https://gcc.gnu.org/bugzilla/show_bug.cgi?id=103903
Bug ID: 103903
Summary: Loops handling r,g,b values are not vectorized to use
power of 2 vectors even if they can
Product: gcc
Version: 12.0
Status: UNCONFIRMED
Severity: enhancement
Priority: P3
Component: middle-end
Assignee: unassigned at gcc dot gnu.org
Reporter: hubicka at gcc dot gnu.org
Target Milestone: ---
This is another textcase comming from Firefox's LightPixel. I am not sure if
this is duplicate, but I think it is quite common in programs dealing with RGB
values.
To match the vectorized code we would need to move from SLP vectorizing the 3
parallel computations to vectorising the loop.
struct a {float r,g,b;};
struct a src[100000], dest[100000];
void
test ()
{
int i;
for (i=0;i<100000;i++)
{
dest[i].r/=src[i].g;
dest[i].g/=src[i].g;
dest[i].b/=src[i].b;
}
}
is vectorized to do 3 operaitons at a time, while equivalent:
float src[300000], dest[300000];
void
test ()
{
int i;
for (i=0;i<300000;i++)
{
dest[i]/=src[i];
}
}
runs faster.
