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Dynamic scripting for the JVM
/*
* Copyright (C) 2011 The Android Open Source Project
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.snapscript.dx.io.instructions;
import java.io.EOFException;
import org.snapscript.dex.DexException;
import org.snapscript.dx.io.IndexType;
import org.snapscript.dx.io.OpcodeInfo;
import org.snapscript.dx.io.Opcodes;
import org.snapscript.dx.util.Hex;
/**
* Representation of an instruction format, which knows how to decode into
* and encode from instances of {@link DecodedInstruction}.
*/
public enum InstructionCodec {
FORMAT_00X() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
return new ZeroRegisterDecodedInstruction(
this, opcodeUnit, 0, null,
0, 0L);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(insn.getOpcodeUnit());
}
},
FORMAT_10X() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int literal = byte1(opcodeUnit); // should be zero
return new ZeroRegisterDecodedInstruction(
this, opcode, 0, null,
0, literal);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(insn.getOpcodeUnit());
}
},
FORMAT_12X() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = nibble2(opcodeUnit);
int b = nibble3(opcodeUnit);
return new TwoRegisterDecodedInstruction(
this, opcode, 0, null,
0, 0L,
a, b);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(
codeUnit(insn.getOpcodeUnit(),
makeByte(insn.getA(), insn.getB())));
}
},
FORMAT_11N() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = nibble2(opcodeUnit);
int literal = (nibble3(opcodeUnit) << 28) >> 28; // sign-extend
return new OneRegisterDecodedInstruction(
this, opcode, 0, null,
0, literal,
a);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(
codeUnit(insn.getOpcodeUnit(),
makeByte(insn.getA(), insn.getLiteralNibble())));
}
},
FORMAT_11X() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
return new OneRegisterDecodedInstruction(
this, opcode, 0, null,
0, 0L,
a);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(codeUnit(insn.getOpcode(), insn.getA()));
}
},
FORMAT_10T() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int baseAddress = in.cursor() - 1;
int opcode = byte0(opcodeUnit);
int target = (byte) byte1(opcodeUnit); // sign-extend
return new ZeroRegisterDecodedInstruction(
this, opcode, 0, null,
baseAddress + target, 0L);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
int relativeTarget = insn.getTargetByte(out.cursor());
out.write(codeUnit(insn.getOpcode(), relativeTarget));
}
},
FORMAT_20T() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int baseAddress = in.cursor() - 1;
int opcode = byte0(opcodeUnit);
int literal = byte1(opcodeUnit); // should be zero
int target = (short) in.read(); // sign-extend
return new ZeroRegisterDecodedInstruction(
this, opcode, 0, null,
baseAddress + target, literal);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
short relativeTarget = insn.getTargetUnit(out.cursor());
out.write(insn.getOpcodeUnit(), relativeTarget);
}
},
FORMAT_20BC() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
// Note: We use the literal field to hold the decoded AA value.
int opcode = byte0(opcodeUnit);
int literal = byte1(opcodeUnit);
int index = in.read();
return new ZeroRegisterDecodedInstruction(
this, opcode, index, IndexType.VARIES,
0, literal);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(
codeUnit(insn.getOpcode(), insn.getLiteralByte()),
insn.getIndexUnit());
}
},
FORMAT_22X() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
int b = in.read();
return new TwoRegisterDecodedInstruction(
this, opcode, 0, null,
0, 0L,
a, b);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(
codeUnit(insn.getOpcode(), insn.getA()),
insn.getBUnit());
}
},
FORMAT_21T() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int baseAddress = in.cursor() - 1;
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
int target = (short) in.read(); // sign-extend
return new OneRegisterDecodedInstruction(
this, opcode, 0, null,
baseAddress + target, 0L,
a);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
short relativeTarget = insn.getTargetUnit(out.cursor());
out.write(codeUnit(insn.getOpcode(), insn.getA()), relativeTarget);
}
},
FORMAT_21S() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
int literal = (short) in.read(); // sign-extend
return new OneRegisterDecodedInstruction(
this, opcode, 0, null,
0, literal,
a);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(
codeUnit(insn.getOpcode(), insn.getA()),
insn.getLiteralUnit());
}
},
FORMAT_21H() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
long literal = (short) in.read(); // sign-extend
/*
* Format 21h decodes differently depending on the opcode,
* because the "signed hat" might represent either a 32-
* or 64- bit value.
*/
literal <<= (opcode == Opcodes.CONST_HIGH16) ? 16 : 48;
return new OneRegisterDecodedInstruction(
this, opcode, 0, null,
0, literal,
a);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
// See above.
int opcode = insn.getOpcode();
int shift = (opcode == Opcodes.CONST_HIGH16) ? 16 : 48;
short literal = (short) (insn.getLiteral() >> shift);
out.write(codeUnit(opcode, insn.getA()), literal);
}
},
FORMAT_21C() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
int index = in.read();
IndexType indexType = OpcodeInfo.getIndexType(opcode);
return new OneRegisterDecodedInstruction(
this, opcode, index, indexType,
0, 0L,
a);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(
codeUnit(insn.getOpcode(), insn.getA()),
insn.getIndexUnit());
}
},
FORMAT_23X() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
int bc = in.read();
int b = byte0(bc);
int c = byte1(bc);
return new ThreeRegisterDecodedInstruction(
this, opcode, 0, null,
0, 0L,
a, b, c);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(
codeUnit(insn.getOpcode(), insn.getA()),
codeUnit(insn.getB(), insn.getC()));
}
},
FORMAT_22B() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
int bc = in.read();
int b = byte0(bc);
int literal = (byte) byte1(bc); // sign-extend
return new TwoRegisterDecodedInstruction(
this, opcode, 0, null,
0, literal,
a, b);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(
codeUnit(insn.getOpcode(), insn.getA()),
codeUnit(insn.getB(),
insn.getLiteralByte()));
}
},
FORMAT_22T() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int baseAddress = in.cursor() - 1;
int opcode = byte0(opcodeUnit);
int a = nibble2(opcodeUnit);
int b = nibble3(opcodeUnit);
int target = (short) in.read(); // sign-extend
return new TwoRegisterDecodedInstruction(
this, opcode, 0, null,
baseAddress + target, 0L,
a, b);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
short relativeTarget = insn.getTargetUnit(out.cursor());
out.write(
codeUnit(insn.getOpcode(),
makeByte(insn.getA(), insn.getB())),
relativeTarget);
}
},
FORMAT_22S() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = nibble2(opcodeUnit);
int b = nibble3(opcodeUnit);
int literal = (short) in.read(); // sign-extend
return new TwoRegisterDecodedInstruction(
this, opcode, 0, null,
0, literal,
a, b);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(
codeUnit(insn.getOpcode(),
makeByte(insn.getA(), insn.getB())),
insn.getLiteralUnit());
}
},
FORMAT_22C() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = nibble2(opcodeUnit);
int b = nibble3(opcodeUnit);
int index = in.read();
IndexType indexType = OpcodeInfo.getIndexType(opcode);
return new TwoRegisterDecodedInstruction(
this, opcode, index, indexType,
0, 0L,
a, b);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(
codeUnit(insn.getOpcode(),
makeByte(insn.getA(), insn.getB())),
insn.getIndexUnit());
}
},
FORMAT_22CS() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = nibble2(opcodeUnit);
int b = nibble3(opcodeUnit);
int index = in.read();
return new TwoRegisterDecodedInstruction(
this, opcode, index, IndexType.FIELD_OFFSET,
0, 0L,
a, b);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(
codeUnit(insn.getOpcode(),
makeByte(insn.getA(), insn.getB())),
insn.getIndexUnit());
}
},
FORMAT_30T() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int baseAddress = in.cursor() - 1;
int opcode = byte0(opcodeUnit);
int literal = byte1(opcodeUnit); // should be zero
int target = in.readInt();
return new ZeroRegisterDecodedInstruction(
this, opcode, 0, null,
baseAddress + target, literal);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
int relativeTarget = insn.getTarget(out.cursor());
out.write(insn.getOpcodeUnit(),
unit0(relativeTarget), unit1(relativeTarget));
}
},
FORMAT_32X() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int literal = byte1(opcodeUnit); // should be zero
int a = in.read();
int b = in.read();
return new TwoRegisterDecodedInstruction(
this, opcode, 0, null,
0, literal,
a, b);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
out.write(insn.getOpcodeUnit(), insn.getAUnit(), insn.getBUnit());
}
},
FORMAT_31I() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
int literal = in.readInt();
return new OneRegisterDecodedInstruction(
this, opcode, 0, null,
0, literal,
a);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
int literal = insn.getLiteralInt();
out.write(
codeUnit(insn.getOpcode(), insn.getA()),
unit0(literal),
unit1(literal));
}
},
FORMAT_31T() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int baseAddress = in.cursor() - 1;
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
int target = baseAddress + in.readInt();
/*
* Switch instructions need to "forward" their addresses to their
* payload target instructions.
*/
switch (opcode) {
case Opcodes.PACKED_SWITCH:
case Opcodes.SPARSE_SWITCH: {
in.setBaseAddress(target, baseAddress);
break;
}
}
return new OneRegisterDecodedInstruction(
this, opcode, 0, null,
target, 0L,
a);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
int relativeTarget = insn.getTarget(out.cursor());
out.write(
codeUnit(insn.getOpcode(), insn.getA()),
unit0(relativeTarget), unit1(relativeTarget));
}
},
FORMAT_31C() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
int index = in.readInt();
IndexType indexType = OpcodeInfo.getIndexType(opcode);
return new OneRegisterDecodedInstruction(
this, opcode, index, indexType,
0, 0L,
a);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
int index = insn.getIndex();
out.write(
codeUnit(insn.getOpcode(), insn.getA()),
unit0(index),
unit1(index));
}
},
FORMAT_35C() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
return decodeRegisterList(this, opcodeUnit, in);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
encodeRegisterList(insn, out);
}
},
FORMAT_35MS() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
return decodeRegisterList(this, opcodeUnit, in);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
encodeRegisterList(insn, out);
}
},
FORMAT_35MI() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
return decodeRegisterList(this, opcodeUnit, in);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
encodeRegisterList(insn, out);
}
},
FORMAT_3RC() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
return decodeRegisterRange(this, opcodeUnit, in);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
encodeRegisterRange(insn, out);
}
},
FORMAT_3RMS() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
return decodeRegisterRange(this, opcodeUnit, in);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
encodeRegisterRange(insn, out);
}
},
FORMAT_3RMI() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
return decodeRegisterRange(this, opcodeUnit, in);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
encodeRegisterRange(insn, out);
}
},
FORMAT_51L() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int opcode = byte0(opcodeUnit);
int a = byte1(opcodeUnit);
long literal = in.readLong();
return new OneRegisterDecodedInstruction(
this, opcode, 0, null,
0, literal,
a);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
long literal = insn.getLiteral();
out.write(
codeUnit(insn.getOpcode(), insn.getA()),
unit0(literal),
unit1(literal),
unit2(literal),
unit3(literal));
}
},
FORMAT_PACKED_SWITCH_PAYLOAD() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int baseAddress = in.baseAddressForCursor() - 1; // already read opcode
int size = in.read();
int firstKey = in.readInt();
int[] targets = new int[size];
for (int i = 0; i < size; i++) {
targets[i] = baseAddress + in.readInt();
}
return new PackedSwitchPayloadDecodedInstruction(
this, opcodeUnit, firstKey, targets);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
PackedSwitchPayloadDecodedInstruction payload =
(PackedSwitchPayloadDecodedInstruction) insn;
int[] targets = payload.getTargets();
int baseAddress = out.baseAddressForCursor();
out.write(payload.getOpcodeUnit());
out.write(asUnsignedUnit(targets.length));
out.writeInt(payload.getFirstKey());
for (int target : targets) {
out.writeInt(target - baseAddress);
}
}
},
FORMAT_SPARSE_SWITCH_PAYLOAD() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int baseAddress = in.baseAddressForCursor() - 1; // already read opcode
int size = in.read();
int[] keys = new int[size];
int[] targets = new int[size];
for (int i = 0; i < size; i++) {
keys[i] = in.readInt();
}
for (int i = 0; i < size; i++) {
targets[i] = baseAddress + in.readInt();
}
return new SparseSwitchPayloadDecodedInstruction(
this, opcodeUnit, keys, targets);
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
SparseSwitchPayloadDecodedInstruction payload =
(SparseSwitchPayloadDecodedInstruction) insn;
int[] keys = payload.getKeys();
int[] targets = payload.getTargets();
int baseAddress = out.baseAddressForCursor();
out.write(payload.getOpcodeUnit());
out.write(asUnsignedUnit(targets.length));
for (int key : keys) {
out.writeInt(key);
}
for (int target : targets) {
out.writeInt(target - baseAddress);
}
}
},
FORMAT_FILL_ARRAY_DATA_PAYLOAD() {
@Override public DecodedInstruction decode(int opcodeUnit,
CodeInput in) throws EOFException {
int elementWidth = in.read();
int size = in.readInt();
switch (elementWidth) {
case 1: {
byte[] array = new byte[size];
boolean even = true;
for (int i = 0, value = 0; i < size; i++, even = !even) {
if (even) {
value = in.read();
}
array[i] = (byte) (value & 0xff);
value >>= 8;
}
return new FillArrayDataPayloadDecodedInstruction(
this, opcodeUnit, array);
}
case 2: {
short[] array = new short[size];
for (int i = 0; i < size; i++) {
array[i] = (short) in.read();
}
return new FillArrayDataPayloadDecodedInstruction(
this, opcodeUnit, array);
}
case 4: {
int[] array = new int[size];
for (int i = 0; i < size; i++) {
array[i] = in.readInt();
}
return new FillArrayDataPayloadDecodedInstruction(
this, opcodeUnit, array);
}
case 8: {
long[] array = new long[size];
for (int i = 0; i < size; i++) {
array[i] = in.readLong();
}
return new FillArrayDataPayloadDecodedInstruction(
this, opcodeUnit, array);
}
}
throw new DexException("bogus element_width: "
+ Hex.u2(elementWidth));
}
@Override public void encode(DecodedInstruction insn, CodeOutput out) {
FillArrayDataPayloadDecodedInstruction payload =
(FillArrayDataPayloadDecodedInstruction) insn;
short elementWidth = payload.getElementWidthUnit();
Object data = payload.getData();
out.write(payload.getOpcodeUnit());
out.write(elementWidth);
out.writeInt(payload.getSize());
switch (elementWidth) {
case 1: out.write((byte[]) data); break;
case 2: out.write((short[]) data); break;
case 4: out.write((int[]) data); break;
case 8: out.write((long[]) data); break;
default: {
throw new DexException("bogus element_width: "
+ Hex.u2(elementWidth));
}
}
}
};
/**
* Decodes an instruction specified by the given opcode unit, reading
* any required additional code units from the given input source.
*/
public abstract DecodedInstruction decode(int opcodeUnit, CodeInput in)
throws EOFException;
/**
* Encodes the given instruction.
*/
public abstract void encode(DecodedInstruction insn, CodeOutput out);
/**
* Helper method that decodes any of the register-list formats.
*/
private static DecodedInstruction decodeRegisterList(
InstructionCodec format, int opcodeUnit, CodeInput in)
throws EOFException {
int opcode = byte0(opcodeUnit);
int e = nibble2(opcodeUnit);
int registerCount = nibble3(opcodeUnit);
int index = in.read();
int abcd = in.read();
int a = nibble0(abcd);
int b = nibble1(abcd);
int c = nibble2(abcd);
int d = nibble3(abcd);
IndexType indexType = OpcodeInfo.getIndexType(opcode);
// TODO: Having to switch like this is less than ideal.
switch (registerCount) {
case 0:
return new ZeroRegisterDecodedInstruction(
format, opcode, index, indexType,
0, 0L);
case 1:
return new OneRegisterDecodedInstruction(
format, opcode, index, indexType,
0, 0L,
a);
case 2:
return new TwoRegisterDecodedInstruction(
format, opcode, index, indexType,
0, 0L,
a, b);
case 3:
return new ThreeRegisterDecodedInstruction(
format, opcode, index, indexType,
0, 0L,
a, b, c);
case 4:
return new FourRegisterDecodedInstruction(
format, opcode, index, indexType,
0, 0L,
a, b, c, d);
case 5:
return new FiveRegisterDecodedInstruction(
format, opcode, index, indexType,
0, 0L,
a, b, c, d, e);
}
throw new DexException("bogus registerCount: "
+ Hex.uNibble(registerCount));
}
/**
* Helper method that encodes any of the register-list formats.
*/
private static void encodeRegisterList(DecodedInstruction insn,
CodeOutput out) {
out.write(codeUnit(insn.getOpcode(),
makeByte(insn.getE(), insn.getRegisterCount())),
insn.getIndexUnit(),
codeUnit(insn.getA(), insn.getB(), insn.getC(), insn.getD()));
}
/**
* Helper method that decodes any of the three-unit register-range formats.
*/
private static DecodedInstruction decodeRegisterRange(
InstructionCodec format, int opcodeUnit, CodeInput in)
throws EOFException {
int opcode = byte0(opcodeUnit);
int registerCount = byte1(opcodeUnit);
int index = in.read();
int a = in.read();
IndexType indexType = OpcodeInfo.getIndexType(opcode);
return new RegisterRangeDecodedInstruction(
format, opcode, index, indexType,
0, 0L,
a, registerCount);
}
/**
* Helper method that encodes any of the three-unit register-range formats.
*/
private static void encodeRegisterRange(DecodedInstruction insn,
CodeOutput out) {
out.write(codeUnit(insn.getOpcode(), insn.getRegisterCount()),
insn.getIndexUnit(),
insn.getAUnit());
}
private static short codeUnit(int lowByte, int highByte) {
if ((lowByte & ~0xff) != 0) {
throw new IllegalArgumentException("bogus lowByte");
}
if ((highByte & ~0xff) != 0) {
throw new IllegalArgumentException("bogus highByte");
}
return (short) (lowByte | (highByte << 8));
}
private static short codeUnit(int nibble0, int nibble1, int nibble2,
int nibble3) {
if ((nibble0 & ~0xf) != 0) {
throw new IllegalArgumentException("bogus nibble0");
}
if ((nibble1 & ~0xf) != 0) {
throw new IllegalArgumentException("bogus nibble1");
}
if ((nibble2 & ~0xf) != 0) {
throw new IllegalArgumentException("bogus nibble2");
}
if ((nibble3 & ~0xf) != 0) {
throw new IllegalArgumentException("bogus nibble3");
}
return (short) (nibble0 | (nibble1 << 4)
| (nibble2 << 8) | (nibble3 << 12));
}
private static int makeByte(int lowNibble, int highNibble) {
if ((lowNibble & ~0xf) != 0) {
throw new IllegalArgumentException("bogus lowNibble");
}
if ((highNibble & ~0xf) != 0) {
throw new IllegalArgumentException("bogus highNibble");
}
return lowNibble | (highNibble << 4);
}
private static short asUnsignedUnit(int value) {
if ((value & ~0xffff) != 0) {
throw new IllegalArgumentException("bogus unsigned code unit");
}
return (short) value;
}
private static short unit0(int value) {
return (short) value;
}
private static short unit1(int value) {
return (short) (value >> 16);
}
private static short unit0(long value) {
return (short) value;
}
private static short unit1(long value) {
return (short) (value >> 16);
}
private static short unit2(long value) {
return (short) (value >> 32);
}
private static short unit3(long value) {
return (short) (value >> 48);
}
private static int byte0(int value) {
return value & 0xff;
}
private static int byte1(int value) {
return (value >> 8) & 0xff;
}
private static int byte2(int value) {
return (value >> 16) & 0xff;
}
private static int byte3(int value) {
return value >>> 24;
}
private static int nibble0(int value) {
return value & 0xf;
}
private static int nibble1(int value) {
return (value >> 4) & 0xf;
}
private static int nibble2(int value) {
return (value >> 8) & 0xf;
}
private static int nibble3(int value) {
return (value >> 12) & 0xf;
}
}