ditch the 8-bit compiled form of program parameters

* libguile/vm-i-loader.c (load-program):
* module/system/vm/assemble.scm (dump-object!): There are cases in which
  we use the 16-bit representation for program params (nargs, nexts,
  etc), but the actual 16-bit number actually fits into 8 bits -- which
  is then misinterpreted by the loader as the 8-bit form. So ditch the
  8-bit form entirely (it was never much of an optimization), and just
  use the 16-bit form. Make sure to clear out all your .go files before
  recompiling this one!

diff --git a/libguile/vm-i-loader.c b/libguile/vm-i-loader.c
index 3b232cb..de6f77b 100644 (file)
--- a/libguile/vm-i-loader.c
+++ b/libguile/vm-i-loader.c
@@ -141,25 +141,12 @@ VM_DEFINE_LOADER (load_program, "load-program")
   /* NOTE: format defined in system/vm/assemble.scm */
   if (SCM_I_INUMP (x))
     {
-      int i = SCM_I_INUM (x);
-      if (-128 <= i && i <= 127)
-       {
-          scm_t_uint8 c = (scm_t_uint8)i;
-         /* 8-bit representation */
-         p->nargs = (c >> 6) & 0x03;   /* 7-6 bits */
-         p->nrest = (c >> 5) & 0x01;   /*   5 bit  */
-         p->nlocs = (c >> 2) & 0x07;   /* 4-2 bits */
-         p->nexts = c & 0x03;          /* 1-0 bits */
-       }
-      else
-       {
-          scm_t_uint16 s = (scm_t_uint16)i;
-         /* 16-bit representation */
-         p->nargs = (s >> 12) & 0x0f;  /* 15-12 bits */
-         p->nrest = (s >> 11) & 0x01;  /*    11 bit  */
-         p->nlocs = (s >> 4)  & 0x7f;  /* 10-04 bits */
-         p->nexts = s & 0x0f;          /* 03-00 bits */
-       }
+      scm_t_uint16 s = (scm_t_uint16)SCM_I_INUM (x);
+      /* 16-bit representation */
+      p->nargs = (s >> 12) & 0x0f;     /* 15-12 bits */
+      p->nrest = (s >> 11) & 0x01;     /*    11 bit  */
+      p->nlocs = (s >> 4)  & 0x7f;     /* 10-04 bits */
+      p->nexts = s & 0x0f;             /* 03-00 bits */
     }
   else
     {

diff --git a/module/system/vm/assemble.scm b/module/system/vm/assemble.scm
index aa5f976..6827de6 100644 (file)
--- a/module/system/vm/assemble.scm
+++ b/module/system/vm/assemble.scm
@@ -250,10 +250,6 @@
         (let ((nargs (glil-vars-nargs vars)) (nrest (glil-vars-nrest vars))
               (nlocs (glil-vars-nlocs vars)) (nexts (glil-vars-nexts vars)))
           (cond
-            ((and (< nargs 4) (< nlocs 8) (< nexts 4))
-             ;; 8-bit representation
-             (let ((x (+ (* nargs 64) (* nrest 32) (* nlocs 4) nexts)))
-               (push-code! `(make-int8 ,x))))
             ((and (< nargs 16) (< nlocs 128) (< nexts 16))
              ;; 16-bit representation
              (let ((x (+ (* nargs 4096) (* nrest 2048) (* nlocs 16) nexts)))