CxxUtils::detail Namespace Reference

Portable implementations. More...

Classes
struct	CHMTableIterator
	Helper to generate hash probes. More...
class	ConcurrentHashmapImpl
	Hash table allowing concurrent, lockless reads. More...
class	HashmapLock
	Helper to allow for external locking with put(). More...
struct	SizedUInt
struct	SizedUInt< 1 >
struct	SizedUInt< 2 >
struct	SizedUInt< 4 >
struct	SizedUInt< 8 >
union	UIntConv
	Helpers for converting between uintptr_t and a pointer or integer. More...
union	UIntConv< uintptr_t >

Typedefs
using	ConcurrentHashmapVal_t = uintptr_t
	Type used for keys and values — an unsigned big enough to hold a pointer. More...

Functions
template<typename T >
constexpr unsigned	ctz_portable (T x)
template<typename T >
constexpr unsigned	clz_portable (T x)
template<typename T >
constexpr unsigned	popcount_portable (T x)

Detailed Description

Portable implementations.

These could be replaced by faster algorithms if needed

Typedef Documentation

ConcurrentHashmapVal_t

using CxxUtils::detail::ConcurrentHashmapVal_t = typedef uintptr_t

Type used for keys and values — an unsigned big enough to hold a pointer.

Need to have this defined outside of ConcurrentHashmapImpl itself in order to avoid instantiation circularities, as the HASHER_ and MATCHER_ classes will probably want to use it.

Definition at line 41 of file ConcurrentHashmapImpl.h.

Function Documentation

clz_portable()

template<typename T >

constexpr unsigned CxxUtils::detail::clz_portable ( T  x )

inlineconstexpr

Definition at line 45 of file bitscan.h.

                                                {
      static_assert(std::is_integral<T>::value, "An integer type is required.");
      if (x==0) return sizeof(T)*8;
      unsigned n(0);
      T msb = static_cast<T>(1) << (sizeof(T)*8-1);
      for (n = 0; (x & msb) == 0; ++n, x <<= 1);
      return n;
    }    

ctz_portable()

template<typename T >

constexpr unsigned CxxUtils::detail::ctz_portable ( T  x )

inlineconstexpr

Definition at line 35 of file bitscan.h.

                                                {
      static_assert(std::is_integral<T>::value, "An integer type is required.");
      unsigned n(0);
      if (x!=0) {
        for (;(x & 0x1) == 0; ++n, x >>= 1);
      }
      return n;
    }    

popcount_portable()

template<typename T >

constexpr unsigned CxxUtils::detail::popcount_portable ( T  x )

inlineconstexpr

Definition at line 55 of file bitscan.h.

                                                     {
      static_assert(std::is_integral<T>::value, "An integer type is required.");
      unsigned n = 0;
      while (x != 0) {
        n += (x&1);
        x >>= 1;
      }
      return n;
    }