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Diffstat (limited to 'sysdeps/i386/fpu/e_acosl.c')
-rw-r--r--sysdeps/i386/fpu/e_acosl.c25
1 files changed, 25 insertions, 0 deletions
diff --git a/sysdeps/i386/fpu/e_acosl.c b/sysdeps/i386/fpu/e_acosl.c
new file mode 100644
index 0000000000..0c3e03945a
--- /dev/null
+++ b/sysdeps/i386/fpu/e_acosl.c
@@ -0,0 +1,25 @@
+/*
+ * Written by J.T. Conklin <jtc@netbsd.org>.
+ * Public domain.
+ *
+ * Adapted for `long double' by Ulrich Drepper <drepper@cygnus.com>.
+ */
+
+#include <math_private.h>
+
+long double
+__ieee754_acosl (long double x)
+{
+ long double res;
+
+ /* acosl = atanl (sqrtl(1 - x^2) / x) */
+ asm ( "fld %%st\n"
+ "fmul %%st(0)\n" /* x^2 */
+ "fld1\n"
+ "fsubp\n" /* 1 - x^2 */
+ "fsqrt\n" /* sqrtl (1 - x^2) */
+ "fxch %%st(1)\n"
+ "fpatan"
+ : "=t" (res) : "0" (x) : "st(1)");
+ return res;
+}