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diff --git a/libgcc/config/s390/32/_fixunstfdi.c b/libgcc/config/s390/32/_fixunstfdi.c
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+/* Definitions of target machine for GNU compiler, for IBM S/390
+ Copyright (C) 1999, 2000, 2001, 2007, 2008 and 2009
+ Free Software Foundation, Inc.
+ Contributed by Hartmut Penner (hpenner@de.ibm.com) and
+ Ulrich Weigand (uweigand@de.ibm.com).
+
+This file is part of GCC.
+
+GCC is free software; you can redistribute it and/or modify it under
+the terms of the GNU General Public License as published by the Free
+Software Foundation; either version 3, or (at your option) any later
+version.
+
+GCC 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 General Public License
+for more details.
+
+Under Section 7 of GPL version 3, you are granted additional
+permissions described in the GCC Runtime Library Exception, version
+3.1, as published by the Free Software Foundation.
+
+You should have received a copy of the GNU General Public License and
+a copy of the GCC Runtime Library Exception along with this program;
+see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
+<http://www.gnu.org/licenses/>. */
+
+#define EXPD(fp) (((fp.l.i[0]) >> 16) & 0x7FFF)
+#define EXPONENT_BIAS 16383
+#define MANTISSA_BITS 112
+#define PRECISION (MANTISSA_BITS + 1)
+#define SIGNBIT 0x80000000
+#define SIGND(fp) ((fp.l.i[0]) & SIGNBIT)
+#define MANTD_HIGH_LL(fp) ((fp.ll[0] & HIGH_LL_FRAC_MASK) | HIGH_LL_UNIT_BIT)
+#define MANTD_LOW_LL(fp) (fp.ll[1])
+#define FRACD_ZERO_P(fp) (!fp.ll[1] && !(fp.ll[0] & HIGH_LL_FRAC_MASK))
+#define HIGH_LL_FRAC_BITS 48
+#define HIGH_LL_UNIT_BIT ((UDItype_x)1 << HIGH_LL_FRAC_BITS)
+#define HIGH_LL_FRAC_MASK (HIGH_LL_UNIT_BIT - 1)
+
+typedef int DItype_x __attribute__ ((mode (DI)));
+typedef unsigned int UDItype_x __attribute__ ((mode (DI)));
+typedef int SItype_x __attribute__ ((mode (SI)));
+typedef unsigned int USItype_x __attribute__ ((mode (SI)));
+
+union double_long {
+ long double d;
+ struct {
+ SItype_x i[4]; /* 32 bit parts: 0 upper ... 3 lowest */
+ } l;
+ UDItype_x ll[2]; /* 64 bit parts: 0 upper, 1 lower */
+};
+
+UDItype_x __fixunstfdi (long double a1);
+
+/* convert double to unsigned int */
+UDItype_x
+__fixunstfdi (long double a1)
+{
+ register union double_long dl1;
+ register int exp;
+ register UDItype_x l;
+
+ dl1.d = a1;
+
+ /* +/- 0, denormalized, negative */
+ if (!EXPD (dl1) || SIGND(dl1))
+ return 0;
+
+ /* The exponent - considered the binary point at the right end of
+ the mantissa. */
+ exp = EXPD (dl1) - EXPONENT_BIAS - MANTISSA_BITS;
+
+ /* number < 1: If the mantissa would need to be right-shifted more bits than
+ its size (plus the implied one bit on the left) the result would be
+ zero. */
+ if (exp <= -PRECISION)
+ return 0;
+
+ /* NaN: All exponent bits set and a nonzero fraction. */
+ if ((EXPD(dl1) == 0x7fff) && !FRACD_ZERO_P (dl1))
+ return 0x0ULL;
+
+ /* One extra bit is needed for the unit bit which is appended by
+ MANTD_HIGH_LL on the left of the matissa. */
+ exp += HIGH_LL_FRAC_BITS + 1;
+
+ /* If the result would still need a left shift it will be too large
+ to be represented. */
+ if (exp > 0)
+ return 0xFFFFFFFFFFFFFFFFULL;
+
+ l = MANTD_LOW_LL (dl1) >> (HIGH_LL_FRAC_BITS + 1)
+ | MANTD_HIGH_LL (dl1) << (64 - (HIGH_LL_FRAC_BITS + 1));
+
+ return l >> -exp;
+}