Re: Tree-SSA self checking infrastructure

[Jan Hubicka <hubicka at ucw dot cz>]

> For non-pointer integral types the rules are trivial (and in fact they are
> symmetric and transitive -- it's only pointers that can't be made
> transitive and symmetric).
> 
> The nop conversion is consider useless if
> 
>   same types
> 
>   or
> 
>   same type main variant
> 
>   or
> 
>   same modes && same signedness && same precision
> 
> 
> The problem you're trying to solve isn't necessarily solvable because
> you don't know what the expression's original type was.  ie, given an
> expr, you know its current type, but you don't know the original type
> of the expression.

I am still in dark here.  Can you give me some example of pointer types
where we don't want transitivity? What abut symmetricity?

Honza