Few tricks that I found out when I had a look at the segment registers in Windows.

detectArch.c

#include <Windows.h>
#include <wchar.h>

/*
 * Author: Osanda Malith Jayathissa - @OsandaMalith
 * Website: https://osandamalith.com
 * Description: Few tricks that you can use to detect the architecture in Windows
 * Link :  http://osandamalith.com/2017/09/24/detecting-architecture-in-windows/ 
 */

BOOL detectArch_ES() {
#if defined(_MSC_VER)
	_asm {
		xor eax, eax
		mov ax, es
		ror ax, 0x3
		and eax, 0x1			
	}
#elif defined(__GNUC__)		
asm(  
		".intel_syntax noprefix;"
		"xor eax, eax;"
		"mov ax, es;"
		"ror ax, 0x3;"
		"and eax, 0x1;"
			
	);
#endif
}

BOOL detectArch_GS() {
#if defined(_MSC_VER)
	_asm {
		xor eax, eax
		mov ax, gs

	}
#elif defined(__GNUC__)		
	asm(
		".intel_syntax noprefix;"
		"xor eax, eax;"
		"mov ax, gs;"
		);
#endif
}

BOOL detectArch_TEB() {
#if defined(_MSC_VER)
	_asm {
		xor eax, eax
		mov eax, fs:[0xc0]

	}
#elif defined(__GNUC__)		
	asm(
		".intel_syntax noprefix;"
		"xor eax, eax;"
		"mov eax, fs:[0xc0];"
		);
#endif
}

int main(int argc, char* argv[]) {
	wprintf(
		!detectArch_ES() ? 
		L"You are Running 32-bit\n" :
		L"You are Running 64-bit\n"
		);

	
	wprintf(
		!detectArch_GS() ?
		L"You are Running 32-bit\n" :
		L"You are Running 64-bit\n"
		);
		
	wprintf(
		!detectArch_TEB() ?
		L"You are Running 32-bit\n" :
		L"You are Running 64-bit\n"
		);
		
	return 1337;
}