rt: Make the box annihilator walk and delete contents

src/rt/rust_box_annihilator.cpp

@@ -1,6 +1,198 @@
 #include "rust_internal.h"
 #include "rust_shape.h"
 
+class annihilator : public shape::data<annihilator,shape::ptr> {
+    friend class shape::data<annihilator,shape::ptr>;
+
+    annihilator(const annihilator &other, const shape::ptr &in_dp)
+        : shape::data<annihilator,shape::ptr>(other.task, other.align,
+                                        other.sp, other.params,
+                                        other.tables, in_dp) {}
+
+    annihilator(const annihilator &other,
+          const uint8_t *in_sp,
+          const shape::type_param *in_params,
+          const rust_shape_tables *in_tables = NULL)
+        : shape::data<annihilator,shape::ptr>(other.task,
+                                        other.align,
+                                        in_sp,
+                                        in_params,
+                                        in_tables ? in_tables : other.tables,
+                                        other.dp) {}
+
+    annihilator(const annihilator &other,
+          const uint8_t *in_sp,
+          const shape::type_param *in_params,
+          const rust_shape_tables *in_tables,
+          shape::ptr in_dp)
+        : shape::data<annihilator,shape::ptr>(other.task,
+                                        other.align,
+                                        in_sp,
+                                        in_params,
+                                        in_tables,
+                                        in_dp) {}
+
+    annihilator(rust_task *in_task,
+          bool in_align,
+          const uint8_t *in_sp,
+          const shape::type_param *in_params,
+          const rust_shape_tables *in_tables,
+          uint8_t *in_data)
+        : shape::data<annihilator,shape::ptr>(in_task, in_align, in_sp,
+                                        in_params, in_tables, in_data) {}
+
+    void walk_vec2(bool is_pod, uint16_t sp_size) {
+        void *vec = shape::get_dp<void *>(dp);
+        walk_vec2(is_pod, get_vec_data_range(dp));
+        task->kernel->free(vec);
+    }
+
+    void walk_vec2(bool is_pod,
+                  const std::pair<shape::ptr,shape::ptr> &data_range) {
+        annihilator sub(*this, data_range.first);
+        shape::ptr data_end = sub.end_dp = data_range.second;
+        while (sub.dp < data_end) {
+            sub.walk_reset();
+            sub.align = true;
+        }
+    }
+
+    void walk_tag2(shape::tag_info &tinfo, uint32_t tag_variant) {
+        shape::data<annihilator,shape::ptr>::walk_variant1(tinfo, tag_variant);
+    }
+
+    void walk_uniq2() {
+        void *x = *((void **)dp);
+        // free contents first:
+        shape::data<annihilator,shape::ptr>::walk_uniq_contents1();
+        // now free the ptr:
+        task->kernel->free(x);
+    }
+
+    void walk_box2() {
+        // In annihilator phase, do not walk the box contents.  There is an
+        // outer loop walking all remaining boxes, and this box may well
+        // have been freed already!
+    }
+
+    void walk_fn2(char code) {
+        switch (code) {
+          case shape::SHAPE_UNIQ_FN: {
+              fn_env_pair pair = *(fn_env_pair*)dp;
+
+              if (pair.env) {
+                  // free closed over data:
+                  shape::data<annihilator,shape::ptr>::walk_fn_contents1();
+                  
+                  // now free the ptr:
+                  task->kernel->free(pair.env);
+              }
+              break;
+          }
+          case shape::SHAPE_BOX_FN: {
+              // the box will be visited separately:
+              shape::bump_dp<void*>(dp); // skip over the code ptr
+              walk_box2();               // walk over the environment ptr
+              break;
+          }
+          case shape::SHAPE_BARE_FN:         // Does not close over data.
+          case shape::SHAPE_STACK_FN: break; // Not reachable from heap.
+          default: abort();
+        }
+    }
+
+    void walk_obj2() {
+        return;
+    }
+
+    void walk_iface2() {
+        walk_box2();
+    }
+
+    void walk_tydesc2(char kind) {
+        switch(kind) {
+          case shape::SHAPE_TYDESC:
+          case shape::SHAPE_SEND_TYDESC:
+            break;
+          default: abort();
+        }
+    }
+
+    struct run_dtor_args {
+        const shape::rust_fn *dtor;
+        void *data;
+    };
+
+    typedef void (*dtor)(void **retptr, void *env, void *dptr);
+
+    static void run_dtor(run_dtor_args *args) {
+        dtor f = (dtor)args->dtor;
+        f(NULL, args->dtor->env, args->data);
+    }
+
+    void walk_res2(const shape::rust_fn *dtor, unsigned n_params,
+                   const shape::type_param *params, const uint8_t *end_sp,
+                   bool live) {
+        void *data = (void*)(uintptr_t)dp;
+        // Switch back to the Rust stack to run the destructor
+        run_dtor_args args = {dtor, data};
+        task->call_on_rust_stack((void*)&args, (void*)run_dtor);
+
+        while (this->sp != end_sp) {
+            this->walk();
+            align = true;
+        }
+    }
+
+    void walk_subcontext2(annihilator &sub) { sub.walk(); }
+
+    void walk_uniq_contents2(annihilator &sub) { sub.walk(); }
+
+    void walk_struct2(const uint8_t *end_sp) {
+        while (this->sp != end_sp) {
+            this->walk();
+            align = true;
+        }
+    }
+
+    void walk_variant2(shape::tag_info &tinfo, uint32_t variant_id,
+                      const std::pair<const uint8_t *,const uint8_t *>
+                      variant_ptr_and_end) {
+        annihilator sub(*this, variant_ptr_and_end.first, tinfo.params);
+
+        const uint8_t *variant_end = variant_ptr_and_end.second;
+        while (sub.sp < variant_end) {
+            sub.walk();
+            align = true;
+        }
+    }
+
+    template<typename T>
+    inline void walk_number2() { /* no-op */ }
+
+public:
+    static void do_annihilate(rust_task *task, rust_opaque_box *box);
+};
+
+void
+annihilator::do_annihilate(rust_task *task, rust_opaque_box *box) {
+    const type_desc *tydesc = box->td;
+    uint8_t *p = (uint8_t*) box_body(box);
+    shape::arena arena;
+    shape::type_param *params =
+        shape::type_param::from_tydesc_and_data(tydesc, p, arena);
+
+    annihilator annihilator(task, true, tydesc->shape,
+                            params, tydesc->shape_tables, p);
+    annihilator.walk();
+    task->boxed.free(box);
+}
+
+void
+annihilate_box(rust_task *task, rust_opaque_box *box) {
+    annihilator::do_annihilate(task, box);
+}
+
 void
 annihilate_boxes(rust_task *task) {
     LOG(task, gc, "annihilating boxes for task %p", task);
@@ -10,6 +202,7 @@ annihilate_boxes(rust_task *task) {
     while (box != NULL) {
         rust_opaque_box *tmp = box;
         box = box->next;
-        boxed->free(tmp);
+        annihilate_box(task, tmp);
     }
 }
+