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author | Alon Zakai <alonzakai@gmail.com> | 2014-01-15 17:01:19 -0800 |
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committer | Alon Zakai <alonzakai@gmail.com> | 2014-01-15 17:01:19 -0800 |
commit | c42b937808924f6b922b29d2e0fd1fe1d1b0411c (patch) | |
tree | 4027d435b6638a7e72b9519990298fb9314ecc96 /system/lib/libc/musl/src/math/ilogbf.c | |
parent | 8478d6aee54d6c52de16d8c58309534afbf5bf9e (diff) | |
parent | e5ccf17e84e7a5102bf9e05ffef01e6672b4c15a (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.c | 26 |
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; +} |