src/float/misc/cl_F_leastneg.cc

   1 // least_negative_float().
   2
   3 // General includes.
   4 #include "base/cl_sysdep.h"
   5
   6 // Specification.
   7 #include "cln/float.h"
   8
   9 // Implementation.
  10
  11 #include "float/cl_F.h"
  12 #include "float/sfloat/cl_SF.h"
  13 #include "float/ffloat/cl_FF.h"
  14 #include "float/dfloat/cl_DF.h"
  15 #include "float/lfloat/cl_LF.h"
  16 #include "float/lfloat/cl_LF_impl.h"
  17
  18 namespace cln {
  19
  20 static inline const cl_LF least_negative_LF (uintC len)
  21 {
  22         var Lfloat erg = allocate_lfloat(len,LF_exp_low,-1);
  23         #if CL_DS_BIG_ENDIAN_P
  24           TheLfloat(erg)->data[0] = bit(intDsize-1);
  25           clear_loop_up(&TheLfloat(erg)->data[1],len-1);
  26         #else
  27           var uintD* ptr = clear_loop_up(&TheLfloat(erg)->data[0],len-1);
  28           *ptr = bit(intDsize-1);
  29         #endif
  30         return erg;
  31 }
  32
  33 const cl_F least_negative_float (float_format_t f)
  34 {
  35         // Exponent so klein wie möglich, Mantisse 10...0, Vorzeichen -.
  36
  37         static const cl_SF least_negative_SF =
  38                 make_SF(-1,SF_exp_low,bit(SF_mant_len));
  39
  40         static const cl_FF least_negative_FF =
  41                 encode_FF(-1,FF_exp_low-FF_exp_mid,bit(FF_mant_len));
  42
  43         static const cl_DF least_negative_DF =
  44         #if (cl_word_size==64)
  45                 encode_DF(-1,DF_exp_low-DF_exp_mid,bit(DF_mant_len));
  46         #else
  47                 encode_DF(-1,DF_exp_low-DF_exp_mid,bit(DF_mant_len-32),0);
  48         #endif
  49
  50         floatformatcase((uintC)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 }  // namespace cln
  59