



#ifndef NTL_tools__H
#define NTL_tools__H

//#define NTL_TEST_EXCEPTIONS

#include <NTL/ctools.h>
#include <NTL/new.h>

#include <utility>
#include <iostream>
#include <new>
#include <stdexcept>
#include <streambuf>

#include <cstdlib>
#include <cmath>
#include <cstring>

#ifdef NTL_SAFE_VECTORS

#include <type_traits>

#endif


#if (defined(NTL_THREADS) && defined(NTL_TLS_HACK)) 
#include <pthread.h>
#endif




#define NTL_SNS std ::
#define NTL_USE_SNS using namespace std;

#define NTL_IMPORT_FROM_STD \
   using NTL_SNS abs; \
   using NTL_SNS ceil; \
   using NTL_SNS exp; \
   using NTL_SNS fabs; \
   using NTL_SNS floor; \
   using NTL_SNS ldexp; \
   using NTL_SNS log; \
   using NTL_SNS sqrt; \
   using NTL_SNS ostream;  \
   using NTL_SNS istream;  \
   using NTL_SNS cerr;  \
   using NTL_SNS ifstream;  \
   using NTL_SNS ofstream; 



#ifndef NTL_LEGACY_NO_NAMESPACE

// This wraps NTL in the NTL namespace.
// This is the current default.

#define NTL_NAMESPACE NTL
#define NTL_OPEN_NNS namespace NTL_NAMESPACE {
#define NTL_CLOSE_NNS  }
#define NTL_USE_NNS using namespace NTL_NAMESPACE;
#define NTL_NNS NTL_NAMESPACE ::

// To make things work, we have to apply using declarations of all std
// functions that are both overloaded by NTL and are used in
// the implementation of NTL.

#define NTL_START_IMPL NTL_OPEN_NNS NTL_IMPORT_FROM_STD


#define NTL_END_IMPL NTL_CLOSE_NNS

#else

// This puts NTL in the global namespace.
// Provided only for backward compatibility.

#define NTL_NAMESPACE 
#define NTL_OPEN_NNS 
#define NTL_CLOSE_NNS 
#define NTL_USE_NNS 
#define NTL_NNS 

#define NTL_START_IMPL NTL_IMPORT_FROM_STD
#define NTL_END_IMPL

#endif

#define NTL_CLIENT NTL_USE_SNS NTL_USE_NNS



double _ntl_GetTime();
unsigned long _ntl_GetPID();

typedef unsigned long _ntl_ulong;
typedef _ntl_ulong *_ntl_ulong_ptr;
// I made these have "obscure" names to avoid conflict with
// (non-standard but common) definitions in standard headers.
// Putting u_long inside namespace NTL only tends to creates ambiguities,
// for no good reason.




NTL_OPEN_NNS

#ifndef NTL_LEGACY_INPUT_ERROR

// this newer version is more in line with wider C++
// practice, setting the "fail bit" of an input stream
// when an error is encounted.  This is now the default in NTL

#define NTL_INPUT_ERROR(s, msg) \
   do {\
      s.setstate(NTL_SNS ios::failbit);\
      return s;\
   } while (0)\


#else

// this version provides full backward compatibility,
// raising an error on ill-formed or missing input

#define NTL_INPUT_ERROR(s, msg) \
   do {\
      InputError(msg);\
   } while (0)\


#endif


#define NTL_INPUT_CHECK_ERR(stmt) \
   do {\
      if (!(stmt)) InputError("bad input\n");\
   } while (0)\



#define NTL_INPUT_CHECK_RET(s, stmt) \
   do {\
      if (!(stmt)) { s.setstate(NTL_SNS ios::failbit); return s; }\
   } while (0)\





#define NTL_FILE_THRESH (1e12)
// threshold in KB for switching to external storage of certain tables 




struct INIT_SIZE_STRUCT { };
const INIT_SIZE_STRUCT INIT_SIZE = INIT_SIZE_STRUCT();
typedef const INIT_SIZE_STRUCT& INIT_SIZE_TYPE;

struct INIT_VAL_STRUCT { };
const INIT_VAL_STRUCT INIT_VAL = INIT_VAL_STRUCT();
typedef const INIT_VAL_STRUCT& INIT_VAL_TYPE;

struct INIT_TRANS_STRUCT { };
const INIT_TRANS_STRUCT INIT_TRANS = INIT_TRANS_STRUCT();
typedef const INIT_TRANS_STRUCT& INIT_TRANS_TYPE;


struct INIT_LOOP_HOLE_STRUCT { };
const INIT_LOOP_HOLE_STRUCT INIT_LOOP_HOLE = INIT_LOOP_HOLE_STRUCT();
typedef const INIT_LOOP_HOLE_STRUCT& INIT_LOOP_HOLE_TYPE;

struct INIT_FFT_STRUCT { };
const INIT_FFT_STRUCT INIT_FFT = INIT_FFT_STRUCT();
typedef const INIT_FFT_STRUCT& INIT_FFT_TYPE;

struct INIT_USER_FFT_STRUCT { };
const INIT_USER_FFT_STRUCT INIT_USER_FFT = INIT_USER_FFT_STRUCT();
typedef const INIT_USER_FFT_STRUCT& INIT_USER_FFT_TYPE;

struct INIT_NO_ALLOC_STRUCT { };
const INIT_NO_ALLOC_STRUCT INIT_NO_ALLOC = INIT_NO_ALLOC_STRUCT();
typedef const INIT_NO_ALLOC_STRUCT& INIT_NO_ALLOC_TYPE;

struct INIT_ALLOC_STRUCT { };
const INIT_ALLOC_STRUCT INIT_ALLOC = INIT_ALLOC_STRUCT();
typedef const INIT_ALLOC_STRUCT& INIT_ALLOC_TYPE;

struct INIT_MONO_STRUCT { };
const INIT_MONO_STRUCT INIT_MONO = INIT_MONO_STRUCT();
typedef const INIT_MONO_STRUCT& INIT_MONO_TYPE;



#ifdef NTL_NO_INIT_TRANS
#define NTL_OPT_RETURN(t, x) return x
#else
#define NTL_OPT_RETURN(t, x) return t(x, INIT_TRANS)
#endif


#ifndef NTL_NO_MIN_MAX

inline int min(int a, int b) { return (a < b) ?  a : b; } 
inline int max(int a, int b) { return (a < b) ? b : a; }

inline long min(long a, long b) { return (a < b) ?  a : b; } 
inline long max(long a, long b) { return (a < b) ? b : a; }

inline long min(int a, long b) { return (a < b) ?  long(a) : b; } 
inline long max(int a, long b) { return (a < b) ? b : long(a); }

inline long min(long a, int b) { return (a < b) ?  a : long(b); } 
inline long max(long a, int b) { return (a < b) ? long(b) : a; }

inline unsigned int min(unsigned int a, unsigned int b) 
{ return (a < b) ?  a : b; } 
inline unsigned int max(unsigned int a, unsigned int b) 
{ return (a < b) ? b : a; }

inline unsigned long min(unsigned long a, unsigned long b) 
{ return (a < b) ?  a : b; } 
inline unsigned long max(unsigned long a, unsigned long b) 
{ return (a < b) ? b : a; }

inline unsigned long min(unsigned int a, unsigned long b) 
{ return (a < b) ?  (unsigned long)(a) : b; } 
inline unsigned long max(unsigned int a, unsigned long b) 
{ return (a < b) ? b : (unsigned long)(a); }

inline unsigned long min(unsigned long a, unsigned int b) 
{ return (a < b) ?  a : (unsigned long)(b); } 
inline unsigned long max(unsigned long a, unsigned int b) 
{ return (a < b) ? (unsigned long)(b) : a; }

#endif


// NOTE: these are here for historical reasons, so I'll leave them
// Since it is likely to lead to ambiguities with std::swap,
// I am not defining any more of these.  
inline void swap(long& a, long& b)  {  long t;  t = a; a = b; b = t; }
inline void swap(int& a, int& b)  {  int t;  t = a; a = b; b = t; }


// some convenience casting routines:

inline unsigned long cast_unsigned(long a) { return (unsigned long) a; }
inline unsigned int cast_unsigned(int a) { return (unsigned int) a; }


// these routines respect the NTL_CLEAN_INT flag: if set,
// they use code that is guaranteed to work, under the
// assumption that signed integers are two's complement.
// A good compiler should optimize it all away and generate
// the same code in either case (tested on gcc, clang, icc, msvc++).
// This is really an academic exercise...

#ifdef NTL_CLEAN_INT

inline long cast_signed(unsigned long a) 
{ return NTL_ULONG_TO_LONG(a); }

inline int cast_signed(unsigned int a) 
{ return NTL_UINT_TO_INT(a); }

#else

inline long cast_signed(unsigned long a) { return long(a); }
inline int cast_signed(unsigned int a) { return int(a); }

#endif


inline void conv(int& x, int a) { x = a; }
inline void conv(int& x, long a) 
   { unsigned y = (unsigned) a;  x = cast_signed(y); }
inline void conv(int& x, float a) { x = int(NTL_SNS floor(double(a))); }
inline void conv(int& x, double a) { x = int(NTL_SNS floor(a)); }

inline void conv(int& x, unsigned a) 
   { x = cast_signed(a); }

inline void conv(int& x, unsigned long a)
   { unsigned y = (unsigned) a;  x = cast_signed(y); }

inline int to_int(int a) { return a; }
inline int to_int(long a) 
   { unsigned y = (unsigned) a;  return cast_signed(y); }
inline int to_int(float a) { return int(NTL_SNS floor(double(a))); }
inline int to_int(double a) { return int(NTL_SNS floor(a)); }

inline int to_int(unsigned a) 
   { return cast_signed(a); }

inline int to_int(unsigned long a) 
   { unsigned y = (unsigned) a;  return cast_signed(y); }


inline void conv(long& x, int a) { x = a; }
inline void conv(long& x, long a) { x = a; }
inline void conv(long& x, float a) { x = long(NTL_SNS floor(double(a))); }
inline void conv(long& x, double a) { x = long(NTL_SNS floor(a)); }

inline void conv(long& x, unsigned a)
   { unsigned long y = a;  x = cast_signed(y); }

inline void conv(long& x, unsigned long a)
   { x = cast_signed(a); }

inline long to_long(int a) { return a; }
inline long to_long(long a) { return a; }
inline long to_long(float a) { return long(NTL_SNS floor(double(a))); }
inline long to_long(double a) { return long(NTL_SNS floor(a)); }

inline long to_long(unsigned a)
   { unsigned long y = a;  return cast_signed(y); }

inline long to_long(unsigned long a)
   { return cast_signed(a); }

inline void conv(float& x, int a) { x = float(a); }
inline void conv(float& x, long a) { x = float(a); }
inline void conv(float& x, unsigned a) { x = float(a); }
inline void conv(float& x, unsigned long a) { x = float(a); }
inline void conv(float& x, float a) { x = a; }
inline void conv(float& x, double a) { x = float(a); }

inline float to_float(int a) { return float(a); }
inline float to_float(long a) { return float(a); }
inline float to_float(unsigned a) { return float(a); }
inline float to_float(unsigned long a) { return float(a); }
inline float to_float(float a) { return a; }
inline float to_float(double a) { return float(a); }

inline void conv(double& x, int a) { x = double(a); }
inline void conv(double& x, long a) { x = double(a); }
inline void conv(double& x, unsigned a) { x = double(a); }
inline void conv(double& x, unsigned long a) { x = double(a); }
inline void conv(double& x, float a) { x = double(a); }
inline void conv(double& x, double a) { x = a; }

inline double to_double(int a) { return double(a); }
inline double to_double(long a) { return double(a); }
inline double to_double(unsigned a) { return double(a); }
inline double to_double(unsigned long a) { return double(a); }
inline double to_double(float a) { return double(a); }
inline double to_double(double a) { return a; }



/* additional legacy conversions for v6 conversion regime */


inline void conv(unsigned int& x, int a) { x = ((unsigned int)(a)); }
inline void conv(unsigned int& x, long a) { x = ((unsigned int)(a)); }
inline void conv(unsigned int& x, unsigned a) { x = a; }
inline void conv(unsigned int& x, unsigned long a) { x = ((unsigned int)(a)); }
inline void conv(unsigned int& x, float a) { x = ((unsigned int) to_long(a)); }
inline void conv(unsigned int& x, double a) { x = ((unsigned int) to_long(a)); }

inline void conv(unsigned long& x, int a) { x = ((unsigned long)(a)); }
inline void conv(unsigned long& x, long a) { x = ((unsigned long)(a)); }
inline void conv(unsigned long& x, unsigned a) { x = ((unsigned long)(a)); }
inline void conv(unsigned long& x, unsigned long a) { x = a; }
inline void conv(unsigned long& x, float a) { x = ((unsigned int) to_long(a)); }
inline void conv(unsigned long& x, double a) { x = ((unsigned int) to_long(a)); }















long SkipWhiteSpace(NTL_SNS istream& s);
long IsWhiteSpace(long c);
long IsEOFChar(long c);

long CharToIntVal(long c);
char IntValToChar(long a);





inline double GetTime() { return _ntl_GetTime(); }
inline unsigned long GetPID() { return _ntl_GetPID(); }

inline double GetWallTime() { return _ntl_GetWallTime(); }

inline long IsFinite(double *p) { return _ntl_IsFinite(p); }


#if (NTL_EXT_DOUBLE)

inline void ForceToMem(double *p) { _ntl_ForceToMem(p); }

#else

inline void ForceToMem(double *p) { }

#endif


inline double TrueDouble(double x)
{
   ForceToMem(&x);
   return x;
}




void PrintTime(NTL_SNS ostream& s, double t);



#if (defined(__GNUC__) && (__GNUC__ >= 4))

// on relative modern versions of gcc, we can 
// decalare "restricted" pointers in C++

#define NTL_RESTRICT __restrict

#else

#define NTL_RESTRICT

#endif

// A very lightly wrapped pointer than does nothing more than provide
// auto cleanup in a destructor.  Use the UniquePtr class (in SmartPtr.h) 
// for a class with more safety and convenience features.
// This class is easiest to use to retrofit older code with RAII
// semantics.

// A call to Deleter::apply should free the pointed-to storage

template<class T, class Deleter>
class WrappedPtr {
private:
   WrappedPtr(const WrappedPtr&); // disable
   void operator=(const WrappedPtr&); // disable
public:
   typedef T * raw_ptr;

   raw_ptr rep;

   WrappedPtr() : rep(0) { }
   void operator=(const raw_ptr& _rep)  { rep = _rep; }

   ~WrappedPtr() { if (rep) Deleter::apply(rep); } 

   operator const raw_ptr& () const { return rep; }
   operator raw_ptr& () { return rep; }

   const raw_ptr* operator&() const { return &rep; }
   raw_ptr* operator&() { return &rep; }

   void kill() { if (rep) { Deleter::apply(rep); rep = 0; } }

   void swap(WrappedPtr& other) { _ntl_swap(rep, other.rep); }

   void move(WrappedPtr& other) 
   {
      WrappedPtr tmp;
      tmp.swap(other);
      tmp.swap(*this);
   }

};

template<class T, class Deleter>
void swap(WrappedPtr<T,Deleter>& x, WrappedPtr<T,Deleter>& y)
{
   x.swap(y);
}



// Error Handling



class ErrorObject : public NTL_SNS runtime_error {
public:
   ErrorObject(const char *msg) : runtime_error(msg) { }
};

class LogicErrorObject : public ErrorObject {
public: 
   LogicErrorObject(const char *msg) : ErrorObject(msg) { }
};

class ArithmeticErrorObject : public ErrorObject {
public: 
   ArithmeticErrorObject(const char *msg) : ErrorObject(msg) { }
};

class ResourceErrorObject : public ErrorObject {
public: 
   ResourceErrorObject(const char *msg) : ErrorObject(msg) { }
};

class FileErrorObject : public ErrorObject {
public: 
   FileErrorObject(const char *msg) : ErrorObject(msg) { }
};

class InputErrorObject : public ErrorObject {
public: 
   InputErrorObject(const char *msg) : ErrorObject(msg) { }
};



extern NTL_CHEAP_THREAD_LOCAL void (*ErrorCallback)();

extern NTL_CHEAP_THREAD_LOCAL void (*ErrorMsgCallback)(const char *);


void TerminalError(const char *s);

#ifdef NTL_EXCEPTIONS

inline void MemoryError() { throw NTL_SNS bad_alloc(); }
inline void Error(const char *msg) { throw ErrorObject(msg); }
inline void LogicError(const char *msg) { throw LogicErrorObject(msg); }
inline void ArithmeticError(const char *msg) { throw ArithmeticErrorObject(msg); }
inline void InvModError(const char *msg) { throw ArithmeticErrorObject(msg); }
inline void ResourceError(const char *msg) { throw ResourceErrorObject(msg); }
inline void FileError(const char *msg) { throw FileErrorObject(msg); }
inline void InputError(const char *msg) { throw InputErrorObject(msg); }

#else

inline void MemoryError() { TerminalError("out of memory"); }
inline void Error(const char *msg) { TerminalError(msg); }
inline void LogicError(const char *msg) { TerminalError(msg); }
inline void ArithmeticError(const char *msg) { TerminalError(msg); }
inline void InvModError(const char *msg) { TerminalError(msg); }
inline void ResourceError(const char *msg) { TerminalError(msg); }
inline void FileError(const char *msg) { TerminalError(msg); }
inline void InputError(const char *msg) { TerminalError(msg); }

#endif






#ifdef NTL_EXCEPTIONS


template < typename F  >
class scope_guard 
{
    typename std::remove_reference<F>::type f;
    bool active;
    const char *info;
    
public:
    scope_guard(F&& _f, const char *_info) : 
       f(std::forward<F>(_f)), active(true), info(_info) { }

    ~scope_guard() {
        if (active) {
#ifdef NTL_TEST_EXCEPTIONS
            NTL_SNS cerr << "*** ACTIVE SCOPE GUARD TRIGGERED: "
                         <<  info << "\n";
#endif
            f();
        }
    }

    void relax() { active = false; }
};


struct scope_guard_builder {  
   const char *info;
   explicit scope_guard_builder(const char *_info) : info(_info) { }
};

template < typename F >
scope_guard<F> 
operator+(scope_guard_builder b, F&& f)
{
    return scope_guard<F>(std::forward<F>(f), b.info);
}


#define NTL_SCOPE(var) auto var =  \
   scope_guard_builder(__FILE__ ":" NTL_STRINGIFY(__LINE__)) + [&]


#else


class DummyScopeGuard {
  bool active;
public:
   DummyScopeGuard() : active(true) { }
   ~DummyScopeGuard() { if (active) TerminalError("unexpected exception"); }
   
   void relax() { active = false; }
};

#define NTL_SCOPE(var) DummyScopeGuard var; if (false)




#endif





#if (defined(NTL_THREADS) && defined(NTL_TLS_HACK)) 

// NOTE: All of this TLS code is replicated in CheckThreads.cpp.


namespace details_pthread {


template<class T> void do_delete_aux(T* t) noexcept { delete t;  }
// an exception here would likely lead to a complete mess...
// the noexcept specification should force an immediate termination

template<class T> void do_delete(void* t) { do_delete_aux((T*)t);  }

using namespace std;
// I'm not sure if pthread stuff might be placed in namespace std

struct key_wrapper {
   pthread_key_t key;

   key_wrapper(void (*destructor)(void*))
   {
      if (pthread_key_create(&key, destructor))
         ResourceError("pthread_key_create failed");
   }

   template<class T>
   T* set(T *p)
   {
      if (!p) MemoryError();
      if (pthread_setspecific(key, p)) {
         do_delete_aux(p);
         ResourceError("pthread_setspecific failed");
      }
      return p;
   }

};

}


#define NTL_TLS_LOCAL_INIT(type, var, init)  \
   static NTL_CHEAP_THREAD_LOCAL type *_ntl_hidden_variable_tls_local_ptr_ ## var = 0;  \
   type *_ntl_hidden_variable_tls_local_ptr1_ ## var = _ntl_hidden_variable_tls_local_ptr_ ## var;  \
   if (!_ntl_hidden_variable_tls_local_ptr1_ ## var) {  \
      static details_pthread::key_wrapper hidden_variable_key(details_pthread::do_delete<type>);  \
      type *_ntl_hidden_variable_tls_local_ptr2_ ## var = hidden_variable_key.set(NTL_NEW_OP type init);  \
      _ntl_hidden_variable_tls_local_ptr1_ ## var = _ntl_hidden_variable_tls_local_ptr2_ ## var;  \
      _ntl_hidden_variable_tls_local_ptr_ ## var = _ntl_hidden_variable_tls_local_ptr1_ ## var;  \
   }  \
   type &var = *_ntl_hidden_variable_tls_local_ptr1_ ## var  \



#else


// NOTE: this definition of NTL_TLS_LOCAL_INIT ensures that var names
// a local reference, regardless of the implementation
#define NTL_TLS_LOCAL_INIT(type,var,init) \
    static NTL_THREAD_LOCAL type _ntl_hidden_variable_tls_local ## var init; \
    type &var = _ntl_hidden_variable_tls_local ## var




#endif

#define NTL_EMPTY_ARG
#define NTL_TLS_LOCAL(type,var) NTL_TLS_LOCAL_INIT(type,var,NTL_EMPTY_ARG)

#define NTL_TLS_GLOBAL_DECL_INIT(type,var,init)  \
   typedef type _ntl_hidden_typedef_tls_access_ ## var;  \
   static inline  \
   type& _ntl_hidden_function_tls_access_ ## var() {  \
      NTL_TLS_LOCAL_INIT(type,var,init);  \
      return var;  \
   }  \


#define NTL_TLS_GLOBAL_DECL(type,var) NTL_TLS_GLOBAL_DECL_INIT(type,var,NTL_EMPTY_ARG)

#define NTL_TLS_GLOBAL_ACCESS(var) \
_ntl_hidden_typedef_tls_access_ ## var & var = _ntl_hidden_function_tls_access_ ## var()


// **************************************************************
// Following is code for "long long" arithmetic that can
// be implemented using NTL_ULL_TYPE or using assembly.
// I have found that the assembly can be a bit faster.
// For now, this code is only available if NTL_HAVE_LL_TYPE
// is defined.  This could change.  In any case, this provides
// a cleaner interface and might eventually allow for 
// implementation on systems that don't provide a long long type.
// **************************************************************

#ifdef NTL_HAVE_LL_TYPE

      
#if (!defined(NTL_DISABLE_LL_ASM) \
     && defined(__GNUC__) && (__GNUC__ >= 4) && !defined(__INTEL_COMPILER)  && !defined(__clang__) \
     && defined (__x86_64__)  && NTL_BITS_PER_LONG == 64)

// NOTE: clang's and icc's inline asm code gen is pretty bad, so
// we don't even try. 

// FIXME: probably, this should all be properly tested for speed (and correctness)
// using the Wizard.


struct ll_type {
   unsigned long hi, lo;
};


inline void 
ll_mul_add(ll_type& x, unsigned long a, unsigned long b)
{
  unsigned long hi, lo;
   __asm__ (
   "mulq %[b] \n\t" 
   "addq %[lo],%[xlo] \n\t"
   "adcq %[hi],%[xhi]" : 
   [lo] "=a" (lo), [hi] "=d" (hi), [xhi] "+r" (x.hi), [xlo] "+r" (x.lo) : 
   [a] "%[lo]" (a), [b] "rm" (b) :
   "cc"
   );
}

inline void 
ll_imul_add(ll_type& x, unsigned long a, unsigned long b)
{
  unsigned long hi, lo;
   __asm__ (
   "imulq %[b] \n\t" 
   "addq %[lo],%[xlo] \n\t"
   "adcq %[hi],%[xhi]" : 
   [lo] "=a" (lo), [hi] "=d" (hi), [xhi] "+r" (x.hi), [xlo] "+r" (x.lo) : 
   [a] "%[lo]" (a), [b] "rm" (b) :
   "cc"
   );
}

inline void 
ll_mul(ll_type& x, unsigned long a, unsigned long b)
{
   __asm__ (
   "mulq %[b]" :
   [lo] "=a" (x.lo), [hi] "=d" (x.hi) : 
   [a] "%[lo]" (a), [b] "rm" (b) :
   "cc"
   );
}

inline void 
ll_imul(ll_type& x, unsigned long a, unsigned long b)
{
   __asm__ (
   "imulq %[b]" :
   [lo] "=a" (x.lo), [hi] "=d" (x.hi) : 
   [a] "%[lo]" (a), [b] "rm" (b) :
   "cc"
   );
}

inline void
ll_add(ll_type& x, unsigned long a)
{
   __asm__ (
   "addq %[a],%[xlo] \n\t"
   "adcq %[z],%[xhi]" :
   [xhi] "+r" (x.hi), [xlo] "+r" (x.lo) :
   [a] "rm" (a), [z] "i" (0) :
   "cc"
   );
}



// NOTE: an optimizing compiler will remove the conditional.
// The alternative would be to make a specialization for shamt=0.
// Unfortunately, this is impossible to do across a wide range
// of compilers and still maintain internal linkage --- it is not 
// allowed to include static spec in the specialization (new compilers
// will complain) and without it, some older compilers will generate
// an external symbol.  In fact, NTL currently never calls 
// this with shamt=0, so it is all rather academic...but I want to
// keep this general for future use.

// NOTE: this implementation assumes that shamt is in the range 
// 0..NTL_BITS_PER_LONG-1

#if 1

// The shrd instruction can be very slow on some
// machines.  Two shifts is usually just as good.

template<long shamt>
unsigned long
ll_rshift_get_lo(ll_type x)
{
   unsigned long res;
   if (shamt) 
      res = (x.lo >> shamt) | (x.hi << (NTL_BITS_PER_LONG-shamt));
   else
      res = x.lo;
      
   return res;
}

#else


template<long shamt>
unsigned long
ll_rshift_get_lo(ll_type x)
{
   if (shamt) {
      __asm__ (
      "shrdq %[shamt],%[hi],%[lo]" :
      [lo] "+r" (x.lo) : 
      [shamt] "i" (shamt), [hi] "r" (x.hi) :
      "cc"
      );
   }
   return x.lo;
}

#endif


inline unsigned long 
ll_get_lo(const ll_type& x)
{
   return x.lo;
}

inline unsigned long 
ll_get_hi(const ll_type& x)
{
   return x.hi;
}


inline void
ll_init(ll_type& x, unsigned long a)
{
   x.lo = a;
   x.hi = 0;
}

#else


typedef NTL_ULL_TYPE ll_type;

// NOTE: the following functions definitions should serve as
// documentation, as well.

inline void 
ll_mul_add(ll_type& x, unsigned long a, unsigned long b)
{
   x += ((ll_type) a)*((ll_type) b);
}

// a and b should be representable as positive long's,
// to allow for the most flexible implementation
inline void 
ll_imul_add(ll_type& x, unsigned long a, unsigned long b)
{
   x += ((ll_type) long(a))*((ll_type) long(b));
}
inline void 
ll_mul(ll_type& x, unsigned long a, unsigned long b)
{
   x = ((ll_type) a)*((ll_type) b);
}

// a and b should be representable as positive long's,
// to allow for the most flexible implementation
inline void 
ll_imul(ll_type& x, unsigned long a, unsigned long b)
{
   x = ((ll_type) long(a))*((ll_type) long(b));
}

inline void
ll_add(ll_type& x, unsigned long a)
{
   x += a;
}

// NOTE: shamt must be in the range 0..NTL_BITS_PER_LONG-1
template<long shamt>
unsigned long
ll_rshift_get_lo(const ll_type& x)
{
   return ((unsigned long) (x >> shamt));
}

inline unsigned long 
ll_get_lo(const ll_type& x)
{
   return ((unsigned long) x);
}

inline unsigned long 
ll_get_hi(const ll_type& x)
{
   return ((unsigned long) (x >> NTL_BITS_PER_LONG));
}


inline void
ll_init(ll_type& x, unsigned long a)
{
   x = a;
}


#endif


inline unsigned long 
ll_mul_hi(unsigned long a, unsigned long b)
{
   ll_type x;
   ll_mul(x, a, b);
   return ll_get_hi(x);
} 


#endif





#ifdef NTL_SAFE_VECTORS


#define NTL_RELOC_TAG (relocatable)

#define NTL_DECLARE_RELOCATABLE_WHEN(x) \
constexpr bool DeclareRelocatableType x

#if (defined(NTL_HAVE_COPY_TRAITS1) || defined(_MSC_VER))


// This strategy is used on compilers that fully support C++11 type traits.
// For some reason, is_trivially_copyable says "true" even if the class
// has deleted it's copy constructor.  Which means it is not copyable at all.
// So I added an explicit test for is_copy_constructible.
// Just to be on the safe side, I check for a trivial destructor.

// This strategy is checked in the CheckCOPY_TRAITS1.cpp program.


template<class T>
constexpr bool Relocate_aux_has_trivial_copy(T*)
{
   return  std::is_trivially_copyable<T>::value &&
           std::is_trivially_destructible<T>::value &&
           std::is_copy_constructible<T>::value;
}

template<class T>
constexpr bool Relocate_aux_has_any_copy(T*)
{
   return std::is_copy_constructible<T>::value;
}

#elif (defined(NTL_HAVE_COPY_TRAITS2))

// This strategy is needed on GCC before v5.0, as the required type
// traits are not impplemented.  Note that on a class with it's copy
// constructors deleted, __has_trivial_copy is false on GCC before 4.9
// and true startig with 4.9.  So I had to make use of SFINAE techniques
// to make sure there actually is a non-deleted copy constructor.
// Just to be on the safe side, I check for a trivial destructor.

// This strategy is checked in the CheckCOPY_TRAITS1.cpp program.

template <bool statement, typename out>
struct Relocate_aux_Failable
{
     typedef out Type;
};

struct Relocate_aux_TwoChars { char d[2]; };

template <typename T>
struct Relocate_aux_has_copy
{

     static const T *MakeT();

     template <typename U> // U and T are the same type
     static typename Relocate_aux_Failable<(bool(sizeof U(*MakeT()))), char>::Type copy(int);

     template <typename U>
     static typename Relocate_aux_Failable<true, Relocate_aux_TwoChars>::Type copy(...);

     enum { value =  sizeof( copy<T>(0) )  == 1 };
};


template<class T>
constexpr bool Relocate_aux_has_trivial_copy(T*)
{
   return  __has_trivial_copy(T) &&
           __has_trivial_destructor(T) &&
           Relocate_aux_has_copy<T>::value;
}

template<class T>
constexpr bool Relocate_aux_has_any_copy(T*)
{
   return Relocate_aux_has_copy<T>::value;
}


#else

#error "lacking compiler support for NTL_SAFE_VECTORS"

#endif


// NOTE: I've checked the correctness of the above strategies using
// Godbolt's compiler explorer across a range of complilers
// (clang, gcc, icc, MS).


template<class T>
constexpr bool DeclareRelocatableType(T*)
{
   return Relocate_aux_has_trivial_copy((T*)0);
}
 

#else

#define NTL_RELOC_TAG (true)

#define NTL_DECLARE_RELOCATABLE_WHEN(x) \
inline bool DeclareRelocatableType x


template<class T>
inline bool DeclareRelocatableType(T*)
{
   return true;
}

#endif


#define NTL_DECLARE_RELOCATABLE(x) NTL_DECLARE_RELOCATABLE_WHEN(x) \
   { return true; }


// Examples: 
//   NTL_DECLARE_RELOCATABLE((int*))
//   NTL_DECLARE_RELOCATABLE((Foo<int>*)) 
//   template <class X, class Y> NTL_DECLARE_RELOCATABLE((Foo<X,Y>*))


#if (NTL_CXX_STANDARD >= 2011)

#define NTL_DEFAULT =default;

#else

#define NTL_DEFAULT {}

#endif


// The following idea for deriving from streambuf comes from:
// https://stackoverflow.com/questions/1448467/initializing-a-c-stdistringstream-from-an-in-memory-buffer/1449527#1449527

struct plain_c_string_streambuf : public std::streambuf
{
   plain_c_string_streambuf(const char* ss)
   {
      char *s = const_cast<char*>(ss);
      // casting away constant should be safe here,
      // based of my reading of the functionality
      // of streambuf from the documentation at cplusplus.com.
    
      setg(s, s, s + std::strlen(s));
   }
};

// Generic conversion from char* or const char*.  We use SFINAE
// to prevent conversions from 0. 


template<class S, class T>
typename _ntl_enable_if<_ntl_is_char_pointer<T>::value,void>::type
conv(S& x, T y)
{
   if (!y) InputError("bad conversion from char*");
   plain_c_string_streambuf buf(y);
   std::istream istr(&buf);
   if (!(istr >> x)) InputError("bad conversion from char*");
}



// new style converson function
//   example: ZZ x = conv<ZZ>(1);
//   note: modern C++ compilers should implemented 
//     "named return value optimization", so the
//     result statement should not create a temporary

template<class T, class S>
T conv(const S& a)
{
   T x;
   conv(x, a);
   return x;
}



NTL_CLOSE_NNS


#endif

