1 files changed, 47 insertions, 6 deletions

diff --git a/runtime/interpreter/shadow_frame.h b/runtime/interpreter/shadow_frame.h
index 91371d1e4e..9854f8f77a 100644
--- a/runtime/interpreter/shadow_frame.h
+++ b/runtime/interpreter/shadow_frame.h
@@ -49,6 +49,17 @@ using ShadowFrameAllocaUniquePtr = std::unique_ptr<ShadowFrame, ShadowFrameDelet
 //  - interpreter - separate VRegs and reference arrays. References are in the reference array.
 //  - JNI - just VRegs, but where every VReg holds a reference.
 class ShadowFrame {
+ private:
+  // Used to keep track of extra state the shadowframe has.
+  enum class FrameFlags : uint32_t {
+    // We have been requested to notify when this frame gets popped.
+    kNotifyFramePop = 1 << 0,
+    // We have been asked to pop this frame off the stack as soon as possible.
+    kForcePopFrame  = 1 << 1,
+    // We have been asked to re-execute the last instruction.
+    kForceRetryInst = 1 << 2,
+  };
+
  public:
   // Compute size of ShadowFrame in bytes assuming it has a reference array.
   static size_t ComputeSize(uint32_t num_vregs) {
@@ -345,11 +356,27 @@ class ShadowFrame {
   }
 
   bool NeedsNotifyPop() const {
-    return needs_notify_pop_;
+    return GetFrameFlag(FrameFlags::kNotifyFramePop);
   }
 
   void SetNotifyPop(bool notify) {
-    needs_notify_pop_ = notify;
+    UpdateFrameFlag(notify, FrameFlags::kNotifyFramePop);
+  }
+
+  bool GetForcePopFrame() const {
+    return GetFrameFlag(FrameFlags::kForcePopFrame);
+  }
+
+  void SetForcePopFrame(bool enable) {
+    UpdateFrameFlag(enable, FrameFlags::kForcePopFrame);
+  }
+
+  bool GetForceRetryInstruction() const {
+    return GetFrameFlag(FrameFlags::kForceRetryInst);
+  }
+
+  void SetForceRetryInstruction(bool enable) {
+    UpdateFrameFlag(enable, FrameFlags::kForceRetryInst);
   }
 
  private:
@@ -364,7 +391,7 @@ class ShadowFrame {
         dex_pc_(dex_pc),
         cached_hotness_countdown_(0),
         hotness_countdown_(0),
-        needs_notify_pop_(0) {
+        frame_flags_(0) {
     // TODO(iam): Remove this parameter, it's an an artifact of portable removal
     DCHECK(has_reference_array);
     if (has_reference_array) {
@@ -374,6 +401,18 @@ class ShadowFrame {
     }
   }
 
+  void UpdateFrameFlag(bool enable, FrameFlags flag) {
+    if (enable) {
+      frame_flags_ |= static_cast<uint32_t>(flag);
+    } else {
+      frame_flags_ &= ~static_cast<uint32_t>(flag);
+    }
+  }
+
+  bool GetFrameFlag(FrameFlags flag) const {
+    return (frame_flags_ & static_cast<uint32_t>(flag)) != 0;
+  }
+
   const StackReference<mirror::Object>* References() const {
     DCHECK(HasReferenceArray());
     const uint32_t* vreg_end = &vregs_[NumberOfVRegs()];
@@ -397,9 +436,11 @@ class ShadowFrame {
   uint32_t dex_pc_;
   int16_t cached_hotness_countdown_;
   int16_t hotness_countdown_;
-  // TODO Might be worth it to try to bit-pack this into some other field to reduce stack usage.
-  // NB alignment requires that this field takes 4 bytes. Only 1 bit is actually ever used.
-  bool needs_notify_pop_;
+
+  // This is a set of ShadowFrame::FrameFlags which denote special states this frame is in.
+  // NB alignment requires that this field takes 4 bytes no matter its size. Only 3 bits are
+  // currently used.
+  uint32_t frame_flags_;
 
   // This is a two-part array:
   //  - [0..number_of_vregs) holds the raw virtual registers, and each element here is always 4