fieee2ms.gml

来自「开放源码的编译器open watcom 1.6.0版的源代码」· GML 代码 · 共 60 行

.func _fieeetomsbin
#include <math.h>
extern int _fieeetomsbin( float *src, float *dest );
.ixfunc2 '&Math' &func
.funcend
.desc begin
The &func function loads the float pointed to by
.arg src
in IEEE format and converts it to Microsoft binary format, storing the
result into the float pointed to by
.arg dest.
.np
For &func, IEEE Nan's and Infinities will cause overflow.
IEEE denormals will be converted if within range.
Otherwise, they will be converted to 0 in the Microsoft binary format.
.np
The range of Microsoft binary format floats is 2.938736e-39 to
1.701412e+38.
The range of Microsoft binary format doubles is 2.938735877056e-39 to
1.701411834605e+38.
.np
Microsoft Binary Format was used by early versions of Microsoft
QuickBASIC before coprocessors became standard.
.desc end
.return begin
The &func function returns 0 if the conversion was successful.
Otherwise, it returns 1 if conversion would cause an overflow.
.return end
.see begin
.seelist &function. _dieeetomsbin _dmsbintoieee _fieeetomsbin _fmsbintoieee
.see end
.exmp begin
#include <stdio.h>
#include <math.h>

void main()
  {
    float fieee, fmsb;
    double dieee, dmsb;

    fieee = 0.5;
    dieee = -2.0;

    /* Convert IEEE format to Microsoft binary format */
    _fieeetomsbin( &fieee, &fmsb );
    _dieeetomsbin( &dieee, &dmsb );

    /* Convert Microsoft binary format back to IEEE format */
    _fmsbintoieee( &fmsb, &fieee );
    _dmsbintoieee( &dmsb, &dieee );

    /* Display results */
    printf( "fieee = %f, dieee = %f\n", fieee, dieee );
  }
.exmp output
fieee = 0.500000, dieee = -2.000000
.exmp end
.class WATCOM
.system