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// stackwalker_mips.h: MIPS-specific stackwalker.
//
// Provides stack frames given MIPS register context and a memory region
// corresponding to a MIPSstack.
//
// Author: Tata Elxsi

#ifndef PROCESSOR_STACKWALKER_MIPS_H__
#define PROCESSOR_STACKWALKER_MIPS_H__

#include "google_breakpad/common/breakpad_types.h"
#include "google_breakpad/common/minidump_format.h"
#include "google_breakpad/processor/stackwalker.h"
#include "google_breakpad/processor/stack_frame_cpu.h"
#include "processor/cfi_frame_info.h"

namespace google_breakpad {

class CodeModules;

class StackwalkerMIPS : public Stackwalker {
 public:
  // Context is a MIPS context object that gives access to mips-specific
  // register state corresponding to the innermost called frame to be
  // included in the stack.  The other arguments are passed directly
  // through to the base Stackwalker constructor.
  StackwalkerMIPS(const SystemInfo* system_info,
                  const MDRawContextMIPS* context,
                  MemoryRegion* memory,
                  const CodeModules* modules,
                  StackFrameSymbolizer* frame_symbolizer);

 private:
  // Implementation of Stackwalker, using mips context and stack conventions.
  virtual StackFrame* GetContextFrame();
  virtual StackFrame* GetCallerFrame(const CallStack* stack,
                                     bool stack_scan_allowed);

  // Use cfi_frame_info (derived from STACK CFI records) to construct
  // the frame that called frames.back(). The caller takes ownership
  // of the returned frame. Return NULL on failure.
  StackFrameMIPS* GetCallerByCFIFrameInfo(const vector<StackFrame*>& frames,
                                          CFIFrameInfo* cfi_frame_info);

  // Scan the stack for plausible return address and frame pointer pair. 
  // The caller takes ownership of the returned frame. Return NULL on failure.
  StackFrameMIPS* GetCallerByStackScan(const vector<StackFrame*>& frames);

  // Stores the CPU context corresponding to the innermost stack frame to
  // be returned by GetContextFrame.
  const MDRawContextMIPS* context_;
};

}  // namespace google_breakpad

#endif  // PROCESSOR_STACKWALKER_MIPS_H__