* optimization: SLEEP doesn't cons on non-immediate floats and on ratios.
* optimization: (mod fixnum) type-checks are performed using one unsigned
comparison, instead of two.
+ * optimization: enable more modular arithmetic transforms in the presence of
+ conditionals.
* 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)