How to: Inline assembler in C++ (under Visual Studio 2010)

Question

I\'m writing a performance-critical, number-crunching C++ project where 70% of the time is used by the 200 line core module.

I\'d like to optimize the core using inl

Answer 1

You can access variables by their name and copy them to registers. Here's an example from MSDN:

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
}

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