Run HeapLocationCollector once in scheduler instead of locally.

HeapLocationCollector does alias analysis globally instead of at block
scale. For example doing it locally breaks the pre-existence based alias
analysis. It's also expensive to do it for each basic block.

Test: run-test/gtest on target/host, 662-regression-alias
Bug: 64018485
Change-Id: If001e2961b5a52b50b1bcefd5e4a89d9c25f25b8

1 files changed, 8 insertions, 8 deletions

diff --git a/compiler/optimizing/scheduler.cc b/compiler/optimizing/scheduler.cc
index 5ad011d8f9..3e373d16fb 100644
--- a/compiler/optimizing/scheduler.cc
+++ b/compiler/optimizing/scheduler.cc
@@ -554,6 +554,14 @@ SchedulingNode* CriticalPathSchedulingNodeSelector::GetHigherPrioritySchedulingN
 }
 
 void HScheduler::Schedule(HGraph* graph) {
+  // We run lsa here instead of in a separate pass to better control whether we
+  // should run the analysis or not.
+  LoadStoreAnalysis lsa(graph);
+  if (!only_optimize_loop_blocks_ || graph->HasLoops()) {
+    lsa.Run();
+    scheduling_graph_.SetHeapLocationCollector(lsa.GetHeapLocationCollector());
+  }
+
   for (HBasicBlock* block : graph->GetReversePostOrder()) {
     if (IsSchedulable(block)) {
       Schedule(block);
@@ -566,14 +574,6 @@ void HScheduler::Schedule(HBasicBlock* block) {
 
   // Build the scheduling graph.
   scheduling_graph_.Clear();
-
-  // Only perform LSA/HeapLocation analysis on the basic block that
-  // is going to get instruction scheduled.
-  HeapLocationCollector heap_location_collector(block->GetGraph());
-  heap_location_collector.VisitBasicBlock(block);
-  heap_location_collector.BuildAliasingMatrix();
-  scheduling_graph_.SetHeapLocationCollector(heap_location_collector);
-
   for (HBackwardInstructionIterator it(block->GetInstructions()); !it.Done(); it.Advance()) {
     HInstruction* instruction = it.Current();
     CHECK_EQ(instruction->GetBlock(), block)