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authorAlon Zakai <alonzakai@gmail.com>2014-01-15 17:01:19 -0800
committerAlon Zakai <alonzakai@gmail.com>2014-01-15 17:01:19 -0800
commitc42b937808924f6b922b29d2e0fd1fe1d1b0411c (patch)
tree4027d435b6638a7e72b9519990298fb9314ecc96 /system/lib/libc/musl/src/math/ilogbf.c
parent8478d6aee54d6c52de16d8c58309534afbf5bf9e (diff)
parente5ccf17e84e7a5102bf9e05ffef01e6672b4c15a (diff)
Merge branch 'incoming'
Diffstat (limited to 'system/lib/libc/musl/src/math/ilogbf.c')
-rw-r--r--system/lib/libc/musl/src/math/ilogbf.c26
1 files changed, 26 insertions, 0 deletions
diff --git a/system/lib/libc/musl/src/math/ilogbf.c b/system/lib/libc/musl/src/math/ilogbf.c
new file mode 100644
index 00000000..e23ba209
--- /dev/null
+++ b/system/lib/libc/musl/src/math/ilogbf.c
@@ -0,0 +1,26 @@
+#include <limits.h>
+#include "libm.h"
+
+int ilogbf(float x)
+{
+ #pragma STDC FENV_ACCESS ON
+ union {float f; uint32_t i;} u = {x};
+ uint32_t i = u.i;
+ int e = i>>23 & 0xff;
+
+ if (!e) {
+ i <<= 9;
+ if (i == 0) {
+ FORCE_EVAL(0/0.0f);
+ return FP_ILOGB0;
+ }
+ /* subnormal x */
+ for (e = -0x7f; i>>31 == 0; e--, i<<=1);
+ return e;
+ }
+ if (e == 0xff) {
+ FORCE_EVAL(0/0.0f);
+ return i<<9 ? FP_ILOGBNAN : INT_MAX;
+ }
+ return e - 0x7f;
+}