Remove MVRA accessors in libguile

* libguile/vm.c (scm_i_vm_capture_stack): Remove MVRA argument, in
  preparation for removing MVRA from frames.
  (scm_i_capture_current_stack): Adapt to scm_i_vm_capture_stack
  change.
  (vm_reinstate_partial_continuation): Remove references to MVRA.

* libguile/vm.h (struct scm_vm_cont): Remove mvra member.

* libguile/vm-engine.c (call): Set MVRA to 0.  Will remove later.
  (return-values): Return to RA.
  (call/cc): Remove MVRA from capture call.

* libguile/frames.c:
* libguile/frames.h (SCM_FRAME_MV_RETURN_ADDRESS)
  (SCM_FRAME_RTL_MV_RETURN_ADDRESS, scm_frame_mv_return_address): Remove
  accessors.

* libguile/control.c (reify_partial_continuation): Adapt to
  scm_i_vm_capture_stack change.

libguile/control.c

@@ -108,12 +108,10 @@ reify_partial_continuation (SCM vm,
   if (SCM_FRAME_DYNAMIC_LINK (bottom_fp) != saved_fp)
     abort();
 
-  /* Capture from the top of the thunk application frame up to the end. Set an
+  /* Capture from the top of the thunk application frame up to the end. */
-     MVRA only, as the post-abort code is in an MV context. */
   vm_cont = scm_i_vm_capture_stack (bottom_fp - 1,
                                     SCM_VM_DATA (vm)->fp,
                                     SCM_VM_DATA (vm)->sp,
-                                    NULL,
                                     SCM_VM_DATA (vm)->ip,
                                     dynstack,
                                     flags);

libguile/frames.c

@@ -245,18 +245,6 @@ SCM_DEFINE (scm_frame_return_address, "frame-return-address", 1, 0, 0,
 }
 #undef FUNC_NAME
 
-SCM_DEFINE (scm_frame_mv_return_address, "frame-mv-return-address", 1, 0, 0,
-	    (SCM frame),
-	    "")
-#define FUNC_NAME s_scm_frame_mv_return_address
-{
-  SCM_VALIDATE_VM_FRAME (1, frame);
-  return scm_from_uintptr_t ((scm_t_uintptr)
-                             (SCM_FRAME_MV_RETURN_ADDRESS
-                              (SCM_VM_FRAME_FP (frame))));
-}
-#undef FUNC_NAME
-
 SCM_DEFINE (scm_frame_dynamic_link, "frame-dynamic-link", 1, 0, 0,
 	    (SCM frame),
 	    "")

libguile/frames.h

@@ -1,4 +1,4 @@
-/* Copyright (C) 2001, 2009, 2010, 2011, 2012 Free Software Foundation, Inc.
+/* Copyright (C) 2001, 2009, 2010, 2011, 2012, 2013 Free Software Foundation, Inc.
  * * 
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Lesser General Public License
@@ -85,8 +85,6 @@ struct scm_vm_frame
   (SCM_FRAME_STRUCT (fp)->return_address)
 #define SCM_FRAME_SET_RETURN_ADDRESS(fp, ra)    \
   SCM_FRAME_STRUCT (fp)->return_address = (ra)
-#define SCM_FRAME_MV_RETURN_ADDRESS(fp)         \
-  (SCM_FRAME_STRUCT (fp)->mv_return_address)
 #define SCM_FRAME_SET_MV_RETURN_ADDRESS(fp, mvra)       \
   SCM_FRAME_STRUCT (fp)->mv_return_address = (mvra)
 #define SCM_FRAME_DYNAMIC_LINK(fp)              \
@@ -124,8 +122,6 @@ struct scm_vm_frame
 #define SCM_FRAME_SET_RTL_RETURN_ADDRESS(fp, ip)        \
   SCM_FRAME_SET_RETURN_ADDRESS (fp, (scm_t_uint8 *) (ip))
 
-#define SCM_FRAME_RTL_MV_RETURN_ADDRESS(fp)             \
-  ((scm_t_uint32 *) SCM_FRAME_MV_RETURN_ADDRESS (fp))
 #define SCM_FRAME_SET_RTL_MV_RETURN_ADDRESS(fp, ip)     \
   SCM_FRAME_SET_MV_RETURN_ADDRESS (fp, (scm_t_uint8 *) (ip))
 
@@ -165,7 +161,6 @@ SCM_API SCM scm_frame_address (SCM frame);
 SCM_API SCM scm_frame_stack_pointer (SCM frame);
 SCM_API SCM scm_frame_instruction_pointer (SCM frame);
 SCM_API SCM scm_frame_return_address (SCM frame);
-SCM_API SCM scm_frame_mv_return_address (SCM frame);
 SCM_API SCM scm_frame_dynamic_link (SCM frame);
 SCM_API SCM scm_frame_previous (SCM frame);
 

libguile/vm-engine.c

@@ -574,7 +574,7 @@ RTL_VM_NAME (SCM vm, SCM program, SCM *argv, size_t nargs_)
 
       fp = vp->fp = old_fp + proc;
       SCM_FRAME_SET_DYNAMIC_LINK (fp, old_fp);
-      SCM_FRAME_SET_RTL_MV_RETURN_ADDRESS (fp, ip + 2);
+      SCM_FRAME_SET_RTL_MV_RETURN_ADDRESS (fp, 0);
       SCM_FRAME_SET_RTL_RETURN_ADDRESS (fp, ip + 2);
 
       RESET_FRAME (nlocals);
@@ -711,7 +711,7 @@ RTL_VM_NAME (SCM vm, SCM program, SCM *argv, size_t nargs_)
       SCM *base = fp;
 
       VM_HANDLE_INTERRUPTS;
-      ip = SCM_FRAME_RTL_MV_RETURN_ADDRESS (fp);
+      ip = SCM_FRAME_RTL_RETURN_ADDRESS (fp);
       fp = vp->fp = SCM_FRAME_DYNAMIC_LINK (fp);
 
       /* Clear stack frame.  */
@@ -954,7 +954,6 @@ RTL_VM_NAME (SCM vm, SCM program, SCM *argv, size_t nargs_)
                                         SCM_FRAME_DYNAMIC_LINK (fp),
                                         SCM_FRAME_LOWER_ADDRESS (fp) - 1,
                                         SCM_FRAME_RETURN_ADDRESS (fp),
-                                        SCM_FRAME_MV_RETURN_ADDRESS (fp),
                                         dynstack,
                                         0);
       /* FIXME: Seems silly to capture the registers here, when they are

libguile/vm.c

@@ -104,8 +104,7 @@ scm_i_vm_cont_print (SCM x, SCM port, scm_print_state *pstate)
  */
 SCM
 scm_i_vm_capture_stack (SCM *stack_base, SCM *fp, SCM *sp, scm_t_uint8 *ra,
-                        scm_t_uint8 *mvra, scm_t_dynstack *dynstack,
+                        scm_t_dynstack *dynstack, scm_t_uint32 flags)
-                        scm_t_uint32 flags)
 {
   struct scm_vm_cont *p;
 
@@ -123,7 +122,6 @@ scm_i_vm_capture_stack (SCM *stack_base, SCM *fp, SCM *sp, scm_t_uint8 *ra,
   memset (p->stack_base, 0, p->stack_size * sizeof (SCM));
 #endif
   p->ra = ra;
-  p->mvra = mvra;
   p->sp = sp;
   p->fp = fp;
   memcpy (p->stack_base, stack_base, (sp + 1 - stack_base) * sizeof (SCM));
@@ -146,10 +144,6 @@ vm_return_to_continuation (SCM vm, SCM cont, size_t n, SCM *argv)
   vp = SCM_VM_DATA (vm);
   cp = SCM_VM_CONT_DATA (cont);
 
-  if (n == 0 && !cp->mvra)
-    scm_misc_error (NULL, "Too few values returned to continuation",
-                    SCM_EOL);
-
   if (vp->stack_size < cp->stack_size + n + 4)
     scm_misc_error ("vm-engine", "not enough space to reinstate continuation",
                     scm_list_2 (vm, cont));
@@ -183,7 +177,7 @@ vm_return_to_continuation (SCM vm, SCM cont, size_t n, SCM *argv)
         vp->sp++;
         *vp->sp = argv_copy[i];
       }
-    vp->ip = cp->mvra;
+    vp->ip = cp->ra;
   }
 }
 
@@ -198,7 +192,7 @@ scm_i_capture_current_stack (void)
   vm = scm_the_vm ();
   vp = SCM_VM_DATA (vm);
 
-  return scm_i_vm_capture_stack (vp->stack_base, vp->fp, vp->sp, vp->ip, NULL,
+  return scm_i_vm_capture_stack (vp->stack_base, vp->fp, vp->sp, vp->ip,
                                  scm_dynstack_capture_all (&thread->dynstack),
                                  0);
 }
@@ -342,19 +336,14 @@ vm_reinstate_partial_continuation (SCM vm, SCM cont, size_t n, SCM *argv,
 
   vp->sp = base - 1 + cp->stack_size;
   vp->fp = RELOC (cp->fp);
-  vp->ip = cp->mvra;
+  vp->ip = cp->ra;
 
-  /* now push args. ip is in a MV context. */
+  /* Push the arguments. */
   for (i = 0; i < n; i++)
     {
       vp->sp++;
       *vp->sp = argv_copy[i];
     }
-#if 0
-  /* The number-of-values marker, only used by the stack VM.  */
-  vp->sp++;
-  *vp->sp = scm_from_size_t (n);
-#endif
 
   /* The prompt captured a slice of the dynamic stack.  Here we wind
      those entries onto the current thread's stack.  We also have to

libguile/vm.h

@@ -88,7 +88,7 @@ SCM_API void scm_c_set_default_vm_engine_x (int engine);
 struct scm_vm_cont {
   SCM *sp;
   SCM *fp;
-  scm_t_uint8 *ra, *mvra;
+  scm_t_uint8 *ra;
   scm_t_ptrdiff stack_size;
   SCM *stack_base;
   scm_t_ptrdiff reloc;
@@ -110,7 +110,7 @@ SCM_INTERNAL void scm_i_vm_print (SCM x, SCM port,
 SCM_INTERNAL SCM scm_i_call_with_current_continuation (SCM proc);
 SCM_INTERNAL SCM scm_i_capture_current_stack (void);
 SCM_INTERNAL SCM scm_i_vm_capture_stack (SCM *stack_base, SCM *fp, SCM *sp,
-                                         scm_t_uint8 *ra, scm_t_uint8 *mvra,
+                                         scm_t_uint8 *ra,
                                          scm_t_dynstack *dynstack,
                                          scm_t_uint32 flags);
 SCM_INTERNAL void scm_i_vm_cont_print (SCM x, SCM port,