[turbofan] Implement OSR for outer loops.

src/compiler/instruction-selector.cc

Index: src/compiler/instruction-selector.cc
diff --git a/src/compiler/instruction-selector.cc b/src/compiler/instruction-selector.cc
index f987248bead41d33f3acf4146703ed11daa3ebaf..6679956f9627fa80b162cd010b50a19bf4ca2149 100644
--- a/src/compiler/instruction-selector.cc
+++ b/src/compiler/instruction-selector.cc
@@ -464,6 +464,7 @@ void InstructionSelector::VisitBlock(BasicBlock* block) {
     // 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());
   }
 
@@ -543,6 +544,8 @@ MachineType InstructionSelector::GetMachineType(Node* node) {
       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:
@@ -681,6 +684,8 @@ void InstructionSelector::VisitNode(Node* 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);
@@ -965,6 +970,14 @@ void InstructionSelector::VisitParameter(Node* node) {
 }
 
 
+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())