[PATCH v14 06/19] vect: Handle bb_slp_info in check_load_store_for_partial_vectors

In preparation for enabling tail-predication for basic block SLP
vectorization, the function used to check whether a load or store
statement in a loop is possible using partial vectors needs to be
updated to work for BB SLP too.

This preparatory commit does not change any of the callers of
check_load_store_for_partial_vectors, therefore loop_vinfo is
expected to be non-null within the modified function (for now).

gcc/ChangeLog:

	* tree-vect-stmts.cc (check_load_store_for_partial_vectors):
	Change parameter type from loop_vec_info to vec_info *.  Use
	dyn_cast to get a loop_vec_info or null.  Return false if doing
	BB SLP and SLP_TREE_LANES might exceed the number of subparts in
	the passed-in vector type.  Pass vec_info * instead of
	loop_vec_info to vect_get_num_copies, vect_record_len and
	vect_record_mask.  Pass the SLP node through to vect_record_len
	and vect_record_mask to let them get SLP_TREE_LANES.
	When calculating the number of vectors, get the group size from
	SLP_TREE_LANES instead of a parameter (e.g., DR_GROUP_SIZE) if
	doing BB SLP vectorization.
---
 gcc/tree-vect-stmts.cc | 44 +++++++++++++++++++++++++-----------------
 1 file changed, 26 insertions(+), 18 deletions(-)

diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc
index 978fb288089..b033a58d507 100644
--- a/gcc/tree-vect-stmts.cc
+++ b/gcc/tree-vect-stmts.cc
@@ -1443,10 +1443,10 @@ vect_get_load_store_partial_vector_style (tree vectype, bool is_load,
   return vect_load_store_partial_vectors_none;
 }
 
-/* Check whether a load or store statement in the loop described by
-   LOOP_VINFO is possible in a loop using partial vectors.  This is
-   testing whether the vectorizer pass has the appropriate support,
-   as well as whether the target does.
+/* Check whether a load or store statement in the loop or SLP region described
+   by VINFO is possible using partial vectors.  This is testing whether the
+   vectorizer pass has the appropriate support, as well as whether the target
+   does.
 
    VLS_TYPE says whether the statement is a load or store and VECTYPE
    is the type of the vector being loaded or stored.  SLP_NODE is the SLP
@@ -1457,14 +1457,14 @@ vect_get_load_store_partial_vector_style (tree vectype, bool is_load,
    its arguments.  If the load or store is conditional, SCALAR_MASK is the
    condition under which it occurs.
 
-   Return false if a loop using partial vectors is not supported, otherwise
-   record the required rgroup control types.
+   Return false if a loop or SLP vectorization using partial vectors is not
+   supported, otherwise record the required rgroup control types.
 
    If partial vectors can be used and ELSVALS is nonzero the supported
    else values will be added to the vector ELSVALS points to.  */
 
 static bool
-check_load_store_for_partial_vectors (loop_vec_info loop_vinfo, tree vectype,
+check_load_store_for_partial_vectors (vec_info *vinfo, tree vectype,
 				      slp_tree slp_node,
 				      vec_load_store_type vls_type,
 				      unsigned int group_size,
@@ -1472,8 +1472,15 @@ check_load_store_for_partial_vectors (loop_vec_info loop_vinfo, tree vectype,
 				      slp_tree mask_node,
 				      vec<int> *elsvals = nullptr)
 {
+  loop_vec_info loop_vinfo = dyn_cast<loop_vec_info> (vinfo);
   vect_memory_access_type memory_access_type = ls->memory_access_type;
 
+  /* For SLP vectorization, we cannot use partial vectors if the
+     group could be wider than the vector type.  */
+  poly_uint64 nunits = TYPE_VECTOR_SUBPARTS (vectype);
+  if (!loop_vinfo && maybe_gt (SLP_TREE_LANES (slp_node), nunits))
+    return false;
+
   /* Invariant loads need no special support.  */
   if (memory_access_type == VMAT_INVARIANT)
     return true;
@@ -1495,7 +1502,7 @@ check_load_store_for_partial_vectors (loop_vec_info loop_vinfo, tree vectype,
 	  scalar_mask = def;
       }
 
-  unsigned int nvectors = vect_get_num_copies (loop_vinfo, slp_node);
+  unsigned int nvectors = vect_get_num_copies (vinfo, slp_node);
   machine_mode vecmode = TYPE_MODE (vectype);
   bool is_load = (vls_type == VLS_LOAD);
   if (memory_access_type == VMAT_LOAD_STORE_LANES)
@@ -1506,9 +1513,9 @@ check_load_store_for_partial_vectors (loop_vec_info loop_vinfo, tree vectype,
 						elsvals)
 		   : vect_store_lanes_supported (vectype, group_size, true));
       if (ifn == IFN_MASK_LEN_LOAD_LANES || ifn == IFN_MASK_LEN_STORE_LANES)
-	vect_record_len (loop_vinfo, nvectors, vectype, 1);
+	vect_record_len (vinfo, nvectors, vectype, 1, slp_node);
       else if (ifn == IFN_MASK_LOAD_LANES || ifn == IFN_MASK_STORE_LANES)
-	vect_record_mask (loop_vinfo, nvectors, vectype, scalar_mask);
+	vect_record_mask (vinfo, nvectors, vectype, scalar_mask, slp_node);
       else
 	{
 	  if (dump_enabled_p ())
@@ -1550,13 +1557,13 @@ check_load_store_for_partial_vectors (loop_vec_info loop_vinfo, tree vectype,
 						  memory_type,
 						  off_vectype, scale,
 						  elsvals))
-	vect_record_len (loop_vinfo, nvectors, vectype, 1);
+	vect_record_len (vinfo, nvectors, vectype, 1, slp_node);
       else if (internal_gather_scatter_fn_supported_p (ifn, vectype,
 						       memory_type,
 						       off_vectype, scale,
 						       elsvals)
 	       || memory_access_type == VMAT_GATHER_SCATTER_LEGACY)
-	vect_record_mask (loop_vinfo, nvectors, vectype, scalar_mask);
+	vect_record_mask (vinfo, nvectors, vectype, scalar_mask, slp_node);
       else
 	{
 	  if (dump_enabled_p ())
@@ -1600,8 +1607,9 @@ check_load_store_for_partial_vectors (loop_vec_info loop_vinfo, tree vectype,
     gcc_unreachable ();
   };
 
-  poly_uint64 nunits = TYPE_VECTOR_SUBPARTS (vectype);
-  poly_uint64 vf = LOOP_VINFO_VECT_FACTOR (loop_vinfo);
+  poly_uint64 size = loop_vinfo
+		       ? group_size * LOOP_VINFO_VECT_FACTOR (loop_vinfo)
+		       : SLP_TREE_LANES (slp_node);
   unsigned factor;
   vect_load_store_partial_vector_style partial_vector_style
     = vect_get_load_store_partial_vector_style (vectype, is_load, &factor,
@@ -1609,13 +1617,13 @@ check_load_store_for_partial_vectors (loop_vec_info loop_vinfo, tree vectype,
 
   if (partial_vector_style == vect_load_store_partial_vectors_len)
     {
-      nvectors = group_memory_nvectors (group_size * vf, nunits);
-      vect_record_len (loop_vinfo, nvectors, vectype, factor);
+      nvectors = group_memory_nvectors (size, nunits);
+      vect_record_len (vinfo, nvectors, vectype, factor, slp_node);
     }
   else if (partial_vector_style == vect_load_store_partial_vectors_mask)
     {
-      nvectors = group_memory_nvectors (group_size * vf, nunits);
-      vect_record_mask (loop_vinfo, nvectors, vectype, scalar_mask);
+      nvectors = group_memory_nvectors (size, nunits);
+      vect_record_mask (vinfo, nvectors, vectype, scalar_mask, slp_node);
     }
   else
     {
-- 
2.43.0