Revert "Revert "Enable store elimination for singleton objects.""

This reverts commit 55d02cf056f993aeafebd54e7b7c68c7a48507c9, and
makes the following change:
Currently we leverage loop side effects to decide whether heap values are
killed by the loop. Stores need to be kept if heap values may be killed
by loops and the corresponding loads cannot be eliminated. Similar thing
need to be done for each predecessor when we merge predecessor heap values.
To do that, the HInstanceFieldSet instruction itself is put in the heap
value array instead of the value of the store instruction. The store
instruction may be added to possibly_removed_stores_ first, but can later
be removed from possibly_removed_stores_ when it's found out that the store
needs to be kept due to merging/loop side effects.

Change-Id: I4f7bb1960f7b47240873e00ff1adac46fc102a02

1 files changed, 5 insertions, 2 deletions

diff --git a/compiler/driver/compiler_driver.h b/compiler/driver/compiler_driver.h
index 5683b03a71..dae785b688 100644
--- a/compiler/driver/compiler_driver.h
+++ b/compiler/driver/compiler_driver.h
@@ -211,8 +211,11 @@ class CompilerDriver {
       REQUIRES(!Locks::mutator_lock_);
 
   // Are runtime access and instantiable checks necessary in the code?
-  bool CanAccessInstantiableTypeWithoutChecks(uint32_t referrer_idx, const DexFile& dex_file,
-                                              uint32_t type_idx)
+  // out_is_finalizable is set to whether the type is finalizable.
+  bool CanAccessInstantiableTypeWithoutChecks(uint32_t referrer_idx,
+                                              const DexFile& dex_file,
+                                              uint32_t type_idx,
+                                              bool* out_is_finalizable)
       REQUIRES(!Locks::mutator_lock_);
 
   bool CanEmbedTypeInCode(const DexFile& dex_file, uint32_t type_idx,