src/emergency_malloc.h

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#ifndef EMERGENCY_MALLOC_H
#define EMERGENCY_MALLOC_H
#include "config.h"

#include <stddef.h>

#include "base/basictypes.h"
#include "common.h"

namespace tcmalloc {
  static const uintptr_t kEmergencyArenaShift = 20+4; // 16 megs
  static const uintptr_t kEmergencyArenaSize = 1 << kEmergencyArenaShift;

  extern __attribute__ ((visibility("internal"))) char *emergency_arena_start;
  extern __attribute__ ((visibility("internal"))) uintptr_t emergency_arena_start_shifted;;

  PERFTOOLS_DLL_DECL void *EmergencyMalloc(size_t size);
  PERFTOOLS_DLL_DECL void EmergencyFree(void *p);
  PERFTOOLS_DLL_DECL void *EmergencyCalloc(size_t n, size_t elem_size);
  PERFTOOLS_DLL_DECL void *EmergencyRealloc(void *old_ptr, size_t new_size);

  static inline bool IsEmergencyPtr(const void *_ptr) {
    uintptr_t ptr = reinterpret_cast<uintptr_t>(_ptr);
    return PREDICT_FALSE((ptr >> kEmergencyArenaShift) == emergency_arena_start_shifted)
      && emergency_arena_start_shifted;
  }

} // namespace tcmalloc

#endif