add fixnum-for-every-system?

The `case` macro needs to use the new predicate instead of `fixnum?`,
but delay swittching over until Typed Racket is ready.

pkgs/base/info.rkt

@@ -12,7 +12,7 @@
 
 (define collection 'multi)
 
-(define version "7.3.0.10")
+(define version "7.3.0.11")
 
 (define deps `("racket-lib"
                ["racket" #:version ,version]))

pkgs/racket-doc/scribblings/reference/fixnums.scrbl

@@ -99,6 +99,16 @@ Safe versions of @racket[unsafe-fx=], @racket[unsafe-fx<],
 
 Safe versions of @racket[unsafe-fx->fl] and @racket[unsafe-fl->fx].}
 
+
+@defproc[(fixnum-for-every-system? [v any/c]) boolean?]{
+
+Returns @racket[#t] if @racket[v] is a @tech{fixnum} and is
+represented by fixnum by every Racket implementation, @racket[#f]
+otherwise.
+
+@history[#:added "7.3.0.11"]}
+
+
 @; ------------------------------------------------------------
 
 @section[#:tag "fxvectors"]{Fixnum Vectors}

pkgs/racket-test-core/tests/racket/fixnum.rktl

@@ -1,15 +1,26 @@
 (load-relative "loadtest.rktl")
 (Section 'fixnum)
-(require scheme/fixnum
-         scheme/unsafe/ops
+(require racket/fixnum
+         racket/unsafe/ops
          "for-util.rkt")
 
-(define 64-bit? (fixnum? (expt 2 33)))
+(define 64-bit? (= (system-type 'word) 64))
 
-(define (fixnum-width) (if 64-bit? 63 31))
-(define (least-fixnum) (if 64-bit? (- (expt 2 62)) -1073741824))
-(define (greatest-fixnum) (if 64-bit? (- (expt 2 62) 1) +1073741823))
+(define (fixnum-width) (if (eq? 'racket (system-type))
+                           (if 64-bit? 63 31)
+                           (if 64-bit? 61 30)))
+(define (least-fixnum) (- (expt 2 (fixnum-width))))
+(define (greatest-fixnum) (sub1 (expt 2 (fixnum-width))))
 
+(test #t fixnum-for-every-system? 0)
+(test #t fixnum-for-every-system? -100)
+(test #t fixnum-for-every-system? 100)
+(test #t fixnum-for-every-system? (- (expt 2 29)))
+(test #t fixnum-for-every-system? (sub1 (expt 2 29)))
+(test #t fixnum? (- (expt 2 29)))
+(test #t fixnum? (sub1 (expt 2 29)))
+(test #f fixnum-for-every-system? (sub1 (- (expt 2 29))))
+(test #f fixnum-for-every-system? (expt 2 29))
 
 (define unary-table 
   (list (list fxnot unsafe-fxnot)

racket/collects/racket/fixnum.rkt

@@ -2,6 +2,7 @@
 
 (require '#%flfxnum
          "private/vector-wraps.rkt"
+         "private/fixnum.rkt"
          "unsafe/ops.rkt"
          (for-syntax racket/base))
 
@@ -13,6 +14,7 @@
          fxnot fxrshift fxlshift
          fx>= fx> fx= fx< fx<=
          fxmin fxmax
+         fixnum-for-every-system?
          fxvector? fxvector make-fxvector 
          shared-fxvector make-shared-fxvector
          fxvector-length fxvector-ref fxvector-set!

racket/collects/racket/private/case.rkt

@@ -3,12 +3,11 @@
 ;;       [http://scheme2006.cs.uchicago.edu/07-clinger.pdf]
 
 (module case '#%kernel
-  (#%require '#%paramz '#%unsafe "small-scheme.rkt" "define.rkt"
+  (#%require '#%paramz '#%unsafe "small-scheme.rkt" "define.rkt" "fixnum.rkt"
              (for-syntax '#%kernel "small-scheme.rkt" "stxcase-scheme.rkt"
-                         "qqstx.rkt" "define.rkt" "sort.rkt"))
+                         "qqstx.rkt" "define.rkt" "sort.rkt" "fixnum.rkt"))
   (#%provide case)
   
-  
   (define-syntax (case stx)
     (syntax-case stx (else)
       ;; Empty case
@@ -158,13 +157,12 @@
                                          #,exp))]
                           [exp (if (null? (consts-fixnum ks))
                                    exp
-                                   #`(if (fixnum? v)
+                                   #`(if (fixnum? #;fixnum-for-every-system? v)
                                          #,(dispatch-fixnum #'v (consts-fixnum ks))
                                          #,exp))])
                      exp)])
             #,(index-binary-search #'index #'([xs ...] [es ...] ...))))]))
 
-    
   (begin-for-syntax
     (define *sequential-threshold* 12)
     (define *hash-threshold*       10)
@@ -196,7 +194,7 @@
                             [else
                              (let ([y (syntax->datum (car ys))])
                                (cond [(duplicate? y) (inner f s c o (cdr ys))]
-                                     [(fixnum? y)    (inner (add f y idx) s c o (cdr ys))]
+                                     [(fixnum? #;fixnum-for-every-system? y) (inner (add f y idx) s c o (cdr ys))]
                                      [(symbol? y)    (inner f (add s y idx) c o (cdr ys))]
                                      [(keyword? y)   (inner f (add s y idx) c o (cdr ys))]
                                      [(char? y)      (inner f s (add c y idx) o (cdr ys))]

racket/collects/racket/private/fixnum.rkt

@@ -0,0 +1,14 @@
+(module fixnum '#%kernel
+  (#%require '#%flfxnum)
+  (#%provide fixnum-for-every-system?)
+
+  ;; Smallest number of bits used for a fixnum across Racket
+  ;; implementation is 30 bits.
+
+  (define-values (fixnum-for-every-system?)
+    (lambda (v)
+      (if (fixnum? v)
+          (if (fx>= v -536870912)
+              (fx<= v 536870911)
+              #f)
+          #f))))

racket/src/racket/src/schvers.h

@@ -16,7 +16,7 @@
 #define MZSCHEME_VERSION_X 7
 #define MZSCHEME_VERSION_Y 3
 #define MZSCHEME_VERSION_Z 0
-#define MZSCHEME_VERSION_W 10
+#define MZSCHEME_VERSION_W 11
 
 /* A level of indirection makes `#` work as needed: */
 #define AS_a_STR_HELPER(x) #x