Promote more literals at compile-time.

collects/tests/typed-scheme/optimizer/tests/invalid-float-promotion.rkt

@@ -1,8 +1,11 @@
 #;
 (
 0.5
+2.0
 )
 
 #lang typed/scheme
 #:optimize
+;; the ann are necessary, since (* PosReal Float) -> Float (exact 0 is not in PosReal)
 (/ (ann 1 Integer) 2.0) ; result is not a float, can't optimize
+(* (ann 2/3 Exact-Rational) 3.0)

collects/tests/typed-scheme/optimizer/tests/rational-literal.rkt

@@ -0,0 +1,8 @@
+#;
+(
+rational-literal.rkt line 8 col 1 - + - binary float
+1.95
+)
+#lang typed/racket #:optimize
+;; rational literals should be promoted to floats at compile time
+(+ 3/4 1.2)

collects/typed-scheme/optimizer/float.rkt

@@ -67,9 +67,10 @@
   #:commit
   ;; we can convert literals right away
   (pattern (quote n)
-           #:when (exact-integer? (syntax->datum #'n))
+           #:when (and (real?  (syntax->datum #'n))
+                       (exact? (syntax->datum #'n)))
            #:with opt
-           (datum->syntax #'here (->fl (syntax->datum #'n))))
+           (datum->syntax #'here (exact->inexact (syntax->datum #'n))))
   (pattern e:fixnum-expr
            #:with opt #'(unsafe-fx->fl e.opt))
   (pattern e:int-expr