X87: [stubs] Simplify the non-function case of CallConstructStub.

src/x87/code-stubs-x87.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_X87
 
 #include "src/base/bits.h"
 #include "src/bootstrapper.h"
 #include "src/code-stubs.h"
 #include "src/codegen.h"
@@ skipping 1867 matching lines @@
   __ mov(jmp_reg, FieldOperand(edi, JSFunction::kSharedFunctionInfoOffset));
   __ mov(jmp_reg, FieldOperand(jmp_reg,
                                SharedFunctionInfo::kConstructStubOffset));
   __ lea(jmp_reg, FieldOperand(jmp_reg, Code::kHeaderSize));
   __ jmp(jmp_reg);
 
   // edi: called object
   // eax: number of arguments
   // ecx: object map
   // esp[0]: original receiver (for IsSuperConstructorCall)
-  Label do_call;
   __ bind(&slow);
-  __ CmpInstanceType(ecx, JS_FUNCTION_PROXY_TYPE);
-  __ j(not_equal, &non_function_call);
-  __ GetBuiltinEntry(edx,
-                     Context::CALL_FUNCTION_PROXY_AS_CONSTRUCTOR_BUILTIN_INDEX);
-  __ jmp(&do_call);
+  {
+    __ CmpInstanceType(ecx, JS_FUNCTION_PROXY_TYPE);
+    __ j(not_equal, &non_function_call, Label::kNear);
+    if (IsSuperConstructorCall()) __ Drop(1);
+    // TODO(neis): This doesn't match the ES6 spec for [[Construct]] on proxies.
+    __ mov(edi, FieldOperand(edi, JSFunctionProxy::kConstructTrapOffset));
+    __ Jump(isolate()->builtins()->Call(), RelocInfo::CODE_TARGET);
 
-  __ bind(&non_function_call);
-  __ GetBuiltinEntry(edx,
-                     Context::CALL_NON_FUNCTION_AS_CONSTRUCTOR_BUILTIN_INDEX);
-  __ bind(&do_call);
-  if (IsSuperConstructorCall()) {
-    __ Drop(1);
+    __ bind(&non_function_call);
+    if (IsSuperConstructorCall()) __ Drop(1);
+    {
+      // Determine the delegate for the target (if any).
+      FrameScope scope(masm, StackFrame::INTERNAL);
+      __ SmiTag(eax);
+      __ Push(eax);
+      __ Push(edi);
+      __ CallRuntime(Runtime::kGetConstructorDelegate, 1);
+      __ mov(edi, eax);
+      __ Pop(eax);
+      __ SmiUntag(eax);
+    }
+    // The delegate is always a regular function.
+    __ AssertFunction(edi);
+    __ Jump(isolate()->builtins()->CallFunction(), RelocInfo::CODE_TARGET);
   }
-  // Set expected number of arguments to zero (not changing eax).
-  __ Move(ebx, Immediate(0));
-  Handle<Code> arguments_adaptor =
-      isolate()->builtins()->ArgumentsAdaptorTrampoline();
-  __ jmp(arguments_adaptor, RelocInfo::CODE_TARGET);
 }
 
 
 static void EmitLoadTypeFeedbackVector(MacroAssembler* masm, Register vector) {
   __ mov(vector, Operand(ebp, JavaScriptFrameConstants::kFunctionOffset));
   __ mov(vector, FieldOperand(vector, JSFunction::kSharedFunctionInfoOffset));
   __ mov(vector, FieldOperand(vector,
                               SharedFunctionInfo::kFeedbackVectorOffset));
 }
 
@@ skipping 3562 matching lines @@
                            Operand(ebp, 7 * kPointerSize), NULL);
 }
 
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87