Z80 sdasz80 use of .allow_undocumented directive

[Andreas Ziermann]

The .allow_undocumented allows the use of the IYL registers, like LD A,IYL. But looking into the code there seems a problem. The directive only works for .z180 targets. But except the opcode cycle table, there is no direct depedency to the .z180 target.

It seems like a bug or at least not intentional. The statement before the switch will not allow the use of undocumented instructions. How does the compiler can make use of it?

z90mch:
     #define X_Z80 0  -> mchtyp
    #define X_HD64 1 -> mchtyp 
    #define S_CPU 83  -> rf
    #define X_UNDOCD 89 ->rf

        if (!mchtyp && rf>S_CPU) //remove???
                rf = 0;
        switch (rf)

Would it be possible to allow undocumented instruction also for Z80 Targets and remove that line?

[Philipp Klaus Krause]

I suggest to file feature request or bug report.

Philipp

[Andreas Ziermann]

Thanks so far. The second part of the question was about the compiler. There was a discussion before to make use of those opcode during compilation. Especially one opcode JMP (IY) seems meaningful.
How far is the discussion about using those opcode?

[Philipp Klaus Krause]

SDCC does use jp (iy), but it is not an undocumented opcode.

Philipp