[PATCH 11/13] vect: Disable use of partial vectors for uncounted loops

[Victor Do Nascimento]

Given the current reliance of masking on niters and the fact this is
undetermined for uncounted loops, we circumvent this limitation by
disabling the use of partial vectors when vectorizing loops with an
unkown upper bound.

gcc/ChangeLog:

        * tree-vect-loop.cc (vect_analyze_loop_2): Disable partial
        vector use for uncounted loops.
---
 gcc/tree-vect-loop.cc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/gcc/tree-vect-loop.cc b/gcc/tree-vect-loop.cc
index 35fa01548df..3cfb9761f80 100644
--- a/gcc/tree-vect-loop.cc
+++ b/gcc/tree-vect-loop.cc
@@ -2143,6 +2143,9 @@ vect_analyze_loop_2 (loop_vec_info loop_vinfo, bool 
&fatal,
     orig_loop_vinfo = loop_vinfo;
   gcc_assert (orig_loop_vinfo);
 
+  if (LOOP_VINFO_NITERS_UNCOUNTED_P (loop_vinfo))
+    LOOP_VINFO_CAN_USE_PARTIAL_VECTORS_P (loop_vinfo) = false;
+
   /* The first group of checks is independent of the vector size.  */
   fatal = true;
 
-- 
2.43.0