//-------------------------------------------------------------------
//	trybswap.cpp
//
//	This is the code we wrote quickly during class to answer the
//	question, asked by Zahara Docena, about whether 'bswap' will
//	operate as we expect when it's used with a 64-bit register.  
//	Of course we could have looked up the 'bswap' instruction in 
//	Volume 2A of the Intel Software Developer's Manual (online),
//	but this was a good opportunity to employ 'inline' assembly 
//	language within a 'high-level' programming language example.
//
//		to compile:  $ g++ trybswap.cpp -o trybswap
//		to execute:  $ ./trybswap
//
//	programmer: ALLAN CRUSE
//	written on: 20 APR 2009
//-------------------------------------------------------------------

#include <stdio.h>	// for printf()  

unsigned long long	x;

int main( int argc, char **argv )
{
	x = 0x0123456789ABCDEF;

	printf( "\n x = %016llX \n", x );

	asm(" mov  x, %rax ");
	asm(" bswap %rax ");
	asm(" mov %rax, x ");

	printf( "\n x = %016llX \n", x );
}