Visual Studio 인라인 어셈블리 x86 예제

• power

#include <stdio.h>

int power2( int num, int power );

int main( void )
{
    printf_s( "3 times 2 to the power of 5 is %d\n", \
              power2( 3, 5) );
}
int power2( int num, int power )
{
   __asm
   {
      mov eax, num    ; Get first argument
      mov ecx, power  ; Get second argument
      shl eax, cl     ; EAX = EAX * ( 2 to the power of CL )
   }
   // Return with result in EAX
}

docs.microsoft.com/ko-kr/cpp/assembler/inline/writing-functions-with-inline-assembly?view=vs-2019

 

 

• 레이블로 점프

void func( void )
{
   goto C_Dest;  /* Legal: correct case   */
   goto c_dest;  /* Error: incorrect case */

   goto A_Dest;  /* Legal: correct case   */
   goto a_dest;  /* Legal: incorrect case */

   __asm
   {
      jmp C_Dest ; Legal: correct case
      jmp c_dest ; Legal: incorrect case

      jmp A_Dest ; Legal: correct case
      jmp a_dest ; Legal: incorrect case

      a_dest:    ; __asm label
   }

   C_Dest:       /* C label */
   return;
}
int main()
{
}

docs.microsoft.com/ko-kr/cpp/assembler/inline/jumping-to-labels-in-inline-assembly?view=vs-2019

 

• C함수 호출

// InlineAssembler_Calling_C_Functions_in_Inline_Assembly.cpp
// processor: x86
#include <stdio.h>

char format[] = "%s %s\n";
char hello[] = "Hello";
char world[] = "world";
int main( void )
{
   __asm
   {
      mov  eax, offset world
      push eax
      mov  eax, offset hello
      push eax
      mov  eax, offset format
      push eax
      call printf
      //clean up the stack so that main can exit cleanly
      //use the unused register ebx to do the cleanup
      pop  ebx
      pop  ebx
      pop  ebx
   }
}

docs.microsoft.com/ko-kr/cpp/assembler/inline/calling-c-functions-in-inline-assembly?view=vs-2019