Convert CFXBR,CFDBR,CFEBR,CGXBR,CGDBR,CGEBR to softfloat
Corrections to CFEBR,CGEBR,CFDBR,CGDBR,CFXBR,CGXBR

1. Raise inexact condition with invalid
2. Return -MAX_INT instead of +MAX_INT for NaN
Add softfloat exp and fract functions
Convert THDR,THDER to softfloat