private Code readEmpty(
int opcode,
boolean wideBase,
boolean wideRest,
int offset,
HashMap<Integer, Code.Label> labels)
throws IOException {
switch (opcode) {
case Code.OPCODE_const:
{
int target = readBase(wideBase);
int idx = readRest(wideRest);
Constant c = constantPool[idx];
return Code.Const(target, c);
}
case Code.OPCODE_goto:
{
int target = readTarget(wideRest, offset);
Code.Label lab = findLabel(target, labels);
return Code.Goto(lab.label);
}
case Code.OPCODE_nop:
return Code.Nop;
case Code.OPCODE_returnv:
return Code.Return();
}
throw new RuntimeException("unknown opcode encountered (" + opcode + ")");
}
private Code readUnaryOp(
int opcode,
boolean wideBase,
boolean wideRest,
int offset,
HashMap<Integer, Code.Label> labels)
throws IOException {
int operand = readBase(wideBase);
int typeIdx = readRest(wideRest);
Type type = typePool[typeIdx];
switch (opcode) {
case Code.OPCODE_debug:
return Code.Debug(operand);
case Code.OPCODE_ifis:
{
int resultIdx = readRest(wideRest);
Type result = typePool[resultIdx];
int target = readTarget(wideRest, offset);
Code.Label l = findLabel(target, labels);
return Code.IfIs(type, operand, result, l.label);
}
case Code.OPCODE_throw:
return Code.Throw(type, operand);
case Code.OPCODE_return:
return Code.Return(type, operand);
case Code.OPCODE_switch:
{
ArrayList<Pair<Constant, String>> cases = new ArrayList<Pair<Constant, String>>();
int target = readTarget(wideRest, offset);
Code.Label defaultLabel = findLabel(target, labels);
int nCases = readRest(wideRest);
for (int i = 0; i != nCases; ++i) {
int constIdx = readRest(wideRest);
Constant constant = constantPool[constIdx];
target = readTarget(wideRest, offset);
Code.Label l = findLabel(target, labels);
cases.add(new Pair<Constant, String>(constant, l.label));
}
return Code.Switch(type, operand, defaultLabel.label, cases);
}
}
throw new RuntimeException("unknown opcode encountered (" + opcode + ")");
}