Subj : TP 7.0 pointer passing convension
To   : Anton Shepelev
From : Anton Shepelev
Date : Sun Feb 16 2020 22:12:54

I wrote:

> Here  is a fixed version, without redundant opera-
> tions and with single-byte write:
>
> procedure AtoB(a: byte; var b: byte);
> begin asm
>    MOV   ES,  [BP+2]  { store segment of b in ES }
>    MOV   DI,  [BP+4]  { store offset  of b in DI }
>    MOV   AX,  [BP+8]  { store a in AX            }
>    MOV  [DI],  AL     { assign AX to a           }
> end end;

Problem solved.  Here is the correct code in TP  as-
sembly:

procedure AtoBRef(a: byte; var b: byte);
begin asm
   MOV   DI,     [BP+4]  { store offset  of b in DI }
   MOV   ES,     [BP+6]  { store segment of b in ES }
   MOV   AX,     [BP+8]  { store a in AX            }
   MOV  [ES:DI],  AL     { assign AX to a           }
end end;

It works as advertised.

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 * Origin: nntps://fidonews.mine.nu - Lake Ylo - Finland (2:221/360.0)

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