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Re: [PATCH][ppc] Use generic mpa.c code for everything except __sqrand __mul


Ping!

On Thu, Feb 21, 2013 at 04:12:22PM +0530, Siddhesh Poyarekar wrote:
> Hi,
> 
> Here's a patch that applies on top of all the patches I've posted so
> far to make the powerpc mpa.c use much of the generic mpa.c,
> overriding only the __mul and __sqr functions since the powerpc
> implementation of those functions currrently need to be different.  I
> have compared the generated code using objdump to verify that the
> generated code does not change in powerpc due to this.  The only thing
> that changes is the order of function definition in the binary between
> __dvd and __sqr.
> 
> The intent of doing this is to ensure that only functions that are
> really necessary to be powerpc-only remain duplicated and everything
> else is common code.
> 
> Siddhesh
> 
> 	* sysdeps/ieee754/dbl-64/mpa.c [!NO__MUL]: Define __mul.
> 	[!NO__SQR]: Define __sqr.
> 	* sysdeps/powerpc/powerpc32/power4/fpu/mpa.c: define NO__MUL
> 	and NO__SQR.  Remove all code except __mul and __sqr.  Include
> 	sysdeps/ieee754/dbl-64/mpa.c.
> 	* sysdeps/powerpc/powerpc64/power4/fpu/mpa.c: Likewise.
> 
> diff --git a/sysdeps/ieee754/dbl-64/mpa.c b/sysdeps/ieee754/dbl-64/mpa.c
> index cad227a..c246c8c 100644
> --- a/sysdeps/ieee754/dbl-64/mpa.c
> +++ b/sysdeps/ieee754/dbl-64/mpa.c
> @@ -611,6 +611,7 @@ __sub (const mp_no *x, const mp_no *y, mp_no *z, int p)
>      }
>  }
>  
> +#ifndef NO__MUL
>  /* Multiply *X and *Y and store result in *Z.  X and Y may overlap but not X
>     and Z or Y and Z.  For P in [1, 2, 3], the exact result is truncated to P
>     digits.  In case P > 3 the error is bounded by 1.001 ULP.  */
> @@ -761,7 +762,9 @@ __mul (const mp_no *x, const mp_no *y, mp_no *z, int p)
>    EZ = e;
>    Z[0] = X[0] * Y[0];
>  }
> +#endif
>  
> +#ifndef NO__SQR
>  /* Square *X and store result in *Y.  X and Y may not overlap.  For P in
>     [1, 2, 3], the exact result is truncated to P digits.  In case P > 3 the
>     error is bounded by 1.001 ULP.  This is a faster special case of
> @@ -862,6 +865,7 @@ __sqr (const mp_no *x, mp_no *y, int p)
>  
>    EY = e;
>  }
> +#endif
>  
>  /* Invert *X and store in *Y.  Relative error bound:
>     - For P = 2: 1.001 * R ^ (1 - P)
> diff --git a/sysdeps/powerpc/powerpc32/power4/fpu/mpa.c b/sysdeps/powerpc/powerpc32/power4/fpu/mpa.c
> index b226647..ef7ada7 100644
> --- a/sysdeps/powerpc/powerpc32/power4/fpu/mpa.c
> +++ b/sysdeps/powerpc/powerpc32/power4/fpu/mpa.c
> @@ -17,582 +17,12 @@
>   * You should have received a copy of the GNU Lesser General Public License
>   * along with this program; if not, see <http://www.gnu.org/licenses/>.
>   */
> -/************************************************************************/
> -/*  MODULE_NAME: mpa.c                                                  */
> -/*                                                                      */
> -/*  FUNCTIONS:                                                          */
> -/*               mcr                                                    */
> -/*               acr                                                    */
> -/*               cpy                                                    */
> -/*               norm                                                   */
> -/*               denorm                                                 */
> -/*               mp_dbl                                                 */
> -/*               dbl_mp                                                 */
> -/*               add_magnitudes                                         */
> -/*               sub_magnitudes                                         */
> -/*               add                                                    */
> -/*               sub                                                    */
> -/*               mul                                                    */
> -/*               inv                                                    */
> -/*               dvd                                                    */
> -/*                                                                      */
> -/* Arithmetic functions for multiple precision numbers.                 */
> -/* Relative errors are bounded                                          */
> -/************************************************************************/
>  
> +/* Define __mul and __sqr and use the rest from generic code.  */
> +#define NO__MUL
> +#define NO__SQR
>  
> -#include "endian.h"
> -#include "mpa.h"
> -#include <sys/param.h>
> -
> -const mp_no mpone = {1, {1.0, 1.0}};
> -const mp_no mptwo = {1, {1.0, 2.0}};
> -
> -/* Compare mantissa of two multiple precision numbers regardless of the sign
> -   and exponent of the numbers.  */
> -static int
> -mcr (const mp_no *x, const mp_no *y, int p)
> -{
> -  long i;
> -  long p2 = p;
> -  for (i = 1; i <= p2; i++)
> -    {
> -      if (X[i] == Y[i])
> -	continue;
> -      else if (X[i] > Y[i])
> -	return 1;
> -      else
> -	return -1;
> -    }
> -  return 0;
> -}
> -
> -/* Compare the absolute values of two multiple precision numbers.  */
> -int
> -__acr (const mp_no *x, const mp_no *y, int p)
> -{
> -  long i;
> -
> -  if (X[0] == ZERO)
> -    {
> -      if (Y[0] == ZERO)
> -	i = 0;
> -      else
> -	i = -1;
> -    }
> -  else if (Y[0] == ZERO)
> -    i = 1;
> -  else
> -    {
> -      if (EX > EY)
> -	i = 1;
> -      else if (EX < EY)
> -	i = -1;
> -      else
> -	i = mcr (x, y, p);
> -    }
> -
> -  return i;
> -}
> -
> -/* Copy multiple precision number X into Y.  They could be the same
> -   number.  */
> -void
> -__cpy (const mp_no *x, mp_no *y, int p)
> -{
> -  long i;
> -
> -  EY = EX;
> -  for (i = 0; i <= p; i++)
> -    Y[i] = X[i];
> -}
> -
> -/* Convert a multiple precision number *X into a double precision
> -   number *Y, normalized case  (|x| >= 2**(-1022))).  */
> -static void
> -norm (const mp_no *x, double *y, int p)
> -{
> -#define R RADIXI
> -  long i;
> -  double a, c, u, v, z[5];
> -  if (p < 5)
> -    {
> -      if (p == 1)
> -	c = X[1];
> -      else if (p == 2)
> -	c = X[1] + R * X[2];
> -      else if (p == 3)
> -	c = X[1] + R * (X[2] + R * X[3]);
> -      else if (p == 4)
> -	c = (X[1] + R * X[2]) + R * R * (X[3] + R * X[4]);
> -    }
> -  else
> -    {
> -      for (a = ONE, z[1] = X[1]; z[1] < TWO23;)
> -	{
> -	  a *= TWO;
> -	  z[1] *= TWO;
> -	}
> -
> -      for (i = 2; i < 5; i++)
> -	{
> -	  z[i] = X[i] * a;
> -	  u = (z[i] + CUTTER) - CUTTER;
> -	  if (u > z[i])
> -	    u -= RADIX;
> -	  z[i] -= u;
> -	  z[i - 1] += u * RADIXI;
> -	}
> -
> -      u = (z[3] + TWO71) - TWO71;
> -      if (u > z[3])
> -	u -= TWO19;
> -      v = z[3] - u;
> -
> -      if (v == TWO18)
> -	{
> -	  if (z[4] == ZERO)
> -	    {
> -	      for (i = 5; i <= p; i++)
> -		{
> -		  if (X[i] == ZERO)
> -		    continue;
> -		  else
> -		    {
> -		      z[3] += ONE;
> -		      break;
> -		    }
> -		}
> -	    }
> -	  else
> -	    z[3] += ONE;
> -	}
> -
> -      c = (z[1] + R * (z[2] + R * z[3])) / a;
> -    }
> -
> -  c *= X[0];
> -
> -  for (i = 1; i < EX; i++)
> -    c *= RADIX;
> -  for (i = 1; i > EX; i--)
> -    c *= RADIXI;
> -
> -  *y = c;
> -#undef R
> -}
> -
> -/* Convert a multiple precision number *X into a double precision
> -   number *Y, Denormal case  (|x| < 2**(-1022))).  */
> -static void
> -denorm (const mp_no *x, double *y, int p)
> -{
> -  long i, k;
> -  long p2 = p;
> -  double c, u, z[5];
> -
> -#define R RADIXI
> -  if (EX < -44 || (EX == -44 && X[1] < TWO5))
> -    {
> -      *y = ZERO;
> -      return;
> -    }
> -
> -  if (p2 == 1)
> -    {
> -      if (EX == -42)
> -	{
> -	  z[1] = X[1] + TWO10;
> -	  z[2] = ZERO;
> -	  z[3] = ZERO;
> -	  k = 3;
> -	}
> -      else if (EX == -43)
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = X[1];
> -	  z[3] = ZERO;
> -	  k = 2;
> -	}
> -      else
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = ZERO;
> -	  z[3] = X[1];
> -	  k = 1;
> -	}
> -    }
> -  else if (p2 == 2)
> -    {
> -      if (EX == -42)
> -	{
> -	  z[1] = X[1] + TWO10;
> -	  z[2] = X[2];
> -	  z[3] = ZERO;
> -	  k = 3;
> -	}
> -      else if (EX == -43)
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = X[1];
> -	  z[3] = X[2];
> -	  k = 2;
> -	}
> -      else
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = ZERO;
> -	  z[3] = X[1];
> -	  k = 1;
> -	}
> -    }
> -  else
> -    {
> -      if (EX == -42)
> -	{
> -	  z[1] = X[1] + TWO10;
> -	  z[2] = X[2];
> -	  k = 3;
> -	}
> -      else if (EX == -43)
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = X[1];
> -	  k = 2;
> -	}
> -      else
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = ZERO;
> -	  k = 1;
> -	}
> -      z[3] = X[k];
> -    }
> -
> -  u = (z[3] + TWO57) - TWO57;
> -  if (u > z[3])
> -    u -= TWO5;
> -
> -  if (u == z[3])
> -    {
> -      for (i = k + 1; i <= p2; i++)
> -	{
> -	  if (X[i] == ZERO)
> -	    continue;
> -	  else
> -	    {
> -	      z[3] += ONE;
> -	      break;
> -	    }
> -	}
> -    }
> -
> -  c = X[0] * ((z[1] + R * (z[2] + R * z[3])) - TWO10);
> -
> -  *y = c * TWOM1032;
> -#undef R
> -}
> -
> -/* Convert multiple precision number *X into double precision number *Y.  The
> -   result is correctly rounded to the nearest/even.  */
> -void
> -__mp_dbl (const mp_no *x, double *y, int p)
> -{
> -  if (X[0] == ZERO)
> -    {
> -      *y = ZERO;
> -      return;
> -    }
> -
> -  if (__glibc_likely (EX > -42 || (EX == -42 && X[1] >= TWO10)))
> -    norm (x, y, p);
> -  else
> -    denorm (x, y, p);
> -}
> -
> -/* Get the multiple precision equivalent of X into *Y.  If the precision is too
> -   small, the result is truncated.  */
> -void
> -__dbl_mp (double x, mp_no *y, int p)
> -{
> -  long i, n;
> -  long p2 = p;
> -  double u;
> -
> -  /* Sign.  */
> -  if (x == ZERO)
> -    {
> -      Y[0] = ZERO;
> -      return;
> -    }
> -  else if (x > ZERO)
> -    Y[0] = ONE;
> -  else
> -    {
> -      Y[0] = MONE;
> -      x = -x;
> -    }
> -
> -  /* Exponent.  */
> -  for (EY = ONE; x >= RADIX; EY += ONE)
> -    x *= RADIXI;
> -  for (; x < ONE; EY -= ONE)
> -    x *= RADIX;
> -
> -  /* Digits.  */
> -  n = MIN (p2, 4);
> -  for (i = 1; i <= n; i++)
> -    {
> -      u = (x + TWO52) - TWO52;
> -      if (u > x)
> -	u -= ONE;
> -      Y[i] = u;
> -      x -= u;
> -      x *= RADIX;
> -    }
> -  for (; i <= p2; i++)
> -    Y[i] = ZERO;
> -}
> -
> -/* Add magnitudes of *X and *Y assuming that abs (*X) >= abs (*Y) > 0.  The
> -   sign of the sum *Z is not changed.  X and Y may overlap but not X and Z or
> -   Y and Z.  No guard digit is used.  The result equals the exact sum,
> -   truncated.  */
> -static void
> -add_magnitudes (const mp_no *x, const mp_no *y, mp_no *z, int p)
> -{
> -  long i, j, k;
> -  long p2 = p;
> -  double zk;
> -
> -  EZ = EX;
> -
> -  i = p2;
> -  j = p2 + EY - EX;
> -  k = p2 + 1;
> -
> -  if (__glibc_unlikely (j < 1))
> -    {
> -      __cpy (x, z, p);
> -      return;
> -    }
> -
> -  zk = ZERO;
> -
> -  for (; j > 0; i--, j--)
> -    {
> -      zk += X[i] + Y[j];
> -      if (zk >= RADIX)
> -	{
> -	  Z[k--] = zk - RADIX;
> -	  zk = ONE;
> -	}
> -      else
> -        {
> -	  Z[k--] = zk;
> -	  zk = ZERO;
> -	}
> -    }
> -
> -  for (; i > 0; i--)
> -    {
> -      zk += X[i];
> -      if (zk >= RADIX)
> -	{
> -	  Z[k--] = zk - RADIX;
> -	  zk = ONE;
> -	}
> -      else
> -        {
> -	  Z[k--] = zk;
> -	  zk = ZERO;
> -	}
> -    }
> -
> -  if (zk == ZERO)
> -    {
> -      for (i = 1; i <= p2; i++)
> -	Z[i] = Z[i + 1];
> -    }
> -  else
> -    {
> -      Z[1] = zk;
> -      EZ += ONE;
> -    }
> -}
> -
> -/* Subtract the magnitudes of *X and *Y assuming that abs (*x) > abs (*y) > 0.
> -   The sign of the difference *Z is not changed.  X and Y may overlap but not X
> -   and Z or Y and Z.  One guard digit is used.  The error is less than one
> -   ULP.  */
> -static void
> -sub_magnitudes (const mp_no *x, const mp_no *y, mp_no *z, int p)
> -{
> -  long i, j, k;
> -  long p2 = p;
> -  double zk;
> -
> -  EZ = EX;
> -  i = p2;
> -  j = p2 + EY - EX;
> -  k = p2;
> -
> -  /* Y is too small compared to X, copy X over to the result.  */
> -  if (__glibc_unlikely (j < 1))
> -    {
> -      __cpy (x, z, p);
> -      return;
> -    }
> -
> -  /* The relevant least significant digit in Y is non-zero, so we factor it in
> -     to enhance accuracy.  */
> -  if (j < p2 && Y[j + 1] > ZERO)
> -    {
> -      Z[k + 1] = RADIX - Y[j + 1];
> -      zk = MONE;
> -    }
> -  else
> -    zk = Z[k + 1] = ZERO;
> -
> -  /* Subtract and borrow.  */
> -  for (; j > 0; i--, j--)
> -    {
> -      zk += (X[i] - Y[j]);
> -      if (zk < ZERO)
> -	{
> -	  Z[k--] = zk + RADIX;
> -	  zk = MONE;
> -	}
> -      else
> -        {
> -	  Z[k--] = zk;
> -	  zk = ZERO;
> -	}
> -    }
> -
> -  /* We're done with digits from Y, so it's just digits in X.  */
> -  for (; i > 0; i--)
> -    {
> -      zk += X[i];
> -      if (zk < ZERO)
> -	{
> -	  Z[k--] = zk + RADIX;
> -	  zk = MONE;
> -	}
> -      else
> -        {
> -	  Z[k--] = zk;
> -	  zk = ZERO;
> -	}
> -    }
> -
> -  /* Normalize.  */
> -  for (i = 1; Z[i] == ZERO; i++);
> -  EZ = EZ - i + 1;
> -  for (k = 1; i <= p2 + 1;)
> -    Z[k++] = Z[i++];
> -  for (; k <= p2;)
> -    Z[k++] = ZERO;
> -}
> -
> -/* Add *X and *Y and store the result in *Z.  X and Y may overlap, but not X
> -   and Z or Y and Z.  One guard digit is used.  The error is less than one
> -   ULP.  */
> -void
> -__add (const mp_no *x, const mp_no *y, mp_no *z, int p)
> -{
> -  int n;
> -
> -  if (X[0] == ZERO)
> -    {
> -      __cpy (y, z, p);
> -      return;
> -    }
> -  else if (Y[0] == ZERO)
> -    {
> -      __cpy (x, z, p);
> -      return;
> -    }
> -
> -  if (X[0] == Y[0])
> -    {
> -      if (__acr (x, y, p) > 0)
> -	{
> -	  add_magnitudes (x, y, z, p);
> -	  Z[0] = X[0];
> -	}
> -      else
> -	{
> -	  add_magnitudes (y, x, z, p);
> -	  Z[0] = Y[0];
> -	}
> -    }
> -  else
> -    {
> -      if ((n = __acr (x, y, p)) == 1)
> -	{
> -	  sub_magnitudes (x, y, z, p);
> -	  Z[0] = X[0];
> -	}
> -      else if (n == -1)
> -	{
> -	  sub_magnitudes (y, x, z, p);
> -	  Z[0] = Y[0];
> -	}
> -      else
> -	Z[0] = ZERO;
> -    }
> -}
> -
> -/* Subtract *Y from *X and return the result in *Z.  X and Y may overlap but
> -   not X and Z or Y and Z.  One guard digit is used.  The error is less than
> -   one ULP.  */
> -void
> -__sub (const mp_no *x, const mp_no *y, mp_no *z, int p)
> -{
> -  int n;
> -
> -  if (X[0] == ZERO)
> -    {
> -      __cpy (y, z, p);
> -      Z[0] = -Z[0];
> -      return;
> -    }
> -  else if (Y[0] == ZERO)
> -    {
> -      __cpy (x, z, p);
> -      return;
> -    }
> -
> -  if (X[0] != Y[0])
> -    {
> -      if (__acr (x, y, p) > 0)
> -	{
> -	  add_magnitudes (x, y, z, p);
> -	  Z[0] = X[0];
> -	}
> -      else
> -	{
> -	  add_magnitudes (y, x, z, p);
> -	  Z[0] = -Y[0];
> -	}
> -    }
> -  else
> -    {
> -      if ((n = __acr (x, y, p)) == 1)
> -	{
> -	  sub_magnitudes (x, y, z, p);
> -	  Z[0] = X[0];
> -	}
> -      else if (n == -1)
> -	{
> -	  sub_magnitudes (y, x, z, p);
> -	  Z[0] = -Y[0];
> -	}
> -      else
> -	Z[0] = ZERO;
> -    }
> -}
> +#include <sysdeps/ieee754/dbl-64/mpa.c>
>  
>  /* Multiply *X and *Y and store result in *Z.  X and Y may overlap but not X
>     and Z or Y and Z.  For P in [1, 2, 3], the exact result is truncated to P
> @@ -781,57 +211,3 @@ __sqr (const mp_no *x, mp_no *y, int p)
>        EY--;
>      }
>  }
> -
> -/* Invert *X and store in *Y.  Relative error bound:
> -   - For P = 2: 1.001 * R ^ (1 - P)
> -   - For P = 3: 1.063 * R ^ (1 - P)
> -   - For P > 3: 2.001 * R ^ (1 - P)
> -
> -   *X = 0 is not permissible.  */
> -static void
> -__inv (const mp_no *x, mp_no *y, int p)
> -{
> -  long i;
> -  double t;
> -  mp_no z, w;
> -  static const int np1[] =
> -    { 0, 0, 0, 0, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3,
> -    4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4
> -  };
> -
> -  __cpy (x, &z, p);
> -  z.e = 0;
> -  __mp_dbl (&z, &t, p);
> -  t = ONE / t;
> -  __dbl_mp (t, y, p);
> -  EY -= EX;
> -
> -  for (i = 0; i < np1[p]; i++)
> -    {
> -      __cpy (y, &w, p);
> -      __mul (x, &w, y, p);
> -      __sub (&mptwo, y, &z, p);
> -      __mul (&w, &z, y, p);
> -    }
> -}
> -
> -/* Divide *X by *Y and store result in *Z.  X and Y may overlap but not X and Z
> -   or Y and Z.  Relative error bound:
> -   - For P = 2: 2.001 * R ^ (1 - P)
> -   - For P = 3: 2.063 * R ^ (1 - P)
> -   - For P > 3: 3.001 * R ^ (1 - P)
> -
> -   *X = 0 is not permissible.  */
> -void
> -__dvd (const mp_no *x, const mp_no *y, mp_no *z, int p)
> -{
> -  mp_no w;
> -
> -  if (X[0] == ZERO)
> -    Z[0] = ZERO;
> -  else
> -    {
> -      __inv (y, &w, p);
> -      __mul (x, &w, z, p);
> -    }
> -}
> diff --git a/sysdeps/powerpc/powerpc64/power4/fpu/mpa.c b/sysdeps/powerpc/powerpc64/power4/fpu/mpa.c
> index b226647..ef7ada7 100644
> --- a/sysdeps/powerpc/powerpc64/power4/fpu/mpa.c
> +++ b/sysdeps/powerpc/powerpc64/power4/fpu/mpa.c
> @@ -17,582 +17,12 @@
>   * You should have received a copy of the GNU Lesser General Public License
>   * along with this program; if not, see <http://www.gnu.org/licenses/>.
>   */
> -/************************************************************************/
> -/*  MODULE_NAME: mpa.c                                                  */
> -/*                                                                      */
> -/*  FUNCTIONS:                                                          */
> -/*               mcr                                                    */
> -/*               acr                                                    */
> -/*               cpy                                                    */
> -/*               norm                                                   */
> -/*               denorm                                                 */
> -/*               mp_dbl                                                 */
> -/*               dbl_mp                                                 */
> -/*               add_magnitudes                                         */
> -/*               sub_magnitudes                                         */
> -/*               add                                                    */
> -/*               sub                                                    */
> -/*               mul                                                    */
> -/*               inv                                                    */
> -/*               dvd                                                    */
> -/*                                                                      */
> -/* Arithmetic functions for multiple precision numbers.                 */
> -/* Relative errors are bounded                                          */
> -/************************************************************************/
>  
> +/* Define __mul and __sqr and use the rest from generic code.  */
> +#define NO__MUL
> +#define NO__SQR
>  
> -#include "endian.h"
> -#include "mpa.h"
> -#include <sys/param.h>
> -
> -const mp_no mpone = {1, {1.0, 1.0}};
> -const mp_no mptwo = {1, {1.0, 2.0}};
> -
> -/* Compare mantissa of two multiple precision numbers regardless of the sign
> -   and exponent of the numbers.  */
> -static int
> -mcr (const mp_no *x, const mp_no *y, int p)
> -{
> -  long i;
> -  long p2 = p;
> -  for (i = 1; i <= p2; i++)
> -    {
> -      if (X[i] == Y[i])
> -	continue;
> -      else if (X[i] > Y[i])
> -	return 1;
> -      else
> -	return -1;
> -    }
> -  return 0;
> -}
> -
> -/* Compare the absolute values of two multiple precision numbers.  */
> -int
> -__acr (const mp_no *x, const mp_no *y, int p)
> -{
> -  long i;
> -
> -  if (X[0] == ZERO)
> -    {
> -      if (Y[0] == ZERO)
> -	i = 0;
> -      else
> -	i = -1;
> -    }
> -  else if (Y[0] == ZERO)
> -    i = 1;
> -  else
> -    {
> -      if (EX > EY)
> -	i = 1;
> -      else if (EX < EY)
> -	i = -1;
> -      else
> -	i = mcr (x, y, p);
> -    }
> -
> -  return i;
> -}
> -
> -/* Copy multiple precision number X into Y.  They could be the same
> -   number.  */
> -void
> -__cpy (const mp_no *x, mp_no *y, int p)
> -{
> -  long i;
> -
> -  EY = EX;
> -  for (i = 0; i <= p; i++)
> -    Y[i] = X[i];
> -}
> -
> -/* Convert a multiple precision number *X into a double precision
> -   number *Y, normalized case  (|x| >= 2**(-1022))).  */
> -static void
> -norm (const mp_no *x, double *y, int p)
> -{
> -#define R RADIXI
> -  long i;
> -  double a, c, u, v, z[5];
> -  if (p < 5)
> -    {
> -      if (p == 1)
> -	c = X[1];
> -      else if (p == 2)
> -	c = X[1] + R * X[2];
> -      else if (p == 3)
> -	c = X[1] + R * (X[2] + R * X[3]);
> -      else if (p == 4)
> -	c = (X[1] + R * X[2]) + R * R * (X[3] + R * X[4]);
> -    }
> -  else
> -    {
> -      for (a = ONE, z[1] = X[1]; z[1] < TWO23;)
> -	{
> -	  a *= TWO;
> -	  z[1] *= TWO;
> -	}
> -
> -      for (i = 2; i < 5; i++)
> -	{
> -	  z[i] = X[i] * a;
> -	  u = (z[i] + CUTTER) - CUTTER;
> -	  if (u > z[i])
> -	    u -= RADIX;
> -	  z[i] -= u;
> -	  z[i - 1] += u * RADIXI;
> -	}
> -
> -      u = (z[3] + TWO71) - TWO71;
> -      if (u > z[3])
> -	u -= TWO19;
> -      v = z[3] - u;
> -
> -      if (v == TWO18)
> -	{
> -	  if (z[4] == ZERO)
> -	    {
> -	      for (i = 5; i <= p; i++)
> -		{
> -		  if (X[i] == ZERO)
> -		    continue;
> -		  else
> -		    {
> -		      z[3] += ONE;
> -		      break;
> -		    }
> -		}
> -	    }
> -	  else
> -	    z[3] += ONE;
> -	}
> -
> -      c = (z[1] + R * (z[2] + R * z[3])) / a;
> -    }
> -
> -  c *= X[0];
> -
> -  for (i = 1; i < EX; i++)
> -    c *= RADIX;
> -  for (i = 1; i > EX; i--)
> -    c *= RADIXI;
> -
> -  *y = c;
> -#undef R
> -}
> -
> -/* Convert a multiple precision number *X into a double precision
> -   number *Y, Denormal case  (|x| < 2**(-1022))).  */
> -static void
> -denorm (const mp_no *x, double *y, int p)
> -{
> -  long i, k;
> -  long p2 = p;
> -  double c, u, z[5];
> -
> -#define R RADIXI
> -  if (EX < -44 || (EX == -44 && X[1] < TWO5))
> -    {
> -      *y = ZERO;
> -      return;
> -    }
> -
> -  if (p2 == 1)
> -    {
> -      if (EX == -42)
> -	{
> -	  z[1] = X[1] + TWO10;
> -	  z[2] = ZERO;
> -	  z[3] = ZERO;
> -	  k = 3;
> -	}
> -      else if (EX == -43)
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = X[1];
> -	  z[3] = ZERO;
> -	  k = 2;
> -	}
> -      else
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = ZERO;
> -	  z[3] = X[1];
> -	  k = 1;
> -	}
> -    }
> -  else if (p2 == 2)
> -    {
> -      if (EX == -42)
> -	{
> -	  z[1] = X[1] + TWO10;
> -	  z[2] = X[2];
> -	  z[3] = ZERO;
> -	  k = 3;
> -	}
> -      else if (EX == -43)
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = X[1];
> -	  z[3] = X[2];
> -	  k = 2;
> -	}
> -      else
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = ZERO;
> -	  z[3] = X[1];
> -	  k = 1;
> -	}
> -    }
> -  else
> -    {
> -      if (EX == -42)
> -	{
> -	  z[1] = X[1] + TWO10;
> -	  z[2] = X[2];
> -	  k = 3;
> -	}
> -      else if (EX == -43)
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = X[1];
> -	  k = 2;
> -	}
> -      else
> -	{
> -	  z[1] = TWO10;
> -	  z[2] = ZERO;
> -	  k = 1;
> -	}
> -      z[3] = X[k];
> -    }
> -
> -  u = (z[3] + TWO57) - TWO57;
> -  if (u > z[3])
> -    u -= TWO5;
> -
> -  if (u == z[3])
> -    {
> -      for (i = k + 1; i <= p2; i++)
> -	{
> -	  if (X[i] == ZERO)
> -	    continue;
> -	  else
> -	    {
> -	      z[3] += ONE;
> -	      break;
> -	    }
> -	}
> -    }
> -
> -  c = X[0] * ((z[1] + R * (z[2] + R * z[3])) - TWO10);
> -
> -  *y = c * TWOM1032;
> -#undef R
> -}
> -
> -/* Convert multiple precision number *X into double precision number *Y.  The
> -   result is correctly rounded to the nearest/even.  */
> -void
> -__mp_dbl (const mp_no *x, double *y, int p)
> -{
> -  if (X[0] == ZERO)
> -    {
> -      *y = ZERO;
> -      return;
> -    }
> -
> -  if (__glibc_likely (EX > -42 || (EX == -42 && X[1] >= TWO10)))
> -    norm (x, y, p);
> -  else
> -    denorm (x, y, p);
> -}
> -
> -/* Get the multiple precision equivalent of X into *Y.  If the precision is too
> -   small, the result is truncated.  */
> -void
> -__dbl_mp (double x, mp_no *y, int p)
> -{
> -  long i, n;
> -  long p2 = p;
> -  double u;
> -
> -  /* Sign.  */
> -  if (x == ZERO)
> -    {
> -      Y[0] = ZERO;
> -      return;
> -    }
> -  else if (x > ZERO)
> -    Y[0] = ONE;
> -  else
> -    {
> -      Y[0] = MONE;
> -      x = -x;
> -    }
> -
> -  /* Exponent.  */
> -  for (EY = ONE; x >= RADIX; EY += ONE)
> -    x *= RADIXI;
> -  for (; x < ONE; EY -= ONE)
> -    x *= RADIX;
> -
> -  /* Digits.  */
> -  n = MIN (p2, 4);
> -  for (i = 1; i <= n; i++)
> -    {
> -      u = (x + TWO52) - TWO52;
> -      if (u > x)
> -	u -= ONE;
> -      Y[i] = u;
> -      x -= u;
> -      x *= RADIX;
> -    }
> -  for (; i <= p2; i++)
> -    Y[i] = ZERO;
> -}
> -
> -/* Add magnitudes of *X and *Y assuming that abs (*X) >= abs (*Y) > 0.  The
> -   sign of the sum *Z is not changed.  X and Y may overlap but not X and Z or
> -   Y and Z.  No guard digit is used.  The result equals the exact sum,
> -   truncated.  */
> -static void
> -add_magnitudes (const mp_no *x, const mp_no *y, mp_no *z, int p)
> -{
> -  long i, j, k;
> -  long p2 = p;
> -  double zk;
> -
> -  EZ = EX;
> -
> -  i = p2;
> -  j = p2 + EY - EX;
> -  k = p2 + 1;
> -
> -  if (__glibc_unlikely (j < 1))
> -    {
> -      __cpy (x, z, p);
> -      return;
> -    }
> -
> -  zk = ZERO;
> -
> -  for (; j > 0; i--, j--)
> -    {
> -      zk += X[i] + Y[j];
> -      if (zk >= RADIX)
> -	{
> -	  Z[k--] = zk - RADIX;
> -	  zk = ONE;
> -	}
> -      else
> -        {
> -	  Z[k--] = zk;
> -	  zk = ZERO;
> -	}
> -    }
> -
> -  for (; i > 0; i--)
> -    {
> -      zk += X[i];
> -      if (zk >= RADIX)
> -	{
> -	  Z[k--] = zk - RADIX;
> -	  zk = ONE;
> -	}
> -      else
> -        {
> -	  Z[k--] = zk;
> -	  zk = ZERO;
> -	}
> -    }
> -
> -  if (zk == ZERO)
> -    {
> -      for (i = 1; i <= p2; i++)
> -	Z[i] = Z[i + 1];
> -    }
> -  else
> -    {
> -      Z[1] = zk;
> -      EZ += ONE;
> -    }
> -}
> -
> -/* Subtract the magnitudes of *X and *Y assuming that abs (*x) > abs (*y) > 0.
> -   The sign of the difference *Z is not changed.  X and Y may overlap but not X
> -   and Z or Y and Z.  One guard digit is used.  The error is less than one
> -   ULP.  */
> -static void
> -sub_magnitudes (const mp_no *x, const mp_no *y, mp_no *z, int p)
> -{
> -  long i, j, k;
> -  long p2 = p;
> -  double zk;
> -
> -  EZ = EX;
> -  i = p2;
> -  j = p2 + EY - EX;
> -  k = p2;
> -
> -  /* Y is too small compared to X, copy X over to the result.  */
> -  if (__glibc_unlikely (j < 1))
> -    {
> -      __cpy (x, z, p);
> -      return;
> -    }
> -
> -  /* The relevant least significant digit in Y is non-zero, so we factor it in
> -     to enhance accuracy.  */
> -  if (j < p2 && Y[j + 1] > ZERO)
> -    {
> -      Z[k + 1] = RADIX - Y[j + 1];
> -      zk = MONE;
> -    }
> -  else
> -    zk = Z[k + 1] = ZERO;
> -
> -  /* Subtract and borrow.  */
> -  for (; j > 0; i--, j--)
> -    {
> -      zk += (X[i] - Y[j]);
> -      if (zk < ZERO)
> -	{
> -	  Z[k--] = zk + RADIX;
> -	  zk = MONE;
> -	}
> -      else
> -        {
> -	  Z[k--] = zk;
> -	  zk = ZERO;
> -	}
> -    }
> -
> -  /* We're done with digits from Y, so it's just digits in X.  */
> -  for (; i > 0; i--)
> -    {
> -      zk += X[i];
> -      if (zk < ZERO)
> -	{
> -	  Z[k--] = zk + RADIX;
> -	  zk = MONE;
> -	}
> -      else
> -        {
> -	  Z[k--] = zk;
> -	  zk = ZERO;
> -	}
> -    }
> -
> -  /* Normalize.  */
> -  for (i = 1; Z[i] == ZERO; i++);
> -  EZ = EZ - i + 1;
> -  for (k = 1; i <= p2 + 1;)
> -    Z[k++] = Z[i++];
> -  for (; k <= p2;)
> -    Z[k++] = ZERO;
> -}
> -
> -/* Add *X and *Y and store the result in *Z.  X and Y may overlap, but not X
> -   and Z or Y and Z.  One guard digit is used.  The error is less than one
> -   ULP.  */
> -void
> -__add (const mp_no *x, const mp_no *y, mp_no *z, int p)
> -{
> -  int n;
> -
> -  if (X[0] == ZERO)
> -    {
> -      __cpy (y, z, p);
> -      return;
> -    }
> -  else if (Y[0] == ZERO)
> -    {
> -      __cpy (x, z, p);
> -      return;
> -    }
> -
> -  if (X[0] == Y[0])
> -    {
> -      if (__acr (x, y, p) > 0)
> -	{
> -	  add_magnitudes (x, y, z, p);
> -	  Z[0] = X[0];
> -	}
> -      else
> -	{
> -	  add_magnitudes (y, x, z, p);
> -	  Z[0] = Y[0];
> -	}
> -    }
> -  else
> -    {
> -      if ((n = __acr (x, y, p)) == 1)
> -	{
> -	  sub_magnitudes (x, y, z, p);
> -	  Z[0] = X[0];
> -	}
> -      else if (n == -1)
> -	{
> -	  sub_magnitudes (y, x, z, p);
> -	  Z[0] = Y[0];
> -	}
> -      else
> -	Z[0] = ZERO;
> -    }
> -}
> -
> -/* Subtract *Y from *X and return the result in *Z.  X and Y may overlap but
> -   not X and Z or Y and Z.  One guard digit is used.  The error is less than
> -   one ULP.  */
> -void
> -__sub (const mp_no *x, const mp_no *y, mp_no *z, int p)
> -{
> -  int n;
> -
> -  if (X[0] == ZERO)
> -    {
> -      __cpy (y, z, p);
> -      Z[0] = -Z[0];
> -      return;
> -    }
> -  else if (Y[0] == ZERO)
> -    {
> -      __cpy (x, z, p);
> -      return;
> -    }
> -
> -  if (X[0] != Y[0])
> -    {
> -      if (__acr (x, y, p) > 0)
> -	{
> -	  add_magnitudes (x, y, z, p);
> -	  Z[0] = X[0];
> -	}
> -      else
> -	{
> -	  add_magnitudes (y, x, z, p);
> -	  Z[0] = -Y[0];
> -	}
> -    }
> -  else
> -    {
> -      if ((n = __acr (x, y, p)) == 1)
> -	{
> -	  sub_magnitudes (x, y, z, p);
> -	  Z[0] = X[0];
> -	}
> -      else if (n == -1)
> -	{
> -	  sub_magnitudes (y, x, z, p);
> -	  Z[0] = -Y[0];
> -	}
> -      else
> -	Z[0] = ZERO;
> -    }
> -}
> +#include <sysdeps/ieee754/dbl-64/mpa.c>
>  
>  /* Multiply *X and *Y and store result in *Z.  X and Y may overlap but not X
>     and Z or Y and Z.  For P in [1, 2, 3], the exact result is truncated to P
> @@ -781,57 +211,3 @@ __sqr (const mp_no *x, mp_no *y, int p)
>        EY--;
>      }
>  }
> -
> -/* Invert *X and store in *Y.  Relative error bound:
> -   - For P = 2: 1.001 * R ^ (1 - P)
> -   - For P = 3: 1.063 * R ^ (1 - P)
> -   - For P > 3: 2.001 * R ^ (1 - P)
> -
> -   *X = 0 is not permissible.  */
> -static void
> -__inv (const mp_no *x, mp_no *y, int p)
> -{
> -  long i;
> -  double t;
> -  mp_no z, w;
> -  static const int np1[] =
> -    { 0, 0, 0, 0, 1, 2, 2, 2, 2, 3, 3, 3, 3, 3, 3, 3, 3, 3,
> -    4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4, 4
> -  };
> -
> -  __cpy (x, &z, p);
> -  z.e = 0;
> -  __mp_dbl (&z, &t, p);
> -  t = ONE / t;
> -  __dbl_mp (t, y, p);
> -  EY -= EX;
> -
> -  for (i = 0; i < np1[p]; i++)
> -    {
> -      __cpy (y, &w, p);
> -      __mul (x, &w, y, p);
> -      __sub (&mptwo, y, &z, p);
> -      __mul (&w, &z, y, p);
> -    }
> -}
> -
> -/* Divide *X by *Y and store result in *Z.  X and Y may overlap but not X and Z
> -   or Y and Z.  Relative error bound:
> -   - For P = 2: 2.001 * R ^ (1 - P)
> -   - For P = 3: 2.063 * R ^ (1 - P)
> -   - For P > 3: 3.001 * R ^ (1 - P)
> -
> -   *X = 0 is not permissible.  */
> -void
> -__dvd (const mp_no *x, const mp_no *y, mp_no *z, int p)
> -{
> -  mp_no w;
> -
> -  if (X[0] == ZERO)
> -    Z[0] = ZERO;
> -  else
> -    {
> -      __inv (y, &w, p);
> -      __mul (x, &w, z, p);
> -    }
> -}


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