89                 return true;
  90         }
  91     }
  92 
  93     @Override
  94     public ValueNode canonical(CanonicalizerTool tool, ValueNode forValue) {
  95         ValueNode ret = super.canonical(tool, forValue);
  96         if (ret != this) {
  97             return ret;
  98         }
  99 
 100         if (forValue instanceof ZeroExtendNode) {
 101             // xxxx -(zero-extend)-> 0000 xxxx -(zero-extend)-> 00000000 0000xxxx
 102             // ==> xxxx -(zero-extend)-> 00000000 0000xxxx
 103             ZeroExtendNode other = (ZeroExtendNode) forValue;
 104             return new ZeroExtendNode(other.getValue(), other.getInputBits(), getResultBits());
 105         }
 106         if (forValue instanceof NarrowNode) {
 107             NarrowNode narrow = (NarrowNode) forValue;
 108             Stamp inputStamp = narrow.getValue().stamp();
 109             if (inputStamp instanceof IntegerStamp && inputStamp.isCompatible(stamp())) {
 110                 IntegerStamp istamp = (IntegerStamp) inputStamp;
 111                 long mask = CodeUtil.mask(PrimitiveStamp.getBits(narrow.stamp()));
 112                 if (((istamp.upMask() | istamp.downMask()) & ~mask) == 0) {
 113                     // The original value is in the range of the masked zero extended result so
 114                     // simply return the original input.










 115                     return narrow.getValue();
 116                 }
 117             }
 118         }

 119 
 120         return this;
 121     }
 122 
 123     @Override
 124     public void generate(NodeLIRBuilderTool nodeValueMap, ArithmeticLIRGeneratorTool gen) {
 125         nodeValueMap.setResult(this, gen.emitZeroExtend(nodeValueMap.operand(getValue()), getInputBits(), getResultBits()));
 126     }





 127 }

  89                 return true;
  90         }
  91     }
  92 
  93     @Override
  94     public ValueNode canonical(CanonicalizerTool tool, ValueNode forValue) {
  95         ValueNode ret = super.canonical(tool, forValue);
  96         if (ret != this) {
  97             return ret;
  98         }
  99 
 100         if (forValue instanceof ZeroExtendNode) {
 101             // xxxx -(zero-extend)-> 0000 xxxx -(zero-extend)-> 00000000 0000xxxx
 102             // ==> xxxx -(zero-extend)-> 00000000 0000xxxx
 103             ZeroExtendNode other = (ZeroExtendNode) forValue;
 104             return new ZeroExtendNode(other.getValue(), other.getInputBits(), getResultBits());
 105         }
 106         if (forValue instanceof NarrowNode) {
 107             NarrowNode narrow = (NarrowNode) forValue;
 108             Stamp inputStamp = narrow.getValue().stamp();
 109             if (inputStamp instanceof IntegerStamp) {
 110                 IntegerStamp istamp = (IntegerStamp) inputStamp;
 111                 long mask = CodeUtil.mask(PrimitiveStamp.getBits(narrow.stamp()));
 112 
 113                 if ((istamp.upMask() & ~mask) == 0) {
 114                     // The original value cannot change because of the narrow and zero extend.
 115 
 116                     if (istamp.getBits() < resultBits) {
 117                         // Need to keep the zero extend, skip the narrow.
 118                         return create(narrow.getValue(), resultBits);
 119                     } else if (istamp.getBits() > resultBits) {
 120                         // Need to keep the narrow, skip the zero extend.
 121                         return NarrowNode.create(narrow.getValue(), resultBits);
 122                     } else {
 123                         assert istamp.getBits() == resultBits;
 124                         // Just return the original value.
 125                         return narrow.getValue();
 126                     }
 127                 }
 128             }
 129         }
 130 
 131         return this;
 132     }
 133 
 134     @Override
 135     public void generate(NodeLIRBuilderTool nodeValueMap, ArithmeticLIRGeneratorTool gen) {
 136         nodeValueMap.setResult(this, gen.emitZeroExtend(nodeValueMap.operand(getValue()), getInputBits(), getResultBits()));
 137     }
 138 
 139     @Override
 140     public boolean mayNullCheckSkipConversion() {
 141         return true;
 142     }
 143 }