Disable f64->scm instruction

* libguile/vm-engine.c (f64->scm): Disable instruction.
* module/language/cps/compile-bytecode.scm (compile-function): Remove
  f64->scm case.
* module/system/vm/assembler.scm: Remove emit-f64->scm export.

libguile/vm-engine.c

@@ -2244,12 +2244,7 @@ VM_NAME (scm_i_thread *thread, struct scm_vm *vp,
       NEXT (1);
     }
 
-  /* f64->scm dst:12 src:12
-   *
-   * Pack a raw double-precision floating point value into an inexact
-   * number allocated on the heap.
-   */
-  VM_DEFINE_OP (137, f64_to_scm, "f64->scm", OP1 (X8_S12_S12) | OP_DST)
+  VM_DEFINE_OP (137, unused_137, NULL, NOP)
     {
       scm_t_uint16 dst, src;
       UNPACK_12_12 (op, dst, src);

module/language/cps/compile-bytecode.scm

@@ -205,8 +205,6 @@
          (emit-scm->f64 asm (from-sp dst) (from-sp (slot src))))
         (($ $primcall 'load-f64 val ())
          (emit-load-f64 asm (from-sp dst) val))
-        (($ $primcall 'f64->scm #f (src))
-         (emit-f64->scm asm (from-sp dst) (from-sp (slot src))))
         (($ $primcall 'scm->u64 #f (src))
          (emit-scm->u64 asm (from-sp dst) (from-sp (slot src))))
         (($ $primcall 'scm->u64/truncate #f (src))

module/system/vm/assembler.scm

@@ -263,7 +263,6 @@
             emit-ulsh/immediate
             emit-make-array
             emit-load-f64
-            emit-f64->scm
             emit-scm->u64
             emit-scm->u64/truncate
             emit-load-u64