tree: add build_string_literal overloads

Simplify several calls to build_string_literal by not requiring redundant
strlen or IDENTIFIER_* in the caller.

I also corrected a wrong comment on IDENTIFIER_LENGTH.

gcc/ChangeLog:

	* tree.h (build_string_literal): New one-argument overloads that
	take tree (identifier) and const char *.
	* builtins.cc (fold_builtin_FILE)
	(fold_builtin_FUNCTION)
	* gimplify.cc (gimple_add_init_for_auto_var)
	* vtable-verify.cc (verify_bb_vtables): Simplify calls.

gcc/cp/ChangeLog:

	* cp-gimplify.cc (fold_builtin_source_location)
	* vtable-class-hierarchy.cc (register_all_pairs): Simplify calls to
	build_string_literal.
	(build_string_from_id): Remove.

2 files changed, 6 insertions, 20 deletions

diff --git a/gcc/cp/cp-gimplify.cc b/gcc/cp/cp-gimplify.cc
index 28c3398..cc8bfad 100644
--- a/gcc/cp/cp-gimplify.cc
+++ b/gcc/cp/cp-gimplify.cc
@@ -3378,10 +3378,10 @@ fold_builtin_source_location (location_t loc)
 	      if (const char *fname = LOCATION_FILE (loc))
 		{
 		  fname = remap_macro_filename (fname);
-		  val = build_string_literal (strlen (fname) + 1, fname);
+		  val = build_string_literal (fname);
 		}
 	      else
-		val = build_string_literal (1, "");
+		val = build_string_literal ("");
 	    }
 	  else if (strcmp (n, "_M_function_name") == 0)
 	    {
@@ -3390,7 +3390,7 @@ fold_builtin_source_location (location_t loc)
 	      if (current_function_decl)
 		name = cxx_printable_name (current_function_decl, 2);
 
-	      val = build_string_literal (strlen (name) + 1, name);
+	      val = build_string_literal (name);
 	    }
 	  else if (strcmp (n, "_M_line") == 0)
 	    val = build_int_cst (TREE_TYPE (field), LOCATION_LINE (loc));
diff --git a/gcc/cp/vtable-class-hierarchy.cc b/gcc/cp/vtable-class-hierarchy.cc
index cc1df1e..1e180ea 100644
--- a/gcc/cp/vtable-class-hierarchy.cc
+++ b/gcc/cp/vtable-class-hierarchy.cc
@@ -467,19 +467,6 @@ check_and_record_registered_pairs (tree vtable_decl, tree vptr_address,
   return !inserted_something;
 }
 
-/* Given an IDENTIFIER_NODE, build and return a string literal based on it.  */
-
-static tree
-build_string_from_id (tree identifier)
-{
-  int len;
-
-  gcc_assert (TREE_CODE (identifier) == IDENTIFIER_NODE);
-
-  len = IDENTIFIER_LENGTH (identifier);
-  return build_string_literal (len + 1, IDENTIFIER_POINTER (identifier));
-}
-
 /* A class may contain secondary vtables in it, for various reasons.
    This function goes through the decl chain of a class record looking
    for any fields that point to secondary vtables, and adding calls to
@@ -920,7 +907,7 @@ register_all_pairs (tree body)
 
 
       if (flag_vtv_debug)
-        str1 = build_string_from_id (DECL_NAME (base_ptr_var_decl));
+	str1 = build_string_literal (DECL_NAME (base_ptr_var_decl));
 
       new_type = build_pointer_type (TREE_TYPE (base_ptr_var_decl));
       arg1 = build1 (ADDR_EXPR, new_type, base_ptr_var_decl);
@@ -953,7 +940,7 @@ register_all_pairs (tree body)
                 if (vtable_decl)
                   {
                     vtable_should_be_output = TREE_ASM_WRITTEN (vtable_decl);
-                    str2 = build_string_from_id (DECL_NAME (vtable_decl));
+		    str2 = build_string_literal (DECL_NAME (vtable_decl));
                   }
 
                 if (vtable_decl && vtable_should_be_output)
@@ -1009,8 +996,7 @@ register_all_pairs (tree body)
       arg2 = build_key_buffer_arg (base_ptr_var_decl);
 
       if (str2 == NULL_TREE)
-        str2 = build_string_literal (strlen ("unknown") + 1,
-                                     "unknown");
+	str2 = build_string_literal ("unknown");
 
       if (flag_vtv_debug)
         output_set_info (current->class_info->class_type,