Check SSE/AVX instruction support.

ssecheck.cpp

/*
	Check SSE/AVX support.
	This application can detect the instruction support of
	SSE, SSE2, SSE3, SSSE3, SSE4.1, SSE4.2, SSE4a, SSE5, and AVX.
*/

#include <iostream>
#ifdef _MSC_VER
#include <intrin.h>
#endif

#ifdef __GNUC__

void __cpuid(int* cpuinfo, int info)
{
	__asm__ __volatile__(
		"xchg %%ebx, %%edi;"
		"cpuid;"
		"xchg %%ebx, %%edi;"
		:"=a" (cpuinfo[0]), "=D" (cpuinfo[1]), "=c" (cpuinfo[2]), "=d" (cpuinfo[3])
		:"0" (info)
	);
}

unsigned long long _xgetbv(unsigned int index)
{
	unsigned int eax, edx;
	__asm__ __volatile__(
		"xgetbv;"
		: "=a" (eax), "=d"(edx)
		: "c" (index)
	);
	return ((unsigned long long)edx << 32) | eax;
}

#endif

int main()
{
	bool sseSupportted = false;
	bool sse2Supportted = false;
	bool sse3Supportted = false;
	bool ssse3Supportted = false;
	bool sse4_1Supportted = false;
	bool sse4_2Supportted = false;
	bool sse4aSupportted = false;
	bool sse5Supportted = false;
	bool avxSupportted = false;

	int cpuinfo[4];
	__cpuid(cpuinfo, 1);

	// Check SSE, SSE2, SSE3, SSSE3, SSE4.1, and SSE4.2 support
	sseSupportted		= cpuinfo[3] & (1 << 25) || false;
	sse2Supportted		= cpuinfo[3] & (1 << 26) || false;
	sse3Supportted		= cpuinfo[2] & (1 << 0) || false;
	ssse3Supportted		= cpuinfo[2] & (1 << 9) || false;
	sse4_1Supportted	= cpuinfo[2] & (1 << 19) || false;
	sse4_2Supportted	= cpuinfo[2] & (1 << 20) || false;
	
	// ----------------------------------------------------------------------

	// Check AVX support
	// References
	// http://software.intel.com/en-us/blogs/2011/04/14/is-avx-enabled/
	// http://insufficientlycomplicated.wordpress.com/2011/11/07/detecting-intel-advanced-vector-extensions-avx-in-visual-studio/
	
	avxSupportted = cpuinfo[2] & (1 << 28) || false;
	bool osxsaveSupported = cpuinfo[2] & (1 << 27) || false;
	if (osxsaveSupported && avxSupportted)
	{
		// _XCR_XFEATURE_ENABLED_MASK = 0
		unsigned long long xcrFeatureMask = _xgetbv(0);
		avxSupportted = (xcrFeatureMask & 0x6) == 0x6;
	}

	// ----------------------------------------------------------------------

	// Check SSE4a and SSE5 support

	// Get the number of valid extended IDs
	__cpuid(cpuinfo, 0x80000000);
	int numExtendedIds = cpuinfo[0];
	if (numExtendedIds >= 0x80000001)
	{
		__cpuid(cpuinfo, 0x80000001);
		sse4aSupportted = cpuinfo[2] & (1 << 6) || false;
		sse5Supportted = cpuinfo[2] & (1 << 11) || false;
	}

	// ----------------------------------------------------------------------

	std::cout << "SSE:" << (sseSupportted ? 1 : 0) << std::endl;
	std::cout << "SSE2:" << (sse2Supportted ? 1 : 0) << std::endl;
	std::cout << "SSE3:" << (sse3Supportted ? 1 : 0) << std::endl;
	std::cout << "SSE4.1:" << (sse4_1Supportted ? 1 : 0) << std::endl;
	std::cout << "SSE4.2:" << (sse4_2Supportted ? 1 : 0) << std::endl;
	std::cout << "SSE4a:" << (sse4aSupportted ? 1 : 0) << std::endl;
	std::cout << "SSE5:" << (sse5Supportted ? 1 : 0) << std::endl;
	std::cout << "AVX:" << (avxSupportted ? 1 : 0) << std::endl;

	return 0;
}

The ssse3Supportted are not displayed after assigning its value. You declared 9 variables but there are only 8 results.

sse3 and ssse3 are not same.