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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 13:54:38 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-04-17 13:54:38 +0000
commit8c1ab65c0f548d20b7f177bdb736daaf603340e1 (patch)
treedf55b7e75bf43f2bf500845b105afe3ac3a5157e /libc-top-half/musl/src/math/ilogbl.c
parentInitial commit. (diff)
downloadwasi-libc-upstream/0.0_git20221206.8b7148f.tar.xz
wasi-libc-upstream/0.0_git20221206.8b7148f.zip
Adding upstream version 0.0~git20221206.8b7148f.upstream/0.0_git20221206.8b7148f
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'libc-top-half/musl/src/math/ilogbl.c')
-rw-r--r--libc-top-half/musl/src/math/ilogbl.c55
1 files changed, 55 insertions, 0 deletions
diff --git a/libc-top-half/musl/src/math/ilogbl.c b/libc-top-half/musl/src/math/ilogbl.c
new file mode 100644
index 0000000..7b1a9cf
--- /dev/null
+++ b/libc-top-half/musl/src/math/ilogbl.c
@@ -0,0 +1,55 @@
+#include <limits.h>
+#include "libm.h"
+
+#if LDBL_MANT_DIG == 53 && LDBL_MAX_EXP == 1024
+int ilogbl(long double x)
+{
+ return ilogb(x);
+}
+#elif LDBL_MANT_DIG == 64 && LDBL_MAX_EXP == 16384
+int ilogbl(long double x)
+{
+ #pragma STDC FENV_ACCESS ON
+ union ldshape u = {x};
+ uint64_t m = u.i.m;
+ int e = u.i.se & 0x7fff;
+
+ if (!e) {
+ if (m == 0) {
+ FORCE_EVAL(0/0.0f);
+ return FP_ILOGB0;
+ }
+ /* subnormal x */
+ for (e = -0x3fff+1; m>>63 == 0; e--, m<<=1);
+ return e;
+ }
+ if (e == 0x7fff) {
+ FORCE_EVAL(0/0.0f);
+ return m<<1 ? FP_ILOGBNAN : INT_MAX;
+ }
+ return e - 0x3fff;
+}
+#elif LDBL_MANT_DIG == 113 && LDBL_MAX_EXP == 16384
+int ilogbl(long double x)
+{
+ #pragma STDC FENV_ACCESS ON
+ union ldshape u = {x};
+ int e = u.i.se & 0x7fff;
+
+ if (!e) {
+ if (x == 0) {
+ FORCE_EVAL(0/0.0f);
+ return FP_ILOGB0;
+ }
+ /* subnormal x */
+ x *= 0x1p120;
+ return ilogbl(x) - 120;
+ }
+ if (e == 0x7fff) {
+ FORCE_EVAL(0/0.0f);
+ u.i.se = 0;
+ return u.f ? FP_ILOGBNAN : INT_MAX;
+ }
+ return e - 0x3fff;
+}
+#endif