Revert "Move dart2js from sdk/lib/_internal/compiler to pkg/compiler"

pkg/compiler/lib/src/ssa/types_propagation.dart

Index: pkg/compiler/lib/src/ssa/types_propagation.dart
diff --git a/pkg/compiler/lib/src/ssa/types_propagation.dart b/pkg/compiler/lib/src/ssa/types_propagation.dart
deleted file mode 100644
index eb21bb402cb70999d5514ab5e0ceea01109835e3..0000000000000000000000000000000000000000
--- a/pkg/compiler/lib/src/ssa/types_propagation.dart
+++ /dev/null
@@ -1,363 +0,0 @@
-// Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
-// for details. All rights reserved. Use of this source code is governed by a
-// BSD-style license that can be found in the LICENSE file.
-
-part of ssa;
-
-class SsaTypePropagator extends HBaseVisitor implements OptimizationPhase {
-  final Map<int, HInstruction> workmap = new Map<int, HInstruction>();
-  final List<int> worklist = new List<int>();
-  final Map<HInstruction, Function> pendingOptimizations =
-      new Map<HInstruction, Function>();
-
-  final Compiler compiler;
-  final ClassWorld classWorld;
-  JavaScriptBackend get backend => compiler.backend;
-  String get name => 'type propagator';
-
-  SsaTypePropagator(Compiler compiler)
-      : this.compiler = compiler,
-        this.classWorld = compiler.world;
-
-  TypeMask computeType(HInstruction instruction) {
-    return instruction.accept(this);
-  }
-
-  // Re-compute and update the type of the instruction. Returns
-  // whether or not the type was changed.
-  bool updateType(HInstruction instruction) {
-    // Compute old and new types.
-    TypeMask oldType = instruction.instructionType;
-    TypeMask newType = computeType(instruction);
-    assert(newType != null);
-    // We unconditionally replace the propagated type with the new type. The
-    // computeType must make sure that we eventually reach a stable state.
-    instruction.instructionType = newType;
-    return oldType != newType;
-  }
-
-  void visitGraph(HGraph graph) {
-    visitDominatorTree(graph);
-    processWorklist();
-  }
-
-  visitBasicBlock(HBasicBlock block) {
-    if (block.isLoopHeader()) {
-      block.forEachPhi((HPhi phi) {
-        // Set the initial type for the phi. We're not using the type
-        // the phi thinks it has because new optimizations may imply
-        // changing it.
-        // In theory we would need to mark
-        // the type of all other incoming edges as "unitialized" and take this
-        // into account when doing the propagation inside the phis. Just
-        // setting the propagated type is however easier.
-        phi.instructionType = phi.inputs[0].instructionType;
-        addToWorkList(phi);
-      });
-    } else {
-      block.forEachPhi((HPhi phi) {
-        if (updateType(phi)) {
-          addDependentInstructionsToWorkList(phi);
-        }
-      });
-    }
-
-    HInstruction instruction = block.first;
-    while (instruction != null) {
-      if (updateType(instruction)) {
-        addDependentInstructionsToWorkList(instruction);
-      }
-      instruction = instruction.next;
-    }
-  }
-
-  void processWorklist() {
-    do {
-      while (!worklist.isEmpty) {
-        int id = worklist.removeLast();
-        HInstruction instruction = workmap[id];
-        assert(instruction != null);
-        workmap.remove(id);
-        if (updateType(instruction)) {
-          addDependentInstructionsToWorkList(instruction);
-        }
-      }
-      // While processing the optimizable arithmetic instructions, we
-      // may discover better type information for dominated users of
-      // replaced operands, so we may need to take another stab at
-      // emptying the worklist afterwards.
-      processPendingOptimizations();
-    } while (!worklist.isEmpty);
-  }
-
-
-  void addToWorkList(HInstruction instruction) {
-    final int id = instruction.id;
-
-    if (!workmap.containsKey(id)) {
-      worklist.add(id);
-      workmap[id] = instruction;
-    }
-  }
-
-  TypeMask visitBinaryArithmetic(HBinaryArithmetic instruction) {
-    HInstruction left = instruction.left;
-    HInstruction right = instruction.right;
-    if (left.isInteger(compiler) && right.isInteger(compiler)) {
-      return backend.intType;
-    }
-    if (left.isDouble(compiler)) return backend.doubleType;
-    return backend.numType;
-  }
-
-  TypeMask checkPositiveInteger(HBinaryArithmetic instruction) {
-    HInstruction left = instruction.left;
-    HInstruction right = instruction.right;
-    if (left.isPositiveInteger(compiler) && right.isPositiveInteger(compiler)) {
-      return backend.positiveIntType;
-    }
-    return visitBinaryArithmetic(instruction);
-  }
-
-  TypeMask visitMultiply(HMultiply instruction) {
-    return checkPositiveInteger(instruction);
-  }
-
-  TypeMask visitAdd(HAdd instruction) {
-    return checkPositiveInteger(instruction);
-  }
-
-  TypeMask visitNegate(HNegate instruction) {
-    HInstruction operand = instruction.operand;
-    // We have integer subclasses that represent ranges, so widen any int
-    // subclass to full integer.
-    if (operand.isInteger(compiler)) return backend.intType;
-    return instruction.operand.instructionType;
-  }
-
-  TypeMask visitInstruction(HInstruction instruction) {
-    assert(instruction.instructionType != null);
-    return instruction.instructionType;
-  }
-
-  TypeMask visitPhi(HPhi phi) {
-    TypeMask candidateType = backend.emptyType;
-    for (int i = 0, length = phi.inputs.length; i < length; i++) {
-      TypeMask inputType = phi.inputs[i].instructionType;
-      candidateType = candidateType.union(inputType, classWorld);
-    }
-    return candidateType;
-  }
-
-  TypeMask visitTypeConversion(HTypeConversion instruction) {
-    HInstruction input = instruction.checkedInput;
-    TypeMask inputType = input.instructionType;
-    TypeMask checkedType = instruction.checkedType;
-    if (instruction.isArgumentTypeCheck || instruction.isReceiverTypeCheck) {
-      // We must make sure a type conversion for receiver or argument check
-      // does not try to do an int check, because an int check is not enough.
-      // We only do an int check if the input is integer or null.
-      if (checkedType.containsOnlyNum(classWorld)
-          && !checkedType.containsOnlyDouble(classWorld)
-          && input.isIntegerOrNull(compiler)) {
-        instruction.checkedType = backend.intType;
-      } else if (checkedType.containsOnlyInt(classWorld)
-                 && !input.isIntegerOrNull(compiler)) {
-        instruction.checkedType = backend.numType;
-      }
-    }
-
-    TypeMask outputType = checkedType.intersection(inputType, classWorld);
-    if (outputType.isEmpty && !outputType.isNullable) {
-      // Intersection of double and integer conflicts (is empty), but JS numbers
-      // can be both int and double at the same time.  For example, the input
-      // can be a literal double '8.0' that is marked as an integer (because 'is
-      // int' will return 'true').  What we really need to do is make the
-      // overlap between int and double values explicit in the TypeMask system.
-      if (inputType.containsOnlyInt(classWorld)
-          && checkedType.containsOnlyDouble(classWorld)) {
-        if (inputType.isNullable && checkedType.isNullable) {
-          outputType = backend.doubleType.nullable();
-        } else {
-          outputType = backend.doubleType;
-        }
-      }
-    }
-    return outputType;
-  }
-
-  TypeMask visitTypeKnown(HTypeKnown instruction) {
-    HInstruction input = instruction.checkedInput;
-    return instruction.knownType.intersection(
-        input.instructionType, classWorld);
-  }
-
-  void convertInput(HInvokeDynamic instruction,
-                    HInstruction input,
-                    TypeMask type,
-                    int kind) {
-    Selector selector = (kind == HTypeConversion.RECEIVER_TYPE_CHECK)
-        ? instruction.selector
-        : null;
-    HTypeConversion converted = new HTypeConversion(
-        null, kind, type, input, selector);
-    instruction.block.addBefore(instruction, converted);
-    input.replaceAllUsersDominatedBy(instruction, converted);
-  }
-
-  bool isCheckEnoughForNsmOrAe(HInstruction instruction,
-                               TypeMask type) {
-    // In some cases, we want the receiver to be an integer,
-    // but that does not mean we will get a NoSuchMethodError
-    // if it's not: the receiver could be a double.
-    if (type.containsOnlyInt(classWorld)) {
-      // If the instruction's type is integer or null, the codegen
-      // will emit a null check, which is enough to know if it will
-      // hit a noSuchMethod.
-      return instruction.isIntegerOrNull(compiler);
-    }
-    return true;
-  }
-
-  // Add a receiver type check when the call can only hit
-  // [noSuchMethod] if the receiver is not of a specific type.
-  // Return true if the receiver type check was added.
-  bool checkReceiver(HInvokeDynamic instruction) {
-    assert(instruction.isInterceptedCall);
-    HInstruction receiver = instruction.inputs[1];
-    if (receiver.isNumber(compiler)) return false;
-    if (receiver.isNumberOrNull(compiler)) {
-      convertInput(instruction,
-                   receiver,
-                   receiver.instructionType.nonNullable(),
-                   HTypeConversion.RECEIVER_TYPE_CHECK);
-      return true;
-    } else if (instruction.element == null) {
-      Iterable<Element> targets =
-          compiler.world.allFunctions.filter(instruction.selector);
-      if (targets.length == 1) {
-        Element target = targets.first;
-        ClassElement cls = target.enclosingClass;
-        TypeMask type = new TypeMask.nonNullSubclass(
-            cls.declaration, classWorld);
-        // TODO(ngeoffray): We currently only optimize on primitive
-        // types.
-        if (!type.satisfies(backend.jsIndexableClass, classWorld) &&
-            !type.containsOnlyNum(classWorld) &&
-            !type.containsOnlyBool(classWorld)) {
-          return false;
-        }
-        if (!isCheckEnoughForNsmOrAe(receiver, type)) return false;
-        instruction.element = target;
-        convertInput(instruction,
-                     receiver,
-                     type,
-                     HTypeConversion.RECEIVER_TYPE_CHECK);
-        return true;
-      }
-    }
-    return false;
-  }
-
-  // Add an argument type check if the argument is not of a type
-  // expected by the call.
-  // Return true if the argument type check was added.
-  bool checkArgument(HInvokeDynamic instruction) {
-    // We want the right error in checked mode.
-    if (compiler.enableTypeAssertions) return false;
-    HInstruction left = instruction.inputs[1];
-    HInstruction right = instruction.inputs[2];
-
-    Selector selector = instruction.selector;
-    if (selector.isOperator && left.isNumber(compiler)) {
-      if (right.isNumber(compiler)) return false;
-      TypeMask type = right.isIntegerOrNull(compiler)
-          ? right.instructionType.nonNullable()
-          : backend.numType;
-      // TODO(ngeoffray): Some number operations don't have a builtin
-      // variant and will do the check in their method anyway. We
-      // still add a check because it allows to GVN these operations,
-      // but we should find a better way.
-      convertInput(instruction,
-                   right,
-                   type,
-                   HTypeConversion.ARGUMENT_TYPE_CHECK);
-      return true;
-    }
-    return false;
-  }
-
-  void processPendingOptimizations() {
-    pendingOptimizations.forEach((instruction, action) => action());
-    pendingOptimizations.clear();
-  }
-
-  void addDependentInstructionsToWorkList(HInstruction instruction) {
-    for (int i = 0, length = instruction.usedBy.length; i < length; i++) {
-      // The type propagator only propagates types forward. We
-      // thus only need to add the users of the [instruction] to the list.
-      addToWorkList(instruction.usedBy[i]);
-    }
-  }
-
-  void addAllUsersBut(HInvokeDynamic invoke, HInstruction instruction) {
-    instruction.usedBy.forEach((HInstruction user) {
-      if (user != invoke) addToWorkList(user);
-    });
-  }
-
-  TypeMask visitInvokeDynamic(HInvokeDynamic instruction) {
-    if (instruction.isInterceptedCall) {
-      // We cannot do the following optimization now, because we have
-      // to wait for the type propagation to be stable. The receiver
-      // of [instruction] might move from number to dynamic.
-      pendingOptimizations.putIfAbsent(instruction, () => () {
-        Selector selector = instruction.selector;
-        if (selector.isOperator && selector.name != '==') {
-          if (checkReceiver(instruction)) {
-            addAllUsersBut(instruction, instruction.inputs[1]);
-          }
-          if (!selector.isUnaryOperator && checkArgument(instruction)) {
-            addAllUsersBut(instruction, instruction.inputs[2]);
-          }
-        }
-      });
-    }
-
-    HInstruction receiver = instruction.getDartReceiver(compiler);
-    TypeMask receiverType = receiver.instructionType;
-    Selector selector =
-        new TypedSelector(receiverType, instruction.selector, classWorld);
-    instruction.selector = selector;
-
-    // Try to specialize the receiver after this call.
-    if (receiver.dominatedUsers(instruction).length != 1
-        && !selector.isClosureCall) {
-      TypeMask newType = compiler.world.allFunctions.receiverType(selector);
-      newType = newType.intersection(receiverType, classWorld);
-      var next = instruction.next;
-      if (next is HTypeKnown && next.checkedInput == receiver) {
-        // We already have refined [receiver]. We still update the
-        // type of the [HTypeKnown] instruction because it may have
-        // been refined with a correct type at the time, but
-        // incorrect now.
-        if (next.instructionType != newType) {
-          next.knownType = next.instructionType = newType;
-          addDependentInstructionsToWorkList(next);
-        }
-      } else if (newType != receiverType) {
-        // Insert a refinement node after the call and update all
-        // users dominated by the call to use that node instead of
-        // [receiver].
-        HTypeKnown converted =
-            new HTypeKnown.witnessed(newType, receiver, instruction);
-        instruction.block.addBefore(instruction.next, converted);
-        receiver.replaceAllUsersDominatedBy(converted.next, converted);
-        addDependentInstructionsToWorkList(converted);
-      }
-    }
-
-    return instruction.specializer.computeTypeFromInputTypes(
-        instruction, compiler);
-  }
-}