arch/x86_64/src/kernel/cpu/gdtr.cpp


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#include "arch/kernel/cpu/gdtr.hpp"

#include "arch/context_switching/segment_descriptor_table/global_descriptor_table_pointer.hpp"

namespace teachos::arch::kernel::cpu
{
  auto store_global_descriptor_table() -> context_switching::segment_descriptor_table::global_descriptor_table_pointer
  {
    context_switching::segment_descriptor_table::global_descriptor_table_pointer current_value{};
    asm("sgdt %[output]" : [output] "=m"(current_value));
    return current_value;
  }

  auto load_global_descriptor_table(
      context_switching::segment_descriptor_table::global_descriptor_table_pointer const & gdt_pointer) -> void
  {
    asm volatile("lgdt %[input]" : /* no output from call */ : [input] "m"(gdt_pointer));
  }
}  // namespace teachos::arch::kernel::cpu