Adjust by-value function vec arguments to by-reference.

gcc/c/ChangeLog:

	* c-parser.c (c_parser_declaration_or_fndef): Adjust by-value function
	vec arguments to by-reference.
	(c_finish_omp_declare_simd): Same.
	(c_parser_compound_statement_nostart): Same.
	(c_parser_for_statement): Same.
	(c_parser_objc_methodprotolist): Same.
	(c_parser_oacc_routine): Same.
	(c_parser_omp_for_loop): Same.
	(c_parser_omp_declare_simd): Same.

gcc/ChangeLog:

	* dominance.c (prune_bbs_to_update_dominators): Adjust by-value vec
	arguments to by-reference.
	(iterate_fix_dominators): Same.
	* dominance.h (iterate_fix_dominators): Same.
	* ipa-prop.h: Call auto_vec::to_vec_legacy.
	* tree-data-ref.c (dump_data_dependence_relation): Adjust by-value vec
	arguments to by-reference.
	(debug_data_dependence_relation): Same.
	(dump_data_dependence_relations): Same.
	* tree-data-ref.h (debug_data_dependence_relation): Same.
	(dump_data_dependence_relations): Same.
	* tree-predcom.c (dump_chains): Same.
	(initialize_root_vars_lm): Same.
	(determine_unroll_factor): Same.
	(replace_phis_by_defined_names): Same.
	(insert_init_seqs): Same.
	(pcom_worker::tree_predictive_commoning_loop): Call
	 auto_vec::to_vec_legacy.
	* tree-ssa-pre.c (insert_into_preds_of_block): Adjust by-value vec
	arguments to by-reference.
	* tree-ssa-threadbackward.c (populate_worklist): Same.
	(back_threader::resolve_def): Same.
	* tree-vect-data-refs.c (vect_check_nonzero_value): Same.
	(vect_enhance_data_refs_alignment): Same.
	(vect_check_lower_bound): Same.
	(vect_prune_runtime_alias_test_list): Same.
	(vect_permute_store_chain): Same.
	* tree-vect-slp-patterns.c (vect_normalize_conj_loc): Same.
	* tree-vect-stmts.c (vect_create_vectorized_demotion_stmts): Same.
	* tree-vectorizer.h (vect_permute_store_chain): Same.
	* vec.c (test_init): New function.
	(vec_c_tests): Call new function.
	* vec.h (vec): Declare ctors, dtor, and assignment.
	(auto_vec::vec_to_legacy): New function.
	(vec::copy): Adjust initialization.

1 files changed, 37 insertions, 10 deletions

diff --git a/gcc/vec.c b/gcc/vec.c
index f9dbb2c..6d767cc 100644
--- a/gcc/vec.c
+++ b/gcc/vec.c
@@ -38,16 +38,6 @@ along with GCC; see the file COPYING3.  If not see
 #include "diagnostic-core.h"
 #endif
 
-/* vNULL is an empty type with a template cast operation that returns
-   a zero-initialized vec<T, A, L> instance.  Use this when you want
-   to assign nil values to new vec instances or pass a nil vector as
-   a function call argument.
-
-   We use this technique because vec<T, A, L> must be PODs (they are
-   stored in unions and passed in vararg functions), this means that
-   they cannot have ctors/dtors.  */
-vnull vNULL;
-
 /* Vector memory usage.  */
 class vec_usage: public mem_usage
 {
@@ -282,6 +272,42 @@ safe_push_range (vec <int>&v, int start, int limit)
     v.safe_push (i);
 }
 
+/* Verify forms of initialization.  */
+
+static void
+test_init ()
+{
+  {
+    vec<int> v1{ };
+    ASSERT_EQ (0, v1.length ());
+
+    vec<int> v2 (v1);
+    ASSERT_EQ (0, v2.length ());
+  }
+
+  {
+    vec<int> v1 = vec<int>();
+    ASSERT_EQ (0, v1.length ());
+
+    vec<int> v2 = v1;
+    ASSERT_EQ (0, v2.length ());
+  }
+
+  {
+    vec<int> v1 (vNULL);
+    ASSERT_EQ (0, v1.length ());
+    v1.safe_push (1);
+
+    vec<int> v2 (v1);
+    ASSERT_EQ (1, v1.length ());
+    v2.safe_push (1);
+
+    ASSERT_EQ (2, v1.length ());
+    ASSERT_EQ (2, v2.length ());
+    v1.release ();
+  }
+}
+
 /* Verify that vec::quick_push works correctly.  */
 
 static void
@@ -547,6 +573,7 @@ test_auto_delete_vec ()
 void
 vec_c_tests ()
 {
+  test_init ();
   test_quick_push ();
   test_safe_push ();
   test_truncate ();