[PATCH][RFC] Force predicate computations to separate stmts

[Richard Guenther]

On Fri, 13 Aug 2010, Diego Novillo wrote:

> On 10-08-13 11:12 , Richard Guenther wrote:
> 
> > This helps streamlining the code and allows for example value-numbering
> > to do sth with these predicates (and eventually drive jump-threading
> > from it).
> 
> Nice!  This ought to help simplify VRP too.  We can move the assertions right
> after the assignments and remove the code that inserts assertions at the top
> of if-then-else blocks.

You still will have asserts 'on edges' - otherwise you don't know
if the predicate is true or false.

> > But - I'm fishing for comments (as usual) on this GIMPLE IL change.
> 
> It's an obvious and useful cleanup.  Thanks.  I have not looked at the patch,
> but I presume that it's perfectly sensible and tedious.

Heh.

> Any changes in memory usage?

I didn't yet measure memory usage or compile time (nor did I look at
all testcases that now fail).  But I would expect memory usage to
go up, not down (one gimple-assign compared to one less operand slot).

Oh, and as a followup a RHS COND_EXPR would now fit in GIMPLE_TERNARY_RHS.

Richard.