commit badee9820fcf5dca5f8c46c3215ae1779ee7736e
author Nelli Kim <nelli.kim@samsung.com> Fri May 13 13:08:53 2016 +0300
committer Matthew Gharrity <gharrma@google.com> Tue Jun 14 10:05:47 2016 -0700
tree 982948a67a88a1f9a734c935f919f8d307969f48
parent 614968198625a6693666bdc1e5609e2f663f5638

Optimize IMT

* Remove IMT for classes which do not implement interfaces
* Remove IMT for array classes
* Share same IMT

Saved memory (measured on hammerhead):
boot.art:
Total number of classes: 3854
Number of affected classes: 1637
Saved memory: 409kB

Chrome (excluding classes in boot.art):
Total number of classes: 2409
Number of affected classes: 1259
Saved memory: 314kB

Google Maps (excluding classes in boot.art):
Total number of classes: 6988
Number of affected classes: 2574
Saved memory: 643kB

Performance regression on benchmarks/InvokeInterface.java benchmark
(measured timeCall10Interface)
1st launch: 9.6%
2nd launch: 6.8%

Change-Id: If07e45390014a6ee8f3c1c4ca095b43046f0871f

compiler/image_writer.h

diff --git a/compiler/image_writer.h b/compiler/image_writer.h
index 51976c5..1efdc22 100644
--- a/compiler/image_writer.h
+++ b/compiler/image_writer.h
@@ -169,6 +169,8 @@
     // ArtMethods may be dirty if the class has native methods or a declaring class that isn't
     // initialized.
     kBinArtMethodDirty,
+    // IMT (clean)
+    kBinImTable,
     // Conflict tables (clean).
     kBinIMTConflictTable,
     // Runtime methods (always clean, do not have a length prefix array).
@@ -191,6 +193,7 @@
     kNativeObjectRelocationTypeArtMethodDirty,
     kNativeObjectRelocationTypeArtMethodArrayDirty,
     kNativeObjectRelocationTypeRuntimeMethod,
+    kNativeObjectRelocationTypeIMTable,
     kNativeObjectRelocationTypeIMTConflictTable,
     kNativeObjectRelocationTypeDexCacheArray,
   };
@@ -401,6 +404,7 @@
   void CopyAndFixupObject(mirror::Object* obj) SHARED_REQUIRES(Locks::mutator_lock_);
   void CopyAndFixupMethod(ArtMethod* orig, ArtMethod* copy, const ImageInfo& image_info)
       SHARED_REQUIRES(Locks::mutator_lock_);
+  void CopyAndFixupImTable(ImTable* orig, ImTable* copy) SHARED_REQUIRES(Locks::mutator_lock_);
   void CopyAndFixupImtConflictTable(ImtConflictTable* orig, ImtConflictTable* copy)
       SHARED_REQUIRES(Locks::mutator_lock_);
   void FixupClass(mirror::Class* orig, mirror::Class* copy)
@@ -433,6 +437,8 @@
                           size_t oat_index)
       SHARED_REQUIRES(Locks::mutator_lock_);
 
+  void TryAssignImTableOffset(ImTable* imt, size_t oat_index) SHARED_REQUIRES(Locks::mutator_lock_);
+
   // Assign the offset for an IMT conflict table. Does nothing if the table already has a native
   // relocation.
   void TryAssignConflictTableOffset(ImtConflictTable* table, size_t oat_index)