middle-end: Exclude TOP permute from blend considerations

Similarly to UNKNOWN permutes, TOP needs to be excluded from being considered
for blends because it produces no permute to check.

gcc/ChangeLog:

	PR middle-end/98264
	* tree-vect-slp-patterns.c (linear_loads_p): Exclude TOP permute.

gcc/testsuite/ChangeLog:

	PR middle-end/98264
	* gcc.target/i386/pr98264.c: New test.
This commit is contained in:
Tamar Christina 2020-12-14 15:20:05 +00:00
parent 470a25b638
commit 159b0bd9ce
2 changed files with 24 additions and 1 deletions

View File

@ -0,0 +1,22 @@
/* { dg-do compile } */
/* { dg-additional-options "-O3 -w" } */
a[], g[], h[];
double b, c;
double j[];
i;
l() {
int e = 0;
for (; e < 80; e += 4) {
a[0] = h[e];
a[1] = h[e + 1];
j[0] = a[0] - c;
j[1] = a[1] + b;
__attribute__(()) k = *(double *)a, e, f = e = 0;
*g = k;
double *d = j;
for (; e < 2; e++)
if (d[e])
i = f;
}
}

View File

@ -240,7 +240,8 @@ linear_loads_p (slp_tree_to_load_perm_map_t *perm_cache, slp_tree root)
{
complex_load_perm_t res = linear_loads_p (perm_cache, child);
kind = vect_merge_perms (kind, res.first);
if (kind == PERM_UNKNOWN)
/* Unknown and Top are not valid on blends as they produce no permute. */
if (kind == PERM_UNKNOWN || kind == PERM_TOP)
return retval;
all_loads.safe_push (res.second);
}