x86_64.hpp

// -*-C++-*-

#ifndef X86_64_ARCH_HPP
#define X86_64_ARCH_HPP

#define ARCH_x86

namespace os {

  // Concept / base class Arch
  struct Arch {
    static constexpr uintptr_t   max_canonical_addr = 0xffffffffffff;
    static constexpr uint8_t     word_size          = sizeof(uintptr_t) * 8;
    static constexpr uintptr_t   min_page_size      = 4096;
    static constexpr const char* name               = "x86_64";

    static inline uint64_t cpu_cycles() noexcept;
    static inline void read_memory_barrier() noexcept;
    static inline void write_memory_barrier() noexcept;
  };

}

// Implementation
uint64_t os::Arch::cpu_cycles() noexcept {
  uint32_t hi, lo;
  asm("rdtsc" : "=a"(lo), "=d"(hi));
  return ((uint64_t) lo) | ((uint64_t) hi) << 32;
}

inline void os::Arch::read_memory_barrier() noexcept {
  __asm volatile("lfence" ::: "memory");
}

inline void os::Arch::write_memory_barrier() noexcept {
  __asm volatile("mfence" ::: "memory");
}

#endif