Hi All!

There are some more trick(idea).

....
SUBWF REG,W
SUBWF REG,F
ADDWF REG,W
....
the code sequency above may be used to exchange W with some REG(s)
at one time with comparision greater_or_equal or so.

For example:

SUBWF REG0,W ;REG0(old)-W
SKPC         ;REG0(old)>=W
GOTO LABEL1

SUBWF REG0,W ;restore i.e. REG0-(REG0-W)=W
SUBWF REG1,W
SKPC         ;REG1>=W
GOTO LABEL2

SUBWF REG1,W ;restore W
.....

LABEL1:
SUBWF REG0,F ;REG0(new)=REG0(old)-(REG0(old)-W)=W
ADDWF REG0,W ;W=REG0(new)+(REG0(old)-W)=REG0(old)
....

LABEL2:
SUBWF REG1,F ;=W
ADDWF REG1,W ;=REG1(old)
....

WBR Dmitry.