diff --git a/compiler/dex/bb_optimizations.h b/compiler/dex/bb_optimizations.h
index 1a90ca8..1ad4958 100644
--- a/compiler/dex/bb_optimizations.h
+++ b/compiler/dex/bb_optimizations.h
@@ -34,6 +34,10 @@
   void Start(CompilationUnit* cUnit) const {
     cUnit->mir_graph->DoCacheFieldLoweringInfo();
   }
+
+  bool Gate(const CompilationUnit *cUnit) const {
+    return cUnit->mir_graph->HasFieldAccess();
+  }
 };
 
 /**
@@ -48,6 +52,10 @@
   void Start(CompilationUnit* cUnit) const {
     cUnit->mir_graph->DoCacheMethodLoweringInfo();
   }
+
+  bool Gate(const CompilationUnit *cUnit) const {
+    return cUnit->mir_graph->HasInvokes();
+  }
 };
 
 /**
diff --git a/compiler/dex/mir_dataflow.cc b/compiler/dex/mir_dataflow.cc
index c3954fe..1c0205d 100644
--- a/compiler/dex/mir_dataflow.cc
+++ b/compiler/dex/mir_dataflow.cc
@@ -277,88 +277,88 @@
   DF_UA | DF_UB | DF_UC | DF_NULL_CHK_1 | DF_RANGE_CHK_2 | DF_REF_B | DF_CORE_C | DF_LVN,
 
   // 52 IGET vA, vB, field@CCCC
-  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_LVN,
+  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 53 IGET_WIDE vA, vB, field@CCCC
-  DF_DA | DF_A_WIDE | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_LVN,
+  DF_DA | DF_A_WIDE | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 54 IGET_OBJECT vA, vB, field@CCCC
-  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_A | DF_REF_B | DF_LVN,
+  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_A | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 55 IGET_BOOLEAN vA, vB, field@CCCC
-  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_LVN,
+  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 56 IGET_BYTE vA, vB, field@CCCC
-  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_LVN,
+  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 57 IGET_CHAR vA, vB, field@CCCC
-  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_LVN,
+  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 58 IGET_SHORT vA, vB, field@CCCC
-  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_LVN,
+  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 59 IPUT vA, vB, field@CCCC
-  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_LVN,
+  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 5A IPUT_WIDE vA, vB, field@CCCC
-  DF_UA | DF_A_WIDE | DF_UB | DF_NULL_CHK_2 | DF_REF_B | DF_LVN,
+  DF_UA | DF_A_WIDE | DF_UB | DF_NULL_CHK_2 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 5B IPUT_OBJECT vA, vB, field@CCCC
-  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_A | DF_REF_B | DF_LVN,
+  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_A | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 5C IPUT_BOOLEAN vA, vB, field@CCCC
-  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_LVN,
+  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 5D IPUT_BYTE vA, vB, field@CCCC
-  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_LVN,
+  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 5E IPUT_CHAR vA, vB, field@CCCC
-  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_LVN,
+  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 5F IPUT_SHORT vA, vB, field@CCCC
-  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_LVN,
+  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // 60 SGET vAA, field@BBBB
-  DF_DA | DF_UMS,
+  DF_DA | DF_SFIELD | DF_UMS,
 
   // 61 SGET_WIDE vAA, field@BBBB
-  DF_DA | DF_A_WIDE | DF_UMS,
+  DF_DA | DF_A_WIDE | DF_SFIELD | DF_UMS,
 
   // 62 SGET_OBJECT vAA, field@BBBB
-  DF_DA | DF_REF_A | DF_UMS,
+  DF_DA | DF_REF_A | DF_SFIELD | DF_UMS,
 
   // 63 SGET_BOOLEAN vAA, field@BBBB
-  DF_DA | DF_UMS,
+  DF_DA | DF_SFIELD | DF_UMS,
 
   // 64 SGET_BYTE vAA, field@BBBB
-  DF_DA | DF_UMS,
+  DF_DA | DF_SFIELD | DF_UMS,
 
   // 65 SGET_CHAR vAA, field@BBBB
-  DF_DA | DF_UMS,
+  DF_DA | DF_SFIELD | DF_UMS,
 
   // 66 SGET_SHORT vAA, field@BBBB
-  DF_DA | DF_UMS,
+  DF_DA | DF_SFIELD | DF_UMS,
 
   // 67 SPUT vAA, field@BBBB
-  DF_UA | DF_UMS,
+  DF_UA | DF_SFIELD | DF_UMS,
 
   // 68 SPUT_WIDE vAA, field@BBBB
-  DF_UA | DF_A_WIDE | DF_UMS,
+  DF_UA | DF_A_WIDE | DF_SFIELD | DF_UMS,
 
   // 69 SPUT_OBJECT vAA, field@BBBB
-  DF_UA | DF_REF_A | DF_UMS,
+  DF_UA | DF_REF_A | DF_SFIELD | DF_UMS,
 
   // 6A SPUT_BOOLEAN vAA, field@BBBB
-  DF_UA | DF_UMS,
+  DF_UA | DF_SFIELD | DF_UMS,
 
   // 6B SPUT_BYTE vAA, field@BBBB
-  DF_UA | DF_UMS,
+  DF_UA | DF_SFIELD | DF_UMS,
 
   // 6C SPUT_CHAR vAA, field@BBBB
-  DF_UA | DF_UMS,
+  DF_UA | DF_SFIELD | DF_UMS,
 
   // 6D SPUT_SHORT vAA, field@BBBB
-  DF_UA | DF_UMS,
+  DF_UA | DF_SFIELD | DF_UMS,
 
   // 6E INVOKE_VIRTUAL {vD, vE, vF, vG, vA}
   DF_FORMAT_35C | DF_NULL_CHK_OUT0 | DF_UMS,
@@ -712,31 +712,31 @@
   DF_DA | DF_UB | DF_CORE_A | DF_CORE_B,
 
   // E3 IGET_VOLATILE
-  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_LVN,
+  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // E4 IPUT_VOLATILE
-  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_LVN,
+  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // E5 SGET_VOLATILE
-  DF_DA | DF_UMS,
+  DF_DA | DF_SFIELD | DF_UMS,
 
   // E6 SPUT_VOLATILE
-  DF_UA | DF_UMS,
+  DF_UA | DF_SFIELD | DF_UMS,
 
   // E7 IGET_OBJECT_VOLATILE
-  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_A | DF_REF_B | DF_LVN,
+  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_REF_A | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // E8 IGET_WIDE_VOLATILE
-  DF_DA | DF_A_WIDE | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_LVN,
+  DF_DA | DF_A_WIDE | DF_UB | DF_NULL_CHK_0 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // E9 IPUT_WIDE_VOLATILE
-  DF_UA | DF_A_WIDE | DF_UB | DF_NULL_CHK_2 | DF_REF_B | DF_LVN,
+  DF_UA | DF_A_WIDE | DF_UB | DF_NULL_CHK_2 | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // EA SGET_WIDE_VOLATILE
-  DF_DA | DF_A_WIDE | DF_UMS,
+  DF_DA | DF_A_WIDE | DF_SFIELD | DF_UMS,
 
   // EB SPUT_WIDE_VOLATILE
-  DF_UA | DF_A_WIDE | DF_UMS,
+  DF_UA | DF_A_WIDE | DF_SFIELD | DF_UMS,
 
   // EC BREAKPOINT
   DF_NOP,
@@ -757,22 +757,22 @@
   DF_NOP,
 
   // F2 IGET_QUICK
-  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_LVN,
+  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_IFIELD | DF_LVN,
 
   // F3 IGET_WIDE_QUICK
-  DF_DA | DF_A_WIDE | DF_UB | DF_NULL_CHK_0 | DF_LVN,
+  DF_DA | DF_A_WIDE | DF_UB | DF_NULL_CHK_0 | DF_IFIELD | DF_LVN,
 
   // F4 IGET_OBJECT_QUICK
-  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_LVN,
+  DF_DA | DF_UB | DF_NULL_CHK_0 | DF_IFIELD | DF_LVN,
 
   // F5 IPUT_QUICK
-  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_LVN,
+  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_IFIELD | DF_LVN,
 
   // F6 IPUT_WIDE_QUICK
-  DF_UA | DF_A_WIDE | DF_UB | DF_NULL_CHK_2 | DF_LVN,
+  DF_UA | DF_A_WIDE | DF_UB | DF_NULL_CHK_2 | DF_IFIELD | DF_LVN,
 
   // F7 IPUT_OBJECT_QUICK
-  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_LVN,
+  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_IFIELD | DF_LVN,
 
   // F8 INVOKE_VIRTUAL_QUICK
   DF_FORMAT_35C | DF_NULL_CHK_OUT0 | DF_UMS,
@@ -787,13 +787,13 @@
   DF_FORMAT_3RC | DF_NULL_CHK_OUT0 | DF_UMS,
 
   // FC IPUT_OBJECT_VOLATILE
-  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_A | DF_REF_B | DF_LVN,
+  DF_UA | DF_UB | DF_NULL_CHK_1 | DF_REF_A | DF_REF_B | DF_IFIELD | DF_LVN,
 
   // FD SGET_OBJECT_VOLATILE
-  DF_DA | DF_REF_A | DF_UMS,
+  DF_DA | DF_REF_A | DF_SFIELD | DF_UMS,
 
   // FE SPUT_OBJECT_VOLATILE
-  DF_UA | DF_REF_A | DF_UMS,
+  DF_UA | DF_REF_A | DF_SFIELD | DF_UMS,
 
   // FF UNUSED_FF
   DF_NOP,
diff --git a/compiler/dex/mir_graph.cc b/compiler/dex/mir_graph.cc
index 0b50e2f..8bb5615 100644
--- a/compiler/dex/mir_graph.cc
+++ b/compiler/dex/mir_graph.cc
@@ -88,6 +88,7 @@
       num_non_special_compiler_temps_(0),
       max_available_non_special_compiler_temps_(0),
       punt_to_interpreter_(false),
+      merged_df_flags_(0u),
       ifield_lowering_infos_(arena, 0u),
       sfield_lowering_infos_(arena, 0u),
       method_lowering_infos_(arena, 0u) {
@@ -598,9 +599,11 @@
   entry_block_->fall_through = cur_block->id;
   cur_block->predecessors->Insert(entry_block_->id);
 
-    /* Identify code range in try blocks and set up the empty catch blocks */
+  /* Identify code range in try blocks and set up the empty catch blocks */
   ProcessTryCatchBlocks();
 
+  uint64_t merged_df_flags = 0u;
+
   /* Parse all instructions and put them into containing basic blocks */
   while (code_ptr < code_end) {
     MIR *insn = static_cast<MIR *>(arena_->Alloc(sizeof(MIR), kArenaAllocMIR));
@@ -617,6 +620,7 @@
     int verify_flags = Instruction::VerifyFlagsOf(insn->dalvikInsn.opcode);
 
     uint64_t df_flags = oat_data_flow_attributes_[insn->dalvikInsn.opcode];
+    merged_df_flags |= df_flags;
 
     if (df_flags & DF_HAS_DEFS) {
       def_count_ += (df_flags & DF_A_WIDE) ? 2 : 1;
@@ -715,6 +719,7 @@
       cur_block = next_block;
     }
   }
+  merged_df_flags_ = merged_df_flags;
 
   if (cu_->enable_debug & (1 << kDebugDumpCFG)) {
     DumpCFG("/sdcard/1_post_parse_cfg/", true);
diff --git a/compiler/dex/mir_graph.h b/compiler/dex/mir_graph.h
index 2abc0cc..80311ec 100644
--- a/compiler/dex/mir_graph.h
+++ b/compiler/dex/mir_graph.h
@@ -98,6 +98,8 @@
   kRefB,
   kRefC,
   kUsesMethodStar,       // Implicit use of Method*.
+  kUsesIField,           // Accesses an instance field (IGET/IPUT).
+  kUsesSField,           // Accesses a static field (SGET/SPUT).
   kDoLVN,                // Worth computing local value numbers.
 };
 
@@ -134,6 +136,8 @@
 #define DF_REF_B                (UINT64_C(1) << kRefB)
 #define DF_REF_C                (UINT64_C(1) << kRefC)
 #define DF_UMS                  (UINT64_C(1) << kUsesMethodStar)
+#define DF_IFIELD               (UINT64_C(1) << kUsesIField)
+#define DF_SFIELD               (UINT64_C(1) << kUsesSField)
 #define DF_LVN                  (UINT64_C(1) << kDoLVN)
 
 #define DF_HAS_USES             (DF_UA | DF_UB | DF_UC)
@@ -485,14 +489,23 @@
    */
   void DumpCFG(const char* dir_prefix, bool all_blocks, const char* suffix = nullptr);
 
+  bool HasFieldAccess() const {
+    return (merged_df_flags_ & (DF_IFIELD | DF_SFIELD)) != 0u;
+  }
+
+  bool HasInvokes() const {
+    // NOTE: These formats include the rare filled-new-array/range.
+    return (merged_df_flags_ & (DF_FORMAT_35C | DF_FORMAT_3RC)) != 0u;
+  }
+
   void DoCacheFieldLoweringInfo();
 
-  const MirIFieldLoweringInfo& GetIFieldLoweringInfo(MIR* mir) {
+  const MirIFieldLoweringInfo& GetIFieldLoweringInfo(MIR* mir) const {
     DCHECK_LT(mir->meta.ifield_lowering_info, ifield_lowering_infos_.Size());
     return ifield_lowering_infos_.GetRawStorage()[mir->meta.ifield_lowering_info];
   }
 
-  const MirSFieldLoweringInfo& GetSFieldLoweringInfo(MIR* mir) {
+  const MirSFieldLoweringInfo& GetSFieldLoweringInfo(MIR* mir) const {
     DCHECK_LT(mir->meta.sfield_lowering_info, sfield_lowering_infos_.Size());
     return sfield_lowering_infos_.GetRawStorage()[mir->meta.sfield_lowering_info];
   }
@@ -961,6 +974,7 @@
   size_t max_available_non_special_compiler_temps_;
   size_t max_available_special_compiler_temps_;
   bool punt_to_interpreter_;                    // Difficult or not worthwhile - just interpret.
+  uint64_t merged_df_flags_;
   GrowableArray<MirIFieldLoweringInfo> ifield_lowering_infos_;
   GrowableArray<MirSFieldLoweringInfo> sfield_lowering_infos_;
   GrowableArray<MirMethodLoweringInfo> method_lowering_infos_;