/*

   BLIS
   An object-based framework for developing high-performance BLAS-like
   libraries.

   Copyright (C) 2014, The University of Texas at Austin
   Copyright (C) 2018-2020, Advanced Micro Devices, Inc.
   Copyright (C) 2019, Dave Love, University of Manchester

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions are
   met:
    - Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
    - Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.
    - Neither the name(s) of the copyright holder(s) nor the names of its
      contributors may be used to endorse or promote products derived
      from this software without specific prior written permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*/

#if 0
  // Used only during standalone testing of ARM support.
  #include "bli_system.h"
  #include "bli_type_defs.h"
  #include "bli_cpuid.h"
  #undef __x86_64__
  #undef _M_X64
  #undef __i386
  #undef _M_IX86
  #define __arm__
#endif

#ifdef BLIS_CONFIGURETIME_CPUID

  // NOTE: If you need to make any changes to this cpp branch, it's probably
  // the case that you also need to modify bli_arch.c, bli_cpuid.c, and
  // bli_env.c. Don't forget to update these other files as needed!

  // The BLIS_ENABLE_SYSTEM macro must be defined so that the correct cpp
  // branch in bli_system.h is processed. (This macro is normally defined in
  // bli_config.h.)
  #define BLIS_ENABLE_SYSTEM

  // Use C-style static inline functions for any static inline functions that
  // happen to be defined by the headers below. (This macro is normally defined
  // in bli_config_macro_defs.h.)
  #define BLIS_INLINE static

  // Since we're not building a shared library, we can forgo the use of the
  // BLIS_EXPORT_BLIS annotations by #defining them to be nothing. (This macro
  // is normally defined in bli_config_macro_defs.h.)
  #define BLIS_EXPORT_BLIS

  #include "bli_system.h"
  #include "bli_type_defs.h"
  #include "bli_arch.h"
  #include "bli_cpuid.h"
  //#include "bli_env.h"
#else
  #include "blis.h"
#endif

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

#if defined(__x86_64__) || defined(_M_X64) || defined(__i386) || defined(_M_IX86)

#include "cpuid.h"

arch_t bli_cpuid_query_id( void )
{
	uint32_t vendor, family, model, features;

	// Call the CPUID instruction and parse its results into a family id,
	// model id, and a feature bit field. The return value encodes the
	// vendor.
	vendor = bli_cpuid_query( &family, &model, &features );

#if 0
	printf( "vendor   = %s\n", vendor==1 ? "AMD": "INTEL" );
	printf("family    = %x\n", family );
	printf( "model    = %x\n", model );

	printf( "features = %x\n", features );
#endif

	if ( vendor == VENDOR_INTEL )
	{
		// Check for each Intel configuration that is enabled, check for that
		// microarchitecture. We check from most recent to most dated.
#ifdef BLIS_CONFIG_SKX
		if ( bli_cpuid_is_skx( family, model, features ) )
			return BLIS_ARCH_SKX;
#endif
#ifdef BLIS_CONFIG_KNL
		if ( bli_cpuid_is_knl( family, model, features ) )
			return BLIS_ARCH_KNL;
#endif
#ifdef BLIS_CONFIG_HASWELL
		if ( bli_cpuid_is_haswell( family, model, features ) )
			return BLIS_ARCH_HASWELL;
#endif
#ifdef BLIS_CONFIG_SANDYBRIDGE
		if ( bli_cpuid_is_sandybridge( family, model, features ) )
			return BLIS_ARCH_SANDYBRIDGE;
#endif
#ifdef BLIS_CONFIG_PENRYN
		if ( bli_cpuid_is_penryn( family, model, features ) )
			return BLIS_ARCH_PENRYN;
#endif
		// If none of the other sub-configurations were detected, return
		// the 'generic' arch_t id value.
		return BLIS_ARCH_GENERIC;
	}
	else if ( vendor == VENDOR_AMD )
	{

		// Check for each AMD configuration that is enabled, check for that
		// microarchitecture. We check from most recent to most dated.
#ifdef BLIS_CONFIG_ZEN3
		if ( bli_cpuid_is_zen3( family, model, features ) )
			return BLIS_ARCH_ZEN3;
#endif
#ifdef BLIS_CONFIG_ZEN2
		if ( bli_cpuid_is_zen2( family, model, features ) )
			return BLIS_ARCH_ZEN2;
#endif
#ifdef BLIS_CONFIG_ZEN
		if ( bli_cpuid_is_zen( family, model, features ) )
			return BLIS_ARCH_ZEN;
#endif
#ifdef BLIS_CONFIG_EXCAVATOR
		if ( bli_cpuid_is_excavator( family, model, features ) )
			return BLIS_ARCH_EXCAVATOR;
#endif
#ifdef BLIS_CONFIG_STEAMROLLER
		if ( bli_cpuid_is_steamroller( family, model, features ) )
			return BLIS_ARCH_STEAMROLLER;
#endif
#ifdef BLIS_CONFIG_PILEDRIVER
		if ( bli_cpuid_is_piledriver( family, model, features ) )
			return BLIS_ARCH_PILEDRIVER;
#endif
#ifdef BLIS_CONFIG_BULLDOZER
		if ( bli_cpuid_is_bulldozer( family, model, features ) )
			return BLIS_ARCH_BULLDOZER;
#endif
		// If none of the other sub-configurations were detected, return
		// the 'generic' arch_t id value.
		return BLIS_ARCH_GENERIC;
	}
	else if ( vendor == VENDOR_UNKNOWN )
	{
		return BLIS_ARCH_GENERIC;
	}

	return BLIS_ARCH_GENERIC;
}

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

bool bli_cpuid_is_skx
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_AVX      |
	                          FEATURE_FMA3     |
	                          FEATURE_AVX2     |
	                          FEATURE_AVX512F  |
	                          FEATURE_AVX512DQ |
	                          FEATURE_AVX512BW |
	                          FEATURE_AVX512VL ;


	int nvpu = vpu_count();

	if ( bli_cpuid_has_features( features, expected ) )
	{
		switch ( nvpu )
		{
		case 1:
			bli_arch_log( "Hardware has 1 FMA unit; using 'haswell' (not 'skx') sub-config.\n" );
			return FALSE;
		case 2:
			bli_arch_log( "Hardware has 2 FMA units; using 'skx' sub-config.\n" );
			return TRUE;
		default:
			bli_arch_log( "Number of FMA units unknown; using 'haswell' (not 'skx') config.\n" );
			return FALSE;
		}
	}
	else
		return FALSE;

	return TRUE;
}

bool bli_cpuid_is_knl
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_AVX     |
	                          FEATURE_FMA3    |
	                          FEATURE_AVX2    |
	                          FEATURE_AVX512F |
	                          FEATURE_AVX512PF;

	if ( !bli_cpuid_has_features( features, expected ) ) return FALSE;

	return TRUE;
}

bool bli_cpuid_is_haswell
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_AVX  |
	                          FEATURE_FMA3 |
	                          FEATURE_AVX2;

	if ( !bli_cpuid_has_features( features, expected ) ) return FALSE;

	return TRUE;
}

bool bli_cpuid_is_sandybridge
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_AVX;

	if ( !bli_cpuid_has_features( features, expected ) ) return FALSE;

	return TRUE;
}

bool bli_cpuid_is_penryn
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_SSE3 |
	                          FEATURE_SSSE3;

	if ( !bli_cpuid_has_features( features, expected ) ) return FALSE;

	return TRUE;
}

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

bool bli_cpuid_is_zen3
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_AVX  |
	                          FEATURE_FMA3 |
	                          FEATURE_AVX2;

	if ( !bli_cpuid_has_features( features, expected ) ) return FALSE;

	// All Zen3 cores have a family of 0x19.
	if ( family != 0x19 ) return FALSE;

	// Finally, check for specific models:
	// - 0x00 ~ 0xff
	// NOTE: We accept any model because the family 25 (0x19) is unique.
	const bool is_arch
	=
	( 0x00 <= model && model <= 0xff );

	if ( !is_arch ) return FALSE;

	return TRUE;
}

bool bli_cpuid_is_zen2
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_AVX  |
	                          FEATURE_FMA3 |
	                          FEATURE_AVX2;

	if ( !bli_cpuid_has_features( features, expected ) ) return FALSE;

	// All Zen2 cores have a family of 0x17.
	if ( family == 0x17 ) {
		return 0x30 <= model && model <= 0xff;
	}

#ifndef BLIS_CONFIG_ZEN3
	// Fallback to Zen 2 kernels on Zen 3, when blis is compiled without
	// Zen 3 support (e.g. because it requires a newer compiler).
	if ( family == 0x19 ) {
		return 0x00 <= model && model <= 0xff;
	}
#endif

	return FALSE;
}

bool bli_cpuid_is_zen
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_AVX  |
	                          FEATURE_FMA3 |
	                          FEATURE_AVX2;

	if ( !bli_cpuid_has_features( features, expected ) ) return FALSE;

	// All Zen cores have a family of 0x17.
	if ( family != 0x17 ) return FALSE;

	// Finally, check for specific models:
	// - 0x00 ~ 0x2f
	// NOTE: We must check model because the family 23 (0x17) is shared with
	// zen2.
	const bool is_arch
	=
	( 0x00 <= model && model <= 0x2f );

	if ( !is_arch ) return FALSE;

	return TRUE;
}

bool bli_cpuid_is_excavator
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_AVX  |
	                          FEATURE_FMA3 |
	                          FEATURE_AVX2;

	if ( !bli_cpuid_has_features( features, expected ) ) return FALSE;

	// All Excavator cores have a family of 0x15.
	if ( family != 0x15 ) return FALSE;

	// Finally, check for specific models:
	// - 0x60 ~ 0x7f
	const bool is_arch
	=
	( 0x60 <= model && model <= 0x7f );

	if ( !is_arch ) return FALSE;

	return TRUE;
}

bool bli_cpuid_is_steamroller
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_AVX  |
	                          FEATURE_FMA3 |
	                          FEATURE_FMA4;

	if ( !bli_cpuid_has_features( features, expected ) ) return FALSE;

	// All Steamroller cores have a family of 0x15.
	if ( family != 0x15 ) return FALSE;

	// Finally, check for specific models:
	// - 0x30 ~ 0x3f
	const bool is_arch
	=
	( 0x30 <= model && model <= 0x3f );

	if ( !is_arch ) return FALSE;

	return TRUE;
}

bool bli_cpuid_is_piledriver
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_AVX  |
	                          FEATURE_FMA3 |
	                          FEATURE_FMA4;

	if ( !bli_cpuid_has_features( features, expected ) ) return FALSE;

	// All Piledriver cores have a family of 0x15.
	if ( family != 0x15 ) return FALSE;

	// Finally, check for specific models:
	// - 0x02
	// - 0x10 ~ 0x1f
	const bool is_arch
	=
	model == 0x02 || ( 0x10 <= model && model <= 0x1f );

	if ( !is_arch ) return FALSE;

	return TRUE;
}

bool bli_cpuid_is_bulldozer
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_AVX |
	                          FEATURE_FMA4;

	if ( !bli_cpuid_has_features( features, expected ) ) return FALSE;

	// All Bulldozer cores have a family of 0x15.
	if ( family != 0x15 ) return FALSE;

	// Finally, check for specific models:
	// - 0x00
	// - 0x01
	const bool is_arch
	=
	( model == 0x00 || model == 0x01 );

	if ( !is_arch ) return FALSE;

	return TRUE;
}

#elif defined(__aarch64__) || defined(__arm__) || defined(_M_ARM)

arch_t bli_cpuid_query_id( void )
{
	uint32_t vendor, model, part, features;

	vendor = bli_cpuid_query( &model, &part, &features );

#if 0
	printf( "vendor   = %u\n", vendor );
	printf( "model    = %u\n", model );
	printf( "part     = 0x%x\n", part );
	printf( "features = %u\n", features );
#endif



	if ( vendor == VENDOR_ARM )
	{
		if ( model == MODEL_ARMV8 )
		{
			return part;
			// Check for each ARMv8 configuration that is enabled, check for that
			// microarchitecture. We check from most recent to most dated.
			// If none of the other sub-configurations were detected, return
			// the 'generic' arch_t id value.
			return BLIS_ARCH_GENERIC;
		}
		else if ( model == MODEL_ARMV7 )
		{
			// Check for each ARMv7 configuration that is enabled, check for that
			// microarchitecture. We check from most recent to most dated.
#ifdef BLIS_CONFIG_CORTEXA15
			if ( bli_cpuid_is_cortexa15( model, part, features ) )
				return BLIS_ARCH_CORTEXA15;
#endif
#ifdef BLIS_CONFIG_CORTEXA9
			if ( bli_cpuid_is_cortexa9( model, part, features ) )
				return BLIS_ARCH_CORTEXA9;
#endif
			// If none of the other sub-configurations were detected, return
			// the 'generic' arch_t id value.
			return BLIS_ARCH_GENERIC;
		}
	}
	else if ( vendor == VENDOR_UNKNOWN )
	{
		return BLIS_ARCH_GENERIC;
	}

	return BLIS_ARCH_GENERIC;
}

bool bli_cpuid_is_cortexa15
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_NEON;

	return bli_cpuid_has_features( features, expected ) && model == 0xc0f;
}

bool bli_cpuid_is_cortexa9
     (
       uint32_t family,
       uint32_t model,
       uint32_t features
     )
{
	// Check for expected CPU features.
	const uint32_t expected = FEATURE_NEON;

	return bli_cpuid_has_features( features, expected ) && model == 0xc09;
}

#endif

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

//
// This section of the file was based off of cpuid.cxx from TBLIS [1].
//
// [1] https://github.com/devinamatthews/tblis
//

/*

   Copyright (C) 2017, The University of Texas at Austin
   Copyright (C) 2017, Devin Matthews
   Copyright (C) 2018 - 2019, Advanced Micro Devices, Inc.

   Redistribution and use in source and binary forms, with or without
   modification, are permitted provided that the following conditions are
   met:
    - Redistributions of source code must retain the above copyright
      notice, this list of conditions and the following disclaimer.
    - Redistributions in binary form must reproduce the above copyright
      notice, this list of conditions and the following disclaimer in the
      documentation and/or other materials provided with the distribution.
    - Neither the name(s) of the copyright holder(s) nor the names of its
      contributors may be used to endorse or promote products derived
      from this software without specific prior written permission.

   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
   HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.

*/

#if defined(__x86_64__) || defined(_M_X64) || defined(__i386) || defined(_M_IX86)

enum
{
                                      // input register(s)     output register
	FEATURE_MASK_SSE3     = (1u<< 0), // cpuid[eax=1]         :ecx[0]
	FEATURE_MASK_SSSE3    = (1u<< 9), // cpuid[eax=1]         :ecx[9]
	FEATURE_MASK_SSE41    = (1u<<19), // cpuid[eax=1]         :ecx[19]
	FEATURE_MASK_SSE42    = (1u<<20), // cpuid[eax=1]         :ecx[20]
	FEATURE_MASK_AVX      = (1u<<28), // cpuid[eax=1]         :ecx[28]
	FEATURE_MASK_AVX2     = (1u<< 5), // cpuid[eax=7,ecx=0]   :ebx[5]
	FEATURE_MASK_FMA3     = (1u<<12), // cpuid[eax=1]         :ecx[12]
	FEATURE_MASK_FMA4     = (1u<<16), // cpuid[eax=0x80000001]:ecx[16]
	FEATURE_MASK_AVX512F  = (1u<<16), // cpuid[eax=7,ecx=0]   :ebx[16]
	FEATURE_MASK_AVX512DQ = (1u<<17), // cpuid[eax=7,ecx=0]   :ebx[17]
	FEATURE_MASK_AVX512PF = (1u<<26), // cpuid[eax=7,ecx=0]   :ebx[26]
	FEATURE_MASK_AVX512ER = (1u<<27), // cpuid[eax=7,ecx=0]   :ebx[27]
	FEATURE_MASK_AVX512CD = (1u<<28), // cpuid[eax=7,ecx=0]   :ebx[28]
	FEATURE_MASK_AVX512BW = (1u<<30), // cpuid[eax=7,ecx=0]   :ebx[30]
	FEATURE_MASK_AVX512VL = (1u<<31), // cpuid[eax=7,ecx=0]   :ebx[31]
	FEATURE_MASK_XGETBV   = (1u<<26)|
                            (1u<<27), // cpuid[eax=1]         :ecx[27:26]
	XGETBV_MASK_XMM       = 0x02u,    // xcr0[1]
	XGETBV_MASK_YMM       = 0x04u,    // xcr0[2]
	XGETBV_MASK_ZMM       = 0xe0u     // xcr0[7:5]
};


uint32_t bli_cpuid_query
     (
       uint32_t* family,
       uint32_t* model,
       uint32_t* features
     )
{
	uint32_t eax, ebx, ecx, edx;

	uint32_t old_model  = 0;
	uint32_t old_family = 0;
	uint32_t ext_model  = 0;
	uint32_t ext_family = 0;

	*family   = 0;
	*model    = 0;
	*features = 0;

	//fprintf( stderr, "checking cpuid\n" );

	uint32_t cpuid_max     = __get_cpuid_max( 0,           0 );
	uint32_t cpuid_max_ext = __get_cpuid_max( 0x80000000u, 0 );

	//fprintf( stderr, "max cpuid leaf: %d\n", cpuid_max );
	//fprintf( stderr, "max extended cpuid leaf: %08x\n", cpuid_max_ext );

	if ( cpuid_max < 1 ) return VENDOR_UNKNOWN;

	// The fourth '0' serves as the NULL-terminator for the vendor string.
	uint32_t vendor_string[4] = { 0, 0, 0, 0 };

	// This is actually a macro that modifies the last four operands,
	// hence why they are not passed by address.
	__cpuid( 0, eax, vendor_string[0],
	                 vendor_string[2],
	                 vendor_string[1] );

	// Check extended feature bits for post-AVX2 features.
	if ( cpuid_max >= 7 )
	{
		// This is actually a macro that modifies the last four operands,
		// hence why they are not passed by address.
		__cpuid_count( 7, 0, eax, ebx, ecx, edx );

		//fprintf( stderr, "cpuid leaf 7:\n" );
		//print_binary( eax );
		//print_binary( ebx );
		//print_binary( ecx );
		//print_binary( edx );

		if ( bli_cpuid_has_features( ebx, FEATURE_MASK_AVX2     ) ) *features |= FEATURE_AVX2;
		if ( bli_cpuid_has_features( ebx, FEATURE_MASK_AVX512F  ) ) *features |= FEATURE_AVX512F;
		if ( bli_cpuid_has_features( ebx, FEATURE_MASK_AVX512DQ ) ) *features |= FEATURE_AVX512DQ;
		if ( bli_cpuid_has_features( ebx, FEATURE_MASK_AVX512PF ) ) *features |= FEATURE_AVX512PF;
		if ( bli_cpuid_has_features( ebx, FEATURE_MASK_AVX512ER ) ) *features |= FEATURE_AVX512ER;
		if ( bli_cpuid_has_features( ebx, FEATURE_MASK_AVX512CD ) ) *features |= FEATURE_AVX512CD;
		if ( bli_cpuid_has_features( ebx, FEATURE_MASK_AVX512BW ) ) *features |= FEATURE_AVX512BW;
		if ( bli_cpuid_has_features( ebx, FEATURE_MASK_AVX512VL ) ) *features |= FEATURE_AVX512VL;
	}

	// Check extended processor info / features bits for AMD-specific features.
	if ( cpuid_max_ext >= 0x80000001u )
	{
		// This is actually a macro that modifies the last four operands,
		// hence why they are not passed by address.
		__cpuid( 0x80000001u, eax, ebx, ecx, edx );

		//fprintf(stderr, "extended cpuid leaf 0x80000001:\n");
		//print_binary(eax);
		//print_binary(ebx);
		//print_binary(ecx);
		//print_binary(edx);

		if ( bli_cpuid_has_features( ecx, FEATURE_MASK_FMA4 ) ) *features |= FEATURE_FMA4;
	}

	// Unconditionally check processor info / features bits.
	{
		// This is actually a macro that modifies the last four operands,
		// hence why they are not passed by address.
		__cpuid( 1, eax, ebx, ecx, edx );

		//fprintf(stderr, "cpuid leaf 1:\n");
		//print_binary(eax);
		//print_binary(ebx);
		//print_binary(ecx);
		//print_binary(edx);

		/*
		   cpuid(eax=1): eax[27:0]

			3: 0 - Stepping
			7: 4 - Model
		   11: 8 - Family
		   13:12 - Processor Type
		   19:16 - Extended Model
		   27:20 - Extended Family

		   Intel and AMD have suggested applications to display the family of a
		   CPU as the sum of the "Family" and the "Extended Family" fields shown
		   above, and the model as the sum of the "Model" and the 4-bit
		   left-shifted "Extended Model" fields. If "Family" is different than
		   6 or 15, only the "Family" and "Model" fields should be used while the
		   "Extended Family" and "Extended Model" bits are reserved. If "Family"
		   is set to 15, then "Extended Family" and the 4-bit left-shifted
		   "Extended Model" should be added to the respective base values, and if
		   "Family" is set to 6, then only the 4-bit left-shifted "Extended Model"
		   should be added to "Model".
		*/

		old_model  = ( eax >>  4 ) & ( 0xF  ); // bits 7:4
		old_family = ( eax >>  8 ) & ( 0xF  ); // bits 11:8

		ext_model  = ( eax >> 16 ) & ( 0xF  ); // bits 19:16
		ext_family = ( eax >> 20 ) & ( 0xFF ); // bits 27:20

		// Set the display model and family values based on the original family
		// value. See explanation above.
		if      ( old_family == 6 )
		{
			*model  = ( ext_model << 4 ) + old_model;
			*family =                      old_family;
		}
		else if ( old_family == 15 )
		{
			*model  = ( ext_model << 4 ) + old_model;
			*family = ( ext_family     ) + old_family;
		}
		else
		{
			*model  =                      old_model;
			*family =                      old_family;
		}

		// Check for SSE, AVX, and FMA3 features.
		if ( bli_cpuid_has_features( ecx, FEATURE_MASK_SSE3  ) ) *features |= FEATURE_SSE3;
		if ( bli_cpuid_has_features( ecx, FEATURE_MASK_SSSE3 ) ) *features |= FEATURE_SSSE3;
		if ( bli_cpuid_has_features( ecx, FEATURE_MASK_SSE41 ) ) *features |= FEATURE_SSE41;
		if ( bli_cpuid_has_features( ecx, FEATURE_MASK_SSE42 ) ) *features |= FEATURE_SSE42;
		if ( bli_cpuid_has_features( ecx, FEATURE_MASK_AVX   ) ) *features |= FEATURE_AVX;
		if ( bli_cpuid_has_features( ecx, FEATURE_MASK_FMA3  ) ) *features |= FEATURE_FMA3;

		// Check whether the hardware supports xsave/xrestor/xsetbv/xgetbv AND 
		// support for these is enabled by the OS. If so, then we proceed with
		// checking that various register-state saving features are available.
		if ( bli_cpuid_has_features( ecx, FEATURE_MASK_XGETBV ) )
		{
			uint32_t xcr = 0;

			// Call xgetbv to get xcr0 (the extended control register) copied
			// to [edx:eax]. This encodes whether software supports various
			// register state-saving features.
			__asm__ __volatile__
			(
				".byte 0x0F, 0x01, 0xD0"
				: "=a" (eax),
				  "=d" (edx)
				: "c"  (xcr)
				: "cc"
			);

			//fprintf(stderr, "xcr0:\n");
			//print_binary(eax);
			//print_binary(edx);

			//fprintf(stderr, "xgetbv: xmm: %d\n", bli_cpuid_has_features(eax, XGETBV_MASK_XMM));
			//fprintf(stderr, "xgetbv: ymm: %d\n", bli_cpuid_has_features(eax, XGETBV_MASK_XMM|
			//                                                XGETBV_MASK_YMM));
			//fprintf(stderr, "xgetbv: zmm: %d\n", bli_cpuid_has_features(eax, XGETBV_MASK_XMM|
			//                                                XGETBV_MASK_YMM|
			//                                                XGETBV_MASK_ZMM));

			// The OS can manage the state of 512-bit zmm (AVX-512) registers
			// only if the xcr[7:5] bits are set. If they are not set, then
			// clear all feature bits related to AVX-512. 
			if ( !bli_cpuid_has_features( eax, XGETBV_MASK_XMM |
				                               XGETBV_MASK_YMM |
				                               XGETBV_MASK_ZMM ) )
			{
				*features &= ~( FEATURE_AVX512F  |
				                FEATURE_AVX512DQ |
				                FEATURE_AVX512PF |
				                FEATURE_AVX512ER |
				                FEATURE_AVX512CD |
				                FEATURE_AVX512BW |
				                FEATURE_AVX512VL );
			}

			// The OS can manage the state of 256-bit ymm (AVX) registers
			// only if the xcr[2] bit is set. If it is not set, then
			// clear all feature bits related to AVX. 
			if ( !bli_cpuid_has_features( eax, XGETBV_MASK_XMM |
				                               XGETBV_MASK_YMM ) )
			{
				*features &= ~( FEATURE_AVX  |
				                FEATURE_AVX2 |
				                FEATURE_FMA3 |
				                FEATURE_FMA4 );
			}

			// The OS can manage the state of 128-bit xmm (SSE) registers
			// only if the xcr[1] bit is set. If it is not set, then
			// clear all feature bits related to SSE (which means the
			// entire bitfield is clear). 
			if ( !bli_cpuid_has_features( eax, XGETBV_MASK_XMM ) )
			{
				*features = 0;
			}
		}
		else
		{
			// If the hardware does not support xsave/xrestor/xsetbv/xgetbv,
			// OR these features are not enabled by the OS, then we clear
			// the bitfield, because it means that not even xmm support is
			// present.

			//fprintf(stderr, "xgetbv: no\n");
			features = 0;
		}
	}

	//fprintf(stderr, "vendor: %12s\n", vendor_string);
	//fprintf(stderr, "family: %d\n", family);
	//fprintf(stderr, "model: %d\n", model);
	//fprintf(stderr, "sse3: %d\n", bli_cpuid_has_features(features, FEATURE_SSE3));
	//fprintf(stderr, "ssse3: %d\n", bli_cpuid_has_features(features, FEATURE_SSSE3));
	//fprintf(stderr, "sse4.1: %d\n", bli_cpuid_has_features(features, FEATURE_SSE41));
	//fprintf(stderr, "sse4.2: %d\n", bli_cpuid_has_features(features, FEATURE_SSE42));
	//fprintf(stderr, "avx: %d\n", bli_cpuid_has_features(features, FEATURE_AVX));
	//fprintf(stderr, "avx2: %d\n", bli_cpuid_has_features(features, FEATURE_AVX2));
	//fprintf(stderr, "fma3: %d\n", bli_cpuid_has_features(features, FEATURE_FMA3));
	//fprintf(stderr, "fma4: %d\n", bli_cpuid_has_features(features, FEATURE_FMA4));
	//fprintf(stderr, "avx512f: %d\n", bli_cpuid_has_features(features, FEATURE_AVX512F));
	//fprintf(stderr, "avx512pf: %d\n", bli_cpuid_has_features(features, FEATURE_AVX512PF));
	//fprintf(stderr, "avx512dq: %d\n", bli_cpuid_has_features(features, FEATURE_AVX512DQ));

	// Check the vendor string and return a value to indicate Intel or AMD.
	if      ( strcmp( ( char* )vendor_string, "AuthenticAMD" ) == 0 )
		return VENDOR_AMD;
	else if ( strcmp( ( char* )vendor_string, "GenuineIntel" ) == 0 )
		return VENDOR_INTEL;
	else
		return VENDOR_UNKNOWN;
}

void get_cpu_name( char *cpu_name )
{
	uint32_t eax, ebx, ecx, edx;

	__cpuid( 0x80000002u, eax, ebx, ecx, edx );
	//printf("%x %x %x %x\n", eax, ebx, ecx, edx);

	*( uint32_t* )&cpu_name[0 + 0] = eax;
	*( uint32_t* )&cpu_name[0 + 4] = ebx;
	*( uint32_t* )&cpu_name[0 + 8] = ecx;
	*( uint32_t* )&cpu_name[0 +12] = edx;

	__cpuid( 0x80000003u, eax, ebx, ecx, edx );
	//printf("%x %x %x %x\n", eax, ebx, ecx, edx);

	*( uint32_t* )&cpu_name[16+ 0] = eax;
	*( uint32_t* )&cpu_name[16+ 4] = ebx;
	*( uint32_t* )&cpu_name[16+ 8] = ecx;
	*( uint32_t* )&cpu_name[16+12] = edx;

	__cpuid( 0x80000004u, eax, ebx, ecx, edx );
	//printf("%x %x %x %x\n", eax, ebx, ecx, edx);

	*( uint32_t* )&cpu_name[32+ 0] = eax;
	*( uint32_t* )&cpu_name[32+ 4] = ebx;
	*( uint32_t* )&cpu_name[32+ 8] = ecx;
	*( uint32_t* )&cpu_name[32+12] = edx;
}

// Return the number of FMA units _assuming avx512 is supported_.
// This needs updating for new processor types, sigh.
// See https://ark.intel.com/content/www/us/en/ark.html#@Processors
// and also https://github.com/jeffhammond/vpu-count
int vpu_count( void )
{
	char  cpu_name[48] = {};
	char* loc;
	char  model_num[5];
	int   sku;

	get_cpu_name( cpu_name );

	if ( strstr( cpu_name, "Intel(R) Xeon(R)" ) != NULL )
	{
		if (( loc = strstr( cpu_name, "Platinum" ) ))
			return 2;
		if ( loc == NULL )
			loc = strstr( cpu_name, "Gold" ); // 1 or 2, tested below
		if ( loc == NULL )
			if (( loc = strstr( cpu_name, "Silver" ) ))
				return 1;
		if ( loc == NULL )
			if (( loc = strstr( cpu_name, "Bronze" ) ))
				return 1;
		if ( loc == NULL )
			loc = strstr( cpu_name, "W" );
		if ( loc == NULL )
			if (( loc = strstr( cpu_name, "D" ) ))
				// Fixme:  May be wrong
				// <https://github.com/jeffhammond/vpu-count/issues/3#issuecomment-542044651>
				return 1;
		if ( loc == NULL )
			return -1;

		// We may have W-nnnn rather than, say, Gold nnnn
		if ( 'W' == *loc && '-' == *(loc+1) )
			loc++;
		else
			loc = strstr( loc+1, " " );
		if ( loc == NULL )
			return -1;

		strncpy( model_num, loc+1, 4 );
		model_num[4] = '\0'; // Things like i9-10900X matched above

		sku = atoi( model_num );

		// These were derived from ARK listings as of 2019-10-09, but
		// may not be complete, especially as the ARK Skylake listing
		// seems to be limited.
		if      ( 8199 >= sku && sku >= 8100 ) return 2;
		else if ( 6199 >= sku && sku >= 6100 ) return 2;
		else if (                sku == 5122 ) return 2;
		else if ( 6299 >= sku && sku >= 6200 ) return 2; // Cascade Lake Gold
		else if ( 5299 >= sku && sku >= 5200 ) return 1; // Cascade Lake Gold
		else if ( 5199 >= sku && sku >= 5100 ) return 1;
		else if ( 4199 >= sku && sku >= 4100 ) return 1;
		else if ( 3199 >= sku && sku >= 3100 ) return 1;
		else if ( 3299 >= sku && sku >= 3200 ) return 2; // Cascade Lake W
		else if ( 2299 >= sku && sku >= 2200 ) return 2; // Cascade Lake W
		else if ( 2199 >= sku && sku >= 2120 ) return 2;
		else if ( 2102 == sku || sku == 2104 ) return 2; // Gold exceptions
		else if ( 2119 >= sku && sku >= 2100 ) return 1;
		else return -1;
	}
	else if ( strstr( cpu_name, "Intel(R) Core(TM)" ) != NULL )
		return 2; // All i7/i9 with avx512?
	else
	{
		return -1;
	}
}

#elif defined(__aarch64__)

#ifdef __linux__
// This is adapted from OpenBLAS.  See
// https://www.kernel.org/doc/html/latest/arm64/cpu-feature-registers.html
// for the mechanism, but not the magic numbers.

// Fixme:  Could these be missing in older Linux?
#include <asm/hwcap.h>
#include <sys/auxv.h>

#ifndef HWCAP_CPUID
#define HWCAP_CPUID (1 << 11)
#endif
/* From https://www.kernel.org/doc/html/latest/arm64/sve.html and the
   aarch64 hwcap.h */
#ifndef HWCAP_SVE
#define HWCAP_SVE (1 << 22)
#endif
/* Maybe also for AT_HWCAP2
#define HWCAP2_SVE2(1 << 1)
et al
) */

#endif //__linux__

#ifdef __APPLE__
#include <sys/types.h>
// #include <sys/sysctl.h>
#endif

static uint32_t get_coretype
	(
	  uint32_t* features
	)
{
	int implementer = 0x00, part = 0x000;
	*features = FEATURE_NEON;

#ifdef __linux__
	if ( getauxval( AT_HWCAP ) & HWCAP_CPUID )
	{
		// Also available from
		// /sys/devices/system/cpu/cpu0/regs/identification/midr_el1
		// and split out in /proc/cpuinfo (with a tab before the colon):
		// CPU part	: 0x0a1
		
		uint64_t midr_el1;
		__asm("mrs %0, MIDR_EL1" : "=r" (midr_el1));
		/*
		 * MIDR_EL1
		 *
		 * 31          24 23     20 19          16 15          4 3         0
		 * -----------------------------------------------------------------
		 * | Implementer | Variant | Architecture | Part Number | Revision |
		 * -----------------------------------------------------------------
		 */
		implementer = (midr_el1 >> 24) & 0xFF;
		part        = (midr_el1 >> 4)  & 0xFFF;
	}
	
	bool has_sve = getauxval( AT_HWCAP ) & HWCAP_SVE;
	if (has_sve)
		*features |= FEATURE_SVE;
#endif //__linux__

#ifdef __APPLE__
	// Better values could be obtained from sysctlbyname()
	implementer = 0x61; //Apple
	part        = 0x023; //Firestorm
#endif //__APPLE__

	// From Linux arch/arm64/include/asm/cputype.h
	// ARM_CPU_IMP_ARM 0x41
	// ARM_CPU_IMP_APM 0x50
	// ARM_CPU_IMP_CAVIUM 0x43
	// ARM_CPU_IMP_BRCM 0x42
	// ARM_CPU_IMP_QCOM 0x51
	// ARM_CPU_IMP_NVIDIA 0x4E
	// ARM_CPU_IMP_FUJITSU 0x46
	// ARM_CPU_IMP_HISI 0x48
	// ARM_CPU_IMP_APPLE 0x61
	//
	// ARM_CPU_PART_AEM_V8 0xD0F
	// ARM_CPU_PART_FOUNDATION 0xD00
	// ARM_CPU_PART_CORTEX_A57 0xD07
	// ARM_CPU_PART_CORTEX_A72 0xD08
	// ARM_CPU_PART_CORTEX_A53 0xD03
	// ARM_CPU_PART_CORTEX_A73 0xD09
	// ARM_CPU_PART_CORTEX_A75 0xD0A
	// ARM_CPU_PART_CORTEX_A35 0xD04
	// ARM_CPU_PART_CORTEX_A55 0xD05
	// ARM_CPU_PART_CORTEX_A76 0xD0B
	// ARM_CPU_PART_NEOVERSE_N1 0xD0C
	// ARM_CPU_PART_CORTEX_A77 0xD0D
	//   from GCC:
	// ARM_CPU_PART_CORTEX_A78 0xd41
	// ARM_CPU_PART_CORTEX_X1 0xd44
	// ARM_CPU_PART_CORTEX_V1 0xd40
	// ARM_CPU_PART_CORTEX_N2 0xd49
	// ARM_CPU_PART_CORTEX_R82 0xd15
	//
	// APM_CPU_PART_POTENZA 0x000
	//
	// CAVIUM_CPU_PART_THUNDERX 0x0A1
	// CAVIUM_CPU_PART_THUNDERX_81XX 0x0A2
	// CAVIUM_CPU_PART_THUNDERX_83XX 0x0A3
	// CAVIUM_CPU_PART_THUNDERX2 0x0AF
	// CAVIUM_CPU_PART_THUNDERX3 0x0B8  // taken from OpenBLAS
	//
	// BRCM_CPU_PART_BRAHMA_B53 0x100 
	// BRCM_CPU_PART_VULCAN 0x516
	//
	// QCOM_CPU_PART_FALKOR_V1 0x800
	// QCOM_CPU_PART_FALKOR 0xC00
	// QCOM_CPU_PART_KRYO 0x200
	// QCOM_CPU_PART_KRYO_3XX_SILVER 0x803
	// QCOM_CPU_PART_KRYO_4XX_GOLD 0x804
	// QCOM_CPU_PART_KRYO_4XX_SILVER 0x805
	//
	// NVIDIA_CPU_PART_DENVER 0x003
	// NVIDIA_CPU_PART_CARMEL 0x004
	//
	// FUJITSU_CPU_PART_A64FX 0x001
	//
	// HISI_CPU_PART_TSV110 0xD01

	// APPLE_CPU_PART_M1_ICESTORM 0x022
	// APPLE_CPU_PART_M1_FIRESTORM 0x023

	// Fixme:  After merging the vpu_count branch we could report the
	// part here with bli_dolog.
	switch(implementer)
	{
		case 0x41:		// ARM
			switch (part)
			{
#ifdef BLIS_CONFIG_CORTEXA57
				case 0xd07: // Cortex A57
					return BLIS_ARCH_CORTEXA57;
#endif
#ifdef BLIS_CONFIG_CORTEXA53
				case 0xd03: // Cortex A53
					return BLIS_ARCH_CORTEXA53;
#endif
#ifdef BLIS_CONFIG_THUNDERX2
				case 0xd0c: // Neoverse N1 (and Graviton G2?)
					return BLIS_ARCH_THUNDERX2; //placeholder for N1
#endif
			}
			break;
		case 0x42:		// Broadcom
			switch (part)
			{
#ifdef BLIS_CONFIG_THUNDERX2
				case 0x516: // Vulcan
					return BLIS_ARCH_THUNDERX2;
#endif
			}
			break;
		case 0x43:		// Cavium
			switch (part)
			{
#ifdef BLIS_CONFIG_THUNDERX2
				case 0x0af: // ThunderX2
				case 0x0b8: // ThunderX3
					return BLIS_ARCH_THUNDERX2;
#endif
			}
			break;
		case 0x46:      	// Fujitsu
			switch (part)
			{
#ifdef BLIS_CONFIG_A64FX
				case 0x001: // A64FX
					return BLIS_ARCH_A64FX;
#endif
			}
			break;
		case 0x61:		// Apple
			switch (part)
			{
#ifdef BLIS_CONFIG_FIRESTORM
				case 0x022: // Icestorm (M1.LITTLE)
				case 0x023: // Firestorm (M1.big)
					return BLIS_ARCH_FIRESTORM;
#endif
			}
			break;
	}

#ifdef BLIS_CONFIG_ARMSVE
	if (has_sve)
		return BLIS_ARCH_ARMSVE;
#endif

// Can't use #if defined(...) here because of parsing done for autoconfiguration
#ifdef BLIS_CONFIG_CORTEXA57
	return BLIS_ARCH_CORTEXA57;
#else
#ifdef BLIS_CONFIG_CORTEXA53
	return BLIS_ARCH_CORTEXA53;
#else
	return BLIS_ARCH_GENERIC;
#endif
#endif
}

uint32_t bli_cpuid_query
     (
       uint32_t* model,
       uint32_t* part,
       uint32_t* features
     )
{
	*model = MODEL_ARMV8;
	*part  = get_coretype(features);

	return VENDOR_ARM;
}

#elif defined(__arm__) || defined(_M_ARM)

/* 
   I can't easily find documentation to do this as for aarch64, though
   it presumably could be unearthed from Linux code.  However, on
   Linux 5.2 (and Androids's 3.4), /proc/cpuinfo has this sort of
   thing, used below:

   CPU implementer	: 0x41
   CPU architecture: 7
   CPU variant	: 0x3
   CPU part	: 0xc09

   The complication for family selection is that Neon is optional for
   CortexA9, for instance.  That's tested in bli_cpuid_is_cortexa9.
 */

#define TEMP_BUFFER_SIZE 200

uint32_t bli_cpuid_query
     (
       uint32_t* model,
       uint32_t* part,
       uint32_t* features
     )
{
	*model    = MODEL_UNKNOWN;
    *part     = 0;
	*features = 0;

	char* pci_str = "/proc/cpuinfo";

	char  proc_str[ TEMP_BUFFER_SIZE ];
	char  ptno_str[ TEMP_BUFFER_SIZE ];
	char  feat_str[ TEMP_BUFFER_SIZE ];
	char* r_val;

	//printf( "bli_cpuid_query(): beginning search\n" );

	// Search /proc/cpuinfo for the 'Processor' entry.
	r_val = find_string_in( "Processor", proc_str, TEMP_BUFFER_SIZE, pci_str );
	if ( r_val == NULL ) return VENDOR_ARM;

	// Search /proc/cpuinfo for the 'CPU part' entry.
	r_val = find_string_in( "CPU part",  ptno_str, TEMP_BUFFER_SIZE, pci_str );
	if ( r_val == NULL ) return VENDOR_ARM;

	// Search /proc/cpuinfo for the 'Features' entry.
	r_val = find_string_in( "Features",  feat_str, TEMP_BUFFER_SIZE, pci_str );
	if ( r_val == NULL ) return VENDOR_ARM;

#if 0
	printf( "bli_cpuid_query(): full processor string: %s\n", proc_str );
	printf( "bli_cpuid_query(): full part num  string: %s\n", ptno_str );
	printf( "bli_cpuid_query(): full features  string: %s\n", feat_str );
#endif

	// Parse the feature string to check for SIMD features.
	if ( strstr( feat_str, "neon"  ) != NULL ||
	     strstr( feat_str, "asimd" ) != NULL )
		*features |= FEATURE_NEON;

	// Parse the feature string to check for SVE features.
	if ( strstr( feat_str, "sve" ) != NULL )
		*features |= FEATURE_SVE;

	//printf( "bli_cpuid_query(): features var: %u\n", *features );

	// Parse the processor string to uncover the model.
	if      ( strstr( proc_str, "ARMv7"   ) != NULL )
		*model = MODEL_ARMV7;
	else if ( strstr( proc_str, "AArch64" ) != NULL ||
              strstr( proc_str, "ARMv8"   ) )
		*model = MODEL_ARMV8;

	//printf( "bli_cpuid_query(): model: %u\n", *model );

	// Parse the part number string.
	r_val = strstr( ptno_str, "0x" );
    if ( r_val != NULL)
    {
	    *part = strtol( r_val, NULL, 16 );
    }
	//printf( "bli_cpuid_query(): part#: %x\n", *part );

	return VENDOR_ARM;
}

char* find_string_in( char* target, char* buffer, size_t buf_len, char* filepath )
{
	// This function searches for the first line of the file located at
	// 'filepath' that contains the string 'target' and then copies that
	// line (actually, the substring of the line starting with 'target')
	// to 'buffer', which is 'buf_len' bytes long.

	char* r_val = NULL;

	// Allocate a temporary local buffer equal to the size of buffer.
	char* buf_local = malloc( buf_len * sizeof( char ) );

	// Open the file stream.
	FILE* stream = fopen( filepath, "r" );

	// Repeatedly read in a line from the stream, storing the contents of
	// the stream into buf_local.
	while ( !feof( stream ) )
	{
		// Read in the current line, up to buf_len-1 bytes.
		r_val = fgets( buf_local, buf_len-1, stream );

		//printf( "read line: %s", buf_local );

		// fgets() returns the pointer specified by the first argument (in
		// this case, buf_local) on success and NULL on error.
		if ( r_val == NULL ) break;

		// Since fgets() was successful, we can search for the target string
		// within the current line, as captured in buf_local.
		r_val = strstr( buf_local, target );

		// If the target string was found in buf_local, we save it to buffer.
		if ( r_val != NULL )
		{
			//printf( "  found match to '%s'\n", target );

			// Copy the string read by fgets() to the caller's buffer.
			strncpy( buffer, buf_local, buf_len );

			// Make sure that we have a terminating null character by the
			// end of the buffer.
			if ( buf_len > 0 ) buffer[ buf_len - 1 ] = '\0';

			// Leave the loop since we found the target string.
			break;
		}
	}

	// Close the file stream.
	fclose( stream );

	// Free the temporary local buffer.
	free( buf_local );

	// Return r_val so the caller knows if we failed.
	return r_val;
}

#endif