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#4 Classfile - Refactor the wide opcode parser
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@amosshi
amosshi committed Dec 16, 2019
1 parent 949bbeb commit 0d00484
Showing 1 changed file with 43 additions and 46 deletions.
89 changes: 43 additions & 46 deletions FormatCLASS/src/main/java/org/freeinternals/format/classfile/Opcode.java
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Original file line number Diff line number Diff line change
Expand Up @@ -1639,7 +1639,7 @@ protected InstructionParsed parse(final int curPos, final PosDataInputStream pdi
protected InstructionParsed parse(final int curPos, final PosDataInputStream pdis) throws IOException {
InstructionParsed parsed = new InstructionParsed(curPos, this.code);
parsed.cpIndex = pdis.readUnsignedShort();

// Skip 2 zero bytes
BytesTool.skipBytes(pdis, 2);
parsed.opCodeText = this.name();
Expand Down Expand Up @@ -1753,57 +1753,62 @@ protected InstructionParsed parse(final int curPos, final PosDataInputStream pdi
* TODO - Refactor this method
*/
wide(196) {
private List<Integer> WIDE_SINGLE_OPCODES = new ArrayList<Integer>() {
{
add(Opcode.Instruction.iload.code);
add(Opcode.Instruction.lload.code);
add(Opcode.Instruction.fload.code);
add(Opcode.Instruction.dload.code);
add(Opcode.Instruction.aload.code);
add(Opcode.Instruction.istore.code);
add(Opcode.Instruction.lstore.code);
add(Opcode.Instruction.fstore.code);
add(Opcode.Instruction.dstore.code);
add(Opcode.Instruction.astore.code);
add(Opcode.Instruction.ret.code);
}
};

/**
* The target opcode for the {@link Instruction#wide} instruction.
*/
private int wide_opcode;

@Override
protected InstructionParsed parse(final int curPos, final PosDataInputStream pdis) throws IOException {
InstructionParsed parsed = new InstructionParsed(curPos, this.code);
parsed.opCodeText = this.getText_wide(pdis);
return parsed;
}

@Override
String getName() {
return getWideName(Opcode.Instruction.valueOf(this.wide_opcode).name());
}

/**
* Get the name with "wide " prefix. Only applied for {@link #wide}.
*
* @return opcode name with "wide " prefix
*/
String getWideName(String s) {
return Instruction.wide.name() + " " + s;
}

private String getText_wide(final PosDataInputStream pdis) throws IOException {
final int opcode = pdis.readUnsignedByte();
this.wide_opcode = pdis.readUnsignedByte();
String opCodeText;

int shortValue;
int shortValue2;

if (opcode == Opcode.Instruction.iload.code) {
shortValue = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_NUMBER, Instruction.getWideName(Opcode.Instruction.iload.name()), shortValue);
} else if (opcode == Opcode.Instruction.lload.code) {
shortValue = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_NUMBER, Instruction.getWideName(Opcode.Instruction.lload.name()), shortValue);
} else if (opcode == Opcode.Instruction.fload.code) {
shortValue = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_NUMBER, Instruction.getWideName(Opcode.Instruction.fload.name()), shortValue);
} else if (opcode == Opcode.Instruction.dload.code) {
shortValue = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_NUMBER, Instruction.getWideName(Opcode.Instruction.dload.name()), shortValue);
} else if (opcode == Opcode.Instruction.aload.code) {
if (this.WIDE_SINGLE_OPCODES.contains(this.wide_opcode)) {
shortValue = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_NUMBER, Instruction.getWideName(Opcode.Instruction.aload.name()), shortValue);
} else if (opcode == Opcode.Instruction.istore.code) {
shortValue = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_NUMBER, Instruction.getWideName(Opcode.Instruction.istore.name()), shortValue);
} else if (opcode == Opcode.Instruction.lstore.code) {
shortValue = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_NUMBER, Instruction.getWideName(Opcode.Instruction.lstore.name()), shortValue);
} else if (opcode == Opcode.Instruction.fstore.code) {
shortValue = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_NUMBER, Instruction.getWideName(Opcode.Instruction.fstore.name()), shortValue);
} else if (opcode == Opcode.Instruction.dstore.code) {
shortValue = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_NUMBER, Instruction.getWideName(Opcode.Instruction.dstore.name()), shortValue);
} else if (opcode == Opcode.Instruction.astore.code) {
shortValue = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_NUMBER, Instruction.getWideName(Opcode.Instruction.astore.name()), shortValue);
} else if (opcode == Opcode.Instruction.iinc.code) {
opCodeText = String.format(FORMAT_OPCODE_NUMBER, getWideName(Opcode.Instruction.valueOf(this.wide_opcode).name()), shortValue);
} else if (this.wide_opcode == Opcode.Instruction.iinc.code) {
shortValue = pdis.readUnsignedShort();
shortValue2 = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_LOCAL_IINC, Instruction.getWideName(Opcode.Instruction.iinc.name()), shortValue, shortValue2);
} else if (opcode == Opcode.Instruction.ret.code) {
shortValue = pdis.readUnsignedShort();
opCodeText = String.format(FORMAT_OPCODE_NUMBER, Instruction.getWideName(Opcode.Instruction.ret.name()), shortValue);
opCodeText = String.format(FORMAT_OPCODE_LOCAL_IINC, getWideName(Opcode.Instruction.iinc.name()), shortValue, shortValue2);
} else {
opCodeText = String.format("%s [Unknown opcode]", Opcode.Instruction.wide.name());
}
Expand Down Expand Up @@ -1920,6 +1925,7 @@ protected InstructionParsed parse(final int curPos, final PosDataInputStream pdi
* @see #new_
* @see #instanceof_
* @see #reserved
* @see #wide
*/
String getName() {
String name = super.name();
Expand All @@ -1934,15 +1940,6 @@ String getName() {
return name;
}

/**
* Get the name with "wide " prefix. Only applied for {@link #wide}.
*
* @return opcode name with "wide " prefix
*/
static String getWideName(String s) {
return Instruction.wide.name() + " " + s;
}

/**
* Get Opcode name.
*
Expand Down Expand Up @@ -2170,7 +2167,7 @@ public static class InstructionParsed {
* @see Instruction#getName()
*/
public final String opCodeName;

/**
* Text of the {@link #opCode}. In case {@link #opCode} is
* {@link Instruction#wide}, the {@link #opCodeText} contains the
Expand Down

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