Remove the restore-continuation-hook.

* libguile/vm.h:
* libguile/vm.c:
* libguile/vm-engine.c:
* module/system/vm/traps.scm:
* module/system/vm/vm.scm: Remove the unused and redundant
  restore-continuation-hook.

libguile/vm-engine.c

@@ -125,8 +125,6 @@
   RUN_HOOK0 (next)
 #define ABORT_CONTINUATION_HOOK()               \
   RUN_HOOK0 (abort)
-#define RESTORE_CONTINUATION_HOOK()             \
-  RUN_HOOK0 (restore_continuation)
 
 #define VM_HANDLE_INTERRUPTS                     \
   SCM_ASYNC_TICK_WITH_GUARD_CODE (current_thread, SYNC_IP (), CACHE_FP ())
@@ -3228,7 +3226,6 @@ VM_NAME (scm_i_thread *current_thread, struct scm_vm *vp,
 #undef NEXT_JUMP
 #undef POP_CONTINUATION_HOOK
 #undef PUSH_CONTINUATION_HOOK
-#undef RESTORE_CONTINUATION_HOOK
 #undef RETURN
 #undef RETURN_ONE_VALUE
 #undef RETURN_VALUE_LIST

libguile/vm.c

@@ -167,7 +167,6 @@ static void vm_dispatch_push_continuation_hook (struct scm_vm *vp) SCM_NOINLINE;
 static void vm_dispatch_pop_continuation_hook (struct scm_vm *vp, SCM *old_fp) SCM_NOINLINE;
 static void vm_dispatch_next_hook (struct scm_vm *vp) SCM_NOINLINE;
 static void vm_dispatch_abort_hook (struct scm_vm *vp) SCM_NOINLINE;
-static void vm_dispatch_restore_continuation_hook (struct scm_vm *vp) SCM_NOINLINE;
 
 static void
 vm_dispatch_hook (struct scm_vm *vp, int hook_num, SCM *argv, int n)
@@ -258,10 +257,6 @@ static void vm_dispatch_abort_hook (struct scm_vm *vp)
                            &SCM_FRAME_LOCAL (vp->fp, 1),
                            SCM_FRAME_NUM_LOCALS (vp->fp, vp->sp) - 1);
 }
-static void vm_dispatch_restore_continuation_hook (struct scm_vm *vp)
-{
-  return vm_dispatch_hook (vp, SCM_VM_RESTORE_CONTINUATION_HOOK, NULL, 0);
-}
 
 static void
 vm_abort (struct scm_vm *vp, SCM tag,
@@ -1025,15 +1020,6 @@ SCM_DEFINE (scm_vm_abort_continuation_hook, "vm-abort-continuation-hook", 0, 0,
 }
 #undef FUNC_NAME
 
-SCM_DEFINE (scm_vm_restore_continuation_hook, "vm-restore-continuation-hook", 0, 0, 0,
-	    (void),
-	    "")
-#define FUNC_NAME s_scm_vm_restore_continuation_hook
-{
-  VM_DEFINE_HOOK (SCM_VM_RESTORE_CONTINUATION_HOOK);
-}
-#undef FUNC_NAME
-
 SCM_DEFINE (scm_vm_trace_level, "vm-trace-level", 0, 0, 0,
 	    (void),
 	    "")

libguile/vm.h

@@ -28,7 +28,6 @@ enum {
   SCM_VM_POP_CONTINUATION_HOOK,
   SCM_VM_NEXT_HOOK,
   SCM_VM_ABORT_CONTINUATION_HOOK,
-  SCM_VM_RESTORE_CONTINUATION_HOOK,
   SCM_VM_NUM_HOOKS,
 };
 
@@ -56,7 +55,6 @@ SCM_API SCM scm_vm_apply_hook (void);
 SCM_API SCM scm_vm_push_continuation_hook (void);
 SCM_API SCM scm_vm_pop_continuation_hook (void);
 SCM_API SCM scm_vm_abort_continuation_hook (void);
-SCM_API SCM scm_vm_restore_continuation_hook (void);
 SCM_API SCM scm_vm_next_hook (void);
 SCM_API SCM scm_vm_trace_level (void);
 SCM_API SCM scm_set_vm_trace_level_x (SCM level);

module/system/vm/traps.scm

@@ -199,12 +199,6 @@
       (if (our-frame? frame)
           (enter-proc frame)))
 
-    (define (restore-hook frame)
-      (if in-proc?
-          (exit-proc frame))
-      (if (our-frame? frame)
-          (enter-proc frame)))
-
     (new-enabled-trap
      current-frame
      (lambda (frame)
@@ -212,7 +206,6 @@
        (add-hook! (vm-push-continuation-hook) push-cont-hook)
        (add-hook! (vm-pop-continuation-hook) pop-cont-hook)
        (add-hook! (vm-abort-continuation-hook) abort-hook)
-       (add-hook! (vm-restore-continuation-hook) restore-hook)
        (if (and frame (our-frame? frame))
            (enter-proc frame)))
      (lambda (frame)
@@ -221,8 +214,7 @@
        (remove-hook! (vm-apply-hook) apply-hook)
        (remove-hook! (vm-push-continuation-hook) push-cont-hook)
        (remove-hook! (vm-pop-continuation-hook) pop-cont-hook)
-       (remove-hook! (vm-abort-continuation-hook) abort-hook)
+       (remove-hook! (vm-abort-continuation-hook) abort-hook)))))
-       (remove-hook! (vm-restore-continuation-hook) restore-hook)))))
 
 ;; Building on trap-in-procedure, we have trap-instructions-in-procedure
 ;;
@@ -425,13 +417,11 @@
        (if (not fp)
            (error "return-or-abort traps may only be enabled once"))
        (add-hook! (vm-pop-continuation-hook) pop-cont-hook)
-       (add-hook! (vm-abort-continuation-hook) abort-hook)
+       (add-hook! (vm-abort-continuation-hook) abort-hook))
-       (add-hook! (vm-restore-continuation-hook) abort-hook))
      (lambda (frame)
        (set! fp #f)
        (remove-hook! (vm-pop-continuation-hook) pop-cont-hook)
-       (remove-hook! (vm-abort-continuation-hook) abort-hook)
+       (remove-hook! (vm-abort-continuation-hook) abort-hook)))))
-       (remove-hook! (vm-restore-continuation-hook) abort-hook)))))
 
 ;; A more traditional dynamic-wind trap. Perhaps this should not be
 ;; based on the above trap-frame-finish?

module/system/vm/vm.scm

@@ -25,7 +25,7 @@
             vm-push-continuation-hook vm-pop-continuation-hook
             vm-apply-hook
             vm-next-hook
-            vm-abort-continuation-hook vm-restore-continuation-hook))
+            vm-abort-continuation-hook))
 
 (load-extension (string-append "libguile-" (effective-version))
                 "scm_init_vm")