Pass closure object as first implicit argument to closure functions.

runtime/vm/flow_graph_compiler_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"  // Needed here to get TARGET_ARCH_X64.
 #if defined(TARGET_ARCH_X64)
 
 #include "vm/flow_graph_compiler.h"
 
 #include "lib/error.h"
@@ skipping 609 matching lines @@
   Definition* defn = instr->AsDefinition();
   if ((defn != NULL) && defn->is_used()) {
     __ pushq(defn->locs()->out().reg());
   }
 }
 
 
 void FlowGraphCompiler::CopyParameters() {
   __ Comment("Copy parameters");
   const Function& function = parsed_function().function();
-  const bool is_native_instance_closure =
-      function.is_native() && function.IsImplicitInstanceClosureFunction();
   LocalScope* scope = parsed_function().node_sequence()->scope();
   const int num_fixed_params = function.num_fixed_parameters();
   const int num_opt_pos_params = function.NumOptionalPositionalParameters();
-  int num_opt_named_params = function.NumOptionalNamedParameters();
+  const int num_opt_named_params = function.NumOptionalNamedParameters();
   const int num_params =
       num_fixed_params + num_opt_pos_params + num_opt_named_params;
-  int implicit_this_param_pos = is_native_instance_closure ? -1 : 0;
+  ASSERT(function.NumParameters() == num_params);
   ASSERT(parsed_function().first_parameter_index() ==
-         ParsedFunction::kFirstLocalSlotIndex + implicit_this_param_pos);
+         ParsedFunction::kFirstLocalSlotIndex);
 
   // Check that min_num_pos_args <= num_pos_args <= max_num_pos_args,
   // where num_pos_args is the number of positional arguments passed in.
   const int min_num_pos_args = num_fixed_params;
   const int max_num_pos_args = num_fixed_params + num_opt_pos_params;
 
   // Number of positional args is the second Smi in descriptor array (R10).
   __ movq(RCX, FieldAddress(R10, Array::data_offset() + (1 * kWordSize)));
   // Check that min_num_pos_args <= num_pos_args.
   Label wrong_num_arguments;
@@ skipping 10 matching lines @@
   // Total number of args is the first Smi in args descriptor array (R10).
   __ movq(RBX, FieldAddress(R10, Array::data_offset()));
   // Since RBX and RCX are Smi, use TIMES_4 instead of TIMES_8.
   // Let RBX point to the last passed positional argument, i.e. to
   // fp[1 + num_args - (num_pos_args - 1)].
   __ subq(RBX, RCX);
   __ leaq(RBX, Address(RBP, RBX, TIMES_4, 2 * kWordSize));
 
   // Let RDI point to the last copied positional argument, i.e. to
   // fp[ParsedFunction::kFirstLocalSlotIndex - (num_pos_args - 1)].
-  const int index =
-      ParsedFunction::kFirstLocalSlotIndex + 1 + implicit_this_param_pos;
-  // First copy captured receiver if function is an implicit native closure.
-  if (is_native_instance_closure) {
-    __ movq(RAX, FieldAddress(CTX, Context::variable_offset(0)));
-    __ movq(Address(RBP, (index * kWordSize)), RAX);
-  }
+  const int index = ParsedFunction::kFirstLocalSlotIndex + 1;
   __ SmiUntag(RCX);
   __ movq(RAX, RCX);
   __ negq(RAX);
   // -num_pos_args is in RAX.
-  // (ParsedFunction::kFirstLocalSlotIndex + 1 + implicit_this_param_pos)
-  // is in index.
+  // (ParsedFunction::kFirstLocalSlotIndex + 1) is in index.
   __ leaq(RDI, Address(RBP, RAX, TIMES_8, (index * kWordSize)));
   Label loop, loop_condition;
   __ jmp(&loop_condition, Assembler::kNearJump);
   // We do not use the final allocation index of the variable here, i.e.
   // scope->VariableAt(i)->index(), because captured variables still need
   // to be copied to the context that is not yet allocated.
   const Address argument_addr(RBX, RCX, TIMES_8, 0);
   const Address copy_addr(RDI, RCX, TIMES_8, 0);
   __ Bind(&loop);
   __ movq(RAX, argument_addr);
@@ skipping 55 matching lines @@
       // Load RAX with default argument.
       const Object& value = Object::ZoneHandle(
           parsed_function().default_parameter_values().At(
               param_pos - num_fixed_params));
       __ LoadObject(RAX, value);
       __ Bind(&assign_optional_parameter);
       // Assign RAX to fp[ParsedFunction::kFirstLocalSlotIndex - param_pos].
       // We do not use the final allocation index of the variable here, i.e.
       // scope->VariableAt(i)->index(), because captured variables still need
       // to be copied to the context that is not yet allocated.
-      intptr_t computed_param_pos = (ParsedFunction::kFirstLocalSlotIndex -
-                                     param_pos + implicit_this_param_pos);
+      const intptr_t computed_param_pos =
+          ParsedFunction::kFirstLocalSlotIndex - param_pos;
       const Address param_addr(RBP, (computed_param_pos * kWordSize));
       __ movq(param_addr, RAX);
       __ Bind(&next_parameter);
     }
     delete[] opt_param;
     delete[] opt_param_position;
     // Check that RDI now points to the null terminator in the array descriptor.
     __ cmpq(Address(RDI, 0), raw_null);
     __ j(EQUAL, &all_arguments_processed, Assembler::kNearJump);
-  } else if (num_opt_pos_params > 0) {
+  } else {
+    ASSERT(num_opt_pos_params > 0);
     // Number of positional args is the second Smi in descriptor array (R10).
     __ movq(RCX, FieldAddress(R10, Array::data_offset() + (1 * kWordSize)));
     __ SmiUntag(RCX);
     for (int i = 0; i < num_opt_pos_params; i++) {
       Label next_parameter;
       // Handle this optional positonal parameter only if k or fewer positional
       // arguments have been passed, where k is param_pos, the position of this
       // optional parameter in the formal parameter list.
       const int param_pos = num_fixed_params + i;
       __ cmpq(RCX, Immediate(param_pos));
       __ j(GREATER, &next_parameter, Assembler::kNearJump);
       // Load RAX with default argument.
       const Object& value = Object::ZoneHandle(
           parsed_function().default_parameter_values().At(i));
       __ LoadObject(RAX, value);
       // Assign RAX to fp[ParsedFunction::kFirstLocalSlotIndex - param_pos].
       // We do not use the final allocation index of the variable here, i.e.
       // scope->VariableAt(i)->index(), because captured variables still need
       // to be copied to the context that is not yet allocated.
-      intptr_t computed_param_pos = (ParsedFunction::kFirstLocalSlotIndex -
-                                     param_pos + implicit_this_param_pos);
+      const intptr_t computed_param_pos =
+          ParsedFunction::kFirstLocalSlotIndex - param_pos;
       const Address param_addr(RBP, (computed_param_pos * kWordSize));
       __ movq(param_addr, RAX);
       __ Bind(&next_parameter);
     }
     // Total number of args is the first Smi in args descriptor array (R10).
     __ movq(RBX, FieldAddress(R10, Array::data_offset()));
     __ SmiUntag(RBX);
     // Check that RCX equals RBX, i.e. no named arguments passed.
     __ cmpq(RCX, RBX);
     __ j(EQUAL, &all_arguments_processed, Assembler::kNearJump);
-  } else {
-    ASSERT(is_native_instance_closure);
-    __ jmp(&all_arguments_processed, Assembler::kNearJump);
   }
 
   __ Bind(&wrong_num_arguments);
   if (StackSize() != 0) {
     // We need to unwind the space we reserved for locals and copied parameters.
     // The NoSuchMethodFunction stub does not expect to see that area on the
     // stack.
     __ addq(RSP, Immediate(StackSize() * kWordSize));
   }
   // The calls immediately below have empty stackmaps because we have just
@@ skipping 551 matching lines @@
 void ParallelMoveResolver::Exchange(const Address& mem1, const Address& mem2) {
   __ Exchange(mem1, mem2);
 }
 
 
 #undef __
 
 }  // namespace dart
 
 #endif  // defined TARGET_ARCH_X64