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Diffstat (limited to 'lib/mlibc/options/ansi/musl-generic-math/scalbnf.c')
-rw-r--r--lib/mlibc/options/ansi/musl-generic-math/scalbnf.c31
1 files changed, 31 insertions, 0 deletions
diff --git a/lib/mlibc/options/ansi/musl-generic-math/scalbnf.c b/lib/mlibc/options/ansi/musl-generic-math/scalbnf.c
new file mode 100644
index 0000000..a5ad208
--- /dev/null
+++ b/lib/mlibc/options/ansi/musl-generic-math/scalbnf.c
@@ -0,0 +1,31 @@
+#include <math.h>
+#include <stdint.h>
+
+float scalbnf(float x, int n)
+{
+ union {float f; uint32_t i;} u;
+ float_t y = x;
+
+ if (n > 127) {
+ y *= 0x1p127f;
+ n -= 127;
+ if (n > 127) {
+ y *= 0x1p127f;
+ n -= 127;
+ if (n > 127)
+ n = 127;
+ }
+ } else if (n < -126) {
+ y *= 0x1p-126f * 0x1p24f;
+ n += 126 - 24;
+ if (n < -126) {
+ y *= 0x1p-126f * 0x1p24f;
+ n += 126 - 24;
+ if (n < -126)
+ n = -126;
+ }
+ }
+ u.i = (uint32_t)(0x7f+n)<<23;
+ x = y * u.f;
+ return x;
+}