[turbofan] Do not force stack slot for eager deopt inputs.

src/compiler/instruction-selector.cc

 // Copyright 2014 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.
 
 #include "src/compiler/instruction-selector.h"
 
 #include <limits>
 
 #include "src/base/adapters.h"
 #include "src/compiler/instruction-selector-impl.h"
@@ skipping 342 matching lines @@
   // arg 1               : deoptimization id.
   // arg 2 - arg (n + 1) : value inputs to the frame state.
   if (buffer->frame_state_descriptor != NULL) {
     InstructionSequence::StateId state_id =
         sequence()->AddFrameStateDescriptor(buffer->frame_state_descriptor);
     buffer->instruction_args.push_back(g.TempImmediate(state_id.ToInt()));
 
     Node* frame_state =
         call->InputAt(static_cast<int>(buffer->descriptor->InputCount()));
     AddFrameStateInputs(frame_state, &buffer->instruction_args,
-                        buffer->frame_state_descriptor);
+                        buffer->frame_state_descriptor,
+                        FrameStateInputKind::kStackSlot);
   }
   DCHECK(1 + buffer->frame_state_value_count() ==
          buffer->instruction_args.size());
 
   size_t input_count = static_cast<size_t>(buffer->input_count());
 
   // Split the arguments into pushed_nodes and instruction_args. Pushed
   // arguments require an explicit push instruction before the call and do
   // not appear as arguments to the call. Everything else ends up
   // as an InstructionOperand argument to the call.
@@ skipping 635 matching lines @@
   FrameStateDescriptor* desc = GetFrameStateDescriptor(value);
   size_t arg_count = desc->GetTotalSize() + 1;  // Include deopt id.
 
   InstructionOperandVector args(instruction_zone());
   args.reserve(arg_count);
 
   InstructionSequence::StateId state_id =
       sequence()->AddFrameStateDescriptor(desc);
   args.push_back(g.TempImmediate(state_id.ToInt()));
 
-  AddFrameStateInputs(value, &args, desc);
+  AddFrameStateInputs(value, &args, desc, FrameStateInputKind::kAny);
 
   DCHECK_EQ(args.size(), arg_count);
 
   Emit(kArchDeoptimize, 0, nullptr, arg_count, &args.front(), 0, nullptr);
 }
 
 
 void InstructionSelector::VisitThrow(Node* value) {
   OperandGenerator g(this);
   Emit(kArchNop, g.NoOutput());  // TODO(titzer)
@@ skipping 22 matching lines @@
     outer_state = GetFrameStateDescriptor(outer_node);
   }
 
   return new (instruction_zone()) FrameStateDescriptor(
       instruction_zone(), state_info.type(), state_info.bailout_id(),
       state_info.state_combine(), parameters, locals, stack,
       state_info.shared_info(), outer_state);
 }
 
 
-static InstructionOperand SlotOrImmediate(OperandGenerator* g, Node* input) {
+InstructionOperand InstructionSelector::OperandForDeopt(
+    OperandGenerator* g, Node* input, FrameStateInputKind kind) {
   switch (input->opcode()) {
     case IrOpcode::kInt32Constant:
     case IrOpcode::kNumberConstant:
     case IrOpcode::kFloat64Constant:
     case IrOpcode::kHeapConstant:
       return g->UseImmediate(input);
     default:
-      return g->UseUniqueSlot(input);
+      switch (kind) {
+        case FrameStateInputKind::kStackSlot:
+          return g->UseUniqueSlot(input);
+        case FrameStateInputKind::kAny:
+          return g->Use(input);
+      }

[Benedikt Meurer, 2015/09/03 13:11:09]

Nit: Add UNREACHABLE() at the end.

   }
 }
 
 
-void InstructionSelector::AddFrameStateInputs(
-    Node* state, InstructionOperandVector* inputs,
-    FrameStateDescriptor* descriptor) {
+void InstructionSelector::AddFrameStateInputs(Node* state,
+                                              InstructionOperandVector* inputs,
+                                              FrameStateDescriptor* descriptor,
+                                              FrameStateInputKind kind) {
   DCHECK_EQ(IrOpcode::kFrameState, state->op()->opcode());
 
   if (descriptor->outer_state()) {
     AddFrameStateInputs(state->InputAt(kFrameStateOuterStateInput), inputs,
-                        descriptor->outer_state());
+                        descriptor->outer_state(), kind);
   }
 
   Node* parameters = state->InputAt(kFrameStateParametersInput);
   Node* locals = state->InputAt(kFrameStateLocalsInput);
   Node* stack = state->InputAt(kFrameStateStackInput);
   Node* context = state->InputAt(kFrameStateContextInput);
   Node* function = state->InputAt(kFrameStateFunctionInput);
 
   DCHECK_EQ(descriptor->parameters_count(),
             StateValuesAccess(parameters).size());
   DCHECK_EQ(descriptor->locals_count(), StateValuesAccess(locals).size());
   DCHECK_EQ(descriptor->stack_count(), StateValuesAccess(stack).size());
 
   ZoneVector<MachineType> types(instruction_zone());
   types.reserve(descriptor->GetSize());
 
   OperandGenerator g(this);
   size_t value_index = 0;
-  inputs->push_back(SlotOrImmediate(&g, function));
+  inputs->push_back(OperandForDeopt(&g, function, kind));
   descriptor->SetType(value_index++, kMachAnyTagged);
   for (StateValuesAccess::TypedNode input_node :
        StateValuesAccess(parameters)) {
-    inputs->push_back(SlotOrImmediate(&g, input_node.node));
+    inputs->push_back(OperandForDeopt(&g, input_node.node, kind));
     descriptor->SetType(value_index++, input_node.type);
   }
   if (descriptor->HasContext()) {
-    inputs->push_back(SlotOrImmediate(&g, context));
+    inputs->push_back(OperandForDeopt(&g, context, kind));
     descriptor->SetType(value_index++, kMachAnyTagged);
   }
   for (StateValuesAccess::TypedNode input_node : StateValuesAccess(locals)) {
-    inputs->push_back(SlotOrImmediate(&g, input_node.node));
+    inputs->push_back(OperandForDeopt(&g, input_node.node, kind));
     descriptor->SetType(value_index++, input_node.type);
   }
   for (StateValuesAccess::TypedNode input_node : StateValuesAccess(stack)) {
-    inputs->push_back(SlotOrImmediate(&g, input_node.node));
+    inputs->push_back(OperandForDeopt(&g, input_node.node, kind));
     descriptor->SetType(value_index++, input_node.type);
   }
   DCHECK(value_index == descriptor->GetSize());
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8