Add a "fork" of musl as //fusl.
This is musl verbatim at d5f8394f6ea9549607567bd92de12a2446c15614.
See http://www.musl-libc.org/.
R=kulakowski@chromium.org
Review URL: https://codereview.chromium.org/1573973002 .
diff --git a/fusl/src/math/cosl.c b/fusl/src/math/cosl.c
new file mode 100644
index 0000000..79c41c7
--- /dev/null
+++ b/fusl/src/math/cosl.c
@@ -0,0 +1,39 @@
+#include "libm.h"
+
+#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
+long double cosl(long double x) {
+ return cos(x);
+}
+#elif (LDBL_MANT_DIG == 64 || LDBL_MANT_DIG == 113) && LDBL_MAX_EXP == 16384
+long double cosl(long double x)
+{
+ union ldshape u = {x};
+ unsigned n;
+ long double y[2], hi, lo;
+
+ u.i.se &= 0x7fff;
+ if (u.i.se == 0x7fff)
+ return x - x;
+ x = u.f;
+ if (x < M_PI_4) {
+ if (u.i.se < 0x3fff - LDBL_MANT_DIG)
+ /* raise inexact if x!=0 */
+ return 1.0 + x;
+ return __cosl(x, 0);
+ }
+ n = __rem_pio2l(x, y);
+ hi = y[0];
+ lo = y[1];
+ switch (n & 3) {
+ case 0:
+ return __cosl(hi, lo);
+ case 1:
+ return -__sinl(hi, lo, 1);
+ case 2:
+ return -__cosl(hi, lo);
+ case 3:
+ default:
+ return __sinl(hi, lo, 1);
+ }
+}
+#endif
