baksmali/src/main/java/org/jf/baksmali/Adaptors/Format/InstructionMethodItem.java - platform/external/smali - Git at Google

 /*
  * [The "BSD licence"]
  * Copyright (c) 2010 Ben Gruver (JesusFreke)
  * All rights reserved.
  *
  * Redistribution and use in source and binary forms, with or without
  * modification, are permitted provided that the following conditions
  * are met:
  * 1. Redistributions of source code must retain the above copyright
  *    notice, this list of conditions and the following disclaimer.
  * 2. Redistributions in binary form must reproduce the above copyright
  *    notice, this list of conditions and the following disclaimer in the
  *    documentation and/or other materials provided with the distribution.
  * 3. The name of the author may not be used to endorse or promote products
  *    derived from this software without specific prior written permission.
  *
  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
  * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
  * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
  * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
  * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
  * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  * INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
  * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  */

 package org.jf.baksmali.Adaptors.Format;

 import org.jf.baksmali.Adaptors.MethodDefinition;
 import org.jf.baksmali.Adaptors.MethodDefinition.InvalidSwitchPayload;
 import org.jf.baksmali.Adaptors.MethodItem;
 import org.jf.baksmali.Renderers.LongRenderer;
 import org.jf.baksmali.BaksmaliOptions;
 import org.jf.dexlib2.Opcode;
 import org.jf.dexlib2.ReferenceType;
 import org.jf.dexlib2.VerificationError;
 import org.jf.dexlib2.dexbacked.DexBackedDexFile.InvalidItemIndex;
 import org.jf.dexlib2.iface.instruction.*;
 import org.jf.dexlib2.iface.instruction.formats.Instruction20bc;
 import org.jf.dexlib2.iface.instruction.formats.Instruction31t;
 import org.jf.dexlib2.iface.instruction.formats.UnknownInstruction;
 import org.jf.dexlib2.iface.reference.Reference;
 import org.jf.dexlib2.util.ReferenceUtil;
 import org.jf.util.ExceptionWithContext;
 import org.jf.util.IndentingWriter;
 import org.jf.util.NumberUtils;

 import javax.annotation.Nonnull;
 import java.io.IOException;
 import java.util.Map;

 public class InstructionMethodItem<T extends Instruction> extends MethodItem {
     @Nonnull protected final MethodDefinition methodDef;
     @Nonnull protected final T instruction;

     public InstructionMethodItem(@Nonnull MethodDefinition methodDef, int codeAddress, @Nonnull T instruction) {
         super(codeAddress);
         this.methodDef = methodDef;
         this.instruction = instruction;
     }

     public double getSortOrder() {
         //instructions should appear after everything except an "end try" label and .catch directive
         return 100;
     }

     private boolean isAllowedOdex(@Nonnull Opcode opcode) {
         BaksmaliOptions options = methodDef.classDef.options;
         if (options.allowOdex) {
             return true;
         }

         if (methodDef.classDef.options.apiLevel >= 14) {
             return false;
         }

         return opcode.isVolatileFieldAccessor() || opcode == Opcode.THROW_VERIFICATION_ERROR;
     }

     private String writeInvalidItemIndex(InvalidItemIndex ex, int type, IndentingWriter writer)
             throws IOException {
         writer.write("#");
         writer.write(ex.getMessage());
         writer.write("\n");
         return String.format("%s@%d", ReferenceType.toString(type), ex.getInvalidIndex());
     }

     @Override
     public boolean writeTo(IndentingWriter writer) throws IOException {
         Opcode opcode = instruction.getOpcode();
         String verificationErrorName = null;
         String referenceString = null;
         String referenceString2 = null;

         boolean commentOutInstruction = false;

         if (instruction instanceof Instruction20bc) {
             int verificationError = ((Instruction20bc)instruction).getVerificationError();
             verificationErrorName = VerificationError.getVerificationErrorName(verificationError);
             if (verificationErrorName == null) {
                 writer.write("#was invalid verification error type: ");
                 writer.printSignedIntAsDec(verificationError);
                 writer.write("\n");
                 verificationErrorName = "generic-error";
             }
         }

         if (instruction instanceof ReferenceInstruction) {
             ReferenceInstruction referenceInstruction = (ReferenceInstruction)instruction;
             String classContext = null;
             if (methodDef.classDef.options.implicitReferences) {
                 classContext = methodDef.method.getDefiningClass();
             }

             try {
                 Reference reference = referenceInstruction.getReference();
                 referenceString = ReferenceUtil.getReferenceString(reference, classContext);
                 assert referenceString != null;
             } catch (InvalidItemIndex ex) {
                 commentOutInstruction = true;
                 referenceString = writeInvalidItemIndex(ex, referenceInstruction.getReferenceType(),
                         writer);
             } catch (ReferenceType.InvalidReferenceTypeException ex) {
                 writer.write("#invalid reference type: ");
                 writer.printSignedIntAsDec(ex.getReferenceType());
                 commentOutInstruction = true;

                 referenceString = "invalid_reference";
             }

             if (instruction instanceof DualReferenceInstruction) {
                 DualReferenceInstruction dualReferenceInstruction =
                         (DualReferenceInstruction) instruction;
                 try {
                     Reference reference2 = dualReferenceInstruction.getReference2();
                     referenceString2 = ReferenceUtil.getReferenceString(reference2, classContext);
                 } catch (InvalidItemIndex ex) {
                     commentOutInstruction = true;
                     referenceString2 = writeInvalidItemIndex(ex,
                             dualReferenceInstruction.getReferenceType2(), writer);
                 } catch (ReferenceType.InvalidReferenceTypeException ex) {
                     writer.write("#invalid reference type: ");
                     writer.printSignedIntAsDec(ex.getReferenceType());
                     commentOutInstruction = true;

                     referenceString2 = "invalid_reference";
                 }
             }
         }

         if (instruction instanceof Instruction31t) {
             boolean validPayload = true;

             switch (instruction.getOpcode()) {
                 case PACKED_SWITCH:
                     int baseAddress = methodDef.getPackedSwitchBaseAddress(
                             this.codeAddress + ((Instruction31t)instruction).getCodeOffset());
                     if (baseAddress == -1) {
                         validPayload = false;
                     }
                     break;
                 case SPARSE_SWITCH:
                     baseAddress = methodDef.getSparseSwitchBaseAddress(
                             this.codeAddress + ((Instruction31t)instruction).getCodeOffset());
                     if (baseAddress == -1) {
                         validPayload = false;
                     }
                     break;
                 case FILL_ARRAY_DATA:
                     try {
                         methodDef.findPayloadOffset(this.codeAddress + ((Instruction31t)instruction).getCodeOffset(),
                                 Opcode.ARRAY_PAYLOAD);
                     } catch (InvalidSwitchPayload ex) {
                         validPayload = false;
                     }
                     break;
                 default:
                     throw new ExceptionWithContext("Invalid 31t opcode: %s", instruction.getOpcode());
             }

             if (!validPayload) {
                 writer.write("#invalid payload reference\n");
                 commentOutInstruction = true;
             }
         }

         if (opcode.odexOnly()) {
             if (!isAllowedOdex(opcode)) {
                 writer.write("#disallowed odex opcode\n");
                 commentOutInstruction = true;
             }
         }

         if (commentOutInstruction) {
             writer.write("#");
         }

         switch (instruction.getOpcode().format) {
             case Format10t:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeTargetLabel(writer);
                 break;
             case Format10x:
                 if (instruction instanceof UnknownInstruction) {
                     writer.write("#unknown opcode: 0x");
                     writer.printUnsignedLongAsHex(((UnknownInstruction)instruction).getOriginalOpcode());
                     writer.write('\n');
                 }
                 writeOpcode(writer);
                 break;
             case Format11n:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 writer.write(", ");
                 writeLiteral(writer);
                 break;
             case Format11x:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 break;
             case Format12x:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 writer.write(", ");
                 writeSecondRegister(writer);
                 break;
             case Format20bc:
                 writeOpcode(writer);
                 writer.write(' ');
                 writer.write(verificationErrorName);
                 writer.write(", ");
                 writer.write(referenceString);
                 break;
             case Format20t:
             case Format30t:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeTargetLabel(writer);
                 break;
             case Format21c:
             case Format31c:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 writer.write(", ");
                 writer.write(referenceString);
                 break;
             case Format21ih:
             case Format21lh:
             case Format21s:
             case Format31i:
             case Format51l:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 writer.write(", ");
                 writeLiteral(writer);
                 if (instruction.getOpcode().setsWideRegister()) {
                     writeCommentIfLikelyDouble(writer);
                 } else {
                     boolean isResourceId = writeCommentIfResourceId(writer);
                     if (!isResourceId) writeCommentIfLikelyFloat(writer);
                 }
                 break;
             case Format21t:
             case Format31t:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 writer.write(", ");
                 writeTargetLabel(writer);
                 break;
             case Format22b:
             case Format22s:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 writer.write(", ");
                 writeSecondRegister(writer);
                 writer.write(", ");
                 writeLiteral(writer);
                 break;
             case Format22c:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 writer.write(", ");
                 writeSecondRegister(writer);
                 writer.write(", ");
                 writer.write(referenceString);
                 break;
             case Format22cs:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 writer.write(", ");
                 writeSecondRegister(writer);
                 writer.write(", ");
                 writeFieldOffset(writer);
                 break;
             case Format22t:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 writer.write(", ");
                 writeSecondRegister(writer);
                 writer.write(", ");
                 writeTargetLabel(writer);
                 break;
             case Format22x:
             case Format32x:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 writer.write(", ");
                 writeSecondRegister(writer);
                 break;
             case Format23x:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeFirstRegister(writer);
                 writer.write(", ");
                 writeSecondRegister(writer);
                 writer.write(", ");
                 writeThirdRegister(writer);
                 break;
             case Format35c:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeInvokeRegisters(writer);
                 writer.write(", ");
                 writer.write(referenceString);
                 break;
             case Format35mi:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeInvokeRegisters(writer);
                 writer.write(", ");
                 writeInlineIndex(writer);
                 break;
             case Format35ms:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeInvokeRegisters(writer);
                 writer.write(", ");
                 writeVtableIndex(writer);
                 break;
             case Format3rc:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeInvokeRangeRegisters(writer);
                 writer.write(", ");
                 writer.write(referenceString);
                 break;
             case Format3rmi:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeInvokeRangeRegisters(writer);
                 writer.write(", ");
                 writeInlineIndex(writer);
                 break;
             case Format3rms:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeInvokeRangeRegisters(writer);
                 writer.write(", ");
                 writeVtableIndex(writer);
                 break;
             case Format45cc:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeInvokeRegisters(writer);
                 writer.write(", ");
                 writer.write(referenceString);
                 writer.write(", ");
                 writer.write(referenceString2);
                 break;
             case Format4rcc:
                 writeOpcode(writer);
                 writer.write(' ');
                 writeInvokeRangeRegisters(writer);
                 writer.write(", ");
                 writer.write(referenceString);
                 writer.write(", ");
                 writer.write(referenceString2);
                 break;
             default:
                 assert false;
                 return false;
         }

         if (commentOutInstruction) {
             writer.write("\nnop");
         }

         return true;
     }

     protected void writeOpcode(IndentingWriter writer) throws IOException {
         writer.write(instruction.getOpcode().name);
     }

     protected void writeTargetLabel(IndentingWriter writer) throws IOException {
         //this method is overridden by OffsetInstructionMethodItem, and should only be called for the formats that
         //have a target
         throw new RuntimeException();
     }

     protected void writeRegister(IndentingWriter writer, int registerNumber) throws IOException {
         methodDef.registerFormatter.writeTo(writer, registerNumber);
     }

     protected void writeFirstRegister(IndentingWriter writer) throws IOException {
         writeRegister(writer, ((OneRegisterInstruction)instruction).getRegisterA());
     }

     protected void writeSecondRegister(IndentingWriter writer) throws IOException {
         writeRegister(writer, ((TwoRegisterInstruction)instruction).getRegisterB());
     }

     protected void writeThirdRegister(IndentingWriter writer) throws IOException {
         writeRegister(writer, ((ThreeRegisterInstruction) instruction).getRegisterC());
     }

     protected void writeInvokeRegisters(IndentingWriter writer) throws IOException {
         FiveRegisterInstruction instruction = (FiveRegisterInstruction)this.instruction;
         final int regCount = instruction.getRegisterCount();

         writer.write('{');
         switch (regCount) {
             case 1:
                 writeRegister(writer, instruction.getRegisterC());
                 break;
             case 2:
                 writeRegister(writer, instruction.getRegisterC());
                 writer.write(", ");
                 writeRegister(writer, instruction.getRegisterD());
                 break;
             case 3:
                 writeRegister(writer, instruction.getRegisterC());
                 writer.write(", ");
                 writeRegister(writer, instruction.getRegisterD());
                 writer.write(", ");
                 writeRegister(writer, instruction.getRegisterE());
                 break;
             case 4:
                 writeRegister(writer, instruction.getRegisterC());
                 writer.write(", ");
                 writeRegister(writer, instruction.getRegisterD());
                 writer.write(", ");
                 writeRegister(writer, instruction.getRegisterE());
                 writer.write(", ");
                 writeRegister(writer, instruction.getRegisterF());
                 break;
             case 5:
                 writeRegister(writer, instruction.getRegisterC());
                 writer.write(", ");
                 writeRegister(writer, instruction.getRegisterD());
                 writer.write(", ");
                 writeRegister(writer, instruction.getRegisterE());
                 writer.write(", ");
                 writeRegister(writer, instruction.getRegisterF());
                 writer.write(", ");
                 writeRegister(writer, instruction.getRegisterG());
                 break;
         }
         writer.write('}');
     }

     protected void writeInvokeRangeRegisters(IndentingWriter writer) throws IOException {
         RegisterRangeInstruction instruction = (RegisterRangeInstruction)this.instruction;

         int regCount = instruction.getRegisterCount();
         if (regCount == 0) {
             writer.write("{}");
         } else {
             int startRegister = instruction.getStartRegister();
             methodDef.registerFormatter.writeRegisterRange(writer, startRegister, startRegister+regCount-1);
         }
     }

     protected void writeLiteral(IndentingWriter writer) throws IOException {
         LongRenderer.writeSignedIntOrLongTo(writer, ((WideLiteralInstruction)instruction).getWideLiteral());
     }

     protected void writeCommentIfLikelyFloat(IndentingWriter writer) throws IOException {
         writeCommentIfLikelyFloat(writer, ((NarrowLiteralInstruction)instruction).getNarrowLiteral());
     }

     protected void writeCommentIfLikelyFloat(IndentingWriter writer, int val) throws IOException {
         if (NumberUtils.isLikelyFloat(val)) {
             writer.write("    # ");
             float fval = Float.intBitsToFloat(val);
             if (fval == Float.POSITIVE_INFINITY)
                 writer.write("Float.POSITIVE_INFINITY");
             else if (fval == Float.NEGATIVE_INFINITY)
                 writer.write("Float.NEGATIVE_INFINITY");
             else if (Float.isNaN(fval))
                 writer.write("Float.NaN");
             else if (fval == Float.MAX_VALUE)
                 writer.write("Float.MAX_VALUE");
             else if (fval == (float)Math.PI)
                 writer.write("(float)Math.PI");
             else if (fval == (float)Math.E)
                 writer.write("(float)Math.E");
             else {
                 writer.write(Float.toString(fval));
                 writer.write('f');
             }
         }
     }

     protected void writeCommentIfLikelyDouble(IndentingWriter writer) throws IOException {
         writeCommentIfLikelyDouble(writer, ((WideLiteralInstruction)instruction).getWideLiteral());
     }

     protected void writeCommentIfLikelyDouble(IndentingWriter writer, long val) throws IOException {
         if (NumberUtils.isLikelyDouble(val)) {
             writer.write("    # ");
             double dval = Double.longBitsToDouble(val);
             if (dval == Double.POSITIVE_INFINITY)
                 writer.write("Double.POSITIVE_INFINITY");
             else if (dval == Double.NEGATIVE_INFINITY)
                 writer.write("Double.NEGATIVE_INFINITY");
             else if (Double.isNaN(dval))
                 writer.write("Double.NaN");
             else if (dval == Double.MAX_VALUE)
                 writer.write("Double.MAX_VALUE");
             else if (dval == Math.PI)
                 writer.write("Math.PI");
             else if (dval == Math.E)
                 writer.write("Math.E");
             else
                 writer.write(Double.toString(dval));
         }
     }

     protected boolean writeCommentIfResourceId(IndentingWriter writer) throws IOException {
         return writeCommentIfResourceId(writer, ((NarrowLiteralInstruction)instruction).getNarrowLiteral());
     }

     protected boolean writeCommentIfResourceId(IndentingWriter writer, int val) throws IOException {
         Map<Integer,String> resourceIds = methodDef.classDef.options.resourceIds;
         String resource = resourceIds.get(Integer.valueOf(val));
         if (resource != null) {
             writer.write("    # ");
             writer.write(resource);
             return true;
         }
         return false;
     }

     protected void writeFieldOffset(IndentingWriter writer) throws IOException {
         writer.write("field@0x");
         writer.printUnsignedLongAsHex(((FieldOffsetInstruction)instruction).getFieldOffset());
     }

     protected void writeInlineIndex(IndentingWriter writer) throws IOException {
         writer.write("inline@");
         writer.printSignedIntAsDec(((InlineIndexInstruction)instruction).getInlineIndex());
     }

     protected void writeVtableIndex(IndentingWriter writer) throws IOException {
         writer.write("vtable@");
         writer.printSignedIntAsDec(((VtableIndexInstruction)instruction).getVtableIndex());
     }
 }
	/*
	* [The "BSD licence"]
	* Copyright (c) 2010 Ben Gruver (JesusFreke)
	* All rights reserved.
	*
	* Redistribution and use in source and binary forms, with or without
	* modification, are permitted provided that the following conditions
	* are met:
	* 1. Redistributions of source code must retain the above copyright
	* notice, this list of conditions and the following disclaimer.
	* 2. Redistributions in binary form must reproduce the above copyright
	* notice, this list of conditions and the following disclaimer in the
	* documentation and/or other materials provided with the distribution.
	* 3. The name of the author may not be used to endorse or promote products
	* derived from this software without specific prior written permission.
	*
	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
	* INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
	*/

	package org.jf.baksmali.Adaptors.Format;

	import org.jf.baksmali.Adaptors.MethodDefinition;
	import org.jf.baksmali.Adaptors.MethodDefinition.InvalidSwitchPayload;
	import org.jf.baksmali.Adaptors.MethodItem;
	import org.jf.baksmali.Renderers.LongRenderer;
	import org.jf.baksmali.BaksmaliOptions;
	import org.jf.dexlib2.Opcode;
	import org.jf.dexlib2.ReferenceType;
	import org.jf.dexlib2.VerificationError;
	import org.jf.dexlib2.dexbacked.DexBackedDexFile.InvalidItemIndex;
	import org.jf.dexlib2.iface.instruction.*;
	import org.jf.dexlib2.iface.instruction.formats.Instruction20bc;
	import org.jf.dexlib2.iface.instruction.formats.Instruction31t;
	import org.jf.dexlib2.iface.instruction.formats.UnknownInstruction;
	import org.jf.dexlib2.iface.reference.Reference;
	import org.jf.dexlib2.util.ReferenceUtil;
	import org.jf.util.ExceptionWithContext;
	import org.jf.util.IndentingWriter;
	import org.jf.util.NumberUtils;

	import javax.annotation.Nonnull;
	import java.io.IOException;
	import java.util.Map;

	public class InstructionMethodItem<T extends Instruction> extends MethodItem {
	@Nonnull protected final MethodDefinition methodDef;
	@Nonnull protected final T instruction;

	public InstructionMethodItem(@Nonnull MethodDefinition methodDef, int codeAddress, @Nonnull T instruction) {
	super(codeAddress);
	this.methodDef = methodDef;
	this.instruction = instruction;
	}

	public double getSortOrder() {
	//instructions should appear after everything except an "end try" label and .catch directive
	return 100;
	}

	private boolean isAllowedOdex(@Nonnull Opcode opcode) {
	BaksmaliOptions options = methodDef.classDef.options;
	if (options.allowOdex) {
	return true;
	}

	if (methodDef.classDef.options.apiLevel >= 14) {
	return false;
	}

	return opcode.isVolatileFieldAccessor() \|\| opcode == Opcode.THROW_VERIFICATION_ERROR;
	}

	private String writeInvalidItemIndex(InvalidItemIndex ex, int type, IndentingWriter writer)
	throws IOException {
	writer.write("#");
	writer.write(ex.getMessage());
	writer.write("\n");
	return String.format("%s@%d", ReferenceType.toString(type), ex.getInvalidIndex());
	}

	@Override
	public boolean writeTo(IndentingWriter writer) throws IOException {
	Opcode opcode = instruction.getOpcode();
	String verificationErrorName = null;
	String referenceString = null;
	String referenceString2 = null;

	boolean commentOutInstruction = false;

	if (instruction instanceof Instruction20bc) {
	int verificationError = ((Instruction20bc)instruction).getVerificationError();
	verificationErrorName = VerificationError.getVerificationErrorName(verificationError);
	if (verificationErrorName == null) {
	writer.write("#was invalid verification error type: ");
	writer.printSignedIntAsDec(verificationError);
	writer.write("\n");
	verificationErrorName = "generic-error";
	}
	}

	if (instruction instanceof ReferenceInstruction) {
	ReferenceInstruction referenceInstruction = (ReferenceInstruction)instruction;
	String classContext = null;
	if (methodDef.classDef.options.implicitReferences) {
	classContext = methodDef.method.getDefiningClass();
	}

	try {
	Reference reference = referenceInstruction.getReference();
	referenceString = ReferenceUtil.getReferenceString(reference, classContext);
	assert referenceString != null;
	} catch (InvalidItemIndex ex) {
	commentOutInstruction = true;
	referenceString = writeInvalidItemIndex(ex, referenceInstruction.getReferenceType(),
	writer);
	} catch (ReferenceType.InvalidReferenceTypeException ex) {
	writer.write("#invalid reference type: ");
	writer.printSignedIntAsDec(ex.getReferenceType());
	commentOutInstruction = true;

	referenceString = "invalid_reference";
	}

	if (instruction instanceof DualReferenceInstruction) {
	DualReferenceInstruction dualReferenceInstruction =
	(DualReferenceInstruction) instruction;
	try {
	Reference reference2 = dualReferenceInstruction.getReference2();
	referenceString2 = ReferenceUtil.getReferenceString(reference2, classContext);
	} catch (InvalidItemIndex ex) {
	commentOutInstruction = true;
	referenceString2 = writeInvalidItemIndex(ex,
	dualReferenceInstruction.getReferenceType2(), writer);
	} catch (ReferenceType.InvalidReferenceTypeException ex) {
	writer.write("#invalid reference type: ");
	writer.printSignedIntAsDec(ex.getReferenceType());
	commentOutInstruction = true;

	referenceString2 = "invalid_reference";
	}
	}
	}

	if (instruction instanceof Instruction31t) {
	boolean validPayload = true;

	switch (instruction.getOpcode()) {
	case PACKED_SWITCH:
	int baseAddress = methodDef.getPackedSwitchBaseAddress(
	this.codeAddress + ((Instruction31t)instruction).getCodeOffset());
	if (baseAddress == -1) {
	validPayload = false;
	}
	break;
	case SPARSE_SWITCH:
	baseAddress = methodDef.getSparseSwitchBaseAddress(
	this.codeAddress + ((Instruction31t)instruction).getCodeOffset());
	if (baseAddress == -1) {
	validPayload = false;
	}
	break;
	case FILL_ARRAY_DATA:
	try {
	methodDef.findPayloadOffset(this.codeAddress + ((Instruction31t)instruction).getCodeOffset(),
	Opcode.ARRAY_PAYLOAD);
	} catch (InvalidSwitchPayload ex) {
	validPayload = false;
	}
	break;
	default:
	throw new ExceptionWithContext("Invalid 31t opcode: %s", instruction.getOpcode());
	}

	if (!validPayload) {
	writer.write("#invalid payload reference\n");
	commentOutInstruction = true;
	}
	}

	if (opcode.odexOnly()) {
	if (!isAllowedOdex(opcode)) {
	writer.write("#disallowed odex opcode\n");
	commentOutInstruction = true;
	}
	}

	if (commentOutInstruction) {
	writer.write("#");
	}

	switch (instruction.getOpcode().format) {
	case Format10t:
	writeOpcode(writer);
	writer.write(' ');
	writeTargetLabel(writer);
	break;
	case Format10x:
	if (instruction instanceof UnknownInstruction) {
	writer.write("#unknown opcode: 0x");
	writer.printUnsignedLongAsHex(((UnknownInstruction)instruction).getOriginalOpcode());
	writer.write('\n');
	}
	writeOpcode(writer);
	break;
	case Format11n:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	writer.write(", ");
	writeLiteral(writer);
	break;
	case Format11x:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	break;
	case Format12x:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	writer.write(", ");
	writeSecondRegister(writer);
	break;
	case Format20bc:
	writeOpcode(writer);
	writer.write(' ');
	writer.write(verificationErrorName);
	writer.write(", ");
	writer.write(referenceString);
	break;
	case Format20t:
	case Format30t:
	writeOpcode(writer);
	writer.write(' ');
	writeTargetLabel(writer);
	break;
	case Format21c:
	case Format31c:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	writer.write(", ");
	writer.write(referenceString);
	break;
	case Format21ih:
	case Format21lh:
	case Format21s:
	case Format31i:
	case Format51l:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	writer.write(", ");
	writeLiteral(writer);
	if (instruction.getOpcode().setsWideRegister()) {
	writeCommentIfLikelyDouble(writer);
	} else {
	boolean isResourceId = writeCommentIfResourceId(writer);
	if (!isResourceId) writeCommentIfLikelyFloat(writer);
	}
	break;
	case Format21t:
	case Format31t:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	writer.write(", ");
	writeTargetLabel(writer);
	break;
	case Format22b:
	case Format22s:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	writer.write(", ");
	writeSecondRegister(writer);
	writer.write(", ");
	writeLiteral(writer);
	break;
	case Format22c:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	writer.write(", ");
	writeSecondRegister(writer);
	writer.write(", ");
	writer.write(referenceString);
	break;
	case Format22cs:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	writer.write(", ");
	writeSecondRegister(writer);
	writer.write(", ");
	writeFieldOffset(writer);
	break;
	case Format22t:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	writer.write(", ");
	writeSecondRegister(writer);
	writer.write(", ");
	writeTargetLabel(writer);
	break;
	case Format22x:
	case Format32x:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	writer.write(", ");
	writeSecondRegister(writer);
	break;
	case Format23x:
	writeOpcode(writer);
	writer.write(' ');
	writeFirstRegister(writer);
	writer.write(", ");
	writeSecondRegister(writer);
	writer.write(", ");
	writeThirdRegister(writer);
	break;
	case Format35c:
	writeOpcode(writer);
	writer.write(' ');
	writeInvokeRegisters(writer);
	writer.write(", ");
	writer.write(referenceString);
	break;
	case Format35mi:
	writeOpcode(writer);
	writer.write(' ');
	writeInvokeRegisters(writer);
	writer.write(", ");
	writeInlineIndex(writer);
	break;
	case Format35ms:
	writeOpcode(writer);
	writer.write(' ');
	writeInvokeRegisters(writer);
	writer.write(", ");
	writeVtableIndex(writer);
	break;
	case Format3rc:
	writeOpcode(writer);
	writer.write(' ');
	writeInvokeRangeRegisters(writer);
	writer.write(", ");
	writer.write(referenceString);
	break;
	case Format3rmi:
	writeOpcode(writer);
	writer.write(' ');
	writeInvokeRangeRegisters(writer);
	writer.write(", ");
	writeInlineIndex(writer);
	break;
	case Format3rms:
	writeOpcode(writer);
	writer.write(' ');
	writeInvokeRangeRegisters(writer);
	writer.write(", ");
	writeVtableIndex(writer);
	break;
	case Format45cc:
	writeOpcode(writer);
	writer.write(' ');
	writeInvokeRegisters(writer);
	writer.write(", ");
	writer.write(referenceString);
	writer.write(", ");
	writer.write(referenceString2);
	break;
	case Format4rcc:
	writeOpcode(writer);
	writer.write(' ');
	writeInvokeRangeRegisters(writer);
	writer.write(", ");
	writer.write(referenceString);
	writer.write(", ");
	writer.write(referenceString2);
	break;
	default:
	assert false;
	return false;
	}

	if (commentOutInstruction) {
	writer.write("\nnop");
	}

	return true;
	}

	protected void writeOpcode(IndentingWriter writer) throws IOException {
	writer.write(instruction.getOpcode().name);
	}

	protected void writeTargetLabel(IndentingWriter writer) throws IOException {
	//this method is overridden by OffsetInstructionMethodItem, and should only be called for the formats that
	//have a target
	throw new RuntimeException();
	}

	protected void writeRegister(IndentingWriter writer, int registerNumber) throws IOException {
	methodDef.registerFormatter.writeTo(writer, registerNumber);
	}

	protected void writeFirstRegister(IndentingWriter writer) throws IOException {
	writeRegister(writer, ((OneRegisterInstruction)instruction).getRegisterA());
	}

	protected void writeSecondRegister(IndentingWriter writer) throws IOException {
	writeRegister(writer, ((TwoRegisterInstruction)instruction).getRegisterB());
	}

	protected void writeThirdRegister(IndentingWriter writer) throws IOException {
	writeRegister(writer, ((ThreeRegisterInstruction) instruction).getRegisterC());
	}

	protected void writeInvokeRegisters(IndentingWriter writer) throws IOException {
	FiveRegisterInstruction instruction = (FiveRegisterInstruction)this.instruction;
	final int regCount = instruction.getRegisterCount();

	writer.write('{');
	switch (regCount) {
	case 1:
	writeRegister(writer, instruction.getRegisterC());
	break;
	case 2:
	writeRegister(writer, instruction.getRegisterC());
	writer.write(", ");
	writeRegister(writer, instruction.getRegisterD());
	break;
	case 3:
	writeRegister(writer, instruction.getRegisterC());
	writer.write(", ");
	writeRegister(writer, instruction.getRegisterD());
	writer.write(", ");
	writeRegister(writer, instruction.getRegisterE());
	break;
	case 4:
	writeRegister(writer, instruction.getRegisterC());
	writer.write(", ");
	writeRegister(writer, instruction.getRegisterD());
	writer.write(", ");
	writeRegister(writer, instruction.getRegisterE());
	writer.write(", ");
	writeRegister(writer, instruction.getRegisterF());
	break;
	case 5:
	writeRegister(writer, instruction.getRegisterC());
	writer.write(", ");
	writeRegister(writer, instruction.getRegisterD());
	writer.write(", ");
	writeRegister(writer, instruction.getRegisterE());
	writer.write(", ");
	writeRegister(writer, instruction.getRegisterF());
	writer.write(", ");
	writeRegister(writer, instruction.getRegisterG());
	break;
	}
	writer.write('}');
	}

	protected void writeInvokeRangeRegisters(IndentingWriter writer) throws IOException {
	RegisterRangeInstruction instruction = (RegisterRangeInstruction)this.instruction;

	int regCount = instruction.getRegisterCount();
	if (regCount == 0) {
	writer.write("{}");
	} else {
	int startRegister = instruction.getStartRegister();
	methodDef.registerFormatter.writeRegisterRange(writer, startRegister, startRegister+regCount-1);
	}
	}

	protected void writeLiteral(IndentingWriter writer) throws IOException {
	LongRenderer.writeSignedIntOrLongTo(writer, ((WideLiteralInstruction)instruction).getWideLiteral());
	}

	protected void writeCommentIfLikelyFloat(IndentingWriter writer) throws IOException {
	writeCommentIfLikelyFloat(writer, ((NarrowLiteralInstruction)instruction).getNarrowLiteral());
	}

	protected void writeCommentIfLikelyFloat(IndentingWriter writer, int val) throws IOException {
	if (NumberUtils.isLikelyFloat(val)) {
	writer.write(" # ");
	float fval = Float.intBitsToFloat(val);
	if (fval == Float.POSITIVE_INFINITY)
	writer.write("Float.POSITIVE_INFINITY");
	else if (fval == Float.NEGATIVE_INFINITY)
	writer.write("Float.NEGATIVE_INFINITY");
	else if (Float.isNaN(fval))
	writer.write("Float.NaN");
	else if (fval == Float.MAX_VALUE)
	writer.write("Float.MAX_VALUE");
	else if (fval == (float)Math.PI)
	writer.write("(float)Math.PI");
	else if (fval == (float)Math.E)
	writer.write("(float)Math.E");
	else {
	writer.write(Float.toString(fval));
	writer.write('f');
	}
	}
	}

	protected void writeCommentIfLikelyDouble(IndentingWriter writer) throws IOException {
	writeCommentIfLikelyDouble(writer, ((WideLiteralInstruction)instruction).getWideLiteral());
	}

	protected void writeCommentIfLikelyDouble(IndentingWriter writer, long val) throws IOException {
	if (NumberUtils.isLikelyDouble(val)) {
	writer.write(" # ");
	double dval = Double.longBitsToDouble(val);
	if (dval == Double.POSITIVE_INFINITY)
	writer.write("Double.POSITIVE_INFINITY");
	else if (dval == Double.NEGATIVE_INFINITY)
	writer.write("Double.NEGATIVE_INFINITY");
	else if (Double.isNaN(dval))
	writer.write("Double.NaN");
	else if (dval == Double.MAX_VALUE)
	writer.write("Double.MAX_VALUE");
	else if (dval == Math.PI)
	writer.write("Math.PI");
	else if (dval == Math.E)
	writer.write("Math.E");
	else
	writer.write(Double.toString(dval));
	}
	}

	protected boolean writeCommentIfResourceId(IndentingWriter writer) throws IOException {
	return writeCommentIfResourceId(writer, ((NarrowLiteralInstruction)instruction).getNarrowLiteral());
	}

	protected boolean writeCommentIfResourceId(IndentingWriter writer, int val) throws IOException {
	Map<Integer,String> resourceIds = methodDef.classDef.options.resourceIds;
	String resource = resourceIds.get(Integer.valueOf(val));
	if (resource != null) {
	writer.write(" # ");
	writer.write(resource);
	return true;
	}
	return false;
	}

	protected void writeFieldOffset(IndentingWriter writer) throws IOException {
	writer.write("field@0x");
	writer.printUnsignedLongAsHex(((FieldOffsetInstruction)instruction).getFieldOffset());
	}

	protected void writeInlineIndex(IndentingWriter writer) throws IOException {
	writer.write("inline@");
	writer.printSignedIntAsDec(((InlineIndexInstruction)instruction).getInlineIndex());
	}

	protected void writeVtableIndex(IndentingWriter writer) throws IOException {
	writer.write("vtable@");
	writer.printSignedIntAsDec(((VtableIndexInstruction)instruction).getVtableIndex());
	}
	}