FIXES bytecodealliance#137: make calling wasm from python 7x faster

wasmtime/_func.py

@@ -7,7 +7,8 @@
 from typing import Callable, Optional, Generic, TypeVar, List, Union, Tuple, cast as cast_type, Sequence
 from ._exportable import AsExtern
 from ._store import Storelike
-from ._bindings import wasmtime_val_raw_t, wasm_valtype_kind
+from ._bindings import wasmtime_val_raw_t, wasm_valtype_kind, wasmtime_val_t, wasmtime_externref_t, wasmtime_func_t
+from ._value import _unintern
 from ._ffi import (
     WASMTIME_I32,
     WASMTIME_I64,
@@ -18,6 +19,7 @@
     WASMTIME_EXTERNREF,
     WASM_ANYREF,
     WASM_FUNCREF,
+    wasmtime_externref_data,
 )
 
 
@@ -40,11 +42,41 @@
 def get_valtype_attr(ty: ValType):
     return val_id2attr[wasm_valtype_kind(ty._ptr)]
 
+from struct import Struct
+
+def val_getter(store_id, val_raw, attr):
+    val = getattr(val_raw, attr)
+
+    if attr=='externref':
+        ptr = ctypes.POINTER(wasmtime_externref_t)
+        if not val: return None
+        ffi = ptr.from_address(val)
+        if not ffi: return
+        extern_id = wasmtime_externref_data(ffi)
+        ret = _unintern(extern_id)
+        return ret
+    elif attr=='funcref':
+        if val==0: return None
+        f=wasmtime_func_t()
+        f.store_id=store_id
+        f.index=val
+        ret=Func._from_raw(f)
+        return ret
+    return val
+
 def val_setter(dst, attr, val):
     if attr=='externref':
-        # TODO: handle None
-        v = Val.externref(val)
-        casted = ctypes.addressof(v._raw.of.externref)
+        if isinstance(val, Val) and val._raw.kind==WASMTIME_EXTERNREF.value:
+            if val._raw.of.externref:
+                extern_id = wasmtime_externref_data(val._raw.of.externref)
+            casted = ctypes.addressof(val._raw.of.externref)
+        else:
+            v = Val.externref(val)
+            casted = ctypes.addressof(v._raw.of.externref)
+    elif attr=='funcref':
+        if isinstance(val, Val) and val._raw.kind==WASMTIME_FUNCREF.value:
+            casted = val._raw.of.funcref.index
+        else: raise RuntimeError("foo")
     elif isinstance(val, Func):
         # TODO: handle null_funcref
         # TODO: validate same val._func.store_id
@@ -112,9 +144,10 @@ def _extract_return(self, vals_raw: ctypes.Array[wasmtime_val_raw_t]) -> Union[I
         if self._results_n==0:
             return None
         if self._results_n==1:
-            return getattr(vals_raw[0], self._results_str0)
+            ret = val_getter(self._func.store_id, vals_raw[0], self._results_str0)
+            return ret
         # we can use tuple construct, but I'm using list for compatability
-        return [getattr(val_raw, ret_str) for val_raw, ret_str in zip(vals_raw, self._results_str)]
+        return [val_getter(self._func.store_id, val_raw, ret_str) for val_raw, ret_str in zip(vals_raw, self._results_str)]
 
     def _init_call(self, ty: FuncType):
         """init signature properties used by call"""
@@ -123,8 +156,8 @@ def _init_call(self, ty: FuncType):
         ty_results = ty.results
         params_n = len(ty_params)
         results_n = len(ty_results)
-        self._params_str = (get_valtype_attr(i) for i in ty_params)
-        self._results_str = (get_valtype_attr(i) for i in ty_results)
+        self._params_str = [get_valtype_attr(i) for i in ty_params]
+        self._results_str = [get_valtype_attr(i) for i in ty_results]
         self._results_str0 = get_valtype_attr(ty_results[0]) if results_n else None
         self._params_n = params_n
         self._results_n = results_n