Tweak liveness when instructions are used in environments.

Instructions remain live when debuggable, but only instructions
with object types remain live when non-debuggable.

Enable StackVisitor::GetThisObject for optimizing.

Change-Id: Id87b2cbf33a02450059acc9993995782e5f28987

1 files changed, 3 insertions, 2 deletions

diff --git a/compiler/optimizing/ssa_liveness_analysis.cc b/compiler/optimizing/ssa_liveness_analysis.cc
index d009390..c0d6f42 100644
--- a/compiler/optimizing/ssa_liveness_analysis.cc
+++ b/compiler/optimizing/ssa_liveness_analysis.cc
@@ -230,11 +230,12 @@ void SsaLivenessAnalysis::ComputeLiveRanges() {
       }
 
       if (current->HasEnvironment()) {
-        // All instructions in the environment must be live.
+        // Handle environment uses. See statements (b) and (c) of the
+        // SsaLivenessAnalysis.
         HEnvironment* environment = current->GetEnvironment();
         for (size_t i = 0, e = environment->Size(); i < e; ++i) {
           HInstruction* instruction = environment->GetInstructionAt(i);
-          if (instruction != nullptr) {
+          if (ShouldBeLiveForEnvironment(instruction)) {
             DCHECK(instruction->HasSsaIndex());
             live_in->SetBit(instruction->GetSsaIndex());
             instruction->GetLiveInterval()->AddUse(current, i, true);