private static Exp OptimizeBnot(UnopExp exp)
{
switch (exp.Exp)
{
case IntegerExp ie:
{
ie.Val = ~ie.Val;
return(ie);
}
case FloatExp fe:
{
if (LuaMath.FloatToInteger(fe.Val, out var ret))
{
return(new IntegerExp
{
Line = exp.Line,
Val = ~ret
});
}
break;
}
}
return(exp);
}
private static void CgUnopExp(FuncInfo fi, UnopExp node, int a)
{
var b = fi.AllocReg();
CgExp(fi, node.Exp, b, 1);
fi.EmitUnaryOp(node.GetOpCode(), a, b);
fi.FreeReg();
}
private static Exp OptimizeUnm(UnopExp exp)
{
switch (exp.Exp)
{
case IntegerExp ie:
ie.Val = -ie.Val;
return(ie);
case FloatExp fe:
fe.Val = -fe.Val;
return(fe);
default:
return(exp);
}
}
private static Exp OptimizeUnaryOp(UnopExp exp)
{
switch (exp.Op)
{
case ETokenType.OpUnm:
return(OptimizeUnm(exp));
case ETokenType.OpNot:
return(OptimizeNot(exp));
case ETokenType.OpBNot:
return(OptimizeBnot(exp));
default:
return(exp);
}
}
private static Exp OptimizeNot(UnopExp exp)
{
switch (exp.Exp)
{
case NilExp ne:
case FalseExp fe:
return(new TrueExp {
Line = exp.Line
});
case TrueExp te:
case IntegerExp ie:
case FloatExp fe:
case StringExp se:
return(new FalseExp {
Line = exp.Line
});
default:
return(exp);
}
}
private static Exp ParseExp2(Lexer.Lexer lexer)
{
switch (lexer.LookAhead())
{
case ETokenType.OpUnm:
case ETokenType.OpBNot:
case ETokenType.OpLen:
case ETokenType.OpNot:
{
lexer.NextToken(out var line, out var op, out _);
var exp = new UnopExp
{
Line = line,
Op = op,
Exp = ParseExp2(lexer)
};
return(OptimizeUnaryOp(exp));
}
}
return(ParseExp1(lexer));
}
