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authorAndreas Jaeger <aj@suse.de>2012-04-18 09:46:20 +0200
committerAndreas Jaeger <aj@suse.de>2012-04-18 14:31:43 +0200
commit7a99a614618a92b01715733d34b3320d75d9e997 (patch)
treeb40ebb9cbcb2f2abc260e9307ee468f027360a4f /sysdeps/ieee754/ldbl-128/e_ilogbl.c
parente5270c239d7515194b880bbef675d34bcc64139b (diff)
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Finish ilogb changes
[BZ# 6794] * sysdeps/ieee754/ldbl-96/s_ilogbl.c: Moved to ... * sysdeps/ieee754/ldbl-96/e_ilogbl.c: ... here. Rename __ilogbl to __ieee754_ilogbl and remove weak_alias. * sysdeps/ieee754/ldbl-128/s_ilogbl.c: Moved to ... * sysdeps/ieee754/ldbl-128/e_ilogbl.c: ... here. Rename __ilogbl to __ieee754_ilogbl and remove weak_alias. * sysdeps/ieee754/ldbl-64-128/s_ilogbl.c: Moved to ... * sysdeps/ieee754/ldbl-64-128/e_ilogbl.c: ... here. * sysdeps/sparc/sparc64/soft-fp/s_ilogbl.c: Moved to ... * sysdeps/sparc/sparc64/soft-fp/e_ilogbl.c: ... here. Rename __ilogbl to __ieee754_ilogbl and remove weak_alias.
Diffstat (limited to 'sysdeps/ieee754/ldbl-128/e_ilogbl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128/e_ilogbl.c56
1 files changed, 56 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128/e_ilogbl.c b/sysdeps/ieee754/ldbl-128/e_ilogbl.c
new file mode 100644
index 0000000..0a47649
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128/e_ilogbl.c
@@ -0,0 +1,56 @@
+/* s_ilogbl.c -- long double version of s_ilogb.c.
+ * Conversion to IEEE quad long double by Jakub Jelinek, jj@ultra.linux.cz.
+ */
+
+/*
+ * ====================================================
+ * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
+ *
+ * Developed at SunPro, a Sun Microsystems, Inc. business.
+ * Permission to use, copy, modify, and distribute this
+ * software is freely granted, provided that this notice
+ * is preserved.
+ * ====================================================
+ */
+
+#if defined(LIBM_SCCS) && !defined(lint)
+static char rcsid[] = "$NetBSD: $";
+#endif
+
+/* ilogbl(long double x)
+ * return the binary exponent of non-zero x
+ * ilogbl(0) = FP_ILOGB0
+ * ilogbl(NaN) = FP_ILOGBNAN (no signal is raised)
+ * ilogbl(+-Inf) = INT_MAX (no signal is raised)
+ */
+
+#include <limits.h>
+#include <math.h>
+#include <math_private.h>
+
+int __ieee754_ilogbl (long double x)
+{
+ int64_t hx,lx;
+ int ix;
+
+ GET_LDOUBLE_WORDS64(hx,lx,x);
+ hx &= 0x7fffffffffffffffLL;
+ if(hx <= 0x0001000000000000LL) {
+ if((hx|lx)==0)
+ return FP_ILOGB0; /* ilogbl(0) = FP_ILOGB0 */
+ else /* subnormal x */
+ if(hx==0) {
+ for (ix = -16431; lx>0; lx<<=1) ix -=1;
+ } else {
+ for (ix = -16382, hx<<=15; hx>0; hx<<=1) ix -=1;
+ }
+ return ix;
+ }
+ else if (hx<0x7fff000000000000LL) return (hx>>48)-0x3fff;
+ else if (FP_ILOGBNAN != INT_MAX) {
+ /* ISO C99 requires ilogbl(+-Inf) == INT_MAX. */
+ if (((hx^0x7fff000000000000LL)|lx) == 0)
+ return INT_MAX;
+ }
+ return FP_ILOGBNAN;
+}