Small poll

Peter Lund peter@REDACTED
Thu Dec 11 11:19:55 CET 2003


If the effort (in sence of valuable time) already has been made,
then it is obviously a good thing to have it doing 2 by default
and 3 by adding some compiler directive.

Erik Stenman wrote:
> You must be kidding, right?
>
> As it is now the compiler always does constant propagation and folding.
> If you write:
>   A = 1 + 2,
> you get
>   A = 3,
> in the compiled beam code.
> (These types of expressions do come up, especially if you are using
> macros...)
>
> The problem is that if you write
>   a + 1,
> then the compiler has to spend extra time compiling the expression,
> handling the
> special case that constant folding does not work, and produce larger
> code than necessary.
>
>> I would not like having anyone wasting their valuable time
>> improving the compiler to catch this
>
> This already has to be cached and handled by the compiler.
>
>> and also wasting more
>> CPU power on everyones computer when compiling.
>
> More CPU power is probably used today in order to 'fix' this
> special case, at least for native code.
>
> Erik






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