Refactor the InstanceFunctionLookupStub.

runtime/vm/stub_code_x64.cc

 // Copyright (c) 2012, 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/assembler.h"
 #include "vm/assembler_macros.h"
 #include "vm/compiler.h"
@@ skipping 205 matching lines @@
   __ popq(R10);  // Restore arguments descriptor array.
   __ movq(RAX, FieldAddress(RAX, Code::instructions_offset()));
   __ addq(RAX, Immediate(Instructions::HeaderSize() - kHeapObjectTag));
   __ LeaveFrame();
   __ jmp(RAX);
   __ int3();
 }
 
 
 // Input parameters:
-//   R13: argument count, may be zero.
+//   R10: smi-tagged argument count, may be zero.
 static void PushArgumentsArray(Assembler* assembler, intptr_t arg_offset) {
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
 
   // Allocate array to store arguments of caller.
-  __ movq(R10, R13);  // Arguments array length.
-  __ SmiTag(R10);  // Convert to Smi.
   __ movq(RBX, raw_null);  // Null element type for raw Array.
   __ call(&StubCode::AllocateArrayLabel());
   __ SmiUntag(R10);
   // RAX: newly allocated array.
   // R10: length of the array (was preserved by the stub).
   __ pushq(RAX);  // Array is in RAX and on top of stack.
   __ leaq(R12, Address(RSP, R10, TIMES_8, arg_offset));  // Addr of first arg.
   __ leaq(RBX, FieldAddress(RAX, Array::data_offset()));
   Label loop, loop_condition;
   __ jmp(&loop_condition, Assembler::kNearJump);
   __ Bind(&loop);
   __ movq(RAX, Address(R12, 0));
   __ movq(Address(RBX, 0), RAX);
   __ AddImmediate(RBX, Immediate(kWordSize));
   __ AddImmediate(R12, Immediate(-kWordSize));
   __ Bind(&loop_condition);
   __ decq(R10);
   __ j(POSITIVE, &loop, Assembler::kNearJump);
 }
 
 
 // Input parameters:
 //   RBX: ic-data.
 //   R10: arguments descriptor array.
 // Note: The receiver object is the first argument to the function being
 //       called, the stub accesses the receiver from this location directly
 //       when trying to resolve the call.
 void StubCode::GenerateInstanceFunctionLookupStub(Assembler* assembler) {
+  AssemblerMacros::EnterStubFrame(assembler);
+
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
+  __ pushq(raw_null);  // Space for the return value.
 
-  // Create a stub frame as we are pushing some objects on the stack before
-  // calling into the runtime.
-  AssemblerMacros::EnterStubFrame(assembler);
+  // Push the receiver as an argument.  Load the smi-tagged argument
+  // count into R13 to index the receiver in the stack.  There are
+  // three words (null, stub's pc marker, saved fp) above the return
+  // address.
+  __ movq(R13, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
+  __ pushq(Address(RSP, R13, TIMES_4, (3 * kWordSize)));
 
-  // Preserve values across call to resolving.
-  // Stack at this point:
-  // TOS + 0: PC marker => RawInstruction object.
-  // TOS + 1: Saved RBP of previous frame. <== RBP
-  // TOS + 2: Dart code return address
-  // TOS + 3: Last argument of caller.
-  // ....
-  __ movq(RAX, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
-  __ movq(RAX, Address(RBP, RAX, TIMES_4, kWordSize));  // Get receiver.
-  // RAX: receiver.
-  // RBX: ic-data.
-  // R10: 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(RBX);  // Preserve ic-data.
-  __ pushq(R10);  // Preserve arguments descriptor array.
+  __ pushq(RBX);  // Pass IC data object.
+  __ pushq(R10);  // Pass arguments descriptor array.
 
-  __ pushq(raw_null);  // Setup space on stack for return value.
-  __ pushq(RAX);  // Push receiver.
-  __ pushq(RBX);  // Ic-data array.
-  __ CallRuntime(kResolveImplicitClosureFunctionRuntimeEntry);
-  __ popq(RAX);
-  __ popq(RAX);
-  __ popq(RCX);  // Get return value into RCX, might be Closure object.
-
-  // Pop preserved values.
-  __ popq(R10);  // Restore arguments descriptor array.
-  __ popq(RBX);  // Restore ic-data.
-  __ popq(RAX);  // Restore receiver.
-
-  __ cmpq(RCX, raw_null);
-  Label check_implicit_closure_through_getter;
-  __ j(EQUAL, &check_implicit_closure_through_getter, Assembler::kNearJump);
-
-  __ movq(RAX, RCX);  // Return value is the closure object.
-  // Remove the stub frame as we are about return.
-  __ LeaveFrame();
-  __ ret();
-
-  __ Bind(&check_implicit_closure_through_getter);
-  // RAX: receiver.
-  // RBX: ic-data.
-  // R10: 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(RBX);  // Preserve ic-data.
-  __ pushq(R10);  // Preserve arguments descriptor array.
-
-  __ pushq(raw_null);  // Setup space on stack for return value.
-  __ pushq(RAX);  // Push receiver.
-  __ pushq(RBX);  // Ic-data array.
-  __ CallRuntime(kResolveImplicitClosureThroughGetterRuntimeEntry);
-  __ popq(RAX);  // Pop argument.
-  __ popq(RAX);  // Pop argument.
-  __ popq(RCX);  // get return value into RCX, might be Closure object.
-
-  // Pop preserved values.
-  __ popq(R10);  // Restore arguments descriptor array.
-  __ popq(RBX);  // Restore ic-data.
-  __ popq(RAX);  // Restore receiver.
-
-  __ cmpq(RCX, raw_null);
-  Label function_not_found;
-  __ j(EQUAL, &function_not_found);
-
-  // RCX: Closure object.
-  // R10: Arguments descriptor array.
-  __ pushq(raw_null);  // Setup space on stack for result from invoking Closure.
-  __ pushq(RCX);  // Closure object.
-  __ pushq(R10);  // Arguments descriptor.
-  __ movq(R13, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
-  __ SmiUntag(R13);  // Arguments array length, including the original receiver.
-  PushArgumentsArray(assembler, (kWordSize * 6));
-  // Stack layout explaining "(kWordSize * 6)" offset.
-  // TOS + 0: Argument array.
-  // TOS + 1: Arguments descriptor array.
-  // TOS + 2: Closure object.
-  // TOS + 3: Place for result from closure function.
-  // TOS + 4: PC marker => RawInstruction object.
-  // TOS + 5: Saved RBP of previous frame. <== RBP
-  // TOS + 6: Dart code return address
-  // TOS + 7: Last argument of caller.
-  // ....
-
-  __ CallRuntime(kInvokeImplicitClosureFunctionRuntimeEntry);
-  // Remove arguments.
-  __ popq(RAX);
-  __ popq(RAX);
-  __ popq(RAX);
-  __ popq(RAX);  // Get result into RAX.
-
-  // Remove the stub frame as we are about to return.
-  __ LeaveFrame();
-  __ ret();
-
-  __ Bind(&function_not_found);
-  // The target function was not found, so invoke method
-  // "dynamic noSuchMethod(InvocationMirror invocation)".
-  //   RAX: receiver.
-  //   RBX: ic-data.
-  //   R10: arguments descriptor array.
-
-  __ pushq(raw_null);  // Setup space on stack for result from noSuchMethod.
-  __ pushq(RAX);  // Receiver.
-  __ pushq(RBX);  // IC-data array.
-  __ pushq(R10);  // Arguments descriptor array.
-  __ movq(R13, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
-  __ SmiUntag(R13);  // Arguments array length, including the original receiver.
-  // See stack layout below explaining "wordSize * 7" offset.
-  PushArgumentsArray(assembler, (kWordSize * 7));
-
-  // Stack:
+  // Pass the call's arguments array.
+  __ movq(R10, R13);  // Smi-tagged arguments array length.
+  PushArgumentsArray(assembler, (7 * kWordSize));
+  // Stack layout explaining "(7 * kWordSize)" offset.
   // TOS + 0: Arguments array.
   // TOS + 1: Arguments descriptor array.
-  // TOS + 2: IC-data array.
+  // TOS + 2: IC data object.
   // TOS + 3: Receiver.
-  // TOS + 4: Place for result from noSuchMethod.
-  // TOS + 5: PC marker => RawInstruction object.
-  // TOS + 6: Saved RBP of previous frame. <== RBP
+  // TOS + 4: Space for the result of the runtime call.
+  // TOS + 5: Stub's PC marker (0)
+  // TOS + 6: Saved FP
   // TOS + 7: Dart code return address
   // TOS + 8: Last argument of caller.
   // ....
 
-  __ CallRuntime(kInvokeNoSuchMethodFunctionRuntimeEntry);
+  __ CallRuntime(kInstanceFunctionLookupRuntimeEntry);
   // Remove arguments.
   __ popq(RAX);
   __ popq(RAX);
   __ popq(RAX);
   __ popq(RAX);
   __ popq(RAX);  // Get result into RAX.
-
-  // Remove the stub frame as we are about to return.
   __ LeaveFrame();
   __ ret();
 }
 
 
 DECLARE_LEAF_RUNTIME_ENTRY(intptr_t, DeoptimizeCopyFrame,
                            intptr_t deopt_reason,
                            uword saved_registers_address);
 
 DECLARE_LEAF_RUNTIME_ENTRY(void, DeoptimizeFillFrame, uword last_fp);
@@ skipping 108 matching lines @@
 void StubCode::GenerateDeoptimizeStub(Assembler* assembler) {
   GenerateDeoptimizationSequence(assembler, false);  // Don't preserve RAX.
 }
 
 
 void StubCode::GenerateMegamorphicMissStub(Assembler* assembler) {
   AssemblerMacros::EnterStubFrame(assembler);
   // Load the receiver into RAX.  The argument count in the arguments
   // descriptor in R10 is a smi.
   __ movq(RAX, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
-  // Two words (return addres, saved fp) in the stack above the last argument.
+  // Two words (saved fp, stub's pc marker) in the stack above the return
+  // address.
   __ movq(RAX, Address(RSP, RAX, TIMES_4, 2 * kWordSize));
   // Preserve IC data and arguments descriptor.
   __ pushq(RBX);
   __ pushq(R10);
 
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Instructions::null()));
   __ pushq(raw_null);  // Space for the result of the runtime call.
   __ pushq(RAX);  // Receiver.
   __ pushq(RBX);  // IC data.
@@ skipping 225 matching lines @@
   // 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.
   AssemblerMacros::EnterStubFrame(assembler);
 
   __ pushq(raw_null);  // Setup space on stack for result from call.
   __ pushq(R13);  // Non-closure object.
   __ pushq(R10);  // Arguments descriptor.
-  // Load num_args.
-  __ movq(R13, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
-  __ SmiUntag(R13);  // Arguments array length, including the non-closure.
+  // Load smi-tagged arguments array length, including the non-closure.
+  __ movq(R10, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
   // See stack layout below explaining "wordSize * 6" offset.
   PushArgumentsArray(assembler, (kWordSize * 6));
 
   // Stack:
   // TOS + 0: Argument array.
   // TOS + 1: Arguments descriptor array.
   // TOS + 2: Non-closure object.
   // TOS + 3: Place for result from the call.
   // TOS + 4: PC marker => RawInstruction object.
   // TOS + 5: Saved RBP of previous frame. <== RBP
@@ skipping 644 matching lines @@
 //   RBP + 16 : address of last argument (arg n-1).
 //   RBP + 16 + 8*(n-1) : address of first argument (arg 0).
 //   RBX : ic-data.
 //   R10 : arguments descriptor array.
 void StubCode::GenerateCallNoSuchMethodFunctionStub(Assembler* assembler) {
   // The target function was not found, so invoke method
   // "dynamic noSuchMethod(InvocationMirror invocation)".
   const Immediate raw_null =
       Immediate(reinterpret_cast<intptr_t>(Object::null()));
   __ movq(R13, FieldAddress(R10, ArgumentsDescriptor::count_offset()));
-  __ SmiUntag(R13);
-  __ movq(RAX, Address(RBP, R13, TIMES_8, kWordSize));  // Get receiver.
+  __ movq(RAX, Address(RBP, R13, TIMES_4, kWordSize));  // Get receiver.
 
   // Create a stub frame.
   AssemblerMacros::EnterStubFrame(assembler);
 
   __ pushq(raw_null);  // Setup space on stack for result from noSuchMethod.
   __ pushq(RAX);  // Receiver.
   __ pushq(RBX);  // IC data array.
   __ pushq(R10);  // Arguments descriptor array.
-  // R13: Arguments array length, including the receiver.
+
+  __ movq(R10, R13);  // Smi-tagged arguments array length.
   // See stack layout below explaining "wordSize * 10" offset.
   PushArgumentsArray(assembler, (kWordSize * 10));
 
   // Stack:
   // TOS + 0: Argument array.
   // TOS + 1: Arguments descriptor array.
   // TOS + 2: Ic-data array.
   // TOS + 3: Receiver.
   // TOS + 4: Place for result from noSuchMethod.
   // TOS + 5: PC marker => RawInstruction object.
@@ skipping 706 matching lines @@
   __ cmpq(left, right);
   __ Bind(&done);
   __ popq(right);
   __ popq(left);
   __ ret();
 }
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64