/* mpz_add, mpz_sub -- add or subtract integers.

Copyright 1991, 1993, 1994, 1996, 2000, 2001, 2011, 2012, 2020 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 "gmp-impl.h"

#ifdef OPERATION_add

#define FUNCTION     mpz_add

#define VARIATION

#endif

#ifdef OPERATION_sub

#define FUNCTION     mpz_sub

#define VARIATION    -

#endif

#ifndef FUNCTION

Error, need OPERATION_add or OPERATION_sub

#endif

void

FUNCTION (mpz_ptr w, mpz_srcptr u, mpz_srcptr v)

{

  mp_srcptr up, vp;

  mp_ptr wp;

  mp_size_t usize, vsize, wsize;

  mp_size_t abs_usize;

  mp_size_t abs_vsize;

  usize = SIZ(u);

  vsize = VARIATION SIZ(v);

  abs_usize = ABS (usize);

  abs_vsize = ABS (vsize);

  if (abs_usize < abs_vsize)

    {

      /* Swap U and V. */

      MPZ_SRCPTR_SWAP (u, v);

      MP_SIZE_T_SWAP (usize, vsize);

      MP_SIZE_T_SWAP (abs_usize, abs_vsize);

    }

  /* True: ABS_USIZE >= ABS_VSIZE.  */

  /* If not space for w (and possible carry), increase space.  */

  wsize = abs_usize + 1;

  wp = MPZ_REALLOC (w, wsize);

  /* These must be after realloc (u or v may be the same as w).  */

  up = PTR(u);

  vp = PTR(v);

  if ((usize ^ vsize) < 0)

    {

      /* U and V have different sign.  Need to compare them to determine

   which operand to subtract from which.  */

      /* This test is right since ABS_USIZE >= ABS_VSIZE.  */

      if (abs_usize != abs_vsize)

  {

    mpn_sub (wp, up, abs_usize, vp, abs_vsize);

    wsize = abs_usize;

    MPN_NORMALIZE_NOT_ZERO (wp, wsize);

    if (usize < 0)

      wsize = -wsize;

  }

      else

  {

    int cmp = mpn_cmp (up, vp, abs_usize);

    if (cmp < 0)

      {

        mpn_sub_n (wp, vp, up, abs_usize);

        wsize = abs_usize;

        MPN_NORMALIZE_NOT_ZERO (wp, wsize);

        if (usize >= 0)

    wsize = -wsize;

      }

    else if (cmp > 0)

      {

        mpn_sub_n (wp, up, vp, abs_usize);

        wsize = abs_usize;

        MPN_NORMALIZE_NOT_ZERO (wp, wsize);

        if (usize < 0)

    wsize = -wsize;

      }

    else

      wsize = 0;

  }

    }

  else

    {

      /* U and V have same sign.  Add them.  */

      mp_limb_t cy_limb = mpn_add (wp, up, abs_usize, vp, abs_vsize);

      wp[abs_usize] = cy_limb;

      wsize = abs_usize + cy_limb;

      if (usize < 0)

  wsize = -wsize;

    }

  SIZ(w) = wsize;

}

__gmpz_add

Line

Count

Source

51

574

{

52

574

  mp_srcptr up, vp;

53

574

  mp_ptr wp;

54

574

  mp_size_t usize, vsize, wsize;

55

574

  mp_size_t abs_usize;

56

574

  mp_size_t abs_vsize;

57

58

574

  usize = SIZ(u);

59

574

  vsize = VARIATION SIZ(v);

60

574

  abs_usize = ABS (usize);

61

574

  abs_vsize = ABS (vsize);

62

63

574

  if (abs_usize < abs_vsize)

64

96

    {

65

      /* Swap U and V. */

66

96

      MPZ_SRCPTR_SWAP (u, v);

67

96

      MP_SIZE_T_SWAP (usize, vsize);

68

96

      MP_SIZE_T_SWAP (abs_usize, abs_vsize);

69

96

    }

70

71

  /* True: ABS_USIZE >= ABS_VSIZE.  */

72

73

  /* If not space for w (and possible carry), increase space.  */

74

574

  wsize = abs_usize + 1;

75

574

  wp = MPZ_REALLOC (w, wsize);

76

77

  /* These must be after realloc (u or v may be the same as w).  */

78

574

  up = PTR(u);

79

574

  vp = PTR(v);

80

81

574

  if ((usize ^ vsize) < 0)

82

2

    {

83

      /* U and V have different sign.  Need to compare them to determine

84

   which operand to subtract from which.  */

85

86

      /* This test is right since ABS_USIZE >= ABS_VSIZE.  */

87

2

      if (abs_usize != abs_vsize)

88

2

  {

89

2

    mpn_sub (wp, up, abs_usize, vp, abs_vsize);

90

2

    wsize = abs_usize;

91

2

    MPN_NORMALIZE_NOT_ZERO (wp, wsize);

92

2

    if (usize < 0)

93

0

      wsize = -wsize;

94

2

  }

95

0

      else

96

0

  {

97

0

    int cmp = mpn_cmp (up, vp, abs_usize);

98

0

    if (cmp < 0)

99

0

      {

100

0

        mpn_sub_n (wp, vp, up, abs_usize);

101

0

        wsize = abs_usize;

102

0

        MPN_NORMALIZE_NOT_ZERO (wp, wsize);

103

0

        if (usize >= 0)

104

0

    wsize = -wsize;

105

0

      }

106

0

    else if (cmp > 0)

107

0

      {

108

0

        mpn_sub_n (wp, up, vp, abs_usize);

109

0

        wsize = abs_usize;

110

0

        MPN_NORMALIZE_NOT_ZERO (wp, wsize);

111

0

        if (usize < 0)

112

0

    wsize = -wsize;

113

0

      }

114

0

    else

115

0

      wsize = 0;

116

0

  }

117

2

    }

118

572

  else

119

572

    {

120

      /* U and V have same sign.  Add them.  */

121

572

      mp_limb_t cy_limb = mpn_add (wp, up, abs_usize, vp, abs_vsize);

122

572

      wp[abs_usize] = cy_limb;

123

572

      wsize = abs_usize + cy_limb;

124

572

      if (usize < 0)

125

0

  wsize = -wsize;

126

572

    }

127

128

574

  SIZ(w) = wsize;

129

574

}

Unexecuted instantiation: __gmpz_sub