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authorPikalaxALT <pikalaxalt@gmail.com>2017-12-15 09:38:53 -0500
committerPikalaxALT <pikalaxalt@gmail.com>2017-12-15 09:39:34 -0500
commitf95a4a932476be2ba99e2fd081e8d2bc6ea12813 (patch)
tree75f67192cb2d7b7b575c94edda318e475239b63c /newlib/libc/stdlib/__exp10.c
parentf60aca96985e68c7d8a52eb7bc955fb80e132f73 (diff)
Import newlib and create makefile
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 0000000..9673623
--- /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;
+ }
+}