Some micro-optimizations in the scheduler.

R=bmeurer@chromium.org

Review URL: https://codereview.chromium.org/764533003

Cr-Commit-Position: refs/heads/master@{#25523}

src/compiler/schedule.cc

@@ -62,16 +62,6 @@ void BasicBlock::set_control_input(Node* 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;
 }

src/compiler/schedule.h

@@ -146,10 +146,10 @@ class BasicBlock FINAL : public ZoneObject {
   void set_deferred(bool deferred) { deferred_ = deferred; }
 
   int32_t dominator_depth() const { return dominator_depth_; }
-  void set_dominator_depth(int32_t dominator_depth);
+  void set_dominator_depth(int32_t depth) { dominator_depth_ = depth; }
 
   BasicBlock* dominator() const { return dominator_; }
-  void set_dominator(BasicBlock* dominator);
+  void set_dominator(BasicBlock* dominator) { dominator_ = dominator; }
 
   BasicBlock* loop_header() const { return loop_header_; }
   void set_loop_header(BasicBlock* loop_header);

src/compiler/scheduler.cc

@@ -1063,9 +1063,9 @@ void Scheduler::GenerateImmediateDominatorTree() {
   // Build the block dominator tree.
   schedule_->start()->set_dominator_depth(0);
   typedef SpecialRPONumberer::BlockList BlockList;
-  for (BlockList* l = special_rpo_->order_; l != NULL; l = l->next) {
+  DCHECK_EQ(schedule_->start(), special_rpo_->order_->block);
+  for (BlockList* l = special_rpo_->order_->next; l != NULL; l = l->next) {
     BasicBlock* current = l->block;
-    if (current == schedule_->start()) continue;
     BasicBlock::Predecessors::iterator pred = current->predecessors_begin();
     BasicBlock::Predecessors::iterator end = current->predecessors_end();
     DCHECK(pred != end);  // All blocks except start have predecessors.