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authorChristopher Faylor <me+cygwin@cgf.cx>2000-02-17 19:39:46 +0000
committerChristopher Faylor <me+cygwin@cgf.cx>2000-02-17 19:39:46 +0000
commit43b55bace5fad27af5da7a99784667363b92c45d (patch)
tree17fe82f6ba0d93b76d10dd73d4945ab81b69db40 /newlib/libc/stdlib/__exp10.c
parent8dabd7496a9eeaca2a7180c0a176059ba9229bb2 (diff)
downloadgdb-43b55bace5fad27af5da7a99784667363b92c45d.tar.gz
import newlib-2000-02-17 snapshotnewlib-2000-02-17SNAPSHOT
Diffstat (limited to 'newlib/libc/stdlib/__exp10.c')
-rw-r--r--newlib/libc/stdlib/__exp10.c29
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 00000000000..967362347e7
--- /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;
+ }
+}