Re: [Sdcc-user] Peephole 132 ...

[Kai V. <volkmar@s.netic.de>]

Michael Schmitt wrote (shortened):
 
>  ...
> I quick view into the lst file shows that the sjmp is now a ljmp.
> 
> so could it be that
>   0764 80 81              2215  sjmp 00179$
>   07E7                    2283 00179$:
> is wrong ?
> 0x7E7-0x764 - 2byte code = 0x81
> but doesn't 0x81 mean a jump backwards to 0x6E3 or so ? this would
> explain something ?
> i am not shure but i thought that it is only possible to do a short jump
> -128 .. +127
> and 0x81 is negative ....
> 
> Ah, one last thing to mention. The sdcc-built is the same as the one i
> have sent to the OKR. i made it from the cvs sources august 28. But
> earlier versions also showed that.
> 
> Dipl.-Ing. (FH) Michael Schmitt
> Baumer Ident GmbH
> Entwicklung / Development Department
> Hertzstr. 10
> D-69469 Weinheim
> Deutschland / Germany
> Tel. +49 (0) 6201 9957 - 30
> Fax. +49 (0) 6201 9957 - 99
> E-Mail : msc...@ba...
> Web: http://www.baumerident.com
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Hi Michael,

of course you're right. Because the 8051 SJMP instruction is of the 2
bytes (1 operand) type, it won't allow jumps wider than the -128...127
bytes range. Maybe it's easy to find the bug in the optimizer rules.

Kai