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mq_notify: block all (application) signals in the worker thread
[musl]
/
src
/
math
/
scalbn.c
diff --git
a/src/math/scalbn.c
b/src/math/scalbn.c
index
42a2b29
..
182f561
100644
(file)
--- a/
src/math/scalbn.c
+++ b/
src/math/scalbn.c
@@
-1,35
+1,33
@@
-#include "libm.h"
+#include <math.h>
+#include <stdint.h>
double scalbn(double x, int n)
{
double scalbn(double x, int n)
{
- /* make sure result is stored as double on overflow or underflow */
- volatile double z;
- double scale;
+ union {double f; uint64_t i;} u;
+ double_t y = x;
if (n > 1023) {
if (n > 1023) {
-
x
*= 0x1p1023;
+
y
*= 0x1p1023;
n -= 1023;
if (n > 1023) {
n -= 1023;
if (n > 1023) {
-
x
*= 0x1p1023;
+
y
*= 0x1p1023;
n -= 1023;
n -= 1023;
- if (n > 1023) {
- z = x * 0x1p1023;
- return z;
- }
+ if (n > 1023)
+ n = 1023;
}
} else if (n < -1022) {
}
} else if (n < -1022) {
- x *= 0x1p-1022;
- n += 1022;
+ /* make sure final n < -53 to avoid double
+ rounding in the subnormal range */
+ y *= 0x1p-1022 * 0x1p53;
+ n += 1022 - 53;
if (n < -1022) {
if (n < -1022) {
- x *= 0x1p-1022;
- n += 1022;
- if (n < -1022) {
- z = x * 0x1p-1022;
- return z;
- }
+ y *= 0x1p-1022 * 0x1p53;
+ n += 1022 - 53;
+ if (n < -1022)
+ n = -1022;
}
}
}
}
-
INSERT_WORDS(scale, (uint32_t)(0x3ff+n)<<20, 0)
;
-
z = x * scale
;
- return
z
;
+
u.i = (uint64_t)(0x3ff+n)<<52
;
+
x = y * u.f
;
+ return
x
;
}
}