[turbofan] Deopt support for escape analysis

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 236 matching lines @@
   sequence()->MarkAsRepresentation(rep, unalloc.virtual_register());
 }
 
 
 void InstructionSelector::MarkAsRepresentation(MachineType rep, Node* node) {
   rep = RepresentationOf(rep);
   sequence()->MarkAsRepresentation(rep, GetVirtualRegister(node));
 }
 
 
-namespace {
-
-enum class FrameStateInputKind { kAny, kStackSlot };
-
-
-InstructionOperand OperandForDeopt(OperandGenerator* g, Node* input,
-                                   FrameStateInputKind kind) {
-  switch (input->opcode()) {
-    case IrOpcode::kInt32Constant:
-    case IrOpcode::kNumberConstant:
-    case IrOpcode::kFloat32Constant:
-    case IrOpcode::kFloat64Constant:
-    case IrOpcode::kHeapConstant:
-      return g->UseImmediate(input);
-    default:
-      switch (kind) {
-        case FrameStateInputKind::kStackSlot:
-          return g->UseUniqueSlot(input);
-        case FrameStateInputKind::kAny:
-          return g->UseAny(input);
-      }
-      UNREACHABLE();
-      return InstructionOperand();
-  }
-}
-
-
-void AddFrameStateInputs(Node* state, OperandGenerator* g,
-                         InstructionOperandVector* inputs,
-                         FrameStateDescriptor* descriptor,
-                         FrameStateInputKind kind, Zone* zone) {
-  DCHECK_EQ(IrOpcode::kFrameState, state->op()->opcode());
-
-  if (descriptor->outer_state()) {
-    AddFrameStateInputs(state->InputAt(kFrameStateOuterStateInput), g, inputs,
-                        descriptor->outer_state(), kind, zone);
-  }
-
-  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(zone);
-  types.reserve(descriptor->GetSize());
-
-  size_t value_index = 0;
-  inputs->push_back(OperandForDeopt(g, function, kind));
-  descriptor->SetType(value_index++, kMachAnyTagged);
-  for (StateValuesAccess::TypedNode input_node :
-       StateValuesAccess(parameters)) {
-    inputs->push_back(OperandForDeopt(g, input_node.node, kind));
-    descriptor->SetType(value_index++, input_node.type);
-  }
-  if (descriptor->HasContext()) {
-    inputs->push_back(OperandForDeopt(g, context, kind));
-    descriptor->SetType(value_index++, kMachAnyTagged);
-  }
-  for (StateValuesAccess::TypedNode input_node : StateValuesAccess(locals)) {
-    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(OperandForDeopt(g, input_node.node, kind));
-    descriptor->SetType(value_index++, input_node.type);
-  }
-  DCHECK(value_index == descriptor->GetSize());
-}
-
-}  // namespace
-
-
 // An internal helper class for generating the operands to calls.
 // TODO(bmeurer): Get rid of the CallBuffer business and make
 // InstructionSelector::VisitCall platform independent instead.
 struct CallBuffer {
   CallBuffer(Zone* zone, const CallDescriptor* descriptor,
              FrameStateDescriptor* frame_state)
       : descriptor(descriptor),
         frame_state_descriptor(frame_state),
         output_nodes(zone),
         outputs(zone),
@@ skipping 106 matching lines @@
       // The target is ignored, but we still need to pass a value here.
       buffer->instruction_args.push_back(g.UseImmediate(callee));
       break;
   }
   DCHECK_EQ(1u, buffer->instruction_args.size());
 
   // If the call needs a frame state, we insert the state information as
   // follows (n is the number of value inputs to the frame state):
   // arg 1               : deoptimization id.
   // arg 2 - arg (n + 1) : value inputs to the frame state.
+  size_t frame_state_entries = 0;
   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, &g, &buffer->instruction_args,
-                        buffer->frame_state_descriptor,
-                        FrameStateInputKind::kStackSlot, instruction_zone());
+
+    StateObjectCache cache(instruction_zone());
+
+    frame_state_entries =
+        1 +
+        buffer->frame_state_descriptor->AddInputs(
+            frame_state, &g, &cache, &buffer->instruction_args,
+            FrameStateInputKind::kStackSlot, instruction_zone());
+
+    DCHECK_EQ(1 + frame_state_entries, buffer->instruction_args.size());
   }
-  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.
   auto iter(call->inputs().begin());
   size_t pushed_count = 0;
   bool call_tail = (flags & kCallTail) != 0;
@@ skipping 15 matching lines @@
         buffer->pushed_nodes.resize(stack_index + 1, NULL);
       }
       DCHECK(!buffer->pushed_nodes[stack_index]);
       buffer->pushed_nodes[stack_index] = *iter;
       pushed_count++;
     } else {
       buffer->instruction_args.push_back(op);
     }
   }
   DCHECK_EQ(input_count, buffer->instruction_args.size() + pushed_count -
-                             buffer->frame_state_value_count());
+                             frame_state_entries);

[Jarin, 2015/12/02 12:24:34]

Hmm, does not the compiler complain that frame_state_entries is unused in
release mode?

[sigurds, 2015/12/02 16:35:13]

Done.

   if (call_tail && stack_param_delta != 0) {
     // For tail calls that change the size of their parameter list, move the
     // saved caller return address, parent frame pointer and parent constant
     // pool pointer to just above the parameters.
 
     // Return address
     LinkageLocation saved_return_location =
         LinkageLocation::ForSavedCallerReturnAddress();
     InstructionOperand return_address =
         g.UsePointerLocation(LinkageLocation::ConvertToTailCallerLocation(
@@ skipping 206 matching lines @@
       return MarkAsReference(node), VisitConstant(node);
     case IrOpcode::kNumberConstant: {
       double value = OpParameter<double>(node);
       if (!IsSmiDouble(value)) MarkAsReference(node);
       return VisitConstant(node);
     }
     case IrOpcode::kCall:
       return VisitCall(node);
     case IrOpcode::kFrameState:
     case IrOpcode::kStateValues:
+    case IrOpcode::kObjectState:
       return;
     case IrOpcode::kLoad: {
       LoadRepresentation rep = OpParameter<LoadRepresentation>(node);
       MarkAsRepresentation(rep, node);
       return VisitLoad(node);
     }
     case IrOpcode::kStore:
       return VisitStore(node);
     case IrOpcode::kWord32And:
       return MarkAsWord32(node), VisitWord32And(node);
@@ skipping 668 matching lines @@
     }
     Emit(kArchRet, 0, nullptr, ret_count, value_locations);
   }
 }
 
 
 void InstructionSelector::VisitDeoptimize(Node* value) {
   OperandGenerator g(this);
 
   FrameStateDescriptor* desc = GetFrameStateDescriptor(value);
-  size_t arg_count = desc->GetTotalSize() + 1;  // Include deopt id.
 
   InstructionOperandVector args(instruction_zone());
-  args.reserve(arg_count);
+  args.reserve(desc->GetTotalSize() + 1);  // Include deopt id.
 
   InstructionSequence::StateId state_id =
       sequence()->AddFrameStateDescriptor(desc);
   args.push_back(g.TempImmediate(state_id.ToInt()));
 
-  AddFrameStateInputs(value, &g, &args, desc, FrameStateInputKind::kAny,
-                      instruction_zone());
+  StateObjectCache cache(instruction_zone());
 
-  DCHECK_EQ(args.size(), arg_count);
+  desc->AddInputs(value, &g, &cache, &args, FrameStateInputKind::kAny,
+                  instruction_zone());
 
-  Emit(kArchDeoptimize, 0, nullptr, arg_count, &args.front(), 0, nullptr);
+  Emit(kArchDeoptimize, 0, nullptr, args.size(), &args.front(), 0, nullptr);
 }
 
 
 void InstructionSelector::VisitThrow(Node* value) {
   OperandGenerator g(this);
   Emit(kArchNop, g.NoOutput());  // TODO(titzer)
 }
 
 
 FrameStateDescriptor* InstructionSelector::GetFrameStateDescriptor(
@@ skipping 21 matching lines @@
   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);
 }
 
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8