arch/arm/nwfpe/softfloat.h

   1
   2 /*
   3 ===============================================================================
   4
   5 This C header file is part of the SoftFloat IEC/IEEE Floating-point
   6 Arithmetic Package, Release 2.
   7
   8 Written by John R. Hauser.  This work was made possible in part by the
   9 International Computer Science Institute, located at Suite 600, 1947 Center
  10 Street, Berkeley, California 94704.  Funding was partially provided by the
  11 National Science Foundation under grant MIP-9311980.  The original version
  12 of this code was written as part of a project to build a fixed-point vector
  13 processor in collaboration with the University of California at Berkeley,
  14 overseen by Profs. Nelson Morgan and John Wawrzynek.  More information
  15 is available through the Web page `http://HTTP.CS.Berkeley.EDU/~jhauser/
  16 arithmetic/softfloat.html'.
  17
  18 THIS SOFTWARE IS DISTRIBUTED AS IS, FOR FREE.  Although reasonable effort
  19 has been made to avoid it, THIS SOFTWARE MAY CONTAIN FAULTS THAT WILL AT
  20 TIMES RESULT IN INCORRECT BEHAVIOR.  USE OF THIS SOFTWARE IS RESTRICTED TO
  21 PERSONS AND ORGANIZATIONS WHO CAN AND WILL TAKE FULL RESPONSIBILITY FOR ANY
  22 AND ALL LOSSES, COSTS, OR OTHER PROBLEMS ARISING FROM ITS USE.
  23
  24 Derivative works are acceptable, even for commercial purposes, so long as
  25 (1) they include prominent notice that the work is derivative, and (2) they
  26 include prominent notice akin to these three paragraphs for those parts of
  27 this code that are retained.
  28
  29 ===============================================================================
  30 */
  31
  32 #ifndef __SOFTFLOAT_H__
  33 #define __SOFTFLOAT_H__
  34
  35
  36 /*
  37 -------------------------------------------------------------------------------
  38 The macro `FLOATX80' must be defined to enable the extended double-precision
  39 floating-point format `floatx80'.  If this macro is not defined, the
  40 `floatx80' type will not be defined, and none of the functions that either
  41 input or output the `floatx80' type will be defined.
  42 -------------------------------------------------------------------------------
  43 */
  44 #ifdef CONFIG_FPE_NWFPE_XP
  45 #define FLOATX80
  46 #endif
  47
  48 /*
  49 -------------------------------------------------------------------------------
  50 Software IEC/IEEE floating-point types.
  51 -------------------------------------------------------------------------------
  52 */
  53 typedef u32 float32;
  54 typedef u64 float64;
  55 typedef struct {
  56 #ifdef __ARMEB__
  57     u16 __padding;
  58     u16 high;
  59 #else
  60     u16 high;
  61     u16 __padding;
  62 #endif
  63     u64 low;
  64 }  __attribute__ ((packed,aligned(4))) floatx80;
  65
  66 /*
  67 -------------------------------------------------------------------------------
  68 Software IEC/IEEE floating-point underflow tininess-detection mode.
  69 -------------------------------------------------------------------------------
  70 */
  71 extern signed char float_detect_tininess;
  72 enum {
  73     float_tininess_after_rounding  = 0,
  74     float_tininess_before_rounding = 1
  75 };
  76
  77 /*
  78 -------------------------------------------------------------------------------
  79 Software IEC/IEEE floating-point rounding mode.
  80 -------------------------------------------------------------------------------
  81 */
  82 //extern int8 float_rounding_mode;
  83 enum {
  84     float_round_nearest_even = 0,
  85     float_round_to_zero      = 1,
  86     float_round_down         = 2,
  87     float_round_up           = 3
  88 };
  89
  90 /*
  91 -------------------------------------------------------------------------------
  92 Software IEC/IEEE floating-point exception flags.
  93 -------------------------------------------------------------------------------
  94 enum {
  95     float_flag_inexact   =  1,
  96     float_flag_underflow =  2,
  97     float_flag_overflow  =  4,
  98     float_flag_divbyzero =  8,
  99     float_flag_invalid   = 16
 100 };
 101
 102 ScottB: November 4, 1998
 103 Changed the enumeration to match the bit order in the FPA11.
 104 */
 105
 106 enum {
 107     float_flag_invalid   =  1,
 108     float_flag_divbyzero =  2,
 109     float_flag_overflow  =  4,
 110     float_flag_underflow =  8,
 111     float_flag_inexact   = 16
 112 };
 113
 114 /*
 115 -------------------------------------------------------------------------------
 116 Routine to raise any or all of the software IEC/IEEE floating-point
 117 exception flags.
 118 -------------------------------------------------------------------------------
 119 */
 120 void float_raise( signed char );
 121
 122 /*
 123 -------------------------------------------------------------------------------
 124 Software IEC/IEEE integer-to-floating-point conversion routines.
 125 -------------------------------------------------------------------------------
 126 */
 127 float32 int32_to_float32( struct roundingData *, signed int );
 128 float64 int32_to_float64( signed int );
 129 #ifdef FLOATX80
 130 floatx80 int32_to_floatx80( signed int );
 131 #endif
 132
 133 /*
 134 -------------------------------------------------------------------------------
 135 Software IEC/IEEE single-precision conversion routines.
 136 -------------------------------------------------------------------------------
 137 */
 138 signed int float32_to_int32( struct roundingData *, float32 );
 139 signed int float32_to_int32_round_to_zero( float32 );
 140 float64 float32_to_float64( float32 );
 141 #ifdef FLOATX80
 142 floatx80 float32_to_floatx80( float32 );
 143 #endif
 144
 145 /*
 146 -------------------------------------------------------------------------------
 147 Software IEC/IEEE single-precision operations.
 148 -------------------------------------------------------------------------------
 149 */
 150 float32 float32_round_to_int( struct roundingData*, float32 );
 151 float32 float32_add( struct roundingData *, float32, float32 );
 152 float32 float32_sub( struct roundingData *, float32, float32 );
 153 float32 float32_mul( struct roundingData *, float32, float32 );
 154 float32 float32_div( struct roundingData *, float32, float32 );
 155 float32 float32_rem( struct roundingData *, float32, float32 );
 156 float32 float32_sqrt( struct roundingData*, float32 );
 157 char float32_eq( float32, float32 );
 158 char float32_le( float32, float32 );
 159 char float32_lt( float32, float32 );
 160 char float32_eq_signaling( float32, float32 );
 161 char float32_le_quiet( float32, float32 );
 162 char float32_lt_quiet( float32, float32 );
 163 char float32_is_signaling_nan( float32 );
 164
 165 /*
 166 -------------------------------------------------------------------------------
 167 Software IEC/IEEE double-precision conversion routines.
 168 -------------------------------------------------------------------------------
 169 */
 170 signed int float64_to_int32( struct roundingData *, float64 );
 171 signed int float64_to_int32_round_to_zero( float64 );
 172 float32 float64_to_float32( struct roundingData *, float64 );
 173 #ifdef FLOATX80
 174 floatx80 float64_to_floatx80( float64 );
 175 #endif
 176
 177 /*
 178 -------------------------------------------------------------------------------
 179 Software IEC/IEEE double-precision operations.
 180 -------------------------------------------------------------------------------
 181 */
 182 float64 float64_round_to_int( struct roundingData *, float64 );
 183 float64 float64_add( struct roundingData *, float64, float64 );
 184 float64 float64_sub( struct roundingData *, float64, float64 );
 185 float64 float64_mul( struct roundingData *, float64, float64 );
 186 float64 float64_div( struct roundingData *, float64, float64 );
 187 float64 float64_rem( struct roundingData *, float64, float64 );
 188 float64 float64_sqrt( struct roundingData *, float64 );
 189 char float64_eq( float64, float64 );
 190 char float64_le( float64, float64 );
 191 char float64_lt( float64, float64 );
 192 char float64_eq_signaling( float64, float64 );
 193 char float64_le_quiet( float64, float64 );
 194 char float64_lt_quiet( float64, float64 );
 195 char float64_is_signaling_nan( float64 );
 196
 197 #ifdef FLOATX80
 198
 199 /*
 200 -------------------------------------------------------------------------------
 201 Software IEC/IEEE extended double-precision conversion routines.
 202 -------------------------------------------------------------------------------
 203 */
 204 signed int floatx80_to_int32( struct roundingData *, floatx80 );
 205 signed int floatx80_to_int32_round_to_zero( floatx80 );
 206 float32 floatx80_to_float32( struct roundingData *, floatx80 );
 207 float64 floatx80_to_float64( struct roundingData *, floatx80 );
 208
 209 /*
 210 -------------------------------------------------------------------------------
 211 Software IEC/IEEE extended double-precision operations.
 212 -------------------------------------------------------------------------------
 213 */
 214 floatx80 floatx80_round_to_int( struct roundingData *, floatx80 );
 215 floatx80 floatx80_add( struct roundingData *, floatx80, floatx80 );
 216 floatx80 floatx80_sub( struct roundingData *, floatx80, floatx80 );
 217 floatx80 floatx80_mul( struct roundingData *, floatx80, floatx80 );
 218 floatx80 floatx80_div( struct roundingData *, floatx80, floatx80 );
 219 floatx80 floatx80_rem( struct roundingData *, floatx80, floatx80 );
 220 floatx80 floatx80_sqrt( struct roundingData *, floatx80 );
 221 char floatx80_eq( floatx80, floatx80 );
 222 char floatx80_le( floatx80, floatx80 );
 223 char floatx80_lt( floatx80, floatx80 );
 224 char floatx80_eq_signaling( floatx80, floatx80 );
 225 char floatx80_le_quiet( floatx80, floatx80 );
 226 char floatx80_lt_quiet( floatx80, floatx80 );
 227 char floatx80_is_signaling_nan( floatx80 );
 228
 229 #endif
 230
 231 static inline flag extractFloat32Sign(float32 a)
 232 {
 233         return a >> 31;
 234 }
 235
 236 static inline flag float32_eq_nocheck(float32 a, float32 b)
 237 {
 238         return (a == b) || ((bits32) ((a | b) << 1) == 0);
 239 }
 240
 241 static inline flag float32_lt_nocheck(float32 a, float32 b)
 242 {
 243         flag aSign, bSign;
 244
 245         aSign = extractFloat32Sign(a);
 246         bSign = extractFloat32Sign(b);
 247         if (aSign != bSign)
 248                 return aSign && ((bits32) ((a | b) << 1) != 0);
 249         return (a != b) && (aSign ^ (a < b));
 250 }
 251
 252 static inline flag extractFloat64Sign(float64 a)
 253 {
 254         return a >> 63;
 255 }
 256
 257 static inline flag float64_eq_nocheck(float64 a, float64 b)
 258 {
 259         return (a == b) || ((bits64) ((a | b) << 1) == 0);
 260 }
 261
 262 static inline flag float64_lt_nocheck(float64 a, float64 b)
 263 {
 264         flag aSign, bSign;
 265
 266         aSign = extractFloat64Sign(a);
 267         bSign = extractFloat64Sign(b);
 268         if (aSign != bSign)
 269                 return aSign && ((bits64) ((a | b) << 1) != 0);
 270         return (a != b) && (aSign ^ (a < b));
 271 }
 272
 273 extern flag float32_is_nan( float32 a );
 274 extern flag float64_is_nan( float64 a );
 275
 276 extern int32 float64_to_uint32( struct roundingData *roundData, float64 a );
 277 extern int32 float64_to_uint32_round_to_zero( float64 a );
 278
 279 #endif