private static void CgNameExp(FuncInfo fi, NameExp node, int a)
{
var r = fi.SlotOfLocVar(node.Name);
if (r >= 0)
{
fi.EmitMove(a, r);
}
else
{
var idx = fi.IndexOfUpval(node.Name);
if (idx >= 0)
{
fi.EmitGetUpval(a, idx);
}
else
{
var taExp = new TableAccessExp
{
PrefixExp = new NameExp
{
Line = 0,
Name = "_ENV"
},
KeyExp = new StringExp
{
Line = 0,
Str = node.Name
}
};
CgTableAccessExp(fi, taExp, a);
}
}
}
private static void CgTableAccessExp(FuncInfo fi, TableAccessExp node, int a)
{
var b = fi.AllocReg();
CgExp(fi, node.PrefixExp, b, 1);
var c = fi.AllocReg();
CgExp(fi, node.KeyExp, c, 1);
fi.EmitGetTable(a, b, c);
fi.FreeRegs(2);
}
private static Exp FinishPrefixExp(Lexer.Lexer lexer, Exp exp)
{
while (true)
{
switch (lexer.LookAhead())
{
case ETokenType.SepLBracket:
{
lexer.NextToken(out _, out _, out _);
var keyExp = ParseExp(lexer);
lexer.NextTokenOfKind(ETokenType.SepRBracket, out _, out _);
exp = new TableAccessExp
{
LastLine = lexer.Line,
PrefixExp = exp,
KeyExp = keyExp
};
break;
}
case ETokenType.SepDot:
{
lexer.NextToken(out _, out _, out _);
lexer.NextIdentifier(out var line, out var name);
var keyExp = new StringExp
{
Line = line,
Str = name
};
exp = new TableAccessExp
{
LastLine = line,
PrefixExp = exp,
KeyExp = keyExp
};
break;
}
case ETokenType.SepColon:
case ETokenType.SepLParen:
case ETokenType.SepLCurly:
case ETokenType.String:
{
exp = FinishFuncCallExp(lexer, exp);
break;
}
default:
return(exp);
}
}
}
private static void ParseFuncName(Lexer.Lexer lexer, out Exp exp, out bool hasColon)
{
hasColon = false;
lexer.NextIdentifier(out var line, out var name);
exp = new NameExp {
Line = line, Name = name
};
while (lexer.LookAhead() == ETokenType.SepDot)
{
lexer.NextToken(out _, out _, out _);
lexer.NextIdentifier(out line, out name);
var idx = new StringExp {
Line = line, Str = name
};
exp = new TableAccessExp
{
LastLine = line,
KeyExp = idx,
PrefixExp = exp,
};
}
if (lexer.LookAhead() == ETokenType.SepColon)
{
lexer.NextToken(out _, out _, out _);
lexer.NextIdentifier(out line, out name);
var idx = new StringExp {
Line = line, Str = name
};
exp = new TableAccessExp
{
LastLine = line,
PrefixExp = exp,
KeyExp = idx,
};
hasColon = true;
}
}
