tsc.hpp

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#ifndef TSC_HPP
#define TSC_HPP

#include <intrin.h>
#include <stdint.h>

#define BASE_FREQUENCY  100000000       
inline unsigned __int64 PLAT_rdtsc()
{
    return __rdtsc();
}

inline uint64_t getTSCFrequency( unsigned millis ) {
    UINT16 multiplierx2;
    uint64_t frequency = 0;
    DWORD mhz;
    DWORD mhz_sz = sizeof(mhz);

    if( RegGetValue( HKEY_LOCAL_MACHINE, "HARDWARE\\DESCRIPTION\\System\\CentralProcessor\\0", "~MHz", RRF_RT_REG_DWORD, NULL, &mhz, &mhz_sz ) != ERROR_SUCCESS ) {
        goto done;
    }
    fprintf( stderr, "mhz: %u\n", mhz );
    multiplierx2 = (UINT16)((2*mhz*1000000ULL)/BASE_FREQUENCY);
    if( multiplierx2 % 2 == 1 ) ++multiplierx2;
    fprintf( stderr, "Multiplier: %hhu\n", multiplierx2/2 );

    frequency = (((uint64_t)multiplierx2)*BASE_FREQUENCY)/2;
    fprintf( stderr, "Frequency: %llu\n", frequency );

done:
    return frequency;
}

#endif/*TSC_HPP*/