[TurboProp] Have BasicBlockUpdater update successor's predecessors on AddThrow.

When rewiring a block to throw, we need to remove the current block from the list
of predecessors for all of our successors, as well as clearing our current successors.

BUG=v8:9684

Change-Id: I0da063b2ef707f07ea27a5f72cabd2ff9a91cc42
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1881154Reviewed-by: Tobias Tebbi <tebbi@chromium.org>
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#64579}

src/compiler/graph-assembler.cc

@@ -270,6 +270,10 @@ void GraphAssembler::BasicBlockUpdater::AddThrow(Node* node) {
   }
   original_control_input_ = node;
   original_control_ = BasicBlock::kThrow;
+
+  for (SuccessorInfo succ : saved_successors_) {
+    succ.block->RemovePredecessor(succ.index);
+  }
   saved_successors_.clear();
 }
 

src/compiler/schedule.cc

@@ -50,6 +50,10 @@ void BasicBlock::AddPredecessor(BasicBlock* predecessor) {
   predecessors_.push_back(predecessor);
 }
 
+void BasicBlock::RemovePredecessor(size_t index) {
+  predecessors_.erase(predecessors_.begin() + index);
+}
+
 void BasicBlock::AddNode(Node* node) { nodes_.push_back(node); }
 
 void BasicBlock::set_control(Control control) { control_ = control; }

src/compiler/schedule.h

@@ -74,6 +74,7 @@ class V8_EXPORT_PRIVATE BasicBlock final
   BasicBlock* PredecessorAt(size_t index) { return predecessors_[index]; }
   void ClearPredecessors() { predecessors_.clear(); }
   void AddPredecessor(BasicBlock* predecessor);
+  void RemovePredecessor(size_t index);
 
   // Successors.
   BasicBlockVector& successors() { return successors_; }