VM: Implement closure calls as instance calls.

runtime/vm/stub_code_x64.cc

Index: runtime/vm/stub_code_x64.cc
===================================================================
--- runtime/vm/stub_code_x64.cc	(revision 34916)
+++ runtime/vm/stub_code_x64.cc	(working copy)
@@ -693,81 +693,6 @@
 }
 
 
-// Input parameters:
-//   R10: Arguments descriptor array.
-// Note: The closure object is the first argument to the function being
-//       called, the stub accesses the closure from this location directly
-//       when trying to resolve the call.
-void StubCode::GenerateCallClosureFunctionStub(Assembler* assembler) {
-  // Load num_args.
-  __ movq(RAX, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
-  // Load closure object in R13.
-  __ movq(R13, Address(RSP, RAX, TIMES_4, 0));  // RAX is a Smi.
-
-  __ LoadObject(R12, Object::null_object(), PP);
-
-  // Verify that R13 is a closure by checking its class.
-  Label not_closure;
-  __ cmpq(R13, R12);
-  // Not a closure, but null object.
-  __ j(EQUAL, &not_closure);
-  __ testq(R13, Immediate(kSmiTagMask));
-  __ j(ZERO, &not_closure);  // Not a closure, but a smi.
-  // Verify that the class of the object is a closure class by checking that
-  // class.signature_function() is not null.
-  __ LoadClass(RAX, R13);
-  __ movq(RAX, FieldAddress(RAX, Class::signature_function_offset()));
-  __ cmpq(RAX, R12);
-  // Actual class is not a closure class.
-  __ j(EQUAL, &not_closure, Assembler::kNearJump);
-
-  // RAX is just the signature function. Load the actual closure function.
-  __ movq(RAX, FieldAddress(R13, Closure::function_offset()));
-
-  // Load closure context in CTX; note that CTX has already been preserved.
-  __ movq(CTX, FieldAddress(R13, Closure::context_offset()));
-
-  // Load closure function code in RAX.
-  __ movq(RCX, FieldAddress(RAX, Function::code_offset()));
-
-  // RAX: Function.
-  // R10: Arguments descriptor array.
-  // RBX: Smi 0 (no IC data; the lazy-compile stub expects a GC-safe value).
-  __ xorq(RBX, RBX);
-  __ movq(RCX, FieldAddress(RCX, Code::instructions_offset()));
-  __ addq(RCX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
-  __ jmp(RCX);
-
-  __ Bind(&not_closure);
-  // Call runtime to attempt to resolve and invoke a call method on a
-  // non-closure object, passing the non-closure object and its arguments array,
-  // returning here.
-  // If no call method exists, throw a NoSuchMethodError.
-  // R13: non-closure object.
-  // R10: arguments descriptor array.
-
-  // Create a stub frame as we are pushing some objects on the stack before
-  // calling into the runtime.
-  __ EnterStubFrame();
-  // Setup space on stack for result from call.
-  __ pushq(R12);
-  __ pushq(R10);  // Arguments descriptor.
-  // Load smi-tagged arguments array length, including the non-closure.
-  __ movq(R10, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
-  PushArgumentsArray(assembler);
-
-  __ CallRuntime(kInvokeNonClosureRuntimeEntry, 2);
-
-  // Remove arguments.
-  __ Drop(2);
-  __ popq(RAX);  // Get result into RAX.
-
-  // Remove the stub frame as we are about to return.
-  __ LeaveStubFrame();
-  __ ret();
-}
-
-
 // Called when invoking Dart code from C++ (VM code).
 // Input parameters:
 //   RSP : points to return address.