X87: [Interpreter] Add support for parameter variables.

src/x87/builtins-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/code-factory.h"
 #include "src/codegen.h"
 #include "src/deoptimizer.h"
 #include "src/full-codegen/full-codegen.h"
@@ skipping 734 matching lines @@
   // TODO(rmcilroy): List of things not currently dealt with here but done in
   // fullcodegen's EmitReturnSequence.
   //  - Supporting FLAG_trace for Runtime::TraceExit.
   //  - Support profiler (specifically decrementing profiling_counter
   //    appropriately and calling out to HandleInterrupts if necessary).
 
   // The return value is in accumulator, which is already in rax.
 
   // Leave the frame (also dropping the register file).
   __ leave();
-  // Return droping receiver + arguments.
-  // TODO(rmcilroy): Get number of arguments from BytecodeArray.
-  __ Ret(1 * kPointerSize, ecx);
+
+  // Drop receiver + arguments and return.
+  __ mov(ebx, FieldOperand(kInterpreterBytecodeArrayRegister,
+                           BytecodeArray::kParameterSizeOffset));
+  __ pop(ecx);
+  __ add(esp, ebx);
+  __ push(ecx);
+  __ ret(0);
 }
 
 
 void Builtins::Generate_CompileLazy(MacroAssembler* masm) {
   CallRuntimePassFunction(masm, Runtime::kCompileLazy);
   GenerateTailCallToReturnedCode(masm);
 }
 
 
 
@@ skipping 1016 matching lines @@
 
   __ bind(&ok);
   __ ret(0);
 }
 
 #undef __
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_X87