Remove Frame, merge shadow and quick representations.

Change-Id: I5ae03a5e52111792d2df7e83cbd89ab25777844b
diff --git a/src/stack.h b/src/stack.h
index a26b632..26afc0a 100644
--- a/src/stack.h
+++ b/src/stack.h
@@ -18,75 +18,377 @@
 #define ART_SRC_STACK_H_
 
 #include "dex_file.h"
+#include "heap.h"
+#include "jdwp/jdwp.h"
 #include "jni.h"
 #include "macros.h"
+#include "oat/runtime/context.h"
+#include "trace.h"
 
 #include <stdint.h>
 
 namespace art {
 
 class Method;
+class Object;
+class ShadowFrame;
 class Thread;
 
 jobject GetThreadStack(JNIEnv*, Thread*);
 
-struct NativeToManagedRecord {
-  NativeToManagedRecord* link_;
-  void* last_top_of_managed_stack_;
-  uintptr_t last_top_of_managed_stack_pc_;
-};
-
-// Iterator over managed frames up to the first native-to-managed transition.
-class PACKED Frame {
+class ShadowFrame {
  public:
-  Frame() : sp_(NULL) {}
+  // Number of references contained within this shadow frame
+  uint32_t NumberOfReferences() const {
+    return number_of_references_;
+  }
 
-  explicit Frame(Method** sp) : sp_(sp) {}
+  void SetNumberOfReferences(uint32_t number_of_references) {
+    number_of_references_ = number_of_references;
+  }
+
+  // Caller dex pc
+  uint32_t GetDexPC() const {
+    return dex_pc_;
+  }
+
+  void SetDexPC(uint32_t dex_pc) {
+    dex_pc_ = dex_pc;
+  }
+
+  // Link to previous shadow frame or NULL
+  ShadowFrame* GetLink() const {
+    return link_;
+  }
+
+  void SetLink(ShadowFrame* frame) {
+    DCHECK_NE(this, frame);
+    link_ = frame;
+  }
+
+  Object* GetReference(size_t i) const {
+    DCHECK_LT(i, number_of_references_);
+    return references_[i];
+  }
+
+  void SetReference(size_t i, Object* object) {
+    DCHECK_LT(i, number_of_references_);
+    references_[i] = object;
+  }
 
   Method* GetMethod() const {
-    return (sp_ != NULL) ? *sp_ : NULL;
+    DCHECK_NE(method_, static_cast<void*>(NULL));
+    return method_;
   }
 
-  bool HasNext() const {
-    return NextMethod() != NULL;
+  void SetMethod(Method* method) {
+    DCHECK_NE(method, static_cast<void*>(NULL));
+    method_ = method;
   }
 
-  void Next();
-
-  uintptr_t GetReturnPC() const;
-
-  void SetReturnPC(uintptr_t pc);
-
-  uintptr_t LoadCalleeSave(int num) const;
-
-  static int GetVRegOffset(const DexFile::CodeItem* code_item, uint32_t core_spills,
-                           uint32_t fp_spills, size_t frame_size, int reg);
-
-  uint32_t GetVReg(const DexFile::CodeItem* code_item, uint32_t core_spills, uint32_t fp_spills,
-                    size_t frame_size, int vreg) const;
-
-  uint32_t GetVReg(Method* m, int vreg) const;
-  void SetVReg(Method* method, int vreg, uint32_t new_value);
-
-  Method** GetSP() const {
-    return sp_;
+  bool Contains(Object** shadow_frame_entry) const {
+    return ((&references_[0] <= shadow_frame_entry) &&
+            (shadow_frame_entry <= (&references_[number_of_references_ - 1])));
   }
 
-  void SetSP(Method** sp) {
-    sp_ = sp;
+  void VisitRoots(Heap::RootVisitor* visitor, void* arg) {
+    size_t num_refs = NumberOfReferences();
+    for (size_t j = 0; j < num_refs; j++) {
+      Object* object = GetReference(j);
+      if (object != NULL) {
+        visitor(object, arg);
+      }
+    }
   }
 
-  // Is this a frame for a real method (native or with dex code)
-  bool HasMethod() const;
+  // Offset of link within shadow frame
+  static size_t LinkOffset() {
+    return OFFSETOF_MEMBER(ShadowFrame, link_);
+  }
+
+  // Offset of method within shadow frame
+  static size_t MethodOffset() {
+    return OFFSETOF_MEMBER(ShadowFrame, method_);
+  }
+
+  // Offset of dex pc within shadow frame
+  static size_t DexPCOffset() {
+    return OFFSETOF_MEMBER(ShadowFrame, dex_pc_);
+  }
+
+  // Offset of length within shadow frame
+  static size_t NumberOfReferencesOffset() {
+    return OFFSETOF_MEMBER(ShadowFrame, number_of_references_);
+  }
+
+  // Offset of references within shadow frame
+  static size_t ReferencesOffset() {
+    return OFFSETOF_MEMBER(ShadowFrame, references_);
+  }
 
  private:
-  Method* NextMethod() const;
+  // ShadowFrame should be allocated by the generated code directly.
+  // We should not create new shadow stack in the runtime support function.
+  ~ShadowFrame() {}
 
-  friend class Thread;
+  uint32_t number_of_references_;
+  ShadowFrame* link_;
+  Method* method_;
+  uint32_t dex_pc_;
+  Object* references_[];
 
-  Method** sp_;
+  DISALLOW_IMPLICIT_CONSTRUCTORS(ShadowFrame);
 };
 
+// The managed stack is used to record fragments of managed code stacks. Managed code stacks
+// may either be shadow frames or lists of frames using fixed frame sizes. Transition records are
+// necessary for transitions between code using different frame layouts and transitions into native
+// code.
+class PACKED ManagedStack {
+ public:
+  ManagedStack() : link_(NULL), top_shadow_frame_(NULL),
+                   top_quick_frame_(NULL), top_quick_frame_pc_(0) {}
+  void PushManagedStackFragment(ManagedStack* fragment);
+  void PopManagedStackFragment(const ManagedStack& record);
+
+  ManagedStack* GetLink() const {
+    return link_;
+  }
+
+  Method** GetTopQuickFrame() const {
+    return top_quick_frame_;
+  }
+
+  void SetTopQuickFrame(Method** top) {
+    top_quick_frame_ = top;
+  }
+
+  uintptr_t GetTopQuickFramePc() const {
+    return top_quick_frame_pc_;
+  }
+
+  void SetTopQuickFramePc(uintptr_t pc) {
+    top_quick_frame_pc_ = pc;
+  }
+
+  static size_t TopQuickFrameOffset() {
+    return OFFSETOF_MEMBER(ManagedStack, top_quick_frame_);
+  }
+
+  static size_t TopQuickFramePcOffset() {
+    return OFFSETOF_MEMBER(ManagedStack, top_quick_frame_pc_);
+  }
+
+  ShadowFrame* PushShadowFrame(ShadowFrame* new_top_frame) {
+    ShadowFrame* old_frame = top_shadow_frame_;
+    top_shadow_frame_ = new_top_frame;
+    new_top_frame->SetLink(old_frame);
+    return old_frame;
+  }
+
+  ShadowFrame* PopShadowFrame() {
+    CHECK(top_shadow_frame_ != NULL);
+    ShadowFrame* frame = top_shadow_frame_;
+    top_shadow_frame_ = frame->GetLink();
+    return frame;
+  }
+
+  ShadowFrame* GetTopShadowFrame() const {
+    return top_shadow_frame_;
+  }
+
+  static size_t TopShadowFrameOffset() {
+    return OFFSETOF_MEMBER(ManagedStack, top_shadow_frame_);
+  }
+
+  size_t NumShadowFrameReferences() const;
+
+  bool ShadowFramesContain(Object** shadow_frame_entry) const;
+
+ private:
+  ManagedStack* link_;
+  ShadowFrame* top_shadow_frame_;
+  Method** top_quick_frame_;
+  uintptr_t top_quick_frame_pc_;
+};
+
+class StackVisitor {
+ protected:
+  StackVisitor(const ManagedStack* stack, const std::vector<TraceStackFrame>* trace_stack,
+               Context* context = NULL) :
+    stack_start_(stack), trace_stack_(trace_stack), cur_shadow_frame_(NULL), cur_quick_frame_(NULL),
+    cur_quick_frame_pc_(0), num_frames_(0), cur_depth_(0), context_(context) {}
+
+ public:
+  virtual ~StackVisitor() {}
+
+  // Return 'true' if we should continue to visit more frames, 'false' to stop.
+  virtual bool VisitFrame() = 0;
+
+  void WalkStack(bool include_transitions = false);
+
+  Method* GetMethod() const {
+    if (cur_shadow_frame_ != NULL) {
+      return cur_shadow_frame_->GetMethod();
+    } else if (cur_quick_frame_ != NULL) {
+      return *cur_quick_frame_;
+    } else {
+      return NULL;
+    }
+  }
+
+  bool IsShadowFrame() const {
+    return cur_shadow_frame_ != NULL;
+  }
+
+  uintptr_t LoadCalleeSave(int num, size_t frame_size) const {
+    // Callee saves are held at the top of the frame
+    Method* method = GetMethod();
+    DCHECK(method != NULL);
+    byte* save_addr =
+        reinterpret_cast<byte*>(cur_quick_frame_) + frame_size - ((num + 1) * kPointerSize);
+#if defined(__i386__)
+    save_addr -= kPointerSize;  // account for return address
+#endif
+    return *reinterpret_cast<uintptr_t*>(save_addr);
+  }
+
+  uint32_t GetDexPc() const;
+
+  // Gets the height of the stack in the managed stack frames, including transitions.
+  size_t GetFrameHeight() {
+    return GetNumFrames() - cur_depth_;
+  }
+
+  // Get a frame ID where 0 is a special value.
+  size_t GetFrameId() {
+    return GetFrameHeight() + 1;
+  }
+
+  size_t GetNumFrames() {
+    if (num_frames_ == 0) {
+      num_frames_ = ComputeNumFrames();
+    }
+    return num_frames_;
+  }
+
+  uint32_t GetVReg(Method* m, int vreg) const;
+
+  void SetVReg(Method* m, int vreg, uint32_t new_value);
+
+  uintptr_t GetGPR(uint32_t reg) const;
+
+  uint32_t GetVReg(const DexFile::CodeItem* code_item, uint32_t core_spills,
+                   uint32_t fp_spills, size_t frame_size, int vreg) const {
+    int offset = GetVRegOffset(code_item, core_spills, fp_spills, frame_size, vreg);
+    byte* vreg_addr = reinterpret_cast<byte*>(GetCurrentQuickFrame()) + offset;
+    return *reinterpret_cast<uint32_t*>(vreg_addr);
+  }
+
+  uintptr_t GetReturnPc() const;
+
+  void SetReturnPc(uintptr_t new_ret_pc);
+
+  /*
+   * Return sp-relative offset for a Dalvik virtual register, compiler
+   * spill or Method* in bytes using Method*.
+   * Note that (reg >= 0) refers to a Dalvik register, (reg == -2)
+   * denotes Method* and (reg <= -3) denotes a compiler temp.
+   *
+   *     +------------------------+
+   *     | IN[ins-1]              |  {Note: resides in caller's frame}
+   *     |       .                |
+   *     | IN[0]                  |
+   *     | caller's Method*       |
+   *     +========================+  {Note: start of callee's frame}
+   *     | core callee-save spill |  {variable sized}
+   *     +------------------------+
+   *     | fp callee-save spill   |
+   *     +------------------------+
+   *     | filler word            |  {For compatibility, if V[locals-1] used as wide
+   *     +------------------------+
+   *     | V[locals-1]            |
+   *     | V[locals-2]            |
+   *     |      .                 |
+   *     |      .                 |  ... (reg == 2)
+   *     | V[1]                   |  ... (reg == 1)
+   *     | V[0]                   |  ... (reg == 0) <---- "locals_start"
+   *     +------------------------+
+   *     | Compiler temps         |  ... (reg == -2)
+   *     |                        |  ... (reg == -3)
+   *     |                        |  ... (reg == -4)
+   *     +------------------------+
+   *     | stack alignment padding|  {0 to (kStackAlignWords-1) of padding}
+   *     +------------------------+
+   *     | OUT[outs-1]            |
+   *     | OUT[outs-2]            |
+   *     |       .                |
+   *     | OUT[0]                 |
+   *     | curMethod*             |  ... (reg == -1) <<== sp, 16-byte aligned
+   *     +========================+
+   */
+  static int GetVRegOffset(const DexFile::CodeItem* code_item,
+                    uint32_t core_spills, uint32_t fp_spills,
+                    size_t frame_size, int reg) {
+    DCHECK_EQ(frame_size & (kStackAlignment - 1), 0U);
+    int num_spills = __builtin_popcount(core_spills) + __builtin_popcount(fp_spills) + 1; // Filler.
+    int num_ins = code_item->ins_size_;
+    int num_regs = code_item->registers_size_ - num_ins;
+    int locals_start = frame_size - ((num_spills + num_regs) * sizeof(uint32_t));
+    if (reg == -2) {
+      return 0;  // Method*
+    } else if (reg <= -3) {
+      return locals_start - ((reg + 1) * sizeof(uint32_t));  // Compiler temp.
+    } else if (reg < num_regs) {
+      return locals_start + (reg * sizeof(uint32_t));        // Dalvik local reg.
+    } else {
+      return frame_size + ((reg - num_regs) * sizeof(uint32_t)) + sizeof(uint32_t); // Dalvik in.
+    }
+  }
+
+  uintptr_t GetCurrentQuickFramePc() const {
+    return cur_quick_frame_pc_;
+  }
+
+  Method** GetCurrentQuickFrame() const {
+    return cur_quick_frame_;
+  }
+
+  ShadowFrame* GetCurrentShadowFrame() const {
+    return cur_shadow_frame_;
+  }
+
+ private:
+  size_t ComputeNumFrames() const;
+
+  TraceStackFrame GetTraceStackFrame(uint32_t depth) const {
+    return trace_stack_->at(trace_stack_->size() - depth - 1);
+  }
+
+  void SanityCheckFrame();
+
+  const ManagedStack* const stack_start_;
+  const std::vector<TraceStackFrame>* const trace_stack_;
+  ShadowFrame* cur_shadow_frame_;
+  Method** cur_quick_frame_;
+  uintptr_t cur_quick_frame_pc_;
+  // Lazily computed, number of frames in the stack.
+  size_t num_frames_;
+  // Depth of the frame we're currently at.
+  size_t cur_depth_;
+ protected:
+  Context* const context_;
+};
+
+static inline uintptr_t AdjustQuickFramePcForDexPcComputation(uintptr_t pc) {
+  // Quick methods record a mapping from quick PCs to Dex PCs at the beginning of the code for
+  // each dex instruction. When walking the stack, the return PC will be set to the instruction
+  // following call which will likely be the start of the next dex instruction. Adjust the PC
+  // for these cases by 2 bytes in case the return PC also has the thumb bit set.
+  if (pc > 0) { pc -= 2; }
+  return pc;
+}
+
 }  // namespace art
 
 #endif  // ART_SRC_STACK_H_