Add gc_deactivate / gc_reactivate

Guile needs this.

api/gc-api.h

@@ -53,12 +53,14 @@ GC_API_ void gc_heap_set_extern_space(struct gc_heap *heap,
 GC_API_ struct gc_mutator* gc_init_for_thread(struct gc_stack_addr base,
                                               struct gc_heap *heap);
 GC_API_ void gc_finish_for_thread(struct gc_mutator *mut);
+GC_API_ void gc_deactivate(struct gc_mutator *mut);
+GC_API_ void gc_reactivate(struct gc_mutator *mut);
 GC_API_ void* gc_deactivate_for_call(struct gc_mutator *mut,
                                      void* (*f)(struct gc_mutator*, void*),
-                                     void *data) GC_NEVER_INLINE;
+                                     void *data);
 GC_API_ void* gc_reactivate_for_call(struct gc_mutator *mut,
                                      void* (*f)(struct gc_mutator*, void*),
-                                     void *data) GC_NEVER_INLINE;
+                                     void *data);
 
 GC_API_ void gc_collect(struct gc_mutator *mut,
                         enum gc_collection_kind requested_kind);

src/bdw.c

@@ -668,6 +668,9 @@ static void* call_with_mutator (void *p) {
   return data->proc(data->mutator, data->data);
 }
 
+void gc_deactivate(struct gc_mutator *mut) {};
+void gc_reactivate(struct gc_mutator *mut) {};
+
 void* gc_deactivate_for_call(struct gc_mutator *mut,
                              void* (*f)(struct gc_mutator *, void*),
                              void *data) {

src/mmc.c

@@ -1297,6 +1297,16 @@ reactivate_mutator(struct gc_heap *heap, struct gc_mutator *mut) {
   heap_unlock(heap);
 }
 
+void gc_deactivate(struct gc_mutator *mut) {
+  GC_ASSERT(mut->active);
+  deactivate_mutator(mutator_heap(mut), mut);
+}
+
+void gc_reactivate(struct gc_mutator *mut) {
+  GC_ASSERT(!mut->active);
+  reactivate_mutator(mutator_heap(mut), mut);
+}
+
 void*
 gc_deactivate_for_call(struct gc_mutator *mut,
                        void* (*f)(struct gc_mutator*, void*),

src/pcc.c

@@ -1383,6 +1383,16 @@ static void reactivate_mutator(struct gc_heap *heap, struct gc_mutator *mut) {
   heap_unlock(heap);
 }
 
+void gc_deactivate(struct gc_mutator *mut) {
+  GC_ASSERT(mut->active);
+  deactivate_mutator(mutator_heap(mut), mut);
+}
+
+void gc_reactivate(struct gc_mutator *mut) {
+  GC_ASSERT(!mut->active);
+  reactivate_mutator(mutator_heap(mut), mut);
+}
+
 void* gc_deactivate_for_call(struct gc_mutator *mut,
                              void* (*f)(struct gc_mutator*, void*),
                              void *data) {

src/semi.c

@@ -763,6 +763,10 @@ struct gc_mutator* gc_init_for_thread(struct gc_stack_addr base,
 void gc_finish_for_thread(struct gc_mutator *space) {
 }
 
+void gc_deactivate(struct gc_mutator *mut) {}
+
+void gc_reactivate(struct gc_mutator *mut) {}
+
 void* gc_deactivate_for_call(struct gc_mutator *mut,
                              void* (*f)(struct gc_mutator *, void*),
                              void *data) {