------- Comment #3 from irar at il dot ibm dot com 2008-09-14 10:04 -------
(In reply to comment #2)
> I don't follow. For vectorize2.c we have
>
> b[i] = lrint (a[i]);
>
> where we should be able to vectorize this using lrint vectorization and
> a scalar long -> int conversion (which is a no-op on i686 and should be
> vectorized on x86_64). There is no aliasing issue involved here.
I am working on x86_64 using -m32 (without -m32 I get
../../gcc.target/i386/vectorize2.c:15: note: function is not vectorizable.
../../gcc.target/i386/vectorize2.c:15: note: not vectorized: relevant stmt not
supported: D.1603_6 = lrint (D.1602_5); ).
I don't see any conversion:
foo ()
{
unsigned int ivtmp.65;
int pretmp.55;
double pretmp.54;
int i;
long int D.1579;
double D.1578;
<bb 2>:
<bb 3>:
# i_14 = PHI <i_7(4), 0(2)>
# ivtmp.65_13 = PHI <ivtmp.65_12(4), 256(2)>
D.1578_5 = a[i_14];
D.1579_6 = lrint (D.1578_5);
b[i_14] = D.1579_6;
i_7 = i_14 + 1;
ivtmp.65_12 = ivtmp.65_13 - 1;
if (ivtmp.65_12 != 0)
goto <bb 4>;
else
goto <bb 5>;
<bb 4>:
goto <bb 3>;
<bb 5>:
return;
}
The vectorized version (if the alias check is removed) is:
...
vector long int * ivtmp.120;
vector long int vect_var_.113;
...
vect_var_.111_20 = *ivtmp.110_18;
ivtmp.110_21 = ivtmp.110_18 + 16;
vect_var_.112_22 = *ivtmp.110_21;
vect_var_.113_23 = __builtin_ia32_vec_pack_sfix (vect_var_.111_20,
vect_var_.112_22);
*ivtmp.120_26 = vect_var_.113_23;
The alias check is for the store, checking *ivtmp.120_26 and b.
--
http://gcc.gnu.org/bugzilla/show_bug.cgi?id=37491
