On Thu, 9 Jul 2015, Marek Polacek wrote:
> On Tue, Jul 07, 2015 at 07:47:50AM +0200, Marc Glisse wrote:
> > On Tue, 7 Jul 2015, Prathamesh Kulkarni wrote:
> >
> > >+/* a * (1 << b) -> a << b */
> > >+(simplify
> > >+ (mult:c @a (lshift integer_onep @b))
> > >+ (if (!FLOAT_TYPE_P (type))
> > >+ (lshift @a @b)))
>
> Just a nit: the last line is wrongly formatted.
>
> > The test FLOAT_TYPE_P seems unnecessary, 'type' is (up to a useless
> > conversion) the result of a shift, so integer, fixed-point or vector. Its
> > lhs is integer_onep, which rules out fixed-point.
>
> Right.
>
> > (I think it is the first pattern using @letter and not @number)
>
> Yea, I think we should be consistent and use @0 and @1 here.
I've added support for non-digit names to allow more descriptive
patterns. Like when we have
/* Fold (X << C1) & C2 into (X << C1) & (C2 | ((1 << C1) - 1))
(X >> C1) & C2 into (X >> C1) & (C2 | ~((type) -1 >> C1))
if the new mask might be further optimized. */
(for shift (lshift rshift)
(simplify
(bit_and (convert?@4 (shift@5 (convert1?@3 @0) INTEGER_CST@1))
INTEGER_CST@2)
using @andop2 instead of @2 and @shift instead of @5 (etc.) might
make the following code easier to follow.
That everything uses digits right now is historic mostly (and
my habit of using digits just because I got used to it).
But yes, with @a, @b vs. @0, @1 we should standardize on something
(digits).
Richard.
