private Expression RewriteExtract(Domain domain, Expression expression, MachineOperand[] operands)
{
var dt = PrimitiveType.Create(domain, operands[0].Width.BitSize);
if (operands[1] is RegisterPairOperand pair)
{
var offset = binder.EnsureRegister(pair.LowRegister);
var width = binder.EnsureRegister(pair.HighRegister);
return(m.And(
m.Shl(expression, offset),
m.ISub(m.Shl(Constant.UInt64(1), width), 1)));
}
else
{
var width = ((ImmediateOperand)operands[2]).Value.ToInt32();
var offset = ((ImmediateOperand)operands[1]).Value.ToInt32();
var dtSlice = PrimitiveType.CreateBitSlice(width);
var slice = m.Slice(dtSlice, expression, offset);
return(m.Convert(slice, dtSlice, dt));
}
}
public Slice Slice(Expression value, int bitOffset, int bitlength)
{
var type = PrimitiveType.CreateBitSlice(bitlength);
return(new Slice(type, value, bitOffset));
}