call.c (magic_varargs_p): Return 3 for __builtin_*_overflow_p.

	* call.c (magic_varargs_p): Return 3 for __builtin_*_overflow_p.
	(build_over_call): For magic == 3, do no conversion only on 3rd
	argument.

	* c-c++-common/torture/builtin-arith-overflow-p-19.c: Run for C++ too.
	* g++.dg/ext/builtin-arith-overflow-2.C: New test.

From-SVN: r237755

diff --git a/gcc/cp/ChangeLog b/gcc/cp/ChangeLog
index 9ef7d4ef9555c9a95be63303fb5aa5c70e1d5d49..78dd88f20b268b9793fb48e0483f454607fed867 100644 (file)
--- a/gcc/cp/ChangeLog
+++ b/gcc/cp/ChangeLog
@@ -1,3 +1,9 @@
+2016-06-24  Jakub Jelinek  <jakub@redhat.com>
+
+       * call.c (magic_varargs_p): Return 3 for __builtin_*_overflow_p.
+       (build_over_call): For magic == 3, do no conversion only on 3rd
+       argument.
+
 2016-06-23  Andi Kleen  <ak@linux.intel.com>
 
        * Make-lang.in: Add support for autofdo.

diff --git a/gcc/cp/call.c b/gcc/cp/call.c
index b739fa0905d1ffa7e4ec864d5acf0419e1ea8edf..d77092b1ef51311880e5b072efc582124a455ab9 100644 (file)
--- a/gcc/cp/call.c
+++ b/gcc/cp/call.c
@@ -7132,7 +7132,8 @@ convert_for_arg_passing (tree type, tree val, tsubst_flags_t complain)
    which just decay_conversion or no conversions at all should be done.
    This is true for some builtins which don't act like normal functions.
    Return 2 if no conversions at all should be done, 1 if just
-   decay_conversion.  */
+   decay_conversion.  Return 3 for special treatment of the 3rd argument
+   for __builtin_*_overflow_p.  */
 
 int
 magic_varargs_p (tree fn)
@@ -7149,6 +7150,11 @@ magic_varargs_p (tree fn)
       case BUILT_IN_VA_START:
        return 1;
 
+      case BUILT_IN_ADD_OVERFLOW_P:
+      case BUILT_IN_SUB_OVERFLOW_P:
+      case BUILT_IN_MUL_OVERFLOW_P:
+       return 3;
+
       default:;
        return lookup_attribute ("type generic",
                                 TYPE_ATTRIBUTES (TREE_TYPE (fn))) != 0;
@@ -7606,14 +7612,14 @@ build_over_call (struct z_candidate *cand, int flags, tsubst_flags_t complain)
   for (; arg_index < vec_safe_length (args); ++arg_index)
     {
       tree a = (*args)[arg_index];
-      if (magic == 2)
+      if ((magic == 3 && arg_index == 2) || magic == 2)
        {
          /* Do no conversions for certain magic varargs.  */
          a = mark_type_use (a);
          if (TREE_CODE (a) == FUNCTION_DECL && reject_gcc_builtin (a))
            return error_mark_node;
        }
-      else if (magic == 1)
+      else if (magic != 0)
        /* For other magic varargs only do decay_conversion.  */
        a = decay_conversion (a, complain);
       else if (DECL_CONSTRUCTOR_P (fn)

diff --git a/gcc/testsuite/ChangeLog b/gcc/testsuite/ChangeLog
index 0276069ce1fbaf82d0203aa463ebdb6a18736772..589657bf2e91a23116130c99cd83feda4a9c7ee6 100644 (file)
--- a/gcc/testsuite/ChangeLog
+++ b/gcc/testsuite/ChangeLog
@@ -1,5 +1,8 @@
 2016-06-24  Jakub Jelinek  <jakub@redhat.com>
 
+       * c-c++-common/torture/builtin-arith-overflow-p-19.c: Run for C++ too.
+       * g++.dg/ext/builtin-arith-overflow-2.C: New test.
+
        * c-c++-common/builtin-arith-overflow-1.c (generic_wrong_type, f3,
        f4): Adjust expected diagnostics.
        * c-c++-common/torture/builtin-arith-overflow.h (TP): New macro.

diff --git a/gcc/testsuite/c-c++-common/torture/builtin-arith-overflow-p-19.c b/gcc/testsuite/c-c++-common/torture/builtin-arith-overflow-p-19.c
index 38f6d07536e6d24645ac7189799668c38b70659c..0fd8e69dd820a7441556d12415e24dd6cc8ff2af 100644 (file)
--- a/gcc/testsuite/c-c++-common/torture/builtin-arith-overflow-p-19.c
+++ b/gcc/testsuite/c-c++-common/torture/builtin-arith-overflow-p-19.c
@@ -1,5 +1,5 @@
 /* Test __builtin_{add,sub,mul}_overflow_p.  */
-/* { dg-do run { target c } } */
+/* { dg-do run } */
 /* { dg-skip-if "" { ! run_expensive_tests }  { "*" } { "-O0" "-O2" } } */
 
 #include "builtin-arith-overflow.h"

diff --git a/gcc/testsuite/g++.dg/ext/builtin-arith-overflow-2.C b/gcc/testsuite/g++.dg/ext/builtin-arith-overflow-2.C
new file mode 100644 (file)
index 0000000..340ab77
--- /dev/null
+++ b/gcc/testsuite/g++.dg/ext/builtin-arith-overflow-2.C
@@ -0,0 +1,53 @@
+// { dg-do run }
+// { dg-options "-O2" }
+
+struct A { int i : 1; };
+struct B { int j : 3; };
+
+template <typename S>
+int
+foo (int x, int y)
+{
+  A a = {};
+  S s = {};
+  return __builtin_add_overflow_p (x, y, a.i) + 2 * __builtin_mul_overflow_p (x, y, s.j);
+}
+
+__attribute__((noinline, noclone)) int
+bar (int x, int y)
+{
+  return foo <B> (x, y);
+}
+
+#if __cplusplus >= 201402L
+template <typename S>
+constexpr int
+baz (int x, int y)
+{
+  A a = {};
+  S s = {};
+  return __builtin_add_overflow_p (x, y, a.i) + 2 * __builtin_mul_overflow_p (x, y, s.j);
+}
+
+constexpr int t1 = baz <B> (0, 0);
+constexpr int t2 = baz <B> (1, -1);
+constexpr int t3 = baz <B> (1, -4);
+constexpr int t4 = baz <B> (-4, 4);
+constexpr int t5 = baz <B> (4, 2);
+static_assert (t1 == 0, "");
+static_assert (t2 == 0, "");
+static_assert (t3 == 1, "");
+static_assert (t4 == 2, "");
+static_assert (t5 == 3, "");
+#endif
+
+int
+main ()
+{
+  if (bar (0, 0) != 0
+      || bar (-1, 1) != 0
+      || bar (-4, 1) != 1
+      || bar (4, -4) != 2
+      || bar (2, 4) != 3)
+    __builtin_abort ();
+}