[WIP][turbofan] Instruction scheduler for Turbofan.

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 16 matching lines @@
       sequence_(sequence),
       source_positions_(source_positions),
       source_position_mode_(source_position_mode),
       features_(features),
       schedule_(schedule),
       current_block_(NULL),
       instructions_(zone),
       defined_(node_count, false, zone),
       used_(node_count, false, zone),
       virtual_registers_(node_count,
-                         InstructionOperand::kInvalidVirtualRegister, zone) {
+                         InstructionOperand::kInvalidVirtualRegister, zone),
+      scheduler_(nullptr) {
   instructions_.reserve(node_count);
 }
 
 
 void InstructionSelector::SelectInstructions() {
   // Mark the inputs of all phis in loop headers as used.
   BasicBlockVector* blocks = schedule()->rpo_order();
   for (auto const block : *blocks) {
     if (!block->IsLoopHeader()) continue;
     DCHECK_LE(2u, block->PredecessorCount());
     for (Node* const phi : *block) {
       if (phi->opcode() != IrOpcode::kPhi) continue;
 
       // Mark all inputs as used.
       for (Node* const input : phi->inputs()) {
         MarkAsUsed(input);
       }
     }
   }
 
   // Visit each basic block in post order.
   for (auto i = blocks->rbegin(); i != blocks->rend(); ++i) {
     VisitBlock(*i);
   }
 
   // Schedule the selected instructions.
+  if (FLAG_turbo_instruction_scheduling) {
+    scheduler_ = new (zone()) InstructionScheduler(zone(), sequence());
+  }
+
   for (auto const block : *blocks) {
     InstructionBlock* instruction_block =
         sequence()->InstructionBlockAt(RpoNumber::FromInt(block->rpo_number()));
     size_t end = instruction_block->code_end();
     size_t start = instruction_block->code_start();
     DCHECK_LE(end, start);
-    sequence()->StartBlock(RpoNumber::FromInt(block->rpo_number()));
+    StartBlock(RpoNumber::FromInt(block->rpo_number()));
     while (start-- > end) {
-      sequence()->AddInstruction(instructions_[start]);
+      AddInstruction(instructions_[start]);
     }
-    sequence()->EndBlock(RpoNumber::FromInt(block->rpo_number()));
+    EndBlock(RpoNumber::FromInt(block->rpo_number()));
   }
 }
 
+
+void InstructionSelector::StartBlock(RpoNumber rpo) {
+  if (FLAG_turbo_instruction_scheduling) {
+    scheduler_->StartBlock(rpo);
+  } else {
+    sequence()->StartBlock(rpo);
+  }
+}
+
+
+void InstructionSelector::EndBlock(RpoNumber rpo) {
+  if (FLAG_turbo_instruction_scheduling) {
+    scheduler_->EndBlock(rpo);
+  } else {
+    sequence()->EndBlock(rpo);
+  }
+}
+
+
+void InstructionSelector::AddInstruction(Instruction* instr) {
+  if (FLAG_turbo_instruction_scheduling) {
+    scheduler_->AddInstruction(instr);
+  } else {
+    sequence()->AddInstruction(instr);
+  }
+}
+
 
 Instruction* InstructionSelector::Emit(InstructionCode opcode,
                                        InstructionOperand output,
                                        size_t temp_count,
                                        InstructionOperand* temps) {
   size_t output_count = output.IsInvalid() ? 0 : 1;
   return Emit(opcode, output_count, &output, 0, NULL, temp_count, temps);
 }
 
 
@@ skipping 1056 matching lines @@
   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 compiler
 }  // namespace internal
 }  // namespace v8