summaryrefslogtreecommitdiff
path: root/libm/src/w_exp.c
diff options
context:
space:
mode:
Diffstat (limited to 'libm/src/w_exp.c')
-rw-r--r--libm/src/w_exp.c48
1 files changed, 48 insertions, 0 deletions
diff --git a/libm/src/w_exp.c b/libm/src/w_exp.c
new file mode 100644
index 0000000..7819ca1
--- /dev/null
+++ b/libm/src/w_exp.c
@@ -0,0 +1,48 @@
+
+/* @(#)w_exp.c 1.4 04/04/22 */
+/*
+ * ====================================================
+ * Copyright (C) 2004 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+/*
+ * wrapper exp(x)
+ */
+
+#include "fdlibm.h"
+
+#ifdef __STDC__
+static const double
+#else
+static double
+#endif
+o_threshold= 7.09782712893383973096e+02, /* 0x40862E42, 0xFEFA39EF */
+u_threshold= -7.45133219101941108420e+02; /* 0xc0874910, 0xD52D3051 */
+
+#ifdef __STDC__
+ double exp(double x) /* wrapper exp */
+#else
+ double exp(x) /* wrapper exp */
+ double x;
+#endif
+{
+#ifdef _IEEE_LIBM
+ return __ieee754_exp(x);
+#else
+ double z;
+ z = __ieee754_exp(x);
+ if(_LIB_VERSION == _IEEE_) return z;
+ if(finite(x)) {
+ if(x>o_threshold)
+ return __kernel_standard(x,x,6); /* exp overflow */
+ else if(x<u_threshold)
+ return __kernel_standard(x,x,7); /* exp underflow */
+ }
+ return z;
+#endif
+}