about summary refs log tree commit diff
path: root/sysdeps/i386/fpu/e_acosf.S
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/i386/fpu/e_acosf.S')
-rw-r--r--sysdeps/i386/fpu/e_acosf.S22
1 files changed, 22 insertions, 0 deletions
diff --git a/sysdeps/i386/fpu/e_acosf.S b/sysdeps/i386/fpu/e_acosf.S
new file mode 100644
index 0000000000..50b13fd1bd
--- /dev/null
+++ b/sysdeps/i386/fpu/e_acosf.S
@@ -0,0 +1,22 @@
+/*
+ * Written by J.T. Conklin <jtc@netbsd.org>.
+ * Public domain.
+ * Adapted for float type by Ulrich Drepper <drepper@cygnus.com>.
+ */
+
+#include <machine/asm.h>
+
+RCSID("$NetBSD: $")
+
+/* acos = atan (sqrt(1 - x^2) / x) */
+ENTRY(__ieee754_acosf)
+	flds	4(%esp)			/* x */
+	fld	%st
+	fmul	%st(0)			/* x^2 */
+	fld1
+	fsubp				/* 1 - x^2 */
+	fsqrt				/* sqrt (1 - x^2) */
+	fxch	%st(1)
+	fpatan
+	ret
+END (__ieee754_acosf)