double * int returns a double can be simplified to an int if both operands are constants. Therefore…

sdk/lib/_internal/compiler/implementation/ssa/nodes.dart

 // 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;
 
 abstract class HVisitor<R> {
   R visitAdd(HAdd node);
   R visitBitAnd(HBitAnd node);
   R visitBitNot(HBitNot node);
@@ skipping 1913 matching lines @@
   bool isConstantList() => constant.isList();
   bool isConstantMap() => constant.isMap();
   bool isConstantFalse() => constant.isFalse();
   bool isConstantTrue() => constant.isTrue();
   bool isConstantSentinel() => constant.isSentinel();
 
   bool isInterceptor(Compiler compiler) => constant.isInterceptor();
 
   // Maybe avoid this if the literal is big?
   bool isCodeMotionInvariant() => true;
+
+  set instructionType(type) {
+    assert((type.isEmpty && super.instructionType.isEmpty)
+           || !type.isNullable);
+    super.instructionType = type;
+  }
 }
 
 class HNot extends HInstruction {
   HNot(HInstruction value, TypeMask type) : super(<HInstruction>[value], type) {
     setUseGvn();
   }
 
   accept(HVisitor visitor) => visitor.visitNot(this);
   int typeCode() => HInstruction.NOT_TYPECODE;
   bool typeEquals(other) => other is HNot;
@@ skipping 955 matching lines @@
 class HDynamicType extends HRuntimeType {
   HDynamicType(DynamicType dartType, TypeMask instructionType)
       : super(const <HInstruction>[], dartType, instructionType);
 
   accept(HVisitor visitor) => visitor.visitDynamicType(this);
 
   int typeCode() => HInstruction.DYNAMIC_TYPE_TYPECODE;
 
   bool typeEquals(HInstruction other) => other is HDynamicType;
 }