Index: fusl/src/math/exp10f.c |
diff --git a/fusl/src/math/exp10f.c b/fusl/src/math/exp10f.c |
new file mode 100644 |
index 0000000000000000000000000000000000000000..7a8d447033eb73d7456cff6ab95d813f28e015ca |
--- /dev/null |
+++ b/fusl/src/math/exp10f.c |
@@ -0,0 +1,23 @@ |
+#define _GNU_SOURCE |
+#include <math.h> |
+#include <stdint.h> |
+#include "libc.h" |
+ |
+float exp10f(float x) |
+{ |
+ static const float p10[] = { |
+ 1e-7f, 1e-6f, 1e-5f, 1e-4f, 1e-3f, 1e-2f, 1e-1f, |
+ 1, 1e1, 1e2, 1e3, 1e4, 1e5, 1e6, 1e7 |
+ }; |
+ float n, y = modff(x, &n); |
+ union {float f; uint32_t i;} u = {n}; |
+ /* fabsf(n) < 8 without raising invalid on nan */ |
+ if ((u.i>>23 & 0xff) < 0x7f+3) { |
+ if (!y) return p10[(int)n+7]; |
+ y = exp2f(3.32192809488736234787031942948939f * y); |
+ return y * p10[(int)n+7]; |
+ } |
+ return exp2(3.32192809488736234787031942948939 * x); |
+} |
+ |
+weak_alias(exp10f, pow10f); |