Revert of [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 12 matching lines @@
     InstructionSequence* sequence, Schedule* schedule,
     SourcePositionTable* source_positions,
     SourcePositionMode source_position_mode, Features features)
     : zone_(zone),
       linkage_(linkage),
       sequence_(sequence),
       source_positions_(source_positions),
       source_position_mode_(source_position_mode),
       features_(features),
       schedule_(schedule),
-      current_block_(nullptr),
+      current_block_(NULL),
       instructions_(zone),
       defined_(node_count, false, zone),
       used_(node_count, false, zone),
       virtual_registers_(node_count,
-                         InstructionOperand::kInvalidVirtualRegister, zone),
-      scheduler_(nullptr) {
+                         InstructionOperand::kInvalidVirtualRegister, zone) {
   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 &&
-      InstructionScheduler::SchedulerSupported()) {
-    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);
-    StartBlock(RpoNumber::FromInt(block->rpo_number()));
+    sequence()->StartBlock(RpoNumber::FromInt(block->rpo_number()));
     while (start-- > end) {
-      AddInstruction(instructions_[start]);
+      sequence()->AddInstruction(instructions_[start]);
     }
-    EndBlock(RpoNumber::FromInt(block->rpo_number()));
+    sequence()->EndBlock(RpoNumber::FromInt(block->rpo_number()));
   }
 }
 
-
-void InstructionSelector::StartBlock(RpoNumber rpo) {
-  if (FLAG_turbo_instruction_scheduling &&
-      InstructionScheduler::SchedulerSupported()) {
-    DCHECK(scheduler_ != nullptr);
-    scheduler_->StartBlock(rpo);
-  } else {
-    sequence()->StartBlock(rpo);
-  }
-}
-
-
-void InstructionSelector::EndBlock(RpoNumber rpo) {
-  if (FLAG_turbo_instruction_scheduling &&
-      InstructionScheduler::SchedulerSupported()) {
-    DCHECK(scheduler_ != nullptr);
-    scheduler_->EndBlock(rpo);
-  } else {
-    sequence()->EndBlock(rpo);
-  }
-}
-
-
-void InstructionSelector::AddInstruction(Instruction* instr) {
-  if (FLAG_turbo_instruction_scheduling &&
-      InstructionScheduler::SchedulerSupported()) {
-    DCHECK(scheduler_ != nullptr);
-    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 1348 matching lines @@
     case DeoptimizeKind::kSoft:
       opcode |= MiscField::encode(Deoptimizer::SOFT);
       break;
   }
   Emit(opcode, 0, nullptr, arg_count, &args.front(), 0, nullptr);
 }
 
 
 void InstructionSelector::VisitThrow(Node* value) {
   OperandGenerator g(this);
-  Emit(kArchThrowTerminator, g.NoOutput());  // TODO(titzer)
+  Emit(kArchNop, g.NoOutput());  // TODO(titzer)
 }
 
 
 FrameStateDescriptor* InstructionSelector::GetFrameStateDescriptor(
     Node* state) {
   DCHECK(state->opcode() == IrOpcode::kFrameState);
   DCHECK_EQ(kFrameStateInputCount, state->InputCount());
   FrameStateInfo state_info = OpParameter<FrameStateInfo>(state);
 
   int parameters = static_cast<int>(
@@ skipping 15 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