schedule_(schedule),
order_(NULL),
loops_(zone),
+ beyond_end_(NULL),
backedges_(1, zone),
stack_(zone),
previous_block_count_(0) {}
// Computes the special reverse-post-order for the main control flow graph,
// that is for the graph spanned between the schedule's start and end blocks.
void ComputeSpecialRPO() {
- DCHECK(schedule_->end()->SuccessorCount() == 0);
DCHECK_EQ(NULL, order_); // Main order does not exist yet.
- ComputeAndInsertSpecialRPO(schedule_->start(), schedule_->end());
+ // TODO(mstarzinger): Should use Schedule::end() after tests are fixed.
+ ComputeAndInsertSpecialRPO(schedule_->start(), NULL);
}
// Computes the special reverse-post-order for a partial control flow graph,
l->block->set_rpo_number(number++);
schedule_->rpo_order()->push_back(l->block);
}
- if (schedule_->end()->rpo_number() < 0) {
- schedule_->end()->set_rpo_number(number);
- }
+ BeyondEndSentinel()->set_rpo_number(number);
}
// Print and verify the special reverse-post-order.
return block->ao_number() >= 0;
}
+ // TODO(mstarzinger): We only need this special sentinel because some tests
+ // use the schedule's end block in actual control flow (e.g. with end having
+ // successors). Once this has been cleaned up we can use the end block here.
+ BasicBlock* BeyondEndSentinel() {
+ if (beyond_end_ == NULL) {
+ BasicBlock::Id id = BasicBlock::Id::FromInt(-1);
+ beyond_end_ = new (schedule_->zone()) BasicBlock(schedule_->zone(), id);
+ }
+ return beyond_end_;
+ }
+
// Compute special RPO for the control flow graph between {entry} and {end},
// mutating any existing order so that the result is still valid.
void ComputeAndInsertSpecialRPO(BasicBlock* entry, BasicBlock* end) {
++loop_depth;
current_loop = &loops_[GetLoopNumber(current)];
BlockList* end = current_loop->end;
- current->set_loop_end(end == NULL ? schedule_->end() : end->block);
+ current->set_loop_end(end == NULL ? BeyondEndSentinel() : end->block);
current_header = current_loop->header;
Trace("B%d is a loop header, increment loop depth to %d\n",
current->id().ToInt(), loop_depth);
Schedule* schedule_;
BlockList* order_;
ZoneVector<LoopInfo> loops_;
+ BasicBlock* beyond_end_;
ZoneList<Backedge> backedges_;
ZoneVector<SpecialRPOStackFrame> stack_;
size_t previous_block_count_;
TEST(RPOEntryLoop) {
HandleAndZoneScope scope;
Schedule schedule(scope.main_zone());
- BasicBlock* body = schedule.NewBasicBlock();
- schedule.AddSuccessorForTesting(schedule.start(), body);
- schedule.AddSuccessorForTesting(body, schedule.start());
+ schedule.AddSuccessorForTesting(schedule.start(), schedule.end());
+ schedule.AddSuccessorForTesting(schedule.end(), schedule.start());
ZonePool zone_pool(scope.main_isolate());
BasicBlockVector* order = Scheduler::ComputeSpecialRPO(&zone_pool, &schedule);
CheckRPONumbers(order, 2, true);
- BasicBlock* loop[] = {schedule.start(), body};
+ BasicBlock* loop[] = {schedule.start(), schedule.end()};
CheckLoop(order, loop, 2);
}
BasicBlock* A = schedule.start();
BasicBlock* B = schedule.NewBasicBlock();
BasicBlock* C = schedule.NewBasicBlock();
- BasicBlock* D = schedule.NewBasicBlock();
+ BasicBlock* D = schedule.end();
BasicBlock* E = schedule.NewBasicBlock();
schedule.AddSuccessorForTesting(A, B);