PspSetContext Anti-Tracing Trick

//When debuggers call ZwSetContextThread upon its debuggee, the "nt!PspSetContext" function is called, which
//filters certain EFlags out of the _CONTEXT structure e.g. Alignment Check. This can be used as
//an Anti-Tracing Trick (also Anti-Debug). Tested on Windows 7 SP1 (64-Bit).
//Credit: @nickeverdox
//Description: http://everdox.blogspot.com/2013/03/2-anti-tracing-mechanisms-specific-to.html

#include "stdafx.h"
#include "windows.h"
#include "stdio.h"

int main(int argc, char* argv[])
{
    unsigned long xXx = 1 << 18; //Alignment Check of EFlags
    __asm
    {
        pushfd
        mov ecx,xXx
        or dword ptr[esp],ecx
        popfd
    }

    //if the flag is lost, then code is being traced
    //printf("%s\r\n","Hope you are not tracing it?!!");
    unsigned long EFlags = 0;
    __asm
    {
        pushfd
        pop ecx
        mov EFlags,ecx
    }

    if( (EFlags&xXx) == 0)  MessageBox(0,"Being traced!!!","waliedassar",0);
    else    MessageBox(0,"Expected","waliedassar",0);
    ExitProcess(0);
    return 0;
}