Implement GC stack object tracking for func object

core/iwasm/common/gc/gc_object.c

@@ -290,15 +290,24 @@ wasm_array_obj_get_elem(WASMArrayObjectRef array_obj, uint32 elem_idx,
 
 WASMFuncObjectRef
 wasm_func_obj_new(void *heap_handle, WASMRttObjectRef rtt_obj,
-                  uint32 func_idx_bound, uint32 param_count_bound)
+                  const WASMFuncType *func_type_bound, uint32 func_idx_bound,
+                  uint32 param_count_bound)
 {
     WASMFuncObjectRef func_obj;
     uint64 total_size;
+    uint32 ref_param_count = 0, offset = 0, i;
+    uint16 *reference_table;
 
     bh_assert(rtt_obj->type_flag == WASM_TYPE_FUNC);
 
+    for (i = 0; i < param_count_bound; i++) {
+        if (wasm_is_type_reftype(func_type_bound->types[i]))
+            ref_param_count++;
+    }
+
     total_size = offsetof(WASMFuncObject, params_bound)
-                 + (uint64)sizeof(WASMValue) * param_count_bound;
+                 + (uint64)sizeof(WASMValue) * param_count_bound
+                 + (uint64)sizeof(uint16) * (ref_param_count + 1);
     if (!(func_obj = gc_obj_malloc(heap_handle, total_size))) {
         return NULL;
     }
@@ -306,6 +315,18 @@ wasm_func_obj_new(void *heap_handle, WASMRttObjectRef rtt_obj,
     func_obj->header = (WASMObjectHeader)rtt_obj;
     func_obj->func_idx_bound = func_idx_bound;
     func_obj->param_count_bound = param_count_bound;
+    func_obj->reference_table = reference_table =
+        (uint16 *)((uint8 *)func_obj + offsetof(WASMFuncObject, params_bound)
+                   + sizeof(WASMValue) * param_count_bound);
+
+    *reference_table++ = (uint16)ref_param_count;
+    offset = (uint16)offsetof(WASMFuncObject, params_bound);
+    for (i = 0; i < param_count_bound; i++) {
+        if (wasm_is_type_reftype(func_type_bound->types[i])) {
+            *reference_table++ = (uint16)offset;
+            offset += (uint16)sizeof(WASMValue);
+        }
+    }
     return func_obj;
 }
 
@@ -399,8 +420,12 @@ wasm_object_get_ref_list(WASMObjectRef obj, bool *p_is_compact_mode,
         return true;
     }
     else if (rtt_obj->defined_type->type_flag == WASM_TYPE_FUNC) {
-        /* TODO */
+        /* function object */
-        return false;
+        WASMFuncObjectRef func_obj = (WASMFuncObjectRef)obj;
+        *p_is_compact_mode = false;
+        *p_ref_num = *func_obj->reference_table;
+        *p_ref_list = func_obj->reference_table + 1;
+        return true;
     }
     else if (rtt_obj->defined_type->type_flag == WASM_TYPE_STRUCT) {
         /* struct object */

core/iwasm/common/gc/gc_object.h

@@ -97,6 +97,10 @@ typedef struct WASMFuncObject {
     WASMObjectHeader header;
     uint32 func_idx_bound;
     uint32 param_count_bound;
+    /* Offsets of reference params that need to be traced
+       during GC. The first element of the table is the
+       number of such offsets. */
+    uint16 *reference_table;
     WASMValue params_bound[1];
 } WASMFuncObject, *WASMFuncObjectRef;
 
@@ -225,7 +229,8 @@ wasm_array_obj_elem_addr(const WASMArrayObjectRef array_obj, uint32 elem_idx)
 
 WASMFuncObjectRef
 wasm_func_obj_new(void *heap_handle, WASMRttObjectRef rtt_obj,
-                  uint32 func_idx_bound, uint32 param_count_bound);
+                  const WASMFuncType *func_type_bound, uint32 func_idx_bound,
+                  uint32 param_count_bound);
 
 void
 wasm_func_obj_set_param_bound(WASMFuncObjectRef func_obj, uint32 param_idx,

core/iwasm/interpreter/wasm_interp_classic.c

@@ -1773,7 +1773,11 @@ wasm_interp_call_func_bytecode(WASMModuleInstance *module,
                 func_type_dst =
                     (WASMFuncType *)module->module->types[type_index];
 
-                func_obj_old = POP_REF();
+                SYNC_ALL_TO_FRAME();
+
+                /* Don't POP_REF() here to let the object be tracable
+                   during GC when creating func object below */
+                func_obj_old = GET_REF_FROM_ADDR(frame_sp - REF_CELL_NUM);
                 if (!func_obj_old) {
                     wasm_set_exception(module, "null function object");
                     goto got_exception;
@@ -1794,6 +1798,9 @@ wasm_interp_call_func_bytecode(WASMModuleInstance *module,
                     goto got_exception;
                 }
 
+                /* Pop object after the func object is created */
+                (void)POP_REF();
+
                 param_count_bound =
                     wasm_func_obj_get_param_count_bound(func_obj_old);
                 for (j = 0; j < (int32)param_count_bound; j++) {

core/iwasm/interpreter/wasm_interp_fast.c

@@ -393,14 +393,24 @@ init_frame_refs(uint8 *frame_ref, uint32 cell_num, WASMFunctionInstance *func)
     (opnd_off = GET_OFFSET(), CLEAR_FRAME_REF(opnd_off), \
      GET_REF_FROM_ADDR(frame_lp + opnd_off))
 
+#if WASM_ENABLE_GC != 0
+#define SYNC_FRAME_REF() frame->frame_ref = frame_ref
+#define UPDATE_FRAME_REF() frame_ref = frame->frame_ref
+#else
+#define SYNC_FRAME_REF() (void)0
+#define UPDATE_FRAME_REF() (void)0
+#endif
+
 #define SYNC_ALL_TO_FRAME()   \
     do {                      \
         frame->ip = frame_ip; \
+        SYNC_FRAME_REF();     \
     } while (0)
 
 #define UPDATE_ALL_FROM_FRAME() \
     do {                        \
         frame_ip = frame->ip;   \
+        UPDATE_FRAME_REF();     \
     } while (0)
 
 #if WASM_ENABLE_LABELS_AS_VALUES != 0
@@ -1103,12 +1113,12 @@ wasm_interp_dump_op_count()
     for (i = 0; i < WASM_OP_IMPDEP; i++)
         total_count += opcode_table[i].count;
 
-    printf("total opcode count: %ld\n", total_count);
+    os_printf("total opcode count: %ld\n", total_count);
     for (i = 0; i < WASM_OP_IMPDEP; i++)
         if (opcode_table[i].count > 0)
-            printf("\t\t%s count:\t\t%ld,\t\t%.2f%%\n", opcode_table[i].name,
+            os_printf("\t\t%s count:\t\t%ld,\t\t%.2f%%\n", opcode_table[i].name,
-                   opcode_table[i].count,
+                      opcode_table[i].count,
-                   opcode_table[i].count * 100.0f / total_count);
+                      opcode_table[i].count * 100.0f / total_count);
 }
 #endif
 
@@ -1601,6 +1611,7 @@ wasm_interp_call_func_bytecode(WASMModuleInstance *module,
 #if WASM_ENABLE_GC == 0
                 PUSH_I32(func_idx);
 #else
+                SYNC_ALL_TO_FRAME();
                 if (!(gc_obj = wasm_create_func_obj(module, func_idx, true,
                                                     NULL, true, NULL, 0))) {
                     goto got_exception;
@@ -1654,7 +1665,11 @@ wasm_interp_call_func_bytecode(WASMModuleInstance *module,
                 type_idx = read_uint32(frame_ip);
                 func_type_dst = (WASMFuncType *)module->module->types[type_idx];
 
-                func_obj_old = POP_REF();
+                SYNC_ALL_TO_FRAME();
+
+                opnd_off = GET_OFFSET();
+                func_obj_old = GET_REF_FROM_ADDR(frame_lp + opnd_off);
+
                 if (!func_obj_old) {
                     wasm_set_exception(module, "null function object");
                     goto got_exception;
@@ -1779,6 +1794,8 @@ wasm_interp_call_func_bytecode(WASMModuleInstance *module,
                         struct_type =
                             (WASMStructType *)module->module->types[type_idx];
 
+                        SYNC_ALL_TO_FRAME();
+
                         rtt_obj = POP_REF();
                         struct_obj = wasm_struct_obj_new(module->gc_heap_handle,
                                                          rtt_obj);
@@ -1936,6 +1953,8 @@ wasm_interp_call_func_bytecode(WASMModuleInstance *module,
                             }
                         }
 
+                        SYNC_ALL_TO_FRAME();
+
                         array_obj =
                             wasm_array_obj_new(module->gc_heap_handle, rtt_obj,
                                                array_len, &array_elem);
@@ -3975,6 +3994,8 @@ wasm_interp_call_func_bytecode(WASMModuleInstance *module,
                                 + s,
                             (uint32)(n * sizeof(uint32)));
 #else
+                        SYNC_ALL_TO_FRAME();
+
                         table_elems =
                             (table_elem_type_t *)tbl_inst->base_addr + d;
                         func_indexes = module->module->table_segments[elem_idx]

core/iwasm/interpreter/wasm_runtime.c

@@ -1207,8 +1207,9 @@ wasm_create_func_obj(WASMModuleInstance *module_inst, uint32 func_idx,
         return NULL;
     }
 
-    if (!(func_obj = wasm_func_obj_new(module_inst->gc_heap_handle, rtt_obj,
+    if (!(func_obj =
-                                       func_idx, param_count_bound))) {
+              wasm_func_obj_new(module_inst->gc_heap_handle, rtt_obj, func_type,
+                                func_idx, param_count_bound))) {
         set_error_buf(error_buf, error_buf_size, "create func object failed");
         return NULL;
     }