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authorRoland McGrath <roland@gnu.org>1996-03-21 15:20:37 +0000
committerRoland McGrath <roland@gnu.org>1996-03-21 15:20:37 +0000
commitce563359aff66775c71c3e84e7d06a69c199eac0 (patch)
tree5d131b8826fba365414fafd25ee7d61eaba7ef0b /sysdeps/i386
parent38bb44bc19539b14a22a2e931c001c58b6cb1b95 (diff)
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Wed Mar 20 11:28:49 1996 Andreas Schwab <schwab@issan.informatik.uni-dortmund.de>
	* stdio-common/printf.h, stdio-common/printf_fp.c,
	stdio-common/vfprintf.c: Place const in parameter list at
	correct place.

Wed Mar 20 23:58.12 1996  Ulrich Drepper <drepper@gnu.ai.mit.edu>

	* sysdeps/i386/ldbl2mpn.c: Copy of former version of
	sysdeps/ieee754/ldbl2mpn.c.
	* sysdeps/ieee754/ldbl2mpn.c: Remove i386 specific unification.
	Reported by Andreas Schwab.

Wed Mar 20 19:58:43 1996  Roland McGrath  <roland@charlie-brown.gnu.ai.mit.edu>

	* version.c: Include version.h to define RELEASE and VERSION macros.
	(__libc_release, __libc_version): Use them.
	* locale/SYS_libc.c (_libc_intl_domainname): Include ../version.h and
	use VERSION to define domainname as `SYS_GNU_libc-VERSION'.
	* Make-dist (rel+vers): Snarf the macro values from version.h.

	* MakeTAGS (extract): Pass $(XGETTEXTFLAGS-$(@F)).
	(XGETTEXTFLAGS-siglist.pot, XGETTEXTFLAGS-errlist.pot): New variables;
	pass -a for these files.

	* Makerules (po/%.pot): Depend on FORCE target so recursive make is
	always run.
Diffstat (limited to 'sysdeps/i386')
-rw-r--r--sysdeps/i386/ldbl2mpn.c101
1 files changed, 101 insertions, 0 deletions
diff --git a/sysdeps/i386/ldbl2mpn.c b/sysdeps/i386/ldbl2mpn.c
new file mode 100644
index 0000000000..8db73cd27b
--- /dev/null
+++ b/sysdeps/i386/ldbl2mpn.c
@@ -0,0 +1,101 @@
+/* Copyright (C) 1995, 1996 Free Software Foundation, Inc.
+This file is part of the GNU C Library.
+
+The GNU C Library is free software; you can redistribute it and/or
+modify it under the terms of the GNU Library General Public License as
+published by the Free Software Foundation; either version 2 of the
+License, or (at your option) any later version.
+
+The GNU C Library is distributed in the hope that it will be useful,
+but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
+Library General Public License for more details.
+
+You should have received a copy of the GNU Library General Public
+License along with the GNU C Library; see the file COPYING.LIB.  If
+not, write to the Free Software Foundation, Inc., 675 Mass Ave,
+Cambridge, MA 02139, USA.  */
+
+#include "gmp.h"
+#include "gmp-impl.h"
+#include "longlong.h"
+#include "ieee754.h"
+#include <float.h>
+#include <stdlib.h>
+
+/* Convert a `long double' in IEEE854 standard double-precision format to a
+   multi-precision integer representing the significand scaled up by its
+   number of bits (64 for long double) and an integral power of two
+   (MPN frexpl). */
+
+mp_size_t
+__mpn_extract_long_double (mp_ptr res_ptr, mp_size_t size,
+			   int *expt, int *is_neg,
+			   long double value)
+{
+  union ieee854_long_double u;
+  u.d = value;
+
+  *is_neg = u.ieee.negative;
+  *expt = (int) u.ieee.exponent - IEEE854_LONG_DOUBLE_BIAS;
+
+#if BITS_PER_MP_LIMB == 32
+  res_ptr[0] = u.ieee.mantissa1; /* Low-order 32 bits of fraction.  */
+  res_ptr[1] = u.ieee.mantissa0; /* High-order 32 bits.  */
+  #define N 2
+#elif BITS_PER_MP_LIMB == 64
+  /* Hopefully the compiler will combine the two bitfield extracts
+     and this composition into just the original quadword extract.  */
+  res_ptr[0] = ((unsigned long int) u.ieee.mantissa0 << 32) | u.ieee.mantissa1;
+  #define N 1
+#else
+  #error "mp_limb size " BITS_PER_MP_LIMB "not accounted for"
+#endif
+
+  if (u.ieee.exponent == 0)
+    {
+      /* A biased exponent of zero is a special case.
+	 Either it is a zero or it is a denormal number.  */
+      if (res_ptr[0] == 0 && res_ptr[N - 1] == 0) /* Assumes N<=2.  */
+	/* It's zero.  */
+	*expt = 0;
+      else
+	{
+          /* It is a denormal number, meaning it has no implicit leading
+  	     one bit, and its exponent is in fact the format minimum.  */
+	  int cnt;
+
+	  /* One problem with Intel's 80-bit format is that the explicit
+	     leading one in the normalized representation has to be zero
+	     for denormalized number.  If it is one, the number is according
+	     to Intel's specification an invalid number.  We make the
+	     representation unique by explicitly clearing this bit.  */
+	  res_ptr[N - 1] &= ~(1L << ((LDBL_MANT_DIG - 1) % BITS_PER_MP_LIMB));
+
+	  if (res_ptr[N - 1] != 0)
+	    {
+	      count_leading_zeros (cnt, res_ptr[N - 1]);
+	      if (cnt != 0)
+		{
+#if N == 2
+	          res_ptr[N - 1] = res_ptr[N - 1] << cnt
+			           | (res_ptr[0] >> (BITS_PER_MP_LIMB - cnt));
+	          res_ptr[0] <<= cnt;
+#else
+	          res_ptr[N - 1] <<= cnt;
+#endif
+		}
+	      *expt = LDBL_MIN_EXP - 1 - cnt;
+	    }
+	  else
+	    {
+	      count_leading_zeros (cnt, res_ptr[0]);
+	      res_ptr[N - 1] = res_ptr[0] << cnt;
+	      res_ptr[0] = 0;
+	      *expt = LDBL_MIN_EXP - 1 - BITS_PER_MP_LIMB - cnt;
+	    }
+	}
+    }
+
+  return N;
+}