commit bc79644c1d00d200a62d968e2f193e907e45dcb4
author Mads Ager <ager@google.com> Mon Sep 11 13:02:14 2017 +0200
committer Mads Ager <ager@google.com> Mon Sep 11 13:02:14 2017 +0200
tree 3c7c86762d1aea887a2351ed5582cf7e4ff93271
parent a4d530d16b5ed0cdaad1921a8e8d540ba1c9b7ae

Fix non-deterministic iteration of live intervals.

This particular one doesn't actually lead to non-determinism in
the output because the moves are sorted in the move scheduler
as well. However, we shouldn't use the ordering based only
on start position for live intervals.

R=sgjesse@google.com

Change-Id: Idbbaa7d87b7be9e7b2ff28147981a1524eeba730

src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java

diff --git a/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java b/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java
index 1926f01..a8b3972 100644
--- a/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java
+++ b/src/main/java/com/android/tools/r8/ir/regalloc/LinearScanRegisterAllocator.java
@@ -1756,8 +1756,7 @@
     for (LiveIntervals intervals : liveIntervals) {
       if (intervals.hasSplits()) {
         LiveIntervals current = intervals;
-        PriorityQueue<LiveIntervals> sortedChildren =
-            new PriorityQueue<>((o1, o2) -> Integer.compare(o1.getStart(), o2.getStart()));
+        PriorityQueue<LiveIntervals> sortedChildren = new PriorityQueue<>();
         sortedChildren.addAll(current.getSplitChildren());
         for (LiveIntervals split = sortedChildren.poll();
             split != null;