[turbofan] decouple register allocation from schedule and graph

R=bmeurer@chromium.org, jarin@chromium.org

BUG=

Review URL: https://codereview.chromium.org/664683002

git-svn-id: https://v8.googlecode.com/svn/branches/bleeding_edge@24717 ce2b1a6d-e550-0410-aec6-3dcde31c8c00

src/compiler/instruction-selector.cc

@@ -853,8 +853,17 @@ void InstructionSelector::VisitParameter(Node* node) {
 
 void InstructionSelector::VisitPhi(Node* node) {
   // TODO(bmeurer): Emit a PhiInstruction here.
-  for (InputIter i = node->inputs().begin(); i != node->inputs().end(); ++i) {
-    MarkAsUsed(*i);
+  PhiInstruction* phi = new (instruction_zone())
+      PhiInstruction(instruction_zone(), sequence()->GetVirtualRegister(node));
+  sequence()->InstructionBlockAt(current_block_->GetRpoNumber())->AddPhi(phi);
+  Node::Inputs inputs = node->inputs();
+  size_t j = 0;
+  for (Node::Inputs::iterator iter(inputs.begin()); iter != inputs.end();
+       ++iter, ++j) {
+    MarkAsUsed(*iter);
+    // TODO(mstarzinger): Use a ValueInputIterator instead.
+    if (j >= current_block_->PredecessorCount()) continue;
+    phi->operands().push_back(sequence()->GetVirtualRegister(*iter));
   }
 }
 

src/compiler/instruction.cc

@@ -317,12 +317,75 @@ std::ostream& operator<<(std::ostream& os, const Constant& constant) {
 }
 
 
+static BasicBlock::RpoNumber GetRpo(BasicBlock* block) {
+  if (block == NULL) return BasicBlock::RpoNumber::Invalid();
+  return block->GetRpoNumber();
+}
+
+
+static BasicBlock::RpoNumber GetLoopEndRpo(const BasicBlock* block) {
+  if (!block->IsLoopHeader()) return BasicBlock::RpoNumber::Invalid();
+  return BasicBlock::RpoNumber::FromInt(block->loop_end());
+}
+
+
+InstructionBlock::InstructionBlock(Zone* zone, const BasicBlock* block)
+    : successors_(block->SuccessorCount(), BasicBlock::RpoNumber::Invalid(),
+                  zone),
+      predecessors_(block->PredecessorCount(), BasicBlock::RpoNumber::Invalid(),
+                    zone),
+      phis_(zone),
+      rpo_number_(block->GetRpoNumber()),
+      loop_header_(GetRpo(block->loop_header())),
+      loop_end_(GetLoopEndRpo(block)),
+      code_start_(-1),
+      code_end_(-1) {
+  // Map successors and precessors
+  size_t index = 0;
+  for (BasicBlock::Successors::const_iterator it = block->successors_begin();
+       it != block->successors_end(); ++it, ++index) {
+    successors_[index] = (*it)->GetRpoNumber();
+  }
+  index = 0;
+  for (BasicBlock::Predecessors::const_iterator
+           it = block->predecessors_begin();
+       it != block->predecessors_end(); ++it, ++index) {
+    predecessors_[index] = (*it)->GetRpoNumber();
+  }
+}
+
+
+size_t InstructionBlock::PredecessorIndexOf(
+    BasicBlock::RpoNumber rpo_number) const {
+  size_t j = 0;
+  for (InstructionBlock::Predecessors::const_iterator i = predecessors_.begin();
+       i != predecessors_.end(); ++i, ++j) {
+    if (*i == rpo_number) break;
+  }
+  return j;
+}
+
+
+static void InitializeInstructionBlocks(Zone* zone, const Schedule* schedule,
+                                        InstructionBlocks* blocks) {
+  DCHECK(blocks->size() == schedule->rpo_order()->size());
+  size_t rpo_number = 0;
+  for (BasicBlockVector::const_iterator it = schedule->rpo_order()->begin();
+       it != schedule->rpo_order()->end(); ++it, ++rpo_number) {
+    DCHECK_EQ(NULL, (*blocks)[rpo_number]);
+    DCHECK((*it)->GetRpoNumber().ToSize() == rpo_number);
+    (*blocks)[rpo_number] = new (zone) InstructionBlock(zone, *it);
+  }
+}
+
+
 InstructionSequence::InstructionSequence(Linkage* linkage, Graph* graph,
                                          Schedule* schedule)
-    : zone_(schedule->zone()),
+    : zone_(schedule->zone()),  // TODO(dcarney): new zone.
       node_count_(graph->NodeCount()),
       node_map_(zone()->NewArray<int>(node_count_)),
-      block_data_(static_cast<int>(schedule->BasicBlockCount()), zone()),
+      instruction_blocks_(static_cast<int>(schedule->rpo_order()->size()), NULL,
+                          zone()),
       linkage_(linkage),
       schedule_(schedule),
       constants_(ConstantMap::key_compare(),
@@ -337,6 +400,7 @@ InstructionSequence::InstructionSequence(Linkage* linkage, Graph* graph,
   for (int i = 0; i < node_count_; ++i) {
     node_map_[i] = -1;
   }
+  InitializeInstructionBlocks(zone(), schedule, &instruction_blocks_);
 }
 
 
@@ -408,6 +472,20 @@ BasicBlock* InstructionSequence::GetBasicBlock(int instruction_index) {
 }
 
 
+const InstructionBlock* InstructionSequence::GetInstructionBlock(
+    int instruction_index) const {
+  // TODO(turbofan): Optimize this.
+  for (;;) {
+    DCHECK_LE(0, instruction_index);
+    Instruction* instruction = InstructionAt(instruction_index--);
+    if (instruction->IsBlockStart()) {
+      return instruction_blocks_
+          [BlockStartInstruction::cast(instruction)->rpo_number().ToSize()];
+    }
+  }
+}
+
+
 bool InstructionSequence::IsReference(int virtual_register) const {
   return references_.find(virtual_register) != references_.end();
 }

src/compiler/instruction.h

@@ -753,6 +753,81 @@ class FrameStateDescriptor : public ZoneObject {
 
 std::ostream& operator<<(std::ostream& os, const Constant& constant);
 
+
+// TODO(dcarney): this is a temporary hack.  turn into an actual instruction.
+class PhiInstruction : public ZoneObject {
+ public:
+  PhiInstruction(Zone* zone, int virtual_register)
+      : virtual_register_(virtual_register), operands_(zone) {}
+
+  int virtual_register() const { return virtual_register_; }
+  const IntVector& operands() const { return operands_; }
+  IntVector& operands() { return operands_; }
+
+ private:
+  const int virtual_register_;
+  IntVector operands_;
+};
+
+
+// Analogue of BasicBlock for Instructions instead of Nodes.
+class InstructionBlock : public ZoneObject {
+ public:
+  explicit InstructionBlock(Zone* zone, const BasicBlock* block);
+
+  // Instruction indexes (used by the register allocator).
+  int first_instruction_index() const {
+    DCHECK(code_start_ >= 0);
+    DCHECK(code_end_ > 0);
+    DCHECK(code_end_ >= code_start_);
+    return code_start_;
+  }
+  int last_instruction_index() const {
+    DCHECK(code_start_ >= 0);
+    DCHECK(code_end_ > 0);
+    DCHECK(code_end_ >= code_start_);
+    return code_end_ - 1;
+  }
+
+  int32_t code_start() const { return code_start_; }
+  void set_code_start(int32_t start) { code_start_ = start; }
+
+  int32_t code_end() const { return code_end_; }
+  void set_code_end(int32_t end) { code_end_ = end; }
+
+  BasicBlock::RpoNumber rpo_number() const { return rpo_number_; }
+  BasicBlock::RpoNumber loop_header() const { return loop_header_; }
+  BasicBlock::RpoNumber loop_end() const {
+    DCHECK(IsLoopHeader());
+    return loop_end_;
+  }
+  inline bool IsLoopHeader() const { return loop_end_.IsValid(); }
+
+  typedef ZoneVector<BasicBlock::RpoNumber> Predecessors;
+  const Predecessors& predecessors() const { return predecessors_; }
+  size_t PredecessorCount() const { return predecessors_.size(); }
+  size_t PredecessorIndexOf(BasicBlock::RpoNumber rpo_number) const;
+
+  typedef ZoneVector<BasicBlock::RpoNumber> Successors;
+  const Successors& successors() const { return successors_; }
+  size_t SuccessorCount() const { return successors_.size(); }
+
+  typedef ZoneVector<PhiInstruction*> PhiInstructions;
+  const PhiInstructions& phis() const { return phis_; }
+  void AddPhi(PhiInstruction* phi) { phis_.push_back(phi); }
+
+ private:
+  Successors successors_;
+  Predecessors predecessors_;
+  PhiInstructions phis_;
+  // TODO(dcarney): probably dont't need this.
+  BasicBlock::RpoNumber rpo_number_;
+  BasicBlock::RpoNumber loop_header_;
+  BasicBlock::RpoNumber loop_end_;
+  int32_t code_start_;  // start index of arch-specific code.
+  int32_t code_end_;    // end index of arch-specific code.
+};
+
 typedef ZoneDeque<Constant> ConstantDeque;
 typedef std::map<int, Constant, std::less<int>,
                  zone_allocator<std::pair<int, Constant> > > ConstantMap;
@@ -760,6 +835,7 @@ typedef std::map<int, Constant, std::less<int>,
 typedef ZoneDeque<Instruction*> InstructionDeque;
 typedef ZoneDeque<PointerMap*> PointerMapDeque;
 typedef ZoneVector<FrameStateDescriptor*> DeoptimizationVector;
+typedef ZoneVector<InstructionBlock*> InstructionBlocks;
 
 // Represents architecture-specific generated code before, during, and after
 // register allocation.
@@ -774,18 +850,32 @@ class InstructionSequence FINAL {
   int node_count() const { return node_count_; }
 
   int BasicBlockCount() const {
-    return static_cast<int>(schedule_->rpo_order()->size());
+    return static_cast<int>(instruction_blocks_.size());
   }
 
   BasicBlock* BlockAt(int rpo_number) const {
     return (*schedule_->rpo_order())[rpo_number];
   }
 
-  BasicBlock* GetContainingLoop(BasicBlock* block) {
-    return block->loop_header();
+  InstructionBlock* InstructionBlockAt(BasicBlock::RpoNumber rpo_number) {
+    return GetBlock(rpo_number);
+  }
+
+  const InstructionBlock* InstructionBlockAt(
+      BasicBlock::RpoNumber rpo_number) const {
+    return GetBlock(rpo_number);
+  }
+
+  // TODO(dcarney): move to register allocator.
+  const InstructionBlock* GetContainingLoop(
+      const InstructionBlock* block) const {
+    BasicBlock::RpoNumber index = block->loop_header();
+    if (!index.IsValid()) return NULL;
+    return instruction_blocks_[index.ToInt()];
   }
 
   BasicBlock* GetBasicBlock(int instruction_index);
+  const InstructionBlock* GetInstructionBlock(int instruction_index) const;
 
   int GetVirtualRegister(const Node* node);
   // TODO(dcarney): find a way to remove this.
@@ -828,26 +918,32 @@ class InstructionSequence FINAL {
   void StartBlock(BasicBlock* block);
   void EndBlock(BasicBlock* block);
   void set_code_start(BasicBlock* block, int start) {
-    return GetBlockData(block->GetRpoNumber()).set_code_start(start);
+    return GetBlock(block->GetRpoNumber())->set_code_start(start);
   }
   void set_code_end(BasicBlock* block, int end) {
-    return GetBlockData(block->GetRpoNumber()).set_code_end(end);
+    return GetBlock(block->GetRpoNumber())->set_code_end(end);
   }
   // TODO(dcarney): use RpoNumber for all of the below.
   int code_start(BasicBlock::RpoNumber rpo_number) const {
-    return GetBlockData(rpo_number).code_start();
+    return GetBlock(rpo_number)->code_start();
   }
   int code_start(BasicBlock* block) const {
-    return GetBlockData(block->GetRpoNumber()).code_start();
+    return GetBlock(block->GetRpoNumber())->code_start();
   }
   int code_end(BasicBlock* block) const {
-    return GetBlockData(block->GetRpoNumber()).code_end();
+    return GetBlock(block->GetRpoNumber())->code_end();
   }
   int first_instruction_index(BasicBlock* block) const {
-    return GetBlockData(block->GetRpoNumber()).first_instruction_index();
+    return GetBlock(block->GetRpoNumber())->first_instruction_index();
   }
   int last_instruction_index(BasicBlock* block) const {
-    return GetBlockData(block->GetRpoNumber()).last_instruction_index();
+    return GetBlock(block->GetRpoNumber())->last_instruction_index();
+  }
+  int first_instruction_index(InstructionBlock* block) const {
+    return GetBlock(block->rpo_number())->first_instruction_index();
+  }
+  int last_instruction_index(InstructionBlock* block) const {
+    return GetBlock(block->rpo_number())->last_instruction_index();
   }
 
   int AddConstant(Node* node, Constant constant) {
@@ -892,51 +988,19 @@ class InstructionSequence FINAL {
   int GetFrameStateDescriptorCount();
 
  private:
-  class BlockData {
-   public:
-    BlockData() : code_start_(-1), code_end_(-1) {}
-    // Instruction indexes (used by the register allocator).
-    int first_instruction_index() const {
-      DCHECK(code_start_ >= 0);
-      DCHECK(code_end_ > 0);
-      DCHECK(code_end_ >= code_start_);
-      return code_start_;
-    }
-    int last_instruction_index() const {
-      DCHECK(code_start_ >= 0);
-      DCHECK(code_end_ > 0);
-      DCHECK(code_end_ >= code_start_);
-      return code_end_ - 1;
-    }
-
-    int32_t code_start() const { return code_start_; }
-    void set_code_start(int32_t start) { code_start_ = start; }
-
-    int32_t code_end() const { return code_end_; }
-    void set_code_end(int32_t end) { code_end_ = end; }
-
-   private:
-    int32_t code_start_;  // start index of arch-specific code.
-    int32_t code_end_;    // end index of arch-specific code.
-  };
-
-  const BlockData& GetBlockData(BasicBlock::RpoNumber rpo_number) const {
-    return block_data_[rpo_number.ToSize()];
-  }
-  BlockData& GetBlockData(BasicBlock::RpoNumber rpo_number) {
-    return block_data_[rpo_number.ToSize()];
+  InstructionBlock* GetBlock(BasicBlock::RpoNumber rpo_number) const {
+    return instruction_blocks_[rpo_number.ToSize()];
   }
 
   friend std::ostream& operator<<(std::ostream& os,
                                   const InstructionSequence& code);
 
   typedef std::set<int, std::less<int>, ZoneIntAllocator> VirtualRegisterSet;
-  typedef ZoneVector<BlockData> BlockDataVector;
 
   Zone* zone_;
   int node_count_;
   int* node_map_;
-  BlockDataVector block_data_;
+  InstructionBlocks instruction_blocks_;
   Linkage* linkage_;
   Schedule* schedule_;
   ConstantMap constants_;

src/compiler/register-allocator.h

@@ -7,8 +7,6 @@
 
 #include "src/allocation.h"
 #include "src/compiler/instruction.h"
-#include "src/compiler/node.h"
-#include "src/compiler/schedule.h"
 #include "src/macro-assembler.h"
 #include "src/zone.h"
 
@@ -378,21 +376,22 @@ class RegisterAllocator BASE_EMBEDDED {
   void ResolveControlFlow();
   void PopulatePointerMaps();  // TODO(titzer): rename to PopulateReferenceMaps.
   void AllocateRegisters();
-  bool CanEagerlyResolveControlFlow(BasicBlock* block) const;
+  bool CanEagerlyResolveControlFlow(const InstructionBlock* block) const;
   inline bool SafePointsAreInOrder() const;
 
   // Liveness analysis support.
   void InitializeLivenessAnalysis();
-  BitVector* ComputeLiveOut(BasicBlock* block);
-  void AddInitialIntervals(BasicBlock* block, BitVector* live_out);
+  BitVector* ComputeLiveOut(const InstructionBlock* block);
+  void AddInitialIntervals(const InstructionBlock* block, BitVector* live_out);
   bool IsOutputRegisterOf(Instruction* instr, int index);
   bool IsOutputDoubleRegisterOf(Instruction* instr, int index);
-  void ProcessInstructions(BasicBlock* block, BitVector* live);
-  void MeetRegisterConstraints(BasicBlock* block);
+  void ProcessInstructions(const InstructionBlock* block, BitVector* live);
+  void MeetRegisterConstraints(const InstructionBlock* block);
   void MeetConstraintsBetween(Instruction* first, Instruction* second,
                               int gap_index);
-  void MeetRegisterConstraintsForLastInstructionInBlock(BasicBlock* block);
-  void ResolvePhis(BasicBlock* block);
+  void MeetRegisterConstraintsForLastInstructionInBlock(
+      const InstructionBlock* block);
+  void ResolvePhis(const InstructionBlock* block);
 
   // Helper methods for building intervals.
   InstructionOperand* AllocateFixed(UnallocatedOperand* operand, int pos,
@@ -466,8 +465,8 @@ class RegisterAllocator BASE_EMBEDDED {
   bool IsBlockBoundary(LifetimePosition pos);
 
   // Helper methods for resolving control flow.
-  void ResolveControlFlow(LiveRange* range, BasicBlock* block,
-                          BasicBlock* pred);
+  void ResolveControlFlow(LiveRange* range, const InstructionBlock* block,
+                          const InstructionBlock* pred);
 
   inline void SetLiveRangeAssignedRegister(LiveRange* range, int reg);
 
@@ -476,7 +475,7 @@ class RegisterAllocator BASE_EMBEDDED {
   ParallelMove* GetConnectingParallelMove(LifetimePosition pos);
 
   // Return the block which contains give lifetime position.
-  BasicBlock* GetBlock(LifetimePosition pos);
+  const InstructionBlock* GetInstructionBlock(LifetimePosition pos);
 
   // Helper methods for the fixed registers.
   int RegisterCount() const;
@@ -485,7 +484,7 @@ class RegisterAllocator BASE_EMBEDDED {
   LiveRange* FixedLiveRangeFor(int index);
   LiveRange* FixedDoubleLiveRangeFor(int index);
   LiveRange* LiveRangeFor(int index);
-  GapInstruction* GetLastGap(BasicBlock* block);
+  GapInstruction* GetLastGap(const InstructionBlock* block);
 
   const char* RegisterName(int allocation_index);
 

src/compiler/schedule.cc

@@ -35,12 +35,6 @@ bool BasicBlock::LoopContains(BasicBlock* block) const {
 }
 
 
-BasicBlock* BasicBlock::ContainingLoop() {
-  if (IsLoopHeader()) return this;
-  return loop_header();
-}
-
-
 void BasicBlock::AddSuccessor(BasicBlock* successor) {
   successors_.push_back(successor);
 }
@@ -88,16 +82,6 @@ void BasicBlock::set_loop_header(BasicBlock* loop_header) {
 }
 
 
-size_t BasicBlock::PredecessorIndexOf(BasicBlock* predecessor) {
-  size_t j = 0;
-  for (BasicBlock::Predecessors::iterator i = predecessors_.begin();
-       i != predecessors_.end(); ++i, ++j) {
-    if (*i == predecessor) break;
-  }
-  return j;
-}
-
-
 std::ostream& operator<<(std::ostream& os, const BasicBlock::Control& c) {
   switch (c) {
     case BasicBlock::kNone:

src/compiler/schedule.h

@@ -50,22 +50,33 @@ class BasicBlock FINAL : public ZoneObject {
     size_t index_;
   };
 
+  static const int kInvalidRpoNumber = -1;
   class RpoNumber FINAL {
    public:
-    int ToInt() const { return static_cast<int>(index_); }
-    size_t ToSize() const { return index_; }
-    static RpoNumber FromInt(int index) {
-      return RpoNumber(static_cast<size_t>(index));
+    int ToInt() const {
+      DCHECK(IsValid());
+      return index_;
+    }
+    size_t ToSize() const {
+      DCHECK(IsValid());
+      return static_cast<size_t>(index_);
     }
-    static RpoNumber Invalid() { return RpoNumber(static_cast<size_t>(-1)); }
+    bool IsValid() const { return index_ != kInvalidRpoNumber; }
+    static RpoNumber FromInt(int index) { return RpoNumber(index); }
+    static RpoNumber Invalid() { return RpoNumber(kInvalidRpoNumber); }
 
     bool IsNext(const RpoNumber other) const {
+      DCHECK(IsValid());
       return other.index_ == this->index_ + 1;
     }
 
+    bool operator==(RpoNumber other) const {
+      return this->index_ == other.index_;
+    }
+
    private:
-    explicit RpoNumber(size_t index) : index_(index) {}
-    size_t index_;
+    explicit RpoNumber(int32_t index) : index_(index) {}
+    int32_t index_;
   };
 
   BasicBlock(Zone* zone, Id id);
@@ -76,14 +87,25 @@ class BasicBlock FINAL : public ZoneObject {
   typedef ZoneVector<BasicBlock*> Predecessors;
   Predecessors::iterator predecessors_begin() { return predecessors_.begin(); }
   Predecessors::iterator predecessors_end() { return predecessors_.end(); }
+  Predecessors::const_iterator predecessors_begin() const {
+    return predecessors_.begin();
+  }
+  Predecessors::const_iterator predecessors_end() const {
+    return predecessors_.end();
+  }
   size_t PredecessorCount() const { return predecessors_.size(); }
   BasicBlock* PredecessorAt(size_t index) { return predecessors_[index]; }
-  size_t PredecessorIndexOf(BasicBlock* predecessor);
   void AddPredecessor(BasicBlock* predecessor);
 
   typedef ZoneVector<BasicBlock*> Successors;
   Successors::iterator successors_begin() { return successors_.begin(); }
   Successors::iterator successors_end() { return successors_.end(); }
+  Successors::const_iterator successors_begin() const {
+    return successors_.begin();
+  }
+  Successors::const_iterator successors_end() const {
+    return successors_.end();
+  }
   size_t SuccessorCount() const { return successors_.size(); }
   BasicBlock* SuccessorAt(size_t index) { return successors_[index]; }
   void AddSuccessor(BasicBlock* successor);
@@ -137,7 +159,6 @@ class BasicBlock FINAL : public ZoneObject {
   // Loop membership helpers.
   inline bool IsLoopHeader() const { return loop_end_ >= 0; }
   bool LoopContains(BasicBlock* block) const;
-  BasicBlock* ContainingLoop();
 
  private:
   int32_t rpo_number_;       // special RPO number of the block.