Re: [Patch] catch builtin_bswap16 construct

[Segher Boessenkool]

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.

The RTL is  (set (reg:HI) (bswap:HI (reg:HI)))  which then gets
extended for the SI (or DI) function return.  Nothing to see here,
it's a target problem.  Your results look good.


Segher