diff options
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/testsuite/gcc.dg/vect/bb-slp-layout-20.c | 33 | ||||
| -rw-r--r-- | gcc/tree-vect-slp.cc | 40 |
2 files changed, 63 insertions, 10 deletions
diff --git a/gcc/testsuite/gcc.dg/vect/bb-slp-layout-20.c b/gcc/testsuite/gcc.dg/vect/bb-slp-layout-20.c new file mode 100644 index 0000000..ed7816b --- /dev/null +++ b/gcc/testsuite/gcc.dg/vect/bb-slp-layout-20.c @@ -0,0 +1,33 @@ +/* { dg-do compile } */ +/* { dg-additional-options "-fno-tree-loop-vectorize" } */ + +extern int a[][4], b[][4], c[][4], d[4], e[4]; +void f() +{ + int t0 = a[0][3]; + int t1 = a[1][3]; + int t2 = a[2][3]; + int t3 = a[3][3]; + int a0 = 0, a1 = 0, a2 = 0, a3 = 0, b0 = 0, b1 = 0, b2 = 0, b3 = 0; + for (int i = 0; i < 400; i += 4) + { + a0 += b[i][3] * t0; + a1 += b[i][2] * t1; + a2 += b[i][1] * t2; + a3 += b[i][0] * t3; + b0 += c[i][3] * t0; + b1 += c[i][2] * t1; + b2 += c[i][1] * t2; + b3 += c[i][0] * t3; + } + d[0] = a0; + d[1] = a1; + d[2] = a2; + d[3] = a3; + e[0] = b0; + e[1] = b1; + e[2] = b2; + e[3] = b3; +} + +/* { dg-final { scan-tree-dump-times "add new stmt: \[^\\n\\r\]* = VEC_PERM_EXPR" 3 "slp1" { target { vect_int_mult && vect_perm } } } } */ diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc index 59ec66a..b10f69d 100644 --- a/gcc/tree-vect-slp.cc +++ b/gcc/tree-vect-slp.cc @@ -4436,18 +4436,19 @@ change_vec_perm_layout (slp_tree node, lane_permutation_t &perm, IN_LAYOUT_I has no meaning for other types of node. - Keeping the node as-is is always valid. If the target doesn't appear to - support the node as-is then layout 0 has a high and arbitrary cost instead - of being invalid. On the one hand, this ensures that every node has at - least one valid layout, avoiding what would otherwise be an awkward - special case. On the other, it still encourages the pass to change - an invalid pre-existing layout choice into a valid one. */ + Keeping the node as-is is always valid. If the target doesn't appear + to support the node as-is, but might realistically support other layouts, + then layout 0 instead has the cost of a worst-case permutation. On the + one hand, this ensures that every node has at least one valid layout, + avoiding what would otherwise be an awkward special case. On the other, + it still encourages the pass to change an invalid pre-existing layout + choice into a valid one. */ int vect_optimize_slp_pass::internal_node_cost (slp_tree node, int in_layout_i, unsigned int out_layout_i) { - const int fallback_cost = 100; + const int fallback_cost = 1; if (SLP_TREE_CODE (node) == VEC_PERM_EXPR) { @@ -4457,8 +4458,9 @@ vect_optimize_slp_pass::internal_node_cost (slp_tree node, int in_layout_i, /* Check that the child nodes support the chosen layout. Checking the first child is enough, since any second child would have the same shape. */ + auto first_child = SLP_TREE_CHILDREN (node)[0]; if (in_layout_i > 0 - && !is_compatible_layout (SLP_TREE_CHILDREN (node)[0], in_layout_i)) + && !is_compatible_layout (first_child, in_layout_i)) return -1; change_vec_perm_layout (node, tmp_perm, in_layout_i, out_layout_i); @@ -4469,7 +4471,15 @@ vect_optimize_slp_pass::internal_node_cost (slp_tree node, int in_layout_i, if (count < 0) { if (in_layout_i == 0 && out_layout_i == 0) - return fallback_cost; + { + /* Use the fallback cost if the node could in principle support + some nonzero layout for both the inputs and the outputs. + Otherwise assume that the node will be rejected later + and rebuilt from scalars. */ + if (SLP_TREE_LANES (node) == SLP_TREE_LANES (first_child)) + return fallback_cost; + return 0; + } return -1; } @@ -4498,8 +4508,18 @@ vect_optimize_slp_pass::internal_node_cost (slp_tree node, int in_layout_i, if (!vect_transform_slp_perm_load_1 (m_vinfo, node, tmp_perm, vNULL, nullptr, vf, true, false, &n_perms)) { + auto rep = SLP_TREE_REPRESENTATIVE (node); if (out_layout_i == 0) - return fallback_cost; + { + /* Use the fallback cost if the load is an N-to-N permutation. + Otherwise assume that the node will be rejected later + and rebuilt from scalars. */ + if (STMT_VINFO_GROUPED_ACCESS (rep) + && (DR_GROUP_SIZE (DR_GROUP_FIRST_ELEMENT (rep)) + == SLP_TREE_LANES (node))) + return fallback_cost; + return 0; + } return -1; } |