diff --git a/benchmarks.larceny/results.Larceny-r6rs b/benchmarks.larceny/results.Larceny-r6rs
index 7b5f1b8..7eca1c3 100644
--- a/benchmarks.larceny/results.Larceny-r6rs
+++ b/benchmarks.larceny/results.Larceny-r6rs
@@ -8190,3 +8190,23 @@ Words allocated: 551809361
 Words reclaimed: 0
 Elapsed time...: 2246 ms (User: 2230 ms; System: 15 ms)
 Elapsed GC time: 753 ms (CPU: 762 in 2105 collections.)
+
+****************************
+Benchmarking Larceny-r6rs on Sat Jul 14 07:09:21 AST 2007 under Darwin Vesuvius.local 8.9.1 Darwin Kernel Version 8.9.1: Thu Feb 22 20:55:00 PST 2007; root:xnu-792.18.15~1/RELEASE_I386 i386 i386
+
+Testing fibfp under Larceny-r6rs
+Compiling...
+Larceny v0.93 "Deviated Prevert" (Nov 10 2006 04:27:45, precise:BSD Unix:unified)
+
+
+> 
+> 
+Running...
+Larceny v0.93 "Deviated Prevert" (Nov 10 2006 04:27:45, precise:BSD Unix:unified)
+
+
+> 
+Words allocated: 358610884
+Words reclaimed: 0
+Elapsed time...: 3289 ms (User: 3248 ms; System: 39 ms)
+Elapsed GC time: 486 ms (CPU: 489 in 1368 collections.)
diff --git a/src/ikarus.boot b/src/ikarus.boot
index f9cfd09..7c1adfe 100644
Binary files a/src/ikarus.boot and b/src/ikarus.boot differ
diff --git a/src/ikarus.compiler.ss b/src/ikarus.compiler.ss
index ce45a43..5bc3827 100644
--- a/src/ikarus.compiler.ss
+++ b/src/ikarus.compiler.ss
@@ -1796,19 +1796,23 @@
   (define disp-code-relocsize      8)
   (define disp-code-freevars      12)
   (define disp-code-data          16)
+  
   (define port-tag              #x3F)
-  (define input-port-tag        #x7F)
-  (define output-port-tag       #xBF)
-  (define input/output-port-tag #xFF)
+  (define output-port-tag       #x7F)
+  (define input-port-tag        #xBF)
+  ;(define input/output-port-tag #xFF)
   (define port-mask             #x3F)
-  (define disp-port-handler        4)
-  (define disp-port-input-buffer   8)
-  (define disp-port-input-index   12)
-  (define disp-port-input-size    16)
+  (define disp-port-buffer         4)
+  (define disp-port-index          8)
+  (define disp-port-size          12)
+  (define disp-port-handler       16)
   (define disp-port-output-buffer 20)
   (define disp-port-output-index  24)
   (define disp-port-output-size   28)
   (define port-size               32)
+
+
+
   (define disp-tcbucket-tconc 0)
   (define disp-tcbucket-key   4)
   (define disp-tcbucket-val   8)
diff --git a/src/ikarus.io-ports.ss b/src/ikarus.io-ports.ss
index e1cc79a..111b830 100644
--- a/src/ikarus.io-ports.ss
+++ b/src/ikarus.io-ports.ss
@@ -1,6 +1,6 @@
 
 (library (ikarus io-ports)
-  (export make-input-port make-output-port make-input/output-port
+  (export make-input-port make-output-port ;make-input/output-port
           port-handler
           port-input-buffer  port-output-buffer 
           port-input-index   set-port-input-index!
@@ -12,8 +12,10 @@
     (ikarus system $strings)
     (ikarus system $bytevectors)
     (ikarus system $fx)
-    (except (ikarus)  make-input-port make-output-port 
-         make-input/output-port port-handler
+    (except (ikarus)  
+         make-input-port make-output-port 
+         ;make-input/output-port 
+         port-handler
          port-input-buffer  port-output-buffer
          port-input-index   set-port-input-index!
          port-input-size    set-port-input-size!
@@ -75,21 +77,21 @@
               (error 'make-output-port "~s is not a bytevector" buffer))
           (error 'make-output-port "~s is not a procedure" handler))))
   ;;;
-  (define $make-input/output-port
-    (lambda (handler input-buffer output-buffer)
-       ($make-port/both handler
-                  input-buffer 0 ($bytevector-length input-buffer)
-                  output-buffer 0 ($bytevector-length output-buffer))))
+  ;(define $make-input/output-port
+  ;  (lambda (handler input-buffer output-buffer)
+  ;     ($make-port/both handler
+  ;                input-buffer 0 ($bytevector-length input-buffer)
+  ;                output-buffer 0 ($bytevector-length output-buffer))))
   ;;;
-  (define make-input/output-port
-    (lambda (handler input-buffer output-buffer)
-      (if (procedure? handler)
-          (if (bytevector? input-buffer)
-              (if (bytevector? output-buffer)
-                  ($make-input/output-port handler input-buffer output-buffer) 
-                  (error 'make-input/output-port "~s is not a bytevector" output-buffer))
-              (error 'make-input/output-port "~s is not a bytevector" input-buffer))
-          (error 'make-input/output-port "~s is not a procedure" handler))))
+  ;(define make-input/output-port
+  ;  (lambda (handler input-buffer output-buffer)
+  ;    (if (procedure? handler)
+  ;        (if (bytevector? input-buffer)
+  ;            (if (bytevector? output-buffer)
+  ;                ($make-input/output-port handler input-buffer output-buffer) 
+  ;                (error 'make-input/output-port "~s is not a bytevector" output-buffer))
+  ;            (error 'make-input/output-port "~s is not a bytevector" input-buffer))
+  ;        (error 'make-input/output-port "~s is not a procedure" handler))))
   ;;;
   (define port-handler
     (lambda (x)
diff --git a/src/makefile.ss b/src/makefile.ss
index 793da9e..1da8a63 100755
--- a/src/makefile.ss
+++ b/src/makefile.ss
@@ -692,8 +692,13 @@
 
     [$make-port/input         $ports]
     [$make-port/output        $ports]
-    [$make-port/both          $ports]
     [$port-handler            $ports]
+    [$port-buffer             $ports]
+    [$port-index              $ports]
+    [$port-size               $ports]
+    [$set-port-index!         $ports]
+    [$set-port-size!          $ports]
+    
     [$port-input-buffer       $ports]
     [$port-input-index        $ports]
     [$port-input-size         $ports]
@@ -705,6 +710,7 @@
     [$set-port-output-index!  $ports]
     [$set-port-output-size!   $ports]
 
+
     [$closure-code            $codes]
     [$code->closure           $codes]
     [$code-reloc-vector       $codes]
diff --git a/src/pass-specify-rep-primops.ss b/src/pass-specify-rep-primops.ss
index 1627996..9cf33c1 100644
--- a/src/pass-specify-rep-primops.ss
+++ b/src/pass-specify-rep-primops.ss
@@ -1424,10 +1424,10 @@
 (define (make-port handler buf/i idx/i sz/i buf/o idx/o sz/o tag)
   (with-tmp ([p (prm 'alloc (K (align port-size)) (K vector-tag))])
     (prm 'mset p (K (- vector-tag)) (K tag))
+    (prm 'mset p (K (- disp-port-buffer vector-tag)) (T buf/i))
+    (prm 'mset p (K (- disp-port-index vector-tag)) (T idx/i))
+    (prm 'mset p (K (- disp-port-size vector-tag)) (T sz/i))
     (prm 'mset p (K (- disp-port-handler vector-tag)) (T handler))
-    (prm 'mset p (K (- disp-port-input-buffer vector-tag)) (T buf/i))
-    (prm 'mset p (K (- disp-port-input-index vector-tag)) (T idx/i))
-    (prm 'mset p (K (- disp-port-input-size vector-tag)) (T sz/i))
     (prm 'mset p (K (- disp-port-output-buffer vector-tag)) (T buf/o))
     (prm 'mset p (K (- disp-port-output-index vector-tag)) (T idx/o))
     (prm 'mset p (K (- disp-port-output-size vector-tag)) (T sz/o))
@@ -1437,48 +1437,55 @@
   [(V handler buf/i idx/i sz/i buf/o idx/o sz/o) 
    (make-port handler buf/i idx/i sz/i buf/o idx/o sz/o
               input-port-tag)])
+
 (define-primop $make-port/output unsafe
   [(V handler buf/i idx/i sz/i buf/o idx/o sz/o) 
    (make-port handler buf/i idx/i sz/i buf/o idx/o sz/o
               output-port-tag)])
-(define-primop $make-port/both unsafe
-  [(V handler buf/i idx/i sz/i buf/o idx/o sz/o) 
-   (make-port handler buf/i idx/i sz/i buf/o idx/o sz/o
-              input/output-port-tag)])
 
 (define-primop $port-handler unsafe
   [(V x) (prm 'mref (T x) (K (- disp-port-handler vector-tag)))])
+(define-primop $port-buffer unsafe
+  [(V x) (prm 'mref (T x) (K (- disp-port-buffer vector-tag)))])
+(define-primop $port-index unsafe
+  [(V x) (prm 'mref (T x) (K (- disp-port-index vector-tag)))])
+(define-primop $port-size unsafe
+  [(V x) (prm 'mref (T x) (K (- disp-port-size vector-tag)))])
+(define-primop $set-port-index! unsafe
+  [(E x i) (prm 'mset (T x) (K (- disp-port-index vector-tag)) (T i))])
+(define-primop $set-port-size! unsafe
+  [(E x i) 
+   (seq*
+     (prm 'mset (T x) (K (- disp-port-index vector-tag)) (K 0))
+     (prm 'mset (T x) (K (- disp-port-size vector-tag)) (T i)))])
+
 (define-primop $port-input-buffer unsafe
-  [(V x) (prm 'mref (T x) (K (- disp-port-input-buffer vector-tag)))])
+  [(V x) (prm 'mref (T x) (K (- disp-port-buffer vector-tag)))])
 (define-primop $port-input-index unsafe
-  [(V x) (prm 'mref (T x) (K (- disp-port-input-index vector-tag)))])
+  [(V x) (prm 'mref (T x) (K (- disp-port-index vector-tag)))])
 (define-primop $port-input-size unsafe
-  [(V x) (prm 'mref (T x) (K (- disp-port-input-size vector-tag)))])
+  [(V x) (prm 'mref (T x) (K (- disp-port-size vector-tag)))])
 (define-primop $port-output-buffer unsafe
   [(V x) (prm 'mref (T x) (K (- disp-port-output-buffer vector-tag)))])
 (define-primop $port-output-index unsafe
   [(V x) (prm 'mref (T x) (K (- disp-port-output-index vector-tag)))])
 (define-primop $port-output-size unsafe
   [(V x) (prm 'mref (T x) (K (- disp-port-output-size vector-tag)))])
-
 (define-primop $set-port-input-index! unsafe
-  [(E x i) (prm 'mset (T x) (K (- disp-port-input-index vector-tag)) (T i))])
+  [(E x i) (prm 'mset (T x) (K (- disp-port-index vector-tag)) (T i))])
 (define-primop $set-port-output-index! unsafe
   [(E x i) (prm 'mset (T x) (K (- disp-port-output-index vector-tag)) (T i))])
-
 (define-primop $set-port-input-size! unsafe
   [(E x i) 
    (seq*
-     (prm 'mset (T x) (K (- disp-port-input-index vector-tag)) (K 0))
-     (prm 'mset (T x) (K (- disp-port-input-size vector-tag)) (T i)))])
+     (prm 'mset (T x) (K (- disp-port-index vector-tag)) (K 0))
+     (prm 'mset (T x) (K (- disp-port-size vector-tag)) (T i)))])
 (define-primop $set-port-output-size! unsafe
   [(E x i) 
    (seq*
      (prm 'mset (T x) (K (- disp-port-output-index vector-tag)) (K 0))
      (prm 'mset (T x) (K (- disp-port-output-size vector-tag)) (T i)))])
 
-
-
 /section)
 
 (section ;;; interrupts-and-engines