2020-12-12  Joern Rennecke  <joern.rennecke@embecosm.com>

	Fix match_dup bug of define_cond_exec.
	* gensupport.c (alter_predicate_for_insn): Handle MATCH_DUP.

diff --git a/gcc/gensupport.c b/gcc/gensupport.c
index e1ca06dbc1e..92275358078 100644
--- a/gcc/gensupport.c
+++ b/gcc/gensupport.c
@@ -1230,6 +1230,7 @@ alter_predicate_for_insn (rtx pattern, int alt, int max_op,
     case MATCH_OPERATOR:
     case MATCH_SCRATCH:
     case MATCH_PARALLEL:
+    case MATCH_DUP:
       XINT (pattern, 0) += max_op;
       break;