[PR middle-end/71373] Document missing OMP_CLAUSE_* in gcc/tree-nested.c

	gcc/
	PR middle-end/71373
	* tree-nested.c (convert_nonlocal_omp_clauses)
	(convert_local_omp_clauses): Document missing OMP_CLAUSE_*.

From-SVN: r237386

gcc/ChangeLog

 2016-06-13  Thomas Schwinge  <thomas@codesourcery.com>
 
+	PR middle-end/71373
+	* tree-nested.c (convert_nonlocal_omp_clauses)
+	(convert_local_omp_clauses): Document missing OMP_CLAUSE_*.
+
 	* tree-cfg.c (edge_to_cases_cleanup): Fix CASE_CHAIN typo.
 	* tree.def (CASE_LABEL_EXPR): Likewise.
 

gcc/tree-nested.c

@@ -1203,17 +1203,29 @@ convert_nonlocal_omp_clauses (tree *pclauses, struct walk_stmt_info *wi)
 	case OMP_CLAUSE_AUTO:
 	  break;
 
+	  /* OpenACC tile clauses are discarded during gimplification.  */
 	case OMP_CLAUSE_TILE:
-	  /* OpenACC tile clauses are discarded during gimplification, so we
-	     don't expect to see anything here.  */
-	  gcc_unreachable ();
-
+	  /* The following clause belongs to the OpenACC cache directive, which
+	     is discarded during gimplification.  */
 	case OMP_CLAUSE__CACHE_:
-	  /* These clauses belong to the OpenACC cache directive, which is
-	     discarded during gimplification, so we don't expect to see
-	     anything here.  */
-	  gcc_unreachable ();
-
+	  /* The following clauses are only allowed in the OpenMP declare simd
+	     directive, so not seen here.  */
+	case OMP_CLAUSE_UNIFORM:
+	case OMP_CLAUSE_INBRANCH:
+	case OMP_CLAUSE_NOTINBRANCH:
+	  /* The following clauses are only allowed on OpenMP cancel and
+	     cancellation point directives, which at this point have already
+	     been lowered into a function call.  */
+	case OMP_CLAUSE_FOR:
+	case OMP_CLAUSE_PARALLEL:
+	case OMP_CLAUSE_SECTIONS:
+	case OMP_CLAUSE_TASKGROUP:
+	  /* The following clauses are only added during OMP lowering; nested
+	     function decomposition happens before that.  */
+	case OMP_CLAUSE__LOOPTEMP_:
+	case OMP_CLAUSE__SIMDUID_:
+	case OMP_CLAUSE__GRIDDIM_:
+	  /* Anything else.  */
 	default:
 	  gcc_unreachable ();
 	}
@@ -1899,17 +1911,29 @@ convert_local_omp_clauses (tree *pclauses, struct walk_stmt_info *wi)
 	case OMP_CLAUSE_AUTO:
 	  break;
 
+	  /* OpenACC tile clauses are discarded during gimplification.  */
 	case OMP_CLAUSE_TILE:
-	  /* OpenACC tile clauses are discarded during gimplification, so we
-	     don't expect to see anything here.  */
-	  gcc_unreachable ();
-
+	  /* The following clause belongs to the OpenACC cache directive, which
+	     is discarded during gimplification.  */
 	case OMP_CLAUSE__CACHE_:
-	  /* These clauses belong to the OpenACC cache directive, which is
-	     discarded during gimplification, so we don't expect to see
-	     anything here.  */
-	  gcc_unreachable ();
-
+	  /* The following clauses are only allowed in the OpenMP declare simd
+	     directive, so not seen here.  */
+	case OMP_CLAUSE_UNIFORM:
+	case OMP_CLAUSE_INBRANCH:
+	case OMP_CLAUSE_NOTINBRANCH:
+	  /* The following clauses are only allowed on OpenMP cancel and
+	     cancellation point directives, which at this point have already
+	     been lowered into a function call.  */
+	case OMP_CLAUSE_FOR:
+	case OMP_CLAUSE_PARALLEL:
+	case OMP_CLAUSE_SECTIONS:
+	case OMP_CLAUSE_TASKGROUP:
+	  /* The following clauses are only added during OMP lowering; nested
+	     function decomposition happens before that.  */
+	case OMP_CLAUSE__LOOPTEMP_:
+	case OMP_CLAUSE__SIMDUID_:
+	case OMP_CLAUSE__GRIDDIM_:
+	  /* Anything else.  */
 	default:
 	  gcc_unreachable ();
 	}