import newlib-2000-02-17 snapshot

1 files changed, 29 insertions, 0 deletions

diff --git a/newlib/libc/stdlib/__exp10.c b/newlib/libc/stdlib/__exp10.c
new file mode 100644
index 000000000..967362347
--- /dev/null
+++ b/newlib/libc/stdlib/__exp10.c
@@ -0,0 +1,29 @@
+/*
+ * compute 10**x by successive squaring.
+ */
+
+#include <_ansi.h>
+
+double
+_DEFUN (__exp10, (x),
+	unsigned x)
+{
+  static _CONST double powtab[] =
+  {1.0,
+   10.0,
+   100.0,
+   1000.0,
+   10000.0};
+
+  if (x < (sizeof (powtab) / sizeof (double)))
+      return powtab[x];
+  else if (x & 1)
+    {
+      return 10.0 * __exp10 (x - 1);
+    }
+  else
+    {
+      double n = __exp10 (x / 2);
+      return n * n;
+    }
+}