[rfa] atomic builtins for c++

[Richard Henderson <rth at redhat dot com>]

It appears that this is much simpler than I thought it would be.  All the
do-we-have-dependent-types-in-the-argument-list things are already taken
care of at the top of finish_call_expr.  And as finish_call_expr is what's
called during template expansion, by putting the call to
resolve_overloaded_builtin after the template handling in finish_call_expr
means don't have to worry about templates at all.

The only thing that's a teeny bit confusing is that is_overloaded_fn is true
for *all* FUNCTION_DECLs.  No way I'm touching that with a 100 foot pole.
Thus the somewhat curious placement of this bit of code.

Can you think of anything else I ought to be testing wrt templates?


r~


	* semantics.c (finish_call_expr): Call resolve_overloaded_builtin.

Index: cp/semantics.c
===================================================================
RCS file: /cvs/gcc/gcc/gcc/cp/semantics.c,v
retrieving revision 1.467
diff -u -p -d -r1.467 semantics.c
--- cp/semantics.c	9 Apr 2005 03:18:18 -0000	1.467
+++ cp/semantics.c	16 Apr 2005 00:26:28 -0000
@@ -1833,8 +1833,16 @@ finish_call_expr (tree fn, tree args, bo
 				       ? LOOKUP_NONVIRTUAL : 0));
     }
   else if (is_overloaded_fn (fn))
-    /* A call to a namespace-scope function.  */
-    result = build_new_function_call (fn, args);
+    {
+      /* If the function is an overloaded builtin, resolve it.  */
+      if (TREE_CODE (fn) == FUNCTION_DECL
+	  && DECL_BUILT_IN_CLASS (fn) == BUILT_IN_NORMAL)
+        result = resolve_overloaded_builtin (fn, args);
+
+      if (!result)
+	/* A call to a namespace-scope function.  */
+	result = build_new_function_call (fn, args);
+    }
   else if (TREE_CODE (fn) == PSEUDO_DTOR_EXPR)
     {
       if (args)
@@ -1851,6 +1859,7 @@ finish_call_expr (tree fn, tree args, bo
        have an overloaded `operator ()'.  */
     result = build_new_op (CALL_EXPR, LOOKUP_NORMAL, fn, args, NULL_TREE,
 			   /*overloaded_p=*/NULL);
+
   if (!result)
     /* A call where the function is unknown.  */
     result = build_function_call (fn, args);
Index: testsuite/g++.dg/ext/sync-1.C
===================================================================
RCS file: testsuite/g++.dg/ext/sync-1.C
diff -N testsuite/g++.dg/ext/sync-1.C
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ testsuite/g++.dg/ext/sync-1.C	16 Apr 2005 00:26:28 -0000
@@ -0,0 +1,40 @@
+// Validate that the __sync builtins are overloaded properly.
+// { dg-do compile }
+// { dg-options "-Werror" }
+
+#define TEST1(TYPE, BUILTIN)		\
+void t_##TYPE##BUILTIN(TYPE *p)		\
+{					\
+  __typeof(BUILTIN(p, 1)) *pp;		\
+  pp = p;				\
+}
+
+#define TEST2(BUILTIN)		\
+  TEST1(int, BUILTIN)		\
+  TEST1(long, BUILTIN)
+
+TEST2(__sync_fetch_and_add)
+TEST2(__sync_fetch_and_sub)
+TEST2(__sync_fetch_and_or)
+TEST2(__sync_fetch_and_and)
+TEST2(__sync_fetch_and_xor)
+TEST2(__sync_fetch_and_nand)
+
+TEST2(__sync_add_and_fetch)
+TEST2(__sync_sub_and_fetch)
+TEST2(__sync_or_and_fetch)
+TEST2(__sync_and_and_fetch)
+TEST2(__sync_xor_and_fetch)
+TEST2(__sync_nand_and_fetch)
+
+TEST2(__sync_lock_test_and_set)
+
+#define TEST3(TYPE)					\
+void t_##TYPE##__sync_val_compare_and_swap(TYPE *p)	\
+{							\
+  __typeof(__sync_val_compare_and_swap(p, 1, 2)) *pp;	\
+  pp = p;						\
+}
+
+TEST3(int)
+TEST3(long)
Index: testsuite/g++.dg/ext/sync-2.C
===================================================================
RCS file: testsuite/g++.dg/ext/sync-2.C
diff -N testsuite/g++.dg/ext/sync-2.C
--- /dev/null	1 Jan 1970 00:00:00 -0000
+++ testsuite/g++.dg/ext/sync-2.C	16 Apr 2005 00:26:28 -0000
@@ -0,0 +1,58 @@
+// Validate that the __sync builtins are overloaded properly in templates.
+// { dg-do compile }
+// { dg-options "-Werror" }
+
+
+#define TEST1(BUILTIN)			\
+template<typename T>			\
+void f##BUILTIN(T *p)			\
+{					\
+  __typeof(BUILTIN(p, 1)) *pp;		\
+  pp = p;				\
+}
+
+TEST1(__sync_fetch_and_add)
+TEST1(__sync_fetch_and_sub)
+TEST1(__sync_fetch_and_or)
+TEST1(__sync_fetch_and_and)
+TEST1(__sync_fetch_and_xor)
+TEST1(__sync_fetch_and_nand)
+
+TEST1(__sync_add_and_fetch)
+TEST1(__sync_sub_and_fetch)
+TEST1(__sync_or_and_fetch)
+TEST1(__sync_and_and_fetch)
+TEST1(__sync_xor_and_fetch)
+TEST1(__sync_nand_and_fetch)
+
+TEST1(__sync_lock_test_and_set)
+
+template<typename T>
+void f__sync_val_compare_and_swap(T *p)
+{
+  __typeof(__sync_val_compare_and_swap(p, 1, 2)) *pp;
+  pp = p;
+}
+
+#define TEST2(TYPE)			\
+void h_##TYPE ()			\
+{					\
+  TYPE x;				\
+  f__sync_fetch_and_add (&x);		\
+  f__sync_fetch_and_sub (&x);		\
+  f__sync_fetch_and_or (&x);		\
+  f__sync_fetch_and_and (&x);		\
+  f__sync_fetch_and_xor (&x);		\
+  f__sync_fetch_and_nand (&x);		\
+  f__sync_add_and_fetch (&x);		\
+  f__sync_sub_and_fetch (&x);		\
+  f__sync_or_and_fetch (&x);		\
+  f__sync_and_and_fetch (&x);		\
+  f__sync_xor_and_fetch (&x);		\
+  f__sync_nand_and_fetch (&x);		\
+  f__sync_lock_test_and_set (&x);	\
+  f__sync_val_compare_and_swap (&x);	\
+}
+
+TEST2(int)
+TEST2(long)