Implement accurate fma.

1 files changed, 37 insertions, 0 deletions

diff --git a/sysdeps/s390/fpu/s_fma.c b/sysdeps/s390/fpu/s_fma.c
new file mode 100644
index 0000000000..f682362313
--- /dev/null
+++ b/sysdeps/s390/fpu/s_fma.c
@@ -0,0 +1,37 @@
+/* Compute x * y + z as ternary operation.  S/390 version.
+   Copyright (C) 2010 Free Software Foundation, Inc.
+   This file is part of the GNU C Library.
+   Contributed by Jakub Jelinek <jakub@redhat.com>, 2010.
+
+   The GNU C Library is free software; you can redistribute it and/or
+   modify it under the terms of the GNU Lesser General Public
+   License as published by the Free Software Foundation; either
+   version 2.1 of the License, or (at your option) any later version.
+
+   The GNU C Library 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
+   Lesser General Public License for more details.
+
+   You should have received a copy of the GNU Lesser General Public
+   License along with the GNU C Library; if not, write to the Free
+   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
+   02111-1307 USA.  */
+
+#include <math.h>
+
+double
+__fma (double x, double y, double z)
+{
+  double r;
+  asm ("madbr %0,%1,%2" : "=f" (r) : "%f" (x), "fR" (y), "0" (z));
+  return r;
+}
+#ifndef __fma
+weak_alias (__fma, fma)
+#endif
+
+#ifdef NO_LONG_DOUBLE
+strong_alias (__fma, __fmal)
+weak_alias (__fmal, fmal)
+#endif