On Mon, Jun 23, 2014 at 10:18:16AM +0200, Richard Biener wrote:
> > --- a/gcc/tree-ssa-math-opts.c
> > +++ b/gcc/tree-ssa-math-opts.c
> > @@ -1741,6 +1741,8 @@ find_bswap_1 (gimple stmt, struct symbolic_number *n,
> > int limit)
> > if (n->size % BITS_PER_UNIT != 0)
> > return NULL_TREE;
> > n->size /= BITS_PER_UNIT;
> > + if (n->size > (int)sizeof (unsigned HOST_WIDEST_INT))
> > + return NULL_TREE;
This looks wrong, while the bswap pass is guarded with BITS_PER_UNIT == 8
check (i.e. target), you don't know of HOST_BITS_PER_CHAR is 8.
I'd move the test before the division by BITS_PER_UNIT, and compare
against HOST_BITS_PER_WIDEST_INT.
> > n->n = (sizeof (HOST_WIDEST_INT) < 8 ? 0 :
> > (unsigned HOST_WIDEST_INT)0x08070605 << 32 | 0x04030201);
> >
> > @@ -1781,6 +1783,8 @@ find_bswap_1 (gimple stmt, struct symbolic_number *n,
> > int limit)
> > type_size = TYPE_PRECISION (gimple_expr_type (stmt));
> > if (type_size % BITS_PER_UNIT != 0)
> > return NULL_TREE;
> > + if (type_size > (int)HOST_BITS_PER_WIDEST_INT)
> > + return NULL_TREE;
> >
> > if (type_size / BITS_PER_UNIT < (int)(sizeof (HOST_WIDEST_INT)))
> > {
Similarly here.
BTW, the formatting is wrong too, the (int) cast should be followed by space.
Jakub
