src/float/misc/cl_F_leastneg.cc

   1 // least_negative_float().
   2
   3 // General includes.
   4 #include "cl_sysdep.h"
   5
   6 CL_PROVIDE(cl_F_leastneg)
   7
   8 // Specification.
   9 #include "cl_float.h"
  10
  11 // Implementation.
  12
  13 #include "cl_F.h"
  14 #include "cl_SF.h"
  15 #include "cl_FF.h"
  16 #include "cl_DF.h"
  17 #include "cl_LF.h"
  18 #include "cl_LF_impl.h"
  19
  20 // Exponent so klein wie möglich, Mantisse 10...0, Vorzeichen -.
  21
  22 static const cl_SF least_negative_SF =
  23         make_SF(-1,SF_exp_low,bit(SF_mant_len));
  24
  25 static const cl_FF least_negative_FF =
  26         encode_FF(-1,FF_exp_low-FF_exp_mid,bit(FF_mant_len));
  27
  28 static const cl_DF least_negative_DF =
  29         #if (cl_word_size==64)
  30           encode_DF(-1,DF_exp_low-DF_exp_mid,bit(DF_mant_len));
  31         #else
  32           encode_DF(-1,DF_exp_low-DF_exp_mid,bit(DF_mant_len-32),0);
  33         #endif
  34
  35 inline const cl_LF least_negative_LF (uintC len)
  36 {
  37         var Lfloat erg = allocate_lfloat(len,LF_exp_low,-1);
  38         #if CL_DS_BIG_ENDIAN_P
  39           TheLfloat(erg)->data[0] = bit(intDsize-1);
  40           clear_loop_up(&TheLfloat(erg)->data[1],len-1);
  41         #else
  42           var uintD* ptr = clear_loop_up(&TheLfloat(erg)->data[0],len-1);
  43           *ptr = bit(intDsize-1);
  44         #endif
  45         return erg;
  46 }
  47
  48 const cl_F least_negative_float (cl_float_format_t f)
  49 {
  50         floatformatcase((uintL)f
  51         ,       return least_negative_SF;
  52         ,       return least_negative_FF;
  53         ,       return least_negative_DF;
  54         ,       return least_negative_LF(len);
  55         );
  56 }
  57
  58 CL_PROVIDE_END(cl_F_leastneg)