* optimization: bitwise OR forms can now trigger modular arithmetic as well,
when the result is known to be negative.
* optimization: recognize more cases of useless LOGAND/LOGIOR with constants.
+ * optimization: comparisons between rationals and constant floats or between
+ integers and constant ratios are now converted to rationals/integers at
+ compile time.
* bug fix: problems with NCONC type derivation (reported by Jerry James).
* bug fix: EXPT type derivation no longer constructs bogus floating-point
types. (reported by Vsevolod Dyomkin)