import newlib-2000-02-17 snapshot

1 files changed, 81 insertions, 0 deletions

diff --git a/newlib/libm/mathfp/sf_ldexp.c b/newlib/libm/mathfp/sf_ldexp.c
new file mode 100644
index 000000000..6b6c2c00b
--- /dev/null
+++ b/newlib/libm/mathfp/sf_ldexp.c
@@ -0,0 +1,81 @@
+
+/* @(#)z_ldexpf.c 1.0 98/08/13 */
+/******************************************************************
+ * ldexp
+ *
+ * Input:
+ *   d - a floating point value
+ *   e - an exponent value
+ *
+ * Output:
+ *   A floating point value f such that f = d * 2 ^ e.
+ *
+ * Description:
+ *   This function creates a floating point number f such that
+ *   f = d * 2 ^ e.
+ *
+ *****************************************************************/
+
+#include <float.h>
+#include "fdlibm.h"
+#include "zmath.h"
+
+#define FLOAT_EXP_OFFS 127
+
+float
+_DEFUN (ldexpf, (float, int),
+        float d _AND
+        int e)
+{
+  int exp;
+  __int32_t wd;
+
+  GET_FLOAT_WORD (wd, d);
+
+  /* Check for special values and then scale d by e. */
+  switch (numtestf (wd))
+    {
+      case NAN:
+        errno = EDOM;
+        break;
+
+      case INF:
+        errno = ERANGE;
+        break;
+
+      case 0:
+        break;
+
+      default:
+        exp = (wd & 0x7f800000) >> 23;
+        exp += e;
+
+        if (exp > FLT_MAX_EXP + FLOAT_EXP_OFFS)
+         {
+           errno = ERANGE;
+           d = z_infinity_f.f;
+         }
+        else if (exp < FLT_MIN_EXP + FLOAT_EXP_OFFS)
+         {
+           errno = ERANGE;
+           d = -z_infinity_f.f;
+         }
+        else
+         {
+           wd &= 0x807fffff;
+           wd |= exp << 23;
+           SET_FLOAT_WORD (d, wd);
+         }
+    }
+
+    return (d);
+}
+
+#ifdef _DOUBLE_IS_32BITS
+
+double ldexp (double x, int e)
+{
+  return (double) ldexpf ((float) x, e);
+}
+
+#endif /* defined(_DOUBLE_IS_32BITS) */