[wasm] Move fast path of wasm RefFunc to a builtin

- Use a builtin for the fast path of Wasm RefFunc.
- Simplify the runtime function by passing instance as first
  argument.

Change-Id: I5f6993cae21a878cee21a391a25c4d574243058b
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2144533
Commit-Queue: Bill Budge <bbudge@chromium.org>
Reviewed-by: Andreas Haas <ahaas@chromium.org>
Cr-Commit-Position: refs/heads/master@{#67346}

src/builtins/builtins-definitions.h

@@ -850,6 +850,7 @@ namespace internal {
   TFC(WasmI64AtomicWait32, WasmI64AtomicWait32)                                \
   TFC(WasmI64AtomicWait64, WasmI64AtomicWait64)                                \
   TFC(WasmMemoryGrow, WasmMemoryGrow)                                          \
+  TFC(WasmRefFunc, WasmRefFunc)                                                \
   TFC(WasmTableInit, WasmTableInit)                                            \
   TFC(WasmTableCopy, WasmTableCopy)                                            \
   TFC(WasmTableGet, WasmTableGet)                                              \

src/builtins/builtins-wasm-gen.cc

@@ -256,6 +256,32 @@ TF_BUILTIN(WasmMemoryGrow, WasmBuiltinsAssembler) {
   Return(Int32Constant(-1));
 }
 
+TF_BUILTIN(WasmRefFunc, WasmBuiltinsAssembler) {
+  TNode<WasmInstanceObject> instance = LoadInstanceFromFrame();
+
+  Label call_runtime(this, Label::kDeferred);
+
+  TNode<Uint32T> raw_index =
+      UncheckedCast<Uint32T>(Parameter(Descriptor::kFunctionIndex));
+  TNode<FixedArray> table = LoadObjectField<FixedArray>(
+      instance, WasmInstanceObject::kWasmExternalFunctionsOffset);
+  GotoIf(IsUndefined(table), &call_runtime);
+
+  TNode<IntPtrT> function_index =
+      UncheckedCast<IntPtrT>(ChangeUint32ToWord(raw_index));
+  // Function index should be in range.
+  TNode<Object> result = LoadFixedArrayElement(table, function_index);
+  GotoIf(IsUndefined(result), &call_runtime);
+
+  Return(result);
+
+  BIND(&call_runtime);
+  // Fall back to the runtime call for more complex cases.
+  // function_index is known to be in Smi range.
+  TailCallRuntime(Runtime::kWasmRefFunc, LoadContextFromInstance(instance),
+                  instance, SmiFromUint32(raw_index));
+}
+
 TF_BUILTIN(WasmTableInit, WasmBuiltinsAssembler) {
   TNode<Uint32T> dst_raw =
       UncheckedCast<Uint32T>(Parameter(Descriptor::kDestination));

src/codegen/interface-descriptors.cc

@@ -411,6 +411,11 @@ void WasmMemoryGrowDescriptor::InitializePlatformSpecific(
   DefaultInitializePlatformSpecific(data, kParameterCount);
 }
 
+void WasmRefFuncDescriptor::InitializePlatformSpecific(
+    CallInterfaceDescriptorData* data) {
+  DefaultInitializePlatformSpecific(data, kParameterCount);
+}
+
 void WasmTableInitDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   DefaultInitializePlatformSpecific(data,

src/codegen/interface-descriptors.h

@@ -101,6 +101,7 @@ namespace internal {
   V(WasmI64AtomicWait32)              \
   V(WasmI64AtomicWait64)              \
   V(WasmMemoryGrow)                   \
+  V(WasmRefFunc)                      \
   V(WasmTableInit)                    \
   V(WasmTableCopy)                    \
   V(WasmTableGet)                     \
@@ -1363,6 +1364,14 @@ class WasmMemoryGrowDescriptor final : public CallInterfaceDescriptor {
   DECLARE_DESCRIPTOR(WasmMemoryGrowDescriptor, CallInterfaceDescriptor)
 };
 
+class WasmRefFuncDescriptor final : public CallInterfaceDescriptor {
+ public:
+  DEFINE_PARAMETERS_NO_CONTEXT(kFunctionIndex)
+  DEFINE_RESULT_AND_PARAMETER_TYPES(MachineType::AnyTagged(),  // result
+                                    MachineType::Uint32())     // kFunctionIndex
+  DECLARE_DESCRIPTOR(WasmRefFuncDescriptor, CallInterfaceDescriptor)
+};
+
 class WasmTableInitDescriptor final : public CallInterfaceDescriptor {
  public:
   DEFINE_PARAMETERS_NO_CONTEXT(kDestination, kSource, kSize, kTableIndex,

src/compiler/wasm-compiler.cc

@@ -144,6 +144,19 @@ bool ContainsInt64(const wasm::FunctionSig* sig) {
   }
   return false;
 }
+
+template <typename BuiltinDescriptor>
+CallDescriptor* GetBuiltinCallDescriptor(WasmGraphBuilder* builder,
+                                         StubCallMode stub_mode) {
+  BuiltinDescriptor interface_descriptor;
+  return Linkage::GetStubCallDescriptor(
+      builder->mcgraph()->zone(),                     // zone
+      interface_descriptor,                           // descriptor
+      interface_descriptor.GetStackParameterCount(),  // stack parameter count
+      CallDescriptor::kNoFlags,                       // flags
+      Operator::kNoProperties,                        // properties
+      stub_mode);                                     // stub call mode
+}
 }  // namespace
 
 class WasmGraphAssembler : public GraphAssembler {
@@ -262,11 +275,16 @@ Node* WasmGraphBuilder::RefNull() {
 }
 
 Node* WasmGraphBuilder::RefFunc(uint32_t function_index) {
-  Node* args[] = {
-      graph()->NewNode(mcgraph()->common()->NumberConstant(function_index))};
-  Node* result =
-      BuildCallToRuntime(Runtime::kWasmRefFunc, args, arraysize(args));
-  return result;
+  auto call_descriptor = GetBuiltinCallDescriptor<WasmRefFuncDescriptor>(
+      this, StubCallMode::kCallWasmRuntimeStub);
+  // A direct call to a wasm runtime stub defined in this module.
+  // Just encode the stub index. This will be patched at relocation.
+  Node* call_target = mcgraph()->RelocatableIntPtrConstant(
+      wasm::WasmCode::kWasmRefFunc, RelocInfo::WASM_STUB_CALL);
+
+  return SetEffectControl(
+      graph()->NewNode(mcgraph()->common()->Call(call_descriptor), call_target,
+                       Uint32Constant(function_index), effect(), control()));
 }
 
 Node* WasmGraphBuilder::NoContextConstant() {
@@ -1938,19 +1956,6 @@ ExternalReference convert_ccall_ref(WasmGraphBuilder* builder,
   }
 }
 
-template <typename BuiltinDescriptor>
-CallDescriptor* GetBuiltinCallDescriptor(WasmGraphBuilder* builder,
-                                         StubCallMode stub_mode) {
-  BuiltinDescriptor interface_descriptor;
-  return Linkage::GetStubCallDescriptor(
-      builder->mcgraph()->zone(),                     // zone
-      interface_descriptor,                           // descriptor
-      interface_descriptor.GetStackParameterCount(),  // stack parameter count
-      CallDescriptor::kNoFlags,                       // flags
-      Operator::kNoProperties,                        // properties
-      stub_mode);                                     // stub call mode
-}
-
 }  // namespace
 
 Node* WasmGraphBuilder::BuildCcallConvertFloat(Node* input,

src/runtime/runtime-wasm.cc

@@ -447,12 +447,9 @@ Object ThrowTableOutOfBounds(Isolate* isolate,
 RUNTIME_FUNCTION(Runtime_WasmRefFunc) {
   ClearThreadInWasmScope flag_scope;
   HandleScope scope(isolate);
-  DCHECK_EQ(1, args.length());
-  auto instance =
-      Handle<WasmInstanceObject>(GetWasmInstanceOnStackTop(isolate), isolate);
-  DCHECK(isolate->context().is_null());
-  isolate->set_context(instance->native_context());
-  CONVERT_UINT32_ARG_CHECKED(function_index, 0);
+  DCHECK_EQ(2, args.length());
+  CONVERT_ARG_HANDLE_CHECKED(WasmInstanceObject, instance, 0);
+  CONVERT_UINT32_ARG_CHECKED(function_index, 1);
 
   Handle<WasmExternalFunction> function =
       WasmInstanceObject::GetOrCreateWasmExternalFunction(isolate, instance,

src/wasm/wasm-code-manager.h

@@ -60,6 +60,7 @@ struct WasmModule;
   V(WasmI32AtomicWait64)                 \
   V(WasmI64AtomicWait32)                 \
   V(WasmI64AtomicWait64)                 \
+  V(WasmRefFunc)                         \
   V(WasmMemoryGrow)                      \
   V(WasmTableInit)                       \
   V(WasmTableCopy)                       \