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diff --git a/gmp-6.3.0/mpn/generic/get_d.c b/gmp-6.3.0/mpn/generic/get_d.c
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+++ b/gmp-6.3.0/mpn/generic/get_d.c
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+/* mpn_get_d -- limbs to double conversion.
+
+   THE FUNCTIONS IN THIS FILE ARE FOR INTERNAL USE ONLY.  THEY'RE ALMOST
+   CERTAIN TO BE SUBJECT TO INCOMPATIBLE CHANGES OR DISAPPEAR COMPLETELY IN
+   FUTURE GNU MP RELEASES.
+
+Copyright 2003, 2004, 2007, 2009, 2010, 2012, 2018 Free Software
+Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP Library is free software; you can redistribute it and/or modify
+it under the terms of either:
+
+  * the GNU Lesser General Public License as published by the Free
+    Software Foundation; either version 3 of the License, or (at your
+    option) any later version.
+
+or
+
+  * the GNU General Public License as published by the Free Software
+    Foundation; either version 2 of the License, or (at your option) any
+    later version.
+
+or both in parallel, as here.
+
+The GNU MP 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 General Public License
+for more details.
+
+You should have received copies of the GNU General Public License and the
+GNU Lesser General Public License along with the GNU MP Library.  If not,
+see https://www.gnu.org/licenses/.  */
+
+#include "config.h"
+
+#if HAVE_FLOAT_H
+#include <float.h>  /* for DBL_MANT_DIG and FLT_RADIX */
+#endif
+
+#include "gmp-impl.h"
+#include "longlong.h"
+
+#ifndef _GMP_IEEE_FLOATS
+#define _GMP_IEEE_FLOATS 0
+#endif
+
+/* To force use of the generic C code for testing, put
+   "#define _GMP_IEEE_FLOATS 0" at this point.  */
+
+
+/* In alpha gcc prior to 3.4, signed DI comparisons involving constants are
+   rearranged from "x < n" to "x+(-n) < 0", which is of course hopelessly
+   wrong if that addition overflows.
+
+   The workaround here avoids this bug by ensuring n is not a literal constant.
+   Note that this is alpha specific.  The offending transformation is/was in
+   alpha.c alpha_emit_conditional_branch() under "We want to use cmpcc/bcc".
+
+   Bizarrely, this happens also with Cray cc on alphaev5-cray-unicosmk2.0.6.X,
+   and has the same solution.  Don't know why or how.  */
+
+#if HAVE_HOST_CPU_FAMILY_alpha				\
+  && ((defined (__GNUC__) && ! __GMP_GNUC_PREREQ(3,4))	\
+      || defined (_CRAY))
+static volatile const long CONST_1024 = 1024;
+static volatile const long CONST_NEG_1023 = -1023;
+static volatile const long CONST_NEG_1022_SUB_53 = -1022 - 53;
+#else
+#define CONST_1024	      (1024)
+#define CONST_NEG_1023	      (-1023)
+#define CONST_NEG_1022_SUB_53 (-1022 - 53)
+#endif
+
+
+/* Return the value {ptr,size}*2^exp, and negative if sign<0.  Must have
+   size>=1, and a non-zero high limb ptr[size-1].
+
+   When we know the fp format, the result is truncated towards zero.  This is
+   consistent with other gmp conversions, like mpz_set_f or mpz_set_q, and is
+   easy to implement and test.
+
+   When we do not know the format, such truncation seems much harder.  One
+   would need to defeat any rounding mode, including round-up.
+
+   It's felt that GMP is not primarily concerned with hardware floats, and
+   really isn't enhanced by getting involved with hardware rounding modes
+   (which could even be some weird unknown style), so something unambiguous and
+   straightforward is best.
+
+
+   The IEEE code below is the usual case, it knows either a 32-bit or 64-bit
+   limb and is done with shifts and masks.  The 64-bit case in particular
+   should come out nice and compact.
+
+   The generic code used to work one bit at a time, which was not only slow,
+   but implicitly relied upon denorms for intermediates, since the lowest bits'
+   weight of a perfectly valid fp number underflows in non-denorm.  Therefore,
+   the generic code now works limb-per-limb, initially creating a number x such
+   that 1 <= x <= BASE.  (BASE is reached only as result of rounding.)  Then
+   x's exponent is scaled with explicit code (not ldexp to avoid libm
+   dependency).  It is a tap-dance to avoid underflow or overflow, beware!
+
+
+   Traps:
+
+   Hardware traps for overflow to infinity, underflow to zero, or unsupported
+   denorms may or may not be taken.  The IEEE code works bitwise and so
+   probably won't trigger them, the generic code works by float operations and
+   so probably will.  This difference might be thought less than ideal, but
+   again its felt straightforward code is better than trying to get intimate
+   with hardware exceptions (of perhaps unknown nature).
+
+
+   Not done:
+
+   mpz_get_d in the past handled size==1 with a cast limb->double.  This might
+   still be worthwhile there (for up to the mantissa many bits), but for
+   mpn_get_d here, the cost of applying "exp" to the resulting exponent would
+   probably use up any benefit a cast may have over bit twiddling.  Also, if
+   the exponent is pushed into denorm range then bit twiddling is the only
+   option, to ensure the desired truncation is obtained.
+
+
+   Other:
+
+   For reference, note that HPPA 8000, 8200, 8500 and 8600 trap FCNV,UDW,DBL
+   to the kernel for values >= 2^63.  This makes it slow, and worse the kernel
+   Linux (what versions?) apparently uses untested code in its trap handling
+   routines, and gets the sign wrong.  We don't use such a limb-to-double
+   cast, neither in the IEEE or generic code.  */
+
+
+
+#undef FORMAT_RECOGNIZED
+
+double
+mpn_get_d (mp_srcptr up, mp_size_t size, mp_size_t sign, long exp)
+{
+  int lshift, nbits;
+  mp_limb_t x, mhi, mlo;
+
+  ASSERT (size >= 0);
+  ASSERT_MPN (up, size);
+  ASSERT (size == 0 || up[size-1] != 0);
+
+  if (size == 0)
+    return 0.0;
+
+  /* Adjust exp to a radix point just above {up,size}, guarding against
+     overflow.  After this exp can of course be reduced to anywhere within
+     the {up,size} region without underflow.  */
+  if (UNLIKELY ((unsigned long) (GMP_NUMB_BITS * size)
+		> ((unsigned long) LONG_MAX - exp)))
+    {
+#if _GMP_IEEE_FLOATS
+      goto ieee_infinity;
+#endif
+
+      /* generic */
+      exp = LONG_MAX;
+    }
+  else
+    {
+      exp += GMP_NUMB_BITS * size;
+    }
+
+#if _GMP_IEEE_FLOATS
+    {
+      union ieee_double_extract u;
+
+      up += size;
+
+#if GMP_LIMB_BITS == 64
+      mlo = up[-1];
+      count_leading_zeros (lshift, mlo);
+
+      exp -= (lshift - GMP_NAIL_BITS) + 1;
+      mlo <<= lshift;
+
+      nbits = GMP_LIMB_BITS - lshift;
+
+      if (nbits < 53 && size > 1)
+	{
+	  x = up[-2];
+	  x <<= GMP_NAIL_BITS;
+	  x >>= nbits;
+	  mlo |= x;
+	  nbits += GMP_NUMB_BITS;
+
+	  if (LIMBS_PER_DOUBLE >= 3 && nbits < 53 && size > 2)
+	    {
+	      x = up[-3];
+	      x <<= GMP_NAIL_BITS;
+	      x >>= nbits;
+	      mlo |= x;
+	      nbits += GMP_NUMB_BITS;
+	    }
+	}
+      mhi = mlo >> (32 + 11);
+      mlo = mlo >> 11;		/* later implicitly truncated to 32 bits */
+#endif
+#if GMP_LIMB_BITS == 32
+      x = *--up;
+      count_leading_zeros (lshift, x);
+
+      exp -= (lshift - GMP_NAIL_BITS) + 1;
+      x <<= lshift;
+      mhi = x >> 11;
+
+      if (lshift < 11)		/* FIXME: never true if NUMB < 20 bits */
+	{
+	  /* All 20 bits in mhi */
+	  mlo = x << 21;
+	  /* >= 1 bit in mlo */
+	  nbits = GMP_LIMB_BITS - lshift - 21;
+	}
+      else
+	{
+	  if (size > 1)
+	    {
+	      nbits = GMP_LIMB_BITS - lshift;
+
+	      x = *--up, size--;
+	      x <<= GMP_NAIL_BITS;
+	      mhi |= x >> nbits >> 11;
+
+	      mlo = x << (GMP_LIMB_BITS - nbits - 11);
+	      nbits = nbits + 11 - GMP_NAIL_BITS;
+	    }
+	  else
+	    {
+	      mlo = 0;
+	      goto done;
+	    }
+	}
+
+      /* Now all needed bits in mhi have been accumulated.  Add bits to mlo.  */
+
+      if (LIMBS_PER_DOUBLE >= 2 && nbits < 32 && size > 1)
+	{
+	  x = up[-1];
+	  x <<= GMP_NAIL_BITS;
+	  x >>= nbits;
+	  mlo |= x;
+	  nbits += GMP_NUMB_BITS;
+
+	  if (LIMBS_PER_DOUBLE >= 3 && nbits < 32 && size > 2)
+	    {
+	      x = up[-2];
+	      x <<= GMP_NAIL_BITS;
+	      x >>= nbits;
+	      mlo |= x;
+	      nbits += GMP_NUMB_BITS;
+
+	      if (LIMBS_PER_DOUBLE >= 4 && nbits < 32 && size > 3)
+		{
+		  x = up[-3];
+		  x <<= GMP_NAIL_BITS;
+		  x >>= nbits;
+		  mlo |= x;
+		  nbits += GMP_NUMB_BITS;
+		}
+	    }
+	}
+
+    done:;
+
+#endif
+      if (UNLIKELY (exp >= CONST_1024))
+	{
+	  /* overflow, return infinity */
+	ieee_infinity:
+	  mhi = 0;
+	  mlo = 0;
+	  exp = 1024;
+	}
+      else if (UNLIKELY (exp <= CONST_NEG_1023))
+	{
+	  int rshift;
+
+	  if (LIKELY (exp <= CONST_NEG_1022_SUB_53))
+	    return 0.0;	 /* denorm underflows to zero */
+
+	  rshift = -1022 - exp;
+	  ASSERT (rshift > 0 && rshift < 53);
+#if GMP_LIMB_BITS > 53
+	  mlo >>= rshift;
+	  mhi = mlo >> 32;
+#else
+	  if (rshift >= 32)
+	    {
+	      mlo = mhi;
+	      mhi = 0;
+	      rshift -= 32;
+	    }
+	  lshift = GMP_LIMB_BITS - rshift;
+	  mlo = (mlo >> rshift) | (rshift == 0 ? 0 : mhi << lshift);
+	  mhi >>= rshift;
+#endif
+	  exp = -1023;
+	}
+      u.s.manh = mhi;
+      u.s.manl = mlo;
+      u.s.exp = exp + 1023;
+      u.s.sig = (sign < 0);
+      return u.d;
+    }
+#define FORMAT_RECOGNIZED 1
+#endif
+
+#if HAVE_DOUBLE_VAX_D
+    {
+      union double_extract u;
+
+      up += size;
+
+      mhi = up[-1];
+
+      count_leading_zeros (lshift, mhi);
+      exp -= lshift;
+      mhi <<= lshift;
+
+      mlo = 0;
+      if (size > 1)
+	{
+	  mlo = up[-2];
+	  if (lshift != 0)
+	    mhi += mlo >> (GMP_LIMB_BITS - lshift);
+	  mlo <<= lshift;
+
+	  if (size > 2 && lshift > 8)
+	    {
+	      x = up[-3];
+	      mlo += x >> (GMP_LIMB_BITS - lshift);
+	    }
+	}
+
+      if (UNLIKELY (exp >= 128))
+	{
+	  /* overflow, return maximum number */
+	  mhi = 0xffffffff;
+	  mlo = 0xffffffff;
+	  exp = 127;
+	}
+      else if (UNLIKELY (exp < -128))
+	{
+	  return 0.0;	 /* underflows to zero */
+	}
+
+      u.s.man3 = mhi >> 24;	/* drop msb, since implicit */
+      u.s.man2 = mhi >> 8;
+      u.s.man1 = (mhi << 8) + (mlo >> 24);
+      u.s.man0 = mlo >> 8;
+      u.s.exp = exp + 128;
+      u.s.sig = sign < 0;
+      return u.d;
+    }
+#define FORMAT_RECOGNIZED 1
+#endif
+
+#if ! FORMAT_RECOGNIZED
+
+#if !defined(GMP_DBL_MANT_BITS)
+#if defined(DBL_MANT_DIG) && FLT_RADIX == 2
+#define GMP_DBL_MANT_BITS DBL_MANT_DIG
+#else
+/* FIXME: Chose a smarter default value. */
+#define GMP_DBL_MANT_BITS (16 * sizeof (double))
+#endif
+#endif
+
+    { /* Non-IEEE or strange limb size, generically convert
+	 GMP_DBL_MANT_BITS bits. */
+      mp_limb_t l;
+      int m;
+      mp_size_t i;
+      double d, weight;
+      unsigned long uexp;
+
+      /* First generate an fp number disregarding exp, instead keeping things
+	 within the numb base factor from 1, which should prevent overflow and
+	 underflow even for the most exponent limited fp formats.  */
+      i = size - 1;
+      l = up[i];
+      count_leading_zeros (m, l);
+      m = m + GMP_DBL_MANT_BITS - GMP_LIMB_BITS;
+      if (m < 0)
+	l &= GMP_NUMB_MAX << -m;
+      d = l;
+      for (weight = 1/MP_BASE_AS_DOUBLE; m > 0 && --i >= 0;)
+	{
+	  l = up[i];
+	  m -= GMP_NUMB_BITS;
+	  if (m < 0)
+	    l &= GMP_NUMB_MAX << -m;
+	  d += l * weight;
+	  weight /= MP_BASE_AS_DOUBLE;
+	  if (weight == 0)
+	    break;
+	}
+
+      /* Now apply exp.  */
+      exp -= GMP_NUMB_BITS;
+      if (exp > 0)
+	{
+	  weight = 2.0;
+	  uexp = exp;
+	}
+      else
+	{
+	  weight = 0.5;
+	  uexp = NEG_CAST (unsigned long, exp);
+	}
+#if 1
+      /* Square-and-multiply exponentiation.  */
+      if (uexp & 1)
+	d *= weight;
+      while (uexp >>= 1)
+	{
+	  weight *= weight;
+	  if (uexp & 1)
+	    d *= weight;
+	}
+#else
+      /* Plain exponentiation.  */
+      while (uexp > 0)
+	{
+	  d *= weight;
+	  uexp--;
+	}
+#endif
+
+      return sign >= 0 ? d : -d;
+    }
+#endif
+}