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-rw-r--r--vendor/libm/src/math/ilogbf.rs31
1 files changed, 31 insertions, 0 deletions
diff --git a/vendor/libm/src/math/ilogbf.rs b/vendor/libm/src/math/ilogbf.rs
new file mode 100644
index 000000000..b384fa4b2
--- /dev/null
+++ b/vendor/libm/src/math/ilogbf.rs
@@ -0,0 +1,31 @@
+const FP_ILOGBNAN: i32 = -1 - 0x7fffffff;
+const FP_ILOGB0: i32 = FP_ILOGBNAN;
+
+pub fn ilogbf(x: f32) -> i32 {
+ let mut i = x.to_bits();
+ let e = ((i >> 23) & 0xff) as i32;
+
+ if e == 0 {
+ i <<= 9;
+ if i == 0 {
+ force_eval!(0.0 / 0.0);
+ return FP_ILOGB0;
+ }
+ /* subnormal x */
+ let mut e = -0x7f;
+ while (i >> 31) == 0 {
+ e -= 1;
+ i <<= 1;
+ }
+ e
+ } else if e == 0xff {
+ force_eval!(0.0 / 0.0);
+ if (i << 9) != 0 {
+ FP_ILOGBNAN
+ } else {
+ i32::max_value()
+ }
+ } else {
+ e - 0x7f
+ }
+}