// sse_simd.cpp - written and placed in the public domain by

//                Jeffrey Walton, Uri Blumenthal and Marcel Raad.

//

//    This source file uses intrinsics to gain access to SSE for CPU

//    feature testing. A separate source file is needed because additional

//    CXXFLAGS are required to enable the appropriate instructions set in

//    some build configurations.

#include "pch.h"

#include "config.h"

#include "cpu.h"

// Needed by MIPS for definition of NULL

#include "stdcpp.h"

#ifdef CRYPTOPP_GNU_STYLE_INLINE_ASSEMBLY

# include <signal.h>

# include <setjmp.h>

#endif

#ifndef EXCEPTION_EXECUTE_HANDLER

# define EXCEPTION_EXECUTE_HANDLER 1

#endif

// Needed by SunCC and MSVC

#if (CRYPTOPP_BOOL_X86 || CRYPTOPP_BOOL_X32 || CRYPTOPP_BOOL_X64)

# if !defined(CRYPTOPP_NO_CPU_FEATURE_PROBES) && !CRYPTOPP_SSE2_ASM_AVAILABLE && CRYPTOPP_SSE2_INTRIN_AVAILABLE

#  include <emmintrin.h>

# endif

#endif

// Squash MS LNK4221 and libtool warnings

extern const char SSE_SIMD_FNAME[] = __FILE__;

NAMESPACE_BEGIN(CryptoPP)

#ifdef CRYPTOPP_GNU_STYLE_INLINE_ASSEMBLY

extern "C" {

    typedef void (*SigHandler)(int);

}

extern "C"

{

    static jmp_buf s_jmpNoSSE2;

    static void SigIllHandler(int)

    {

        longjmp(s_jmpNoSSE2, 1);

    }

}

#endif  // CRYPTOPP_GNU_STYLE_INLINE_ASSEMBLY

bool CPU_ProbeSSE2()

{

    // Apple switched to Intel desktops in 2005/2006 using

    //   Core2 Duo's, which provides SSE2 and above.

#if CRYPTOPP_BOOL_X64 || defined(__APPLE__)

    return true;

#elif defined(CRYPTOPP_NO_CPU_FEATURE_PROBES)

    return false;

#elif defined(CRYPTOPP_MS_STYLE_INLINE_ASSEMBLY)

    __try

    {

# if CRYPTOPP_SSE2_ASM_AVAILABLE

        AS2(por xmm0, xmm0)        // executing SSE2 instruction

# elif CRYPTOPP_SSE2_INTRIN_AVAILABLE

        __m128i x = _mm_setzero_si128();

        return _mm_cvtsi128_si32(x) == 0;

# endif

    }

    // GetExceptionCode() == EXCEPTION_ILLEGAL_INSTRUCTION

    __except (EXCEPTION_EXECUTE_HANDLER)

    {

        return false;

    }

    return true;

#else

    // longjmp and clobber warnings. Volatile is required.

    // http://github.com/weidai11/cryptopp/issues/24 and http://stackoverflow.com/q/7721854

    volatile bool result = true;

    volatile SigHandler oldHandler = signal(SIGILL, SigIllHandler);

    if (oldHandler == SIG_ERR)

        return false;

# ifndef __MINGW32__

    volatile sigset_t oldMask;

    if (sigprocmask(0, NULLPTR, (sigset_t*)&oldMask))

    {

        signal(SIGILL, oldHandler);

        return false;

    }

# endif

    if (setjmp(s_jmpNoSSE2))

        result = false;

    else

    {

# if CRYPTOPP_SSE2_ASM_AVAILABLE

        __asm __volatile ("por %xmm0, %xmm0");

# elif CRYPTOPP_SSE2_INTRIN_AVAILABLE

        __m128i x = _mm_setzero_si128();

        result = _mm_cvtsi128_si32(x) == 0;

# endif

    }

# ifndef __MINGW32__

    sigprocmask(SIG_SETMASK, (sigset_t*)&oldMask, NULLPTR);

# endif

    signal(SIGILL, oldHandler);

    return result;

#endif

}

NAMESPACE_END