math: fix logb*.c exceptions now that ilogb raises invalid

[musl] / src / math / logbf.c

diff --git a/src/math/logbf.c b/src/math/logbf.c
index 934827f..950d356 100644 (file)
--- a/src/math/logbf.c
+++ b/src/math/logbf.c
@@ -1,12 +1,10 @@
-#include <limits.h>
 #include "libm.h"
 
-float logbf(float x) {
-       int i = ilogbf(x);
-
-       if (i == FP_ILOGB0)
-               return -1.0f/fabsf(x);
-       if (i == FP_ILOGBNAN || i == INT_MAX)
+float logbf(float x)
+{
+       if (!isfinite(x))
                return x * x;
-       return i;
+       if (x == 0)
+               return -1/(x+0);
+       return ilogbf(x);
 }