Optimize DateTime properties

pkg/compiler/lib/src/ssa/types_propagation.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;
 
 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 =
@@ skipping 114 matching lines @@
 
   TypeMask visitAdd(HAdd instruction) {
     return checkPositiveInteger(instruction);
   }
 
   TypeMask visitDivide(HDivide instruction) {
     // Always double, as initialized.
     return instruction.instructionType;
   }
 
+  TypeMask visitTruncatingDivide(HTruncatingDivide instruction) {
+    // Always as initialized.
+    return instruction.instructionType;
+  }
+
   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);
@@ skipping 222 matching lines @@
         instruction.block.addBefore(instruction.next, converted);
         receiver.replaceAllUsersDominatedBy(converted.next, converted);
         addDependentInstructionsToWorkList(converted);
       }
     }
 
     return instruction.specializer.computeTypeFromInputTypes(
         instruction, compiler);
   }
 }