[wasm] Implement frame inspection for interpreted frames

src/wasm/wasm-interpreter.h

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_WASM_INTERPRETER_H_
 #define V8_WASM_INTERPRETER_H_
 
 #include "src/wasm/wasm-opcodes.h"
 #include "src/zone/zone-containers.h"
 
@@ skipping 62 matching lines @@
   }                                           \
   template <>                                 \
   inline ctype WasmVal::to() {                \
     CHECK_EQ(localtype, type);                \
     return val.field;                         \
   }
 FOREACH_UNION_MEMBER(DECLARE_CAST)
 #undef DECLARE_CAST
 
 // Representation of frames within the interpreter.
-class WasmFrame {
+class InterpretedFrame {
  public:
   const WasmFunction* function() const { return function_; }
-  int pc() const {
-    // TODO(wasm): Remove USE once we actually use them.
-    USE(fp_);
-    USE(sp_);
-    return pc_;
-  }
+  int pc() const { return pc_; }
+
+  //==========================================================================
+  // Stack frame inspection.
+  //==========================================================================
+  int GetParameterCount() const;
+  WasmVal GetLocalVal(int index) const;
+  WasmVal GetExprVal(int pc) const;
+  void SetLocalVal(int index, WasmVal val);
+  void SetExprVal(int pc, WasmVal val);
 
  private:
   friend class WasmInterpreter;
 
-  WasmFrame(const WasmFunction* function, int pc, int fp, int sp)
+  InterpretedFrame(const WasmFunction* function, int pc, int fp, int sp)
       : function_(function), pc_(pc), fp_(fp), sp_(sp) {}
 
   const WasmFunction* function_;
   int pc_;
   int fp_;
   int sp_;
 };
 
 // An interpreter capable of executing WASM.
 class V8_EXPORT_PRIVATE WasmInterpreter {
@@ skipping 20 matching lines @@
     State state();
     void PushFrame(const WasmFunction* function, WasmVal* args);
     State Run();
     State Step();
     void Pause();
     void Reset();
 
     // Stack inspection and modification.
     pc_t GetBreakpointPc();
     int GetFrameCount();
-    const WasmFrame* GetFrame(int index);
-    WasmFrame* GetMutableFrame(int index);
+    const InterpretedFrame GetFrame(int index);
+    InterpretedFrame GetMutableFrame(int index);
     WasmVal GetReturnValue(int index = 0);
     // Returns true if the thread executed an instruction which may produce
     // nondeterministic results, e.g. float div, float sqrt, and float mul,
     // where the sign bit of a NaN is nondeterministic.
     bool PossibleNondeterminism();
 
     // Thread-specific breakpoints.
     // TODO(wasm): Implement this once we support multiple threads.
     // bool SetBreakpoint(const WasmFunction* function, int pc, bool enabled);
     // bool GetBreakpoint(const WasmFunction* function, int pc);
@@ skipping 18 matching lines @@
   // Enable or disable tracing for {function}. Return the previous state.
   bool SetTracing(const WasmFunction* function, bool enabled);
 
   //==========================================================================
   // Thread iteration and inspection.
   //==========================================================================
   int GetThreadCount();
   Thread* GetThread(int id);
 
   //==========================================================================
-  // Stack frame inspection.
-  //==========================================================================
-  WasmVal GetLocalVal(const WasmFrame* frame, int index);
-  WasmVal GetExprVal(const WasmFrame* frame, int pc);
-  void SetLocalVal(WasmFrame* frame, int index, WasmVal val);
-  void SetExprVal(WasmFrame* frame, int pc, WasmVal val);
-
-  //==========================================================================
   // Memory access.
   //==========================================================================
   size_t GetMemorySize();
   WasmVal ReadMemory(size_t offset);
   void WriteMemory(size_t offset, WasmVal val);
 
   //==========================================================================
   // Testing functionality.
   //==========================================================================
   // Manually adds a function to this interpreter, returning the index of the
@@ skipping 12 matching lines @@
  private:
   Zone zone_;
   WasmInterpreterInternals* internals_;
 };
 
 }  // namespace wasm
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_WASM_INTERPRETER_H_