commit d7c2fdc939bb7efb3e7204d62e54c6a3f7d77f9b
author Nicolas Geoffray <ngeoffray@google.com> Tue May 10 14:35:34 2016 +0100
committer Nicolas Geoffray <ngeoffray@google.com> Thu May 12 08:58:12 2016 +0100
tree 692eb754d2cf5fdb81809529f02a50f2e4747a62
parent b2b55596e605bef315b615cb89e4515f360548f2

Fix another case of live_in at irreducible loop entry.

GVN was implicitly extending the liveness of an instruction across
an irreducible loop.

Fix this problem by clearing the value set at loop entries that contain
an irreducible loop.

bug:28252896

(cherry picked from commit 77ce6430af2709432b22344ed656edd8ec80581b)

Change-Id: Ie0121e83b2dfe47bcd184b90a69c0194d13fce54

compiler/optimizing/nodes.h

diff --git a/compiler/optimizing/nodes.h b/compiler/optimizing/nodes.h
index 934d355..12ea059 100644
--- a/compiler/optimizing/nodes.h
+++ b/compiler/optimizing/nodes.h
@@ -650,6 +650,7 @@
       : header_(header),
         suspend_check_(nullptr),
         irreducible_(false),
+        contains_irreducible_loop_(false),
         back_edges_(graph->GetArena()->Adapter(kArenaAllocLoopInfoBackEdges)),
         // Make bit vector growable, as the number of blocks may change.
         blocks_(graph->GetArena(), graph->GetBlocks().size(), true, kArenaAllocLoopInfoBackEdges) {
@@ -657,6 +658,7 @@
   }
 
   bool IsIrreducible() const { return irreducible_; }
+  bool ContainsIrreducibleLoop() const { return contains_irreducible_loop_; }
 
   void Dump(std::ostream& os);
 
@@ -727,6 +729,10 @@
 
   bool HasBackEdgeNotDominatedByHeader() const;
 
+  bool IsPopulated() const {
+    return blocks_.GetHighestBitSet() != -1;
+  }
+
  private:
   // Internal recursive implementation of `Populate`.
   void PopulateRecursive(HBasicBlock* block);
@@ -735,6 +741,7 @@
   HBasicBlock* header_;
   HSuspendCheck* suspend_check_;
   bool irreducible_;
+  bool contains_irreducible_loop_;
   ArenaVector<HBasicBlock*> back_edges_;
   ArenaBitVector blocks_;