[fpc-devel] optimizing the peephole optimizer?

[Ralf Quint]

On 1/21/2014 4:23 PM, Martin Frb wrote:
Sorry, but those two code blocks are NOT identical as you claim.
At least in the snippets below, GetNextInstruction is called at least 
twice in the OLD snippet, not only once as your supposed NEW snippet 
does. It is called once for either the ffo1 or the ffo2 case and again, 
for the the ffo3 case which is executed after either ffo1 or ffo2.
>
> NEW:
>
> If GetNextInstruction(p, hp1) then Begin
>   if ffo1 then
>     else
>       if ffo2  then
>       ;
>   if ffo3 then
> end;
>
> OLD:
>
>   if ffo1 and
>       GetNextInstruction(p, hp1) then
>     else
>       if ffo2   and
>           GetNextInstruction(p, hp1) then
>       ;
>   if ffo3 and
>      GetNextInstruction(p, hp1) then
>
>
>
> _______________________________________________
> fpc-devel maillist  -  fpc-devel at lists.freepascal.org
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