x86_64: add fenv support from glibc

1 files changed, 30 insertions, 0 deletions

diff --git a/libm/x86_64/fesetexcept.c b/libm/x86_64/fesetexcept.c
new file mode 100644
index 000000000..ee63c3f80
--- /dev/null
+++ b/libm/x86_64/fesetexcept.c
@@ -0,0 +1,30 @@
+/* Set given exception flags.  x86_64 version.
+   Copyright (C) 2016-2017 Free Software Foundation, Inc.
+
+   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, see
+   <http://www.gnu.org/licenses/>.  */
+
+#include <fenv.h>
+
+int
+fesetexcept (int excepts)
+{
+  unsigned int mxcsr;
+
+  __asm__ ("stmxcsr %0" : "=m" (*&mxcsr));
+  mxcsr |= excepts & FE_ALL_EXCEPT;
+  __asm__ ("ldmxcsr %0" : : "m" (*&mxcsr));
+
+  return 0;
+}