1 files changed, 14 insertions, 92 deletions

diff --git a/chromium/v8/src/compiler/graph-assembler.cc b/chromium/v8/src/compiler/graph-assembler.cc
index 6057f1ce649..c25930150ed 100644
--- a/chromium/v8/src/compiler/graph-assembler.cc
+++ b/chromium/v8/src/compiler/graph-assembler.cc
@@ -32,7 +32,6 @@ class GraphAssembler::BasicBlockUpdater {
   void AddBranch(Node* branch, BasicBlock* tblock, BasicBlock* fblock);
   void AddGoto(BasicBlock* to);
   void AddGoto(BasicBlock* from, BasicBlock* to);
-  void AddThrow(Node* node);
 
   void StartBlock(BasicBlock* block);
   BasicBlock* Finalize(BasicBlock* original);
@@ -268,92 +267,6 @@ void GraphAssembler::BasicBlockUpdater::AddGoto(BasicBlock* from,
   current_block_ = nullptr;
 }
 
-void GraphAssembler::BasicBlockUpdater::RemoveSuccessorsFromSchedule() {
-  ZoneSet<BasicBlock*> blocks(temp_zone());
-  ZoneQueue<BasicBlock*> worklist(temp_zone());
-
-  for (SuccessorInfo succ : saved_successors_) {
-    BasicBlock* block = succ.block;
-    block->predecessors().erase(block->predecessors().begin() + succ.index);
-    blocks.insert(block);
-    worklist.push(block);
-  }
-  saved_successors_.clear();
-
-  // Walk through blocks until we get to the end node, then remove the path from
-  // end, clearing their successors / predecessors.
-  // This works because the unreachable paths form self-contained control flow
-  // that doesn't re-merge with reachable control flow (checked below) and
-  // DeadCodeElimination::ReduceEffectPhi preventing Unreachable from going into
-  // an effect-phi. We would need to extend this if we need the ability to mark
-  // control flow as unreachable later in the pipeline.
-  while (!worklist.empty()) {
-    BasicBlock* current = worklist.front();
-    worklist.pop();
-
-    for (BasicBlock* successor : current->successors()) {
-      // Remove the block from sucessors predecessors.
-      ZoneVector<BasicBlock*>& predecessors = successor->predecessors();
-      auto it = std::find(predecessors.begin(), predecessors.end(), current);
-      DCHECK_EQ(*it, current);
-      predecessors.erase(it);
-
-      if (successor == schedule_->end()) {
-        // If we have reached the end block, remove this block's control input
-        // from the end node's control inputs.
-        DCHECK_EQ(current->SuccessorCount(), 1);
-        NodeProperties::RemoveControlFromEnd(graph_, common_,
-                                             current->control_input());
-      } else {
-        // Otherwise, add successor to worklist if it's not already been seen.
-        if (blocks.insert(successor).second) {
-          worklist.push(successor);
-        }
-      }
-    }
-    current->ClearSuccessors();
-  }
-
-#ifdef DEBUG
-  // Ensure that the set of blocks being removed from the schedule are self
-  // contained, i.e., all predecessors have been removed from these blocks.
-  for (BasicBlock* block : blocks) {
-    CHECK_EQ(block->PredecessorCount(), 0);
-    CHECK_EQ(block->SuccessorCount(), 0);
-  }
-#endif
-}
-
-void GraphAssembler::BasicBlockUpdater::AddThrow(Node* node) {
-  if (state_ == kUnchanged) {
-    CopyForChange();
-  }
-
-  // Clear original successors and replace the block's original control and
-  // control input to the throw, since this block is now connected directly to
-  // the end.
-  if (original_control_input_ != nullptr) {
-    NodeProperties::ReplaceUses(original_control_input_, node, nullptr, node);
-    original_control_input_->Kill();
-  }
-  original_control_input_ = node;
-  original_control_ = BasicBlock::kThrow;
-
-  bool already_connected_to_end =
-      saved_successors_.size() == 1 &&
-      saved_successors_[0].block == schedule_->end();
-  if (!already_connected_to_end) {
-    // Remove all successor blocks from the schedule.
-    RemoveSuccessorsFromSchedule();
-
-    // Update current block's successor withend.
-    DCHECK(saved_successors_.empty());
-    size_t index = schedule_->end()->predecessors().size();
-    schedule_->end()->AddPredecessor(current_block_);
-    saved_successors_.push_back({schedule_->end(), index});
-  }
-}
-
 void GraphAssembler::BasicBlockUpdater::UpdateSuccessors(BasicBlock* block) {
   for (SuccessorInfo succ : saved_successors_) {
     (succ.block->predecessors())[succ.index] = block;
@@ -716,6 +629,11 @@ Node* GraphAssembler::Unreachable() {
       graph()->NewNode(common()->Unreachable(), effect(), control()));
 }
 
+TNode<RawPtrT> GraphAssembler::StackSlot(int size, int alignment) {
+  return AddNode<RawPtrT>(
+      graph()->NewNode(machine()->StackSlot(size, alignment)));
+}
+
 Node* GraphAssembler::Store(StoreRepresentation rep, Node* object, Node* offset,
                             Node* value) {
   return AddNode(graph()->NewNode(machine()->Store(rep), object, offset, value,
@@ -906,11 +824,15 @@ BasicBlock* GraphAssembler::FinalizeCurrentBlock(BasicBlock* block) {
 
 void GraphAssembler::ConnectUnreachableToEnd() {
   DCHECK_EQ(effect()->opcode(), IrOpcode::kUnreachable);
-  Node* throw_node = graph()->NewNode(common()->Throw(), effect(), control());
-  NodeProperties::MergeControlToEnd(graph(), common(), throw_node);
-  effect_ = control_ = mcgraph()->Dead();
-  if (block_updater_) {
-    block_updater_->AddThrow(throw_node);
+  // When maintaining the schedule we can't easily rewire the successor blocks
+  // to disconnect them from the graph, so we just leave the unreachable nodes
+  // in the schedule.
+  // TODO(9684): Add a scheduled dead-code elimination phase to remove all the
+  // subsiquent unreacahble code from the schedule.
+  if (!block_updater_) {
+    Node* throw_node = graph()->NewNode(common()->Throw(), effect(), control());
+    NodeProperties::MergeControlToEnd(graph(), common(), throw_node);
+    effect_ = control_ = mcgraph()->Dead();
   }
 }