHECK_EQ(Scheduler::kFixed, placement)((void) 0); |
| 143 | Node* control = NodeProperties::GetControlInput(node); |
| 144 | BasicBlock* block = schedule_->block(control); |
| 145 | schedule_->AddNode(block, node); |
| 146 | break; |
| 147 | } |
| 148 | #define DEFINE_CONTROL_CASE(V) case IrOpcode::k##V: |
| 149 | CONTROL_OP_LIST(DEFINE_CONTROL_CASE)DEFINE_CONTROL_CASE(Start) DEFINE_CONTROL_CASE(Loop) DEFINE_CONTROL_CASE (Branch) DEFINE_CONTROL_CASE(Switch) DEFINE_CONTROL_CASE(IfTrue ) DEFINE_CONTROL_CASE(IfFalse) DEFINE_CONTROL_CASE(IfSuccess) DEFINE_CONTROL_CASE(IfException) DEFINE_CONTROL_CASE(IfValue ) DEFINE_CONTROL_CASE(IfDefault) DEFINE_CONTROL_CASE(Merge) DEFINE_CONTROL_CASE (Deoptimize) DEFINE_CONTROL_CASE(DeoptimizeIf) DEFINE_CONTROL_CASE (DeoptimizeUnless) DEFINE_CONTROL_CASE(TrapIf) DEFINE_CONTROL_CASE (TrapUnless) DEFINE_CONTROL_CASE(Return) DEFINE_CONTROL_CASE( TailCall) DEFINE_CONTROL_CASE(Terminate) DEFINE_CONTROL_CASE( Throw) DEFINE_CONTROL_CASE(End) |
| 150 | #undef DEFINE_CONTROL_CASE |
| 151 | { |
| 152 | // Control nodes force coupled uses to be placed. |
| 153 | for (auto use : node->uses()) { |
| 154 | if (GetPlacement(use) == Scheduler::kCoupled) { |
| 155 | DCHECK_EQ(node, NodeProperties::GetControlInput(use))((void) 0); |
| 156 | UpdatePlacement(use, placement); |
| 157 | } |
| 158 | } |
| 159 | break; |
| 160 | } |
| 161 | default: |
| 162 | DCHECK_EQ(Scheduler::kSchedulable, data->placement_)((void) 0); |
| 163 | DCHECK_EQ(Scheduler::kScheduled, placement)((void) 0); |
| 164 | break; |
| 165 | } |
| 166 | // Reduce the use count of the node's inputs to potentially make them |
| 167 | // schedulable. If all the uses of a node have been scheduled, then the node |
| 168 | // itself can be scheduled. |
| 169 | base::Optional<int> coupled_control_edge = GetCoupledControlEdge(node); |
| 170 | for (Edge const edge : node->input_edges()) { |
| 171 | DCHECK_EQ(node, edge.from())((void) 0); |
| 172 | if (edge.index() != coupled_control_edge) { |
| 173 | DecrementUnscheduledUseCount(edge.to(), node); |
| 174 | } |
| 175 | } |
| 176 | data->placement_ = placement; |
| 177 | } |
| 178 | |
| 179 | base::Optional<int> Scheduler::GetCoupledControlEdge(Node* node) { |
| 180 | if (GetPlacement(node) == kCoupled) { |
| 181 | return NodeProperties::FirstControlIndex(node); |
| 182 | } |
| 183 | return {}; |
| 184 | } |
| 185 | |
| 186 | void Scheduler::IncrementUnscheduledUseCount(Node* node, Node* from) { |
| 187 | // Tracking use counts for fixed nodes is useless. |
| 188 | if (GetPlacement(node) == kFixed) return; |
| 189 | |
| 190 | // Use count for coupled nodes is summed up on their control. |
| 191 | if (GetPlacement(node) == kCoupled) { |
| 192 | node = NodeProperties::GetControlInput(node); |
| 193 | DCHECK_NE(GetPlacement(node), Placement::kFixed)((void) 0); |
| 194 | DCHECK_NE(GetPlacement(node), Placement::kCoupled)((void) 0); |
| 195 | } |
| 196 | |
| 197 | ++(GetData(node)->unscheduled_count_); |
| 198 | if (FLAG_trace_turbo_scheduler) { |
| 199 | TRACE(" Use count of #%d:%s (used by #%d:%s)++ = %d\n", node->id(), |
| 200 | node->op()->mnemonic(), from->id(), from->op()->mnemonic(), |
| 201 | GetData(node)->unscheduled_count_); |
| 202 | } |
| 203 | } |
| 204 | |
| 205 | void Scheduler::DecrementUnscheduledUseCount(Node* node, Node* from) { |
| 206 | // Tracking use counts for fixed nodes is useless. |
| 207 | if (GetPlacement(node) == kFixed) return; |
| 208 | |
| 209 | // Use count for coupled nodes is summed up on their control. |
| 210 | if (GetPlacement(node) == kCoupled) { |
| 211 | node = NodeProperties::GetControlInput(node); |
| 212 | DCHECK_NE(GetPlacement(node), Placement::kFixed)((void) 0); |
| 213 | DCHECK_NE(GetPlacement(node), Placement::kCoupled)((void) 0); |
| 214 | } |
| 215 | |
| 216 | DCHECK_LT(0, GetData(node)->unscheduled_count_)((void) 0); |
| 217 | --(GetData(node)->unscheduled_count_); |
| 218 | if (FLAG_trace_turbo_scheduler) { |
| 219 | TRACE(" Use count of #%d:%s (used by #%d:%s)-- = %d\n", node->id(), |
| 220 | node->op()->mnemonic(), from->id(), from->op()->mnemonic(), |
| 221 | GetData(node)->unscheduled_count_); |
| 222 | } |
| 223 | if (GetData(node)->unscheduled_count_ == 0) { |
| 224 | TRACE(" newly eligible #%d:%s\n", node->id(), node->op()->mnemonic()); |
| 225 | schedule_queue_.push(node); |
| 226 | } |
| 227 | } |
| 228 | |
| 229 | // ----------------------------------------------------------------------------- |
| 230 | // Phase 1: Build control-flow graph. |
| 231 | |
| 232 | |
| 233 | // Internal class to build a control flow graph (i.e the basic blocks and edges |
| 234 | // between them within a Schedule) from the node graph. Visits control edges of |
| 235 | // the graph backwards from an end node in order to find the connected control |
| 236 | // subgraph, needed for scheduling. |
| 237 | class CFGBuilder : public ZoneObject { |
| 238 | public: |
| 239 | CFGBuilder(Zone* zone, Scheduler* scheduler) |
| 240 | : zone_(zone), |
| 241 | scheduler_(scheduler), |
| 242 | schedule_(scheduler->schedule_), |
| 243 | queued_(scheduler->graph_, 2), |
| 244 | queue_(zone), |
| 245 | control_(zone), |
| 246 | component_entry_(nullptr), |
| 247 | component_start_(nullptr), |
| 248 | component_end_(nullptr) {} |
| 249 | |
| 250 | // Run the control flow graph construction algorithm by walking the graph |
| 251 | // backwards from end through control edges, building and connecting the |
| 252 | // basic blocks for control nodes. |
| 253 | void Run() { |
| 254 | ResetDataStructures(); |
| 255 | Queue(scheduler_->graph_->end()); |
| 256 | |
| 257 | while (!queue_.empty()) { // Breadth-first backwards traversal. |
| 258 | scheduler_->tick_counter_->TickAndMaybeEnterSafepoint(); |
| 259 | Node* node = queue_.front(); |
| 260 | queue_.pop(); |
| 261 | int max = NodeProperties::PastControlIndex(node); |
| 262 | for (int i = NodeProperties::FirstControlIndex(node); i < max; i++) { |
| 263 | Queue(node->InputAt(i)); |
| 264 | } |
| 265 | } |
| 266 | |
| 267 | for (NodeVector::iterator i = control_.begin(); i != control_.end(); ++i) { |
| 268 | ConnectBlocks(*i); // Connect block to its predecessor/successors. |
| 269 | } |
| 270 | } |
| 271 | |
| 272 | // Run the control flow graph construction for a minimal control-connected |
| 273 | // component ending in {exit} and merge that component into an existing |
| 274 | // control flow graph at the bottom of {block}. |
| 275 | void Run(BasicBlock* block, Node* exit) { |
| 276 | ResetDataStructures(); |
| 277 | Queue(exit); |
| 278 | |
| 279 | component_entry_ = nullptr; |
| 280 | component_start_ = block; |
| 281 | component_end_ = schedule_->block(exit); |
| 282 | scheduler_->equivalence_->Run(exit); |
| 283 | while (!queue_.empty()) { // Breadth-first backwards traversal. |
| 284 | scheduler_->tick_counter_->TickAndMaybeEnterSafepoint(); |
| 285 | Node* node = queue_.front(); |
| 286 | queue_.pop(); |
| 287 | |
| 288 | // Use control dependence equivalence to find a canonical single-entry |
| 289 | // single-exit region that makes up a minimal component to be scheduled. |
| 290 | if (IsSingleEntrySingleExitRegion(node, exit)) { |
| 291 | TRACE("Found SESE at #%d:%s\n", node->id(), node->op()->mnemonic()); |
| 292 | DCHECK(!component_entry_)((void) 0); |
| 293 | component_entry_ = node; |
| 294 | continue; |
| 295 | } |
| 296 | |
| 297 | int max = NodeProperties::PastControlIndex(node); |
| 298 | for (int i = NodeProperties::FirstControlIndex(node); i < max; i++) { |
| 299 | Queue(node->InputAt(i)); |
| 300 | } |
| 301 | } |
| 302 | DCHECK(component_entry_)((void) 0); |
| 303 | |
| 304 | for (NodeVector::iterator i = control_.begin(); i != control_.end(); ++i) { |
| 305 | ConnectBlocks(*i); // Connect block to its predecessor/successors. |
| 306 | } |
| 307 | } |
| 308 | |
| 309 | private: |
| 310 | friend class ScheduleLateNodeVisitor; |
| 311 | friend class Scheduler; |
| 312 | |
| 313 | void FixNode(BasicBlock* block, Node* node) { |
| 314 | schedule_->AddNode(block, node); |
| 315 | scheduler_->UpdatePlacement(node, Scheduler::kFixed); |
| 316 | } |
| 317 | |
| 318 | void Queue(Node* node) { |
| 319 | // Mark the connected control nodes as they are queued. |
| 320 | if (!queued_.Get(node)) { |
| 321 | BuildBlocks(node); |
| 322 | queue_.push(node); |
| 323 | queued_.Set(node, true); |
| 324 | control_.push_back(node); |
| 325 | } |
| 326 | } |
| 327 | |
| 328 | void BuildBlocks(Node* node) { |
| 329 | switch (node->opcode()) { |
| 330 | case IrOpcode::kEnd: |
| 331 | FixNode(schedule_->end(), node); |
| 332 | break; |
| 333 | case IrOpcode::kStart: |
| 334 | FixNode(schedule_->start(), node); |
| 335 | break; |
| 336 | case IrOpcode::kLoop: |
| 337 | case IrOpcode::kMerge: |
| 338 | BuildBlockForNode(node); |
| 339 | break; |
| 340 | case IrOpcode::kTerminate: { |
| 341 | // Put Terminate in the loop to which it refers. |
| 342 | Node* loop = NodeProperties::GetControlInput(node); |
| 343 | BasicBlock* block = BuildBlockForNode(loop); |
| 344 | FixNode(block, node); |
| 345 | break; |
| 346 | } |
| 347 | case IrOpcode::kBranch: |
| 348 | case IrOpcode::kSwitch: |
| 349 | BuildBlocksForSuccessors(node); |
| 350 | break; |
| 351 | #define BUILD_BLOCK_JS_CASE(Name, ...) case IrOpcode::k##Name: |
| 352 | JS_OP_LIST(BUILD_BLOCK_JS_CASE)BUILD_BLOCK_JS_CASE(JSEqual, Equal) BUILD_BLOCK_JS_CASE(JSStrictEqual , StrictEqual) BUILD_BLOCK_JS_CASE(JSLessThan, LessThan) BUILD_BLOCK_JS_CASE (JSGreaterThan, GreaterThan) BUILD_BLOCK_JS_CASE(JSLessThanOrEqual , LessThanOrEqual) BUILD_BLOCK_JS_CASE(JSGreaterThanOrEqual, GreaterThanOrEqual ) BUILD_BLOCK_JS_CASE(JSBitwiseOr, BitwiseOr) BUILD_BLOCK_JS_CASE (JSBitwiseXor, BitwiseXor) BUILD_BLOCK_JS_CASE(JSBitwiseAnd, BitwiseAnd ) BUILD_BLOCK_JS_CASE(JSShiftLeft, ShiftLeft) BUILD_BLOCK_JS_CASE (JSShiftRight, ShiftRight) BUILD_BLOCK_JS_CASE(JSShiftRightLogical , ShiftRightLogical) BUILD_BLOCK_JS_CASE(JSAdd, Add) BUILD_BLOCK_JS_CASE (JSSubtract, Subtract) BUILD_BLOCK_JS_CASE(JSMultiply, Multiply ) BUILD_BLOCK_JS_CASE(JSDivide, Divide) BUILD_BLOCK_JS_CASE(JSModulus , Modulus) BUILD_BLOCK_JS_CASE(JSExponentiate, Exponentiate) BUILD_BLOCK_JS_CASE (JSHasInPrototypeChain) BUILD_BLOCK_JS_CASE(JSInstanceOf) BUILD_BLOCK_JS_CASE (JSOrdinaryHasInstance) BUILD_BLOCK_JS_CASE(JSDecrement, Decrement ) BUILD_BLOCK_JS_CASE(JSIncrement, Increment) BUILD_BLOCK_JS_CASE (JSBitwiseNot, BitwiseNot) BUILD_BLOCK_JS_CASE(JSNegate, Negate ) BUILD_BLOCK_JS_CASE(JSToLength) BUILD_BLOCK_JS_CASE(JSToName ) BUILD_BLOCK_JS_CASE(JSToNumber) BUILD_BLOCK_JS_CASE(JSToNumberConvertBigInt ) BUILD_BLOCK_JS_CASE(JSToNumeric) BUILD_BLOCK_JS_CASE(JSToObject ) BUILD_BLOCK_JS_CASE(JSToString) BUILD_BLOCK_JS_CASE(JSParseInt ) BUILD_BLOCK_JS_CASE(JSCloneObject) BUILD_BLOCK_JS_CASE(JSCreate ) BUILD_BLOCK_JS_CASE(JSCreateArguments) BUILD_BLOCK_JS_CASE( JSCreateArray) BUILD_BLOCK_JS_CASE(JSCreateArrayFromIterable) BUILD_BLOCK_JS_CASE(JSCreateArrayIterator) BUILD_BLOCK_JS_CASE (JSCreateAsyncFunctionObject) BUILD_BLOCK_JS_CASE(JSCreateBoundFunction ) BUILD_BLOCK_JS_CASE(JSCreateClosure) BUILD_BLOCK_JS_CASE(JSCreateCollectionIterator ) BUILD_BLOCK_JS_CASE(JSCreateEmptyLiteralArray) BUILD_BLOCK_JS_CASE (JSCreateEmptyLiteralObject) BUILD_BLOCK_JS_CASE(JSCreateGeneratorObject ) BUILD_BLOCK_JS_CASE(JSCreateIterResultObject) BUILD_BLOCK_JS_CASE (JSCreateKeyValueArray) BUILD_BLOCK_JS_CASE(JSCreateLiteralArray ) BUILD_BLOCK_JS_CASE(JSCreateLiteralObject) BUILD_BLOCK_JS_CASE (JSCreateLiteralRegExp) BUILD_BLOCK_JS_CASE(JSCreateObject) BUILD_BLOCK_JS_CASE (JSCreatePromise) BUILD_BLOCK_JS_CASE(JSCreateStringIterator) BUILD_BLOCK_JS_CASE(JSCreateTypedArray) BUILD_BLOCK_JS_CASE( JSGetTemplateObject) BUILD_BLOCK_JS_CASE(JSLoadProperty) BUILD_BLOCK_JS_CASE (JSLoadNamed) BUILD_BLOCK_JS_CASE(JSLoadNamedFromSuper) BUILD_BLOCK_JS_CASE (JSLoadGlobal) BUILD_BLOCK_JS_CASE(JSSetKeyedProperty) BUILD_BLOCK_JS_CASE (JSDefineKeyedOwnProperty) BUILD_BLOCK_JS_CASE(JSSetNamedProperty ) BUILD_BLOCK_JS_CASE(JSDefineNamedOwnProperty) BUILD_BLOCK_JS_CASE (JSStoreGlobal) BUILD_BLOCK_JS_CASE(JSDefineKeyedOwnPropertyInLiteral ) BUILD_BLOCK_JS_CASE(JSStoreInArrayLiteral) BUILD_BLOCK_JS_CASE (JSDeleteProperty) BUILD_BLOCK_JS_CASE(JSHasProperty) BUILD_BLOCK_JS_CASE (JSGetSuperConstructor) BUILD_BLOCK_JS_CASE(JSHasContextExtension ) BUILD_BLOCK_JS_CASE(JSLoadContext) BUILD_BLOCK_JS_CASE(JSStoreContext ) BUILD_BLOCK_JS_CASE(JSCreateFunctionContext) BUILD_BLOCK_JS_CASE (JSCreateCatchContext) BUILD_BLOCK_JS_CASE(JSCreateWithContext ) BUILD_BLOCK_JS_CASE(JSCreateBlockContext) BUILD_BLOCK_JS_CASE (JSCall) BUILD_BLOCK_JS_CASE(JSCallForwardVarargs) BUILD_BLOCK_JS_CASE (JSCallWithArrayLike) BUILD_BLOCK_JS_CASE(JSCallWithSpread) BUILD_BLOCK_JS_CASE (JSWasmCall) BUILD_BLOCK_JS_CASE(JSConstructForwardVarargs) BUILD_BLOCK_JS_CASE (JSConstruct) BUILD_BLOCK_JS_CASE(JSConstructWithArrayLike) BUILD_BLOCK_JS_CASE (JSConstructWithSpread) BUILD_BLOCK_JS_CASE(JSAsyncFunctionEnter ) BUILD_BLOCK_JS_CASE(JSAsyncFunctionReject) BUILD_BLOCK_JS_CASE (JSAsyncFunctionResolve) BUILD_BLOCK_JS_CASE(JSCallRuntime) BUILD_BLOCK_JS_CASE (JSForInEnumerate) BUILD_BLOCK_JS_CASE(JSForInNext) BUILD_BLOCK_JS_CASE (JSForInPrepare) BUILD_BLOCK_JS_CASE(JSGetIterator) BUILD_BLOCK_JS_CASE (JSLoadMessage) BUILD_BLOCK_JS_CASE(JSStoreMessage) BUILD_BLOCK_JS_CASE (JSLoadModule) BUILD_BLOCK_JS_CASE(JSStoreModule) BUILD_BLOCK_JS_CASE (JSGetImportMeta) BUILD_BLOCK_JS_CASE(JSGeneratorStore) BUILD_BLOCK_JS_CASE (JSGeneratorRestoreContinuation) BUILD_BLOCK_JS_CASE(JSGeneratorRestoreContext ) BUILD_BLOCK_JS_CASE(JSGeneratorRestoreRegister) BUILD_BLOCK_JS_CASE (JSGeneratorRestoreInputOrDebugPos) BUILD_BLOCK_JS_CASE(JSFulfillPromise ) BUILD_BLOCK_JS_CASE(JSPerformPromiseThen) BUILD_BLOCK_JS_CASE (JSPromiseResolve) BUILD_BLOCK_JS_CASE(JSRejectPromise) BUILD_BLOCK_JS_CASE (JSResolvePromise) BUILD_BLOCK_JS_CASE(JSStackCheck) BUILD_BLOCK_JS_CASE (JSObjectIsArray) BUILD_BLOCK_JS_CASE(JSRegExpTest) BUILD_BLOCK_JS_CASE (JSDebugger) |
| 353 | // JS opcodes are just like calls => fall through. |
| 354 | #undef BUILD_BLOCK_JS_CASE |
| 355 | case IrOpcode::kCall: |
| 356 | if (NodeProperties::IsExceptionalCall(node)) { |
| 357 | BuildBlocksForSuccessors(node); |
| 358 | } |
| 359 | break; |
| 360 | default: |
| 361 | break; |
| 362 | } |
| 363 | } |
| 364 | |
| 365 | void ConnectBlocks(Node* node) { |
| 366 | switch (node->opcode()) { |
| 367 | case IrOpcode::kLoop: |
| 368 | case IrOpcode::kMerge: |
| 369 | ConnectMerge(node); |
| 370 | break; |
| 371 | case IrOpcode::kBranch: |
| 372 | scheduler_->UpdatePlacement(node, Scheduler::kFixed); |
| 373 | ConnectBranch(node); |
| 374 | break; |
| 375 | case IrOpcode::kSwitch: |
| 376 | scheduler_->UpdatePlacement(node, Scheduler::kFixed); |
| 377 | ConnectSwitch(node); |
| 378 | break; |
| 379 | case IrOpcode::kDeoptimize: |
| 380 | scheduler_->UpdatePlacement(node, Scheduler::kFixed); |
| 381 | ConnectDeoptimize(node); |
| 382 | break; |
| 383 | case IrOpcode::kTailCall: |
| 384 | scheduler_->UpdatePlacement(node, Scheduler::kFixed); |
| 385 | ConnectTailCall(node); |
| 386 | break; |
| 387 | case IrOpcode::kReturn: |
| 388 | scheduler_->UpdatePlacement(node, Scheduler::kFixed); |
| 389 | ConnectReturn(node); |
| 390 | break; |
| 391 | case IrOpcode::kThrow: |
| 392 | scheduler_->UpdatePlacement(node, Scheduler::kFixed); |
| 393 | ConnectThrow(node); |
| 394 | break; |
| 395 | #define CONNECT_BLOCK_JS_CASE(Name, ...) case IrOpcode::k##Name: |
| 396 | JS_OP_LIST(CONNECT_BLOCK_JS_CASE)CONNECT_BLOCK_JS_CASE(JSEqual, Equal) CONNECT_BLOCK_JS_CASE(JSStrictEqual , StrictEqual) CONNECT_BLOCK_JS_CASE(JSLessThan, LessThan) CONNECT_BLOCK_JS_CASE (JSGreaterThan, GreaterThan) CONNECT_BLOCK_JS_CASE(JSLessThanOrEqual , LessThanOrEqual) CONNECT_BLOCK_JS_CASE(JSGreaterThanOrEqual , GreaterThanOrEqual) CONNECT_BLOCK_JS_CASE(JSBitwiseOr, BitwiseOr ) CONNECT_BLOCK_JS_CASE(JSBitwiseXor, BitwiseXor) CONNECT_BLOCK_JS_CASE (JSBitwiseAnd, BitwiseAnd) CONNECT_BLOCK_JS_CASE(JSShiftLeft, ShiftLeft) CONNECT_BLOCK_JS_CASE(JSShiftRight, ShiftRight) CONNECT_BLOCK_JS_CASE (JSShiftRightLogical, ShiftRightLogical) CONNECT_BLOCK_JS_CASE (JSAdd, Add) CONNECT_BLOCK_JS_CASE(JSSubtract, Subtract) CONNECT_BLOCK_JS_CASE (JSMultiply, Multiply) CONNECT_BLOCK_JS_CASE(JSDivide, Divide ) CONNECT_BLOCK_JS_CASE(JSModulus, Modulus) CONNECT_BLOCK_JS_CASE (JSExponentiate, Exponentiate) CONNECT_BLOCK_JS_CASE(JSHasInPrototypeChain ) CONNECT_BLOCK_JS_CASE(JSInstanceOf) CONNECT_BLOCK_JS_CASE(JSOrdinaryHasInstance ) CONNECT_BLOCK_JS_CASE(JSDecrement, Decrement) CONNECT_BLOCK_JS_CASE (JSIncrement, Increment) CONNECT_BLOCK_JS_CASE(JSBitwiseNot, BitwiseNot ) CONNECT_BLOCK_JS_CASE(JSNegate, Negate) CONNECT_BLOCK_JS_CASE (JSToLength) CONNECT_BLOCK_JS_CASE(JSToName) CONNECT_BLOCK_JS_CASE (JSToNumber) CONNECT_BLOCK_JS_CASE(JSToNumberConvertBigInt) CONNECT_BLOCK_JS_CASE (JSToNumeric) CONNECT_BLOCK_JS_CASE(JSToObject) CONNECT_BLOCK_JS_CASE (JSToString) CONNECT_BLOCK_JS_CASE(JSParseInt) CONNECT_BLOCK_JS_CASE (JSCloneObject) CONNECT_BLOCK_JS_CASE(JSCreate) CONNECT_BLOCK_JS_CASE (JSCreateArguments) CONNECT_BLOCK_JS_CASE(JSCreateArray) CONNECT_BLOCK_JS_CASE (JSCreateArrayFromIterable) CONNECT_BLOCK_JS_CASE(JSCreateArrayIterator ) CONNECT_BLOCK_JS_CASE(JSCreateAsyncFunctionObject) CONNECT_BLOCK_JS_CASE (JSCreateBoundFunction) CONNECT_BLOCK_JS_CASE(JSCreateClosure ) CONNECT_BLOCK_JS_CASE(JSCreateCollectionIterator) CONNECT_BLOCK_JS_CASE (JSCreateEmptyLiteralArray) CONNECT_BLOCK_JS_CASE(JSCreateEmptyLiteralObject ) CONNECT_BLOCK_JS_CASE(JSCreateGeneratorObject) CONNECT_BLOCK_JS_CASE (JSCreateIterResultObject) CONNECT_BLOCK_JS_CASE(JSCreateKeyValueArray ) CONNECT_BLOCK_JS_CASE(JSCreateLiteralArray) CONNECT_BLOCK_JS_CASE (JSCreateLiteralObject) CONNECT_BLOCK_JS_CASE(JSCreateLiteralRegExp ) CONNECT_BLOCK_JS_CASE(JSCreateObject) CONNECT_BLOCK_JS_CASE (JSCreatePromise) CONNECT_BLOCK_JS_CASE(JSCreateStringIterator ) CONNECT_BLOCK_JS_CASE(JSCreateTypedArray) CONNECT_BLOCK_JS_CASE (JSGetTemplateObject) CONNECT_BLOCK_JS_CASE(JSLoadProperty) CONNECT_BLOCK_JS_CASE (JSLoadNamed) CONNECT_BLOCK_JS_CASE(JSLoadNamedFromSuper) CONNECT_BLOCK_JS_CASE (JSLoadGlobal) CONNECT_BLOCK_JS_CASE(JSSetKeyedProperty) CONNECT_BLOCK_JS_CASE (JSDefineKeyedOwnProperty) CONNECT_BLOCK_JS_CASE(JSSetNamedProperty ) CONNECT_BLOCK_JS_CASE(JSDefineNamedOwnProperty) CONNECT_BLOCK_JS_CASE (JSStoreGlobal) CONNECT_BLOCK_JS_CASE(JSDefineKeyedOwnPropertyInLiteral ) CONNECT_BLOCK_JS_CASE(JSStoreInArrayLiteral) CONNECT_BLOCK_JS_CASE (JSDeleteProperty) CONNECT_BLOCK_JS_CASE(JSHasProperty) CONNECT_BLOCK_JS_CASE (JSGetSuperConstructor) CONNECT_BLOCK_JS_CASE(JSHasContextExtension ) CONNECT_BLOCK_JS_CASE(JSLoadContext) CONNECT_BLOCK_JS_CASE( JSStoreContext) CONNECT_BLOCK_JS_CASE(JSCreateFunctionContext ) CONNECT_BLOCK_JS_CASE(JSCreateCatchContext) CONNECT_BLOCK_JS_CASE (JSCreateWithContext) CONNECT_BLOCK_JS_CASE(JSCreateBlockContext ) CONNECT_BLOCK_JS_CASE(JSCall) CONNECT_BLOCK_JS_CASE(JSCallForwardVarargs ) CONNECT_BLOCK_JS_CASE(JSCallWithArrayLike) CONNECT_BLOCK_JS_CASE (JSCallWithSpread) CONNECT_BLOCK_JS_CASE(JSWasmCall) CONNECT_BLOCK_JS_CASE (JSConstructForwardVarargs) CONNECT_BLOCK_JS_CASE(JSConstruct ) CONNECT_BLOCK_JS_CASE(JSConstructWithArrayLike) CONNECT_BLOCK_JS_CASE (JSConstructWithSpread) CONNECT_BLOCK_JS_CASE(JSAsyncFunctionEnter ) CONNECT_BLOCK_JS_CASE(JSAsyncFunctionReject) CONNECT_BLOCK_JS_CASE (JSAsyncFunctionResolve) CONNECT_BLOCK_JS_CASE(JSCallRuntime) CONNECT_BLOCK_JS_CASE(JSForInEnumerate) CONNECT_BLOCK_JS_CASE (JSForInNext) CONNECT_BLOCK_JS_CASE(JSForInPrepare) CONNECT_BLOCK_JS_CASE (JSGetIterator) CONNECT_BLOCK_JS_CASE(JSLoadMessage) CONNECT_BLOCK_JS_CASE (JSStoreMessage) CONNECT_BLOCK_JS_CASE(JSLoadModule) CONNECT_BLOCK_JS_CASE (JSStoreModule) CONNECT_BLOCK_JS_CASE(JSGetImportMeta) CONNECT_BLOCK_JS_CASE (JSGeneratorStore) CONNECT_BLOCK_JS_CASE(JSGeneratorRestoreContinuation ) CONNECT_BLOCK_JS_CASE(JSGeneratorRestoreContext) CONNECT_BLOCK_JS_CASE (JSGeneratorRestoreRegister) CONNECT_BLOCK_JS_CASE(JSGeneratorRestoreInputOrDebugPos ) CONNECT_BLOCK_JS_CASE(JSFulfillPromise) CONNECT_BLOCK_JS_CASE (JSPerformPromiseThen) CONNECT_BLOCK_JS_CASE(JSPromiseResolve ) CONNECT_BLOCK_JS_CASE(JSRejectPromise) CONNECT_BLOCK_JS_CASE (JSResolvePromise) CONNECT_BLOCK_JS_CASE(JSStackCheck) CONNECT_BLOCK_JS_CASE (JSObjectIsArray) CONNECT_BLOCK_JS_CASE(JSRegExpTest) CONNECT_BLOCK_JS_CASE (JSDebugger) |
| 397 | // JS opcodes are just like calls => fall through. |
| 398 | #undef CONNECT_BLOCK_JS_CASE |
| 399 | case IrOpcode::kCall: |
| 400 | if (NodeProperties::IsExceptionalCall(node)) { |
| 401 | scheduler_->UpdatePlacement(node, Scheduler::kFixed); |
| 402 | ConnectCall(node); |
| 403 | } |
| 404 | break; |
| 405 | default: |
| 406 | break; |
| 407 | } |
| 408 | } |
| 409 | |
| 410 | BasicBlock* BuildBlockForNode(Node* node) { |
| 411 | BasicBlock* block = schedule_->block(node); |
| 412 | if (block == nullptr) { |
| 413 | block = schedule_->NewBasicBlock(); |
| 414 | TRACE("Create block id:%d for #%d:%s\n", block->id().ToInt(), node->id(), |
| 415 | node->op()->mnemonic()); |
| 416 | FixNode(block, node); |
| 417 | } |
| 418 | return block; |
| 419 | } |
| 420 | |
| 421 | void BuildBlocksForSuccessors(Node* node) { |
| 422 | size_t const successor_cnt = node->op()->ControlOutputCount(); |
| 423 | Node** successors = zone_->NewArray<Node*>(successor_cnt); |
| 424 | NodeProperties::CollectControlProjections(node, successors, successor_cnt); |
| 425 | for (size_t index = 0; index < successor_cnt; ++index) { |
| 426 | BuildBlockForNode(successors[index]); |
| 427 | } |
| 428 | } |
| 429 | |
| 430 | void CollectSuccessorBlocks(Node* node, BasicBlock** successor_blocks, |
| 431 | size_t successor_cnt) { |
| 432 | Node** successors = reinterpret_cast<Node**>(successor_blocks); |
| 433 | NodeProperties::CollectControlProjections(node, successors, successor_cnt); |
| 434 | for (size_t index = 0; index < successor_cnt; ++index) { |
| 435 | successor_blocks[index] = schedule_->block(successors[index]); |
| 436 | } |
| 437 | } |
| 438 | |
| 439 | BasicBlock* FindPredecessorBlock(Node* node) { |
| 440 | BasicBlock* predecessor_block = nullptr; |
| 441 | while (true) { |
| 442 | predecessor_block = schedule_->block(node); |
| 443 | if (predecessor_block != nullptr) break; |
| 444 | node = NodeProperties::GetControlInput(node); |
| 445 | } |
| 446 | return predecessor_block; |
| 447 | } |
| 448 | |
| 449 | void ConnectCall(Node* call) { |
| 450 | BasicBlock* successor_blocks[2]; |
| 451 | CollectSuccessorBlocks(call, successor_blocks, arraysize(successor_blocks)(sizeof(ArraySizeHelper(successor_blocks)))); |
| 452 | |
| 453 | // Consider the exception continuation to be deferred. |
| 454 | successor_blocks[1]->set_deferred(true); |
| 455 | |
| 456 | Node* call_control = NodeProperties::GetControlInput(call); |
| 457 | BasicBlock* call_block = FindPredecessorBlock(call_control); |
| 458 | TraceConnect(call, call_block, successor_blocks[0]); |
| 459 | TraceConnect(call, call_block, successor_blocks[1]); |
| 460 | schedule_->AddCall(call_block, call, successor_blocks[0], |
| 461 | successor_blocks[1]); |
| 462 | } |
| 463 | |
| 464 | void ConnectBranch(Node* branch) { |
| 465 | BasicBlock* successor_blocks[2]; |
| 466 | CollectSuccessorBlocks(branch, successor_blocks, |
| 467 | arraysize(successor_blocks)(sizeof(ArraySizeHelper(successor_blocks)))); |
| 468 | |
| 469 | BranchHint hint_from_profile = BranchHint::kNone; |
| 470 | if (const ProfileDataFromFile* profile_data = scheduler_->profile_data()) { |
| 471 | double block_zero_count = |
| 472 | profile_data->GetCounter(successor_blocks[0]->id().ToSize()); |
| 473 | double block_one_count = |
| 474 | profile_data->GetCounter(successor_blocks[1]->id().ToSize()); |
| 475 | // If a branch is visited a non-trivial number of times and substantially |
| 476 | // more often than its alternative, then mark it as likely. |
| 477 | constexpr double kMinimumCount = 100000; |
| 478 | constexpr double kThresholdRatio = 4000; |
| 479 | if (block_zero_count > kMinimumCount && |
| 480 | block_zero_count / kThresholdRatio > block_one_count) { |
| 481 | hint_from_profile = BranchHint::kTrue; |
| 482 | } else if (block_one_count > kMinimumCount && |
| 483 | block_one_count / kThresholdRatio > block_zero_count) { |
| 484 | hint_from_profile = BranchHint::kFalse; |
| 485 | } |
| 486 | } |
| 487 | |
| 488 | // Consider branch hints. |
| 489 | switch (hint_from_profile) { |
| 490 | case BranchHint::kNone: |
| 491 | switch (BranchHintOf(branch->op())) { |
| 492 | case BranchHint::kNone: |
| 493 | break; |
| 494 | case BranchHint::kTrue: |
| 495 | successor_blocks[1]->set_deferred(true); |
| 496 | break; |
| 497 | case BranchHint::kFalse: |
| 498 | successor_blocks[0]->set_deferred(true); |
| 499 | break; |
| 500 | } |
| 501 | break; |
| 502 | case BranchHint::kTrue: |
| 503 | successor_blocks[1]->set_deferred(true); |
| 504 | break; |
| 505 | case BranchHint::kFalse: |
| 506 | successor_blocks[0]->set_deferred(true); |
| 507 | break; |
| 508 | } |
| 509 | |
| 510 | if (hint_from_profile != BranchHint::kNone && |
| 511 | BranchHintOf(branch->op()) != BranchHint::kNone && |
| 512 | hint_from_profile != BranchHintOf(branch->op())) { |
| 513 | PrintF("Warning: profiling data overrode manual branch hint.\n"); |
| 514 | } |
| 515 | |
| 516 | if (branch == component_entry_) { |
| 517 | TraceConnect(branch, component_start_, successor_blocks[0]); |
| 518 | TraceConnect(branch, component_start_, successor_blocks[1]); |
| 519 | schedule_->InsertBranch(component_start_, component_end_, branch, |
| 520 | successor_blocks[0], successor_blocks[1]); |
| 521 | } else { |
| 522 | Node* branch_control = NodeProperties::GetControlInput(branch); |
| 523 | BasicBlock* branch_block = FindPredecessorBlock(branch_control); |
| 524 | TraceConnect(branch, branch_block, successor_blocks[0]); |
| 525 | TraceConnect(branch, branch_block, successor_blocks[1]); |
| 526 | schedule_->AddBranch(branch_block, branch, successor_blocks[0], |
| 527 | successor_blocks[1]); |
| 528 | } |
| 529 | } |
| 530 | |
| 531 | void ConnectSwitch(Node* sw) { |
| 532 | size_t const successor_count = sw->op()->ControlOutputCount(); |
| 533 | BasicBlock** successor_blocks = |
| 534 | zone_->NewArray<BasicBlock*>(successor_count); |
| 535 | CollectSuccessorBlocks(sw, successor_blocks, successor_count); |
| 536 | |
| 537 | if (sw == component_entry_) { |
| 538 | for (size_t index = 0; index < successor_count; ++index) { |
| 539 | TraceConnect(sw, component_start_, successor_blocks[index]); |
| 540 | } |
| 541 | schedule_->InsertSwitch(component_start_, component_end_, sw, |
| 542 | successor_blocks, successor_count); |
| 543 | } else { |
| 544 | Node* switch_control = NodeProperties::GetControlInput(sw); |
| 545 | BasicBlock* switch_block = FindPredecessorBlock(switch_control); |
| 546 | for (size_t index = 0; index < successor_count; ++index) { |
| 547 | TraceConnect(sw, switch_block, successor_blocks[index]); |
| 548 | } |
| 549 | schedule_->AddSwitch(switch_block, sw, successor_blocks, successor_count); |
| 550 | } |
| 551 | for (size_t index = 0; index < successor_count; ++index) { |
| 552 | if (BranchHintOf(successor_blocks[index]->front()->op()) == |
| 553 | BranchHint::kFalse) { |
| 554 | successor_blocks[index]->set_deferred(true); |
| 555 | } |
| 556 | } |
| 557 | } |
| 558 | |
| 559 | void ConnectMerge(Node* merge) { |
| 560 | // Don't connect the special merge at the end to its predecessors. |
| 561 | if (IsFinalMerge(merge)) return; |
| 562 | |
| 563 | BasicBlock* block = schedule_->block(merge); |
| 564 | DCHECK_NOT_NULL(block)((void) 0); |
| 565 | // For all of the merge's control inputs, add a goto at the end to the |
| 566 | // merge's basic block. |
| 567 | for (Node* const input : merge->inputs()) { |
| 568 | BasicBlock* predecessor_block = FindPredecessorBlock(input); |
| 569 | TraceConnect(merge, predecessor_block, block); |
| 570 | schedule_->AddGoto(predecessor_block, block); |
| 571 | } |
| 572 | } |
| 573 | |
| 574 | void ConnectTailCall(Node* call) { |
| 575 | Node* call_control = NodeProperties::GetControlInput(call); |
| 576 | BasicBlock* call_block = FindPredecessorBlock(call_control); |
| 577 | TraceConnect(call, call_block, nullptr); |
| 578 | schedule_->AddTailCall(call_block, call); |
| 579 | } |
| 580 | |
| 581 | void ConnectReturn(Node* ret) { |
| 582 | Node* return_control = NodeProperties::GetControlInput(ret); |
| 583 | BasicBlock* return_block = FindPredecessorBlock(return_control); |
| 584 | TraceConnect(ret, return_block, nullptr); |
| 585 | schedule_->AddReturn(return_block, ret); |
| 586 | } |
| 587 | |
| 588 | void ConnectDeoptimize(Node* deopt) { |
| 589 | Node* deoptimize_control = NodeProperties::GetControlInput(deopt); |
| 590 | BasicBlock* deoptimize_block = FindPredecessorBlock(deoptimize_control); |
| 591 | TraceConnect(deopt, deoptimize_block, nullptr); |
| 592 | schedule_->AddDeoptimize(deoptimize_block, deopt); |
| 593 | } |
| 594 | |
| 595 | void ConnectThrow(Node* thr) { |
| 596 | Node* throw_control = NodeProperties::GetControlInput(thr); |
| 597 | BasicBlock* throw_block = FindPredecessorBlock(throw_control); |
| 598 | TraceConnect(thr, throw_block, nullptr); |
| 599 | schedule_->AddThrow(throw_block, thr); |
| 600 | } |
| 601 | |
| 602 | void TraceConnect(Node* node, BasicBlock* block, BasicBlock* succ) { |
| 603 | DCHECK_NOT_NULL(block)((void) 0); |
| 604 | if (succ == nullptr) { |
| 605 | TRACE("Connect #%d:%s, id:%d -> end\n", node->id(), |
| 606 | node->op()->mnemonic(), block->id().ToInt()); |
| 607 | } else { |
| 608 | TRACE("Connect #%d:%s, id:%d -> id:%d\n", node->id(), |
| 609 | node->op()->mnemonic(), block->id().ToInt(), succ->id().ToInt()); |
| 610 | } |
| 611 | } |
| 612 | |
| 613 | bool IsFinalMerge(Node* node) { |
| 614 | return (node->opcode() == IrOpcode::kMerge && |
| 615 | node == scheduler_->graph_->end()->InputAt(0)); |
| 616 | } |
| 617 | |
| 618 | bool IsSingleEntrySingleExitRegion(Node* entry, Node* exit) const { |
| 619 | size_t entry_class = scheduler_->equivalence_->ClassOf(entry); |
| 620 | size_t exit_class = scheduler_->equivalence_->ClassOf(exit); |
| 621 | return entry != exit && entry_class == exit_class; |
| 622 | } |
| 623 | |
| 624 | void ResetDataStructures() { |
| 625 | control_.clear(); |
| 626 | DCHECK(queue_.empty())((void) 0); |
| 627 | DCHECK(control_.empty())((void) 0); |
| 628 | } |
| 629 | |
| 630 | Zone* zone_; |
| 631 | Scheduler* scheduler_; |
| 632 | Schedule* schedule_; |
| 633 | NodeMarker<bool> queued_; // Mark indicating whether node is queued. |
| 634 | ZoneQueue<Node*> queue_; // Queue used for breadth-first traversal. |
| 635 | NodeVector control_; // List of encountered control nodes. |
| 636 | Node* component_entry_; // Component single-entry node. |
| 637 | BasicBlock* component_start_; // Component single-entry block. |
| 638 | BasicBlock* component_end_; // Component single-exit block. |
| 639 | }; |
| 640 | |
| 641 | |
| 642 | void Scheduler::BuildCFG() { |
| 643 | TRACE("--- CREATING CFG -------------------------------------------\n"); |
| 644 | |
| 645 | // Instantiate a new control equivalence algorithm for the graph. |
| 646 | equivalence_ = zone_->New<ControlEquivalence>(zone_, graph_); |
| 647 | |
| 648 | // Build a control-flow graph for the main control-connected component that |
| 649 | // is being spanned by the graph's start and end nodes. |
| 650 | control_flow_builder_ = zone_->New<CFGBuilder>(zone_, this); |
| 651 | control_flow_builder_->Run(); |
| 652 | |
| 653 | // Initialize per-block data. |
| 654 | // Reserve an extra 10% to avoid resizing vector when fusing floating control. |
| 655 | scheduled_nodes_.reserve(schedule_->BasicBlockCount() * 1.1); |
| 656 | scheduled_nodes_.resize(schedule_->BasicBlockCount()); |
| 657 | } |
| 658 | |
| 659 | |
| 660 | // ----------------------------------------------------------------------------- |
| 661 | // Phase 2: Compute special RPO and dominator tree. |
| 662 | |
| 663 | |
| 664 | // Compute the special reverse-post-order block ordering, which is essentially |
| 665 | // a RPO of the graph where loop bodies are contiguous. Properties: |
| 666 | // 1. If block A is a predecessor of B, then A appears before B in the order, |
| 667 | // unless B is a loop header and A is in the loop headed at B |
| 668 | // (i.e. A -> B is a backedge). |
| 669 | // => If block A dominates block B, then A appears before B in the order. |
| 670 | // => If block A is a loop header, A appears before all blocks in the loop |
| 671 | // headed at A. |
| 672 | // 2. All loops are contiguous in the order (i.e. no intervening blocks that |
| 673 | // do not belong to the loop.) |
| 674 | // Note a simple RPO traversal satisfies (1) but not (2). |
| 675 | class SpecialRPONumberer : public ZoneObject { |
| 676 | public: |
| 677 | SpecialRPONumberer(Zone* zone, Schedule* schedule) |
| 678 | : zone_(zone), |
| 679 | schedule_(schedule), |
| 680 | order_(nullptr), |
| 681 | beyond_end_(nullptr), |
| 682 | loops_(zone), |
| 683 | backedges_(zone), |
| 684 | stack_(zone), |
| 685 | previous_block_count_(0), |
| 686 | empty_(0, zone) {} |
| 687 | |
| 688 | // Computes the special reverse-post-order for the main control flow graph, |
| 689 | // that is for the graph spanned between the schedule's start and end blocks. |
| 690 | void ComputeSpecialRPO() { |
| 691 | DCHECK_EQ(0, schedule_->end()->SuccessorCount())((void) 0); |
| 692 | DCHECK(!order_)((void) 0); // Main order does not exist yet. |
| 693 | ComputeAndInsertSpecialRPO(schedule_->start(), schedule_->end()); |
| 694 | } |
| 695 | |
| 696 | // Computes the special reverse-post-order for a partial control flow graph, |
| 697 | // that is for the graph spanned between the given {entry} and {end} blocks, |
| 698 | // then updates the existing ordering with this new information. |
| 699 | void UpdateSpecialRPO(BasicBlock* entry, BasicBlock* end) { |
| 700 | DCHECK(order_)((void) 0); // Main order to be updated is present. |
| 701 | ComputeAndInsertSpecialRPO(entry, end); |
| 702 | } |
| 703 | |
| 704 | // Serialize the previously computed order as a special reverse-post-order |
| 705 | // numbering for basic blocks into the final schedule. |
| 706 | void SerializeRPOIntoSchedule() { |
| 707 | int32_t number = 0; |
| 708 | for (BasicBlock* b = order_; b != nullptr; b = b->rpo_next()) { |
| 709 | b->set_rpo_number(number++); |
| 710 | schedule_->rpo_order()->push_back(b); |
| 711 | } |
| 712 | BeyondEndSentinel()->set_rpo_number(number); |
| 713 | } |
| 714 | |
| 715 | // Print and verify the special reverse-post-order. |
| 716 | void PrintAndVerifySpecialRPO() { |
| 717 | #if DEBUG |
| 718 | if (FLAG_trace_turbo_scheduler) PrintRPO(); |
| 719 | VerifySpecialRPO(); |
| 720 | #endif |
| 721 | } |
| 722 | |
| 723 | const ZoneVector<BasicBlock*>& GetOutgoingBlocks(BasicBlock* block) { |
| 724 | if (HasLoopNumber(block)) { |
| 725 | LoopInfo const& loop = loops_[GetLoopNumber(block)]; |
| 726 | if (loop.outgoing) return *loop.outgoing; |
| 727 | } |
| 728 | return empty_; |
| 729 | } |
| 730 | |
| 731 | bool HasLoopBlocks() const { return loops_.size() != 0; } |
| 732 | |
| 733 | private: |
| 734 | using Backedge = std::pair<BasicBlock*, size_t>; |
| 735 | |
| 736 | // Numbering for BasicBlock::rpo_number for this block traversal: |
| 737 | static const int kBlockOnStack = -2; |
| 738 | static const int kBlockVisited1 = -3; |
| 739 | static const int kBlockVisited2 = -4; |
| 740 | static const int kBlockUnvisited1 = -1; |
| 741 | static const int kBlockUnvisited2 = kBlockVisited1; |
| 742 | |
| 743 | struct SpecialRPOStackFrame { |
| 744 | BasicBlock* block; |
| 745 | size_t index; |
| 746 | }; |
| 747 | |
| 748 | struct LoopInfo { |
| 749 | BasicBlock* header; |
| 750 | ZoneVector<BasicBlock*>* outgoing; |
| 751 | BitVector* members; |
| 752 | LoopInfo* prev; |
| 753 | BasicBlock* end; |
| 754 | BasicBlock* start; |
| 755 | |
| 756 | void AddOutgoing(Zone* zone, BasicBlock* block) { |
| 757 | if (outgoing == nullptr) { |
| 758 | outgoing = zone->New<ZoneVector<BasicBlock*>>(zone); |
| 759 | } |
| 760 | outgoing->push_back(block); |
| 761 | } |
| 762 | }; |
| 763 | |
| 764 | int Push(int depth, BasicBlock* child, int unvisited) { |
| 765 | if (child->rpo_number() == unvisited) { |
| 766 | stack_[depth].block = child; |
| 767 | stack_[depth].index = 0; |
| 768 | child->set_rpo_number(kBlockOnStack); |
| 769 | return depth + 1; |
| 770 | } |
| 771 | return depth; |
| 772 | } |
| 773 | |
| 774 | BasicBlock* PushFront(BasicBlock* head, BasicBlock* block) { |
| 775 | block->set_rpo_next(head); |
| 776 | return block; |
| 777 | } |
| 778 | |
| 779 | static int GetLoopNumber(BasicBlock* block) { return block->loop_number(); } |
| 780 | static void SetLoopNumber(BasicBlock* block, int loop_number) { |
| 781 | return block->set_loop_number(loop_number); |
| 782 | } |
| 783 | static bool HasLoopNumber(BasicBlock* block) { |
| 784 | return block->loop_number() >= 0; |
| 785 | } |
| 786 | |
| 787 | // We only need this special sentinel because some tests use the schedule's |
| 788 | // end block in actual control flow (e.g. with end having successors). |
| 789 | BasicBlock* BeyondEndSentinel() { |
| 790 | if (beyond_end_ == nullptr) { |
| 791 | BasicBlock::Id id = BasicBlock::Id::FromInt(-1); |
| 792 | beyond_end_ = schedule_->zone()->New<BasicBlock>(schedule_->zone(), id); |
| 793 | } |
| 794 | return beyond_end_; |
| 795 | } |
| 796 | |
| 797 | // Compute special RPO for the control flow graph between {entry} and {end}, |
| 798 | // mutating any existing order so that the result is still valid. |
| 799 | void ComputeAndInsertSpecialRPO(BasicBlock* entry, BasicBlock* end) { |
| 800 | // RPO should not have been serialized for this schedule yet. |
| 801 | CHECK_EQ(kBlockUnvisited1, schedule_->start()->loop_number())do { bool _cmp = ::v8::base::CmpEQImpl< typename ::v8::base ::pass_value_or_ref<decltype(kBlockUnvisited1)>::type, typename ::v8::base::pass_value_or_ref<decltype(schedule_->start ()->loop_number())>::type>((kBlockUnvisited1), (schedule_ ->start()->loop_number())); do { if ((__builtin_expect( !!(!(_cmp)), 0))) { V8_Fatal("Check failed: %s.", "kBlockUnvisited1" " " "==" " " "schedule_->start()->loop_number()"); } } while (false); } while (false); |
| 802 | CHECK_EQ(kBlockUnvisited1, schedule_->start()->rpo_number())do { bool _cmp = ::v8::base::CmpEQImpl< typename ::v8::base ::pass_value_or_ref<decltype(kBlockUnvisited1)>::type, typename ::v8::base::pass_value_or_ref<decltype(schedule_->start ()->rpo_number())>::type>((kBlockUnvisited1), (schedule_ ->start()->rpo_number())); do { if ((__builtin_expect(! !(!(_cmp)), 0))) { V8_Fatal("Check failed: %s.", "kBlockUnvisited1" " " "==" " " "schedule_->start()->rpo_number()"); } } while (false); } while (false); |
| 803 | CHECK_EQ(0, static_cast<int>(schedule_->rpo_order()->size()))do { bool _cmp = ::v8::base::CmpEQImpl< typename ::v8::base ::pass_value_or_ref<decltype(0)>::type, typename ::v8:: base::pass_value_or_ref<decltype(static_cast<int>(schedule_ ->rpo_order()->size()))>::type>((0), (static_cast <int>(schedule_->rpo_order()->size()))); do { if ( (__builtin_expect(!!(!(_cmp)), 0))) { V8_Fatal("Check failed: %s." , "0" " " "==" " " "static_cast<int>(schedule_->rpo_order()->size())" ); } } while (false); } while (false); |
| 804 | |
| 805 | // Find correct insertion point within existing order. |
| 806 | BasicBlock* insertion_point = entry->rpo_next(); |
| 807 | BasicBlock* order = insertion_point; |
| 808 | |
| 809 | // Perform an iterative RPO traversal using an explicit stack, |
| 810 | // recording backedges that form cycles. O(|B|). |
| 811 | DCHECK_LT(previous_block_count_, schedule_->BasicBlockCount())((void) 0); |
| 812 | stack_.resize(schedule_->BasicBlockCount() - previous_block_count_); |
| 813 | previous_block_count_ = schedule_->BasicBlockCount(); |
| 814 | int stack_depth = Push(0, entry, kBlockUnvisited1); |
| 815 | int num_loops = static_cast<int>(loops_.size()); |
| 816 | |
| 817 | while (stack_depth > 0) { |
| 818 | int current = stack_depth - 1; |
| 819 | SpecialRPOStackFrame* frame = &stack_[current]; |
| 820 | |
| 821 | if (frame->block != end && |
| 822 | frame->index < frame->block->SuccessorCount()) { |
| 823 | // Process the next successor. |
| 824 | BasicBlock* succ = frame->block->SuccessorAt(frame->index++); |
| 825 | if (succ->rpo_number() == kBlockVisited1) continue; |
| 826 | if (succ->rpo_number() == kBlockOnStack) { |
| 827 | // The successor is on the stack, so this is a backedge (cycle). |
| 828 | backedges_.push_back(Backedge(frame->block, frame->index - 1)); |
| 829 | if (!HasLoopNumber(succ)) { |
| 830 | // Assign a new loop number to the header if it doesn't have one. |
| 831 | SetLoopNumber(succ, num_loops++); |
| 832 | } |
| 833 | } else { |
| 834 | // Push the successor onto the stack. |
| 835 | DCHECK_EQ(kBlockUnvisited1, succ->rpo_number())((void) 0); |
| 836 | stack_depth = Push(stack_depth, succ, kBlockUnvisited1); |
| 837 | } |
| 838 | } else { |
| 839 | // Finished with all successors; pop the stack and add the block. |
| 840 | order = PushFront(order, frame->block); |
| 841 | frame->block->set_rpo_number(kBlockVisited1); |
| 842 | stack_depth--; |
| 843 | } |
| 844 | } |
| 845 | |
| 846 | // If no loops were encountered, then the order we computed was correct. |
| 847 | if (num_loops > static_cast<int>(loops_.size())) { |
| 848 | // Otherwise, compute the loop information from the backedges in order |
| 849 | // to perform a traversal that groups loop bodies together. |
| 850 | ComputeLoopInfo(&stack_, num_loops, &backedges_); |
| 851 | |
| 852 | // Initialize the "loop stack". Note the entry could be a loop header. |
| 853 | LoopInfo* loop = |
| 854 | HasLoopNumber(entry) ? &loops_[GetLoopNumber(entry)] : nullptr; |
| 855 | order = insertion_point; |
| 856 | |
| 857 | // Perform an iterative post-order traversal, visiting loop bodies before |
| 858 | // edges that lead out of loops. Visits each block once, but linking loop |
| 859 | // sections together is linear in the loop size, so overall is |
| 860 | // O(|B| + max(loop_depth) * max(|loop|)) |
| 861 | stack_depth = Push(0, entry, kBlockUnvisited2); |
| 862 | while (stack_depth > 0) { |
| 863 | SpecialRPOStackFrame* frame = &stack_[stack_depth - 1]; |
| 864 | BasicBlock* block = frame->block; |
| 865 | BasicBlock* succ = nullptr; |
| 866 | |
| 867 | if (block != end && frame->index < block->SuccessorCount()) { |
| 868 | // Process the next normal successor. |
| 869 | succ = block->SuccessorAt(frame->index++); |
| 870 | } else if (HasLoopNumber(block)) { |
| 871 | // Process additional outgoing edges from the loop header. |
| 872 | if (block->rpo_number() == kBlockOnStack) { |
| 873 | // Finish the loop body the first time the header is left on the |
| 874 | // stack. |
| 875 | DCHECK(loop != nullptr && loop->header == block)((void) 0); |
| 876 | loop->start = PushFront(order, block); |
| 877 | order = loop->end; |
| 878 | block->set_rpo_number(kBlockVisited2); |
| 879 | // Pop the loop stack and continue visiting outgoing edges within |
| 880 | // the context of the outer loop, if any. |
| 881 | loop = loop->prev; |
| 882 | // We leave the loop header on the stack; the rest of this iteration |
| 883 | // and later iterations will go through its outgoing edges list. |
| 884 | } |
| 885 | |
| 886 | // Use the next outgoing edge if there are any. |
| 887 | size_t outgoing_index = frame->index - block->SuccessorCount(); |
| 888 | LoopInfo* info = &loops_[GetLoopNumber(block)]; |
| 889 | DCHECK(loop != info)((void) 0); |
| 890 | if (block != entry && info->outgoing != nullptr && |
| 891 | outgoing_index < info->outgoing->size()) { |
| 892 | succ = info->outgoing->at(outgoing_index); |
| 893 | frame->index++; |
| 894 | } |
| 895 | } |
| 896 | |
| 897 | if (succ != nullptr) { |
| 898 | // Process the next successor. |
| 899 | if (succ->rpo_number() == kBlockOnStack) continue; |
| 900 | if (succ->rpo_number() == kBlockVisited2) continue; |
| 901 | DCHECK_EQ(kBlockUnvisited2, succ->rpo_number())((void) 0); |
| 902 | if (loop != nullptr && !loop->members->Contains(succ->id().ToInt())) { |
| 903 | // The successor is not in the current loop or any nested loop. |
| 904 | // Add it to the outgoing edges of this loop and visit it later. |
| 905 | loop->AddOutgoing(zone_, succ); |
| 906 | } else { |
| 907 | // Push the successor onto the stack. |
| 908 | stack_depth = Push(stack_depth, succ, kBlockUnvisited2); |
| 909 | if (HasLoopNumber(succ)) { |
| 910 | // Push the inner loop onto the loop stack. |
| 911 | DCHECK(GetLoopNumber(succ) < num_loops)((void) 0); |
| 912 | LoopInfo* next = &loops_[GetLoopNumber(succ)]; |
| 913 | next->end = order; |
| 914 | next->prev = loop; |
| 915 | loop = next; |
| 916 | } |
| 917 | } |
| 918 | } else { |
| 919 | // Finished with all successors of the current block. |
| 920 | if (HasLoopNumber(block)) { |
| 921 | // If we are going to pop a loop header, then add its entire body. |
| 922 | LoopInfo* info = &loops_[GetLoopNumber(block)]; |
| 923 | for (BasicBlock* b = info->start; true; b = b->rpo_next()) { |
| 924 | if (b->rpo_next() == info->end) { |
| 925 | b->set_rpo_next(order); |
| 926 | info->end = order; |
| 927 | break; |
| 928 | } |
| 929 | } |
| 930 | order = info->start; |
| 931 | } else { |
| 932 | // Pop a single node off the stack and add it to the order. |
| 933 | order = PushFront(order, block); |
| 934 | block->set_rpo_number(kBlockVisited2); |
| 935 | } |
| 936 | stack_depth--; |
| 937 | } |
| 938 | } |
| 939 | } |
| 940 | |
| 941 | // Publish new order the first time. |
| 942 | if (order_ == nullptr) order_ = order; |
| 943 | |
| 944 | // Compute the correct loop headers and set the correct loop ends. |
| 945 | LoopInfo* current_loop = nullptr; |
| 946 | BasicBlock* current_header = entry->loop_header(); |
| 947 | int32_t loop_depth = entry->loop_depth(); |
| 948 | if (entry->IsLoopHeader()) --loop_depth; // Entry might be a loop header. |
| 949 | for (BasicBlock* b = order; b != insertion_point; b = b->rpo_next()) { |
| 950 | BasicBlock* current = b; |
| 951 | |
| 952 | // Reset BasicBlock::rpo_number again. |
| 953 | current->set_rpo_number(kBlockUnvisited1); |
| 954 | |
| 955 | // Finish the previous loop(s) if we just exited them. |
| 956 | while (current_header != nullptr && |
| 957 | current == current_header->loop_end()) { |
| 958 | DCHECK(current_header->IsLoopHeader())((void) 0); |
| 959 | DCHECK_NOT_NULL(current_loop)((void) 0); |
| 960 | current_loop = current_loop->prev; |
| 961 | current_header = |
| 962 | current_loop == nullptr ? nullptr : current_loop->header; |
| 963 | --loop_depth; |
| 964 | } |
| 965 | current->set_loop_header(current_header); |
| 966 | |
| 967 | // Push a new loop onto the stack if this loop is a loop header. |
| 968 | if (HasLoopNumber(current)) { |
| 969 | ++loop_depth; |
| 970 | current_loop = &loops_[GetLoopNumber(current)]; |
| 971 | BasicBlock* loop_end = current_loop->end; |
| 972 | current->set_loop_end(loop_end == nullptr ? BeyondEndSentinel() |
| 973 | : loop_end); |
| 974 | current_header = current_loop->header; |
| 975 | TRACE("id:%d is a loop header, increment loop depth to %d\n", |
| 976 | current->id().ToInt(), loop_depth); |
| 977 | } |
| 978 | |
| 979 | current->set_loop_depth(loop_depth); |
| 980 | |
| 981 | if (current->loop_header() == nullptr) { |
| 982 | TRACE("id:%d is not in a loop (depth == %d)\n", current->id().ToInt(), |
| 983 | current->loop_depth()); |
| 984 | } else { |
| 985 | TRACE("id:%d has loop header id:%d, (depth == %d)\n", |
| 986 | current->id().ToInt(), current->loop_header()->id().ToInt(), |
| 987 | current->loop_depth()); |
| 988 | } |
| 989 | } |
| 990 | } |
| 991 | |
| 992 | // Computes loop membership from the backedges of the control flow graph. |
| 993 | void ComputeLoopInfo(ZoneVector<SpecialRPOStackFrame>* queue, |
| 994 | size_t num_loops, ZoneVector<Backedge>* backedges) { |
| 995 | // Extend existing loop membership vectors. |
| 996 | for (LoopInfo& loop : loops_) { |
| 997 | loop.members->Resize(static_cast<int>(schedule_->BasicBlockCount()), |
| 998 | zone_); |
| 999 | } |
| 1000 | |
| 1001 | // Extend loop information vector. |
| 1002 | loops_.resize(num_loops, LoopInfo()); |
| 1003 | |
| 1004 | // Compute loop membership starting from backedges. |
| 1005 | // O(max(loop_depth) * max(|loop|) |
| 1006 | for (size_t i = 0; i < backedges->size(); i++) { |
| 1007 | BasicBlock* member = backedges->at(i).first; |
| 1008 | BasicBlock* header = member->SuccessorAt(backedges->at(i).second); |
| 1009 | size_t loop_num = GetLoopNumber(header); |
| 1010 | if (loops_[loop_num].header == nullptr) { |
| 1011 | loops_[loop_num].header = header; |
| 1012 | loops_[loop_num].members = zone_->New<BitVector>( |
| 1013 | static_cast<int>(schedule_->BasicBlockCount()), zone_); |
| 1014 | } |
| 1015 | |
| 1016 | int queue_length = 0; |
| 1017 | if (member != header) { |
| 1018 | // As long as the header doesn't have a backedge to itself, |
| 1019 | // Push the member onto the queue and process its predecessors. |
| 1020 | if (!loops_[loop_num].members->Contains(member->id().ToInt())) { |
| 1021 | loops_[loop_num].members->Add(member->id().ToInt()); |
| 1022 | } |
| 1023 | (*queue)[queue_length++].block = member; |
| 1024 | } |
| 1025 | |
| 1026 | // Propagate loop membership backwards. All predecessors of M up to the |
| 1027 | // loop header H are members of the loop too. O(|blocks between M and H|). |
| 1028 | while (queue_length > 0) { |
| 1029 | BasicBlock* block = (*queue)[--queue_length].block; |
| 1030 | for (size_t j = 0; j < block->PredecessorCount(); j++) { |
| 1031 | BasicBlock* pred = block->PredecessorAt(j); |
| 1032 | if (pred != header) { |
| 1033 | if (!loops_[loop_num].members->Contains(pred->id().ToInt())) { |
| 1034 | loops_[loop_num].members->Add(pred->id().ToInt()); |
| 1035 | (*queue)[queue_length++].block = pred; |
| 1036 | } |
| 1037 | } |
| 1038 | } |
| 1039 | } |
| 1040 | } |
| 1041 | } |
| 1042 | |
| 1043 | #if DEBUG |
| 1044 | void PrintRPO() { |
| 1045 | StdoutStream os; |
| 1046 | os << "RPO with " << loops_.size() << " loops"; |
| 1047 | if (loops_.size() > 0) { |
| 1048 | os << " ("; |
| 1049 | for (size_t i = 0; i < loops_.size(); i++) { |
| 1050 | if (i > 0) os << " "; |
| 1051 | os << "id:" << loops_[i].header->id(); |
| 1052 | } |
| 1053 | os << ")"; |
| 1054 | } |
| 1055 | os << ":\n"; |
| 1056 | |
| 1057 | for (BasicBlock* block = order_; block != nullptr; |
| 1058 | block = block->rpo_next()) { |
| 1059 | os << std::setw(5) << "B" << block->rpo_number() << ":"; |
| 1060 | for (size_t i = 0; i < loops_.size(); i++) { |
| 1061 | bool range = loops_[i].header->LoopContains(block); |
| 1062 | bool membership = loops_[i].header != block && range; |
| 1063 | os << (membership ? " |" : " "); |
| 1064 | os << (range ? "x" : " "); |
| 1065 | } |
| 1066 | os << " id:" << block->id() << ": "; |
| 1067 | if (block->loop_end() != nullptr) { |
| 1068 | os << " range: [B" << block->rpo_number() << ", B" |
| 1069 | << block->loop_end()->rpo_number() << ")"; |
| 1070 | } |
| 1071 | if (block->loop_header() != nullptr) { |
| 1072 | os << " header: id:" << block->loop_header()->id(); |
| 1073 | } |
| 1074 | if (block->loop_depth() > 0) { |
| 1075 | os << " depth: " << block->loop_depth(); |
| 1076 | } |
| 1077 | os << "\n"; |
| 1078 | } |
| 1079 | } |
| 1080 | |
| 1081 | void VerifySpecialRPO() { |
| 1082 | BasicBlockVector* order = schedule_->rpo_order(); |
| 1083 | DCHECK_LT(0, order->size())((void) 0); |
| 1084 | DCHECK_EQ(0, (*order)[0]->id().ToInt())((void) 0); // entry should be first. |
| 1085 | |
| 1086 | for (size_t i = 0; i < loops_.size(); i++) { |
| 1087 | LoopInfo* loop = &loops_[i]; |
| 1088 | BasicBlock* header = loop->header; |
| 1089 | BasicBlock* end = header->loop_end(); |
| 1090 | |
| 1091 | DCHECK_NOT_NULL(header)((void) 0); |
| 1092 | DCHECK_LE(0, header->rpo_number())((void) 0); |
| 1093 | DCHECK_LT(header->rpo_number(), order->size())((void) 0); |
| 1094 | DCHECK_NOT_NULL(end)((void) 0); |
| 1095 | DCHECK_LE(end->rpo_number(), order->size())((void) 0); |
| 1096 | DCHECK_GT(end->rpo_number(), header->rpo_number())((void) 0); |
| 1097 | DCHECK_NE(header->loop_header(), header)((void) 0); |
| 1098 | |
| 1099 | // Verify the start ... end list relationship. |
| 1100 | int links = 0; |
| 1101 | BasicBlock* block = loop->start; |
| 1102 | DCHECK_EQ(header, block)((void) 0); |
| 1103 | bool end_found; |
| 1104 | while (true) { |
| 1105 | if (block == nullptr || block == loop->end) { |
| 1106 | end_found = (loop->end == block); |
| 1107 | break; |
| 1108 | } |
| 1109 | // The list should be in same order as the final result. |
| 1110 | DCHECK(block->rpo_number() == links + header->rpo_number())((void) 0); |
| 1111 | links++; |
| 1112 | block = block->rpo_next(); |
| 1113 | DCHECK_LT(links, static_cast<int>(2 * order->size()))((void) 0); // cycle? |
| 1114 | } |
| 1115 | DCHECK_LT(0, links)((void) 0); |
| 1116 | DCHECK_EQ(links, end->rpo_number() - header->rpo_number())((void) 0); |
| 1117 | DCHECK(end_found)((void) 0); |
| 1118 | |
| 1119 | // Check loop depth of the header. |
| 1120 | int loop_depth = 0; |
| 1121 | for (LoopInfo* outer = loop; outer != nullptr; outer = outer->prev) { |
| 1122 | loop_depth++; |
| 1123 | } |
| 1124 | DCHECK_EQ(loop_depth, header->loop_depth())((void) 0); |
| 1125 | |
| 1126 | // Check the contiguousness of loops. |
| 1127 | int count = 0; |
| 1128 | for (int j = 0; j < static_cast<int>(order->size()); j++) { |
| 1129 | block = order->at(j); |
| 1130 | DCHECK_EQ(block->rpo_number(), j)((void) 0); |
| 1131 | if (j < header->rpo_number() || j >= end->rpo_number()) { |
| 1132 | DCHECK(!header->LoopContains(block))((void) 0); |
| 1133 | } else { |
| 1134 | DCHECK(header->LoopContains(block))((void) 0); |
| 1135 | DCHECK_GE(block->loop_depth(), loop_depth)((void) 0); |
| 1136 | count++; |
| 1137 | } |
| 1138 | } |
| 1139 | DCHECK_EQ(links, count)((void) 0); |
| 1140 | } |
| 1141 | } |
| 1142 | #endif // DEBUG |
| 1143 | |
| 1144 | Zone* zone_; |
| 1145 | Schedule* schedule_; |
| 1146 | BasicBlock* order_; |
| 1147 | BasicBlock* beyond_end_; |
| 1148 | ZoneVector<LoopInfo> loops_; |
| 1149 | ZoneVector<Backedge> backedges_; |
| 1150 | ZoneVector<SpecialRPOStackFrame> stack_; |
| 1151 | size_t previous_block_count_; |
| 1152 | ZoneVector<BasicBlock*> const empty_; |
| 1153 | }; |
| 1154 | |
| 1155 | |
| 1156 | BasicBlockVector* Scheduler::ComputeSpecialRPO(Zone* zone, Schedule* schedule) { |
| 1157 | SpecialRPONumberer numberer(zone, schedule); |
| 1158 | numberer.ComputeSpecialRPO(); |
| 1159 | numberer.SerializeRPOIntoSchedule(); |
| 1160 | numberer.PrintAndVerifySpecialRPO(); |
| 1161 | return schedule->rpo_order(); |
| 1162 | } |
| 1163 | |
| 1164 | |
| 1165 | void Scheduler::ComputeSpecialRPONumbering() { |
| 1166 | TRACE("--- COMPUTING SPECIAL RPO ----------------------------------\n"); |
| 1167 | |
| 1168 | // Compute the special reverse-post-order for basic blocks. |
| 1169 | special_rpo_ = zone_->New<SpecialRPONumberer>(zone_, schedule_); |
| 1170 | special_rpo_->ComputeSpecialRPO(); |
| 1171 | } |
| 1172 | |
| 1173 | BasicBlock* Scheduler::GetCommonDominatorIfCached(BasicBlock* b1, |
| 1174 | BasicBlock* b2) { |
| 1175 | auto entry1 = common_dominator_cache_.find(b1->id().ToInt()); |
| 1176 | if (entry1 == common_dominator_cache_.end()) return nullptr; |
| 1177 | auto entry2 = entry1->second->find(b2->id().ToInt()); |
| 1178 | if (entry2 == entry1->second->end()) return nullptr; |
| 1179 | return entry2->second; |
| 1180 | } |
| 1181 | |
| 1182 | BasicBlock* Scheduler::GetCommonDominator(BasicBlock* b1, BasicBlock* b2) { |
| 1183 | // A very common fast case: |
| 1184 | if (b1 == b2) return b1; |
| 1185 | // Try to find the common dominator by walking, if there is a chance of |
| 1186 | // finding it quickly. |
| 1187 | constexpr int kCacheGranularity = 63; |
| 1188 | STATIC_ASSERT((kCacheGranularity & (kCacheGranularity + 1)) == 0)static_assert((kCacheGranularity & (kCacheGranularity + 1 )) == 0, "(kCacheGranularity & (kCacheGranularity + 1)) == 0" ); |
| 1189 | int depth_difference = b1->dominator_depth() - b2->dominator_depth(); |
| 1190 | if (depth_difference > -kCacheGranularity && |
| 1191 | depth_difference < kCacheGranularity) { |
| 1192 | for (int i = 0; i < kCacheGranularity; i++) { |
| 1193 | if (b1->dominator_depth() < b2->dominator_depth()) { |
| 1194 | b2 = b2->dominator(); |
| 1195 | } else { |
| 1196 | b1 = b1->dominator(); |
| 1197 | } |
| 1198 | if (b1 == b2) return b1; |
| 1199 | } |
| 1200 | // We might fall out of the loop here if the dominator tree has several |
| 1201 | // deep "parallel" subtrees. |
| 1202 | } |
| 1203 | // If it'd be a long walk, take the bus instead (i.e. use the cache). |
| 1204 | // To keep memory consumption low, there'll be a bus stop every 64 blocks. |
| 1205 | // First, walk to the nearest bus stop. |
| 1206 | if (b1->dominator_depth() < b2->dominator_depth()) std::swap(b1, b2); |
| 1207 | while ((b1->dominator_depth() & kCacheGranularity) != 0) { |
| 1208 | if (V8_LIKELY(b1->dominator_depth() > b2->dominator_depth())(__builtin_expect(!!(b1->dominator_depth() > b2->dominator_depth ()), 1))) { |
| 1209 | b1 = b1->dominator(); |
| 1210 | } else { |
| 1211 | b2 = b2->dominator(); |
| 1212 | } |
| 1213 | if (b1 == b2) return b1; |
| 1214 | } |
| 1215 | // Then, walk from bus stop to bus stop until we either find a bus (i.e. an |
| 1216 | // existing cache entry) or the result. Make a list of any empty bus stops |
| 1217 | // we'd like to populate for next time. |
| 1218 | constexpr int kMaxNewCacheEntries = 2 * 50; // Must be even. |
| 1219 | // This array stores a flattened list of pairs, e.g. if after finding the |
| 1220 | // {result}, we want to cache [(B11, B12) -> result, (B21, B22) -> result], |
| 1221 | // then we store [11, 12, 21, 22] here. |
| 1222 | int new_cache_entries[kMaxNewCacheEntries]; |
| 1223 | // Next free slot in {new_cache_entries}. |
| 1224 | int new_cache_entries_cursor = 0; |
| 1225 | while (b1 != b2) { |
| 1226 | if ((b1->dominator_depth() & kCacheGranularity) == 0) { |
| 1227 | BasicBlock* maybe_cache_hit = GetCommonDominatorIfCached(b1, b2); |
| 1228 | if (maybe_cache_hit != nullptr) { |
| 1229 | b1 = b2 = maybe_cache_hit; |
Although the value stored to 'b2' is used in the enclosing expression, the value is never actually read from 'b2' | |
| 1230 | break; |
| 1231 | } else if (new_cache_entries_cursor < kMaxNewCacheEntries) { |
| 1232 | new_cache_entries[new_cache_entries_cursor++] = b1->id().ToInt(); |
| 1233 | new_cache_entries[new_cache_entries_cursor++] = b2->id().ToInt(); |
| 1234 | } |
| 1235 | } |
| 1236 | if (V8_LIKELY(b1->dominator_depth() > b2->dominator_depth())(__builtin_expect(!!(b1->dominator_depth() > b2->dominator_depth ()), 1))) { |
| 1237 | b1 = b1->dominator(); |
| 1238 | } else { |
| 1239 | b2 = b2->dominator(); |
| 1240 | } |
| 1241 | } |
| 1242 | // Lastly, create new cache entries we noted down earlier. |
| 1243 | BasicBlock* result = b1; |
| 1244 | for (int i = 0; i < new_cache_entries_cursor;) { |
| 1245 | int id1 = new_cache_entries[i++]; |
| 1246 | int id2 = new_cache_entries[i++]; |
| 1247 | ZoneMap<int, BasicBlock*>* mapping; |
| 1248 | auto entry = common_dominator_cache_.find(id1); |
| 1249 | if (entry == common_dominator_cache_.end()) { |
| 1250 | mapping = zone_->New<ZoneMap<int, BasicBlock*>>(zone_); |
| 1251 | common_dominator_cache_[id1] = mapping; |
| 1252 | } else { |
| 1253 | mapping = entry->second; |
| 1254 | } |
| 1255 | // If there was an existing entry, we would have found it earlier. |
| 1256 | DCHECK_EQ(mapping->find(id2), mapping->end())((void) 0); |
| 1257 | mapping->insert({id2, result}); |
| 1258 | } |
| 1259 | return result; |
| 1260 | } |
| 1261 | |
| 1262 | void Scheduler::PropagateImmediateDominators(BasicBlock* block) { |
| 1263 | for (/*nop*/; block != nullptr; block = block->rpo_next()) { |
| 1264 | auto pred = block->predecessors().begin(); |
| 1265 | auto end = block->predecessors().end(); |
| 1266 | DCHECK(pred != end)((void) 0); // All blocks except start have predecessors. |
| 1267 | BasicBlock* dominator = *pred; |
| 1268 | bool deferred = dominator->deferred(); |
| 1269 | // For multiple predecessors, walk up the dominator tree until a common |
| 1270 | // dominator is found. Visitation order guarantees that all predecessors |
| 1271 | // except for backwards edges have been visited. |
| 1272 | // We use a one-element cache for previously-seen dominators. This gets |
| 1273 | // hit a lot for functions that have long chains of diamonds, and in |
| 1274 | // those cases turns quadratic into linear complexity. |
| 1275 | BasicBlock* cache = nullptr; |
| 1276 | for (++pred; pred != end; ++pred) { |
| 1277 | // Don't examine backwards edges. |
| 1278 | if ((*pred)->dominator_depth() < 0) continue; |
| 1279 | if ((*pred)->dominator_depth() > 3 && |
| 1280 | ((*pred)->dominator()->dominator() == cache || |
| 1281 | (*pred)->dominator()->dominator()->dominator() == cache)) { |
| 1282 | // Nothing to do, the last iteration covered this case. |
| 1283 | DCHECK_EQ(dominator, BasicBlock::GetCommonDominator(dominator, *pred))((void) 0); |
| 1284 | } else { |
| 1285 | dominator = BasicBlock::GetCommonDominator(dominator, *pred); |
| 1286 | } |
| 1287 | cache = (*pred)->dominator(); |
| 1288 | deferred = deferred & (*pred)->deferred(); |
| 1289 | } |
| 1290 | block->set_dominator(dominator); |
| 1291 | block->set_dominator_depth(dominator->dominator_depth() + 1); |
| 1292 | block->set_deferred(deferred | block->deferred()); |
| 1293 | TRACE("Block id:%d's idom is id:%d, depth = %d\n", block->id().ToInt(), |
| 1294 | dominator->id().ToInt(), block->dominator_depth()); |
| 1295 | } |
| 1296 | } |
| 1297 | |
| 1298 | void Scheduler::GenerateDominatorTree(Schedule* schedule) { |
| 1299 | // Seed start block to be the first dominator. |
| 1300 | schedule->start()->set_dominator_depth(0); |
| 1301 | |
| 1302 | // Build the block dominator tree resulting from the above seed. |
| 1303 | PropagateImmediateDominators(schedule->start()->rpo_next()); |
| 1304 | } |
| 1305 | |
| 1306 | void Scheduler::GenerateDominatorTree() { |
| 1307 | TRACE("--- IMMEDIATE BLOCK DOMINATORS -----------------------------\n"); |
| 1308 | GenerateDominatorTree(schedule_); |
| 1309 | } |
| 1310 | |
| 1311 | // ----------------------------------------------------------------------------- |
| 1312 | // Phase 3: Prepare use counts for nodes. |
| 1313 | |
| 1314 | |
| 1315 | class PrepareUsesVisitor { |
| 1316 | public: |
| 1317 | explicit PrepareUsesVisitor(Scheduler* scheduler, Graph* graph, Zone* zone) |
| 1318 | : scheduler_(scheduler), |
| 1319 | schedule_(scheduler->schedule_), |
| 1320 | graph_(graph), |
| 1321 | visited_(graph_->NodeCount(), false, zone), |
| 1322 | stack_(zone) {} |
| 1323 | |
| 1324 | void Run() { |
| 1325 | InitializePlacement(graph_->end()); |
| 1326 | while (!stack_.empty()) { |
| 1327 | Node* node = stack_.top(); |
| 1328 | stack_.pop(); |
| 1329 | VisitInputs(node); |
| 1330 | } |
| 1331 | } |
| 1332 | |
| 1333 | private: |
| 1334 | void InitializePlacement(Node* node) { |
| 1335 | TRACE("Pre #%d:%s\n", node->id(), node->op()->mnemonic()); |
| 1336 | DCHECK(!Visited(node))((void) 0); |
| 1337 | if (scheduler_->InitializePlacement(node) == Scheduler::kFixed) { |
| 1338 | // Fixed nodes are always roots for schedule late. |
| 1339 | scheduler_->schedule_root_nodes_.push_back(node); |
| 1340 | if (!schedule_->IsScheduled(node)) { |
| 1341 | // Make sure root nodes are scheduled in their respective blocks. |
| 1342 | TRACE("Scheduling fixed position node #%d:%s\n", node->id(), |
| 1343 | node->op()->mnemonic()); |
| 1344 | IrOpcode::Value opcode = node->opcode(); |
| 1345 | BasicBlock* block = |
| 1346 | opcode == IrOpcode::kParameter |
| 1347 | ? schedule_->start() |
| 1348 | : schedule_->block(NodeProperties::GetControlInput(node)); |
| 1349 | DCHECK_NOT_NULL(block)((void) 0); |
| 1350 | schedule_->AddNode(block, node); |
| 1351 | } |
| 1352 | } |
| 1353 | stack_.push(node); |
| 1354 | visited_[node->id()] = true; |
| 1355 | } |
| 1356 | |
| 1357 | void VisitInputs(Node* node) { |
| 1358 | DCHECK_NE(scheduler_->GetPlacement(node), Scheduler::kUnknown)((void) 0); |
| 1359 | bool is_scheduled = schedule_->IsScheduled(node); |
| 1360 | base::Optional<int> coupled_control_edge = |
| 1361 | scheduler_->GetCoupledControlEdge(node); |
| 1362 | for (auto edge : node->input_edges()) { |
| 1363 | Node* to = edge.to(); |
| 1364 | DCHECK_EQ(node, edge.from())((void) 0); |
| 1365 | if (!Visited(to)) { |
| 1366 | InitializePlacement(to); |
| 1367 | } |
| 1368 | TRACE("PostEdge #%d:%s->#%d:%s\n", node->id(), node->op()->mnemonic(), |
| 1369 | to->id(), to->op()->mnemonic()); |
| 1370 | DCHECK_NE(scheduler_->GetPlacement(to), Scheduler::kUnknown)((void) 0); |
| 1371 | if (!is_scheduled && edge.index() != coupled_control_edge) { |
| 1372 | scheduler_->IncrementUnscheduledUseCount(to, node); |
| 1373 | } |
| 1374 | } |
| 1375 | } |
| 1376 | |
| 1377 | bool Visited(Node* node) { return visited_[node->id()]; } |
| 1378 | |
| 1379 | Scheduler* scheduler_; |
| 1380 | Schedule* schedule_; |
| 1381 | Graph* graph_; |
| 1382 | BoolVector visited_; |
| 1383 | ZoneStack<Node*> stack_; |
| 1384 | }; |
| 1385 | |
| 1386 | |
| 1387 | void Scheduler::PrepareUses() { |
| 1388 | TRACE("--- PREPARE USES -------------------------------------------\n"); |
| 1389 | |
| 1390 | // Count the uses of every node, which is used to ensure that all of a |
| 1391 | // node's uses are scheduled before the node itself. |
| 1392 | PrepareUsesVisitor prepare_uses(this, graph_, zone_); |
| 1393 | prepare_uses.Run(); |
| 1394 | } |
| 1395 | |
| 1396 | |
| 1397 | // ----------------------------------------------------------------------------- |
| 1398 | // Phase 4: Schedule nodes early. |
| 1399 | |
| 1400 | |
| 1401 | class ScheduleEarlyNodeVisitor { |
| 1402 | public: |
| 1403 | ScheduleEarlyNodeVisitor(Zone* zone, Scheduler* scheduler) |
| 1404 | : scheduler_(scheduler), schedule_(scheduler->schedule_), queue_(zone) {} |
| 1405 | |
| 1406 | // Run the schedule early algorithm on a set of fixed root nodes. |
| 1407 | void Run(NodeVector* roots) { |
| 1408 | for (Node* const root : *roots) { |
| 1409 | queue_.push(root); |
| 1410 | } |
| 1411 | |
| 1412 | while (!queue_.empty()) { |
| 1413 | scheduler_->tick_counter_->TickAndMaybeEnterSafepoint(); |
| 1414 | VisitNode(queue_.front()); |
| 1415 | queue_.pop(); |
| 1416 | } |
| 1417 | } |
| 1418 | |
| 1419 | private: |
| 1420 | // Visits one node from the queue and propagates its current schedule early |
| 1421 | // position to all uses. This in turn might push more nodes onto the queue. |
| 1422 | void VisitNode(Node* node) { |
| 1423 | Scheduler::SchedulerData* data = scheduler_->GetData(node); |
| 1424 | |
| 1425 | // Fixed nodes already know their schedule early position. |
| 1426 | if (scheduler_->GetPlacement(node) == Scheduler::kFixed) { |
| 1427 | data->minimum_block_ = schedule_->block(node); |
| 1428 | TRACE("Fixing #%d:%s minimum_block = id:%d, dominator_depth = %d\n", |
| 1429 | node->id(), node->op()->mnemonic(), |
| 1430 | data->minimum_block_->id().ToInt(), |
| 1431 | data->minimum_block_->dominator_depth()); |
| 1432 | } |
| 1433 | |
| 1434 | // No need to propagate unconstrained schedule early positions. |
| 1435 | if (data->minimum_block_ == schedule_->start()) return; |
| 1436 | |
| 1437 | // Propagate schedule early position. |
| 1438 | DCHECK_NOT_NULL(data->minimum_block_)((void) 0); |
| 1439 | for (auto use : node->uses()) { |
| 1440 | if (scheduler_->IsLive(use)) { |
| 1441 | PropagateMinimumPositionToNode(data->minimum_block_, use); |
| 1442 | } |
| 1443 | } |
| 1444 | } |
| 1445 | |
| 1446 | // Propagates {block} as another minimum position into the given {node}. This |
| 1447 | // has the net effect of computing the minimum dominator block of {node} that |
| 1448 | // still post-dominates all inputs to {node} when the queue is processed. |
| 1449 | void PropagateMinimumPositionToNode(BasicBlock* block, Node* node) { |
| 1450 | Scheduler::SchedulerData* data = scheduler_->GetData(node); |
| 1451 | |
| 1452 | // No need to propagate to fixed node, it's guaranteed to be a root. |
| 1453 | if (scheduler_->GetPlacement(node) == Scheduler::kFixed) return; |
| 1454 | |
| 1455 | // Coupled nodes influence schedule early position of their control. |
| 1456 | if (scheduler_->GetPlacement(node) == Scheduler::kCoupled) { |
| 1457 | Node* control = NodeProperties::GetControlInput(node); |
| 1458 | PropagateMinimumPositionToNode(block, control); |
| 1459 | } |
| 1460 | |
| 1461 | // Propagate new position if it is deeper down the dominator tree than the |
| 1462 | // current. Note that all inputs need to have minimum block position inside |
| 1463 | // the dominator chain of {node}'s minimum block position. |
| 1464 | DCHECK(InsideSameDominatorChain(block, data->minimum_block_))((void) 0); |
| 1465 | if (block->dominator_depth() > data->minimum_block_->dominator_depth()) { |
| 1466 | data->minimum_block_ = block; |
| 1467 | queue_.push(node); |
| 1468 | TRACE("Propagating #%d:%s minimum_block = id:%d, dominator_depth = %d\n", |
| 1469 | node->id(), node->op()->mnemonic(), |
| 1470 | data->minimum_block_->id().ToInt(), |
| 1471 | data->minimum_block_->dominator_depth()); |
| 1472 | } |
| 1473 | } |
| 1474 | |
| 1475 | #if DEBUG |
| 1476 | bool InsideSameDominatorChain(BasicBlock* b1, BasicBlock* b2) { |
| 1477 | BasicBlock* dominator = BasicBlock::GetCommonDominator(b1, b2); |
| 1478 | return dominator == b1 || dominator == b2; |
| 1479 | } |
| 1480 | #endif |
| 1481 | |
| 1482 | Scheduler* scheduler_; |
| 1483 | Schedule* schedule_; |
| 1484 | ZoneQueue<Node*> queue_; |
| 1485 | }; |
| 1486 | |
| 1487 | |
| 1488 | void Scheduler::ScheduleEarly() { |
| 1489 | if (!special_rpo_->HasLoopBlocks()) { |
| 1490 | TRACE("--- NO LOOPS SO SKIPPING SCHEDULE EARLY --------------------\n"); |
| 1491 | return; |
| 1492 | } |
| 1493 | |
| 1494 | TRACE("--- SCHEDULE EARLY -----------------------------------------\n"); |
| 1495 | if (FLAG_trace_turbo_scheduler) { |
| 1496 | TRACE("roots: "); |
| 1497 | for (Node* node : schedule_root_nodes_) { |
| 1498 | TRACE("#%d:%s ", node->id(), node->op()->mnemonic()); |
| 1499 | } |
| 1500 | TRACE("\n"); |
| 1501 | } |
| 1502 | |
| 1503 | // Compute the minimum block for each node thereby determining the earliest |
| 1504 | // position each node could be placed within a valid schedule. |
| 1505 | ScheduleEarlyNodeVisitor schedule_early_visitor(zone_, this); |
| 1506 | schedule_early_visitor.Run(&schedule_root_nodes_); |
| 1507 | } |
| 1508 | |
| 1509 | |
| 1510 | // ----------------------------------------------------------------------------- |
| 1511 | // Phase 5: Schedule nodes late. |
| 1512 | |
| 1513 | |
| 1514 | class ScheduleLateNodeVisitor { |
| 1515 | public: |
| 1516 | ScheduleLateNodeVisitor(Zone* zone, Scheduler* scheduler) |
| 1517 | : zone_(zone), |
| 1518 | scheduler_(scheduler), |
| 1519 | schedule_(scheduler_->schedule_), |
| 1520 | marked_(scheduler->zone_), |
| 1521 | marking_queue_(scheduler->zone_) {} |
| 1522 | |
| 1523 | // Run the schedule late algorithm on a set of fixed root nodes. |
| 1524 | void Run(NodeVector* roots) { |
| 1525 | for (Node* const root : *roots) { |
| 1526 | ProcessQueue(root); |
| 1527 | } |
| 1528 | } |
| 1529 | |
| 1530 | private: |
| 1531 | void ProcessQueue(Node* root) { |
| 1532 | ZoneQueue<Node*>* queue = &(scheduler_->schedule_queue_); |
| 1533 | for (Node* node : root->inputs()) { |
| 1534 | // Don't schedule coupled nodes on their own. |
| 1535 | if (scheduler_->GetPlacement(node) == Scheduler::kCoupled) { |
| 1536 | node = NodeProperties::GetControlInput(node); |
| 1537 | } |
| 1538 | |
| 1539 | // Test schedulability condition by looking at unscheduled use count. |
| 1540 | if (scheduler_->GetData(node)->unscheduled_count_ != 0) continue; |
| 1541 | |
| 1542 | queue->push(node); |
| 1543 | do { |
| 1544 | scheduler_->tick_counter_->TickAndMaybeEnterSafepoint(); |
| 1545 | Node* const n = queue->front(); |
| 1546 | queue->pop(); |
| 1547 | VisitNode(n); |
| 1548 | } while (!queue->empty()); |
| 1549 | } |
| 1550 | } |
| 1551 | |
| 1552 | // Visits one node from the queue of schedulable nodes and determines its |
| 1553 | // schedule late position. Also hoists nodes out of loops to find a more |
| 1554 | // optimal scheduling position. |
| 1555 | void VisitNode(Node* node) { |
| 1556 | DCHECK_EQ(0, scheduler_->GetData(node)->unscheduled_count_)((void) 0); |
| 1557 | |
| 1558 | // Don't schedule nodes that are already scheduled. |
| 1559 | if (schedule_->IsScheduled(node)) return; |
| 1560 | DCHECK_EQ(Scheduler::kSchedulable, scheduler_->GetPlacement(node))((void) 0); |
| 1561 | |
| 1562 | // Determine the dominating block for all of the uses of this node. It is |
| 1563 | // the latest block that this node can be scheduled in. |
| 1564 | TRACE("Scheduling #%d:%s\n", node->id(), node->op()->mnemonic()); |
| 1565 | BasicBlock* block = GetCommonDominatorOfUses(node); |
| 1566 | DCHECK_NOT_NULL(block)((void) 0); |
| 1567 | |
| 1568 | // The schedule early block dominates the schedule late block. |
| 1569 | BasicBlock* min_block = scheduler_->GetData(node)->minimum_block_; |
| 1570 | DCHECK_EQ(min_block, BasicBlock::GetCommonDominator(block, min_block))((void) 0); |
| 1571 | |
| 1572 | TRACE( |
| 1573 | "Schedule late of #%d:%s is id:%d at loop depth %d, minimum = id:%d\n", |
| 1574 | node->id(), node->op()->mnemonic(), block->id().ToInt(), |
| 1575 | block->loop_depth(), min_block->id().ToInt()); |
| 1576 | |
| 1577 | // Hoist nodes out of loops if possible. Nodes can be hoisted iteratively |
| 1578 | // into enclosing loop pre-headers until they would precede their schedule |
| 1579 | // early position. |
| 1580 | BasicBlock* hoist_block = GetHoistBlock(block); |
| 1581 | if (hoist_block && |
| 1582 | hoist_block->dominator_depth() >= min_block->dominator_depth()) { |
| 1583 | DCHECK(scheduler_->special_rpo_->HasLoopBlocks())((void) 0); |
| 1584 | do { |
| 1585 | TRACE(" hoisting #%d:%s to block id:%d\n", node->id(), |
| 1586 | node->op()->mnemonic(), hoist_block->id().ToInt()); |
| 1587 | DCHECK_LT(hoist_block->loop_depth(), block->loop_depth())((void) 0); |
| 1588 | block = hoist_block; |
| 1589 | hoist_block = GetHoistBlock(hoist_block); |
| 1590 | } while (hoist_block && |
| 1591 | hoist_block->dominator_depth() >= min_block->dominator_depth()); |
| 1592 | } else if (scheduler_->flags_ & Scheduler::kSplitNodes) { |
| 1593 | // Split the {node} if beneficial and return the new {block} for it. |
| 1594 | block = SplitNode(block, node); |
| 1595 | } |
| 1596 | |
| 1597 | // Schedule the node or a floating control structure. |
| 1598 | if (IrOpcode::IsMergeOpcode(node->opcode())) { |
| 1599 | ScheduleFloatingControl(block, node); |
| 1600 | } else if (node->opcode() == IrOpcode::kFinishRegion) { |
| 1601 | ScheduleRegion(block, node); |
| 1602 | } else { |
| 1603 | ScheduleNode(block, node); |
| 1604 | } |
| 1605 | } |
| 1606 | |
| 1607 | bool IsMarked(BasicBlock* block) const { |
| 1608 | DCHECK_LT(block->id().ToSize(), marked_.size())((void) 0); |
| 1609 | return marked_[block->id().ToSize()]; |
| 1610 | } |
| 1611 | |
| 1612 | void Mark(BasicBlock* block) { marked_[block->id().ToSize()] = true; } |
| 1613 | |
| 1614 | // Mark {block} and push its non-marked predecessor on the marking queue. |
| 1615 | void MarkBlock(BasicBlock* block) { |
| 1616 | DCHECK_LT(block->id().ToSize(), marked_.size())((void) 0); |
| 1617 | Mark(block); |
| 1618 | for (BasicBlock* pred_block : block->predecessors()) { |
| 1619 | if (IsMarked(pred_block)) continue; |
| 1620 | marking_queue_.push_back(pred_block); |
| 1621 | } |
| 1622 | } |
| 1623 | |
| 1624 | BasicBlock* SplitNode(BasicBlock* block, Node* node) { |
| 1625 | // For now, we limit splitting to pure nodes. |
| 1626 | if (!node->op()->HasProperty(Operator::kPure)) return block; |
| 1627 | // TODO(titzer): fix the special case of splitting of projections. |
| 1628 | if (node->opcode() == IrOpcode::kProjection) return block; |
| 1629 | |
| 1630 | // The {block} is common dominator of all uses of {node}, so we cannot |
| 1631 | // split anything unless the {block} has at least two successors. |
| 1632 | DCHECK_EQ(block, GetCommonDominatorOfUses(node))((void) 0); |
| 1633 | if (block->SuccessorCount() < 2) return block; |
| 1634 | |
| 1635 | // Clear marking bits. |
| 1636 | DCHECK(marking_queue_.empty())((void) 0); |
| 1637 | std::fill(marked_.begin(), marked_.end(), false); |
| 1638 | marked_.resize(schedule_->BasicBlockCount() + 1, false); |
| 1639 | |
| 1640 | // Check if the {node} has uses in {block}. |
| 1641 | for (Edge edge : node->use_edges()) { |
| 1642 | if (!scheduler_->IsLive(edge.from())) continue; |
| 1643 | BasicBlock* use_block = GetBlockForUse(edge); |
| 1644 | if (use_block == nullptr || IsMarked(use_block)) continue; |
| 1645 | if (use_block == block) { |
| 1646 | TRACE(" not splitting #%d:%s, it is used in id:%d\n", node->id(), |
| 1647 | node->op()->mnemonic(), block->id().ToInt()); |
| 1648 | marking_queue_.clear(); |
| 1649 | return block; |
| 1650 | } |
| 1651 | MarkBlock(use_block); |
| 1652 | } |
| 1653 | |
| 1654 | // Compute transitive marking closure; a block is marked if all its |
| 1655 | // successors are marked. |
| 1656 | do { |
| 1657 | BasicBlock* top_block = marking_queue_.front(); |
| 1658 | marking_queue_.pop_front(); |
| 1659 | if (IsMarked(top_block)) continue; |
| 1660 | bool marked = true; |
| 1661 | for (BasicBlock* successor : top_block->successors()) { |
| 1662 | if (!IsMarked(successor)) { |
| 1663 | marked = false; |
| 1664 | break; |
| 1665 | } |
| 1666 | } |
| 1667 | if (marked) MarkBlock(top_block); |
| 1668 | } while (!marking_queue_.empty()); |
| 1669 | |
| 1670 | // If the (common dominator) {block} is marked, we know that all paths from |
| 1671 | // {block} to the end contain at least one use of {node}, and hence there's |
| 1672 | // no point in splitting the {node} in this case. |
| 1673 | if (IsMarked(block)) { |
| 1674 | TRACE(" not splitting #%d:%s, its common dominator id:%d is perfect\n", |
| 1675 | node->id(), node->op()->mnemonic(), block->id().ToInt()); |
| 1676 | return block; |
| 1677 | } |
| 1678 | |
| 1679 | // Split {node} for uses according to the previously computed marking |
| 1680 | // closure. Every marking partition has a unique dominator, which get's a |
| 1681 | // copy of the {node} with the exception of the first partition, which get's |
| 1682 | // the {node} itself. |
| 1683 | ZoneMap<BasicBlock*, Node*> dominators(scheduler_->zone_); |
| 1684 | for (Edge edge : node->use_edges()) { |
| 1685 | if (!scheduler_->IsLive(edge.from())) continue; |
| 1686 | BasicBlock* use_block = GetBlockForUse(edge); |
| 1687 | if (use_block == nullptr) continue; |
| 1688 | while (IsMarked(use_block->dominator())) { |
| 1689 | use_block = use_block->dominator(); |
| 1690 | } |
| 1691 | auto& use_node = dominators[use_block]; |
| 1692 | if (use_node == nullptr) { |
| 1693 | if (dominators.size() == 1u) { |
| 1694 | // Place the {node} at {use_block}. |
| 1695 | block = use_block; |
| 1696 | use_node = node; |
| 1697 | TRACE(" pushing #%d:%s down to id:%d\n", node->id(), |
| 1698 | node->op()->mnemonic(), block->id().ToInt()); |
| 1699 | } else { |
| 1700 | // Place a copy of {node} at {use_block}. |
| 1701 | use_node = CloneNode(node); |
| 1702 | TRACE(" cloning #%d:%s for id:%d\n", use_node->id(), |
| 1703 | use_node->op()->mnemonic(), use_block->id().ToInt()); |
| 1704 | scheduler_->schedule_queue_.push(use_node); |
| 1705 | } |
| 1706 | } |
| 1707 | edge.UpdateTo(use_node); |
| 1708 | } |
| 1709 | return block; |
| 1710 | } |
| 1711 | |
| 1712 | BasicBlock* GetHoistBlock(BasicBlock* block) { |
| 1713 | if (!scheduler_->special_rpo_->HasLoopBlocks()) return nullptr; |
| 1714 | if (block->IsLoopHeader()) return block->dominator(); |
| 1715 | // We have to check to make sure that the {block} dominates all |
| 1716 | // of the outgoing blocks. If it doesn't, then there is a path |
| 1717 | // out of the loop which does not execute this {block}, so we |
| 1718 | // can't hoist operations from this {block} out of the loop, as |
| 1719 | // that would introduce additional computations. |
| 1720 | if (BasicBlock* header_block = block->loop_header()) { |
| 1721 | for (BasicBlock* outgoing_block : |
| 1722 | scheduler_->special_rpo_->GetOutgoingBlocks(header_block)) { |
| 1723 | if (scheduler_->GetCommonDominator(block, outgoing_block) != block) { |
| 1724 | return nullptr; |
| 1725 | } |
| 1726 | } |
| 1727 | return header_block->dominator(); |
| 1728 | } |
| 1729 | return nullptr; |
| 1730 | } |
| 1731 | |
| 1732 | BasicBlock* GetCommonDominatorOfUses(Node* node) { |
| 1733 | BasicBlock* block = nullptr; |
| 1734 | for (Edge edge : node->use_edges()) { |
| 1735 | if (!scheduler_->IsLive(edge.from())) continue; |
| 1736 | BasicBlock* use_block = GetBlockForUse(edge); |
| 1737 | block = block == nullptr |
| 1738 | ? use_block |
| 1739 | : use_block == nullptr |
| 1740 | ? block |
| 1741 | : scheduler_->GetCommonDominator(block, use_block); |
| 1742 | } |
| 1743 | return block; |
| 1744 | } |
| 1745 | |
| 1746 | BasicBlock* FindPredecessorBlock(Node* node) { |
| 1747 | return scheduler_->control_flow_builder_->FindPredecessorBlock(node); |
| 1748 | } |
| 1749 | |
| 1750 | BasicBlock* GetBlockForUse(Edge edge) { |
| 1751 | // TODO(titzer): ignore uses from dead nodes (not visited in PrepareUses()). |
| 1752 | // Dead uses only occur if the graph is not trimmed before scheduling. |
| 1753 | Node* use = edge.from(); |
| 1754 | if (IrOpcode::IsPhiOpcode(use->opcode())) { |
| 1755 | // If the use is from a coupled (i.e. floating) phi, compute the common |
| 1756 | // dominator of its uses. This will not recurse more than one level. |
| 1757 | if (scheduler_->GetPlacement(use) == Scheduler::kCoupled) { |
| 1758 | TRACE(" inspecting uses of coupled #%d:%s\n", use->id(), |
| 1759 | use->op()->mnemonic()); |
| 1760 | // TODO(titzer): reenable once above TODO is addressed. |
| 1761 | // DCHECK_EQ(edge.to(), NodeProperties::GetControlInput(use)); |
| 1762 | return GetCommonDominatorOfUses(use); |
| 1763 | } |
| 1764 | // If the use is from a fixed (i.e. non-floating) phi, we use the |
| 1765 | // predecessor block of the corresponding control input to the merge. |
| 1766 | if (scheduler_->GetPlacement(use) == Scheduler::kFixed) { |
| 1767 | TRACE(" input@%d into a fixed phi #%d:%s\n", edge.index(), use->id(), |
| 1768 | use->op()->mnemonic()); |
| 1769 | Node* merge = NodeProperties::GetControlInput(use, 0); |
| 1770 | DCHECK(IrOpcode::IsMergeOpcode(merge->opcode()))((void) 0); |
| 1771 | Node* input = NodeProperties::GetControlInput(merge, edge.index()); |
| 1772 | return FindPredecessorBlock(input); |
| 1773 | } |
| 1774 | } else if (IrOpcode::IsMergeOpcode(use->opcode())) { |
| 1775 | // If the use is from a fixed (i.e. non-floating) merge, we use the |
| 1776 | // predecessor block of the current input to the merge. |
| 1777 | if (scheduler_->GetPlacement(use) == Scheduler::kFixed) { |
| 1778 | TRACE(" input@%d into a fixed merge #%d:%s\n", edge.index(), use->id(), |
| 1779 | use->op()->mnemonic()); |
| 1780 | return FindPredecessorBlock(edge.to()); |
| 1781 | } |
| 1782 | } |
| 1783 | BasicBlock* result = schedule_->block(use); |
| 1784 | if (result == nullptr) return nullptr; |
| 1785 | TRACE(" must dominate use #%d:%s in id:%d\n", use->id(), |
| 1786 | use->op()->mnemonic(), result->id().ToInt()); |
| 1787 | return result; |
| 1788 | } |
| 1789 | |
| 1790 | void ScheduleFloatingControl(BasicBlock* block, Node* node) { |
| 1791 | scheduler_->FuseFloatingControl(block, node); |
| 1792 | } |
| 1793 | |
| 1794 | void ScheduleRegion(BasicBlock* block, Node* region_end) { |
| 1795 | // We only allow regions of instructions connected into a linear |
| 1796 | // effect chain. The only value allowed to be produced by a node |
| 1797 | // in the chain must be the value consumed by the FinishRegion node. |
| 1798 | |
| 1799 | // We schedule back to front; we first schedule FinishRegion. |
| 1800 | CHECK_EQ(IrOpcode::kFinishRegion, region_end->opcode())do { bool _cmp = ::v8::base::CmpEQImpl< typename ::v8::base ::pass_value_or_ref<decltype(IrOpcode::kFinishRegion)>:: type, typename ::v8::base::pass_value_or_ref<decltype(region_end ->opcode())>::type>((IrOpcode::kFinishRegion), (region_end ->opcode())); do { if ((__builtin_expect(!!(!(_cmp)), 0))) { V8_Fatal("Check failed: %s.", "IrOpcode::kFinishRegion" " " "==" " " "region_end->opcode()"); } } while (false); } while (false); |
| 1801 | ScheduleNode(block, region_end); |
| 1802 | |
| 1803 | // Schedule the chain. |
| 1804 | Node* node = NodeProperties::GetEffectInput(region_end); |
| 1805 | while (node->opcode() != IrOpcode::kBeginRegion) { |
| 1806 | DCHECK_EQ(0, scheduler_->GetData(node)->unscheduled_count_)((void) 0); |
| 1807 | DCHECK_EQ(1, node->op()->EffectInputCount())((void) 0); |
| 1808 | DCHECK_EQ(1, node->op()->EffectOutputCount())((void) 0); |
| 1809 | DCHECK_EQ(0, node->op()->ControlOutputCount())((void) 0); |
| 1810 | // The value output (if there is any) must be consumed |
| 1811 | // by the EndRegion node. |
| 1812 | DCHECK(node->op()->ValueOutputCount() == 0 ||((void) 0) |
| 1813 | node == region_end->InputAt(0))((void) 0); |
| 1814 | ScheduleNode(block, node); |
| 1815 | node = NodeProperties::GetEffectInput(node); |
| 1816 | } |
| 1817 | // Schedule the BeginRegion node. |
| 1818 | DCHECK_EQ(0, scheduler_->GetData(node)->unscheduled_count_)((void) 0); |
| 1819 | ScheduleNode(block, node); |
| 1820 | } |
| 1821 | |
| 1822 | void ScheduleNode(BasicBlock* block, Node* node) { |
| 1823 | schedule_->PlanNode(block, node); |
| 1824 | size_t block_id = block->id().ToSize(); |
| 1825 | if (!scheduler_->scheduled_nodes_[block_id]) { |
| 1826 | scheduler_->scheduled_nodes_[block_id] = zone_->New<NodeVector>(zone_); |
| 1827 | } |
| 1828 | scheduler_->scheduled_nodes_[block_id]->push_back(node); |
| 1829 | scheduler_->UpdatePlacement(node, Scheduler::kScheduled); |
| 1830 | } |
| 1831 | |
| 1832 | Node* CloneNode(Node* node) { |
| 1833 | int const input_count = node->InputCount(); |
| 1834 | base::Optional<int> coupled_control_edge = |
| 1835 | scheduler_->GetCoupledControlEdge(node); |
| 1836 | for (int index = 0; index < input_count; ++index) { |
| 1837 | if (index != coupled_control_edge) { |
| 1838 | Node* const input = node->InputAt(index); |
| 1839 | scheduler_->IncrementUnscheduledUseCount(input, node); |
| 1840 | } |
| 1841 | } |
| 1842 | Node* const copy = scheduler_->graph_->CloneNode(node); |
| 1843 | TRACE(("clone #%d:%s -> #%d\n"), node->id(), node->op()->mnemonic(), |
| 1844 | copy->id()); |
| 1845 | scheduler_->node_data_.resize(copy->id() + 1, |
| 1846 | scheduler_->DefaultSchedulerData()); |
| 1847 | scheduler_->node_data_[copy->id()] = scheduler_->node_data_[node->id()]; |
| 1848 | return copy; |
| 1849 | } |
| 1850 | |
| 1851 | Zone* zone_; |
| 1852 | Scheduler* scheduler_; |
| 1853 | Schedule* schedule_; |
| 1854 | BoolVector marked_; |
| 1855 | ZoneDeque<BasicBlock*> marking_queue_; |
| 1856 | }; |
| 1857 | |
| 1858 | |
| 1859 | void Scheduler::ScheduleLate() { |
| 1860 | TRACE("--- SCHEDULE LATE ------------------------------------------\n"); |
| 1861 | if (FLAG_trace_turbo_scheduler) { |
| 1862 | TRACE("roots: "); |
| 1863 | for (Node* node : schedule_root_nodes_) { |
| 1864 | TRACE("#%d:%s ", node->id(), node->op()->mnemonic()); |
| 1865 | } |
| 1866 | TRACE("\n"); |
| 1867 | } |
| 1868 | |
| 1869 | // Schedule: Places nodes in dominator block of all their uses. |
| 1870 | ScheduleLateNodeVisitor schedule_late_visitor(zone_, this); |
| 1871 | schedule_late_visitor.Run(&schedule_root_nodes_); |
| 1872 | } |
| 1873 | |
| 1874 | |
| 1875 | // ----------------------------------------------------------------------------- |
| 1876 | // Phase 6: Seal the final schedule. |
| 1877 | |
| 1878 | |
| 1879 | void Scheduler::SealFinalSchedule() { |
| 1880 | TRACE("--- SEAL FINAL SCHEDULE ------------------------------------\n"); |
| 1881 | |
| 1882 | // Serialize the assembly order and reverse-post-order numbering. |
| 1883 | special_rpo_->SerializeRPOIntoSchedule(); |
| 1884 | special_rpo_->PrintAndVerifySpecialRPO(); |
| 1885 | |
| 1886 | // Add collected nodes for basic blocks to their blocks in the right order. |
| 1887 | int block_num = 0; |
| 1888 | for (NodeVector* nodes : scheduled_nodes_) { |
| 1889 | BasicBlock::Id id = BasicBlock::Id::FromInt(block_num++); |
| 1890 | BasicBlock* block = schedule_->GetBlockById(id); |
| 1891 | if (nodes) { |
| 1892 | for (Node* node : base::Reversed(*nodes)) { |
| 1893 | schedule_->AddNode(block, node); |
| 1894 | } |
| 1895 | } |
| 1896 | } |
| 1897 | } |
| 1898 | |
| 1899 | |
| 1900 | // ----------------------------------------------------------------------------- |
| 1901 | |
| 1902 | |
| 1903 | void Scheduler::FuseFloatingControl(BasicBlock* block, Node* node) { |
| 1904 | TRACE("--- FUSE FLOATING CONTROL ----------------------------------\n"); |
| 1905 | if (FLAG_trace_turbo_scheduler) { |
| 1906 | StdoutStream{} << "Schedule before control flow fusion:\n" << *schedule_; |
| 1907 | } |
| 1908 | |
| 1909 | // Iterate on phase 1: Build control-flow graph. |
| 1910 | control_flow_builder_->Run(block, node); |
| 1911 | |
| 1912 | // Iterate on phase 2: Compute special RPO and dominator tree. |
| 1913 | special_rpo_->UpdateSpecialRPO(block, schedule_->block(node)); |
| 1914 | // TODO(turbofan): Currently "iterate on" means "re-run". Fix that. |
| 1915 | for (BasicBlock* b = block->rpo_next(); b != nullptr; b = b->rpo_next()) { |
| 1916 | b->set_dominator_depth(-1); |
| 1917 | b->set_dominator(nullptr); |
| 1918 | } |
| 1919 | PropagateImmediateDominators(block->rpo_next()); |
| 1920 | |
| 1921 | // Iterate on phase 4: Schedule nodes early. |
| 1922 | // TODO(turbofan): The following loop gathering the propagation roots is a |
| 1923 | // temporary solution and should be merged into the rest of the scheduler as |
| 1924 | // soon as the approach settled for all floating loops. |
| 1925 | NodeVector propagation_roots(control_flow_builder_->control_); |
| 1926 | for (Node* control : control_flow_builder_->control_) { |
| 1927 | for (Node* use : control->uses()) { |
| 1928 | if (NodeProperties::IsPhi(use) && IsLive(use)) { |
| 1929 | propagation_roots.push_back(use); |
| 1930 | } |
| 1931 | } |
| 1932 | } |
| 1933 | if (FLAG_trace_turbo_scheduler) { |
| 1934 | TRACE("propagation roots: "); |
| 1935 | for (Node* r : propagation_roots) { |
| 1936 | TRACE("#%d:%s ", r->id(), r->op()->mnemonic()); |
| 1937 | } |
| 1938 | TRACE("\n"); |
| 1939 | } |
| 1940 | ScheduleEarlyNodeVisitor schedule_early_visitor(zone_, this); |
| 1941 | schedule_early_visitor.Run(&propagation_roots); |
| 1942 | |
| 1943 | // Move previously planned nodes. |
| 1944 | // TODO(turbofan): Improve that by supporting bulk moves. |
| 1945 | scheduled_nodes_.resize(schedule_->BasicBlockCount()); |
| 1946 | MovePlannedNodes(block, schedule_->block(node)); |
| 1947 | |
| 1948 | if (FLAG_trace_turbo_scheduler) { |
| 1949 | StdoutStream{} << "Schedule after control flow fusion:\n" << *schedule_; |
| 1950 | } |
| 1951 | } |
| 1952 | |
| 1953 | |
| 1954 | void Scheduler::MovePlannedNodes(BasicBlock* from, BasicBlock* to) { |
| 1955 | TRACE("Move planned nodes from id:%d to id:%d\n", from->id().ToInt(), |
| 1956 | to->id().ToInt()); |
| 1957 | NodeVector* from_nodes = scheduled_nodes_[from->id().ToSize()]; |
| 1958 | NodeVector* to_nodes = scheduled_nodes_[to->id().ToSize()]; |
| 1959 | if (!from_nodes) return; |
| 1960 | |
| 1961 | for (Node* const node : *from_nodes) { |
| 1962 | schedule_->SetBlockForNode(to, node); |
| 1963 | } |
| 1964 | if (to_nodes) { |
| 1965 | to_nodes->insert(to_nodes->end(), from_nodes->begin(), from_nodes->end()); |
| 1966 | from_nodes->clear(); |
| 1967 | } else { |
| 1968 | std::swap(scheduled_nodes_[from->id().ToSize()], |
| 1969 | scheduled_nodes_[to->id().ToSize()]); |
| 1970 | } |
| 1971 | } |
| 1972 | |
| 1973 | #undef TRACE |
| 1974 | |
| 1975 | } // namespace compiler |
| 1976 | } // namespace internal |
| 1977 | } // namespace v8 |