Implement integer? and boolean? predicates

scm/inc/compiler.scm

@@ -56,6 +56,21 @@
        (emit "sete %al")                      ; set low byte of %eax to 1 if cmp succeeded
        (emit "sall $~a,  %eax" boolean-shift) ; construct correctly tagged boolean value
        (emit "xorl $31, %eax"))
       ((integer?)
        (emit-expr (primcall-operand1 x))
        (emit "andl $~a, %eax" #b11)
        (emit "movl $0,  %eax")
        (emit "sete %al")
        (emit "sall $~a,  %eax" boolean-shift)
        (emit "xorl $31, %eax"))
       ((boolean?)
        (emit-expr (primcall-operand1 x))
        (emit "andl $~a, %eax" #b0011111)
        (emit "cmpl $~a,  %eax" #b0011111)
        (emit "movl $0,  %eax")
        (emit "sete %al")
        (emit "sall $~a,  %eax" boolean-shift)
        (emit "xorl $31, %eax"))
       ))))
(define (compile-program x)
@@ -65,4 +80,4 @@
  (emit-expr x)
  (emit "ret"))
(compile-program '(zero? -1))
(compile-program '(boolean? #f))