[turbofan] Implement OSR for outer loops.

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 "src/compiler/instruction-selector-impl.h"
 #include "src/compiler/node-matchers.h"
 #include "src/compiler/node-properties-inl.h"
 #include "src/compiler/pipeline.h"
@@ skipping 446 matching lines @@
   // matching may cover more than one node at a time.
   for (BasicBlock::reverse_iterator i = block->rbegin(); i != block->rend();
        ++i) {
     Node* node = *i;
     // Skip nodes that are unused or already defined.
     if (!IsUsed(node) || IsDefined(node)) continue;
     // Generate code for this node "top down", but schedule the code "bottom
     // up".
     size_t current_node_end = instructions_.size();
     VisitNode(node);
+    // TODO(turbofan): only reverse if > 1 instruction emitted.

[Benedikt Meurer, 2015/01/11 11:50:22]

std::reverse handles that efficiently. No need to duplicate the work in our
code. Remove this TODO.

[titzer, 2015/01/12 10:43:53]

Hopefully so, TODO removed.

     std::reverse(instructions_.begin() + current_node_end, instructions_.end());
   }
 
   // We're done with the block.
   InstructionBlock* instruction_block =
       sequence()->InstructionBlockAt(block->GetRpoNumber());
   instruction_block->set_code_start(static_cast<int>(instructions_.size()));
   instruction_block->set_code_end(current_block_end);
 
   current_block_ = NULL;
@@ skipping 59 matching lines @@
     case IrOpcode::kIfFalse:
     case IrOpcode::kEffectPhi:
     case IrOpcode::kMerge:
     case IrOpcode::kTerminate:
       // No code needed for these graph artifacts.
       return kMachNone;
     case IrOpcode::kFinish:
       return kMachAnyTagged;
     case IrOpcode::kParameter:
       return linkage()->GetParameterType(OpParameter<int>(node));
+    case IrOpcode::kOsrValue:
+      return kMachAnyTagged;
     case IrOpcode::kPhi:
       return OpParameter<MachineType>(node);
     case IrOpcode::kProjection:
       // TODO(jarin) Really project from outputs.
       return kMachAnyTagged;
     case IrOpcode::kInt32Constant:
       return kMachInt32;
     case IrOpcode::kInt64Constant:
       return kMachInt64;
     case IrOpcode::kExternalConstant:
@@ skipping 118 matching lines @@
     case IrOpcode::kMerge:
       // No code needed for these graph artifacts.
       return;
     case IrOpcode::kFinish:
       return MarkAsReference(node), VisitFinish(node);
     case IrOpcode::kParameter: {
       MachineType type = linkage()->GetParameterType(OpParameter<int>(node));
       MarkAsRepresentation(type, node);
       return VisitParameter(node);
     }
+    case IrOpcode::kOsrValue:
+      return VisitOsrValue(node);

[Benedikt Meurer, 2015/01/11 11:50:22]

Missing MarkAsReference(node) here.

[titzer, 2015/01/12 10:43:53]

Done.

     case IrOpcode::kPhi: {
       MachineType type = OpParameter<MachineType>(node);
       MarkAsRepresentation(type, node);
       return VisitPhi(node);
     }
     case IrOpcode::kProjection:
       return VisitProjection(node);
     case IrOpcode::kInt32Constant:
     case IrOpcode::kInt64Constant:
     case IrOpcode::kExternalConstant:
@@ skipping 264 matching lines @@
 
 void InstructionSelector::VisitParameter(Node* node) {
   OperandGenerator g(this);
   int index = OpParameter<int>(node);
   Emit(kArchNop,
        g.DefineAsLocation(node, linkage()->GetParameterLocation(index),
                           linkage()->GetParameterType(index)));
 }
 
 
+void InstructionSelector::VisitOsrValue(Node* node) {
+  OperandGenerator g(this);
+  int index = OpParameter<int>(node);
+  Emit(kArchNop, g.DefineAsLocation(node, linkage()->GetOsrValueLocation(index),
+                                    kMachAnyTagged));
+}
+
+
 void InstructionSelector::VisitPhi(Node* node) {
   const int input_count = node->op()->ValueInputCount();
   PhiInstruction* phi = new (instruction_zone())
       PhiInstruction(instruction_zone(), GetVirtualRegister(node),
                      static_cast<size_t>(input_count));
   sequence()->InstructionBlockAt(current_block_->GetRpoNumber())->AddPhi(phi);
   for (int i = 0; i < input_count; ++i) {
     Node* const input = node->InputAt(i);
     MarkAsUsed(input);
     phi->Extend(instruction_zone(), GetVirtualRegister(input));
@@ skipping 171 matching lines @@
 MachineOperatorBuilder::Flags
 InstructionSelector::SupportedMachineOperatorFlags() {
   return MachineOperatorBuilder::Flag::kNoFlags;
 }
 
 #endif  // !V8_TURBOFAN_BACKEND
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8