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#pragma once

#include <util/generic/typelist.h>
#include <util/system/cpu_id.h>
#include <util/system/defaults.h>
#include <util/system/hi_lo.h>
#include <util/system/platform.h>

#if defined(_MSC_VER) 
#include <intrin.h> 
#endif

static inline ui32 PopCountImpl(ui8 n) { 
#if defined(_ppc64_)
    ui32 r;
    __asm__("popcntb %0, %1"
            : "=r"(r)
            : "r"(n)
            :);
    return r;
#else
    extern ui8 const* PopCountLUT8; 
    return PopCountLUT8[n]; 
#endif
} 

static inline ui32 PopCountImpl(ui16 n) { 
#if defined(_MSC_VER) 
    return __popcnt16(n); 
#else
    extern ui8 const* PopCountLUT16; 
    return PopCountLUT16[n]; 
#endif
} 

static inline ui32 PopCountImpl(ui32 n) { 
#if defined(_MSC_VER) 
    return __popcnt(n); 
#else
#if defined(_x86_64_) 
    if (NX86::CachedHavePOPCNT()) {
        ui32 r; 
 
        __asm__("popcnt %1, %0;" 
                : "=r"(r) 
                : "r"(n) 
                :); 
 
        return r; 
    } 
#else
#if defined(_ppc64_)
    ui32 r;

    __asm__("popcntw %0, %1"
            : "=r"(r)
            : "r"(n)
            :);

    return r;
#endif 
#endif
 
    return PopCountImpl((ui16)Lo16(n)) + PopCountImpl((ui16)Hi16(n));
#endif
} 

static inline ui32 PopCountImpl(ui64 n) { 
#if defined(_MSC_VER) && !defined(_i386_)
    return __popcnt64(n); 
#else
#if defined(_x86_64_) 
    if (NX86::CachedHavePOPCNT()) {
        ui64 r; 
 
        __asm__("popcnt %1, %0;" 
                : "=r"(r) 
                : "r"(n) 
                :); 
 
        return r; 
    } 
#else
#if defined(_ppc64_)
    ui32 r;

    __asm__("popcntd %0, %1"
            : "=r"(r)
            : "r"(n)
            :);

    return r;
#endif 
#endif
 
    return PopCountImpl((ui32)Lo32(n)) + PopCountImpl((ui32)Hi32(n));
#endif
} 

template <class T> 
static inline ui32 PopCount(T n) { 
    using TCvt = TFixedWidthUnsignedInt<T>;

    return PopCountImpl((TCvt)n); 
}