gromacs-dev 4.6.5-1build1 / usr / include / gromacs / gmx_simd_macros.h

/*
 * This file is part of the GROMACS molecular simulation package.
 *
 * Copyright (c) 1991-2000, University of Groningen, The Netherlands.
 * Copyright (c) 2001-2012, The GROMACS Development Team
 * Copyright (c) 2012,2013, by the GROMACS development team, led by
 * David van der Spoel, Berk Hess, Erik Lindahl, and including many
 * others, as listed in the AUTHORS file in the top-level source
 * directory and at http://www.gromacs.org.
 *
 * GROMACS is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public License
 * as published by the Free Software Foundation; either version 2.1
 * of the License, or (at your option) any later version.
 *
 * GROMACS is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with GROMACS; if not, see
 * http://www.gnu.org/licenses, or write to the Free Software Foundation,
 * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA.
 *
 * If you want to redistribute modifications to GROMACS, please
 * consider that scientific software is very special. Version
 * control is crucial - bugs must be traceable. We will be happy to
 * consider code for inclusion in the official distribution, but
 * derived work must not be called official GROMACS. Details are found
 * in the README & COPYING files - if they are missing, get the
 * official version at http://www.gromacs.org.
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 * To help us fund GROMACS development, we humbly ask that you cite
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 */

/* The macros in this file are intended to be used for writing
 * architecture-independent SIMD intrinsics code.
 * To support a new architecture, adding macros here should be (nearly)
 * all that is needed.
 */

#ifdef _gmx_simd_macros_h_
#error "gmx_simd_macros.h included twice"
#else
#define _gmx_simd_macros_h_

/* NOTE: SSE2 acceleration does not include floor or blendv */


/* Uncomment the next line, without other SIMD active, for testing plain-C */
/* #define GMX_SIMD_REFERENCE_PLAIN_C */
#ifdef GMX_SIMD_REFERENCE_PLAIN_C
/* Plain C SIMD reference implementation, also serves as documentation */
#define GMX_HAVE_SIMD_MACROS

/* In general the reference SIMD supports any SIMD width, including 1.
 * See types/nb_verlet.h for details
 */
#define GMX_SIMD_REF_WIDTH  4

/* Include plain-C reference implementation, also serves as documentation */
#include "gmx_simd_ref.h"

#define GMX_SIMD_WIDTH_HERE  GMX_SIMD_REF_WIDTH

/* float/double SIMD register type */
#define gmx_mm_pr  gmx_simd_ref_pr

/* boolean SIMD register type */
#define gmx_mm_pb  gmx_simd_ref_pb

/* integer SIMD register type, only for table indexing and exclusion masks */
#define gmx_epi32  gmx_simd_ref_epi32
#define GMX_SIMD_EPI32_WIDTH  GMX_SIMD_REF_EPI32_WIDTH

/* Load GMX_SIMD_WIDTH_HERE reals for memory starting at r */
#define gmx_load_pr       gmx_simd_ref_load_pr
/* Set all SIMD register elements to *r */
#define gmx_load1_pr      gmx_simd_ref_load1_pr
#define gmx_set1_pr       gmx_simd_ref_set1_pr
#define gmx_setzero_pr    gmx_simd_ref_setzero_pr
#define gmx_store_pr      gmx_simd_ref_store_pr

#define gmx_add_pr        gmx_simd_ref_add_pr
#define gmx_sub_pr        gmx_simd_ref_sub_pr
#define gmx_mul_pr        gmx_simd_ref_mul_pr
/* For the FMA macros below, aim for c=d in code, so FMA3 uses 1 instruction */
#define gmx_madd_pr       gmx_simd_ref_madd_pr
#define gmx_nmsub_pr      gmx_simd_ref_nmsub_pr

#define gmx_max_pr        gmx_simd_ref_max_pr
#define gmx_blendzero_pr  gmx_simd_ref_blendzero_pr

#define gmx_round_pr      gmx_simd_ref_round_pr

/* Not required, only used to speed up the nbnxn tabulated PME kernels */
#define GMX_SIMD_HAVE_FLOOR
#ifdef GMX_SIMD_HAVE_FLOOR
#define gmx_floor_pr      gmx_simd_ref_floor_pr
#endif

/* Not required, only used when blendv is faster than comparison */
#define GMX_SIMD_HAVE_BLENDV
#ifdef GMX_SIMD_HAVE_BLENDV
#define gmx_blendv_pr     gmx_simd_ref_blendv_pr
#endif

/* Copy the sign of a to b, assumes b >= 0 for efficiency */
#define gmx_cpsgn_nonneg_pr  gmx_simd_ref_cpsgn_nonneg_pr

/* Very specific operation required in the non-bonded kernels */
#define gmx_masknot_add_pr   gmx_simd_ref_masknot_add_pr

/* Comparison */
#define gmx_cmplt_pr      gmx_simd_ref_cmplt_pr

/* Logical operations on SIMD booleans */
#define gmx_and_pb        gmx_simd_ref_and_pb
#define gmx_or_pb         gmx_simd_ref_or_pb

/* Returns a single int (0/1) which tells if any of the 4 booleans is True */
#define gmx_anytrue_pb    gmx_simd_ref_anytrue_pb

/* Conversions only used for PME table lookup */
#define gmx_cvttpr_epi32  gmx_simd_ref_cvttpr_epi32
#define gmx_cvtepi32_pr   gmx_simd_ref_cvtepi32_pr

/* These two function only need to be approximate, Newton-Raphson iteration
 * is used for full accuracy in gmx_invsqrt_pr and gmx_inv_pr.
 */
#define gmx_rsqrt_pr      gmx_simd_ref_rsqrt_pr
#define gmx_rcp_pr        gmx_simd_ref_rcp_pr

/* sqrt+inv+sin+cos+acos+atan2 are used for bonded potentials, exp for PME */
#define GMX_SIMD_HAVE_EXP
#ifdef GMX_SIMD_HAVE_EXP
#define gmx_exp_pr        gmx_simd_ref_exp_pr
#endif
#define GMX_SIMD_HAVE_TRIGONOMETRIC
#ifdef GMX_SIMD_HAVE_TRIGONOMETRIC
#define gmx_sqrt_pr       gmx_simd_ref_sqrt_pr
#define gmx_sincos_pr     gmx_simd_ref_sincos_pr
#define gmx_acos_pr       gmx_simd_ref_acos_pr
#define gmx_atan2_pr      gmx_simd_ref_atan2_pr
#endif

#endif /* GMX_SIMD_REFERENCE_PLAIN_C */


/* The same SIMD macros can be translated to SIMD intrinsics (and compiled
 * to instructions for) different SIMD width and float precision.
 *
 * On x86: The gmx_ prefix is replaced by _mm_ or _mm256_ (SSE or AVX).
 * The _pr suffix is replaced by _ps or _pd (for single or double precision).
 * Compiler settings will decide if 128-bit intrinsics will
 * be translated into SSE or AVX instructions.
 */


#ifdef GMX_USE_HALF_WIDTH_SIMD_HERE
#if defined GMX_X86_AVX_256
/* We have half SIMD width support, continue */
#else
#error "half SIMD width intrinsics are not supported"
#endif
#endif

#ifdef GMX_TARGET_X86

#ifdef GMX_X86_SSE2
/* This is for general x86 SIMD instruction sets that also support SSE2 */
#define GMX_HAVE_SIMD_MACROS

/* Include the highest supported x86 SIMD intrisics + math functions */
#ifdef GMX_X86_AVX_256
#include "gmx_x86_avx_256.h"
#ifdef GMX_DOUBLE
#include "gmx_math_x86_avx_256_double.h"
#else  /* GMX_DOUBLE */
#include "gmx_math_x86_avx_256_single.h"
#endif /* GMX_DOUBLE */
#else  /* GMX_X86_AVX_256 */
#ifdef GMX_X86_AVX_128_FMA
#include "gmx_x86_avx_128_fma.h"
#ifdef GMX_DOUBLE
#include "gmx_math_x86_avx_128_fma_double.h"
#else  /* GMX_DOUBLE */
#include "gmx_math_x86_avx_128_fma_single.h"
#endif /* GMX_DOUBLE */
#else  /* GMX_X86_AVX_128_FMA */
#ifdef GMX_X86_SSE4_1
#include "gmx_x86_sse4_1.h"
#ifdef GMX_DOUBLE
#include "gmx_math_x86_sse4_1_double.h"
#else  /* GMX_DOUBLE */
#include "gmx_math_x86_sse4_1_single.h"
#endif /* GMX_DOUBLE */
#else  /* GMX_X86_SSE4_1 */
#ifdef GMX_X86_SSE2
#include "gmx_x86_sse2.h"
#ifdef GMX_DOUBLE
#include "gmx_math_x86_sse2_double.h"
#else  /* GMX_DOUBLE */
#include "gmx_math_x86_sse2_single.h"
#endif /* GMX_DOUBLE */
#else  /* GMX_X86_SSE2 */
#error No x86 acceleration defined
#endif /* GMX_X86_SSE2 */
#endif /* GMX_X86_SSE4_1 */
#endif /* GMX_X86_AVX_128_FMA */
#endif /* GMX_X86_AVX_256 */

/* exp and trigonometric functions are included above */
#define GMX_SIMD_HAVE_EXP
#define GMX_SIMD_HAVE_TRIGONOMETRIC

#if !defined GMX_X86_AVX_256 || defined GMX_USE_HALF_WIDTH_SIMD_HERE

#ifndef GMX_DOUBLE

#define GMX_SIMD_WIDTH_HERE  4

#define gmx_mm_pr  __m128

#define gmx_mm_pb  __m128

#define gmx_epi32  __m128i
#define GMX_SIMD_EPI32_WIDTH  4

#define gmx_load_pr       _mm_load_ps
#define gmx_load1_pr      _mm_load1_ps
#define gmx_set1_pr       _mm_set1_ps
#define gmx_setzero_pr    _mm_setzero_ps
#define gmx_store_pr      _mm_store_ps

#define gmx_add_pr        _mm_add_ps
#define gmx_sub_pr        _mm_sub_ps
#define gmx_mul_pr        _mm_mul_ps
#ifdef GMX_X86_AVX_128_FMA
#define GMX_SIMD_HAVE_FMA
#define gmx_madd_pr(a, b, c)   _mm_macc_ps(a, b, c)
#define gmx_nmsub_pr(a, b, c)  _mm_nmacc_ps(a, b, c)
#else
#define gmx_madd_pr(a, b, c)   _mm_add_ps(c, _mm_mul_ps(a, b))
#define gmx_nmsub_pr(a, b, c)  _mm_sub_ps(c, _mm_mul_ps(a, b))
#endif
#define gmx_max_pr        _mm_max_ps
#define gmx_blendzero_pr  _mm_and_ps

#define gmx_cmplt_pr      _mm_cmplt_ps
#define gmx_and_pb        _mm_and_ps
#define gmx_or_pb         _mm_or_ps

#ifdef GMX_X86_SSE4_1
#define gmx_round_pr(x)   _mm_round_ps(x, 0x0)
#define GMX_SIMD_HAVE_FLOOR
#define gmx_floor_pr      _mm_floor_ps
#else
#define gmx_round_pr(x)   _mm_cvtepi32_ps(_mm_cvtps_epi32(x))
#endif

#ifdef GMX_X86_SSE4_1
#define GMX_SIMD_HAVE_BLENDV
#define gmx_blendv_pr     _mm_blendv_ps
#endif

static gmx_inline gmx_mm_pr gmx_cpsgn_nonneg_pr(gmx_mm_pr a, gmx_mm_pr b)
{
    /* The value -0.0 has only the sign-bit set */
    gmx_mm_pr sign_mask = _mm_set1_ps(-0.0);
    return _mm_or_ps(_mm_and_ps(a, sign_mask), b);
};

static gmx_inline gmx_mm_pr gmx_masknot_add_pr(gmx_mm_pb a, gmx_mm_pr b, gmx_mm_pr c)
{
    return _mm_add_ps(b, _mm_andnot_ps(a, c));
};

#define gmx_anytrue_pb    _mm_movemask_ps

#define gmx_cvttpr_epi32  _mm_cvttps_epi32
#define gmx_cvtepi32_pr   _mm_cvtepi32_ps

#define gmx_rsqrt_pr      _mm_rsqrt_ps
#define gmx_rcp_pr        _mm_rcp_ps

#define gmx_exp_pr        gmx_mm_exp_ps
#define gmx_sqrt_pr       gmx_mm_sqrt_ps
#define gmx_sincos_pr     gmx_mm_sincos_ps
#define gmx_acos_pr       gmx_mm_acos_ps
#define gmx_atan2_pr      gmx_mm_atan2_ps

#else /* ifndef GMX_DOUBLE */

#define GMX_SIMD_WIDTH_HERE  2

#define gmx_mm_pr  __m128d

#define gmx_mm_pb  __m128d

#define gmx_epi32  __m128i
#define GMX_SIMD_EPI32_WIDTH  4

#define gmx_load_pr       _mm_load_pd
#define gmx_load1_pr      _mm_load1_pd
#define gmx_set1_pr       _mm_set1_pd
#define gmx_setzero_pr    _mm_setzero_pd
#define gmx_store_pr      _mm_store_pd

#define gmx_add_pr        _mm_add_pd
#define gmx_sub_pr        _mm_sub_pd
#define gmx_mul_pr        _mm_mul_pd
#ifdef GMX_X86_AVX_128_FMA
#define GMX_SIMD_HAVE_FMA
#define gmx_madd_pr(a, b, c)   _mm_macc_pd(a, b, c)
#define gmx_nmsub_pr(a, b, c)  _mm_nmacc_pd(a, b, c)
#else
#define gmx_madd_pr(a, b, c)   _mm_add_pd(c, _mm_mul_pd(a, b))
#define gmx_nmsub_pr(a, b, c)  _mm_sub_pd(c, _mm_mul_pd(a, b))
#endif
#define gmx_max_pr        _mm_max_pd
#define gmx_blendzero_pr  _mm_and_pd

#ifdef GMX_X86_SSE4_1
#define gmx_round_pr(x)   _mm_round_pd(x, 0x0)
#define GMX_SIMD_HAVE_FLOOR
#define gmx_floor_pr      _mm_floor_pd
#else
#define gmx_round_pr(x)   _mm_cvtepi32_pd(_mm_cvtpd_epi32(x))
/* gmx_floor_pr is not used in code for pre-SSE4_1 hardware */
#endif

#ifdef GMX_X86_SSE4_1
#define GMX_SIMD_HAVE_BLENDV
#define gmx_blendv_pr     _mm_blendv_pd
#endif

static gmx_inline gmx_mm_pr gmx_cpsgn_nonneg_pr(gmx_mm_pr a, gmx_mm_pr b)
{
    gmx_mm_pr sign_mask = _mm_set1_pd(-0.0);
    return _mm_or_pd(_mm_and_pd(a, sign_mask), b);
};

static gmx_inline gmx_mm_pr gmx_masknot_add_pr(gmx_mm_pb a, gmx_mm_pr b, gmx_mm_pr c)
{
    return _mm_add_pd(b, _mm_andnot_pd(a, c));
};

#define gmx_cmplt_pr      _mm_cmplt_pd

#define gmx_and_pb        _mm_and_pd
#define gmx_or_pb         _mm_or_pd

#define gmx_anytrue_pb    _mm_movemask_pd

#define gmx_cvttpr_epi32  _mm_cvttpd_epi32
#define gmx_cvtepi32_pr   _mm_cvtepi32_pd

#define gmx_rsqrt_pr(r)   _mm_cvtps_pd(_mm_rsqrt_ps(_mm_cvtpd_ps(r)))
#define gmx_rcp_pr(r)     _mm_cvtps_pd(_mm_rcp_ps(_mm_cvtpd_ps(r)))

#define gmx_exp_pr        gmx_mm_exp_pd
#define gmx_sqrt_pr       gmx_mm_sqrt_pd
#define gmx_sincos_pr     gmx_mm_sincos_pd
#define gmx_acos_pr       gmx_mm_acos_pd
#define gmx_atan2_pr      gmx_mm_atan2_pd

#endif /* ifndef GMX_DOUBLE */

#else
/* We have GMX_X86_AVX_256 and not GMX_USE_HALF_WIDTH_SIMD_HERE,
 * so we use 256-bit SIMD.
 */

#ifndef GMX_DOUBLE

#define GMX_SIMD_WIDTH_HERE  8

#define gmx_mm_pr  __m256

#define gmx_mm_pb  __m256

#define gmx_epi32  __m256i
#define GMX_SIMD_EPI32_WIDTH  8

#define gmx_load_pr       _mm256_load_ps
#define gmx_load1_pr(x)   _mm256_set1_ps((x)[0])
#define gmx_set1_pr       _mm256_set1_ps
#define gmx_setzero_pr    _mm256_setzero_ps
#define gmx_store_pr      _mm256_store_ps

#define gmx_add_pr        _mm256_add_ps
#define gmx_sub_pr        _mm256_sub_ps
#define gmx_mul_pr        _mm256_mul_ps
#define gmx_madd_pr(a, b, c)   _mm256_add_ps(c, _mm256_mul_ps(a, b))
#define gmx_nmsub_pr(a, b, c)  _mm256_sub_ps(c, _mm256_mul_ps(a, b))
#define gmx_max_pr        _mm256_max_ps
#define gmx_blendzero_pr  _mm256_and_ps

#define gmx_round_pr(x)   _mm256_round_ps(x, 0x0)
#define GMX_SIMD_HAVE_FLOOR
#define gmx_floor_pr      _mm256_floor_ps

#define GMX_SIMD_HAVE_BLENDV
#define gmx_blendv_pr     _mm256_blendv_ps

static gmx_inline gmx_mm_pr gmx_cpsgn_nonneg_pr(gmx_mm_pr a, gmx_mm_pr b)
{
    gmx_mm_pr sign_mask = _mm256_set1_ps(-0.0);
    return _mm256_or_ps(_mm256_and_ps(a, sign_mask), b);
};

static gmx_inline gmx_mm_pr gmx_masknot_add_pr(gmx_mm_pb a, gmx_mm_pr b, gmx_mm_pr c)
{
    return _mm256_add_ps(b, _mm256_andnot_ps(a, c));
};

/* Less-than (we use ordered, non-signaling, but that's not required) */
#define gmx_cmplt_pr(x, y) _mm256_cmp_ps(x, y, 0x11)
#define gmx_and_pb        _mm256_and_ps
#define gmx_or_pb         _mm256_or_ps

#define gmx_anytrue_pb    _mm256_movemask_ps

#define gmx_cvttpr_epi32  _mm256_cvttps_epi32

#define gmx_rsqrt_pr      _mm256_rsqrt_ps
#define gmx_rcp_pr        _mm256_rcp_ps

#define gmx_exp_pr        gmx_mm256_exp_ps
#define gmx_sqrt_pr       gmx_mm256_sqrt_ps
#define gmx_sincos_pr     gmx_mm256_sincos_ps
#define gmx_acos_pr       gmx_mm256_acos_ps
#define gmx_atan2_pr      gmx_mm256_atan2_ps

#else /* ifndef GMX_DOUBLE */

#define GMX_SIMD_WIDTH_HERE  4

#define gmx_mm_pr  __m256d

#define gmx_mm_pb  __m256d

/* We use 128-bit integer registers because of missing 256-bit operations */
#define gmx_epi32  __m128i
#define GMX_SIMD_EPI32_WIDTH  4

#define gmx_load_pr       _mm256_load_pd
#define gmx_load1_pr(x)   _mm256_set1_pd((x)[0])
#define gmx_set1_pr       _mm256_set1_pd
#define gmx_setzero_pr    _mm256_setzero_pd
#define gmx_store_pr      _mm256_store_pd

#define gmx_add_pr        _mm256_add_pd
#define gmx_sub_pr        _mm256_sub_pd
#define gmx_mul_pr        _mm256_mul_pd
#define gmx_madd_pr(a, b, c)   _mm256_add_pd(c, _mm256_mul_pd(a, b))
#define gmx_nmsub_pr(a, b, c)  _mm256_sub_pd(c, _mm256_mul_pd(a, b))
#define gmx_max_pr        _mm256_max_pd
#define gmx_blendzero_pr  _mm256_and_pd

#define gmx_round_pr(x)   _mm256_round_pd(x, 0x0)
#define GMX_SIMD_HAVE_FLOOR
#define gmx_floor_pr      _mm256_floor_pd

#define GMX_SIMD_HAVE_BLENDV
#define gmx_blendv_pr     _mm256_blendv_pd

static gmx_inline gmx_mm_pr gmx_cpsgn_nonneg_pr(gmx_mm_pr a, gmx_mm_pr b)
{
    gmx_mm_pr sign_mask = _mm256_set1_pd(-0.0);
    return _mm256_or_pd(_mm256_and_pd(a, sign_mask), b);
};

static gmx_inline gmx_mm_pr gmx_masknot_add_pr(gmx_mm_pb a, gmx_mm_pr b, gmx_mm_pr c)
{
    return _mm256_add_pd(b, _mm256_andnot_pd(a, c));
};

/* Less-than (we use ordered, non-signaling, but that's not required) */
#define gmx_cmplt_pr(x, y) _mm256_cmp_pd(x, y, 0x11)

#define gmx_and_pb        _mm256_and_pd
#define gmx_or_pb         _mm256_or_pd

#define gmx_anytrue_pb    _mm256_movemask_pd

#define gmx_cvttpr_epi32  _mm256_cvttpd_epi32

#define gmx_rsqrt_pr(r)   _mm256_cvtps_pd(_mm_rsqrt_ps(_mm256_cvtpd_ps(r)))
#define gmx_rcp_pr(r)     _mm256_cvtps_pd(_mm_rcp_ps(_mm256_cvtpd_ps(r)))

#define gmx_exp_pr        gmx_mm256_exp_pd
#define gmx_sqrt_pr       gmx_mm256_sqrt_pd
#define gmx_sincos_pr     gmx_mm256_sincos_pd
#define gmx_acos_pr       gmx_mm256_acos_pd
#define gmx_atan2_pr      gmx_mm256_atan2_pd

#endif /* ifndef GMX_DOUBLE */

#endif /* 128- or 256-bit x86 SIMD */

#endif /* GMX_X86_SSE2 */

#endif /* GMX_TARGET_X86 */

#ifdef GMX_CPU_ACCELERATION_IBM_QPX

/* This hack works on the compilers that can reach this code. A real
   solution with broader scope will be proposed in master branch. */
#define gmx_always_inline __attribute__((always_inline))

/* This is for the A2 core on BlueGene/Q that supports IBM's QPX
   vector built-in functions */
#define GMX_HAVE_SIMD_MACROS
#ifdef __clang__
#include <qpxmath.h>
#else
#include "mass_simd.h"
#endif

/* No need to version the code by the precision, because the QPX AXU
   extends to and truncates from double precision for free. */

#define GMX_SIMD_WIDTH_HERE  4
typedef vector4double gmx_mm_pr;
typedef vector4double gmx_mm_pb;
typedef vector4double gmx_epi32;
#define GMX_SIMD_EPI32_WIDTH  4

static gmx_inline gmx_mm_pr gmx_always_inline gmx_load_pr(const real *a)
{
#ifdef NDEBUG
    return vec_ld(0, (real *) a);
#else
    return vec_lda(0, (real *) a);
#endif
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_load1_pr(const real *a)
{
    return vec_splats(*a);
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_set1_pr(real a)
{
    return vec_splats(a);
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_setzero_pr()
{
    return vec_splats(0.0);
}

static gmx_inline void gmx_always_inline gmx_store_pr(real *a, gmx_mm_pr b)
{
#ifdef NDEBUG
    vec_st(b, 0, a);
#else
    vec_sta(b, 0, a);
#endif
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_add_pr(gmx_mm_pr a, gmx_mm_pr b)
{
    return vec_add(a, b);
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_sub_pr(gmx_mm_pr a, gmx_mm_pr b)
{
    return vec_sub(a, b);
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_mul_pr(gmx_mm_pr a, gmx_mm_pr b)
{
    return vec_mul(a, b);
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_madd_pr(gmx_mm_pr a, gmx_mm_pr b, gmx_mm_pr c)
{
    return vec_madd(a, b, c);
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_nmsub_pr(gmx_mm_pr a, gmx_mm_pr b, gmx_mm_pr c)
{
    return vec_nmsub(a, b, c);
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_max_pr(gmx_mm_pr a, gmx_mm_pr b)
{
    return vec_sel(b, a, vec_sub(a, b));
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_blendzero_pr(gmx_mm_pr a, gmx_mm_pr b)
{
    return vec_sel(gmx_setzero_pr(), a, b);
}

static gmx_inline gmx_mm_pb gmx_always_inline gmx_cmplt_pr(gmx_mm_pr a, gmx_mm_pr b)
{
    return vec_cmplt(a, b);
}

static gmx_inline gmx_mm_pb gmx_always_inline gmx_and_pb(gmx_mm_pb a, gmx_mm_pb b)
{
    return vec_and(a, b);
}

static gmx_inline gmx_mm_pb gmx_always_inline gmx_or_pb(gmx_mm_pb a, gmx_mm_pb b)
{
    return vec_or(a, b);
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_round_pr(gmx_mm_pr a)
{
    return vec_round(a);
}

#define GMX_SIMD_HAVE_FLOOR
static gmx_inline gmx_mm_pr gmx_always_inline gmx_floor_pr(gmx_mm_pr a)
{
    return vec_floor(a);
}

#define GMX_SIMD_HAVE_BLENDV
static gmx_inline gmx_mm_pr gmx_always_inline gmx_blendv_pr(gmx_mm_pr a, gmx_mm_pr b, gmx_mm_pr c)
{
    return vec_sel(b, a, gmx_cmplt_pr(gmx_setzero_pr(), c));
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_cpsgn_nonneg_pr(gmx_mm_pr a, gmx_mm_pr b)
{
    return vec_cpsgn(a, b);
};

static gmx_inline gmx_mm_pr gmx_always_inline gmx_masknot_add_pr(gmx_mm_pb a, gmx_mm_pr b, gmx_mm_pr c)
{
    return vec_add(b, vec_sel(c, gmx_setzero_pr(), a));
};

static gmx_inline gmx_bool gmx_always_inline
GMX_SIMD_IS_TRUE(real x)
{
    return x >= 0.0;
}

static gmx_inline gmx_epi32 gmx_always_inline gmx_cvttpr_epi32(gmx_mm_pr a)
{
    return vec_ctiwuz(a);
}
/* Don't want this, we have floor */
/* #define gmx_cvtepi32_pr   vec_cvtepi32 */

/* A2 core on BG/Q delivers relative error of 2^-14, whereas Power ISA
   Architecture only promises 2^-8. So probably no need for
   Newton-Raphson iterates at single or double. */
static gmx_inline gmx_mm_pr gmx_always_inline gmx_rsqrt_pr(gmx_mm_pr a)
{
    return vec_rsqrte(a);
}

/* A2 core on BG/Q delivers relative error of 2^-14, whereas Power ISA
   Architecture only promises 2^-5. So probably no need for
   Newton-Raphson iterates at single or double. */
static gmx_inline gmx_mm_pr gmx_always_inline gmx_rcp_pr(gmx_mm_pr a)
{
    return vec_re(a);
}

/* Note that here, and below, we use the built-in SLEEF port when
   compiling on BlueGene/Q with clang */

#define GMX_SIMD_HAVE_EXP
static gmx_inline gmx_mm_pr gmx_always_inline gmx_exp_pr(gmx_mm_pr a)
{
#ifdef __clang__
#ifndef GMX_DOUBLE
    return xexpf(a);
#else
    return xexp(a);
#endif
#else
#ifndef GMX_DOUBLE
    return expf4(a);
#else
    return expd4(a);
#endif
#endif
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_sqrt_pr(gmx_mm_pr a)
{
#ifdef NDEBUG
    return vec_swsqrt_nochk(a);
#else
    return vec_swsqrt(a);
#endif
}

#define GMX_SIMD_HAVE_TRIGONOMETRIC
static gmx_inline int gmx_always_inline gmx_sincos_pr(gmx_mm_pr a, gmx_mm_pr *b, gmx_mm_pr *c)
{
#ifdef __clang__
#ifndef GMX_DOUBLE
    xsincosf(a, b, c);
#else
    xsincos(a, b, c);
#endif
#else
#ifndef GMX_DOUBLE
    sincosf4(a, b, c);
#else
    sincosd4(a, b, c);
#endif
#endif
    return 1;
}

static gmx_inline gmx_mm_pr gmx_always_inline gmx_acos_pr(gmx_mm_pr a)
{
#ifdef __clang__
#ifndef GMX_DOUBLE
    return xacosf(a);
#else
    return xacos(a);
#endif
#else
#ifndef GMX_DOUBLE
    return acosf4(a);
#else
    return acosd4(a);
#endif
#endif
}

/* NB The order of parameters here is correct; the
   documentation of atan2[df]4 in SIMD MASS is wrong. */
static gmx_inline gmx_mm_pr gmx_always_inline gmx_atan2_pr(gmx_mm_pr a, gmx_mm_pr b)
{
#ifdef __clang__
#ifndef GMX_DOUBLE
    return xatan2f(a, b);
#else
    return xatan2(a, b);
#endif
#else
#ifndef GMX_DOUBLE
    return atan2f4(a, b);
#else
    return atan2d4(a, b);
#endif
#endif
}

static gmx_inline int gmx_always_inline
gmx_anytrue_pb(gmx_mm_pb a)
{
    /* The "anytrue" is done solely on the QPX AXU (which is the only
       available FPU). This is awkward, because pretty much no
       "horizontal" SIMD-vector operations exist, unlike x86 where
       SSE4.1 added various kinds of horizontal operations. So we have
       to make do with shifting vector elements and operating on the
       results. This makes for lots of data dependency, but the main
       alternative of storing to memory and reloading is not going to
       help, either. OpenMP over 2 or 4 hardware threads per core will
       hide much of the latency from the data dependency. The
       vec_extract() lets the compiler correctly use a floating-point
       comparison on the zeroth vector element, which avoids needing
       memory at all.
     */
    gmx_mm_pb vec_shifted_left_0 = a;
    gmx_mm_pb vec_shifted_left_1 = vec_sldw(a, a, 1);
    gmx_mm_pb vec_shifted_left_2 = vec_sldw(a, a, 2);
    gmx_mm_pb vec_shifted_left_3 = vec_sldw(a, a, 3);

    gmx_mm_pb vec_return = vec_or(vec_or(vec_shifted_left_2, vec_shifted_left_3),
                                  vec_or(vec_shifted_left_0, vec_shifted_left_1));
    return (0.0 < vec_extract(vec_return, 0));
};

#undef gmx_always_inline

#endif /* GMX_CPU_ACCELERATION_IBM_QPX */

#ifdef GMX_HAVE_SIMD_MACROS
/* Generic functions to extract a SIMD aligned pointer from a pointer x.
 * x should have at least GMX_SIMD_WIDTH_HERE elements extra compared
 * to how many you want to use, to avoid indexing outside the aligned region.
 */

static gmx_inline real *
gmx_simd_align_real(const real *x)
{
    return (real *)(((size_t)((x)+GMX_SIMD_WIDTH_HERE)) & (~((size_t)(GMX_SIMD_WIDTH_HERE*sizeof(real)-1))));
}

static gmx_inline int *
gmx_simd_align_int(const int *x)
{
    return (int  *)(((size_t)((x)+GMX_SIMD_WIDTH_HERE)) & (~((size_t)(GMX_SIMD_WIDTH_HERE*sizeof(int )-1))));
}


/* Include the math functions which only need the above macros,
 * generally these are the ones that don't need masking operations.
 */
#ifdef GMX_DOUBLE
#include "gmx_simd_math_double.h"
#else
#include "gmx_simd_math_single.h"
#endif


#endif /* GMX_HAVE_SIMD_MACROS */

#endif /* _gmx_simd_macros_h_ */