This is a patch related to
https://gcc.gnu.org/pipermail/gcc-patches/2023-March/613977.html,
aiming for gcc14. Since the RISC-V target has vector modes (e.g. VNx1DImode)
with nelt smaller than 2, npat has to match with the nelt to create proper
vec_perm_indices.
I tested on x86_64-linux-gnu and didn't cause more failures, but wasn't sure if
total_elem would be used in the rest of the function. Should there be additional
changes in the vect_grouped_store_supported? Thank you!
gcc/ChangeLog:
Kevin Lee <kev...@rivosinc.com>
* tree-vect-data-refs.cc (vect_grouped_store_supported): Check
if the nelt is greater than one.
---
gcc/tree-vect-data-refs.cc | 13 ++++++++-----
1 file changed, 8 insertions(+), 5 deletions(-)
diff --git a/gcc/tree-vect-data-refs.cc b/gcc/tree-vect-data-refs.cc
index 8daf7bd7dd3..9c09cc973d0 100644
--- a/gcc/tree-vect-data-refs.cc
+++ b/gcc/tree-vect-data-refs.cc
@@ -5399,17 +5399,20 @@ vect_grouped_store_supported (tree vectype, unsigned
HOST_WIDE_INT count)
poly_uint64 nelt = GET_MODE_NUNITS (mode);
/* The encoding has 2 interleaved stepped patterns. */
- vec_perm_builder sel (nelt, 2, 3);
- sel.quick_grow (6);
+
+ unsigned int npat = known_gt(nelt, (unsigned int) 1) ? 2 : 1;
+ unsigned int total_elem = npat * 3;
+ vec_perm_builder sel (nelt, npat, 3);
+ sel.quick_grow (total_elem);
for (i = 0; i < 3; i++)
{
- sel[i * 2] = i;
- sel[i * 2 + 1] = i + nelt;
+ sel[i * npat] = i;
+ sel[i * npat + 1] = i + nelt;
}
vec_perm_indices indices (sel, 2, nelt);
if (can_vec_perm_const_p (mode, mode, indices))
{
- for (i = 0; i < 6; i++)
+ for (i = 0; i < total_elem; i++)
sel[i] += exact_div (nelt, 2);
indices.new_vector (sel, 2, nelt);
if (can_vec_perm_const_p (mode, mode, indices))
--
2.25.1
