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#ifndef RDPSCP_H
#define RDPSCP_H
// performance test
#if !defined(__arm__) && !defined(__aarch64__) && !defined(__powerpc64__) && !defined(__PPC64__) && \
!defined(__powerpc__) && !defined(__riscv)
#include <x86intrin.h>
#include <cpuid.h>
#ifdef __clang__
bool has_rdtscp() { return true; }
/** CPU cycles since processor startup */
inline uint64_t rdtsc() {
uint32_t lo, hi;
/* We cannot use "=A", since this would use %rax on x86_64 */
__asm__ __volatile__("rdtsc" : "=a"(lo), "=d"(hi));
return (uint64_t)hi << 32 | lo;
}
#else
// CPUID, EAX = 0x80000001, EDX values
#ifndef bit_RDTSCP
#define bit_RDTSCP (1 << 27)
#endif
namespace {
inline bool has_rdtscp() {
unsigned int eax, ebx, ecx, edx;
if (__get_cpuid(0x80000001, &eax, &ebx, &ecx, &edx))
return (edx & bit_RDTSCP) != 0;
else
return false;
}
unsigned int rdtscp_val = 0;
inline unsigned long long rdtsc() { return __rdtscp(&rdtscp_val); }
} // namespace
#endif
#else // !defined(__arm__) && !defined(__aarch64__)
namespace {
inline bool has_rdtscp() { return false; }
inline unsigned long long rdtsc() { return 0; }
} // namespace
#endif // !defined(__arm__) && !defined(__aarch64__)
#endif
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