Re: Cobol compiler date

> Actually, it probably would be a Character 19 C'19' for a
> simple move, and not a zone decimal equivalent.

It's a hard-coded character constant:

DATE1    DC    CL15'JAN  5,1966'

OS compilers weren't reentrant, so there is no move of
a constant C'19' to a work area.  Instead, the date is
built on top of the constant, and the whole modified field
is moved to the page header and the DATE-COMPILED paragraph.

> Next most likely would be a packed 1900 x'01900F', not a
> packed 19 x'019F' due to decimal alignment, but most
> manipulations would occur after converting to Character..
>
> Least likely would be a Binary 1900 or x'076C', and not Binary 
> 19 or x'0013', due to decimal alignment, but most manipulations
> would occur after converting to Character.

The date routine is fast but really inelegant code.  It
does a leap year check with TMs against the digit part
of the zoned decimal characters, pretending they're binary:

         TM    DATE1+10,X'01'
       BO    NOLEAP
         TM    DATE1+9,X'01'
       BO    DATDECOD    DECADE ODD
         TM    DATE1+10,X'02'
       BO    NOLEAP
       B     LEAP
DATDECOD TM    DATE1+10,X'02'
       BZ    NOLEAP
LEAP   LA    R4,156
       STC   R4,TABLE+9
NOLEAP SLL   R1,4
       LA    R1,12(1)
       STH   R1,INDATE

-- 
Kevin