[PATCH v3 4/9] S/390: Do not use signaling vector comparisons on z13

[Ilya Leoshkevich]

z13 supports only non-signaling vector comparisons.  This means we
cannot vectorize LT, LE, GT, GE and LTGT when compiling for z13.  Notify
middle-end about this using more restrictive operator predicate in
vcond<V_HW:mode><V_HW2:mode>.

gcc/ChangeLog:

2019-08-21  Ilya Leoshkevich  <i...@linux.ibm.com>

        PR target/77918
        * config/s390/vector.md (vcond_comparison_operator): New
        predicate.
        (vcond<V_HW:mode><V_HW2:mode>): Use vcond_comparison_operator.
---
 gcc/config/s390/vector.md | 22 +++++++++++++++++++++-
 1 file changed, 21 insertions(+), 1 deletion(-)

diff --git a/gcc/config/s390/vector.md b/gcc/config/s390/vector.md
index 0702e1de835..d7a266c5605 100644
--- a/gcc/config/s390/vector.md
+++ b/gcc/config/s390/vector.md
@@ -614,10 +614,30 @@
   operands[2] = GEN_INT (GET_MODE_NUNITS (<MODE>mode) - 1);
 })
 
+(define_predicate "vcond_comparison_operator"
+  (match_operand 0 "comparison_operator")
+{
+  if (!HONOR_NANS (GET_MODE (XEXP (op, 0)))
+      && !HONOR_NANS (GET_MODE (XEXP (op, 1))))
+    return true;
+  switch (GET_CODE (op))
+    {
+    case LE:
+    case LT:
+    case GE:
+    case GT:
+    case LTGT:
+      /* Signaling vector comparisons are supported only on z14+.  */
+      return TARGET_Z14;
+    default:
+      return true;
+    }
+})
+
 (define_expand "vcond<V_HW:mode><V_HW2:mode>"
   [(set (match_operand:V_HW 0 "register_operand" "")
        (if_then_else:V_HW
-        (match_operator 3 "comparison_operator"
+        (match_operator 3 "vcond_comparison_operator"
                         [(match_operand:V_HW2 4 "register_operand" "")
                          (match_operand:V_HW2 5 "nonmemory_operand" "")])
         (match_operand:V_HW 1 "nonmemory_operand" "")
-- 
2.21.0