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-rw-r--r--lib/mlibc/options/ansi/musl-generic-math/exp10.c26
1 files changed, 26 insertions, 0 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/exp10.c b/lib/mlibc/options/ansi/musl-generic-math/exp10.c
new file mode 100644
index 0000000..47b4dc7
--- /dev/null
+++ b/lib/mlibc/options/ansi/musl-generic-math/exp10.c
@@ -0,0 +1,26 @@
+#define _GNU_SOURCE
+#include <math.h>
+#include <stdint.h>
+#include "weak_alias.h"
+//#include "libc.h"
+
+double exp10(double x)
+{
+ static const double p10[] = {
+ 1e-15, 1e-14, 1e-13, 1e-12, 1e-11, 1e-10,
+ 1e-9, 1e-8, 1e-7, 1e-6, 1e-5, 1e-4, 1e-3, 1e-2, 1e-1,
+ 1, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7, 1e8, 1e9,
+ 1e10, 1e11, 1e12, 1e13, 1e14, 1e15
+ };
+ double n, y = modf(x, &n);
+ union {double f; uint64_t i;} u = {n};
+ /* fabs(n) < 16 without raising invalid on nan */
+ if ((u.i>>52 & 0x7ff) < 0x3ff+4) {
+ if (!y) return p10[(int)n+15];
+ y = exp2(3.32192809488736234787031942948939 * y);
+ return y * p10[(int)n+15];
+ }
+ return pow(10.0, x);
+}
+
+weak_alias(exp10, pow10);