[Patch] catch builtin_bswap16 construct

[Christophe Lyon]

On 25 September 2012 07:00, Segher Boessenkool
<segher@kernel.crashing.org> wrote:
> Christophe, it looks like the zero-extend in the unsigned case is not
> needed on any target?  Assuming the shifts are at least SImode, of
> course (I'm too lazy to check, sorry).
>

It's also present when compiling:
unsigned short swapu16(unsigned short x) {
     return __builtin_bswap16(x);
}

so it's not directly caused by my patch I think.

We have to look at the __builtin_bswap16 expansion with an unsigned argument.

Christophe.