Remove distinction between lazy and non-lazy CallApiCallback, always...

Remove distinction between lazy and non-lazy CallApiCallback, always explicitly set up target context

Bug: 
Change-Id: I0cb751a0415433fdfec21451e2fac3e0726bf26e
Reviewed-on: https://chromium-review.googlesource.com/743019
Commit-Queue: Toon Verwaest <verwaest@chromium.org>
Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49024}

src/arm/code-stubs-arm.cc

@@ -1467,7 +1467,6 @@ static void CallApiFunctionAndReturn(MacroAssembler* masm,
 
 void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- r0                  : callee
   //  -- r4                  : call_data
   //  -- r2                  : holder
   //  -- r1                  : api_function_address
@@ -1479,11 +1478,9 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   //  -- sp[argc * 4]        : receiver
   // -----------------------------------
 
-  Register callee = r0;
   Register call_data = r4;
   Register holder = r2;
   Register api_function_address = r1;
-  Register context = cp;
 
   typedef FunctionCallbackArguments FCA;
 
@@ -1515,12 +1512,6 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // holder
   __ push(holder);
 
-  // enter a new context
-  if (!is_lazy()) {
-    // load context from callee
-    __ ldr(context, FieldMemOperand(callee, JSFunction::kContextOffset));
-  }
-
   // Prepare arguments.
   __ mov(scratch0, sp);
 

src/arm/interface-descriptors-arm.cc

@@ -284,10 +284,10 @@ void ApiCallbackDescriptor::InitializePlatformSpecific(
       PlatformInterfaceDescriptor(CAN_INLINE_TARGET_ADDRESS);
 
   Register registers[] = {
-      r0,  // callee
-      r4,  // call_data
-      r2,  // holder
-      r1,  // api_function_address
+      JavaScriptFrame::context_register(),  // callee context
+      r4,                                   // call_data
+      r2,                                   // holder
+      r1,                                   // api_function_address
   };
   data->InitializePlatformSpecific(arraysize(registers), registers,
                                    &default_descriptor);

src/arm64/code-stubs-arm64.cc

@@ -1690,7 +1690,6 @@ static void CallApiFunctionAndReturn(MacroAssembler* masm,
 
 void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- x0                  : callee
   //  -- x4                  : call_data
   //  -- x2                  : holder
   //  -- x1                  : api_function_address
@@ -1702,11 +1701,9 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   //  -- sp[argc * 8]        : receiver
   // -----------------------------------
 
-  Register callee = x0;
   Register call_data = x4;
   Register holder = x2;
   Register api_function_address = x1;
-  Register context = cp;
 
   typedef FunctionCallbackArguments FCA;
 
@@ -1731,12 +1728,6 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   //    return value, return value default, isolate, holder.
   __ Push(undef, undef, isolate_reg, holder);
 
-  // Enter a new context.
-  if (!is_lazy()) {
-    // Load context from callee.
-    __ Ldr(context, FieldMemOperand(callee, JSFunction::kContextOffset));
-  }
-
   // Prepare arguments.
   Register args = x6;
   __ Mov(args, masm->StackPointer());

src/arm64/interface-descriptors-arm64.cc

@@ -295,10 +295,10 @@ void ApiCallbackDescriptor::InitializePlatformSpecific(
       PlatformInterfaceDescriptor(CAN_INLINE_TARGET_ADDRESS);
 
   Register registers[] = {
-      x0,  // callee
-      x4,  // call_data
-      x2,  // holder
-      x1,  // api_function_address
+      JavaScriptFrame::context_register(),  // callee context
+      x4,                                   // call_data
+      x2,                                   // holder
+      x1,                                   // api_function_address
   };
   data->InitializePlatformSpecific(arraysize(registers), registers,
                                    &default_descriptor);

src/code-stubs.h

@@ -632,29 +632,25 @@ class CallApiCallbackStub : public PlatformCodeStub {
   static const int kArgMax = (1 << kArgBits) - 1;
 
   // CallApiCallbackStub for regular setters and getters.
-  CallApiCallbackStub(Isolate* isolate, bool is_store, bool is_lazy)
-      : CallApiCallbackStub(isolate, is_store ? 1 : 0, is_store, is_lazy) {}
+  CallApiCallbackStub(Isolate* isolate, bool is_store)
+      : CallApiCallbackStub(isolate, is_store ? 1 : 0, is_store) {}
 
   // CallApiCallbackStub for callback functions.
-  CallApiCallbackStub(Isolate* isolate, int argc, bool is_lazy)
-      : CallApiCallbackStub(isolate, argc, false, is_lazy) {}
+  CallApiCallbackStub(Isolate* isolate, int argc)
+      : CallApiCallbackStub(isolate, argc, false) {}
 
  private:
-  CallApiCallbackStub(Isolate* isolate, int argc, bool is_store, bool is_lazy)
+  CallApiCallbackStub(Isolate* isolate, int argc, bool is_store)
       : PlatformCodeStub(isolate) {
     CHECK(0 <= argc && argc <= kArgMax);
-    minor_key_ = IsStoreBits::encode(is_store) |
-                 ArgumentBits::encode(argc) |
-                 IsLazyAccessorBits::encode(is_lazy);
+    minor_key_ = IsStoreBits::encode(is_store) | ArgumentBits::encode(argc);
   }
 
   bool is_store() const { return IsStoreBits::decode(minor_key_); }
-  bool is_lazy() const { return IsLazyAccessorBits::decode(minor_key_); }
   int argc() const { return ArgumentBits::decode(minor_key_); }
 
   class IsStoreBits: public BitField<bool, 0, 1> {};
-  class IsLazyAccessorBits : public BitField<bool, 1, 1> {};
-  class ArgumentBits : public BitField<int, 2, kArgBits> {};
+  class ArgumentBits : public BitField<int, 1, kArgBits> {};
 
   DEFINE_CALL_INTERFACE_DESCRIPTOR(ApiCallback);
   DEFINE_PLATFORM_CODE_STUB(CallApiCallback, PlatformCodeStub);

src/compiler/js-call-reducer.cc

@@ -1562,8 +1562,8 @@ Node* JSCallReducer::SafeLoadElement(ElementsKind kind, Node* receiver,
   return element;
 }
 
-Reduction JSCallReducer::ReduceCallApiFunction(
-    Node* node, Handle<FunctionTemplateInfo> function_template_info) {
+Reduction JSCallReducer::ReduceCallApiFunction(Node* node,
+                                               Handle<JSFunction> function) {
   DCHECK_EQ(IrOpcode::kJSCall, node->opcode());
   CallParameters const& p = CallParametersOf(node->op());
   int const argc = static_cast<int>(p.arity()) - 2;
@@ -1572,6 +1572,10 @@ Reduction JSCallReducer::ReduceCallApiFunction(
                        : NodeProperties::GetValueInput(node, 1);
   Node* effect = NodeProperties::GetEffectInput(node);
 
+  Handle<FunctionTemplateInfo> function_template_info(
+      FunctionTemplateInfo::cast(function->shared()->function_data()));
+  Handle<Context> context(function->context());
+
   // CallApiCallbackStub expects the target in a register, so we count it out,
   // and counts the receiver as an implicit argument, so we count the receiver
   // out too.
@@ -1627,13 +1631,13 @@ Reduction JSCallReducer::ReduceCallApiFunction(
   Handle<CallHandlerInfo> call_handler_info(
       CallHandlerInfo::cast(function_template_info->call_code()), isolate());
   Handle<Object> data(call_handler_info->data(), isolate());
-  CallApiCallbackStub stub(isolate(), argc, false);
+  CallApiCallbackStub stub(isolate(), argc);
   CallInterfaceDescriptor cid = stub.GetCallInterfaceDescriptor();
   CallDescriptor* call_descriptor = Linkage::GetStubCallDescriptor(
       isolate(), graph()->zone(), cid,
       cid.GetStackParameterCount() + argc + 1 /* implicit receiver */,
       CallDescriptor::kNeedsFrameState, Operator::kNoProperties,
-      MachineType::AnyTagged(), 1);
+      MachineType::AnyTagged(), 1, Linkage::kNoContext);
   ApiFunction api_function(v8::ToCData<Address>(call_handler_info->callback()));
   Node* holder = lookup == CallOptimization::kHolderFound
                      ? jsgraph()->HeapConstant(api_holder)
@@ -1642,11 +1646,14 @@ Reduction JSCallReducer::ReduceCallApiFunction(
       &api_function, ExternalReference::DIRECT_API_CALL, isolate());
   node->InsertInput(graph()->zone(), 0,
                     jsgraph()->HeapConstant(stub.GetCode()));
+  node->ReplaceInput(1, jsgraph()->Constant(context));
   node->InsertInput(graph()->zone(), 2, jsgraph()->Constant(data));
   node->InsertInput(graph()->zone(), 3, holder);
   node->InsertInput(graph()->zone(), 4,
                     jsgraph()->ExternalConstant(function_reference));
   node->ReplaceInput(5, receiver);
+  // Remove context input.
+  node->RemoveInput(6 + argc);
   NodeProperties::ChangeOp(node, common()->Call(call_descriptor));
   return Changed(node);
 }
@@ -1989,9 +1996,7 @@ Reduction JSCallReducer::ReduceJSCall(Node* node) {
       }
 
       if (!FLAG_runtime_stats && shared->IsApiFunction()) {
-        Handle<FunctionTemplateInfo> function_template_info(
-            FunctionTemplateInfo::cast(shared->function_data()), isolate());
-        return ReduceCallApiFunction(node, function_template_info);
+        return ReduceCallApiFunction(node, function);
       }
     } else if (m.Value()->IsJSBoundFunction()) {
       Handle<JSBoundFunction> function =

src/compiler/js-call-reducer.h

@@ -54,8 +54,7 @@ class JSCallReducer final : public AdvancedReducer {
  private:
   Reduction ReduceArrayConstructor(Node* node);
   Reduction ReduceBooleanConstructor(Node* node);
-  Reduction ReduceCallApiFunction(
-      Node* node, Handle<FunctionTemplateInfo> function_template_info);
+  Reduction ReduceCallApiFunction(Node* node, Handle<JSFunction> function);
   Reduction ReduceNumberConstructor(Node* node);
   Reduction ReduceFunctionPrototypeApply(Node* node);
   Reduction ReduceFunctionPrototypeBind(Node* node);

src/compiler/js-native-context-specialization.cc

@@ -1612,9 +1612,8 @@ Node* JSNativeContextSpecialization::InlinePropertyGetterCall(
         access_info.holder().is_null()
             ? receiver
             : jsgraph()->Constant(access_info.holder().ToHandleChecked());
-    value =
-        InlineApiCall(receiver, holder, context, target, frame_state0, nullptr,
-                      effect, control, shared_info, function_template_info);
+    value = InlineApiCall(receiver, holder, frame_state0, nullptr, effect,
+                          control, shared_info, function_template_info);
   }
   // Remember to rewire the IfException edge if this is inside a try-block.
   if (if_exceptions != nullptr) {
@@ -1664,9 +1663,8 @@ Node* JSNativeContextSpecialization::InlinePropertySetterCall(
         access_info.holder().is_null()
             ? receiver
             : jsgraph()->Constant(access_info.holder().ToHandleChecked());
-    value =
-        InlineApiCall(receiver, holder, context, target, frame_state0, value,
-                      effect, control, shared_info, function_template_info);
+    value = InlineApiCall(receiver, holder, frame_state0, value, effect,
+                          control, shared_info, function_template_info);
   }
   // Remember to rewire the IfException edge if this is inside a try-block.
   if (if_exceptions != nullptr) {
@@ -1681,9 +1679,8 @@ Node* JSNativeContextSpecialization::InlinePropertySetterCall(
 }
 
 Node* JSNativeContextSpecialization::InlineApiCall(
-    Node* receiver, Node* holder, Node* context, Node* target,
-    Node* frame_state, Node* value, Node** effect, Node** control,
-    Handle<SharedFunctionInfo> shared_info,
+    Node* receiver, Node* holder, Node* frame_state, Node* value, Node** effect,
+    Node** control, Handle<SharedFunctionInfo> shared_info,
     Handle<FunctionTemplateInfo> function_template_info) {
   Handle<CallHandlerInfo> call_handler_info = handle(
       CallHandlerInfo::cast(function_template_info->call_code()), isolate());
@@ -1692,9 +1689,7 @@ Node* JSNativeContextSpecialization::InlineApiCall(
   // Only setters have a value.
   int const argc = value == nullptr ? 0 : 1;
   // The stub always expects the receiver as the first param on the stack.
-  CallApiCallbackStub stub(
-      isolate(), argc,
-      true /* FunctionTemplateInfo doesn't have an associated context. */);
+  CallApiCallbackStub stub(isolate(), argc);
   CallInterfaceDescriptor call_interface_descriptor =
       stub.GetCallInterfaceDescriptor();
   CallDescriptor* call_descriptor = Linkage::GetStubCallDescriptor(
@@ -1702,7 +1697,7 @@ Node* JSNativeContextSpecialization::InlineApiCall(
       call_interface_descriptor.GetStackParameterCount() + argc +
           1 /* implicit receiver */,
       CallDescriptor::kNeedsFrameState, Operator::kNoProperties,
-      MachineType::AnyTagged(), 1);
+      MachineType::AnyTagged(), 1, Linkage::kNoContext);
 
   Node* data = jsgraph()->Constant(call_data_object);
   ApiFunction function(v8::ToCData<Address>(call_handler_info->callback()));
@@ -1712,9 +1707,10 @@ Node* JSNativeContextSpecialization::InlineApiCall(
   Node* code = jsgraph()->HeapConstant(stub.GetCode());
 
   // Add CallApiCallbackStub's register argument as well.
-  Node* inputs[11] = {code, target, data, holder, function_reference, receiver};
+  Node* context = jsgraph()->Constant(native_context());
+  Node* inputs[10] = {code,    context, data, holder, function_reference,
+                      receiver};
   int index = 6 + argc;
-  inputs[index++] = context;
   inputs[index++] = frame_state;
   inputs[index++] = *effect;
   inputs[index++] = *control;

src/compiler/js-native-context-specialization.h

@@ -145,9 +145,9 @@ class JSNativeContextSpecialization final : public AdvancedReducer {
                                  Node** control,
                                  ZoneVector<Node*>* if_exceptions,
                                  PropertyAccessInfo const& access_info);
-  Node* InlineApiCall(Node* receiver, Node* holder, Node* context, Node* target,
-                      Node* frame_state, Node* value, Node** effect,
-                      Node** control, Handle<SharedFunctionInfo> shared_info,
+  Node* InlineApiCall(Node* receiver, Node* holder, Node* frame_state,
+                      Node* value, Node** effect, Node** control,
+                      Handle<SharedFunctionInfo> shared_info,
                       Handle<FunctionTemplateInfo> function_template_info);
 
   // Construct the appropriate subgraph for element access.

src/ia32/code-stubs-ia32.cc

@@ -1420,7 +1420,6 @@ static void CallApiFunctionAndReturn(MacroAssembler* masm,
 
 void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- edi                 : callee
   //  -- ebx                 : call_data
   //  -- ecx                 : holder
   //  -- edx                 : api_function_address
@@ -1433,11 +1432,9 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   //  -- esp[(argc + 1) * 4] : receiver
   // -----------------------------------
 
-  Register callee = edi;
   Register call_data = ebx;
   Register holder = ecx;
   Register api_function_address = edx;
-  Register context = esi;
   Register return_address = eax;
 
   typedef FunctionCallbackArguments FCA;
@@ -1467,12 +1464,7 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // holder
   __ push(holder);
 
-  // enter a new context
   Register scratch = call_data;
-  if (!is_lazy()) {
-    // load context from callee
-    __ mov(context, FieldOperand(callee, JSFunction::kContextOffset));
-  }
 
   __ mov(scratch, esp);
 

src/ia32/interface-descriptors-ia32.cc

@@ -281,10 +281,10 @@ void ArgumentAdaptorDescriptor::InitializePlatformSpecific(
 void ApiCallbackDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
-      edi,  // callee
-      ebx,  // call_data
-      ecx,  // holder
-      edx,  // api_function_address
+      JavaScriptFrame::context_register(),  // callee context
+      ebx,                                  // call_data
+      ecx,                                  // holder
+      edx,                                  // api_function_address
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/ic/arm/handler-compiler-arm.cc

@@ -241,7 +241,7 @@ void PropertyHandlerCompiler::GenerateApiAccessorCall(
   __ mov(api_function_address, Operand(ref));
 
   // Jump to stub.
-  CallApiCallbackStub stub(isolate, is_store, !optimization.is_constant_call());
+  CallApiCallbackStub stub(isolate, is_store);
   __ TailCallStub(&stub);
 }
 

src/ic/arm64/handler-compiler-arm64.cc

@@ -175,7 +175,7 @@ void PropertyHandlerCompiler::GenerateApiAccessorCall(
   __ Mov(api_function_address, ref);
 
   // Jump to stub.
-  CallApiCallbackStub stub(isolate, is_store, !optimization.is_constant_call());
+  CallApiCallbackStub stub(isolate, is_store);
   __ TailCallStub(&stub);
 }
 

src/ic/ia32/handler-compiler-ia32.cc

@@ -174,7 +174,7 @@ void PropertyHandlerCompiler::GenerateApiAccessorCall(
   __ mov(api_function_address, Immediate(function_address));
 
   // Jump to stub.
-  CallApiCallbackStub stub(isolate, is_store, !optimization.is_constant_call());
+  CallApiCallbackStub stub(isolate, is_store);
   __ TailCallStub(&stub);
 }
 

src/ic/mips/handler-compiler-mips.cc

@@ -231,7 +231,7 @@ void PropertyHandlerCompiler::GenerateApiAccessorCall(
   __ li(api_function_address, Operand(ref));
 
   // Jump to stub.
-  CallApiCallbackStub stub(isolate, is_store, !optimization.is_constant_call());
+  CallApiCallbackStub stub(isolate, is_store);
   __ TailCallStub(&stub);
 }
 

src/ic/mips64/handler-compiler-mips64.cc

@@ -231,7 +231,7 @@ void PropertyHandlerCompiler::GenerateApiAccessorCall(
   __ li(api_function_address, Operand(ref));
 
   // Jump to stub.
-  CallApiCallbackStub stub(isolate, is_store, !optimization.is_constant_call());
+  CallApiCallbackStub stub(isolate, is_store);
   __ TailCallStub(&stub);
 }
 

src/ic/ppc/handler-compiler-ppc.cc

@@ -237,7 +237,7 @@ void PropertyHandlerCompiler::GenerateApiAccessorCall(
   __ mov(api_function_address, Operand(ref));
 
   // Jump to stub.
-  CallApiCallbackStub stub(isolate, is_store, !optimization.is_constant_call());
+  CallApiCallbackStub stub(isolate, is_store);
   __ TailCallStub(&stub);
 }
 

src/ic/s390/handler-compiler-s390.cc

@@ -230,7 +230,7 @@ void PropertyHandlerCompiler::GenerateApiAccessorCall(
   __ mov(api_function_address, Operand(ref));
 
   // Jump to stub.
-  CallApiCallbackStub stub(isolate, is_store, !optimization.is_constant_call());
+  CallApiCallbackStub stub(isolate, is_store);
   __ TailCallStub(&stub);
 }
 

src/ic/x64/handler-compiler-x64.cc

@@ -157,7 +157,7 @@ void PropertyHandlerCompiler::GenerateApiAccessorCall(
           RelocInfo::EXTERNAL_REFERENCE);
 
   // Jump to stub.
-  CallApiCallbackStub stub(isolate, is_store, !optimization.is_constant_call());
+  CallApiCallbackStub stub(isolate, is_store);
   __ TailCallStub(&stub);
 }
 

src/mips/code-stubs-mips.cc

@@ -1573,7 +1573,6 @@ static void CallApiFunctionAndReturn(MacroAssembler* masm,
 
 void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- a0                  : callee
   //  -- t0                  : call_data
   //  -- a2                  : holder
   //  -- a1                  : api_function_address
@@ -1585,11 +1584,9 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   //  -- sp[argc * 4]        : receiver
   // -----------------------------------
 
-  Register callee = a0;
   Register call_data = t0;
   Register holder = a2;
   Register api_function_address = a1;
-  Register context = cp;
 
   typedef FunctionCallbackArguments FCA;
 
@@ -1615,12 +1612,6 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // Push isolate and holder.
   __ Push(scratch, holder);
 
-  // Enter a new context
-  if (!is_lazy()) {
-    // Load context from callee.
-    __ lw(context, FieldMemOperand(callee, JSFunction::kContextOffset));
-  }
-
   // Prepare arguments.
   __ mov(scratch, sp);
 

src/mips/interface-descriptors-mips.cc

@@ -276,10 +276,10 @@ void ArgumentAdaptorDescriptor::InitializePlatformSpecific(
 void ApiCallbackDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
-      a0,  // callee
-      t0,  // call_data
-      a2,  // holder
-      a1,  // api_function_address
+      JavaScriptFrame::context_register(),  // callee context
+      t0,                                   // call_data
+      a2,                                   // holder
+      a1,                                   // api_function_address
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/mips64/code-stubs-mips64.cc

@@ -1575,7 +1575,6 @@ static void CallApiFunctionAndReturn(MacroAssembler* masm,
 
 void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- a0                  : callee
   //  -- a4                  : call_data
   //  -- a2                  : holder
   //  -- a1                  : api_function_address
@@ -1587,11 +1586,9 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   //  -- sp[argc * 8]        : receiver
   // -----------------------------------
 
-  Register callee = a0;
   Register call_data = a4;
   Register holder = a2;
   Register api_function_address = a1;
-  Register context = cp;
 
   typedef FunctionCallbackArguments FCA;
 
@@ -1617,12 +1614,6 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // Push isolate and holder.
   __ Push(scratch, holder);
 
-  // Enter a new context
-  if (!is_lazy()) {
-    // Load context from callee.
-    __ Ld(context, FieldMemOperand(callee, JSFunction::kContextOffset));
-  }
-
   // Prepare arguments.
   __ mov(scratch, sp);
 

src/mips64/interface-descriptors-mips64.cc

@@ -276,10 +276,10 @@ void ArgumentAdaptorDescriptor::InitializePlatformSpecific(
 void ApiCallbackDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
-      a0,  // callee
-      a4,  // call_data
-      a2,  // holder
-      a1,  // api_function_address
+      JavaScriptFrame::context_register(),  // callee context
+      a4,                                   // call_data
+      a2,                                   // holder
+      a1,                                   // api_function_address
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/ppc/code-stubs-ppc.cc

@@ -1576,7 +1576,6 @@ static void CallApiFunctionAndReturn(MacroAssembler* masm,
 
 void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- r3                  : callee
   //  -- r7                  : call_data
   //  -- r5                  : holder
   //  -- r4                  : api_function_address
@@ -1588,11 +1587,9 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   //  -- sp[argc * 4]        : receiver
   // -----------------------------------
 
-  Register callee = r3;
   Register call_data = r7;
   Register holder = r5;
   Register api_function_address = r4;
-  Register context = cp;
 
   typedef FunctionCallbackArguments FCA;
 
@@ -1622,12 +1619,6 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // holder
   __ push(holder);
 
-  // Enter a new context
-  if (!is_lazy()) {
-    // Load context from callee
-    __ LoadP(context, FieldMemOperand(callee, JSFunction::kContextOffset));
-  }
-
   // Prepare arguments.
   __ mr(scratch, sp);
 

src/ppc/interface-descriptors-ppc.cc

@@ -276,10 +276,10 @@ void ArgumentAdaptorDescriptor::InitializePlatformSpecific(
 void ApiCallbackDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
-      r3,  // callee
-      r7,  // call_data
-      r5,  // holder
-      r4,  // api_function_address
+      JavaScriptFrame::context_register(),  // callee context
+      r7,                                   // call_data
+      r5,                                   // holder
+      r4,                                   // api_function_address
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/s390/code-stubs-s390.cc

@@ -1577,7 +1577,6 @@ static void CallApiFunctionAndReturn(MacroAssembler* masm,
 
 void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- r2                  : callee
   //  -- r6                  : call_data
   //  -- r4                  : holder
   //  -- r3                  : api_function_address
@@ -1589,11 +1588,9 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   //  -- sp[argc * 4]        : receiver
   // -----------------------------------
 
-  Register callee = r2;
   Register call_data = r6;
   Register holder = r4;
   Register api_function_address = r3;
-  Register context = cp;
 
   typedef FunctionCallbackArguments FCA;
 
@@ -1623,12 +1620,6 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // holder
   __ push(holder);
 
-  // Enter a new context
-  if (!is_lazy()) {
-    // Load context from callee
-    __ LoadP(context, FieldMemOperand(callee, JSFunction::kContextOffset));
-  }
-
   // Prepare arguments.
   __ LoadRR(scratch, sp);
 

src/s390/interface-descriptors-s390.cc

@@ -269,10 +269,10 @@ void ArgumentAdaptorDescriptor::InitializePlatformSpecific(
 void ApiCallbackDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
-      r2,  // callee
-      r6,  // call_data
-      r4,  // holder
-      r3,  // api_function_address
+      JavaScriptFrame::context_register(),  // callee context
+      r6,                                   // call_data
+      r4,                                   // holder
+      r3,                                   // api_function_address
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }

src/x64/code-stubs-x64.cc

@@ -1467,7 +1467,6 @@ static void CallApiFunctionAndReturn(MacroAssembler* masm,
 
 void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // ----------- S t a t e -------------
-  //  -- rdi                 : callee
   //  -- rbx                 : call_data
   //  -- rcx                 : holder
   //  -- rdx                 : api_function_address
@@ -1480,11 +1479,9 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   //  -- rsp[(argc + 1) * 8] : receiver
   // -----------------------------------
 
-  Register callee = rdi;
   Register call_data = rbx;
   Register holder = rcx;
   Register api_function_address = rdx;
-  Register context = rsi;
   Register return_address = r8;
 
   typedef FunctionCallbackArguments FCA;
@@ -1516,12 +1513,7 @@ void CallApiCallbackStub::Generate(MacroAssembler* masm) {
   // holder
   __ Push(holder);
 
-  // enter a new context
   int argc = this->argc();
-  if (!this->is_lazy()) {
-    // load context from callee
-    __ movp(context, FieldOperand(callee, JSFunction::kContextOffset));
-  }
 
   __ movp(scratch, rsp);
   // Push return address back on stack.

src/x64/interface-descriptors-x64.cc

@@ -281,10 +281,10 @@ void ArgumentAdaptorDescriptor::InitializePlatformSpecific(
 void ApiCallbackDescriptor::InitializePlatformSpecific(
     CallInterfaceDescriptorData* data) {
   Register registers[] = {
-      rdi,  // callee
-      rbx,  // call_data
-      rcx,  // holder
-      rdx,  // api_function_address
+      JavaScriptFrame::context_register(),  // callee context
+      rbx,                                  // call_data
+      rcx,                                  // holder
+      rdx,                                  // api_function_address
   };
   data->InitializePlatformSpecific(arraysize(registers), registers);
 }