Created a new function, gimple_build_vector_from_elems,
for use when creating vectorized definitions for basic block
vectorization in vect_create_constant_vectors.
The existing gimple_build_vector function cannot be used
for SVE vector types because it relies on the type
associated with the tree_vector_builder having a constant
number of subparts. Even if that limitation were lifted, the
possibility of tree_vector_builder patterns being used is
inappropriate.
The new function takes a vector type and vec of tree nodes
giving the element values to put into the built vector, instead of an
instance of tree_vector_builder. If the number of values is zero then
a zero constant is built. If all values are constant then a vector
constant is built. Otherwise, a new constructor node is created.
gcc/ChangeLog:
* gimple-fold.cc (gimple_build_vector_from_elems): Define a
new function to build a vector from a list of elements that need
not be complete.
* gimple-fold.h (gimple_build_vector_from_elems): Declare a new
function and a simpler overloaded version with fewer parameters.
* tree-vect-slp.cc (vect_create_constant_vectors):
For basic block SLP vectorization, pad each constant to the
minimum vector length (which is the same as the actual vector
length, except in the case of variable-length vector types).
Use gimple_build_vector_from_elems instead of
duplicate_and_interleave to create non-uniform constant
vectors for BB SLP vectorization.
---
gcc/gimple-fold.cc | 54 ++++++++++++++++++++++++++++++++++++++++++++
gcc/gimple-fold.h | 14 ++++++++++++
gcc/tree-vect-slp.cc | 42 +++++++++++++++++++++++++++-------
3 files changed, 102 insertions(+), 8 deletions(-)
diff --git a/gcc/gimple-fold.cc b/gcc/gimple-fold.cc
index 3fc76313622..d7a16569f5a 100644
--- a/gcc/gimple-fold.cc
+++ b/gcc/gimple-fold.cc
@@ -11274,6 +11274,60 @@ gimple_build_vector (gimple_stmt_iterator *gsi,
return builder->build ();
}
+/* Build a vector of type VECTYPE from a partial list of ELTS, handling the
case
+ in which some elements are non-constant, and padding the tail with zeros
+ if the list of values may be shorter than the number of subparts implied by
+ VECTYPE (including when the vector type is variable-length).
+
+ Return a gimple value for the result, inserting any new instructions
+ to GSI honoring BEFORE and UPDATE. */
+
+tree
+gimple_build_vector_from_elems (gimple_stmt_iterator *gsi, bool before,
+ gsi_iterator_update update, location_t loc,
+ tree vectype, const vec<tree> &elts)
+{
+ unsigned int encoded_nelts = elts.length ();
+ gimple_seq seq = NULL;
+ gcc_assert (TREE_CODE (vectype) == VECTOR_TYPE);
+ unsigned int lower_bound
+ = constant_lower_bound (TYPE_VECTOR_SUBPARTS (vectype));
+ gcc_assert (encoded_nelts <= lower_bound);
+
+ if (encoded_nelts == 0)
+ return build_zero_cst (vectype);
+
+ /* Prepare a vector of constructor elements and find out whether all
+ of the element values are constant. */
+ vec<constructor_elt, va_gc> *v;
+ vec_alloc (v, encoded_nelts);
+ bool is_constant = true;
+
+ for (unsigned int i = 0; i < encoded_nelts; ++i)
+ {
+ if (!CONSTANT_CLASS_P (elts[i]))
+ is_constant = false;
+
+ CONSTRUCTOR_APPEND_ELT (v, NULL_TREE, elts[i]);
+ }
+
+ /* If all element values are constant then we can return a new VECTOR_CST
+ node. Any elements for which no value is supplied will be zero. */
+ if (is_constant)
+ return build_vector_from_ctor (vectype, v);
+
+ tree res;
+ if (gimple_in_ssa_p (cfun))
+ res = make_ssa_name (vectype);
+ else
+ res = create_tmp_reg (vectype);
+ gimple *stmt = gimple_build_assign (res, build_constructor (vectype, v));
+ gimple_set_location (stmt, loc);
+ gimple_seq_add_stmt_without_update (&seq, stmt);
+ gimple_build_insert_seq (gsi, before, update, seq);
+ return res;
+}
+
/* Emit gimple statements into &stmts that take a value given in OLD_SIZE
and generate a value guaranteed to be rounded upwards to ALIGN.
diff --git a/gcc/gimple-fold.h b/gcc/gimple-fold.h
index 7244941722d..358c269aacc 100644
--- a/gcc/gimple-fold.h
+++ b/gcc/gimple-fold.h
@@ -243,6 +243,20 @@ gimple_build_vector (gimple_seq *seq, tree_vector_builder
*builder)
UNKNOWN_LOCATION, builder);
}
+extern tree gimple_build_vector_from_elems (gimple_stmt_iterator *, bool,
+ enum gsi_iterator_update,
+ location_t, tree vectype,
+ const vec<tree> &);
+
+inline tree
+gimple_build_vector_from_elems (gimple_seq *seq, tree vectype,
+ const vec<tree> &elts)
+{
+ gimple_stmt_iterator gsi = gsi_last (*seq);
+ return gimple_build_vector_from_elems (&gsi, false, GSI_CONTINUE_LINKING,
+ UNKNOWN_LOCATION, vectype, elts);
+}
+
extern tree gimple_build_round_up (gimple_stmt_iterator *, bool,
enum gsi_iterator_update,
location_t, tree, tree,
diff --git a/gcc/tree-vect-slp.cc b/gcc/tree-vect-slp.cc
index 1d62331a922..a7c18d5e4c1 100644
--- a/gcc/tree-vect-slp.cc
+++ b/gcc/tree-vect-slp.cc
@@ -10836,7 +10836,7 @@ vect_create_constant_vectors (vec_info *vinfo, slp_tree
op_node)
unsigned j, number_of_places_left_in_vector;
tree vector_type;
tree vop;
- int group_size = op_node->ops.length ();
+ unsigned int group_size = op_node->ops.length ();
unsigned int vec_num, i;
unsigned number_of_copies = 1;
bool constant_p;
@@ -10866,12 +10866,27 @@ vect_create_constant_vectors (vec_info *vinfo,
slp_tree op_node)
(s1, s2, ..., s8). We will create two vectors {s1, s2, s3, s4} and
{s5, s6, s7, s8}. */
- /* When using duplicate_and_interleave, we just need one element for
- each scalar statement. */
- if (!TYPE_VECTOR_SUBPARTS (vector_type).is_constant (&nunits))
- nunits = group_size;
+ unsigned int elt_count = group_size;
+ if (is_a<bb_vec_info> (vinfo))
+ {
+ /* We don't use duplicate_and_interleave for basic block vectorization.
+ We know that either the group size is exactly divisible by the vector
+ length or it fits within a single vector, so all we need to do for
+ VLA is to pad the constant to the minimum vector length. */
+ nunits = constant_lower_bound (TYPE_VECTOR_SUBPARTS (vector_type));
+ gcc_checking_assert (multiple_p (group_size, nunits)
+ || known_le (group_size, nunits));
+ elt_count = MAX (nunits, group_size);
+ }
+ else
+ {
+ /* When using duplicate_and_interleave, we just need one element for
+ each scalar statement. */
+ if (!TYPE_VECTOR_SUBPARTS (vector_type).is_constant (&nunits))
+ nunits = group_size;
+ }
- number_of_copies = nunits * number_of_vectors / group_size;
+ number_of_copies = nunits * number_of_vectors / elt_count;
number_of_places_left_in_vector = nunits;
constant_p = true;
@@ -10881,9 +10896,15 @@ vect_create_constant_vectors (vec_info *vinfo,
slp_tree op_node)
stmt_vec_info insert_after = NULL;
for (j = 0; j < number_of_copies; j++)
{
- tree op;
- for (i = group_size - 1; op_node->ops.iterate (i, &op); i--)
+ for (i = elt_count; i-- > 0;)
{
+ tree op;
+ if (i < group_size)
+ op = op_node->ops[i];
+ else
+ /* Pad with zeros. */
+ op = build_zero_cst (TREE_TYPE (vector_type));
+
/* Create 'vect_ = {op0,op1,...,opn}'. */
tree orig_op = op;
if (number_of_places_left_in_vector == nunits)
@@ -10969,6 +10990,11 @@ vect_create_constant_vectors (vec_info *vinfo,
slp_tree op_node)
? multiple_p (type_nunits, nunits)
: known_eq (type_nunits, nunits))
vec_cst = gimple_build_vector (&ctor_seq, &elts);
+ else if (is_a<bb_vec_info> (vinfo))
+ {
+ vec_cst = gimple_build_vector_from_elems (&ctor_seq,
+ elts.type (), elts);
+ }
else
{
if (permute_results.is_empty ())
--
2.43.0