[Isolates] Merge r 6300:6500 from bleeding_edge to isolates.

src/lithium.cc

Index: src/lithium.cc
===================================================================
--- src/lithium.cc	(revision 6955)
+++ src/lithium.cc	(working copy)
@@ -31,157 +31,77 @@
 namespace internal {
 
 
-class LGapNode: public ZoneObject {
- public:
-  explicit LGapNode(LOperand* operand)
-      : operand_(operand), resolved_(false), visited_id_(-1) { }
-
-  LOperand* operand() const { return operand_; }
-  bool IsResolved() const { return !IsAssigned() || resolved_; }
-  void MarkResolved() {
-    ASSERT(!IsResolved());
-    resolved_ = true;
-  }
-  int visited_id() const { return visited_id_; }
-  void set_visited_id(int id) {
-    ASSERT(id > visited_id_);
-    visited_id_ = id;
-  }
-
-  bool IsAssigned() const { return assigned_from_.is_set(); }
-  LGapNode* assigned_from() const { return assigned_from_.get(); }
-  void set_assigned_from(LGapNode* n) { assigned_from_.set(n); }
-
- private:
-  LOperand* operand_;
-  SetOncePointer<LGapNode> assigned_from_;
-  bool resolved_;
-  int visited_id_;
-};
-
-
-LGapResolver::LGapResolver()
-    : nodes_(32),
-      identified_cycles_(4),
-      result_(16),
-      next_visited_id_(0) {
-}
-
-
-const ZoneList<LMoveOperands>* LGapResolver::Resolve(
-    const ZoneList<LMoveOperands>* moves,
-    LOperand* marker_operand) {
-  nodes_.Rewind(0);
-  identified_cycles_.Rewind(0);
-  result_.Rewind(0);
-  next_visited_id_ = 0;
-
-  for (int i = 0; i < moves->length(); ++i) {
-    LMoveOperands move = moves->at(i);
-    if (!move.IsRedundant()) RegisterMove(move);
-  }
-
-  for (int i = 0; i < identified_cycles_.length(); ++i) {
-    ResolveCycle(identified_cycles_[i], marker_operand);
-  }
-
-  int unresolved_nodes;
-  do {
-    unresolved_nodes = 0;
-    for (int j = 0; j < nodes_.length(); j++) {
-      LGapNode* node = nodes_[j];
-      if (!node->IsResolved() && node->assigned_from()->IsResolved()) {
-        AddResultMove(node->assigned_from(), node);
-        node->MarkResolved();
+void LOperand::PrintTo(StringStream* stream) {
+  LUnallocated* unalloc = NULL;
+  switch (kind()) {
+    case INVALID:
+      break;
+    case UNALLOCATED:
+      unalloc = LUnallocated::cast(this);
+      stream->Add("v%d", unalloc->virtual_register());
+      switch (unalloc->policy()) {
+        case LUnallocated::NONE:
+          break;
+        case LUnallocated::FIXED_REGISTER: {
+          const char* register_name =
+              Register::AllocationIndexToString(unalloc->fixed_index());
+          stream->Add("(=%s)", register_name);
+          break;
+        }
+        case LUnallocated::FIXED_DOUBLE_REGISTER: {
+          const char* double_register_name =
+              DoubleRegister::AllocationIndexToString(unalloc->fixed_index());
+          stream->Add("(=%s)", double_register_name);
+          break;
+        }
+        case LUnallocated::FIXED_SLOT:
+          stream->Add("(=%dS)", unalloc->fixed_index());
+          break;
+        case LUnallocated::MUST_HAVE_REGISTER:
+          stream->Add("(R)");
+          break;
+        case LUnallocated::WRITABLE_REGISTER:
+          stream->Add("(WR)");
+          break;
+        case LUnallocated::SAME_AS_FIRST_INPUT:
+          stream->Add("(1)");
+          break;
+        case LUnallocated::ANY:
+          stream->Add("(-)");
+          break;
+        case LUnallocated::IGNORE:
+          stream->Add("(0)");
+          break;
       }
-      if (!node->IsResolved()) ++unresolved_nodes;
-    }
-  } while (unresolved_nodes > 0);
-  return &result_;
-}
-
-
-void LGapResolver::AddResultMove(LGapNode* from, LGapNode* to) {
-  AddResultMove(from->operand(), to->operand());
-}
-
-
-void LGapResolver::AddResultMove(LOperand* from, LOperand* to) {
-  result_.Add(LMoveOperands(from, to));
-}
-
-
-void LGapResolver::ResolveCycle(LGapNode* start, LOperand* marker_operand) {
-  ZoneList<LOperand*> cycle_operands(8);
-  cycle_operands.Add(marker_operand);
-  LGapNode* cur = start;
-  do {
-    cur->MarkResolved();
-    cycle_operands.Add(cur->operand());
-    cur = cur->assigned_from();
-  } while (cur != start);
-  cycle_operands.Add(marker_operand);
-
-  for (int i = cycle_operands.length() - 1; i > 0; --i) {
-    LOperand* from = cycle_operands[i];
-    LOperand* to = cycle_operands[i - 1];
-    AddResultMove(from, to);
+      break;
+    case CONSTANT_OPERAND:
+      stream->Add("[constant:%d]", index());
+      break;
+    case STACK_SLOT:
+      stream->Add("[stack:%d]", index());
+      break;
+    case DOUBLE_STACK_SLOT:
+      stream->Add("[double_stack:%d]", index());
+      break;
+    case REGISTER:
+      stream->Add("[%s|R]", Register::AllocationIndexToString(index()));
+      break;
+    case DOUBLE_REGISTER:
+      stream->Add("[%s|R]", DoubleRegister::AllocationIndexToString(index()));
+      break;
+    case ARGUMENT:
+      stream->Add("[arg:%d]", index());
+      break;
   }
 }
 
 
-bool LGapResolver::CanReach(LGapNode* a, LGapNode* b, int visited_id) {
-  ASSERT(a != b);
-  LGapNode* cur = a;
-  while (cur != b && cur->visited_id() != visited_id && cur->IsAssigned()) {
-    cur->set_visited_id(visited_id);
-    cur = cur->assigned_from();
-  }
-
-  return cur == b;
+int LOperand::VirtualRegister() {
+  LUnallocated* unalloc = LUnallocated::cast(this);
+  return unalloc->virtual_register();
 }
 
 
-bool LGapResolver::CanReach(LGapNode* a, LGapNode* b) {
-  ASSERT(a != b);
-  return CanReach(a, b, next_visited_id_++);
-}
-
-
-void LGapResolver::RegisterMove(LMoveOperands move) {
-  if (move.from()->IsConstantOperand()) {
-    // Constant moves should be last in the machine code. Therefore add them
-    // first to the result set.
-    AddResultMove(move.from(), move.to());
-  } else {
-    LGapNode* from = LookupNode(move.from());
-    LGapNode* to = LookupNode(move.to());
-    if (to->IsAssigned() && to->assigned_from() == from) {
-      move.Eliminate();
-      return;
-    }
-    ASSERT(!to->IsAssigned());
-    if (CanReach(from, to)) {
-      // This introduces a cycle. Save.
-      identified_cycles_.Add(from);
-    }
-    to->set_assigned_from(from);
-  }
-}
-
-
-LGapNode* LGapResolver::LookupNode(LOperand* operand) {
-  for (int i = 0; i < nodes_.length(); ++i) {
-    if (nodes_[i]->operand()->Equals(operand)) return nodes_[i];
-  }
-
-  // No node found => create a new one.
-  LGapNode* result = new LGapNode(operand);
-  nodes_.Add(result);
-  return result;
-}
-
-
 bool LParallelMove::IsRedundant() const {
   for (int i = 0; i < move_operands_.length(); ++i) {
     if (!move_operands_[i].IsRedundant()) return false;
@@ -191,18 +111,21 @@
 
 
 void LParallelMove::PrintDataTo(StringStream* stream) const {
-  for (int i = move_operands_.length() - 1; i >= 0; --i) {
+  bool first = true;
+  for (int i = 0; i < move_operands_.length(); ++i) {
     if (!move_operands_[i].IsEliminated()) {
-      LOperand* from = move_operands_[i].from();
-      LOperand* to = move_operands_[i].to();
-      if (from->Equals(to)) {
-        to->PrintTo(stream);
+      LOperand* source = move_operands_[i].source();
+      LOperand* destination = move_operands_[i].destination();
+      if (!first) stream->Add(" ");
+      first = false;
+      if (source->Equals(destination)) {
+        destination->PrintTo(stream);
       } else {
-        to->PrintTo(stream);
+        destination->PrintTo(stream);
         stream->Add(" = ");
-        from->PrintTo(stream);
+        source->PrintTo(stream);
       }
-      stream->Add("; ");
+      stream->Add(";");
     }
   }
 }