tweak case fixnum-only dispatch

Use `fixnum?` instead of `fixnum-for-any-platform?` when
only fixnums-on-any-platform are relevant.

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

@@ -572,6 +572,33 @@
   (test 1 f #s(o n e))
   (test (void) f #f))
 
+;; Make sure a mixture of fixnums and non-fixnums works:
+(let ()
+  (define (f x)
+    (case x
+      [(1) 'one]
+      [(1000) 'onek]
+      [(1001) 'onek+]
+      [(1002) 'onek+]
+      [(1003) 'onek+]
+      [(1000000) 'onem]
+      [(1000000000) 'onet]
+      [(1000000000000) 'oneqd]
+      [(1000000000001) 'oneqd+]
+      [(1000000000002) 'oneqd+]
+      [(1000000000003) 'oneqd+]
+      [(1000000000000000) 'oneqt]
+      [(1000000000000000000) 'ones]
+      [(1000000000000000001) 'ones+]
+      [(1000000000000000002) 'ones+]))
+  (test 'one f 1)
+  (test 'onek f 1000)
+  (test 'onem f 1000000)
+  (test 'onet f 1000000000)
+  (test 'oneqd f 1000000000000)
+  (test 'oneqt f 1000000000000000)
+  (test 'ones f 1000000000000000000))
+
 (test #t 'and (and (= 2 2) (> 2 1)))
 (test #f 'and (and (= 2 2) (< 2 1)))
 (test '(f g) 'and (and 1 2 'c '(f g)))

racket/collects/racket/private/case.rkt

@@ -167,7 +167,11 @@
                                          #,exp))]
                           [exp (if (null? (consts-fixnum ks))
                                    exp
-                                   #`(if (fixnum-for-every-system? v)
+                                   #`(if #,(if (null? (consts-other ks))
+                                               ;; can check for fixnum
+                                               #'(fixnum? v)
+                                               ;; maybe could-be-fixnum numbers are in `others`
+                                               #'(fixnum-for-every-system? v))
                                          #,(dispatch-fixnum #'v (consts-fixnum ks))
                                          #,exp))])
                      exp)])

racket/src/cs/schemified/expander.scm

@@ -465,9 +465,6 @@
     (if (list? a_0)
       (append a_0 b_0)
       (raise-argument-error 'unquote-splicing "list?" a_0))))
-(define fixnum-for-every-system?
-  (lambda (v_0)
-    (if (fixnum? v_0) (if (fx>= v_0 -536870912) (fx<= v_0 536870911) #f) #f)))
 (define bad-list$1
   (|#%name|
    bad-list
@@ -24569,7 +24566,7 @@
                (begin
                  (let ((type_0 (read-byte/no-eof i_0)))
                    (let ((index_0
-                          (if (fixnum-for-every-system? type_0)
+                          (if (fixnum? type_0)
                             (if (if (unsafe-fx>= type_0 1)
                                   (unsafe-fx< type_0 42)
                                   #f)

racket/src/cs/schemified/schemify.scm

@@ -47963,7 +47963,7 @@
                (begin
                  (let ((type_0 (read-byte/no-eof i_0)))
                    (let ((index_0
-                          (if (fixnum-for-every-system? type_0)
+                          (if (fixnum? type_0)
                             (if (if (unsafe-fx>= type_0 1)
                                   (unsafe-fx< type_0 42)
                                   #f)