Improve code sinking near "always throwing" method calls

Rationale:
With simple dex bytecode analysis, the inliner marks methods
that always throw to help subsequent code sinking. This reduces
overhead of non-nullable enforcing calls found in e.g the Kotlin
runtime library (1%-2% improvement on tree microbenchmark, about
5% on Denis' benchmark).

Test: test-art-host test-art-target

Change-Id: I45348f049721476828eb5443738021720d2857c0

1 files changed, 3 insertions, 1 deletions

diff --git a/compiler/optimizing/code_sinking.cc b/compiler/optimizing/code_sinking.cc
index d8ebac95a8..f4760d661f 100644
--- a/compiler/optimizing/code_sinking.cc
+++ b/compiler/optimizing/code_sinking.cc
@@ -34,7 +34,9 @@ void CodeSinking::Run() {
   // TODO(ngeoffray): we do not profile branches yet, so use throw instructions
   // as an indicator of an uncommon branch.
   for (HBasicBlock* exit_predecessor : exit->GetPredecessors()) {
-    if (exit_predecessor->GetLastInstruction()->IsThrow()) {
+    HInstruction* last = exit_predecessor->GetLastInstruction();
+    // Any predecessor of the exit that does not return, throws an exception.
+    if (!last->IsReturn() && !last->IsReturnVoid()) {
       SinkCodeToUncommonBranch(exit_predecessor);
     }
   }