C++ ABI change: destroy value arguments in caller.

* calls.c (initialize_argument_information): Pass the address of
        the TARGET_EXPR temporary rather than storing it into another.
        * semantics.c (genrtl_start_function, genrtl_finish_function): Don't
        create an extra binding level for the parameters.
        * decl.c (store_parm_decls): Don't do parameter cleanups.

From-SVN: r48154

gcc/ChangeLog

@@ -1,3 +1,9 @@
+2001-12-18  Jason Merrill  <jason@redhat.com>
+
+	C++ ABI change: destroy value arguments in caller.
+	* calls.c (initialize_argument_information): Pass the address of
+	the TARGET_EXPR temporary rather than storing it into another.
+
 Tue Dec 18 07:09:06 2001  Douglas B. Rupp  <rupp@gnat.com>
 
 	* config/alpha/xm-vms.h (INCLUDE_DEFAULTS): Add /gnu/include.

gcc/calls.c

@@ -1212,6 +1212,16 @@ initialize_argument_information (num_actuals, args, args_size, n_named_args,
 					   args[i].tree_value);
 	      type = build_pointer_type (type);
 	    }
+	  else if (TREE_CODE (args[i].tree_value) == TARGET_EXPR)
+	    {
+	      /* In the V3 C++ ABI, parameters are destroyed in the caller.
+		 We implement this by passing the address of the temporary
+	         rather than expanding it into another allocated slot.  */
+	      args[i].tree_value = build1 (ADDR_EXPR,
+					   build_pointer_type (type),
+					   args[i].tree_value);
+	      type = build_pointer_type (type);
+	    }
 	  else
 	    {
 	      /* We make a copy of the object and pass the address to the

gcc/cp/ChangeLog

@@ -1,3 +1,10 @@
+2001-12-18  Jason Merrill  <jason@redhat.com>
+
+	C++ ABI change: destroy value arguments in caller.
+	* semantics.c (genrtl_start_function, genrtl_finish_function): Don't
+	create an extra binding level for the parameters.
+	* decl.c (store_parm_decls): Don't do parameter cleanups.
+
 2001-12-18  Nathan Sidwell  <nathan@codesourcery.com>
 
 	* call.c (build_new_method_call): Use '%#V'.

gcc/cp/NEWS

@@ -40,6 +40,10 @@
   forms of `operator delete[]', and declared the two-argument form
   before the one-argument form.
 
+* The C++ ABI has been changed so that when a parameter is passed by value,
+  any cleanup for that parameter is performed in the caller, as specified
+  by the ia64 C++ ABI, rather than the called function as before.
+
 *** Changes in GCC 3.0:
 
 * Support for guiding declarations has been removed.

gcc/cp/decl.c

@@ -13790,7 +13790,6 @@ store_parm_decls (current_function_parms)
 {
   register tree fndecl = current_function_decl;
   register tree parm;
-  tree cleanups = NULL_TREE;
 
   /* This is a chain of any other decls that came in among the parm
      declarations.  If a parm is declared with  enum {foo, bar} x;
@@ -13821,20 +13820,11 @@ store_parm_decls (current_function_parms)
 	  next = TREE_CHAIN (parm);
 	  if (TREE_CODE (parm) == PARM_DECL)
 	    {
-	      tree cleanup;
-
 	      if (DECL_NAME (parm) == NULL_TREE
 		  || TREE_CODE (parm) != VOID_TYPE)
 		pushdecl (parm);
 	      else
 		error ("parameter `%D' declared void", parm);
-
-	      cleanup = (processing_template_decl
-			 ? NULL_TREE
-			 : maybe_build_cleanup (parm));
-
-	      if (cleanup)
-		cleanups = tree_cons (parm, cleanup, cleanups);
 	    }
 	  else
 	    {
@@ -13860,16 +13850,6 @@ store_parm_decls (current_function_parms)
      DECL_ARGUMENTS is not modified.  */
   storedecls (chainon (nonparms, DECL_ARGUMENTS (fndecl)));
 
-  /* Now that we have initialized the parms, we can start their
-     cleanups.  We cannot do this before, since expand_decl_cleanup
-     should not be called before the parm can be used.  */
-  while (cleanups)
-    {
-      finish_decl_cleanup (TREE_PURPOSE (cleanups),
-			   TREE_VALUE (cleanups));
-      cleanups = TREE_CHAIN (cleanups);
-    }
-
   /* Do the starting of the exception specifications, if we have any.  */
   if (flag_exceptions && !processing_template_decl
       && flag_enforce_eh_specs

gcc/cp/semantics.c

@@ -2610,7 +2610,6 @@ genrtl_start_function (fn)
   ++function_depth;
 
   /* Create a binding level for the parameters.  */
-  expand_start_bindings (2);
   expand_function_start (fn, /*parms_have_cleanups=*/0);
   /* If this function is `main'.  */
   if (DECL_MAIN_P (fn))
@@ -2667,7 +2666,7 @@ genrtl_finish_function (fn)
   immediate_size_expand = 1;
 
   /* Generate rtl for function exit.  */
-  expand_function_end (input_filename, lineno, 1);
+  expand_function_end (input_filename, lineno, 0);
 
   /* If this is a nested function (like a template instantiation that
      we're compiling in the midst of compiling something else), push a