diff --git a/vm_core.h b/vm_core.h
index 6c933afdcc..1339007f2a 100644
--- a/vm_core.h
+++ b/vm_core.h
@@ -1719,9 +1719,9 @@ struct rb_trace_arg_struct {
 
 void rb_exec_event_hooks(struct rb_trace_arg_struct *trace_arg, int pop_p);
 
-#define EXEC_EVENT_HOOK_ORIG(ec_, flag_, self_, id_, called_id_, klass_, data_, pop_p_) do { \
+#define EXEC_EVENT_HOOK_ORIG(ec_, flag_, vm_flags_, self_, id_, called_id_, klass_, data_, pop_p_) do { \
     const rb_event_flag_t flag_arg_ = (flag_); \
-    if (UNLIKELY(ruby_vm_event_flags & (flag_arg_))) { \
+    if (UNLIKELY(vm_flags_ & (flag_arg_))) { \
 	/* defer evaluating the other arguments */ \
 	rb_exec_event_hook_orig(ec_, flag_arg_, self_, id_, called_id_, klass_, data_, pop_p_); \
     } \
@@ -1731,29 +1731,32 @@ static inline void
 rb_exec_event_hook_orig(rb_execution_context_t *ec, const rb_event_flag_t flag,
 			VALUE self, ID id, ID called_id, VALUE klass, VALUE data, int pop_p)
 {
-    const rb_vm_t *vm = rb_ec_vm_ptr(ec);
+    struct rb_trace_arg_struct trace_arg;
 
-    if (vm->event_hooks.events & flag) {
-	struct rb_trace_arg_struct trace_arg;
-	trace_arg.event = flag;
-	trace_arg.ec = ec;
-	trace_arg.cfp = ec->cfp;
-	trace_arg.self = self;
-	trace_arg.id = id;
-	trace_arg.called_id = called_id;
-	trace_arg.klass = klass;
-	trace_arg.data = data;
-	trace_arg.path = Qundef;
-	trace_arg.klass_solved = 0;
-	rb_exec_event_hooks(&trace_arg, pop_p);
-    }
+    VM_ASSERT(rb_ec_vm_ptr(ec)->event_hooks.events == ruby_vm_event_flags);
+    VM_ASSERT(rb_ec_vm_ptr(ec)->event_hooks.events & flag);
+
+    trace_arg.event = flag;
+    trace_arg.ec = ec;
+    trace_arg.cfp = ec->cfp;
+    trace_arg.self = self;
+    trace_arg.id = id;
+    trace_arg.called_id = called_id;
+    trace_arg.klass = klass;
+    trace_arg.data = data;
+    trace_arg.path = Qundef;
+    trace_arg.klass_solved = 0;
+    rb_exec_event_hooks(&trace_arg, pop_p);
 }
 
 #define EXEC_EVENT_HOOK(ec_, flag_, self_, id_, called_id_, klass_, data_) \
-  EXEC_EVENT_HOOK_ORIG(ec_, flag_, self_, id_, called_id_, klass_, data_, 0)
+  EXEC_EVENT_HOOK_ORIG(ec_, flag_, ruby_vm_event_flags, self_, id_, called_id_, klass_, data_, 0)
+
+#define EXEC_EVENT_HOOK_VM_TRACE(ec_, flag_, vm_flag_, self_, id_, called_id_, klass_, data_) \
+  EXEC_EVENT_HOOK_ORIG(ec_, flag_, vm_flag_, self_, id_, called_id_, klass_, data_, 0)
 
 #define EXEC_EVENT_HOOK_AND_POP_FRAME(ec_, flag_, self_, id_, called_id_, klass_, data_) \
-  EXEC_EVENT_HOOK_ORIG(ec_, flag_, self_, id_, called_id_, klass_, data_, 1)
+  EXEC_EVENT_HOOK_ORIG(ec_, flag_, ruby_vm_event_flags, self_, id_, called_id_, klass_, data_, 1)
 
 RUBY_SYMBOL_EXPORT_BEGIN
 
diff --git a/vm_insnhelper.c b/vm_insnhelper.c
index b172c2d20f..5340405236 100644
--- a/vm_insnhelper.c
+++ b/vm_insnhelper.c
@@ -3729,13 +3729,13 @@ vm_trace(rb_execution_context_t *ec, rb_control_frame_t *reg_cfp, const VALUE *p
 {
     const rb_iseq_t *iseq = reg_cfp->iseq;
     size_t pos = pc - iseq->body->iseq_encoded;
-    rb_event_flag_t cur_event_flags = ruby_vm_event_flags;
+    rb_event_flag_t vm_event_flags = ruby_vm_event_flags;
     rb_event_flag_t events = rb_iseq_event_flags(iseq, pos);
     rb_event_flag_t event;
 
-    if ((events & cur_event_flags) == 0) {
+    if ((events & vm_event_flags) == 0) {
 	/* disable trace */
-	rb_iseq_trace_set(iseq, cur_event_flags);
+	rb_iseq_trace_set(iseq, vm_event_flags);
 	return;
     }
 
@@ -3752,32 +3752,31 @@ vm_trace(rb_execution_context_t *ec, rb_control_frame_t *reg_cfp, const VALUE *p
 
     VM_ASSERT(reg_cfp->pc == pc);
     VM_ASSERT(events != 0);
+    VM_ASSERT(vm_event_flags & events);
 
     /* increment PC because source line is calculated with PC-1 */
-    if (events & ruby_vm_event_flags) {
-	if (event = (events & (RUBY_EVENT_CLASS | RUBY_EVENT_CALL | RUBY_EVENT_B_CALL))) {
-	    VM_ASSERT(event == RUBY_EVENT_CLASS ||
-		      event == RUBY_EVENT_CALL  ||
-		      event == RUBY_EVENT_B_CALL);
-	    reg_cfp->pc++;
-	    vm_dtrace(event, ec);
-	    EXEC_EVENT_HOOK(ec, event, GET_SELF(), 0, 0, 0, Qundef);
-	    reg_cfp->pc--;
-	}
-	if (events & RUBY_EVENT_LINE) {
-	    reg_cfp->pc++;
-	    vm_dtrace(RUBY_EVENT_LINE, ec);
-	    EXEC_EVENT_HOOK(ec, RUBY_EVENT_LINE, GET_SELF(), 0, 0, 0, Qundef);
-	    reg_cfp->pc--;
-	}
-	if (event = (events & (RUBY_EVENT_END | RUBY_EVENT_RETURN | RUBY_EVENT_B_RETURN))) {
-	    VM_ASSERT(event == RUBY_EVENT_END ||
-		      event == RUBY_EVENT_RETURN  ||
-		      event == RUBY_EVENT_B_RETURN);
-	    reg_cfp->pc++;
-	    vm_dtrace(RUBY_EVENT_LINE, ec);
-	    EXEC_EVENT_HOOK(ec, event, GET_SELF(), 0, 0, 0, TOPN(0));
-	    reg_cfp->pc--;
-	}
+    if (event = (events & (RUBY_EVENT_CLASS | RUBY_EVENT_CALL | RUBY_EVENT_B_CALL))) {
+	VM_ASSERT(event == RUBY_EVENT_CLASS ||
+		  event == RUBY_EVENT_CALL  ||
+		  event == RUBY_EVENT_B_CALL);
+	reg_cfp->pc++;
+	vm_dtrace(event, ec);
+	EXEC_EVENT_HOOK_VM_TRACE(ec, event, vm_event_flags, GET_SELF(), 0, 0, 0, Qundef);
+	reg_cfp->pc--;
+    }
+    if (events & RUBY_EVENT_LINE) {
+	reg_cfp->pc++;
+	vm_dtrace(RUBY_EVENT_LINE, ec);
+	EXEC_EVENT_HOOK_VM_TRACE(ec, RUBY_EVENT_LINE, vm_event_flags, GET_SELF(), 0, 0, 0, Qundef);
+	reg_cfp->pc--;
+    }
+    if (event = (events & (RUBY_EVENT_END | RUBY_EVENT_RETURN | RUBY_EVENT_B_RETURN))) {
+	VM_ASSERT(event == RUBY_EVENT_END ||
+		  event == RUBY_EVENT_RETURN  ||
+		  event == RUBY_EVENT_B_RETURN);
+	reg_cfp->pc++;
+	vm_dtrace(RUBY_EVENT_LINE, ec);
+	EXEC_EVENT_HOOK_VM_TRACE(ec, event, vm_event_flags, GET_SELF(), 0, 0, 0, TOPN(0));
+	reg_cfp->pc--;
     }
 }