[wasm] Refactor Table.Set

The old implementation of Table.Set in wasm-js.cc accessed information
which should be hidden from this level of abstraction, e.g. the internal
structure of a WasmTableObject. With this CL, all that is done in
wasm-js.cc is the extraction of parameters. The actual logic is happening
in wasm-module.{h|cc}. This CL will also make refactoring wasm-module.cc
easier.

R=clemensh@chromium.org, mtrofin@chromium.org

Change-Id: Ifbce6f739459dffc9f9d47e4cd8227638867f3e9
Reviewed-on: https://chromium-review.googlesource.com/525694
Commit-Queue: Andreas Haas <ahaas@chromium.org>
Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#45754}

src/wasm/wasm-js.cc

@@ -702,6 +702,16 @@ void WebAssemblyTableSet(const v8::FunctionCallbackInfo<v8::Value>& args) {
     thrower.TypeError("Argument 1 must be null or a function");
     return;
   }
+
+  // {This} parameter.
+  auto receiver =
+      i::Handle<i::WasmTableObject>::cast(Utils::OpenHandle(*args.This()));
+
+  // Parameter 0.
+  int32_t index;
+  if (!args[0]->Int32Value(context).To(&index)) return;
+
+  // Parameter 1.
   i::Handle<i::Object> value = Utils::OpenHandle(*args[1]);
   if (!value->IsNull(i_isolate) &&
       (!value->IsJSFunction() ||
@@ -711,27 +721,10 @@ void WebAssemblyTableSet(const v8::FunctionCallbackInfo<v8::Value>& args) {
     return;
   }
 
-  auto receiver =
-      i::Handle<i::WasmTableObject>::cast(Utils::OpenHandle(*args.This()));
-  i::Handle<i::FixedArray> array(receiver->functions(), i_isolate);
-  int i;
-  if (!args[0]->Int32Value(context).To(&i)) return;
-  if (i < 0 || i >= array->length()) {
-    thrower.RangeError("index out of bounds");
-    return;
-  }
-
-  i::Handle<i::FixedArray> dispatch_tables(receiver->dispatch_tables(),
-                                           i_isolate);
-  if (value->IsNull(i_isolate)) {
-    i::wasm::UpdateDispatchTables(i_isolate, dispatch_tables, i,
-                                  i::Handle<i::JSFunction>::null());
-  } else {
-    i::wasm::UpdateDispatchTables(i_isolate, dispatch_tables, i,
-                                  i::Handle<i::JSFunction>::cast(value));
-  }
-
-  i::Handle<i::FixedArray>::cast(array)->set(i, *value);
+  i::wasm::TableSet(&thrower, i_isolate, receiver, index,
+                    value->IsNull(i_isolate)
+                        ? i::Handle<i::JSFunction>::null()
+                        : i::Handle<i::JSFunction>::cast(value));
 }
 
 // WebAssembly.Memory.grow(num) -> num

src/wasm/wasm-module.cc

@@ -1095,9 +1095,9 @@ Handle<Code> CompileImportWrapper(Isolate* isolate, int index, FunctionSig* sig,
                                           module_name, import_name, origin);
 }
 
-void UpdateDispatchTablesInternal(Isolate* isolate,
-                                  Handle<FixedArray> dispatch_tables, int index,
-                                  WasmFunction* function, Handle<Code> code) {
+void UpdateDispatchTables(Isolate* isolate, Handle<FixedArray> dispatch_tables,
+                          int index, WasmFunction* function,
+                          Handle<Code> code) {
   DCHECK_EQ(0, dispatch_tables->length() % 4);
   for (int i = 0; i < dispatch_tables->length(); i += 4) {
     int table_index = Smi::cast(dispatch_tables->get(i + 1))->value();
@@ -1123,18 +1123,30 @@ void UpdateDispatchTablesInternal(Isolate* isolate,
 
 }  // namespace
 
-void wasm::UpdateDispatchTables(Isolate* isolate,
-                                Handle<FixedArray> dispatch_tables, int index,
-                                Handle<JSFunction> function) {
-  if (function.is_null()) {
-    UpdateDispatchTablesInternal(isolate, dispatch_tables, index, nullptr,
-                                 Handle<Code>::null());
-  } else {
-    UpdateDispatchTablesInternal(
-        isolate, dispatch_tables, index,
-        GetWasmFunctionForImportWrapper(isolate, function),
-        UnwrapImportWrapper(function));
+void wasm::TableSet(ErrorThrower* thrower, Isolate* isolate,
+                    Handle<WasmTableObject> table, int32_t index,
+                    Handle<JSFunction> function) {
+  Handle<FixedArray> array(table->functions(), isolate);
+
+  if (index < 0 || index >= array->length()) {
+    thrower->RangeError("index out of bounds");
+    return;
+  }
+
+  Handle<FixedArray> dispatch_tables(table->dispatch_tables(), isolate);
+
+  WasmFunction* wasm_function = nullptr;
+  Handle<Code> code = Handle<Code>::null();
+  Handle<Object> value = handle(isolate->heap()->null_value());
+
+  if (!function.is_null()) {
+    wasm_function = GetWasmFunctionForImportWrapper(isolate, function);
+    code = UnwrapImportWrapper(function);
+    value = Handle<Object>::cast(function);
   }
+
+  UpdateDispatchTables(isolate, dispatch_tables, index, wasm_function, code);
+  array->set(index, *value);
 }
 
 // A helper class to simplify instantiating a module from a compiled module.
@@ -2305,8 +2317,8 @@ class InstantiationHelper {
             table_instance.js_wrappers->set(table_index,
                                             *js_wrappers_[func_index]);
 
-            UpdateDispatchTablesInternal(isolate_, all_dispatch_tables,
-                                         table_index, function, wasm_code);
+            UpdateDispatchTables(isolate_, all_dispatch_tables, table_index,
+                                 function, wasm_code);
           }
         }
       }

src/wasm/wasm-module.h

@@ -15,6 +15,7 @@
 #include "src/parsing/preparse-data.h"
 
 #include "src/wasm/signature-map.h"
+#include "src/wasm/wasm-objects.h"
 #include "src/wasm/wasm-opcodes.h"
 
 namespace v8 {
@@ -440,8 +441,9 @@ void DetachWebAssemblyMemoryBuffer(Isolate* isolate,
                                    Handle<JSArrayBuffer> buffer,
                                    bool free_memory);
 
-void UpdateDispatchTables(Isolate* isolate, Handle<FixedArray> dispatch_tables,
-                          int index, Handle<JSFunction> js_function);
+void TableSet(ErrorThrower* thrower, Isolate* isolate,
+              Handle<WasmTableObject> table, int32_t index,
+              Handle<JSFunction> function);
 
 //============================================================================
 //== Compilation and instantiation ===========================================