Make special RPO computation iterative during scheduling.

src/compiler/schedule.cc

 // Copyright 2013 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/node.h"
 #include "src/compiler/node-properties.h"
 #include "src/compiler/node-properties-inl.h"
 #include "src/compiler/schedule.h"
 #include "src/ostreams.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 BasicBlock::BasicBlock(Zone* zone, Id id)
     : ao_number_(-1),
       rpo_number_(-1),
       deferred_(false),
+      dominator_depth_(-1),
       dominator_(NULL),
       loop_header_(NULL),
+      loop_end_(NULL),
       loop_depth_(0),
-      loop_end_(-1),
       control_(kNone),
       control_input_(NULL),
       nodes_(zone),
       successors_(zone),
       predecessors_(zone),
       id_(id) {}
 
 
 bool BasicBlock::LoopContains(BasicBlock* block) const {
   // RPO numbers must be initialized.
   DCHECK(rpo_number_ >= 0);
   DCHECK(block->rpo_number_ >= 0);
-  if (loop_end_ < 0) return false;  // This is not a loop.
-  return block->rpo_number_ >= rpo_number_ && block->rpo_number_ < loop_end_;
+  if (loop_end_ == NULL) return false;  // This is not a loop.
+  return block->rpo_number_ >= rpo_number_ &&
+         block->rpo_number_ < loop_end_->rpo_number_;
 }
 
 
 void BasicBlock::AddSuccessor(BasicBlock* successor) {
   successors_.push_back(successor);
 }
 
 
 void BasicBlock::AddPredecessor(BasicBlock* predecessor) {
   predecessors_.push_back(predecessor);
 }
 
 
 void BasicBlock::AddNode(Node* node) { nodes_.push_back(node); }
 
 
 void BasicBlock::set_control(Control control) {
   control_ = control;
 }
 
 
 void BasicBlock::set_control_input(Node* control_input) {
   control_input_ = control_input;
 }
 
 
+void BasicBlock::set_dominator_depth(int32_t dominator_depth) {
+  dominator_depth_ = dominator_depth;
+}
+
+
 void BasicBlock::set_dominator(BasicBlock* dominator) {
   dominator_ = dominator;
 }
 
 
 void BasicBlock::set_loop_depth(int32_t loop_depth) {
   loop_depth_ = loop_depth;
 }
 
 
 void BasicBlock::set_rpo_number(int32_t rpo_number) {
   rpo_number_ = rpo_number;
 }
 
 
-void BasicBlock::set_loop_end(int32_t loop_end) { loop_end_ = loop_end; }
+void BasicBlock::set_loop_end(BasicBlock* loop_end) { loop_end_ = loop_end; }
 
 
 void BasicBlock::set_loop_header(BasicBlock* loop_header) {
   loop_header_ = loop_header;
 }
 
 
 std::ostream& operator<<(std::ostream& os, const BasicBlock::Control& c) {
   switch (c) {
     case BasicBlock::kNone:
@@ skipping 225 matching lines @@
       }
       os << "\n";
     }
   }
   return os;
 }
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8