New module 'floorf-ieee'.

[gnulib.git] / tests / test-floorf-ieee.c

diff --git a/tests/test-floorf-ieee.c b/tests/test-floorf-ieee.c
new file mode 100644 (file)
index 0000000..da13848
--- /dev/null
+++ b/tests/test-floorf-ieee.c
@@ -0,0 +1,45 @@
+/* Test of rounding towards negative infinity.
+   Copyright (C) 2010 Free Software Foundation, Inc.
+
+   This program is free software: you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
+
+#include <config.h>
+
+#include <math.h>
+
+#include "minus-zero.h"
+#include "macros.h"
+
+/* If IEEE compliance was not requested, the ICC compiler inlines its
+   own floorf assembly that turns -0.0f to 0.0f; but that is a correct
+   result when IEEE is not enforced.  To avoid spurious failure, we
+   have to provide this dummy function in order to outsmart ICC's
+   inlining, and call our floorf through a function pointer.  */
+static float
+dummy (float f)
+{
+  return 0;
+}
+
+int
+main (int argc, char **argv _GL_UNUSED)
+{
+  float (*my_floorf) (float) = argc ? floorf : dummy;
+
+  /* Zero.  */
+  ASSERT (!signbit (my_floorf (0.0f)));
+  ASSERT (!!signbit (my_floorf (minus_zerof)) == !!signbit (minus_zerof));
+
+  return 0;
+}