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authorAlon Zakai <alonzakai@gmail.com>2014-01-13 16:55:19 -0800
committerAlon Zakai <alonzakai@gmail.com>2014-01-13 16:56:03 -0800
commitcd1edebb5034ea52396a5b68304e84ae80878740 (patch)
tree6a6f8364ea74985d11c4f6ff74e5b80e08dc849d /system/lib/libc/musl/src/math/ilogbf.c
parentaf59788f8b7b76515e36bee1bf66edf497b801db (diff)
parent2914deb17f3857bb02eeec87a58a3ed6d4a8853a (diff)
Merge branch 'incoming' of github.com:kripken/emscripten into incoming1.8.8
conflicts: tests/test_core.py tools/shared.py
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;
+}