https://gcc.gnu.org/bugzilla/show_bug.cgi?id=67413
Andrew Pinski <pinskia at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
Component|rtl-optimization |tree-optimization
--- Comment #2 from Andrew Pinski <pinskia at gcc dot gnu.org> ---
At the tree level we get:
_1 = REALPART_EXPR <i_5(D)>;
_2 = (unsigned int) _1;
_3 = IMAGPART_EXPR <i_5(D)>;
_4 = (unsigned int) _3;
_6 = COMPLEX_EXPR <_2, _4>;
But I suspect we could use VCE instead ...
> long f(long x){
> long y = x >> 32;
> y <<= 32;
> int z = x;
> return z | y;
> }
You have a sign extend in there. That is the top bit of z (or the 32nd bit of
x) could done for the top 32bits of the return. So this is not exactly the
same.
We do however optimize:
unsigned long f(unsigned long x){
long y = x >> 32;
y <<= 32;
unsigned z = x;
return z | y;
}
Now.
