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Diffstat (limited to 'sysdeps/ieee754/ldbl-128ibm/s_frexpl.c')
-rw-r--r--sysdeps/ieee754/ldbl-128ibm/s_frexpl.c92
1 files changed, 92 insertions, 0 deletions
diff --git a/sysdeps/ieee754/ldbl-128ibm/s_frexpl.c b/sysdeps/ieee754/ldbl-128ibm/s_frexpl.c
new file mode 100644
index 0000000000..fab566da3b
--- /dev/null
+++ b/sysdeps/ieee754/ldbl-128ibm/s_frexpl.c
@@ -0,0 +1,92 @@
+/* s_frexpl.c -- long double version of s_frexp.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
+
+/*
+ * for non-zero x
+ *	x = frexpl(arg,&exp);
+ * return a long double fp quantity x such that 0.5 <= |x| <1.0
+ * and the corresponding binary exponent "exp". That is
+ *	arg = x*2^exp.
+ * If arg is inf, 0.0, or NaN, then frexpl(arg,&exp) returns arg
+ * with *exp=0.
+ */
+
+#include "math.h"
+#include "math_private.h"
+#include <math_ldbl_opt.h>
+
+#ifdef __STDC__
+static const long double
+#else
+static long double
+#endif
+two107 = 162259276829213363391578010288128.0; /* 0x4670000000000000, 0 */
+
+#ifdef __STDC__
+	long double __frexpl(long double x, int *eptr)
+#else
+	long double __frexpl(x, eptr)
+	long double x; int *eptr;
+#endif
+{
+	u_int64_t hx, lx, ix, ixl;
+	int64_t explo;
+	GET_LDOUBLE_WORDS64(hx,lx,x);
+	ixl = 0x7fffffffffffffffULL&lx;
+	ix =  0x7fffffffffffffffULL&hx;
+	*eptr = 0;
+	if(ix>=0x7ff0000000000000ULL||((ix|ixl)==0)) return x;	/* 0,inf,nan */
+	if (ix<0x0010000000000000ULL) {		/* subnormal */
+	    x *= two107;
+	    GET_LDOUBLE_MSW64(hx,x);
+	    ix = hx&0x7fffffffffffffffULL;
+	    *eptr = -107;
+	}
+	*eptr += (ix>>52)-1022;
+
+	if (ixl != 0ULL) {
+	  explo = (ixl>>52) - (ix>>52) + 0x3fe;
+	  if ((ixl&0x7ff0000000000000ULL) == 0LL) {
+	    /* the lower double is a denomal so we need to correct its
+	       mantissa and perhaps its exponent.  */
+	    int cnt;
+
+	    if (sizeof (ixl) == sizeof (long))
+	      cnt = __builtin_clzl (ixl);
+	    else if ((ixl >> 32) != 0)
+	      cnt = __builtin_clzl ((long) (ixl >> 32));
+	    else
+	      cnt = __builtin_clzl ((long) ixl) + 32;
+	    cnt = cnt - 12;
+	    lx = (lx&0x8000000000000000ULL) | ((explo-cnt)<<52)
+	       | ((ixl<<(cnt+1))&0x000fffffffffffffULL);
+	  } else
+	    lx = (lx&0x800fffffffffffffULL) | (explo<<52);
+	} else
+	  lx = 0ULL;
+
+	hx = (hx&0x800fffffffffffffULL) | 0x3fe0000000000000ULL;
+	SET_LDOUBLE_WORDS64(x,hx,lx);
+	return x;
+}
+#ifdef IS_IN_libm
+long_double_symbol (libm, __frexpl, frexpl);
+#else
+long_double_symbol (libc, __frexpl, frexpl);
+#endif