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| 1 // Copyright (c) 2013, the Dart project authors. Please see the AUTHORS file | |
| 2 // for details. All rights reserved. Use of this source code is governed by a | |
| 3 // BSD-style license that can be found in the LICENSE file. | |
| 4 | |
| 5 // IrNodes are kept in a separate library to have precise control over their | |
| 6 // dependencies on other parts of the system. | |
| 7 library dart2js.ir_nodes; | |
| 8 | |
| 9 import '../constants/expressions.dart'; | |
| 10 import '../constants/values.dart' as values show ConstantValue; | |
| 11 import '../dart2jslib.dart' as dart2js show invariant; | |
| 12 import '../elements/elements.dart'; | |
| 13 import '../universe/universe.dart' show Selector, SelectorKind; | |
| 14 import '../dart_types.dart' show DartType, GenericType; | |
| 15 | |
| 16 abstract class Node { | |
| 17 static int hashCount = 0; | |
| 18 final int hashCode = hashCount = (hashCount + 1) & 0x3fffffff; | |
| 19 | |
| 20 /// A pointer to the parent node. Is null until set by optimization passes. | |
| 21 Node parent; | |
| 22 | |
| 23 accept(Visitor visitor); | |
| 24 } | |
| 25 | |
| 26 abstract class Expression extends Node { | |
| 27 Expression plug(Expression expr) => throw 'impossible'; | |
| 28 } | |
| 29 | |
| 30 /// The base class of things that variables can refer to: primitives, | |
| 31 /// continuations, function and continuation parameters, etc. | |
| 32 abstract class Definition extends Node { | |
| 33 // The head of a linked-list of occurrences, in no particular order. | |
| 34 Reference firstRef = null; | |
| 35 | |
| 36 bool get hasAtMostOneUse => firstRef == null || firstRef.next == null; | |
| 37 bool get hasExactlyOneUse => firstRef != null && firstRef.next == null; | |
| 38 bool get hasAtLeastOneUse => firstRef != null; | |
| 39 bool get hasMultipleUses => !hasAtMostOneUse; | |
| 40 | |
| 41 void substituteFor(Definition other) { | |
| 42 if (other.firstRef == null) return; | |
| 43 Reference previous, current = other.firstRef; | |
| 44 do { | |
| 45 current.definition = this; | |
| 46 previous = current; | |
| 47 current = current.next; | |
| 48 } while (current != null); | |
| 49 previous.next = firstRef; | |
| 50 if (firstRef != null) firstRef.previous = previous; | |
| 51 firstRef = other.firstRef; | |
| 52 } | |
| 53 } | |
| 54 | |
| 55 /// An expression that cannot throw or diverge and has no side-effects. | |
| 56 /// All primitives are named using the identity of the [Primitive] object. | |
| 57 /// | |
| 58 /// Primitives may allocate objects, this is not considered side-effect here. | |
| 59 /// | |
| 60 /// Although primitives may not mutate state, they may depend on state. | |
| 61 abstract class Primitive extends Definition { | |
| 62 /// The [VariableElement] or [ParameterElement] from which the primitive | |
| 63 /// binding originated. | |
| 64 Element hint; | |
| 65 | |
| 66 /// Register in which the variable binding this primitive can be allocated. | |
| 67 /// Separate register spaces are used for primitives with different [element]. | |
| 68 /// Assigned by [RegisterAllocator], is null before that phase. | |
| 69 int registerIndex; | |
| 70 | |
| 71 /// Use the given element as a hint for naming this primitive. | |
| 72 /// | |
| 73 /// Has no effect if this primitive already has a non-null [element]. | |
| 74 void useElementAsHint(Element hint) { | |
| 75 if (this.hint == null) { | |
| 76 this.hint = hint; | |
| 77 } | |
| 78 } | |
| 79 } | |
| 80 | |
| 81 /// Operands to invocations and primitives are always variables. They point to | |
| 82 /// their definition and are doubly-linked into a list of occurrences. | |
| 83 class Reference { | |
| 84 Definition definition; | |
| 85 Reference previous = null; | |
| 86 Reference next = null; | |
| 87 | |
| 88 /// A pointer to the parent node. Is null until set by optimization passes. | |
| 89 Node parent; | |
| 90 | |
| 91 Reference(this.definition) { | |
| 92 next = definition.firstRef; | |
| 93 if (next != null) next.previous = this; | |
| 94 definition.firstRef = this; | |
| 95 } | |
| 96 | |
| 97 /// Unlinks this reference from the list of occurrences. | |
| 98 void unlink() { | |
| 99 if (previous == null) { | |
| 100 assert(definition.firstRef == this); | |
| 101 definition.firstRef = next; | |
| 102 } else { | |
| 103 previous.next = next; | |
| 104 } | |
| 105 if (next != null) next.previous = previous; | |
| 106 } | |
| 107 } | |
| 108 | |
| 109 /// Binding a value (primitive or constant): 'let val x = V in E'. The bound | |
| 110 /// value is in scope in the body. | |
| 111 /// During one-pass construction a LetVal with an empty body is used to | |
| 112 /// represent one-level context 'let val x = V in []'. | |
| 113 class LetPrim extends Expression implements InteriorNode { | |
| 114 final Primitive primitive; | |
| 115 Expression body = null; | |
| 116 | |
| 117 LetPrim(this.primitive); | |
| 118 | |
| 119 Expression plug(Expression expr) { | |
| 120 assert(body == null); | |
| 121 return body = expr; | |
| 122 } | |
| 123 | |
| 124 accept(Visitor visitor) => visitor.visitLetPrim(this); | |
| 125 } | |
| 126 | |
| 127 | |
| 128 /// Binding a continuation: 'let cont k(v) = E in E'. The bound continuation | |
| 129 /// is in scope in the body and the continuation parameter is in scope in the | |
| 130 /// continuation body. | |
| 131 /// During one-pass construction a LetCont with an empty continuation body is | |
| 132 /// used to represent the one-level context 'let cont k(v) = [] in E'. | |
| 133 class LetCont extends Expression implements InteriorNode { | |
| 134 Continuation continuation; | |
| 135 Expression body; | |
| 136 | |
| 137 LetCont(this.continuation, this.body); | |
| 138 | |
| 139 Expression plug(Expression expr) { | |
| 140 assert(continuation != null && continuation.body == null); | |
| 141 return continuation.body = expr; | |
| 142 } | |
| 143 | |
| 144 accept(Visitor visitor) => visitor.visitLetCont(this); | |
| 145 } | |
| 146 | |
| 147 abstract class Invoke { | |
| 148 Selector get selector; | |
| 149 List<Reference> get arguments; | |
| 150 } | |
| 151 | |
| 152 /// Represents a node with a child node, which can be accessed through the | |
| 153 /// `body` member. A typical usage is when removing a node from the CPS graph: | |
| 154 /// | |
| 155 /// Node child = node.body; | |
| 156 /// InteriorNode parent = node.parent; | |
| 157 /// | |
| 158 /// child.parent = parent; | |
| 159 /// parent.body = child; | |
| 160 abstract class InteriorNode implements Node { | |
| 161 Expression body; | |
| 162 } | |
| 163 | |
| 164 /// Invoke a static function or static field getter/setter. | |
| 165 class InvokeStatic extends Expression implements Invoke { | |
| 166 /// [FunctionElement] or [FieldElement]. | |
| 167 final Entity target; | |
| 168 | |
| 169 /** | |
| 170 * The selector encodes how the function is invoked: number of positional | |
| 171 * arguments, names used in named arguments. This information is required | |
| 172 * to build the [StaticCallSiteTypeInformation] for the inference graph. | |
| 173 */ | |
| 174 final Selector selector; | |
| 175 | |
| 176 final Reference continuation; | |
| 177 final List<Reference> arguments; | |
| 178 | |
| 179 InvokeStatic(this.target, this.selector, Continuation cont, | |
| 180 List<Definition> args) | |
| 181 : continuation = new Reference(cont), | |
| 182 arguments = _referenceList(args) { | |
| 183 assert(target is ErroneousElement || selector.name == target.name); | |
| 184 } | |
| 185 | |
| 186 accept(Visitor visitor) => visitor.visitInvokeStatic(this); | |
| 187 } | |
| 188 | |
| 189 /// Invoke a method, operator, getter, setter, or index getter/setter. | |
| 190 /// Converting a method to a function object is treated as a getter invocation. | |
| 191 class InvokeMethod extends Expression implements Invoke { | |
| 192 final Reference receiver; | |
| 193 final Selector selector; | |
| 194 final Reference continuation; | |
| 195 final List<Reference> arguments; | |
| 196 | |
| 197 InvokeMethod(Definition receiver, | |
| 198 this.selector, | |
| 199 Continuation cont, | |
| 200 List<Definition> args) | |
| 201 : receiver = new Reference(receiver), | |
| 202 continuation = new Reference(cont), | |
| 203 arguments = _referenceList(args) { | |
| 204 assert(selector != null); | |
| 205 assert(selector.kind == SelectorKind.CALL || | |
| 206 selector.kind == SelectorKind.OPERATOR || | |
| 207 (selector.kind == SelectorKind.GETTER && arguments.isEmpty) || | |
| 208 (selector.kind == SelectorKind.SETTER && arguments.length == 1) || | |
| 209 (selector.kind == SelectorKind.INDEX && arguments.length == 1) || | |
| 210 (selector.kind == SelectorKind.INDEX && arguments.length == 2)); | |
| 211 } | |
| 212 | |
| 213 accept(Visitor visitor) => visitor.visitInvokeMethod(this); | |
| 214 } | |
| 215 | |
| 216 /// Invoke a method, operator, getter, setter, or index getter/setter from the | |
| 217 /// super class in tail position. | |
| 218 class InvokeSuperMethod extends Expression implements Invoke { | |
| 219 final Selector selector; | |
| 220 final Reference continuation; | |
| 221 final List<Reference> arguments; | |
| 222 | |
| 223 InvokeSuperMethod(this.selector, | |
| 224 Continuation cont, | |
| 225 List<Definition> args) | |
| 226 : continuation = new Reference(cont), | |
| 227 arguments = _referenceList(args) { | |
| 228 assert(selector != null); | |
| 229 assert(selector.kind == SelectorKind.CALL || | |
| 230 selector.kind == SelectorKind.OPERATOR || | |
| 231 (selector.kind == SelectorKind.GETTER && arguments.isEmpty) || | |
| 232 (selector.kind == SelectorKind.SETTER && arguments.length == 1) || | |
| 233 (selector.kind == SelectorKind.INDEX && arguments.length == 1) || | |
| 234 (selector.kind == SelectorKind.INDEX && arguments.length == 2)); | |
| 235 } | |
| 236 | |
| 237 accept(Visitor visitor) => visitor.visitInvokeSuperMethod(this); | |
| 238 } | |
| 239 | |
| 240 /// Non-const call to a constructor. The [target] may be a generative | |
| 241 /// constructor, factory, or redirecting factory. | |
| 242 class InvokeConstructor extends Expression implements Invoke { | |
| 243 final DartType type; | |
| 244 final FunctionElement target; | |
| 245 final Reference continuation; | |
| 246 final List<Reference> arguments; | |
| 247 final Selector selector; | |
| 248 | |
| 249 /// The class being instantiated. This is the same as `target.enclosingClass` | |
| 250 /// and `type.element`. | |
| 251 ClassElement get targetClass => target.enclosingElement; | |
| 252 | |
| 253 /// True if this is an invocation of a factory constructor. | |
| 254 bool get isFactory => target.isFactoryConstructor; | |
| 255 | |
| 256 InvokeConstructor(this.type, | |
| 257 this.target, | |
| 258 this.selector, | |
| 259 Continuation cont, | |
| 260 List<Definition> args) | |
| 261 : continuation = new Reference(cont), | |
| 262 arguments = _referenceList(args) { | |
| 263 assert(dart2js.invariant(target, | |
| 264 target.isErroneous || target.isConstructor, | |
| 265 message: "Constructor invocation target is not a constructor: " | |
| 266 "$target.")); | |
| 267 assert(dart2js.invariant(target, | |
| 268 target.isErroneous || | |
| 269 type.isDynamic || | |
| 270 type.element == target.enclosingClass.declaration, | |
| 271 message: "Constructor invocation type ${type} does not match enclosing " | |
| 272 "class of target ${target}.")); | |
| 273 } | |
| 274 | |
| 275 accept(Visitor visitor) => visitor.visitInvokeConstructor(this); | |
| 276 } | |
| 277 | |
| 278 /// "as" casts and "is" checks. | |
| 279 // We might want to turn "is"-checks into a [Primitive] as it can never diverge. | |
| 280 // But then we need to special-case for is-checks with an erroneous .type as | |
| 281 // these will throw. | |
| 282 class TypeOperator extends Expression { | |
| 283 final Reference receiver; | |
| 284 final DartType type; | |
| 285 final Reference continuation; | |
| 286 final String operator; | |
| 287 | |
| 288 TypeOperator(this.operator, | |
| 289 Primitive receiver, | |
| 290 this.type, | |
| 291 Continuation cont) | |
| 292 : this.receiver = new Reference(receiver), | |
| 293 this.continuation = new Reference(cont) { | |
| 294 assert(operator == "is" || operator == "as"); | |
| 295 } | |
| 296 | |
| 297 accept(Visitor visitor) => visitor.visitTypeOperator(this); | |
| 298 } | |
| 299 | |
| 300 /// Invoke [toString] on each argument and concatenate the results. | |
| 301 class ConcatenateStrings extends Expression { | |
| 302 final Reference continuation; | |
| 303 final List<Reference> arguments; | |
| 304 | |
| 305 ConcatenateStrings(Continuation cont, List<Definition> args) | |
| 306 : continuation = new Reference(cont), | |
| 307 arguments = _referenceList(args); | |
| 308 | |
| 309 accept(Visitor visitor) => visitor.visitConcatenateStrings(this); | |
| 310 } | |
| 311 | |
| 312 /// Gets the value from a closure variable. The identity of the variable is | |
| 313 /// determined by a [Local]. | |
| 314 /// | |
| 315 /// Closure variables can be seen as ref cells that are not first-class values. | |
| 316 /// A [LetPrim] with a [GetClosureVariable] can then be seen as: | |
| 317 /// | |
| 318 /// let prim p = ![variable] in [body] | |
| 319 /// | |
| 320 class GetClosureVariable extends Primitive { | |
| 321 final Local variable; | |
| 322 | |
| 323 GetClosureVariable(this.variable) { | |
| 324 assert(variable != null); | |
| 325 } | |
| 326 | |
| 327 accept(Visitor visitor) => visitor.visitGetClosureVariable(this); | |
| 328 } | |
| 329 | |
| 330 /// Assign or declare a closure variable. The identity of the variable is | |
| 331 /// determined by a [Local]. | |
| 332 /// | |
| 333 /// Closure variables can be seen as ref cells that are not first-class values. | |
| 334 /// If [isDeclaration], this can seen as a let binding: | |
| 335 /// | |
| 336 /// let [variable] = ref [value] in [body] | |
| 337 /// | |
| 338 /// And otherwise, it can be seen as a dereferencing assignment: | |
| 339 /// | |
| 340 /// { ![variable] := [value]; [body] } | |
| 341 /// | |
| 342 /// Closure variables without a declaring [SetClosureVariable] are implicitly | |
| 343 /// declared at the entry to the [variable]'s enclosing function. | |
| 344 class SetClosureVariable extends Expression implements InteriorNode { | |
| 345 final Local variable; | |
| 346 final Reference value; | |
| 347 Expression body; | |
| 348 | |
| 349 /// If true, this declares a new copy of the closure variable. If so, all | |
| 350 /// uses of the closure variable must occur in the [body]. | |
| 351 /// | |
| 352 /// There can be at most one declaration per closure variable. If there is no | |
| 353 /// declaration, only one copy exists (per function execution). It is best to | |
| 354 /// avoid declaring closure variables if it is not necessary. | |
| 355 final bool isDeclaration; | |
| 356 | |
| 357 SetClosureVariable(this.variable, Primitive value, | |
| 358 {this.isDeclaration : false }) | |
| 359 : this.value = new Reference(value) { | |
| 360 assert(variable != null); | |
| 361 } | |
| 362 | |
| 363 accept(Visitor visitor) => visitor.visitSetClosureVariable(this); | |
| 364 | |
| 365 Expression plug(Expression expr) { | |
| 366 assert(body == null); | |
| 367 return body = expr; | |
| 368 } | |
| 369 } | |
| 370 | |
| 371 /// Create a potentially recursive function and store it in a closure variable. | |
| 372 /// The function can access itself using [GetClosureVariable] on [variable]. | |
| 373 /// There must not exist a [SetClosureVariable] to [variable]. | |
| 374 /// | |
| 375 /// This can be seen as a let rec binding: | |
| 376 /// | |
| 377 /// let rec [variable] = [definition] in [body] | |
| 378 /// | |
| 379 class DeclareFunction extends Expression implements InteriorNode { | |
| 380 final Local variable; | |
| 381 final FunctionDefinition definition; | |
| 382 Expression body; | |
| 383 | |
| 384 DeclareFunction(this.variable, this.definition); | |
| 385 | |
| 386 Expression plug(Expression expr) { | |
| 387 assert(body == null); | |
| 388 return body = expr; | |
| 389 } | |
| 390 | |
| 391 accept(Visitor visitor) => visitor.visitDeclareFunction(this); | |
| 392 } | |
| 393 | |
| 394 /// Invoke a continuation in tail position. | |
| 395 class InvokeContinuation extends Expression { | |
| 396 Reference continuation; | |
| 397 List<Reference> arguments; | |
| 398 | |
| 399 // An invocation of a continuation is recursive if it occurs in the body of | |
| 400 // the continuation itself. | |
| 401 bool isRecursive; | |
| 402 | |
| 403 InvokeContinuation(Continuation cont, List<Definition> args, | |
| 404 {recursive: false}) | |
| 405 : continuation = new Reference(cont), | |
| 406 arguments = _referenceList(args), | |
| 407 isRecursive = recursive { | |
| 408 assert(cont.parameters == null || | |
| 409 cont.parameters.length == args.length); | |
| 410 if (recursive) cont.isRecursive = true; | |
| 411 } | |
| 412 | |
| 413 /// A continuation invocation whose target and arguments will be filled | |
| 414 /// in later. | |
| 415 /// | |
| 416 /// Used as a placeholder for a jump whose target is not yet created | |
| 417 /// (e.g., in the translation of break and continue). | |
| 418 InvokeContinuation.uninitialized({recursive: false}) | |
| 419 : continuation = null, | |
| 420 arguments = null, | |
| 421 isRecursive = recursive; | |
| 422 | |
| 423 accept(Visitor visitor) => visitor.visitInvokeContinuation(this); | |
| 424 } | |
| 425 | |
| 426 /// The base class of things which can be tested and branched on. | |
| 427 abstract class Condition extends Node { | |
| 428 } | |
| 429 | |
| 430 class IsTrue extends Condition { | |
| 431 final Reference value; | |
| 432 | |
| 433 IsTrue(Definition val) : value = new Reference(val); | |
| 434 | |
| 435 accept(Visitor visitor) => visitor.visitIsTrue(this); | |
| 436 } | |
| 437 | |
| 438 /// Choose between a pair of continuations based on a condition value. | |
| 439 class Branch extends Expression { | |
| 440 final Condition condition; | |
| 441 final Reference trueContinuation; | |
| 442 final Reference falseContinuation; | |
| 443 | |
| 444 Branch(this.condition, Continuation trueCont, Continuation falseCont) | |
| 445 : trueContinuation = new Reference(trueCont), | |
| 446 falseContinuation = new Reference(falseCont); | |
| 447 | |
| 448 accept(Visitor visitor) => visitor.visitBranch(this); | |
| 449 } | |
| 450 | |
| 451 class Constant extends Primitive { | |
| 452 final ConstantExpression expression; | |
| 453 | |
| 454 Constant(this.expression); | |
| 455 | |
| 456 values.ConstantValue get value => expression.value; | |
| 457 | |
| 458 accept(Visitor visitor) => visitor.visitConstant(this); | |
| 459 } | |
| 460 | |
| 461 class This extends Primitive { | |
| 462 This(); | |
| 463 | |
| 464 accept(Visitor visitor) => visitor.visitThis(this); | |
| 465 } | |
| 466 | |
| 467 /// Reify the given type variable as a [Type]. | |
| 468 /// This depends on the current binding of 'this'. | |
| 469 class ReifyTypeVar extends Primitive { | |
| 470 final TypeVariableElement typeVariable; | |
| 471 | |
| 472 ReifyTypeVar(this.typeVariable); | |
| 473 | |
| 474 values.ConstantValue get constant => null; | |
| 475 | |
| 476 accept(Visitor visitor) => visitor.visitReifyTypeVar(this); | |
| 477 } | |
| 478 | |
| 479 class LiteralList extends Primitive { | |
| 480 /// The List type being created; this is not the type argument. | |
| 481 final GenericType type; | |
| 482 final List<Reference> values; | |
| 483 | |
| 484 LiteralList(this.type, List<Primitive> values) | |
| 485 : this.values = _referenceList(values); | |
| 486 | |
| 487 accept(Visitor visitor) => visitor.visitLiteralList(this); | |
| 488 } | |
| 489 | |
| 490 class LiteralMap extends Primitive { | |
| 491 final GenericType type; | |
| 492 final List<Reference> keys; | |
| 493 final List<Reference> values; | |
| 494 | |
| 495 LiteralMap(this.type, List<Primitive> keys, List<Primitive> values) | |
| 496 : this.keys = _referenceList(keys), | |
| 497 this.values = _referenceList(values); | |
| 498 | |
| 499 accept(Visitor visitor) => visitor.visitLiteralMap(this); | |
| 500 } | |
| 501 | |
| 502 /// Create a non-recursive function. | |
| 503 class CreateFunction extends Primitive { | |
| 504 final FunctionDefinition definition; | |
| 505 | |
| 506 CreateFunction(this.definition); | |
| 507 | |
| 508 accept(Visitor visitor) => visitor.visitCreateFunction(this); | |
| 509 } | |
| 510 | |
| 511 class Parameter extends Primitive { | |
| 512 Parameter(Element element) { | |
| 513 super.hint = element; | |
| 514 } | |
| 515 | |
| 516 accept(Visitor visitor) => visitor.visitParameter(this); | |
| 517 } | |
| 518 | |
| 519 /// Continuations are normally bound by 'let cont'. A continuation with one | |
| 520 /// parameter and no body is used to represent a function's return continuation. | |
| 521 /// The return continuation is bound by the Function, not by 'let cont'. | |
| 522 class Continuation extends Definition implements InteriorNode { | |
| 523 final List<Parameter> parameters; | |
| 524 Expression body = null; | |
| 525 | |
| 526 // A continuation is recursive if it has any recursive invocations. | |
| 527 bool isRecursive = false; | |
| 528 | |
| 529 bool get isReturnContinuation => body == null; | |
| 530 | |
| 531 Continuation(this.parameters); | |
| 532 | |
| 533 Continuation.retrn() : parameters = <Parameter>[new Parameter(null)]; | |
| 534 | |
| 535 accept(Visitor visitor) => visitor.visitContinuation(this); | |
| 536 } | |
| 537 | |
| 538 /// A function definition, consisting of parameters and a body. The parameters | |
| 539 /// include a distinguished continuation parameter. | |
| 540 class FunctionDefinition extends Node implements InteriorNode { | |
| 541 final FunctionElement element; | |
| 542 final Continuation returnContinuation; | |
| 543 final List<Parameter> parameters; | |
| 544 Expression body; | |
| 545 final List<ConstDeclaration> localConstants; | |
| 546 | |
| 547 /// Values for optional parameters. | |
| 548 final List<ConstantExpression> defaultParameterValues; | |
| 549 | |
| 550 FunctionDefinition(this.element, this.returnContinuation, | |
| 551 this.parameters, this.body, this.localConstants, | |
| 552 this.defaultParameterValues); | |
| 553 | |
| 554 FunctionDefinition.abstract(this.element, | |
| 555 this.parameters, | |
| 556 this.defaultParameterValues) | |
| 557 : this.returnContinuation = null, | |
| 558 this.localConstants = const <ConstDeclaration>[]; | |
| 559 | |
| 560 accept(Visitor visitor) => visitor.visitFunctionDefinition(this); | |
| 561 | |
| 562 /// Returns `true` if this function is abstract. | |
| 563 /// | |
| 564 /// If `true`, [body] and [returnContinuation] are `null` and [localConstants] | |
| 565 /// is empty. | |
| 566 bool get isAbstract => body == null; | |
| 567 } | |
| 568 | |
| 569 List<Reference> _referenceList(List<Definition> definitions) { | |
| 570 return definitions.map((e) => new Reference(e)).toList(); | |
| 571 } | |
| 572 | |
| 573 abstract class Visitor<T> { | |
| 574 T visit(Node node) => node.accept(this); | |
| 575 // Abstract classes. | |
| 576 T visitNode(Node node) => null; | |
| 577 T visitExpression(Expression node) => visitNode(node); | |
| 578 T visitDefinition(Definition node) => visitNode(node); | |
| 579 T visitPrimitive(Primitive node) => visitDefinition(node); | |
| 580 T visitCondition(Condition node) => visitNode(node); | |
| 581 | |
| 582 // Concrete classes. | |
| 583 T visitFunctionDefinition(FunctionDefinition node) => visitNode(node); | |
| 584 | |
| 585 // Expressions. | |
| 586 T visitLetPrim(LetPrim node) => visitExpression(node); | |
| 587 T visitLetCont(LetCont node) => visitExpression(node); | |
| 588 T visitInvokeStatic(InvokeStatic node) => visitExpression(node); | |
| 589 T visitInvokeContinuation(InvokeContinuation node) => visitExpression(node); | |
| 590 T visitInvokeMethod(InvokeMethod node) => visitExpression(node); | |
| 591 T visitInvokeSuperMethod(InvokeSuperMethod node) => visitExpression(node); | |
| 592 T visitInvokeConstructor(InvokeConstructor node) => visitExpression(node); | |
| 593 T visitConcatenateStrings(ConcatenateStrings node) => visitExpression(node); | |
| 594 T visitBranch(Branch node) => visitExpression(node); | |
| 595 T visitTypeOperator(TypeOperator node) => visitExpression(node); | |
| 596 T visitSetClosureVariable(SetClosureVariable node) => visitExpression(node); | |
| 597 T visitDeclareFunction(DeclareFunction node) => visitExpression(node); | |
| 598 | |
| 599 // Definitions. | |
| 600 T visitLiteralList(LiteralList node) => visitPrimitive(node); | |
| 601 T visitLiteralMap(LiteralMap node) => visitPrimitive(node); | |
| 602 T visitConstant(Constant node) => visitPrimitive(node); | |
| 603 T visitThis(This node) => visitPrimitive(node); | |
| 604 T visitReifyTypeVar(ReifyTypeVar node) => visitPrimitive(node); | |
| 605 T visitCreateFunction(CreateFunction node) => visitPrimitive(node); | |
| 606 T visitGetClosureVariable(GetClosureVariable node) => visitPrimitive(node); | |
| 607 T visitParameter(Parameter node) => visitPrimitive(node); | |
| 608 T visitContinuation(Continuation node) => visitDefinition(node); | |
| 609 | |
| 610 // Conditions. | |
| 611 T visitIsTrue(IsTrue node) => visitCondition(node); | |
| 612 } | |
| 613 | |
| 614 /// Recursively visits the entire CPS term, and calls abstract `process*` | |
| 615 /// (i.e. `processLetPrim`) functions in pre-order. | |
| 616 abstract class RecursiveVisitor extends Visitor { | |
| 617 // Ensures that RecursiveVisitor contains overrides for all relevant nodes. | |
| 618 // As a rule of thumb, nodes with structure to traverse should be overridden | |
| 619 // with the appropriate visits in this class (for example, visitLetCont), | |
| 620 // while leaving other nodes for subclasses (i.e., visitLiteralList). | |
| 621 visitNode(Node node) { | |
| 622 throw "RecursiveVisitor is stale, add missing visit overrides"; | |
| 623 } | |
| 624 | |
| 625 processReference(Reference ref) {} | |
| 626 | |
| 627 processFunctionDefinition(FunctionDefinition node) {} | |
| 628 visitFunctionDefinition(FunctionDefinition node) { | |
| 629 processFunctionDefinition(node); | |
| 630 node.parameters.forEach(visitParameter); | |
| 631 visit(node.body); | |
| 632 } | |
| 633 | |
| 634 // Expressions. | |
| 635 | |
| 636 processLetPrim(LetPrim node) {} | |
| 637 visitLetPrim(LetPrim node) { | |
| 638 processLetPrim(node); | |
| 639 visit(node.primitive); | |
| 640 visit(node.body); | |
| 641 } | |
| 642 | |
| 643 processLetCont(LetCont node) {} | |
| 644 visitLetCont(LetCont node) { | |
| 645 processLetCont(node); | |
| 646 visit(node.continuation); | |
| 647 visit(node.body); | |
| 648 } | |
| 649 | |
| 650 processInvokeStatic(InvokeStatic node) {} | |
| 651 visitInvokeStatic(InvokeStatic node) { | |
| 652 processInvokeStatic(node); | |
| 653 processReference(node.continuation); | |
| 654 node.arguments.forEach(processReference); | |
| 655 } | |
| 656 | |
| 657 processInvokeContinuation(InvokeContinuation node) {} | |
| 658 visitInvokeContinuation(InvokeContinuation node) { | |
| 659 processInvokeContinuation(node); | |
| 660 processReference(node.continuation); | |
| 661 node.arguments.forEach(processReference); | |
| 662 } | |
| 663 | |
| 664 processInvokeMethod(InvokeMethod node) {} | |
| 665 visitInvokeMethod(InvokeMethod node) { | |
| 666 processInvokeMethod(node); | |
| 667 processReference(node.receiver); | |
| 668 processReference(node.continuation); | |
| 669 node.arguments.forEach(processReference); | |
| 670 } | |
| 671 | |
| 672 processInvokeSuperMethod(InvokeSuperMethod node) {} | |
| 673 visitInvokeSuperMethod(InvokeSuperMethod node) { | |
| 674 processInvokeSuperMethod(node); | |
| 675 processReference(node.continuation); | |
| 676 node.arguments.forEach(processReference); | |
| 677 } | |
| 678 | |
| 679 processInvokeConstructor(InvokeConstructor node) {} | |
| 680 visitInvokeConstructor(InvokeConstructor node) { | |
| 681 processInvokeConstructor(node); | |
| 682 processReference(node.continuation); | |
| 683 node.arguments.forEach(processReference); | |
| 684 } | |
| 685 | |
| 686 processConcatenateStrings(ConcatenateStrings node) {} | |
| 687 visitConcatenateStrings(ConcatenateStrings node) { | |
| 688 processConcatenateStrings(node); | |
| 689 processReference(node.continuation); | |
| 690 node.arguments.forEach(processReference); | |
| 691 } | |
| 692 | |
| 693 | |
| 694 processBranch(Branch node) {} | |
| 695 visitBranch(Branch node) { | |
| 696 processBranch(node); | |
| 697 processReference(node.trueContinuation); | |
| 698 processReference(node.falseContinuation); | |
| 699 visit(node.condition); | |
| 700 } | |
| 701 | |
| 702 processTypeOperator(TypeOperator node) {} | |
| 703 visitTypeOperator(TypeOperator node) { | |
| 704 processTypeOperator(node); | |
| 705 processReference(node.continuation); | |
| 706 processReference(node.receiver); | |
| 707 } | |
| 708 | |
| 709 processSetClosureVariable(SetClosureVariable node) {} | |
| 710 visitSetClosureVariable(SetClosureVariable node) { | |
| 711 processSetClosureVariable(node); | |
| 712 processReference(node.value); | |
| 713 visit(node.body); | |
| 714 } | |
| 715 | |
| 716 processDeclareFunction(DeclareFunction node) {} | |
| 717 visitDeclareFunction(DeclareFunction node) { | |
| 718 processDeclareFunction(node); | |
| 719 visit(node.definition); | |
| 720 visit(node.body); | |
| 721 } | |
| 722 | |
| 723 // Definitions. | |
| 724 | |
| 725 processLiteralList(LiteralList node) {} | |
| 726 visitLiteralList(LiteralList node) { | |
| 727 processLiteralList(node); | |
| 728 node.values.forEach(processReference); | |
| 729 } | |
| 730 | |
| 731 processLiteralMap(LiteralMap node) {} | |
| 732 visitLiteralMap(LiteralMap node) { | |
| 733 processLiteralMap(node); | |
| 734 for (int i = 0; i < node.keys.length; i++) { | |
| 735 processReference(node.keys[i]); | |
| 736 processReference(node.values[i]); | |
| 737 } | |
| 738 } | |
| 739 | |
| 740 processConstant(Constant node) {} | |
| 741 visitConstant(Constant node) => processConstant(node); | |
| 742 | |
| 743 processThis(This node) {} | |
| 744 visitThis(This node) => processThis(node); | |
| 745 | |
| 746 processReifyTypeVar(ReifyTypeVar node) {} | |
| 747 visitReifyTypeVar(ReifyTypeVar node) => processReifyTypeVar(node); | |
| 748 | |
| 749 processCreateFunction(CreateFunction node) {} | |
| 750 visitCreateFunction(CreateFunction node) { | |
| 751 processCreateFunction(node); | |
| 752 visit(node.definition); | |
| 753 } | |
| 754 | |
| 755 processGetClosureVariable(GetClosureVariable node) {} | |
| 756 visitGetClosureVariable(GetClosureVariable node) => | |
| 757 processGetClosureVariable(node); | |
| 758 | |
| 759 processParameter(Parameter node) {} | |
| 760 visitParameter(Parameter node) => processParameter(node); | |
| 761 | |
| 762 processContinuation(Continuation node) {} | |
| 763 visitContinuation(Continuation node) { | |
| 764 processContinuation(node); | |
| 765 node.parameters.forEach(visitParameter); | |
| 766 visit(node.body); | |
| 767 } | |
| 768 | |
| 769 // Conditions. | |
| 770 | |
| 771 processIsTrue(IsTrue node) {} | |
| 772 visitIsTrue(IsTrue node) { | |
| 773 processIsTrue(node); | |
| 774 processReference(node.value); | |
| 775 } | |
| 776 } | |
| 777 | |
| 778 /// Keeps track of currently unused register indices. | |
| 779 class RegisterArray { | |
| 780 int nextIndex = 0; | |
| 781 final List<int> freeStack = <int>[]; | |
| 782 | |
| 783 /// Returns an index that is currently unused. | |
| 784 int makeIndex() { | |
| 785 if (freeStack.isEmpty) { | |
| 786 return nextIndex++; | |
| 787 } else { | |
| 788 return freeStack.removeLast(); | |
| 789 } | |
| 790 } | |
| 791 | |
| 792 void releaseIndex(int index) { | |
| 793 freeStack.add(index); | |
| 794 } | |
| 795 } | |
| 796 | |
| 797 /// Assigns indices to each primitive in the IR such that primitives that are | |
| 798 /// live simultaneously never get assigned the same index. | |
| 799 /// This information is used by the dart tree builder to generate fewer | |
| 800 /// redundant variables. | |
| 801 /// Currently, the liveness analysis is very simple and is often inadequate | |
| 802 /// for removing all of the redundant variables. | |
| 803 class RegisterAllocator extends Visitor { | |
| 804 /// Separate register spaces for each source-level variable/parameter. | |
| 805 /// Note that null is used as key for primitives without elements. | |
| 806 final Map<Element, RegisterArray> elementRegisters = | |
| 807 <Element, RegisterArray>{}; | |
| 808 | |
| 809 RegisterArray getRegisterArray(Element element) { | |
| 810 RegisterArray registers = elementRegisters[element]; | |
| 811 if (registers == null) { | |
| 812 registers = new RegisterArray(); | |
| 813 elementRegisters[element] = registers; | |
| 814 } | |
| 815 return registers; | |
| 816 } | |
| 817 | |
| 818 void allocate(Primitive primitive) { | |
| 819 if (primitive.registerIndex == null) { | |
| 820 primitive.registerIndex = getRegisterArray(primitive.hint).makeIndex(); | |
| 821 } | |
| 822 } | |
| 823 | |
| 824 void release(Primitive primitive) { | |
| 825 // Do not share indices for temporaries as this may obstruct inlining. | |
| 826 if (primitive.hint == null) return; | |
| 827 if (primitive.registerIndex != null) { | |
| 828 getRegisterArray(primitive.hint).releaseIndex(primitive.registerIndex); | |
| 829 } | |
| 830 } | |
| 831 | |
| 832 void visitReference(Reference reference) { | |
| 833 allocate(reference.definition); | |
| 834 } | |
| 835 | |
| 836 void visitFunctionDefinition(FunctionDefinition node) { | |
| 837 if (!node.isAbstract) { | |
| 838 visit(node.body); | |
| 839 } | |
| 840 node.parameters.forEach(allocate); // Assign indices to unused parameters. | |
| 841 elementRegisters.clear(); | |
| 842 } | |
| 843 | |
| 844 void visitLetPrim(LetPrim node) { | |
| 845 visit(node.body); | |
| 846 release(node.primitive); | |
| 847 visit(node.primitive); | |
| 848 } | |
| 849 | |
| 850 void visitLetCont(LetCont node) { | |
| 851 visit(node.continuation); | |
| 852 visit(node.body); | |
| 853 } | |
| 854 | |
| 855 void visitInvokeStatic(InvokeStatic node) { | |
| 856 node.arguments.forEach(visitReference); | |
| 857 } | |
| 858 | |
| 859 void visitInvokeContinuation(InvokeContinuation node) { | |
| 860 node.arguments.forEach(visitReference); | |
| 861 } | |
| 862 | |
| 863 void visitInvokeMethod(InvokeMethod node) { | |
| 864 visitReference(node.receiver); | |
| 865 node.arguments.forEach(visitReference); | |
| 866 } | |
| 867 | |
| 868 void visitInvokeSuperMethod(InvokeSuperMethod node) { | |
| 869 node.arguments.forEach(visitReference); | |
| 870 } | |
| 871 | |
| 872 void visitInvokeConstructor(InvokeConstructor node) { | |
| 873 node.arguments.forEach(visitReference); | |
| 874 } | |
| 875 | |
| 876 void visitConcatenateStrings(ConcatenateStrings node) { | |
| 877 node.arguments.forEach(visitReference); | |
| 878 } | |
| 879 | |
| 880 void visitBranch(Branch node) { | |
| 881 visit(node.condition); | |
| 882 } | |
| 883 | |
| 884 void visitLiteralList(LiteralList node) { | |
| 885 node.values.forEach(visitReference); | |
| 886 } | |
| 887 | |
| 888 void visitLiteralMap(LiteralMap node) { | |
| 889 for (int i = 0; i < node.keys.length; ++i) { | |
| 890 visitReference(node.keys[i]); | |
| 891 visitReference(node.values[i]); | |
| 892 } | |
| 893 } | |
| 894 | |
| 895 void visitTypeOperator(TypeOperator node) { | |
| 896 visitReference(node.receiver); | |
| 897 } | |
| 898 | |
| 899 void visitConstant(Constant node) { | |
| 900 } | |
| 901 | |
| 902 void visitThis(This node) { | |
| 903 } | |
| 904 | |
| 905 void visitReifyTypeVar(ReifyTypeVar node) { | |
| 906 } | |
| 907 | |
| 908 void visitCreateFunction(CreateFunction node) { | |
| 909 new RegisterAllocator().visit(node.definition); | |
| 910 } | |
| 911 | |
| 912 void visitGetClosureVariable(GetClosureVariable node) { | |
| 913 } | |
| 914 | |
| 915 void visitSetClosureVariable(SetClosureVariable node) { | |
| 916 visit(node.body); | |
| 917 visitReference(node.value); | |
| 918 } | |
| 919 | |
| 920 void visitDeclareFunction(DeclareFunction node) { | |
| 921 new RegisterAllocator().visit(node.definition); | |
| 922 visit(node.body); | |
| 923 } | |
| 924 | |
| 925 void visitParameter(Parameter node) { | |
| 926 throw "Parameters should not be visited by RegisterAllocator"; | |
| 927 } | |
| 928 | |
| 929 void visitContinuation(Continuation node) { | |
| 930 visit(node.body); | |
| 931 | |
| 932 // Arguments get allocated left-to-right, so we release parameters | |
| 933 // right-to-left. This increases the likelihood that arguments can be | |
| 934 // transferred without intermediate assignments. | |
| 935 for (int i = node.parameters.length - 1; i >= 0; --i) { | |
| 936 release(node.parameters[i]); | |
| 937 } | |
| 938 } | |
| 939 | |
| 940 void visitIsTrue(IsTrue node) { | |
| 941 visitReference(node.value); | |
| 942 } | |
| 943 | |
| 944 } | |
| 945 | |
| OLD | NEW |
|---|
Chromium Code Reviews
Issue 692513002:
Remove old dart2js code. (Closed)
Base URL: https://dart.googlecode.com/svn/branches/bleeding_edge/dart