8.6.1.1120 D= d-equals DOUBLE
flag is true if and only if xd1 is bit-for-bit the same as xd2.
Testing:
T{ -1. 0. D= -> <FALSE> }T
T{ -1. 1. D= -> <FALSE> }T
T{ 0. -1. D= -> <FALSE> }T
T{ 0. 0. D= -> <TRUE> }T
T{ 0. 1. D= -> <FALSE> }T
T{ 1. -1. D= -> <FALSE> }T
T{ 1. 0. D= -> <FALSE> }T
T{ 1. 1. D= -> <TRUE> }T
T{ 0 -1 0 -1 D= -> <TRUE> }T
T{ 0 -1 0 0 D= -> <FALSE> }T
T{ 0 -1 0 1 D= -> <FALSE> }T
T{ 0 0 0 -1 D= -> <FALSE> }T
T{ 0 0 0 0 D= -> <TRUE> }T
T{ 0 0 0 1 D= -> <FALSE> }T
T{ 0 1 0 -1 D= -> <FALSE> }T
T{ 0 1 0 0 D= -> <FALSE> }T
T{ 0 1 0 1 D= -> <TRUE> }T
T{ MAX-2INT MIN-2INT D= -> <FALSE> }T
T{ MAX-2INT 0. D= -> <FALSE> }T
T{ MAX-2INT MAX-2INT D= -> <TRUE> }T
T{ MAX-2INT HI-2INT D= -> <FALSE> }T
T{ MAX-2INT MIN-2INT D= -> <FALSE> }T
T{ MIN-2INT MIN-2INT D= -> <TRUE> }T
T{ MIN-2INT LO-2INT D= -> <FALSE> }T
T{ MIN-2INT MAX-2INT D= -> <FALSE> }T