s-arit64.adb: (Le3): New function, used by Scaled_Divide

s-arit64.adb: (Le3): New function, used by Scaled_Divide

2004-10-26  Robert Dewar  <dewar@gnat.com>

	* s-arit64.adb: (Le3): New function, used by Scaled_Divide
	(Sub3): New procedure, used by Scaled_Divide
	(Scaled_Divide): Substantial rewrite, avoid duplicated code, and also
	correct more than one instance of failure to propagate carries
	correctly.
	(Double_Divide): Handle overflow case of largest negative number
	divided by minus one.

	* s-arit64.ads (Double_Divide): Document that overflow can occur in
	the case of a quotient value out of range.
	Fix comments.

From-SVN: r89663