+
+(defun power-of-two-limit-p (x)
+ (and (fixnump x)
+ (= (logcount (1+ x)) 1)))
+
+(define-vop (test-fixnum-mod-power-of-two)
+ (:args (value :scs (any-reg descriptor-reg
+ unsigned-reg signed-reg
+ immediate)))
+ (:arg-types *
+ (:constant (satisfies power-of-two-limit-p)))
+ (:translate sb!c::fixnum-mod-p)
+ (:conditional :e)
+ (:info hi)
+ (:save-p :compute-only)
+ (:policy :fast-safe)
+ (:generator 4
+ (aver (not (sc-is value immediate)))
+ (let* ((fixnum-hi (if (sc-is value unsigned-reg signed-reg)
+ hi
+ (fixnumize hi))))
+ (inst test value (lognot fixnum-hi)))))
+
+(define-vop (test-fixnum-mod-tagged-unsigned)
+ (:args (value :scs (any-reg descriptor-reg
+ unsigned-reg signed-reg
+ immediate)))
+ (:arg-types (:or tagged-num unsigned-num signed-num)
+ (:constant fixnum))
+ (:translate sb!c::fixnum-mod-p)
+ (:conditional :be)
+ (:info hi)
+ (:save-p :compute-only)
+ (:policy :fast-safe)
+ (:generator 5
+ (aver (not (sc-is value immediate)))
+ (let ((fixnum-hi (if (sc-is value unsigned-reg signed-reg)
+ hi
+ (fixnumize hi))))
+ (inst cmp value fixnum-hi))))
+
+(define-vop (test-fixnum-mod-*)
+ (:args (value :scs (any-reg descriptor-reg)))
+ (:arg-types * (:constant fixnum))
+ (:translate sb!c::fixnum-mod-p)
+ (:conditional)
+ (:info target not-p hi)
+ (:save-p :compute-only)
+ (:policy :fast-safe)
+ (:generator 6
+ (let* ((fixnum-hi (fixnumize hi))
+ (skip (gen-label)))
+ (generate-fixnum-test value)
+ (inst jmp :ne (if not-p target skip))
+ (inst cmp value fixnum-hi)
+ (inst jmp (if not-p :a :be) target)
+ (emit-label skip))))
+