Push raw_null instead of smi 0 in all places were we setup the return value location before calli...

vm/stub_code_x64.cc

 // Copyright (c) 2011, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/code_generator.h"
 #include "vm/compiler.h"
 #include "vm/ic_data.h"
@@ skipping 368 matching lines @@
   // TOS + 2: Last argument of caller.
   // ....
   // Total number of args is the first Smi in args descriptor array (R10).
   __ movq(RAX, FieldAddress(R10, Array::data_offset()));
   __ movq(RAX, Address(RSP, RAX, TIMES_4, kWordSize));  // Get receiver.
   __ pushq(R10);  // Preserve arguments descriptor array.
   __ pushq(RAX);  // Preserve receiver.
   __ pushq(RBX);  // Preserve ic-data array.
   // First resolve the function to get the function object.
 
-  // Setup space for return value on stack by pushing smi 0.
-  __ pushq(Immediate(0));
+  __ pushq(raw_null);  // Setup space on stack for return value.
   __ pushq(RAX);  // Push receiver.
   __ CallRuntimeFromStub(kResolveCompileInstanceFunctionRuntimeEntry);
   __ popq(RAX);  // Remove receiver pushed earlier.
   __ popq(RBX);  // Pop returned code object into RBX.
   // Pop preserved values
   __ popq(R10);  // Restore ic-data array.
   __ popq(RAX);  // Restore receiver.
   __ popq(R13);  // Restore arguments descriptor array.
 
   __ cmpq(RBX, raw_null);
@@ skipping 14 matching lines @@
   // RBX: raw_null.
   // R13: arguments descriptor array.
   // The target function was not found.
   // First check to see if this is a getter function and we are
   // trying to create a closure of an instance function.
   // Push values that need to be preserved across runtime call.
   __ pushq(RAX);  // Preserve receiver.
   __ pushq(R10);  // Preserve ic-data array.
   __ pushq(R13);  // Preserve arguments descriptor array.
 
-  __ pushq(Immediate(0));
+  __ pushq(raw_null);  // Setup space on stack for return value.
   __ pushq(RAX);  // Push receiver.
   __ pushq(R10);  // Ic-data array.
   __ CallRuntimeFromStub(kResolveImplicitClosureFunctionRuntimeEntry);
   __ popq(RAX);
   __ popq(RAX);
   __ popq(RBX);  // Get return value into RBX, might be Closure object.
 
   // Pop preserved values.
   __ popq(R13);  // Restore arguments descriptor array.
   __ popq(R10);  // Restore ic-data array.
@@ skipping 14 matching lines @@
   // RBX: raw_null.
   // R13: arguments descriptor array.
   // This is not the case of an instance so invoke the getter of the
   // same name and see if we get a closure back which we are then
   // supposed to invoke.
   // Push values that need to be preserved across runtime call.
   __ pushq(RAX);  // Preserve receiver.
   __ pushq(R10);  // Preserve ic-data array.
   __ pushq(R13);  // Preserve arguments descriptor array.
 
-  __ pushq(Immediate(0));
+  __ pushq(raw_null);  // Setup space on stack for return value.
   __ pushq(RAX);  // Push receiver.
   __ pushq(R10);  // Ic-data array.
   __ CallRuntimeFromStub(kResolveImplicitClosureThroughGetterRuntimeEntry);
   __ popq(R10);  // Pop argument.
   __ popq(RAX);  // Pop argument.
   __ popq(RBX);  // get return value into RBX, might be Closure object.
 
   // Pop preserved values.
   __ popq(R13);  // Restore arguments descriptor array.
   __ popq(R10);  // Restore ic-data array.
   __ popq(RAX);  // Restore receiver.
 
   __ cmpq(RBX, raw_null);
   Label function_not_found;
-  __ j(EQUAL, &function_not_found, Assembler::kNearJump);
+  __ j(EQUAL, &function_not_found);
 
   // RBX: Closure object.
   // R13: Arguments descriptor array.
-  __ pushq(Immediate(0));  // Result from invoking Closure.
+  __ pushq(raw_null);  // Setup space on stack for result from invoking Closure.
   __ pushq(RBX);  // Closure object.
   __ pushq(R13);  // Arguments descriptor.
   __ movq(R13, FieldAddress(R13, Array::data_offset()));
   __ SmiUntag(R13);
   __ subq(R13, Immediate(1));  // Arguments array length, minus the receiver.
   PushArgumentsArray(assembler, (kWordSize * 5));
   // Stack layout explaining "(kWordSize * 5)" offset.
   // TOS + 0: Argument array.
   // TOS + 1: Arguments descriptor array.
   // TOS + 2: Closure object.
@@ skipping 15 matching lines @@
   __ ret();
 
   __ Bind(&function_not_found);
   // The target function was not found, so invoke method
   // "void noSuchMethod(function_name, args_array)".
   //   RAX: receiver.
   //   R10: ic-data array.
   //   RBX: raw_null.
   //   R13: argument descriptor array.
 
-  // Setup space for return value on stack by pushing smi 0.
-  __ pushq(Immediate(0));  // Result from noSuchMethod.
+  __ pushq(raw_null);  // Setup space on stack for result from noSuchMethod.
   __ pushq(RAX);  // Receiver.
   __ pushq(R10);  // IC-data array.
   __ pushq(R13);  // Argument descriptor array.
   __ movq(R13, FieldAddress(R13, Array::data_offset()));
   __ SmiUntag(R13);
   __ subq(R13, Immediate(1));  // Arguments array length, minus the receiver.
   // See stack layout below explaining "wordSize * 6" offset.
   PushArgumentsArray(assembler, (kWordSize * 6));
 
   // Stack:
@@ skipping 119 matching lines @@
 
     // Done allocating and initializing the array.
     // RAX: new object.
     __ ret();
   }
 
   // Unable to allocate the array using the fast inline code, just call
   // into the runtime.
   __ Bind(&slow_case);
   __ EnterFrame(0);
-  __ pushq(raw_null);  // Push Null object for return value.
+  __ pushq(raw_null);  // Setup space on stack for return value.
   __ pushq(R10);  // Array length as Smi.
   __ pushq(RBX);  // Element type.
   __ pushq(raw_null);  // Null instantiator.
   __ CallRuntimeFromStub(kAllocateArrayRuntimeEntry);
   __ popq(RAX);  // Pop instantiator.
   __ popq(RAX);  // Pop element type argument.
   __ popq(R10);  // Pop array length argument.
   __ popq(RAX);  // Pop return value from return slot.
   __ LeaveFrame();
   __ ret();
@@ skipping 129 matching lines @@
 // RBX and RDX are destroyed.
 void StubCode::GenerateAllocateContextStub(Assembler* assembler) {
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
   if (false) {
     // TODO(regis): Implement fast inline allocation of contexts.
     __ Unimplemented("AllocateContext stub - inline allocation");
   }
   // Create the stub frame.
   __ EnterFrame(0);
-  __ pushq(raw_null);  // Make space for the return value.
+  __ pushq(raw_null);  // Setup space on stack for the return value.
   __ SmiTag(RDX);
   __ pushq(RDX);  // Push number of context variables.
   __ CallRuntimeFromStub(kAllocateContextRuntimeEntry);  // Allocate context.
   __ popq(RAX);  // Pop number of context variables argument.
   __ popq(RAX);  // Pop the new context object.
   // RAX: new object
   // Restore the frame pointer.
   __ LeaveFrame();
   __ ret();
 }
@@ skipping 164 matching lines @@
     __ ret();
 
     __ Bind(&slow_case);
   }
   if (is_cls_parameterized) {
     __ movq(RAX, Address(RSP, kObjectTypeArgumentsOffset));
     __ movq(RDX, Address(RSP, kInstantiatorTypeArgumentsOffset));
   }
   // Create a stub frame.
   __ EnterFrame(0);
-  const Object& new_object = Object::ZoneHandle();
-  __ PushObject(new_object);  // Push Null object for return value.
+  __ pushq(raw_null);  // Setup space on stack for return value.
   __ PushObject(cls);  // Push class of object to be allocated.
   if (is_cls_parameterized) {
     __ pushq(RAX);  // Push type arguments of object to be allocated.
     __ pushq(RDX);  // Push type arguments of instantiator.
   } else {
     __ pushq(raw_null);  // Push null type arguments.
     __ pushq(raw_null);  // Push null instantiator.
   }
   __ CallRuntimeFromStub(kAllocateObjectRuntimeEntry);  // Allocate object.
   __ popq(RAX);  // Pop argument (instantiator).
@@ skipping 33 matching lines @@
     __ Unimplemented("AllocateClosure stub - inline allocation");
   }
   if (has_type_arguments) {
     __ movq(RCX, Address(RSP, kTypeArgumentsOffset));
   }
   if (is_implicit_instance_closure) {
     __ movq(RAX, Address(RSP, kReceiverOffset));
   }
   // Create the stub frame.
   __ EnterFrame(0);
-  __ pushq(raw_null);  // Make space for the return value.
+  __ pushq(raw_null);  // Setup space on stack for the return value.
   __ PushObject(func);
   if (is_implicit_static_closure) {
     __ CallRuntimeFromStub(kAllocateImplicitStaticClosureRuntimeEntry);
   } else {
     if (is_implicit_instance_closure) {
       __ pushq(RAX);  // Receiver.
     }
     if (has_type_arguments) {
       __ pushq(RCX);  // Push type arguments of closure to be allocated.
     } else {
@@ skipping 87 matching lines @@
     __ call(&get_class);
     __ cmpq(RAX, R13);  // Match?
     __ j(NOT_EQUAL, &no_match, Assembler::kNearJump);
     // Check second.
     __ movq(R13, Address(R12, kWordSize));  // Get class from IC data to check.
     // Get next argument.
     __ movq(RAX, FieldAddress(R10, Array::data_offset()));
     __ movq(RAX, Address(RSP, RAX, TIMES_4, -kWordSize));  // RAX is Smi.
     __ call(&get_class);
     __ cmpq(RAX, R13);  // Match?
-    __ j(EQUAL, &found, Assembler::kNearJump);
+    __ j(EQUAL, &found);
     __ Bind(&no_match);
     __ addq(R12, Immediate(kWordSize * (1 + num_args)));  // Next element.
     __ cmpq(R13, raw_null);   // Done?
     __ j(NOT_EQUAL, &loop, Assembler::kNearJump);
   }
 
   __ Bind(&ic_miss);
   // Get receiver, again.
   __ movq(RAX, FieldAddress(R10, Array::data_offset()));
   __ leaq(RAX, Address(RSP, RAX, TIMES_4, 0));  // RAX is Smi.
   __ EnterFrame(0);
-  // Setup space for return value on stack by pushing smi 0.
   __ pushq(R10);  // Preserve arguments array.
   __ pushq(RBX);  // Preserve IC data array
-  __ pushq(Immediate(0));  // Space for result (target code object).
+  __ pushq(raw_null);  // Setup space on stack for result (target code object).
   __ movq(R10, FieldAddress(R10, Array::data_offset()));
   // Push call arguments.
   for (intptr_t i = 0; i < num_args; i++) {
     __ movq(R10, Address(RAX, -kWordSize * i));
     __ pushq(R10);
   }
   if (num_args == 1) {
     __ CallRuntimeFromStub(kInlineCacheMissHandlerOneArgRuntimeEntry);
   } else if (num_args == 2) {
     __ CallRuntimeFromStub(kInlineCacheMissHandlerTwoArgsRuntimeEntry);
@@ skipping 67 matching lines @@
 }
 
 
 void StubCode::GenerateBreakpointDynamicStub(Assembler* assembler) {
   __ Unimplemented("BreakpointDynamic stub");
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64