builtins.def (BUILT_IN_VA_ARG_PACK): New built-in.

	* builtins.def (BUILT_IN_VA_ARG_PACK): New built-in.
	* tree.h (CALL_EXPR_VA_ARG_PACK): Define.
	* tree-inline.h (copy_body_data): Add call_expr field.
	* tree-inline.c (expand_call_inline): Initialize call_expr.
	(copy_bb): Append anonymous inline fn arguments to arguments
	when inlining a CALL_EXPR_VA_ARG_PACK call.
	* builtins.c (expand_builtin): Issue an error if
	BUILT_IN_VA_ARG_PACK is seen during expand.
	(fold_call_expr, fold_builtin_call_array): Don't fold
	CALL_EXPR_VA_ARG_PACK CALL_EXPRs or calls with
	__builtin_va_arg_pack () call as last argument.
	* gimplify.c (gimplify_call_expr): If last argument to a vararg
	function is __builtin_va_arg_pack (), decrease number of call
	arguments and instead set CALL_EXPR_VA_ARG_PACK on the CALL_EXPR.
	* expr.c (expand_expr_real_1): Issue an error if
	CALL_EXPR_VA_ARG_PACK CALL_EXPR is seen during expand.
	* tree-pretty-print.c (dump_generic_node): Handle printing
	CALL_EXPR_VA_ARG_PACK bit on CALL_EXPRs.
	* doc/extend.texi (__builtin_va_arg_pack): Document.

	* gcc.c-torture/execute/va-arg-pack-1.c: New test.
	* gcc.dg/va-arg-pack-1.c: New test.

From-SVN: r128150

1 files changed, 44 insertions, 2 deletions

diff --git a/gcc/gimplify.c b/gcc/gimplify.c
index 5c376ac..ee8ef09 100644
--- a/gcc/gimplify.c
+++ b/gcc/gimplify.c
@@ -2170,8 +2170,50 @@ gimplify_call_expr (tree *expr_p, tree *pre_p, bool want_value)
 	    }
 	}
     }
-  else if (nargs != 0)
-    CALL_CANNOT_INLINE_P (*expr_p) = 1;
+  else
+    {
+      if (nargs != 0)
+	CALL_CANNOT_INLINE_P (*expr_p) = 1;
+      i = 0;
+      p = NULL_TREE;
+    }
+
+  /* If the last argument is __builtin_va_arg_pack () and it is not
+     passed as a named argument, decrease the number of CALL_EXPR
+     arguments and set instead the CALL_EXPR_VA_ARG_PACK flag.  */
+  if (!p
+      && i < nargs
+      && TREE_CODE (CALL_EXPR_ARG (*expr_p, nargs - 1)) == CALL_EXPR)
+    {
+      tree last_arg = CALL_EXPR_ARG (*expr_p, nargs - 1);
+      tree last_arg_fndecl = get_callee_fndecl (last_arg);
+
+      if (last_arg_fndecl
+	  && TREE_CODE (last_arg_fndecl) == FUNCTION_DECL
+	  && DECL_BUILT_IN_CLASS (last_arg_fndecl) == BUILT_IN_NORMAL
+	  && DECL_FUNCTION_CODE (last_arg_fndecl) == BUILT_IN_VA_ARG_PACK)
+	{
+	  tree call = *expr_p;
+
+	  --nargs;
+	  *expr_p = build_call_array (TREE_TYPE (call), CALL_EXPR_FN (call),
+				      nargs, CALL_EXPR_ARGP (call));
+	  /* Copy all CALL_EXPR flags, locus and block, except
+	     CALL_EXPR_VA_ARG_PACK flag.  */
+	  CALL_EXPR_STATIC_CHAIN (*expr_p) = CALL_EXPR_STATIC_CHAIN (call);
+	  CALL_EXPR_TAILCALL (*expr_p) = CALL_EXPR_TAILCALL (call);
+	  CALL_EXPR_RETURN_SLOT_OPT (*expr_p)
+	    = CALL_EXPR_RETURN_SLOT_OPT (call);
+	  CALL_FROM_THUNK_P (*expr_p) = CALL_FROM_THUNK_P (call);
+	  CALL_CANNOT_INLINE_P (*expr_p)
+	    = CALL_CANNOT_INLINE_P (call);
+	  TREE_NOTHROW (*expr_p) = TREE_NOTHROW (call);
+	  SET_EXPR_LOCUS (*expr_p, EXPR_LOCUS (call));
+	  TREE_BLOCK (*expr_p) = TREE_BLOCK (call);
+	  /* Set CALL_EXPR_VA_ARG_PACK.  */
+	  CALL_EXPR_VA_ARG_PACK (*expr_p) = 1;
+	}
+    }
 
   /* Finally, gimplify the function arguments.  */
   for (i = (PUSH_ARGS_REVERSED ? nargs - 1 : 0);