1 | /* Copyright (C) 1992-2019 Free Software Foundation, Inc. |
---|---|

2 | This file is part of the GNU C Library. |

3 | |

4 | The GNU C Library is free software; you can redistribute it and/or |

5 | modify it under the terms of the GNU Lesser General Public |

6 | License as published by the Free Software Foundation; either |

7 | version 2.1 of the License, or (at your option) any later version. |

8 | |

9 | The GNU C Library is distributed in the hope that it will be useful, |

10 | but WITHOUT ANY WARRANTY; without even the implied warranty of |

11 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU |

12 | Lesser General Public License for more details. |

13 | |

14 | You should have received a copy of the GNU Lesser General Public |

15 | License along with the GNU C Library; if not, see |

16 | <http://www.gnu.org/licenses/>. */ |

17 | |

18 | #ifndef _IEEE754_H |

19 | |

20 | #define _IEEE754_H 1 |

21 | #include <features.h> |

22 | |

23 | #include <endian.h> |

24 | |

25 | __BEGIN_DECLS |

26 | |

27 | union ieee754_float |

28 | { |

29 | float f; |

30 | |

31 | /* This is the IEEE 754 single-precision format. */ |

32 | struct |

33 | { |

34 | #if __BYTE_ORDER == __BIG_ENDIAN |

35 | unsigned int negative:1; |

36 | unsigned int exponent:8; |

37 | unsigned int mantissa:23; |

38 | #endif /* Big endian. */ |

39 | #if __BYTE_ORDER == __LITTLE_ENDIAN |

40 | unsigned int mantissa:23; |

41 | unsigned int exponent:8; |

42 | unsigned int negative:1; |

43 | #endif /* Little endian. */ |

44 | } ieee; |

45 | |

46 | /* This format makes it easier to see if a NaN is a signalling NaN. */ |

47 | struct |

48 | { |

49 | #if __BYTE_ORDER == __BIG_ENDIAN |

50 | unsigned int negative:1; |

51 | unsigned int exponent:8; |

52 | unsigned int quiet_nan:1; |

53 | unsigned int mantissa:22; |

54 | #endif /* Big endian. */ |

55 | #if __BYTE_ORDER == __LITTLE_ENDIAN |

56 | unsigned int mantissa:22; |

57 | unsigned int quiet_nan:1; |

58 | unsigned int exponent:8; |

59 | unsigned int negative:1; |

60 | #endif /* Little endian. */ |

61 | } ieee_nan; |

62 | }; |

63 | |

64 | #define IEEE754_FLOAT_BIAS 0x7f /* Added to exponent. */ |

65 | |

66 | |

67 | union ieee754_double |

68 | { |

69 | double d; |

70 | |

71 | /* This is the IEEE 754 double-precision format. */ |

72 | struct |

73 | { |

74 | #if __BYTE_ORDER == __BIG_ENDIAN |

75 | unsigned int negative:1; |

76 | unsigned int exponent:11; |

77 | /* Together these comprise the mantissa. */ |

78 | unsigned int mantissa0:20; |

79 | unsigned int mantissa1:32; |

80 | #endif /* Big endian. */ |

81 | #if __BYTE_ORDER == __LITTLE_ENDIAN |

82 | # if __FLOAT_WORD_ORDER == __BIG_ENDIAN |

83 | unsigned int mantissa0:20; |

84 | unsigned int exponent:11; |

85 | unsigned int negative:1; |

86 | unsigned int mantissa1:32; |

87 | # else |

88 | /* Together these comprise the mantissa. */ |

89 | unsigned int mantissa1:32; |

90 | unsigned int mantissa0:20; |

91 | unsigned int exponent:11; |

92 | unsigned int negative:1; |

93 | # endif |

94 | #endif /* Little endian. */ |

95 | } ieee; |

96 | |

97 | /* This format makes it easier to see if a NaN is a signalling NaN. */ |

98 | struct |

99 | { |

100 | #if __BYTE_ORDER == __BIG_ENDIAN |

101 | unsigned int negative:1; |

102 | unsigned int exponent:11; |

103 | unsigned int quiet_nan:1; |

104 | /* Together these comprise the mantissa. */ |

105 | unsigned int mantissa0:19; |

106 | unsigned int mantissa1:32; |

107 | #else |

108 | # if __FLOAT_WORD_ORDER == __BIG_ENDIAN |

109 | unsigned int mantissa0:19; |

110 | unsigned int quiet_nan:1; |

111 | unsigned int exponent:11; |

112 | unsigned int negative:1; |

113 | unsigned int mantissa1:32; |

114 | # else |

115 | /* Together these comprise the mantissa. */ |

116 | unsigned int mantissa1:32; |

117 | unsigned int mantissa0:19; |

118 | unsigned int quiet_nan:1; |

119 | unsigned int exponent:11; |

120 | unsigned int negative:1; |

121 | # endif |

122 | #endif |

123 | } ieee_nan; |

124 | }; |

125 | |

126 | #define IEEE754_DOUBLE_BIAS 0x3ff /* Added to exponent. */ |

127 | |

128 | |

129 | union ieee854_long_double |

130 | { |

131 | long double d; |

132 | |

133 | /* This is the IEEE 854 double-extended-precision format. */ |

134 | struct |

135 | { |

136 | #if __BYTE_ORDER == __BIG_ENDIAN |

137 | unsigned int negative:1; |

138 | unsigned int exponent:15; |

139 | unsigned int empty:16; |

140 | unsigned int mantissa0:32; |

141 | unsigned int mantissa1:32; |

142 | #endif |

143 | #if __BYTE_ORDER == __LITTLE_ENDIAN |

144 | # if __FLOAT_WORD_ORDER == __BIG_ENDIAN |

145 | unsigned int exponent:15; |

146 | unsigned int negative:1; |

147 | unsigned int empty:16; |

148 | unsigned int mantissa0:32; |

149 | unsigned int mantissa1:32; |

150 | # else |

151 | unsigned int mantissa1:32; |

152 | unsigned int mantissa0:32; |

153 | unsigned int exponent:15; |

154 | unsigned int negative:1; |

155 | unsigned int empty:16; |

156 | # endif |

157 | #endif |

158 | } ieee; |

159 | |

160 | /* This is for NaNs in the IEEE 854 double-extended-precision format. */ |

161 | struct |

162 | { |

163 | #if __BYTE_ORDER == __BIG_ENDIAN |

164 | unsigned int negative:1; |

165 | unsigned int exponent:15; |

166 | unsigned int empty:16; |

167 | unsigned int one:1; |

168 | unsigned int quiet_nan:1; |

169 | unsigned int mantissa0:30; |

170 | unsigned int mantissa1:32; |

171 | #endif |

172 | #if __BYTE_ORDER == __LITTLE_ENDIAN |

173 | # if __FLOAT_WORD_ORDER == __BIG_ENDIAN |

174 | unsigned int exponent:15; |

175 | unsigned int negative:1; |

176 | unsigned int empty:16; |

177 | unsigned int mantissa0:30; |

178 | unsigned int quiet_nan:1; |

179 | unsigned int one:1; |

180 | unsigned int mantissa1:32; |

181 | # else |

182 | unsigned int mantissa1:32; |

183 | unsigned int mantissa0:30; |

184 | unsigned int quiet_nan:1; |

185 | unsigned int one:1; |

186 | unsigned int exponent:15; |

187 | unsigned int negative:1; |

188 | unsigned int empty:16; |

189 | # endif |

190 | #endif |

191 | } ieee_nan; |

192 | }; |

193 | |

194 | #define IEEE854_LONG_DOUBLE_BIAS 0x3fff |

195 | |

196 | __END_DECLS |

197 | |

198 | #endif /* ieee754.h */ |

199 |