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SIMD intrinsics interface (simd)
+ Collaboration diagram for SIMD intrinsics interface (simd):

Description

Provides an architecture-independent way of doing SIMD coding.

Overview of the SIMD implementation is provided in Single-instruction Multiple-data (SIMD) coding. The details are documented in gromacs/simd/simd.h and the reference implementation impl_reference.h.

Author
Erik Lindahl erik..nosp@m.lind.nosp@m.ahl@s.nosp@m.cili.nosp@m.felab.nosp@m..se

Namespaces

 gmx
 Generic GROMACS namespace.
 

Constant width-4 double precision SIMD types and instructions

static Simd4Double gmx_simdcall gmx::load4 (const double *m)
 Load 4 double values from aligned memory into SIMD4 variable. More...
 
static void gmx_simdcall gmx::store4 (double *m, Simd4Double a)
 Store the contents of SIMD4 double to aligned memory m. More...
 
static Simd4Double gmx_simdcall gmx::load4U (const double *m)
 Load SIMD4 double from unaligned memory. More...
 
static void gmx_simdcall gmx::store4U (double *m, Simd4Double a)
 Store SIMD4 double to unaligned memory. More...
 
static Simd4Double gmx_simdcall gmx::simd4SetZeroD ()
 Set all SIMD4 double elements to 0. More...
 
static Simd4Double gmx_simdcall gmx::operator& (Simd4Double a, Simd4Double b)
 Bitwise and for two SIMD4 double variables. More...
 
static Simd4Double gmx_simdcall gmx::andNot (Simd4Double a, Simd4Double b)
 Bitwise andnot for two SIMD4 double variables. c=(~a) & b. More...
 
static Simd4Double gmx_simdcall gmx::operator| (Simd4Double a, Simd4Double b)
 Bitwise or for two SIMD4 doubles. More...
 
static Simd4Double gmx_simdcall gmx::operator^ (Simd4Double a, Simd4Double b)
 Bitwise xor for two SIMD4 double variables. More...
 
static Simd4Double gmx_simdcall gmx::operator+ (Simd4Double a, Simd4Double b)
 Add two double SIMD4 variables. More...
 
static Simd4Double gmx_simdcall gmx::operator- (Simd4Double a, Simd4Double b)
 Subtract two SIMD4 variables. More...
 
static Simd4Double gmx_simdcall gmx::operator- (Simd4Double a)
 SIMD4 floating-point negate. More...
 
static Simd4Double gmx_simdcall gmx::operator* (Simd4Double a, Simd4Double b)
 Multiply two SIMD4 variables. More...
 
static Simd4Double gmx_simdcall gmx::fma (Simd4Double a, Simd4Double b, Simd4Double c)
 SIMD4 Fused-multiply-add. Result is a*b+c. More...
 
static Simd4Double gmx_simdcall gmx::fms (Simd4Double a, Simd4Double b, Simd4Double c)
 SIMD4 Fused-multiply-subtract. Result is a*b-c. More...
 
static Simd4Double gmx_simdcall gmx::fnma (Simd4Double a, Simd4Double b, Simd4Double c)
 SIMD4 Fused-negated-multiply-add. Result is -a*b+c. More...
 
static Simd4Double gmx_simdcall gmx::fnms (Simd4Double a, Simd4Double b, Simd4Double c)
 SIMD4 Fused-negated-multiply-subtract. Result is -a*b-c. More...
 
static Simd4Double gmx_simdcall gmx::rsqrt (Simd4Double x)
 SIMD4 1.0/sqrt(x) lookup. More...
 
static Simd4Double gmx_simdcall gmx::abs (Simd4Double a)
 SIMD4 Floating-point abs(). More...
 
static Simd4Double gmx_simdcall gmx::max (Simd4Double a, Simd4Double b)
 Set each SIMD4 element to the largest from two variables. More...
 
static Simd4Double gmx_simdcall gmx::min (Simd4Double a, Simd4Double b)
 Set each SIMD4 element to the largest from two variables. More...
 
static Simd4Double gmx_simdcall gmx::round (Simd4Double a)
 SIMD4 Round to nearest integer value (in floating-point format). More...
 
static Simd4Double gmx_simdcall gmx::trunc (Simd4Double a)
 Truncate SIMD4, i.e. round towards zero - common hardware instruction. More...
 
static double gmx_simdcall gmx::dotProduct (Simd4Double a, Simd4Double b)
 Return dot product of two double precision SIMD4 variables. More...
 
static void gmx_simdcall gmx::transpose (Simd4Double *v0, Simd4Double *v1, Simd4Double *v2, Simd4Double *v3)
 SIMD4 double transpose. More...
 
static Simd4DBool gmx_simdcall gmx::operator== (Simd4Double a, Simd4Double b)
 a==b for SIMD4 double More...
 
static Simd4DBool gmx_simdcall gmx::operator!= (Simd4Double a, Simd4Double b)
 a!=b for SIMD4 double More...
 
static Simd4DBool gmx_simdcall gmx::operator< (Simd4Double a, Simd4Double b)
 a<b for SIMD4 double More...
 
static Simd4DBool gmx_simdcall gmx::operator<= (Simd4Double a, Simd4Double b)
 a<=b for SIMD4 double. More...
 
static Simd4DBool gmx_simdcall gmx::operator&& (Simd4DBool a, Simd4DBool b)
 Logical and on single precision SIMD4 booleans. More...
 
static Simd4DBool gmx_simdcall gmx::operator|| (Simd4DBool a, Simd4DBool b)
 Logical or on single precision SIMD4 booleans. More...
 
static bool gmx_simdcall gmx::anyTrue (Simd4DBool a)
 Returns non-zero if any of the boolean in SIMD4 a is True, otherwise 0. More...
 
static Simd4Double gmx_simdcall gmx::selectByMask (Simd4Double a, Simd4DBool mask)
 Select from single precision SIMD4 variable where boolean is true. More...
 
static Simd4Double gmx_simdcall gmx::selectByNotMask (Simd4Double a, Simd4DBool mask)
 Select from single precision SIMD4 variable where boolean is false. More...
 
static Simd4Double gmx_simdcall gmx::blend (Simd4Double a, Simd4Double b, Simd4DBool sel)
 Vector-blend SIMD4 selection. More...
 
static double gmx_simdcall gmx::reduce (Simd4Double a)
 Return sum of all elements in SIMD4 double variable. More...
 

Constant width-4 single precision SIMD types and instructions

static Simd4Float gmx_simdcall gmx::load4 (const float *m)
 Load 4 float values from aligned memory into SIMD4 variable. More...
 
static void gmx_simdcall gmx::store4 (float *m, Simd4Float a)
 Store the contents of SIMD4 float to aligned memory m. More...
 
static Simd4Float gmx_simdcall gmx::load4U (const float *m)
 Load SIMD4 float from unaligned memory. More...
 
static void gmx_simdcall gmx::store4U (float *m, Simd4Float a)
 Store SIMD4 float to unaligned memory. More...
 
static Simd4Float gmx_simdcall gmx::simd4SetZeroF ()
 Set all SIMD4 float elements to 0. More...
 
static Simd4Float gmx_simdcall gmx::operator& (Simd4Float a, Simd4Float b)
 Bitwise and for two SIMD4 float variables. More...
 
static Simd4Float gmx_simdcall gmx::andNot (Simd4Float a, Simd4Float b)
 Bitwise andnot for two SIMD4 float variables. c=(~a) & b. More...
 
static Simd4Float gmx_simdcall gmx::operator| (Simd4Float a, Simd4Float b)
 Bitwise or for two SIMD4 floats. More...
 
static Simd4Float gmx_simdcall gmx::operator^ (Simd4Float a, Simd4Float b)
 Bitwise xor for two SIMD4 float variables. More...
 
static Simd4Float gmx_simdcall gmx::operator+ (Simd4Float a, Simd4Float b)
 Add two float SIMD4 variables. More...
 
static Simd4Float gmx_simdcall gmx::operator- (Simd4Float a, Simd4Float b)
 Subtract two SIMD4 variables. More...
 
static Simd4Float gmx_simdcall gmx::operator- (Simd4Float a)
 SIMD4 floating-point negate. More...
 
static Simd4Float gmx_simdcall gmx::operator* (Simd4Float a, Simd4Float b)
 Multiply two SIMD4 variables. More...
 
static Simd4Float gmx_simdcall gmx::fma (Simd4Float a, Simd4Float b, Simd4Float c)
 SIMD4 Fused-multiply-add. Result is a*b+c. More...
 
static Simd4Float gmx_simdcall gmx::fms (Simd4Float a, Simd4Float b, Simd4Float c)
 SIMD4 Fused-multiply-subtract. Result is a*b-c. More...
 
static Simd4Float gmx_simdcall gmx::fnma (Simd4Float a, Simd4Float b, Simd4Float c)
 SIMD4 Fused-negated-multiply-add. Result is -a*b+c. More...
 
static Simd4Float gmx_simdcall gmx::fnms (Simd4Float a, Simd4Float b, Simd4Float c)
 SIMD4 Fused-negated-multiply-subtract. Result is -a*b-c. More...
 
static Simd4Float gmx_simdcall gmx::rsqrt (Simd4Float x)
 SIMD4 1.0/sqrt(x) lookup. More...
 
static Simd4Float gmx_simdcall gmx::abs (Simd4Float a)
 SIMD4 Floating-point fabs(). More...
 
static Simd4Float gmx_simdcall gmx::max (Simd4Float a, Simd4Float b)
 Set each SIMD4 element to the largest from two variables. More...
 
static Simd4Float gmx_simdcall gmx::min (Simd4Float a, Simd4Float b)
 Set each SIMD4 element to the largest from two variables. More...
 
static Simd4Float gmx_simdcall gmx::round (Simd4Float a)
 SIMD4 Round to nearest integer value (in floating-point format). More...
 
static Simd4Float gmx_simdcall gmx::trunc (Simd4Float a)
 Truncate SIMD4, i.e. round towards zero - common hardware instruction. More...
 
static float gmx_simdcall gmx::dotProduct (Simd4Float a, Simd4Float b)
 Return dot product of two single precision SIMD4 variables. More...
 
static void gmx_simdcall gmx::transpose (Simd4Float *v0, Simd4Float *v1, Simd4Float *v2, Simd4Float *v3)
 SIMD4 float transpose. More...
 
static Simd4FBool gmx_simdcall gmx::operator== (Simd4Float a, Simd4Float b)
 a==b for SIMD4 float More...
 
static Simd4FBool gmx_simdcall gmx::operator!= (Simd4Float a, Simd4Float b)
 a!=b for SIMD4 float More...
 
static Simd4FBool gmx_simdcall gmx::operator< (Simd4Float a, Simd4Float b)
 a<b for SIMD4 float More...
 
static Simd4FBool gmx_simdcall gmx::operator<= (Simd4Float a, Simd4Float b)
 a<=b for SIMD4 float. More...
 
static Simd4FBool gmx_simdcall gmx::operator&& (Simd4FBool a, Simd4FBool b)
 Logical and on single precision SIMD4 booleans. More...
 
static Simd4FBool gmx_simdcall gmx::operator|| (Simd4FBool a, Simd4FBool b)
 Logical or on single precision SIMD4 booleans. More...
 
static bool gmx_simdcall gmx::anyTrue (Simd4FBool a)
 Returns non-zero if any of the boolean in SIMD4 a is True, otherwise 0. More...
 
static Simd4Float gmx_simdcall gmx::selectByMask (Simd4Float a, Simd4FBool mask)
 Select from single precision SIMD4 variable where boolean is true. More...
 
static Simd4Float gmx_simdcall gmx::selectByNotMask (Simd4Float a, Simd4FBool mask)
 Select from single precision SIMD4 variable where boolean is false. More...
 
static Simd4Float gmx_simdcall gmx::blend (Simd4Float a, Simd4Float b, Simd4FBool sel)
 Vector-blend SIMD4 selection. More...
 
static float gmx_simdcall gmx::reduce (Simd4Float a)
 Return sum of all elements in SIMD4 float variable. More...
 

SIMD predefined macros to describe high-level capabilities

These macros are used to describe the features available in default Gromacs real precision. They are set from the lower-level implementation files that have macros describing single and double precision individually, as well as the implementation details.

#define GMX_SIMD_HAVE_REAL   GMX_SIMD_HAVE_FLOAT
 1 if SimdReal is available, otherwise 0. More...
 
#define GMX_SIMD_REAL_WIDTH   GMX_SIMD_FLOAT_WIDTH
 Width of SimdReal. More...
 
#define GMX_SIMD_HAVE_INT32_EXTRACT   GMX_SIMD_HAVE_FINT32_EXTRACT
 1 if support is available for extracting elements from SimdInt32, otherwise 0 More...
 
#define GMX_SIMD_HAVE_INT32_LOGICAL   GMX_SIMD_HAVE_FINT32_LOGICAL
 1 if logical ops are supported on SimdInt32, otherwise 0. More...
 
#define GMX_SIMD_HAVE_INT32_ARITHMETICS   GMX_SIMD_HAVE_FINT32_ARITHMETICS
 1 if arithmetic ops are supported on SimdInt32, otherwise 0. More...
 
#define GMX_SIMD_HAVE_GATHER_LOADU_BYSIMDINT_TRANSPOSE_REAL   GMX_SIMD_HAVE_GATHER_LOADU_BYSIMDINT_TRANSPOSE_FLOAT
 1 if gmx::simdGatherLoadUBySimdIntTranspose is present, otherwise 0 More...
 
#define GMX_SIMD_HAVE_HSIMD_UTIL_REAL   GMX_SIMD_HAVE_HSIMD_UTIL_FLOAT
 1 if real half-register load/store/reduce utils present, otherwise 0 More...
 
#define GMX_SIMD4_HAVE_REAL   GMX_SIMD4_HAVE_FLOAT
 1 if Simd4Real is available, otherwise 0. More...
 

Single precision SIMD math functions

Note
In most cases you should use the real-precision functions instead.
static SimdFloat gmx_simdcall gmx::copysign (SimdFloat x, SimdFloat y)
 Composes floating point value with the magnitude of x and the sign of y. More...
 
static SimdFloat gmx_simdcall gmx::rsqrtIter (SimdFloat lu, SimdFloat x)
 Perform one Newton-Raphson iteration to improve 1/sqrt(x) for SIMD float. More...
 
static SimdFloat gmx_simdcall gmx::invsqrt (SimdFloat x)
 Calculate 1/sqrt(x) for SIMD float. More...
 
static void gmx_simdcall gmx::invsqrtPair (SimdFloat x0, SimdFloat x1, SimdFloat *out0, SimdFloat *out1)
 Calculate 1/sqrt(x) for two SIMD floats. More...
 
static SimdFloat gmx_simdcall gmx::rcpIter (SimdFloat lu, SimdFloat x)
 Perform one Newton-Raphson iteration to improve 1/x for SIMD float. More...
 
static SimdFloat gmx_simdcall gmx::inv (SimdFloat x)
 Calculate 1/x for SIMD float. More...
 
static SimdFloat gmx_simdcall gmx::operator/ (SimdFloat nom, SimdFloat denom)
 Division for SIMD floats. More...
 
static SimdFloat gmx::maskzInvsqrt (SimdFloat x, SimdFBool m)
 Calculate 1/sqrt(x) for masked entries of SIMD float. More...
 
static SimdFloat gmx_simdcall gmx::maskzInv (SimdFloat x, SimdFBool m)
 Calculate 1/x for SIMD float, masked version. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::sqrt (SimdFloat x)
 Calculate sqrt(x) for SIMD floats. More...
 
static SimdFloat gmx_simdcall gmx::cbrt (SimdFloat x)
 Cube root for SIMD floats. More...
 
static SimdFloat gmx_simdcall gmx::invcbrt (SimdFloat x)
 Inverse cube root for SIMD floats. More...
 
static SimdFloat gmx_simdcall gmx::log2 (SimdFloat x)
 SIMD float log2(x). This is the base-2 logarithm. More...
 
static SimdFloat gmx_simdcall gmx::log (SimdFloat x)
 SIMD float log(x). This is the natural logarithm. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::exp2 (SimdFloat x)
 SIMD float 2^x. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::exp (SimdFloat x)
 SIMD float exp(x). More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::pow (SimdFloat x, SimdFloat y)
 SIMD float pow(x,y) More...
 
static SimdFloat gmx_simdcall gmx::erf (SimdFloat x)
 SIMD float erf(x). More...
 
static SimdFloat gmx_simdcall gmx::erfc (SimdFloat x)
 SIMD float erfc(x). More...
 
static void gmx_simdcall gmx::sincos (SimdFloat x, SimdFloat *sinval, SimdFloat *cosval)
 SIMD float sin & cos. More...
 
static SimdFloat gmx_simdcall gmx::sin (SimdFloat x)
 SIMD float sin(x). More...
 
static SimdFloat gmx_simdcall gmx::cos (SimdFloat x)
 SIMD float cos(x). More...
 
static SimdFloat gmx_simdcall gmx::tan (SimdFloat x)
 SIMD float tan(x). More...
 
static SimdFloat gmx_simdcall gmx::asin (SimdFloat x)
 SIMD float asin(x). More...
 
static SimdFloat gmx_simdcall gmx::acos (SimdFloat x)
 SIMD float acos(x). More...
 
static SimdFloat gmx_simdcall gmx::atan (SimdFloat x)
 SIMD float asin(x). More...
 
static SimdFloat gmx_simdcall gmx::atan2 (SimdFloat y, SimdFloat x)
 SIMD float atan2(y,x). More...
 
static SimdFloat gmx_simdcall gmx::pmeForceCorrection (SimdFloat z2)
 Calculate the force correction due to PME analytically in SIMD float. More...
 
static SimdFloat gmx_simdcall gmx::pmePotentialCorrection (SimdFloat z2)
 Calculate the potential correction due to PME analytically in SIMD float. More...
 

Double precision SIMD math functions

Note
In most cases you should use the real-precision functions instead.
static SimdDouble gmx_simdcall gmx::copysign (SimdDouble x, SimdDouble y)
 Composes floating point value with the magnitude of x and the sign of y. More...
 
static SimdDouble gmx_simdcall gmx::rsqrtIter (SimdDouble lu, SimdDouble x)
 Perform one Newton-Raphson iteration to improve 1/sqrt(x) for SIMD double. More...
 
static SimdDouble gmx_simdcall gmx::invsqrt (SimdDouble x)
 Calculate 1/sqrt(x) for SIMD double. More...
 
static void gmx_simdcall gmx::invsqrtPair (SimdDouble x0, SimdDouble x1, SimdDouble *out0, SimdDouble *out1)
 Calculate 1/sqrt(x) for two SIMD doubles. More...
 
static SimdDouble gmx_simdcall gmx::rcpIter (SimdDouble lu, SimdDouble x)
 Perform one Newton-Raphson iteration to improve 1/x for SIMD double. More...
 
static SimdDouble gmx_simdcall gmx::inv (SimdDouble x)
 Calculate 1/x for SIMD double. More...
 
static SimdDouble gmx_simdcall gmx::operator/ (SimdDouble nom, SimdDouble denom)
 Division for SIMD doubles. More...
 
static SimdDouble gmx::maskzInvsqrt (SimdDouble x, SimdDBool m)
 Calculate 1/sqrt(x) for masked entries of SIMD double. More...
 
static SimdDouble gmx_simdcall gmx::maskzInv (SimdDouble x, SimdDBool m)
 Calculate 1/x for SIMD double, masked version. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::sqrt (SimdDouble x)
 Calculate sqrt(x) for SIMD doubles. More...
 
static SimdDouble gmx_simdcall gmx::cbrt (SimdDouble x)
 Cube root for SIMD doubles. More...
 
static SimdDouble gmx_simdcall gmx::invcbrt (SimdDouble x)
 Inverse cube root for SIMD doubles. More...
 
static SimdDouble gmx_simdcall gmx::log2 (SimdDouble x)
 SIMD double log2(x). This is the base-2 logarithm. More...
 
static SimdDouble gmx_simdcall gmx::log (SimdDouble x)
 SIMD double log(x). This is the natural logarithm. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::exp2 (SimdDouble x)
 SIMD double 2^x. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::exp (SimdDouble x)
 SIMD double exp(x). More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::pow (SimdDouble x, SimdDouble y)
 SIMD double pow(x,y) More...
 
static SimdDouble gmx_simdcall gmx::erf (SimdDouble x)
 SIMD double erf(x). More...
 
static SimdDouble gmx_simdcall gmx::erfc (SimdDouble x)
 SIMD double erfc(x). More...
 
static void gmx_simdcall gmx::sincos (SimdDouble x, SimdDouble *sinval, SimdDouble *cosval)
 SIMD double sin & cos. More...
 
static SimdDouble gmx_simdcall gmx::sin (SimdDouble x)
 SIMD double sin(x). More...
 
static SimdDouble gmx_simdcall gmx::cos (SimdDouble x)
 SIMD double cos(x). More...
 
static SimdDouble gmx_simdcall gmx::tan (SimdDouble x)
 SIMD double tan(x). More...
 
static SimdDouble gmx_simdcall gmx::asin (SimdDouble x)
 SIMD double asin(x). More...
 
static SimdDouble gmx_simdcall gmx::acos (SimdDouble x)
 SIMD double acos(x). More...
 
static SimdDouble gmx_simdcall gmx::atan (SimdDouble x)
 SIMD double asin(x). More...
 
static SimdDouble gmx_simdcall gmx::atan2 (SimdDouble y, SimdDouble x)
 SIMD double atan2(y,x). More...
 
static SimdDouble gmx_simdcall gmx::pmeForceCorrection (SimdDouble z2)
 Calculate the force correction due to PME analytically in SIMD double. More...
 
static SimdDouble gmx_simdcall gmx::pmePotentialCorrection (SimdDouble z2)
 Calculate the potential correction due to PME analytically in SIMD double. More...
 

SIMD math functions for double prec. data, single prec. accuracy

Note
In some cases we do not need full double accuracy of individual SIMD math functions, although the data is stored in double precision SIMD registers. This might be the case for special algorithms, or if the architecture does not support single precision. Since the full double precision evaluation of math functions typically require much more expensive polynomial approximations these functions implement the algorithms used in the single precision SIMD math functions, but they operate on double precision SIMD variables.
static SimdDouble gmx_simdcall gmx::invsqrtSingleAccuracy (SimdDouble x)
 Calculate 1/sqrt(x) for SIMD double, but in single accuracy. More...
 
static SimdDouble gmx::maskzInvsqrtSingleAccuracy (SimdDouble x, SimdDBool m)
 1/sqrt(x) for masked-in entries of SIMD double, but in single accuracy. More...
 
static void gmx_simdcall gmx::invsqrtPairSingleAccuracy (SimdDouble x0, SimdDouble x1, SimdDouble *out0, SimdDouble *out1)
 Calculate 1/sqrt(x) for two SIMD doubles, but single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::invSingleAccuracy (SimdDouble x)
 Calculate 1/x for SIMD double, but in single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::maskzInvSingleAccuracy (SimdDouble x, SimdDBool m)
 1/x for masked entries of SIMD double, single accuracy. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::sqrtSingleAccuracy (SimdDouble x)
 Calculate sqrt(x) (correct for 0.0) for SIMD double, with single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::cbrtSingleAccuracy (SimdDouble x)
 Cube root for SIMD doubles, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::invcbrtSingleAccuracy (SimdDouble x)
 Inverse cube root for SIMD doubles, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::log2SingleAccuracy (SimdDouble x)
 SIMD log2(x). Double precision SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::logSingleAccuracy (SimdDouble x)
 SIMD log(x). Double precision SIMD data, single accuracy. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::exp2SingleAccuracy (SimdDouble x)
 SIMD 2^x. Double precision SIMD, single accuracy. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::expSingleAccuracy (SimdDouble x)
 SIMD exp(x). Double precision SIMD, single accuracy. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::powSingleAccuracy (SimdDouble x, SimdDouble y)
 SIMD pow(x,y). Double precision SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::erfSingleAccuracy (SimdDouble x)
 SIMD erf(x). Double precision SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::erfcSingleAccuracy (SimdDouble x)
 SIMD erfc(x). Double precision SIMD data, single accuracy. More...
 
static void gmx_simdcall gmx::sinCosSingleAccuracy (SimdDouble x, SimdDouble *sinval, SimdDouble *cosval)
 SIMD sin & cos. Double precision SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::sinSingleAccuracy (SimdDouble x)
 SIMD sin(x). Double precision SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::cosSingleAccuracy (SimdDouble x)
 SIMD cos(x). Double precision SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::tanSingleAccuracy (SimdDouble x)
 SIMD tan(x). Double precision SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::asinSingleAccuracy (SimdDouble x)
 SIMD asin(x). Double precision SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::acosSingleAccuracy (SimdDouble x)
 SIMD acos(x). Double precision SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::atanSingleAccuracy (SimdDouble x)
 SIMD asin(x). Double precision SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::atan2SingleAccuracy (SimdDouble y, SimdDouble x)
 SIMD atan2(y,x). Double precision SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::pmeForceCorrectionSingleAccuracy (SimdDouble z2)
 Analytical PME force correction, double SIMD data, single accuracy. More...
 
static SimdDouble gmx_simdcall gmx::pmePotentialCorrectionSingleAccuracy (SimdDouble z2)
 Analytical PME potential correction, double SIMD data, single accuracy. More...
 

SIMD4 math functions

Note
Only a subset of the math functions are implemented for SIMD4.
static Simd4Float gmx_simdcall gmx::rsqrtIter (Simd4Float lu, Simd4Float x)
 Perform one Newton-Raphson iteration to improve 1/sqrt(x) for SIMD4 float. More...
 
static Simd4Float gmx_simdcall gmx::invsqrt (Simd4Float x)
 Calculate 1/sqrt(x) for SIMD4 float. More...
 
static Simd4Double gmx_simdcall gmx::rsqrtIter (Simd4Double lu, Simd4Double x)
 Perform one Newton-Raphson iteration to improve 1/sqrt(x) for SIMD4 double. More...
 
static Simd4Double gmx_simdcall gmx::invsqrt (Simd4Double x)
 Calculate 1/sqrt(x) for SIMD4 double. More...
 
static Simd4Double gmx_simdcall gmx::invsqrtSingleAccuracy (Simd4Double x)
 Calculate 1/sqrt(x) for SIMD4 double, but in single accuracy. More...
 

Classes

class  gmx::Simd4Double
 SIMD4 double type. More...
 
class  gmx::Simd4DBool
 SIMD4 variable type to use for logical comparisons on doubles. More...
 
class  gmx::Simd4Float
 SIMD4 float type. More...
 
class  gmx::Simd4FBool
 SIMD4 variable type to use for logical comparisons on floats. More...
 
class  gmx::SimdDouble
 Double SIMD variable. Available if GMX_SIMD_HAVE_DOUBLE is 1. More...
 
class  gmx::SimdDInt32
 Integer SIMD variable type to use for conversions to/from double. More...
 
class  gmx::SimdDBool
 Boolean type for double SIMD data. More...
 
class  gmx::SimdDIBool
 Boolean type for integer datatypes corresponding to double SIMD. More...
 
class  gmx::SimdFloat
 Float SIMD variable. Available if GMX_SIMD_HAVE_FLOAT is 1. More...
 
class  gmx::SimdFInt32
 Integer SIMD variable type to use for conversions to/from float. More...
 
class  gmx::SimdFBool
 Boolean type for float SIMD data. More...
 
class  gmx::SimdFIBool
 Boolean type for integer datatypes corresponding to float SIMD. More...
 
class  gmx::test::SimdBaseTest
 Base class for SIMD test fixtures. More...
 
class  gmx::test::SimdTest
 Test fixture for SIMD tests. More...
 
class  gmx::test::Simd4Test
 Test fixture for SIMD4 tests - contains test settings. More...
 
class  gmx::test::anonymous_namespace{simd_floatingpoint_util.cpp}::SimdFloatingpointUtilTest
 Test fixture for higher-level floating-point utility functions. More...
 

Macros

#define GMX_EXPECT_SIMD_REAL_EQ(ref, tst)   EXPECT_PRED_FORMAT2(compareSimdEq, ref, tst)
 Test if a SIMD real is bitwise identical to reference SIMD value.
 
#define GMX_EXPECT_SIMD_EQ(ref, tst)   EXPECT_PRED_FORMAT2(compareSimdEq, ref, tst)
 Test if a SIMD is bitwise identical to reference SIMD value.
 
#define GMX_EXPECT_SIMD_REAL_NEAR(ref, tst)   EXPECT_PRED_FORMAT2(compareSimdRealUlp, ref, tst)
 Test if a SIMD real is within tolerance of reference SIMD value.
 
#define GMX_EXPECT_SIMD_INT_EQ(ref, tst)   EXPECT_PRED_FORMAT2(compareSimdEq, ref, tst)
 Macro that checks SIMD integer expression against SIMD or reference int. More...
 
#define GMX_EXPECT_SIMD4_REAL_EQ(ref, tst)   EXPECT_PRED_FORMAT2(compareSimd4RealEq, ref, tst)
 Test if a SIMD4 real is bitwise identical to reference SIMD4 value.
 
#define GMX_EXPECT_SIMD4_REAL_NEAR(ref, tst)   EXPECT_PRED_FORMAT2(compareSimd4RealUlp, ref, tst)
 Test if a SIMD4 real is within tolerance of reference SIMD4 value.
 
#define GMX_EXPECT_SIMD_FUNC_NEAR(refFunc, tstFunc, compareSettings)   EXPECT_PRED_FORMAT3(compareSimdMathFunction, refFunc, tstFunc, compareSettings)
 Test approximate equality of SIMD vs reference version of a function. More...
 

Typedefs

typedef Simd4Test gmx::test::anonymous_namespace{simd4_floatingpoint.cpp}::Simd4FloatingpointTest
 Test fixture for SIMD4 floating-point operations (identical to the SIMD4 Simd4Test)
 
typedef Simd4Test gmx::test::anonymous_namespace{simd4_vector_operations.cpp}::Simd4VectorOperationsTest
 Test fixture for SIMD4 vector operations (identical to the SIMD4 Simd4Test)
 
typedef SimdTest gmx::test::anonymous_namespace{simd_floatingpoint.cpp}::SimdFloatingpointTest
 Test fixture for floating-point tests (identical to the generic SimdTest)
 
typedef SimdTest gmx::test::anonymous_namespace{simd_integer.cpp}::SimdIntegerTest
 Test fixture for integer tests (identical to the generic SimdTest)
 
typedef SimdTest gmx::test::anonymous_namespace{simd_vector_operations.cpp}::SimdVectorOperationsTest
 Test fixture for vector operations tests (identical to the generic SimdTest) More...
 

Functions

template<int align>
static void gmx_simdcall gmx::gatherLoadTranspose (const double *base, const std::int32_t offset[], SimdDouble *v0, SimdDouble *v1, SimdDouble *v2, SimdDouble *v3)
 Load 4 consecutive double from each of GMX_SIMD_DOUBLE_WIDTH offsets, and transpose into 4 SIMD double variables. More...
 
template<int align>
static void gmx_simdcall gmx::gatherLoadTranspose (const double *base, const std::int32_t offset[], SimdDouble *v0, SimdDouble *v1)
 Load 2 consecutive double from each of GMX_SIMD_DOUBLE_WIDTH offsets, and transpose into 2 SIMD double variables. More...
 
template<int align>
static void gmx_simdcall gmx::gatherLoadUTranspose (const double *base, const std::int32_t offset[], SimdDouble *v0, SimdDouble *v1, SimdDouble *v2)
 Load 3 consecutive doubles from each of GMX_SIMD_DOUBLE_WIDTH offsets, and transpose into 3 SIMD double variables. More...
 
template<int align>
static void gmx_simdcall gmx::transposeScatterStoreU (double *base, const std::int32_t offset[], SimdDouble v0, SimdDouble v1, SimdDouble v2)
 Transpose and store 3 SIMD doubles to 3 consecutive addresses at GMX_SIMD_DOUBLE_WIDTH offsets. More...
 
template<int align>
static void gmx_simdcall gmx::transposeScatterIncrU (double *base, const std::int32_t offset[], SimdDouble v0, SimdDouble v1, SimdDouble v2)
 Transpose and add 3 SIMD doubles to 3 consecutive addresses at GMX_SIMD_DOUBLE_WIDTH offsets. More...
 
template<int align>
static void gmx_simdcall gmx::transposeScatterDecrU (double *base, const std::int32_t offset[], SimdDouble v0, SimdDouble v1, SimdDouble v2)
 Transpose and subtract 3 SIMD doubles to 3 consecutive addresses at GMX_SIMD_DOUBLE_WIDTH offsets. More...
 
static void gmx_simdcall gmx::expandScalarsToTriplets (SimdDouble scalar, SimdDouble *triplets0, SimdDouble *triplets1, SimdDouble *triplets2)
 Expand each element of double SIMD variable into three identical consecutive elements in three SIMD outputs. More...
 
template<int align>
static void gmx_simdcall gmx::gatherLoadBySimdIntTranspose (const double *base, SimdDInt32 offset, SimdDouble *v0, SimdDouble *v1, SimdDouble *v2, SimdDouble *v3)
 Load 4 consecutive doubles from each of GMX_SIMD_DOUBLE_WIDTH offsets specified by a SIMD integer, transpose into 4 SIMD double variables. More...
 
template<int align>
static void gmx_simdcall gmx::gatherLoadUBySimdIntTranspose (const double *base, SimdDInt32 offset, SimdDouble *v0, SimdDouble *v1)
 Load 2 consecutive doubles from each of GMX_SIMD_DOUBLE_WIDTH offsets (unaligned) specified by SIMD integer, transpose into 2 SIMD doubles. More...
 
template<int align>
static void gmx_simdcall gmx::gatherLoadBySimdIntTranspose (const double *base, SimdDInt32 offset, SimdDouble *v0, SimdDouble *v1)
 Load 2 consecutive doubles from each of GMX_SIMD_DOUBLE_WIDTH offsets specified by a SIMD integer, transpose into 2 SIMD double variables. More...
 
static double gmx_simdcall gmx::reduceIncr4ReturnSum (double *m, SimdDouble v0, SimdDouble v1, SimdDouble v2, SimdDouble v3)
 Reduce each of four SIMD doubles, add those values to four consecutive doubles in memory, return sum. More...
 
template<int align>
static void gmx_simdcall gmx::gatherLoadTranspose (const float *base, const std::int32_t offset[], SimdFloat *v0, SimdFloat *v1, SimdFloat *v2, SimdFloat *v3)
 Load 4 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets, and transpose into 4 SIMD float variables. More...
 
template<int align>
static void gmx_simdcall gmx::gatherLoadTranspose (const float *base, const std::int32_t offset[], SimdFloat *v0, SimdFloat *v1)
 Load 2 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets, and transpose into 2 SIMD float variables. More...
 
template<int align>
static void gmx_simdcall gmx::gatherLoadUTranspose (const float *base, const std::int32_t offset[], SimdFloat *v0, SimdFloat *v1, SimdFloat *v2)
 Load 3 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets, and transpose into 3 SIMD float variables. More...
 
template<int align>
static void gmx_simdcall gmx::transposeScatterStoreU (float *base, const std::int32_t offset[], SimdFloat v0, SimdFloat v1, SimdFloat v2)
 Transpose and store 3 SIMD floats to 3 consecutive addresses at GMX_SIMD_FLOAT_WIDTH offsets. More...
 
template<int align>
static void gmx_simdcall gmx::transposeScatterIncrU (float *base, const std::int32_t offset[], SimdFloat v0, SimdFloat v1, SimdFloat v2)
 Transpose and add 3 SIMD floats to 3 consecutive addresses at GMX_SIMD_FLOAT_WIDTH offsets. More...
 
template<int align>
static void gmx_simdcall gmx::transposeScatterDecrU (float *base, const std::int32_t offset[], SimdFloat v0, SimdFloat v1, SimdFloat v2)
 Transpose and subtract 3 SIMD floats to 3 consecutive addresses at GMX_SIMD_FLOAT_WIDTH offsets. More...
 
static void gmx_simdcall gmx::expandScalarsToTriplets (SimdFloat scalar, SimdFloat *triplets0, SimdFloat *triplets1, SimdFloat *triplets2)
 Expand each element of float SIMD variable into three identical consecutive elements in three SIMD outputs. More...
 
template<int align>
static void gmx_simdcall gmx::gatherLoadBySimdIntTranspose (const float *base, SimdFInt32 offset, SimdFloat *v0, SimdFloat *v1, SimdFloat *v2, SimdFloat *v3)
 Load 4 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets specified by a SIMD integer, transpose into 4 SIMD float variables. More...
 
template<int align>
static void gmx_simdcall gmx::gatherLoadUBySimdIntTranspose (const float *base, SimdFInt32 offset, SimdFloat *v0, SimdFloat *v1)
 Load 2 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets (unaligned) specified by SIMD integer, transpose into 2 SIMD floats. More...
 
template<int align>
static void gmx_simdcall gmx::gatherLoadBySimdIntTranspose (const float *base, SimdFInt32 offset, SimdFloat *v0, SimdFloat *v1)
 Load 2 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets specified by a SIMD integer, transpose into 2 SIMD float variables. More...
 
static float gmx_simdcall gmx::reduceIncr4ReturnSum (float *m, SimdFloat v0, SimdFloat v1, SimdFloat v2, SimdFloat v3)
 Reduce each of four SIMD floats, add those values to four consecutive floats in memory, return sum. More...
 
static SimdFloat gmx_simdcall gmx::invsqrtSingleAccuracy (SimdFloat x)
 Calculate 1/sqrt(x) for SIMD float, only targeting single accuracy. More...
 
static SimdFloat gmx::maskzInvsqrtSingleAccuracy (SimdFloat x, SimdFBool m)
 Calculate 1/sqrt(x) for masked SIMD floats, only targeting single accuracy. More...
 
static void gmx_simdcall gmx::invsqrtPairSingleAccuracy (SimdFloat x0, SimdFloat x1, SimdFloat *out0, SimdFloat *out1)
 Calculate 1/sqrt(x) for two SIMD floats, only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::invSingleAccuracy (SimdFloat x)
 Calculate 1/x for SIMD float, only targeting single accuracy. More...
 
static SimdFloat gmx::maskzInvSingleAccuracy (SimdFloat x, SimdFBool m)
 Calculate 1/x for masked SIMD floats, only targeting single accuracy. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::sqrtSingleAccuracy (SimdFloat x)
 Calculate sqrt(x) for SIMD float, always targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::cbrtSingleAccuracy (SimdFloat x)
 Calculate cbrt(x) for SIMD float, always targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::invcbrtSingleAccuracy (SimdFloat x)
 Calculate 1/cbrt(x) for SIMD float, always targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::log2SingleAccuracy (SimdFloat x)
 SIMD float log2(x), only targeting single accuracy. This is the base-2 logarithm. More...
 
static SimdFloat gmx_simdcall gmx::logSingleAccuracy (SimdFloat x)
 SIMD float log(x), only targeting single accuracy. This is the natural logarithm. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::exp2SingleAccuracy (SimdFloat x)
 SIMD float 2^x, only targeting single accuracy. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::expSingleAccuracy (SimdFloat x)
 SIMD float e^x, only targeting single accuracy. More...
 
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::powSingleAccuracy (SimdFloat x, SimdFloat y)
 SIMD pow(x,y), only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::erfSingleAccuracy (SimdFloat x)
 SIMD float erf(x), only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::erfcSingleAccuracy (SimdFloat x)
 SIMD float erfc(x), only targeting single accuracy. More...
 
static void gmx_simdcall gmx::sinCosSingleAccuracy (SimdFloat x, SimdFloat *sinval, SimdFloat *cosval)
 SIMD float sin & cos, only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::sinSingleAccuracy (SimdFloat x)
 SIMD float sin(x), only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::cosSingleAccuracy (SimdFloat x)
 SIMD float cos(x), only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::tanSingleAccuracy (SimdFloat x)
 SIMD float tan(x), only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::asinSingleAccuracy (SimdFloat x)
 SIMD float asin(x), only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::acosSingleAccuracy (SimdFloat x)
 SIMD float acos(x), only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::atanSingleAccuracy (SimdFloat x)
 SIMD float atan(x), only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::atan2SingleAccuracy (SimdFloat y, SimdFloat x)
 SIMD float atan2(y,x), only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::pmeForceCorrectionSingleAccuracy (SimdFloat z2)
 SIMD Analytic PME force correction, only targeting single accuracy. More...
 
static SimdFloat gmx_simdcall gmx::pmePotentialCorrectionSingleAccuracy (SimdFloat z2)
 SIMD Analytic PME potential correction, only targeting single accuracy. More...
 
static Simd4Float gmx_simdcall gmx::invsqrtSingleAccuracy (Simd4Float x)
 Calculate 1/sqrt(x) for SIMD4 float, only targeting single accuracy. More...
 
template<typename T , typename TSimd , int simdWidth>
void gmx::test::anonymous_namespace{bootstrap_loadstore.cpp}::loadStoreTester (TSimd gmx_simdcall loadFn(const T *mem), void gmx_simdcall storeFn(T *mem, TSimd), const int loadOffset, const int storeOffset)
 Generic routine to test load & store of SIMD, and check for side effects. More...
 
template<typename T , typename TSimd >
TSimd gmx_simdcall gmx::test::anonymous_namespace{bootstrap_loadstore.cpp}::loadWrapper (const T *m)
 Wrapper to handle proxy objects returned by some load functions. More...
 
template<typename T , typename TSimd >
TSimd gmx_simdcall gmx::test::anonymous_namespace{bootstrap_loadstore.cpp}::loadUWrapper (const T *m)
 Wrapper to handle proxy objects returned by some loadU functions. More...
 
::std::vector< realgmx::test::simdReal2Vector (SimdReal simd)
 Convert SIMD real to std::vector<real>. More...
 
SimdReal gmx::test::vector2SimdReal (const std::vector< real > &v)
 Return floating-point SIMD value from std::vector<real>. More...
 
SimdReal gmx::test::setSimdRealFrom3R (real r0, real r1, real r2)
 Set SIMD register contents from three real values. More...
 
SimdReal gmx::test::setSimdRealFrom1R (real value)
 Set SIMD register contents from single real value. More...
 
std::vector< std::int32_t > gmx::test::simdInt2Vector (SimdInt32 simd)
 Convert SIMD integer to std::vector<int>. More...
 
SimdInt32 gmx::test::vector2SimdInt (const std::vector< std::int32_t > &v)
 Return 32-bit integer SIMD value from std::vector<int>. More...
 
SimdInt32 gmx::test::setSimdIntFrom3I (int i0, int i1, int i2)
 Set SIMD register contents from three int values. More...
 
SimdInt32 gmx::test::setSimdIntFrom1I (int value)
 Set SIMD register contents from single integer value. More...
 
::std::vector< realgmx::test::simd4Real2Vector (Simd4Real simd4)
 Convert SIMD4 real to std::vector<real>. More...
 
Simd4Real gmx::test::vector2Simd4Real (const std::vector< real > &v)
 Return floating-point SIMD4 value from std::vector<real>. More...
 
Simd4Real gmx::test::setSimd4RealFrom3R (real r0, real r1, real r2)
 Set SIMD4 register contents from three real values. More...
 
Simd4Real gmx::test::setSimd4RealFrom1R (real value)
 Set SIMD4 register contents from single real value. More...
 
real gmx::test::anonymous_namespace{simd_math.cpp}::refInvsqrt (real x)
 Function wrapper to evaluate reference 1/sqrt(x)
 
SimdReal gmx_simdcall gmx::test::anonymous_namespace{simd_math.cpp}::tstInvsqrtPair0 (SimdReal x)
 Function wrapper to return first result when testing invsqrtPair.
 
SimdReal gmx_simdcall gmx::test::anonymous_namespace{simd_math.cpp}::tstInvsqrtPair1 (SimdReal x)
 Function wrapper to return second result when testing invsqrtPair.
 
real gmx::test::anonymous_namespace{simd_math.cpp}::refSqrt (real x)
 Function wrapper to evaluate reference sqrt(x)
 
real gmx::test::anonymous_namespace{simd_math.cpp}::refInv (real x)
 Function wrapper to evaluate reference 1/x.
 
real gmx::test::anonymous_namespace{simd_math.cpp}::refInvCbrt (real x)
 Function wrapper to evaluate reference 1/cbrt(x)
 
real gmx::test::anonymous_namespace{simd_math.cpp}::refErf (real x)
 Function wrapper for erf(x), with argument/return in default Gromacs precision. More...
 
real gmx::test::anonymous_namespace{simd_math.cpp}::refErfc (real x)
 Function wrapper for erfc(x), with argument/return in default Gromacs precision. More...
 
real gmx::test::anonymous_namespace{simd_math.cpp}::refPmeForceCorrection (real x)
 Evaluate reference version of PME force correction.
 
real gmx::test::anonymous_namespace{simd_math.cpp}::refPmePotentialCorrection (real x)
 Evaluate reference version of PME potential correction.
 
SimdReal gmx_simdcall gmx::test::anonymous_namespace{simd_math.cpp}::tst_invsqrt_SingleAccuracy_pair0 (SimdReal x)
 Function wrapper to return first result when testing invsqrtPairSingleAccuracy.
 
SimdReal gmx_simdcall gmx::test::anonymous_namespace{simd_math.cpp}::tst_invsqrt_SingleAccuracy_pair1 (SimdReal x)
 Function wrapper to return second result when testing invsqrtPairSingleAccuracy.
 
static SimdFloat gmx_simdcall gmx::iprod (SimdFloat ax, SimdFloat ay, SimdFloat az, SimdFloat bx, SimdFloat by, SimdFloat bz)
 SIMD float inner product of multiple float vectors. More...
 
static SimdFloat gmx_simdcall gmx::norm2 (SimdFloat ax, SimdFloat ay, SimdFloat az)
 SIMD float norm squared of multiple vectors. More...
 
static void gmx_simdcall gmx::cprod (SimdFloat ax, SimdFloat ay, SimdFloat az, SimdFloat bx, SimdFloat by, SimdFloat bz, SimdFloat *cx, SimdFloat *cy, SimdFloat *cz)
 SIMD float cross-product of multiple vectors. More...
 
static SimdDouble gmx_simdcall gmx::iprod (SimdDouble ax, SimdDouble ay, SimdDouble az, SimdDouble bx, SimdDouble by, SimdDouble bz)
 SIMD double inner product of multiple double vectors. More...
 
static SimdDouble gmx_simdcall gmx::norm2 (SimdDouble ax, SimdDouble ay, SimdDouble az)
 SIMD double norm squared of multiple vectors. More...
 
static void gmx_simdcall gmx::cprod (SimdDouble ax, SimdDouble ay, SimdDouble az, SimdDouble bx, SimdDouble by, SimdDouble bz, SimdDouble *cx, SimdDouble *cy, SimdDouble *cz)
 SIMD double cross-product of multiple vectors. More...
 
static Simd4Float gmx_simdcall gmx::norm2 (Simd4Float ax, Simd4Float ay, Simd4Float az)
 SIMD4 float norm squared of multiple vectors. More...
 
static Simd4Double gmx_simdcall gmx::norm2 (Simd4Double ax, Simd4Double ay, Simd4Double az)
 SIMD4 double norm squared of multiple vectors. More...
 
::testing::AssertionResult gmx::test::SimdBaseTest::compareVectorRealUlp (const char *refExpr, const char *tstExpr, const std::vector< real > &ref, const std::vector< real > &tst)
 Compare two std::vector<real> for approximate equality. More...
 
::testing::AssertionResult gmx::test::SimdTest::compareSimdRealUlp (const char *refExpr, const char *tstExpr, SimdReal ref, SimdReal tst)
 Compare two real SIMD variables for approximate equality. More...
 
::testing::AssertionResult gmx::test::SimdTest::compareSimdEq (const char *refExpr, const char *tstExpr, SimdReal ref, SimdReal tst)
 Compare two real SIMD variables for exact equality. More...
 
::testing::AssertionResult gmx::test::SimdTest::compareSimdEq (const char *refExpr, const char *tstExpr, SimdInt32 ref, SimdInt32 tst)
 Compare two 32-bit integer SIMD variables. More...
 
::testing::AssertionResult gmx::test::Simd4Test::compareSimd4RealUlp (const char *refExpr, const char *tstExpr, Simd4Real ref, Simd4Real tst)
 Compare two real SIMD4 variables for approximate equality. More...
 
::testing::AssertionResult gmx::test::Simd4Test::compareSimd4RealEq (const char *refExpr, const char *tstExpr, Simd4Real ref, Simd4Real tst)
 Compare two real SIMD4 variables for exact equality. More...
 
std::vector< realgmx::test::SimdMathTest::generateTestPoints (Range range, std::size_t points)
 Generate test point vector. More...
 
::testing::AssertionResult gmx::test::SimdMathTest::compareSimdMathFunction (const char *refFuncExpr, const char *simdFuncExpr, const char *compareSettingsExpr, real refFunc(real x), SimdReal gmx_simdcall simdFunc(SimdReal x), const CompareSettings &compareSettings)
 Implementation routine to compare SIMD vs reference functions. More...
 
void gmx::test::SimdMathTest::generateTestPointsTest ()
 Test routine for the test point vector generation.
 

Variables

static const int gmx::c_simdBestPairAlignmentDouble = 2
 Best alignment to use for aligned pairs of double data. More...
 
static const int gmx::c_simdBestPairAlignmentFloat = 2
 Best alignment to use for aligned pairs of float data. More...
 
constexpr real gmx::test::czero = 0.0
 zero
 
constexpr real gmx::test::c0 = 0.3333333333333333
 test constant 0.0 + 1.0/3.0
 
constexpr real gmx::test::c1 = 1.7142857142857144
 test constant 1.0 + 5.0/7.0
 
constexpr real gmx::test::c2 = 2.6923076923076925
 test constant 2.0 + 9.0/13.0
 
constexpr real gmx::test::c3 = 3.8947368421052633
 test constant 3.0 + 17.0/19.0
 
constexpr real gmx::test::c4 = 4.793103448275862
 test constant 4.0 + 23.0/29.0
 
constexpr real gmx::test::c5 = 5.837837837837838
 test constant 5.0 + 31.0/37.0
 
constexpr real gmx::test::c6 = 6.953488372093023
 test constant 6.0 + 41.0/43.0
 
constexpr real gmx::test::c7 = 7.886792452830189
 test constant 7.0 + 47.0/53.0
 
constexpr real gmx::test::c8 = 8.967213114754099
 test constant 8.0 + 59.0/61.0
 
const SimdReal gmx::test::rSimd_c0c1c2 = setSimdRealFrom3R(c0, c1, c2)
 c0,c1,c2 repeated
 
const SimdReal gmx::test::rSimd_c3c4c5 = setSimdRealFrom3R(c3, c4, c5)
 c3,c4,c5 repeated
 
const SimdReal gmx::test::rSimd_c6c7c8 = setSimdRealFrom3R(c6, c7, c8)
 c6,c7,c8 repeated
 
const SimdReal gmx::test::rSimd_c3c0c4 = setSimdRealFrom3R(c3, c0, c4)
 c3,c0,c4 repeated
 
const SimdReal gmx::test::rSimd_c4c6c8 = setSimdRealFrom3R(c4, c6, c8)
 c4,c6,c8 repeated
 
const SimdReal gmx::test::rSimd_c7c2c3 = setSimdRealFrom3R(c7, c2, c3)
 c7,c2,c3 repeated
 
const SimdReal gmx::test::rSimd_m0m1m2 = setSimdRealFrom3R(-c0, -c1, -c2)
 -c0,-c1,-c2 repeated
 
const SimdReal gmx::test::rSimd_m3m0m4 = setSimdRealFrom3R(-c3, -c0, -c4)
 -c3,-c0,-c4 repeated
 
const SimdReal gmx::test::rSimd_2p25 = setSimdRealFrom1R(2.25)
 Value that rounds down.
 
const SimdReal gmx::test::rSimd_3p25 = setSimdRealFrom1R(3.25)
 Value that rounds down.
 
const SimdReal gmx::test::rSimd_3p75 = setSimdRealFrom1R(3.75)
 Value that rounds up.
 
const SimdReal gmx::test::rSimd_m2p25 = setSimdRealFrom1R(-2.25)
 Negative value that rounds up.
 
const SimdReal gmx::test::rSimd_m3p25 = setSimdRealFrom1R(-3.25)
 Negative value that rounds up.
 
const SimdReal gmx::test::rSimd_m3p75 = setSimdRealFrom1R(-3.75)
 Negative value that rounds down. More...
 
const SimdReal gmx::test::rSimd_Exp
 Three large floating-point values whose exponents are >32. More...
 
const SimdReal gmx::test::rSimd_logicalA = setSimdRealFrom1R(1.3333282470703125)
 Bit pattern to test logical ops.
 
const SimdReal gmx::test::rSimd_logicalB = setSimdRealFrom1R(1.79998779296875)
 Bit pattern to test logical ops.
 
const SimdReal gmx::test::rSimd_logicalResultAnd = setSimdRealFrom1R(1.26666259765625)
 Result or bitwise 'and' of A and B.
 
const SimdReal gmx::test::rSimd_logicalResultOr = setSimdRealFrom1R(1.8666534423828125)
 Result or bitwise 'or' of A and B.
 
const SimdInt32 gmx::test::iSimd_1_2_3 = setSimdIntFrom3I(1, 2, 3)
 Three generic ints.
 
const SimdInt32 gmx::test::iSimd_4_5_6 = setSimdIntFrom3I(4, 5, 6)
 Three generic ints.
 
const SimdInt32 gmx::test::iSimd_7_8_9 = setSimdIntFrom3I(7, 8, 9)
 Three generic ints.
 
const SimdInt32 gmx::test::iSimd_5_7_9 = setSimdIntFrom3I(5, 7, 9)
 iSimd_1_2_3 + iSimd_4_5_6.
 
const SimdInt32 gmx::test::iSimd_1M_2M_3M = setSimdIntFrom3I(1000000, 2000000, 3000000)
 Term1 for 32bit add/sub.
 
const SimdInt32 gmx::test::iSimd_4M_5M_6M = setSimdIntFrom3I(4000000, 5000000, 6000000)
 Term2 for 32bit add/sub.
 
const SimdInt32 gmx::test::iSimd_5M_7M_9M = setSimdIntFrom3I(5000000, 7000000, 9000000)
 iSimd_1M_2M_3M + iSimd_4M_5M_6M.
 
const SimdInt32 gmx::test::iSimd_0xF0F0F0F0 = setSimdIntFrom1I(0xF0F0F0F0)
 Bitpattern to test integer logical operations.
 
const SimdInt32 gmx::test::iSimd_0xCCCCCCCC = setSimdIntFrom1I(0xCCCCCCCC)
 Bitpattern to test integer logical operations.
 
const SimdReal gmx::test::rSimd_Bits1
 Pattern F0 repeated to fill single/double.
 
const SimdReal gmx::test::rSimd_Bits2
 Pattern CC repeated to fill single/double.
 
const SimdReal gmx::test::rSimd_Bits3
 Pattern C0 repeated to fill single/double.
 
const SimdReal gmx::test::rSimd_Bits4
 Pattern 0C repeated to fill single/double.
 
const SimdReal gmx::test::rSimd_Bits5
 Pattern FC repeated to fill single/double.
 
const SimdReal gmx::test::rSimd_Bits6
 Pattern 3C repeated to fill single/double.
 
const Simd4Real gmx::test::rSimd4_c0c1c2 = setSimd4RealFrom3R(c0, c1, c2)
 c0,c1,c2 repeated
 
const Simd4Real gmx::test::rSimd4_c3c4c5 = setSimd4RealFrom3R(c3, c4, c5)
 c3,c4,c5 repeated
 
const Simd4Real gmx::test::rSimd4_c6c7c8 = setSimd4RealFrom3R(c6, c7, c8)
 c6,c7,c8 repeated
 
const Simd4Real gmx::test::rSimd4_c3c0c4 = setSimd4RealFrom3R(c3, c0, c4)
 c3,c0,c4 repeated
 
const Simd4Real gmx::test::rSimd4_c4c6c8 = setSimd4RealFrom3R(c4, c6, c8)
 c4,c6,c8 repeated
 
const Simd4Real gmx::test::rSimd4_c7c2c3 = setSimd4RealFrom3R(c7, c2, c3)
 c7,c2,c3 repeated
 
const Simd4Real gmx::test::rSimd4_m0m1m2 = setSimd4RealFrom3R(-c0, -c1, -c2)
 -c0,-c1,-c2 repeated
 
const Simd4Real gmx::test::rSimd4_m3m0m4 = setSimd4RealFrom3R(-c3, -c0, -c4)
 -c3,-c0,-c4 repeated
 
const Simd4Real gmx::test::rSimd4_2p25 = setSimd4RealFrom1R(2.25)
 Value that rounds down.
 
const Simd4Real gmx::test::rSimd4_3p75 = setSimd4RealFrom1R(3.75)
 Value that rounds up.
 
const Simd4Real gmx::test::rSimd4_m2p25 = setSimd4RealFrom1R(-2.25)
 Negative value that rounds up.
 
const Simd4Real gmx::test::rSimd4_m3p75 = setSimd4RealFrom1R(-3.75)
 Negative value that rounds down. More...
 
const Simd4Real gmx::test::rSimd4_logicalA = setSimd4RealFrom1R(1.3333282470703125)
 Bit pattern to test logical ops.
 
const Simd4Real gmx::test::rSimd4_logicalB = setSimd4RealFrom1R(1.79998779296875)
 Bit pattern to test logical ops.
 
const Simd4Real gmx::test::rSimd4_logicalResultAnd = setSimd4RealFrom1R(1.26666259765625)
 Result or bitwise 'and' of A and B.
 
const Simd4Real gmx::test::rSimd4_logicalResultOr = setSimd4RealFrom1R(1.8666534423828125)
 Result or bitwise 'or' of A and B.
 
const Simd4Real gmx::test::rSimd4_Exp
 Three large floating-point values whose exponents are >32.
 
const Simd4Real gmx::test::rSimd4_Bits1
 Pattern F0 repeated to fill single/double.
 
const Simd4Real gmx::test::rSimd4_Bits2
 Pattern CC repeated to fill single/double.
 
const Simd4Real gmx::test::rSimd4_Bits3
 Pattern C0 repeated to fill single/double.
 
const Simd4Real gmx::test::rSimd4_Bits4
 Pattern 0C repeated to fill single/double.
 
const Simd4Real gmx::test::rSimd4_Bits5
 Pattern FC repeated to fill single/double.
 
const Simd4Real gmx::test::rSimd4_Bits6
 Pattern 3C repeated to fill single/double.
 
static int gmx::test::SimdBaseTest::s_nPoints = 10000
 Number of test points to use, settable on command line. More...
 

Directories

directory simd
 SIMD intrinsics interface (simd)
 
directory tests
 Unit tests for SIMD intrinsics interface (simd).
 

Files

file  impl_reference.h
 Reference SIMD implementation, including SIMD documentation.
 
file  impl_reference_definitions.h
 Reference SIMD implementation, including SIMD documentation.
 
file  impl_reference_general.h
 Reference SIMD implementation, general utility functions.
 
file  impl_reference_simd4_double.h
 Reference implementation, SIMD4 single precision.
 
file  impl_reference_simd4_float.h
 Reference implementation, SIMD4 single precision.
 
file  impl_reference_simd_double.h
 Reference implementation, SIMD double precision.
 
file  impl_reference_simd_float.h
 Reference implementation, SIMD single precision.
 
file  impl_reference_util_double.h
 Reference impl., higher-level double prec. SIMD utility functions.
 
file  impl_reference_util_float.h
 Reference impl., higher-level single prec. SIMD utility functions.
 
file  scalar.h
 Scalar float functions corresponding to GROMACS SIMD functions.
 
file  scalar_math.h
 Scalar math functions mimicking GROMACS SIMD math functions.
 
file  scalar_util.h
 Scalar utility functions mimicking GROMACS SIMD utility functions.
 
file  simd.h
 Definitions, capabilities, and wrappers for SIMD module.
 
file  simd_math.h
 Math functions for SIMD datatypes.
 
file  simd_memory.h
 Declares SimdArrayRef.
 
file  support.cpp
 Implements SIMD architecture support query routines.
 
file  support.h
 Functions to query compiled and supported SIMD architectures.
 
file  base.h
 Declares common base class for testing SIMD and SIMD4.
 
file  bootstrap_loadstore.cpp
 Separate test of SIMD load/store, before we use them in the SIMD test classes.
 
file  data.h
 Common test data constants for SIMD, SIMD4 and scalar tests.
 
file  simd.h
 Declares fixture for testing of normal SIMD (not SIMD4) functionality.
 
file  simd4.h
 Declares fixture for testing of SIMD4 functionality.
 
file  simd_memory.cpp
 Tests for gmx::ArrayRef for SIMD types.
 
file  vector_operations.h
 SIMD operations corresponding to Gromacs rvec datatypes.
 

Macro Definition Documentation

#define GMX_EXPECT_SIMD_FUNC_NEAR (   refFunc,
  tstFunc,
  compareSettings 
)    EXPECT_PRED_FORMAT3(compareSimdMathFunction, refFunc, tstFunc, compareSettings)

Test approximate equality of SIMD vs reference version of a function.

This macro takes vanilla C and SIMD flavors of a function and tests it with the number of points, range, and tolerances specified by the test fixture class.

The third option controls the range, tolerances, and match settings.

#define GMX_EXPECT_SIMD_INT_EQ (   ref,
  tst 
)    EXPECT_PRED_FORMAT2(compareSimdEq, ref, tst)

Macro that checks SIMD integer expression against SIMD or reference int.

If the reference argument is a scalar integer it will be expanded into the width of the SIMD register and tested against all elements.

#define GMX_SIMD4_HAVE_REAL   GMX_SIMD4_HAVE_FLOAT

1 if Simd4Real is available, otherwise 0.

GMX_SIMD4_HAVE_DOUBLE if GMX_DOUBLE is 1, otherwise GMX_SIMD4_HAVE_FLOAT.

#define GMX_SIMD_HAVE_GATHER_LOADU_BYSIMDINT_TRANSPOSE_REAL   GMX_SIMD_HAVE_GATHER_LOADU_BYSIMDINT_TRANSPOSE_FLOAT

1 if gmx::simdGatherLoadUBySimdIntTranspose is present, otherwise 0

GMX_SIMD_HAVE_GATHER_LOADU_BYSIMDINT_TRANSPOSE_DOUBLE if GMX_DOUBLE is 1, otherwise GMX_SIMD_HAVE_GATHER_LOADU_BYSIMDINT_TRANSPOSE_FLOAT.

#define GMX_SIMD_HAVE_HSIMD_UTIL_REAL   GMX_SIMD_HAVE_HSIMD_UTIL_FLOAT

1 if real half-register load/store/reduce utils present, otherwise 0

GMX_SIMD_HAVE_HSIMD_UTIL_DOUBLE if GMX_DOUBLE is 1, otherwise GMX_SIMD_HAVE_HSIMD_UTIL_FLOAT.

#define GMX_SIMD_HAVE_INT32_ARITHMETICS   GMX_SIMD_HAVE_FINT32_ARITHMETICS

1 if arithmetic ops are supported on SimdInt32, otherwise 0.

GMX_SIMD_HAVE_DINT32_ARITHMETICS if GMX_DOUBLE is 1, otherwise GMX_SIMD_HAVE_FINT32_ARITHMETICS.

#define GMX_SIMD_HAVE_INT32_EXTRACT   GMX_SIMD_HAVE_FINT32_EXTRACT

1 if support is available for extracting elements from SimdInt32, otherwise 0

GMX_SIMD_HAVE_DINT32_EXTRACT if GMX_DOUBLE is 1, otherwise GMX_SIMD_HAVE_FINT32_EXTRACT.

#define GMX_SIMD_HAVE_INT32_LOGICAL   GMX_SIMD_HAVE_FINT32_LOGICAL

1 if logical ops are supported on SimdInt32, otherwise 0.

GMX_SIMD_HAVE_DINT32_LOGICAL if GMX_DOUBLE is 1, otherwise GMX_SIMD_HAVE_FINT32_LOGICAL.

#define GMX_SIMD_HAVE_REAL   GMX_SIMD_HAVE_FLOAT

1 if SimdReal is available, otherwise 0.

GMX_SIMD_HAVE_DOUBLE if GMX_DOUBLE is 1, otherwise GMX_SIMD_HAVE_FLOAT.

#define GMX_SIMD_REAL_WIDTH   GMX_SIMD_FLOAT_WIDTH

Width of SimdReal.

GMX_SIMD_DOUBLE_WIDTH if GMX_DOUBLE is 1, otherwise GMX_SIMD_FLOAT_WIDTH.

Typedef Documentation

typedef SimdTest gmx::test::anonymous_namespace{simd_vector_operations.cpp}::SimdVectorOperationsTest

Test fixture for vector operations tests (identical to the generic SimdTest)

Function Documentation

static Simd4Float gmx_simdcall gmx::abs ( Simd4Float  a)
inlinestatic

SIMD4 Floating-point fabs().

Parameters
aany floating point values
Returns
fabs(a) for each element.
static Simd4Double gmx_simdcall gmx::abs ( Simd4Double  a)
inlinestatic

SIMD4 Floating-point abs().

Parameters
aany floating point values
Returns
fabs(a) for each element.
static SimdFloat gmx_simdcall gmx::acos ( SimdFloat  x)
inlinestatic

SIMD float acos(x).

Parameters
xThe argument to evaluate acos for
Returns
Acos(x)
static SimdDouble gmx_simdcall gmx::acos ( SimdDouble  x)
inlinestatic

SIMD double acos(x).

Parameters
xThe argument to evaluate acos for
Returns
Acos(x)
static SimdDouble gmx_simdcall gmx::acosSingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD acos(x). Double precision SIMD data, single accuracy.

Parameters
xThe argument to evaluate acos for
Returns
Acos(x)
static SimdFloat gmx_simdcall gmx::acosSingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float acos(x), only targeting single accuracy.

Parameters
xThe argument to evaluate acos for
Returns
Acos(x)
static Simd4Double gmx_simdcall gmx::andNot ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

Bitwise andnot for two SIMD4 double variables. c=(~a) & b.

Available if GMX_SIMD_HAVE_LOGICAL is 1.

Parameters
adata1
bdata2
Returns
(~data1) & data2
static Simd4Float gmx_simdcall gmx::andNot ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

Bitwise andnot for two SIMD4 float variables. c=(~a) & b.

Available if GMX_SIMD_HAVE_LOGICAL is 1.

Parameters
adata1
bdata2
Returns
(~data1) & data2
static bool gmx_simdcall gmx::anyTrue ( Simd4FBool  a)
inlinestatic

Returns non-zero if any of the boolean in SIMD4 a is True, otherwise 0.

Parameters
aLogical variable.
Returns
true if any element in a is true, otherwise false.

The actual return value for truth will depend on the architecture, so any non-zero value is considered truth.

static bool gmx_simdcall gmx::anyTrue ( Simd4DBool  a)
inlinestatic

Returns non-zero if any of the boolean in SIMD4 a is True, otherwise 0.

Parameters
aLogical variable.
Returns
true if any element in a is true, otherwise false.

The actual return value for truth will depend on the architecture, so any non-zero value is considered truth.

static SimdFloat gmx_simdcall gmx::asin ( SimdFloat  x)
inlinestatic

SIMD float asin(x).

Parameters
xThe argument to evaluate asin for
Returns
Asin(x)
static SimdDouble gmx_simdcall gmx::asin ( SimdDouble  x)
inlinestatic

SIMD double asin(x).

Parameters
xThe argument to evaluate asin for
Returns
Asin(x)
static SimdDouble gmx_simdcall gmx::asinSingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD asin(x). Double precision SIMD data, single accuracy.

Parameters
xThe argument to evaluate asin for
Returns
Asin(x)
static SimdFloat gmx_simdcall gmx::asinSingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float asin(x), only targeting single accuracy.

Parameters
xThe argument to evaluate asin for
Returns
Asin(x)
static SimdFloat gmx_simdcall gmx::atan ( SimdFloat  x)
inlinestatic

SIMD float asin(x).

Parameters
xThe argument to evaluate atan for
Returns
Atan(x), same argument/value range as standard math library.
static SimdDouble gmx_simdcall gmx::atan ( SimdDouble  x)
inlinestatic

SIMD double asin(x).

Parameters
xThe argument to evaluate atan for
Returns
Atan(x), same argument/value range as standard math library.
static SimdFloat gmx_simdcall gmx::atan2 ( SimdFloat  y,
SimdFloat  x 
)
inlinestatic

SIMD float atan2(y,x).

Parameters
yY component of vector, any quartile
xX component of vector, any quartile
Returns
Atan(y,x), same argument/value range as standard math library.
Note
This routine should provide correct results for all finite non-zero or positive-zero arguments. However, negative zero arguments will be treated as positive zero, which means the return value will deviate from the standard math library atan2(y,x) for those cases. That should not be of any concern in Gromacs, and in particular it will not affect calculations of angles from vectors.
static SimdDouble gmx_simdcall gmx::atan2 ( SimdDouble  y,
SimdDouble  x 
)
inlinestatic

SIMD double atan2(y,x).

Parameters
yY component of vector, any quartile
xX component of vector, any quartile
Returns
Atan(y,x), same argument/value range as standard math library.
Note
This routine should provide correct results for all finite non-zero or positive-zero arguments. However, negative zero arguments will be treated as positive zero, which means the return value will deviate from the standard math library atan2(y,x) for those cases. That should not be of any concern in Gromacs, and in particular it will not affect calculations of angles from vectors.
static SimdDouble gmx_simdcall gmx::atan2SingleAccuracy ( SimdDouble  y,
SimdDouble  x 
)
inlinestatic

SIMD atan2(y,x). Double precision SIMD data, single accuracy.

Parameters
yY component of vector, any quartile
xX component of vector, any quartile
Returns
Atan(y,x), same argument/value range as standard math library.
Note
This routine should provide correct results for all finite non-zero or positive-zero arguments. However, negative zero arguments will be treated as positive zero, which means the return value will deviate from the standard math library atan2(y,x) for those cases. That should not be of any concern in Gromacs, and in particular it will not affect calculations of angles from vectors.
static SimdFloat gmx_simdcall gmx::atan2SingleAccuracy ( SimdFloat  y,
SimdFloat  x 
)
inlinestatic

SIMD float atan2(y,x), only targeting single accuracy.

Parameters
yY component of vector, any quartile
xX component of vector, any quartile
Returns
Atan(y,x), same argument/value range as standard math library.
Note
This routine should provide correct results for all finite non-zero or positive-zero arguments. However, negative zero arguments will be treated as positive zero, which means the return value will deviate from the standard math library atan2(y,x) for those cases. That should not be of any concern in Gromacs, and in particular it will not affect calculations of angles from vectors.
static SimdDouble gmx_simdcall gmx::atanSingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD asin(x). Double precision SIMD data, single accuracy.

Parameters
xThe argument to evaluate atan for
Returns
Atan(x), same argument/value range as standard math library.
static SimdFloat gmx_simdcall gmx::atanSingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float atan(x), only targeting single accuracy.

Parameters
xThe argument to evaluate atan for
Returns
Atan(x), same argument/value range as standard math library.
static Simd4Float gmx_simdcall gmx::blend ( Simd4Float  a,
Simd4Float  b,
Simd4FBool  sel 
)
inlinestatic

Vector-blend SIMD4 selection.

Parameters
aFirst source
bSecond source
selBoolean selector
Returns
For each element, select b if sel is true, a otherwise.
static Simd4Double gmx_simdcall gmx::blend ( Simd4Double  a,
Simd4Double  b,
Simd4DBool  sel 
)
inlinestatic

Vector-blend SIMD4 selection.

Parameters
aFirst source
bSecond source
selBoolean selector
Returns
For each element, select b if sel is true, a otherwise.
static SimdFloat gmx_simdcall gmx::cbrt ( SimdFloat  x)
inlinestatic

Cube root for SIMD floats.

Parameters
xArgument to calculate cube root of. Can be negative or zero, but NaN or Inf values are not supported. Denormal values will be treated as 0.0.
Returns
Cube root of x.
static SimdDouble gmx_simdcall gmx::cbrt ( SimdDouble  x)
inlinestatic

Cube root for SIMD doubles.

Parameters
xArgument to calculate cube root of. Can be negative or zero, but NaN or Inf values are not supported. Denormal values will be treated as 0.0.
Returns
Cube root of x.
static SimdDouble gmx_simdcall gmx::cbrtSingleAccuracy ( SimdDouble  x)
inlinestatic

Cube root for SIMD doubles, single accuracy.

Parameters
xArgument to calculate cube root of. Can be negative or zero, but NaN or Inf values are not supported. Denormal values will be treated as 0.0.
Returns
Cube root of x.
static SimdFloat gmx_simdcall gmx::cbrtSingleAccuracy ( SimdFloat  x)
inlinestatic

Calculate cbrt(x) for SIMD float, always targeting single accuracy.

Parameters
xArgument to calculate cube root of. Can be negative or zero, but NaN or Inf values are not supported. Denormal values will be treated as 0.0.
Returns
Cube root of x.
testing::AssertionResult gmx::test::Simd4Test::compareSimd4RealEq ( const char *  refExpr,
const char *  tstExpr,
Simd4Real  ref,
Simd4Real  tst 
)

Compare two real SIMD4 variables for exact equality.

This is an internal implementation routine. YOu should always use GMX_EXPECT_SIMD4_REAL_NEAR() instead.

This routine is designed according to the Google test specs, so the char strings will describe the arguments to the macro.

The comparison is applied to each element, and it returns true if each element in the SIMD4 test variable is within the class tolerances of the corresponding reference element.

testing::AssertionResult gmx::test::Simd4Test::compareSimd4RealUlp ( const char *  refExpr,
const char *  tstExpr,
Simd4Real  ref,
Simd4Real  tst 
)

Compare two real SIMD4 variables for approximate equality.

This is an internal implementation routine. YOu should always use GMX_EXPECT_SIMD4_REAL_NEAR() instead.

This routine is designed according to the Google test specs, so the char strings will describe the arguments to the macro.

The comparison is applied to each element, and it returns true if each element in the SIMD4 test variable is within the class tolerances of the corresponding reference element.

testing::AssertionResult gmx::test::SimdTest::compareSimdEq ( const char *  refExpr,
const char *  tstExpr,
SimdReal  ref,
SimdReal  tst 
)

Compare two real SIMD variables for exact equality.

This is an internal implementation routine. YOu should always use GMX_EXPECT_SIMD_REAL_NEAR() instead.

This routine is designed according to the Google test specs, so the char strings will describe the arguments to the macro.

The comparison is applied to each element, and it returns true if each element in the SIMD test variable is within the class tolerances of the corresponding reference element.

testing::AssertionResult gmx::test::SimdTest::compareSimdEq ( const char *  refExpr,
const char *  tstExpr,
SimdInt32  ref,
SimdInt32  tst 
)

Compare two 32-bit integer SIMD variables.

This is an internal implementation routine. YOu should always use GMX_EXPECT_SIMD_INT_EQ() instead.

This routine is designed according to the Google test specs, so the char strings will describe the arguments to the macro, while the SIMD and tolerance arguments are used to decide if the values are approximately equal.

The comparison is applied to each element, and it returns true if each element in the SIMD variable tst is identical to the corresponding reference element.

testing::AssertionResult gmx::test::SimdMathTest::compareSimdMathFunction ( const char *  refFuncExpr,
const char *  simdFuncExpr,
const char *  compareSettingsExpr,
real   refFuncreal x,
SimdReal gmx_simdcall   simdFuncSimdReal x,
const CompareSettings compareSettings 
)

Implementation routine to compare SIMD vs reference functions.

Parameters
refFuncExprDescription of reference function expression
simdFuncExprDescription of SIMD function expression
compareSettingsExprDescription of compareSettings
refFuncReference math function pointer
simdFuncSIMD math function pointer
compareSettingsStructure with the range, tolerances, and matching rules to use for the comparison.
Note
You should not never call this function directly, but use the macro GMX_EXPECT_SIMD_FUNC_NEAR(refFunc,tstFunc,matchRule) instead.
testing::AssertionResult gmx::test::SimdTest::compareSimdRealUlp ( const char *  refExpr,
const char *  tstExpr,
SimdReal  ref,
SimdReal  tst 
)

Compare two real SIMD variables for approximate equality.

This is an internal implementation routine. YOu should always use GMX_EXPECT_SIMD_REAL_NEAR() instead.

This routine is designed according to the Google test specs, so the char strings will describe the arguments to the macro.

The comparison is applied to each element, and it returns true if each element in the SIMD test variable is within the class tolerances of the corresponding reference element.

testing::AssertionResult gmx::test::SimdBaseTest::compareVectorRealUlp ( const char *  refExpr,
const char *  tstExpr,
const std::vector< real > &  ref,
const std::vector< real > &  tst 
)

Compare two std::vector<real> for approximate equality.

This is an internal implementation routine that will be used by routines in derived child classes that first convert SIMD or SIMD4 variables to std::vector<real>. Do not call it directly.

This routine is designed according to the Google test specs, so the char strings will describe the arguments to the macro.

The comparison is applied to each element, and it returns true if each element in the vector test variable is within the class tolerances of the corresponding reference elements.

static SimdFloat gmx_simdcall gmx::copysign ( SimdFloat  x,
SimdFloat  y 
)
inlinestatic

Composes floating point value with the magnitude of x and the sign of y.

Parameters
xValues to set sign for
yValues used to set sign
Returns
Magnitude of x, sign of y
static SimdDouble gmx_simdcall gmx::copysign ( SimdDouble  x,
SimdDouble  y 
)
inlinestatic

Composes floating point value with the magnitude of x and the sign of y.

Parameters
xValues to set sign for
yValues used to set sign
Returns
Magnitude of x, sign of y
static SimdFloat gmx_simdcall gmx::cos ( SimdFloat  x)
inlinestatic

SIMD float cos(x).

Parameters
xThe argument to evaluate cos for
Returns
Cos(x)
Attention
Do NOT call both sin & cos if you need both results, since each of them will then call sincos and waste a factor 2 in performance.
static SimdDouble gmx_simdcall gmx::cos ( SimdDouble  x)
inlinestatic

SIMD double cos(x).

Parameters
xThe argument to evaluate cos for
Returns
Cos(x)
Attention
Do NOT call both sin & cos if you need both results, since each of them will then call sincos and waste a factor 2 in performance.
static SimdDouble gmx_simdcall gmx::cosSingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD cos(x). Double precision SIMD data, single accuracy.

Parameters
xThe argument to evaluate cos for
Returns
Cos(x)
Attention
Do NOT call both sin & cos if you need both results, since each of them will then call sincos and waste a factor 2 in performance.
static SimdFloat gmx_simdcall gmx::cosSingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float cos(x), only targeting single accuracy.

Parameters
xThe argument to evaluate cos for
Returns
Cos(x)
Attention
Do NOT call both sin & cos if you need both results, since each of them will then call sincos and waste a factor 2 in performance.
static void gmx_simdcall gmx::cprod ( SimdFloat  ax,
SimdFloat  ay,
SimdFloat  az,
SimdFloat  bx,
SimdFloat  by,
SimdFloat  bz,
SimdFloat *  cx,
SimdFloat *  cy,
SimdFloat *  cz 
)
inlinestatic

SIMD float cross-product of multiple vectors.

Parameters
axX components of first vectors
ayY components of first vectors
azZ components of first vectors
bxX components of second vectors
byY components of second vectors
bzZ components of second vectors
[out]cxX components of cross product vectors
[out]cyY components of cross product vectors
[out]czZ components of cross product vectors
Returns
void

This calculates C = A x B, where the cross denotes the cross product. The arguments x/y/z denotes the different components, and each element corresponds to a separate vector.

static void gmx_simdcall gmx::cprod ( SimdDouble  ax,
SimdDouble  ay,
SimdDouble  az,
SimdDouble  bx,
SimdDouble  by,
SimdDouble  bz,
SimdDouble *  cx,
SimdDouble *  cy,
SimdDouble *  cz 
)
inlinestatic

SIMD double cross-product of multiple vectors.

Parameters
axX components of first vectors
ayY components of first vectors
azZ components of first vectors
bxX components of second vectors
byY components of second vectors
bzZ components of second vectors
[out]cxX components of cross product vectors
[out]cyY components of cross product vectors
[out]czZ components of cross product vectors
Returns
void

This calculates C = A x B, where the cross denotes the cross product. The arguments x/y/z denotes the different components, and each element corresponds to a separate vector.

static float gmx_simdcall gmx::dotProduct ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

Return dot product of two single precision SIMD4 variables.

The dot product is calculated between the first three elements in the two vectors, while the fourth is ignored. The result is returned as a scalar.

Parameters
avector1
bvector2
Returns
a[0]*b[0]+a[1]*b[1]+a[2]*b[2], returned as scalar. Last element is ignored.
static double gmx_simdcall gmx::dotProduct ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

Return dot product of two double precision SIMD4 variables.

The dot product is calculated between the first three elements in the two vectors, while the fourth is ignored. The result is returned as a scalar.

Parameters
avector1
bvector2
Returns
a[0]*b[0]+a[1]*b[1]+a[2]*b[2], returned as scalar. Last element is ignored.
static SimdFloat gmx_simdcall gmx::erf ( SimdFloat  x)
inlinestatic

SIMD float erf(x).

Parameters
xThe value to calculate erf(x) for.
Returns
erf(x)

This routine achieves very close to full precision, but we do not care about the last bit or the subnormal result range.

static SimdDouble gmx_simdcall gmx::erf ( SimdDouble  x)
inlinestatic

SIMD double erf(x).

Parameters
xThe value to calculate erf(x) for.
Returns
erf(x)

This routine achieves very close to full precision, but we do not care about the last bit or the subnormal result range.

static SimdFloat gmx_simdcall gmx::erfc ( SimdFloat  x)
inlinestatic

SIMD float erfc(x).

Parameters
xThe value to calculate erfc(x) for.
Returns
erfc(x)

This routine achieves full precision (bar the last bit) over most of the input range, but for large arguments where the result is getting close to the minimum representable numbers we accept slightly larger errors (think results that are in the ballpark of 10^-30 for single precision) since that is not relevant for MD.

static SimdDouble gmx_simdcall gmx::erfc ( SimdDouble  x)
inlinestatic

SIMD double erfc(x).

Parameters
xThe value to calculate erfc(x) for.
Returns
erfc(x)

This routine achieves full precision (bar the last bit) over most of the input range, but for large arguments where the result is getting close to the minimum representable numbers we accept slightly larger errors (think results that are in the ballpark of 10^-200 for double) since that is not relevant for MD.

static SimdDouble gmx_simdcall gmx::erfcSingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD erfc(x). Double precision SIMD data, single accuracy.

Parameters
xThe value to calculate erfc(x) for.
Returns
erfc(x)

This routine achieves singleprecision (bar the last bit) over most of the input range, but for large arguments where the result is getting close to the minimum representable numbers we accept slightly larger errors (think results that are in the ballpark of 10^-30) since that is not relevant for MD.

static SimdFloat gmx_simdcall gmx::erfcSingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float erfc(x), only targeting single accuracy.

Parameters
xThe value to calculate erfc(x) for.
Returns
erfc(x)

This routine achieves singleprecision (bar the last bit) over most of the input range, but for large arguments where the result is getting close to the minimum representable numbers we accept slightly larger errors (think results that are in the ballpark of 10^-30) since that is not relevant for MD.

static SimdDouble gmx_simdcall gmx::erfSingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD erf(x). Double precision SIMD data, single accuracy.

Parameters
xThe value to calculate erf(x) for.
Returns
erf(x)

This routine achieves very close to single precision, but we do not care about the last bit or the subnormal result range.

static SimdFloat gmx_simdcall gmx::erfSingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float erf(x), only targeting single accuracy.

Parameters
xThe value to calculate erf(x) for.
Returns
erf(x)

This routine achieves very close to single precision, but we do not care about the last bit or the subnormal result range.

template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::exp ( SimdFloat  x)
inlinestatic

SIMD float exp(x).

In addition to scaling the argument for 2^x this routine correctly does extended precision arithmetics to improve accuracy.

Template Parameters
optIf this is changed from the default (safe) into the unsafe option, input values that would otherwise lead to zero-clamped results are not allowed and will lead to undefined results.
Parameters
xArgument. For the default (safe) function version this can be arbitrarily small value, but the routine might clamp the result to zero for arguments that would produce subnormal IEEE754-2008 results. This corresponds to input arguments reaching -126*ln(2)=-87.3 in single, or -1022*ln(2)=-708.4 (double). Similarly, it might overflow for arguments reaching 127*ln(2)=88.0 (single) or 1023*ln(2)=709.1 (double). If the unsafe math optimizations are enabled, small input values that would result in zero-clamped output are not allowed.
Returns
exp(x). Overflowing arguments are likely to either return 0 or inf, depending on the underlying implementation. If unsafe optimizations are enabled, this is also true for very small values.
Note
The definition range of this function is just-so-slightly smaller than the allowed IEEE exponents for many architectures. This is due to the implementation, which will hopefully improve in the future.
Warning
You cannot rely on this implementation returning inf for arguments that cause overflow. If you have some very large values and need to rely on getting a valid numerical output, take the minimum of your variable and the largest valid argument before calling this routine.
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::exp ( SimdDouble  x)
inlinestatic

SIMD double exp(x).

In addition to scaling the argument for 2^x this routine correctly does extended precision arithmetics to improve accuracy.

Template Parameters
optIf this is changed from the default (safe) into the unsafe option, input values that would otherwise lead to zero-clamped results are not allowed and will lead to undefined results.
Parameters
xArgument. For the default (safe) function version this can be arbitrarily small value, but the routine might clamp the result to zero for arguments that would produce subnormal IEEE754-2008 results. This corresponds to input arguments reaching -126*ln(2)=-87.3 in single, or -1022*ln(2)=-708.4 (double). Similarly, it might overflow for arguments reaching 127*ln(2)=88.0 (single) or 1023*ln(2)=709.1 (double). If the unsafe math optimizations are enabled, small input values that would result in zero-clamped output are not allowed.
Returns
exp(x). Overflowing arguments are likely to either return 0 or inf, depending on the underlying implementation. If unsafe optimizations are enabled, this is also true for very small values.
Note
The definition range of this function is just-so-slightly smaller than the allowed IEEE exponents for many architectures. This is due to the implementation, which will hopefully improve in the future.
Warning
You cannot rely on this implementation returning inf for arguments that cause overflow. If you have some very large values and need to rely on getting a valid numerical output, take the minimum of your variable and the largest valid argument before calling this routine.
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::exp2 ( SimdFloat  x)
inlinestatic

SIMD float 2^x.

Template Parameters
optIf this is changed from the default (safe) into the unsafe option, input values that would otherwise lead to zero-clamped results are not allowed and will lead to undefined results.
Parameters
xArgument. For the default (safe) function version this can be arbitrarily small value, but the routine might clamp the result to zero for arguments that would produce subnormal IEEE754-2008 results. This corresponds to inputs below -126 in single or -1022 in double, and it might overflow for arguments reaching 127 (single) or 1023 (double). If you enable the unsafe math optimization, very small arguments will not necessarily be zero-clamped, but can produce undefined results.
Returns
2^x. The result is undefined for very large arguments that cause internal floating-point overflow. If unsafe optimizations are enabled, this is also true for very small values.
Note
The definition range of this function is just-so-slightly smaller than the allowed IEEE exponents for many architectures. This is due to the implementation, which will hopefully improve in the future.
Warning
You cannot rely on this implementation returning inf for arguments that cause overflow. If you have some very large values and need to rely on getting a valid numerical output, take the minimum of your variable and the largest valid argument before calling this routine.
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::exp2 ( SimdDouble  x)
inlinestatic

SIMD double 2^x.

Template Parameters
optIf this is changed from the default (safe) into the unsafe option, input values that would otherwise lead to zero-clamped results are not allowed and will lead to undefined results.
Parameters
xArgument. For the default (safe) function version this can be arbitrarily small value, but the routine might clamp the result to zero for arguments that would produce subnormal IEEE754-2008 results. This corresponds to inputs below -126 in single or -1022 in double, and it might overflow for arguments reaching 127 (single) or 1023 (double). If you enable the unsafe math optimization, very small arguments will not necessarily be zero-clamped, but can produce undefined results.
Returns
2^x. The result is undefined for very large arguments that cause internal floating-point overflow. If unsafe optimizations are enabled, this is also true for very small values.
Note
The definition range of this function is just-so-slightly smaller than the allowed IEEE exponents for many architectures. This is due to the implementation, which will hopefully improve in the future.
Warning
You cannot rely on this implementation returning inf for arguments that cause overflow. If you have some very large values and need to rely on getting a valid numerical output, take the minimum of your variable and the largest valid argument before calling this routine.
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::exp2SingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD 2^x. Double precision SIMD, single accuracy.

Template Parameters
optIf this is changed from the default (safe) into the unsafe option, input values that would otherwise lead to zero-clamped results are not allowed and will lead to undefined results.
Parameters
xArgument. For the default (safe) function version this can be arbitrarily small value, but the routine might clamp the result to zero for arguments that would produce subnormal IEEE754-2008 results. This corresponds to inputs below -126 in single or -1022 in double, and it might overflow for arguments reaching 127 (single) or 1023 (double). If you enable the unsafe math optimization, very small arguments will not necessarily be zero-clamped, but can produce undefined results.
Returns
2^x. The result is undefined for very large arguments that cause internal floating-point overflow. If unsafe optimizations are enabled, this is also true for very small values.
Note
The definition range of this function is just-so-slightly smaller than the allowed IEEE exponents for many architectures. This is due to the implementation, which will hopefully improve in the future.
Warning
You cannot rely on this implementation returning inf for arguments that cause overflow. If you have some very large values and need to rely on getting a valid numerical output, take the minimum of your variable and the largest valid argument before calling this routine.
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::exp2SingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float 2^x, only targeting single accuracy.

Template Parameters
optIf this is changed from the default (safe) into the unsafe option, input values that would otherwise lead to zero-clamped results are not allowed and will lead to undefined results.
Parameters
xArgument. For the default (safe) function version this can be arbitrarily small value, but the routine might clamp the result to zero for arguments that would produce subnormal IEEE754-2008 results. This corresponds to inputs below -126 in single or -1022 in double, and it might overflow for arguments reaching 127 (single) or 1023 (double). If you enable the unsafe math optimization, very small arguments will not necessarily be zero-clamped, but can produce undefined results.
Returns
2^x. The result is undefined for very large arguments that cause internal floating-point overflow. If unsafe optimizations are enabled, this is also true for very small values.
Note
The definition range of this function is just-so-slightly smaller than the allowed IEEE exponents for many architectures. This is due to the implementation, which will hopefully improve in the future.
Warning
You cannot rely on this implementation returning inf for arguments that cause overflow. If you have some very large values and need to rely on getting a valid numerical output, take the minimum of your variable and the largest valid argument before calling this routine.
static void gmx_simdcall gmx::expandScalarsToTriplets ( SimdDouble  scalar,
SimdDouble *  triplets0,
SimdDouble *  triplets1,
SimdDouble *  triplets2 
)
inlinestatic

Expand each element of double SIMD variable into three identical consecutive elements in three SIMD outputs.

Parameters
scalarFloating-point input, e.g. [s0 s1 s2 s3] if width=4.
[out]triplets0First output, e.g. [s0 s0 s0 s1] if width=4.
[out]triplets1Second output, e.g. [s1 s1 s2 s2] if width=4.
[out]triplets2Third output, e.g. [s2 s3 s3 s3] if width=4.

This routine is meant to use for things like scalar-vector multiplication, where the vectors are stored in a merged format like [x0 y0 z0 x1 y1 z1 ...], while the scalars are stored as [s0 s1 s2...], and the data cannot easily be changed to SIMD-friendly layout.

In this case, load 3 full-width SIMD variables from the vector array (This will always correspond to GMX_SIMD_DOUBLE_WIDTH triplets), load a single full-width variable from the scalar array, and call this routine to expand the data. You can then simply multiply the first, second and third pair of SIMD variables, and store the three results back into a suitable vector-format array.

static void gmx_simdcall gmx::expandScalarsToTriplets ( SimdFloat  scalar,
SimdFloat *  triplets0,
SimdFloat *  triplets1,
SimdFloat *  triplets2 
)
inlinestatic

Expand each element of float SIMD variable into three identical consecutive elements in three SIMD outputs.

Parameters
scalarFloating-point input, e.g. [s0 s1 s2 s3] if width=4.
[out]triplets0First output, e.g. [s0 s0 s0 s1] if width=4.
[out]triplets1Second output, e.g. [s1 s1 s2 s2] if width=4.
[out]triplets2Third output, e.g. [s2 s3 s3 s3] if width=4.

This routine is meant to use for things like scalar-vector multiplication, where the vectors are stored in a merged format like [x0 y0 z0 x1 y1 z1 ...], while the scalars are stored as [s0 s1 s2...], and the data cannot easily be changed to SIMD-friendly layout.

In this case, load 3 full-width SIMD variables from the vector array (This will always correspond to GMX_SIMD_FLOAT_WIDTH triplets), load a single full-width variable from the scalar array, and call this routine to expand the data. You can then simply multiply the first, second and third pair of SIMD variables, and store the three results back into a suitable vector-format array.

template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::expSingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD exp(x). Double precision SIMD, single accuracy.

In addition to scaling the argument for 2^x this routine correctly does extended precision arithmetics to improve accuracy.

Template Parameters
optIf this is changed from the default (safe) into the unsafe option, input values that would otherwise lead to zero-clamped results are not allowed and will lead to undefined results.
Parameters
xArgument. For the default (safe) function version this can be arbitrarily small value, but the routine might clamp the result to zero for arguments that would produce subnormal IEEE754-2008 results. This corresponds to input arguments reaching -126*ln(2)=-87.3 in single, or -1022*ln(2)=-708.4 (double). Similarly, it might overflow for arguments reaching 127*ln(2)=88.0 (single) or 1023*ln(2)=709.1 (double). If the unsafe math optimizations are enabled, small input values that would result in zero-clamped output are not allowed.
Returns
exp(x). Overflowing arguments are likely to either return 0 or inf, depending on the underlying implementation. If unsafe optimizations are enabled, this is also true for very small values.
Note
The definition range of this function is just-so-slightly smaller than the allowed IEEE exponents for many architectures. This is due to the implementation, which will hopefully improve in the future.
Warning
You cannot rely on this implementation returning inf for arguments that cause overflow. If you have some very large values and need to rely on getting a valid numerical output, take the minimum of your variable and the largest valid argument before calling this routine.
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::expSingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float e^x, only targeting single accuracy.

In addition to scaling the argument for 2^x this routine correctly does extended precision arithmetics to improve accuracy.

Template Parameters
optIf this is changed from the default (safe) into the unsafe option, input values that would otherwise lead to zero-clamped results are not allowed and will lead to undefined results.
Parameters
xArgument. For the default (safe) function version this can be arbitrarily small value, but the routine might clamp the result to zero for arguments that would produce subnormal IEEE754-2008 results. This corresponds to input arguments reaching -126*ln(2)=-87.3 in single, or -1022*ln(2)=-708.4 (double). Similarly, it might overflow for arguments reaching 127*ln(2)=88.0 (single) or 1023*ln(2)=709.1 (double). If the unsafe math optimizations are enabled, small input values that would result in zero-clamped output are not allowed.
Returns
exp(x). Overflowing arguments are likely to either return 0 or inf, depending on the underlying implementation. If unsafe optimizations are enabled, this is also true for very small values.
Note
The definition range of this function is just-so-slightly smaller than the allowed IEEE exponents for many architectures. This is due to the implementation, which will hopefully improve in the future.
Warning
You cannot rely on this implementation returning inf for arguments that cause overflow. If you have some very large values and need to rely on getting a valid numerical output, take the minimum of your variable and the largest valid argument before calling this routine.
static Simd4Float gmx_simdcall gmx::fma ( Simd4Float  a,
Simd4Float  b,
Simd4Float  c 
)
inlinestatic

SIMD4 Fused-multiply-add. Result is a*b+c.

Parameters
afactor1
bfactor2
cterm
Returns
a*b+c
static Simd4Double gmx_simdcall gmx::fma ( Simd4Double  a,
Simd4Double  b,
Simd4Double  c 
)
inlinestatic

SIMD4 Fused-multiply-add. Result is a*b+c.

Parameters
afactor1
bfactor2
cterm
Returns
a*b+c
static Simd4Float gmx_simdcall gmx::fms ( Simd4Float  a,
Simd4Float  b,
Simd4Float  c 
)
inlinestatic

SIMD4 Fused-multiply-subtract. Result is a*b-c.

Parameters
afactor1
bfactor2
cterm
Returns
a*b-c
static Simd4Double gmx_simdcall gmx::fms ( Simd4Double  a,
Simd4Double  b,
Simd4Double  c 
)
inlinestatic

SIMD4 Fused-multiply-subtract. Result is a*b-c.

Parameters
afactor1
bfactor2
cterm
Returns
a*b-c
static Simd4Double gmx_simdcall gmx::fnma ( Simd4Double  a,
Simd4Double  b,
Simd4Double  c 
)
inlinestatic

SIMD4 Fused-negated-multiply-add. Result is -a*b+c.

Parameters
afactor1
bfactor2
cterm
Returns
-a*b+c
static Simd4Float gmx_simdcall gmx::fnma ( Simd4Float  a,
Simd4Float  b,
Simd4Float  c 
)
inlinestatic

SIMD4 Fused-negated-multiply-add. Result is -a*b+c.

Parameters
afactor1
bfactor2
cterm
Returns
-a*b+c
static Simd4Double gmx_simdcall gmx::fnms ( Simd4Double  a,
Simd4Double  b,
Simd4Double  c 
)
inlinestatic

SIMD4 Fused-negated-multiply-subtract. Result is -a*b-c.

Parameters
afactor1
bfactor2
cterm
Returns
-a*b-c
static Simd4Float gmx_simdcall gmx::fnms ( Simd4Float  a,
Simd4Float  b,
Simd4Float  c 
)
inlinestatic

SIMD4 Fused-negated-multiply-subtract. Result is -a*b-c.

Parameters
afactor1
bfactor2
cterm
Returns
-a*b-c
template<int align>
static void gmx_simdcall gmx::gatherLoadBySimdIntTranspose ( const double *  base,
SimdDInt32  offset,
SimdDouble *  v0,
SimdDouble *  v1,
SimdDouble *  v2,
SimdDouble *  v3 
)
inlinestatic

Load 4 consecutive doubles from each of GMX_SIMD_DOUBLE_WIDTH offsets specified by a SIMD integer, transpose into 4 SIMD double variables.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 4 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
baseAligned pointer to the start of the memory.
offsetSIMD integer type with offsets to the start of each triplet.
[out]v0First component, base[align*offset[i]] for each i.
[out]v1Second component, base[align*offset[i] + 1] for each i.
[out]v2Third component, base[align*offset[i] + 2] for each i.
[out]v3Fourth component, base[align*offset[i] + 3] for each i.

The floating-point memory locations must be aligned, but only to the smaller of four elements and the floating-point SIMD width.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This is a special routine primarily intended for loading Gromacs table data as efficiently as possible - this is the reason for using a SIMD offset index, since the result of the real-to-integer conversion is present in a SIMD register just before calling this routine.
template<int align>
static void gmx_simdcall gmx::gatherLoadBySimdIntTranspose ( const float *  base,
SimdFInt32  offset,
SimdFloat *  v0,
SimdFloat *  v1,
SimdFloat *  v2,
SimdFloat *  v3 
)
inlinestatic

Load 4 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets specified by a SIMD integer, transpose into 4 SIMD float variables.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 4 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
baseAligned pointer to the start of the memory.
offsetSIMD integer type with offsets to the start of each triplet.
[out]v0First component, base[align*offset[i]] for each i.
[out]v1Second component, base[align*offset[i] + 1] for each i.
[out]v2Third component, base[align*offset[i] + 2] for each i.
[out]v3Fourth component, base[align*offset[i] + 3] for each i.

The floating-point memory locations must be aligned, but only to the smaller of four elements and the floating-point SIMD width.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This is a special routine primarily intended for loading Gromacs table data as efficiently as possible - this is the reason for using a SIMD offset index, since the result of the real-to-integer conversion is present in a SIMD register just before calling this routine.
template<int align>
static void gmx_simdcall gmx::gatherLoadBySimdIntTranspose ( const double *  base,
SimdDInt32  offset,
SimdDouble *  v0,
SimdDouble *  v1 
)
inlinestatic

Load 2 consecutive doubles from each of GMX_SIMD_DOUBLE_WIDTH offsets specified by a SIMD integer, transpose into 2 SIMD double variables.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 2 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
baseAligned pointer to the start of the memory.
offsetSIMD integer type with offsets to the start of each triplet.
[out]v0First component, base[align*offset[i]] for each i.
[out]v1Second component, base[align*offset[i] + 1] for each i.

The floating-point memory locations must be aligned, but only to the smaller of two elements and the floating-point SIMD width.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This is a special routine primarily intended for loading Gromacs table data as efficiently as possible - this is the reason for using a SIMD offset index, since the result of the real-to-integer conversion is present in a SIMD register just before calling this routine.
template<int align>
static void gmx_simdcall gmx::gatherLoadBySimdIntTranspose ( const float *  base,
SimdFInt32  offset,
SimdFloat *  v0,
SimdFloat *  v1 
)
inlinestatic

Load 2 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets specified by a SIMD integer, transpose into 2 SIMD float variables.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 2 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
baseAligned pointer to the start of the memory.
offsetSIMD integer type with offsets to the start of each triplet.
[out]v0First component, base[align*offset[i]] for each i.
[out]v1Second component, base[align*offset[i] + 1] for each i.

The floating-point memory locations must be aligned, but only to the smaller of two elements and the floating-point SIMD width.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This is a special routine primarily intended for loading Gromacs table data as efficiently as possible - this is the reason for using a SIMD offset index, since the result of the real-to-integer conversion is present in a SIMD register just before calling this routine.
template<int align>
static void gmx_simdcall gmx::gatherLoadTranspose ( const double *  base,
const std::int32_t  offset[],
SimdDouble *  v0,
SimdDouble *  v1,
SimdDouble *  v2,
SimdDouble *  v3 
)
inlinestatic

Load 4 consecutive double from each of GMX_SIMD_DOUBLE_WIDTH offsets, and transpose into 4 SIMD double variables.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 4 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
basePointer to the start of the memory area
offsetArray with offsets to the start of each data point.
[out]v01st component of data, base[align*offset[i]] for each i.
[out]v12nd component of data, base[align*offset[i] + 1] for each i.
[out]v23rd component of data, base[align*offset[i] + 2] for each i.
[out]v34th component of data, base[align*offset[i] + 3] for each i.

The floating-point memory locations must be aligned, but only to the smaller of four elements and the floating-point SIMD width.

The offset memory must be aligned to GMX_SIMD_DINT32_WIDTH.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
template<int align>
static void gmx_simdcall gmx::gatherLoadTranspose ( const float *  base,
const std::int32_t  offset[],
SimdFloat *  v0,
SimdFloat *  v1,
SimdFloat *  v2,
SimdFloat *  v3 
)
inlinestatic

Load 4 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets, and transpose into 4 SIMD float variables.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 4 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
basePointer to the start of the memory area
offsetArray with offsets to the start of each data point.
[out]v01st component of data, base[align*offset[i]] for each i.
[out]v12nd component of data, base[align*offset[i] + 1] for each i.
[out]v23rd component of data, base[align*offset[i] + 2] for each i.
[out]v34th component of data, base[align*offset[i] + 3] for each i.

The floating-point memory locations must be aligned, but only to the smaller of four elements and the floating-point SIMD width.

The offset memory must be aligned to GMX_SIMD_DINT32_WIDTH.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
template<int align>
static void gmx_simdcall gmx::gatherLoadTranspose ( const double *  base,
const std::int32_t  offset[],
SimdDouble *  v0,
SimdDouble *  v1 
)
inlinestatic

Load 2 consecutive double from each of GMX_SIMD_DOUBLE_WIDTH offsets, and transpose into 2 SIMD double variables.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 2 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
basePointer to the start of the memory area
offsetArray with offsets to the start of each data point.
[out]v01st component of data, base[align*offset[i]] for each i.
[out]v12nd component of data, base[align*offset[i] + 1] for each i.

The floating-point memory locations must be aligned, but only to the smaller of two elements and the floating-point SIMD width.

The offset memory must be aligned to GMX_SIMD_DINT32_WIDTH.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
template<int align>
static void gmx_simdcall gmx::gatherLoadTranspose ( const float *  base,
const std::int32_t  offset[],
SimdFloat *  v0,
SimdFloat *  v1 
)
inlinestatic

Load 2 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets, and transpose into 2 SIMD float variables.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 2 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
basePointer to the start of the memory area
offsetArray with offsets to the start of each data point.
[out]v01st component of data, base[align*offset[i]] for each i.
[out]v12nd component of data, base[align*offset[i] + 1] for each i.

The floating-point memory locations must be aligned, but only to the smaller of two elements and the floating-point SIMD width.

The offset memory must be aligned to GMX_SIMD_FINT32_WIDTH.

To achieve the best possible performance, you should store your data with alignment c_simdBestPairAlignmentFloat in single, or c_simdBestPairAlignmentDouble in double.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
template<int align>
static void gmx_simdcall gmx::gatherLoadUBySimdIntTranspose ( const double *  base,
SimdDInt32  offset,
SimdDouble *  v0,
SimdDouble *  v1 
)
inlinestatic

Load 2 consecutive doubles from each of GMX_SIMD_DOUBLE_WIDTH offsets (unaligned) specified by SIMD integer, transpose into 2 SIMD doubles.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 2 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
basePointer to the start of the memory.
offsetSIMD integer type with offsets to the start of each triplet.
[out]v0First component, base[align*offset[i]] for each i.
[out]v1Second component, base[align*offset[i] + 1] for each i.

Since some SIMD architectures cannot handle any unaligned loads, this routine is only available if GMX_SIMD_HAVE_GATHER_LOADU_BYSIMDINT_TRANSPOSE is 1.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This is a special routine primarily intended for loading Gromacs table data as efficiently as possible - this is the reason for using a SIMD offset index, since the result of the real-to-integer conversion is present in a SIMD register just before calling this routine.
template<int align>
static void gmx_simdcall gmx::gatherLoadUBySimdIntTranspose ( const float *  base,
SimdFInt32  offset,
SimdFloat *  v0,
SimdFloat *  v1 
)
inlinestatic

Load 2 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets (unaligned) specified by SIMD integer, transpose into 2 SIMD floats.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 2 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
basePointer to the start of the memory.
offsetSIMD integer type with offsets to the start of each triplet.
[out]v0First component, base[align*offset[i]] for each i.
[out]v1Second component, base[align*offset[i] + 1] for each i.

Since some SIMD architectures cannot handle any unaligned loads, this routine is only available if GMX_SIMD_HAVE_GATHER_LOADU_BYSIMDINT_TRANSPOSE is 1.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This is a special routine primarily intended for loading Gromacs table data as efficiently as possible - this is the reason for using a SIMD offset index, since the result of the real-to-integer conversion is present in a SIMD register just before calling this routine.
template<int align>
static void gmx_simdcall gmx::gatherLoadUTranspose ( const double *  base,
const std::int32_t  offset[],
SimdDouble *  v0,
SimdDouble *  v1,
SimdDouble *  v2 
)
inlinestatic

Load 3 consecutive doubles from each of GMX_SIMD_DOUBLE_WIDTH offsets, and transpose into 3 SIMD double variables.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 3 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
basePointer to the start of the memory area
offsetArray with offsets to the start of each data point.
[out]v01st component of data, base[align*offset[i]] for each i.
[out]v12nd component of data, base[align*offset[i] + 1] for each i.
[out]v23rd component of data, base[align*offset[i] + 2] for each i.

This function can work with both aligned (better performance) and unaligned memory. When the align parameter is not a power-of-two (align==3 would be normal for packed atomic coordinates) the memory obviously cannot be aligned, and we account for this. However, in the case where align is a power-of-two, we assume the base pointer also has the same alignment, which will enable many platforms to use faster aligned memory load operations. An easy way to think of this is that each triplet of data in memory must be aligned to the align parameter you specify when it's a power-of-two.

The offset memory must always be aligned to GMX_SIMD_FINT32_WIDTH, since this enables us to use SIMD loads and gather operations on platforms that support it.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This routine uses a normal array for the offsets, since we typically load this data from memory. On the architectures we have tested this is faster even when a SIMD integer datatype is present.
To improve performance, this function might use full-SIMD-width unaligned loads. This means you need to ensure the memory is padded at the end, so we always can load GMX_SIMD_REAL_WIDTH elements starting at the last offset. If you use the Gromacs aligned memory allocation routines this will always be the case.
template<int align>
static void gmx_simdcall gmx::gatherLoadUTranspose ( const float *  base,
const std::int32_t  offset[],
SimdFloat *  v0,
SimdFloat *  v1,
SimdFloat *  v2 
)
inlinestatic

Load 3 consecutive floats from each of GMX_SIMD_FLOAT_WIDTH offsets, and transpose into 3 SIMD float variables.

Template Parameters
alignAlignment of the memory from which we read, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 3 for this routine) the input data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are loaded.
Parameters
basePointer to the start of the memory area
offsetArray with offsets to the start of each data point.
[out]v01st component of data, base[align*offset[i]] for each i.
[out]v12nd component of data, base[align*offset[i] + 1] for each i.
[out]v23rd component of data, base[align*offset[i] + 2] for each i.

This function can work with both aligned (better performance) and unaligned memory. When the align parameter is not a power-of-two (align==3 would be normal for packed atomic coordinates) the memory obviously cannot be aligned, and we account for this. However, in the case where align is a power-of-two, we assume the base pointer also has the same alignment, which will enable many platforms to use faster aligned memory load operations. An easy way to think of this is that each triplet of data in memory must be aligned to the align parameter you specify when it's a power-of-two.

The offset memory must always be aligned to GMX_SIMD_FINT32_WIDTH, since this enables us to use SIMD loads and gather operations on platforms that support it.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This routine uses a normal array for the offsets, since we typically load this data from memory. On the architectures we have tested this is faster even when a SIMD integer datatype is present.
To improve performance, this function might use full-SIMD-width unaligned loads. This means you need to ensure the memory is padded at the end, so we always can load GMX_SIMD_REAL_WIDTH elements starting at the last offset. If you use the Gromacs aligned memory allocation routines this will always be the case.
std::vector< real > gmx::test::SimdMathTest::generateTestPoints ( Range  range,
std::size_t  points 
)

Generate test point vector.

Parameters
rangeThe test interval, half open. Upper limit is not included. Pass by value, since we need to modify in method anyway.
pointsNumber of points to generate. This might be increased slightly to account both for extra special values like 0.0 and the SIMD width.

This routine generates a vector with test points separated by constant multiplicative factors, based on the range and number of points in the class. If the range includes both negative and positive values, points will be generated separately for the negative/positive intervals down to the smallest real number that can be represented, and we also include 0.0 explicitly.

This is highly useful for large test ranges. For example, with a linear 1000-point division of the range (1,1e10) the first three values to test would be 1, 10000000.999, and 20000000.998, etc. For large values we would commonly hit the point where adding the small delta has no effect due to limited numerical precision. When we instead use this routine, the values will be 1, 1.0239, 1.0471, etc. This will spread the entropy over all bits in the IEEE754 representation, and be a much better test of all potential input values.

Note
We do not use the static variable s_nPoints in the parent class to avoid altering any value the user has set on the command line; since it's a static member, changing it would have permanent effect.
static SimdFloat gmx_simdcall gmx::inv ( SimdFloat  x)
inlinestatic

Calculate 1/x for SIMD float.

Parameters
xArgument with magnitude larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/x. Result is undefined if your argument was invalid.
static SimdDouble gmx_simdcall gmx::inv ( SimdDouble  x)
inlinestatic

Calculate 1/x for SIMD double.

Parameters
xArgument with magnitude larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/x. Result is undefined if your argument was invalid.
static SimdFloat gmx_simdcall gmx::invcbrt ( SimdFloat  x)
inlinestatic

Inverse cube root for SIMD floats.

Parameters
xArgument to calculate cube root of. Can be positive or negative, but the magnitude cannot be lower than the smallest normal number.
Returns
Cube root of x. Undefined for values that don't fulfill the restriction of abs(x) > minFloat.
static SimdDouble gmx_simdcall gmx::invcbrt ( SimdDouble  x)
inlinestatic

Inverse cube root for SIMD doubles.

Parameters
xArgument to calculate cube root of. Can be positive or negative, but the magnitude cannot be lower than the smallest normal number.
Returns
Cube root of x. Undefined for values that don't fulfill the restriction of abs(x) > minDouble.
static SimdDouble gmx_simdcall gmx::invcbrtSingleAccuracy ( SimdDouble  x)
inlinestatic

Inverse cube root for SIMD doubles, single accuracy.

Parameters
xArgument to calculate cube root of. Can be positive or negative, but the magnitude cannot be lower than the smallest normal number.
Returns
Cube root of x. Undefined for values that don't fulfill the restriction of abs(x) > minDouble.
static SimdFloat gmx_simdcall gmx::invcbrtSingleAccuracy ( SimdFloat  x)
inlinestatic

Calculate 1/cbrt(x) for SIMD float, always targeting single accuracy.

Parameters
xArgument to calculate cube root of. Can be negative or zero, but NaN or Inf values are not supported. Denormal values will be treated as 0.0.
Returns
Cube root of x.
static SimdDouble gmx_simdcall gmx::invSingleAccuracy ( SimdDouble  x)
inlinestatic

Calculate 1/x for SIMD double, but in single accuracy.

Parameters
xArgument with magnitude larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/x. Result is undefined if your argument was invalid.
static SimdFloat gmx_simdcall gmx::invSingleAccuracy ( SimdFloat  x)
inlinestatic

Calculate 1/x for SIMD float, only targeting single accuracy.

Parameters
xArgument with magnitude larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/x. Result is undefined if your argument was invalid.
static SimdFloat gmx_simdcall gmx::invsqrt ( SimdFloat  x)
inlinestatic

Calculate 1/sqrt(x) for SIMD float.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/sqrt(x). Result is undefined if your argument was invalid.
static SimdDouble gmx_simdcall gmx::invsqrt ( SimdDouble  x)
inlinestatic

Calculate 1/sqrt(x) for SIMD double.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/sqrt(x). Result is undefined if your argument was invalid.
static Simd4Float gmx_simdcall gmx::invsqrt ( Simd4Float  x)
inlinestatic

Calculate 1/sqrt(x) for SIMD4 float.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/sqrt(x). Result is undefined if your argument was invalid.
static Simd4Double gmx_simdcall gmx::invsqrt ( Simd4Double  x)
inlinestatic

Calculate 1/sqrt(x) for SIMD4 double.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/sqrt(x). Result is undefined if your argument was invalid.
static void gmx_simdcall gmx::invsqrtPair ( SimdFloat  x0,
SimdFloat  x1,
SimdFloat *  out0,
SimdFloat *  out1 
)
inlinestatic

Calculate 1/sqrt(x) for two SIMD floats.

Parameters
x0First set of arguments, x0 must be in single range (see below).
x1Second set of arguments, x1 must be in single range (see below).
[out]out0Result 1/sqrt(x0)
[out]out1Result 1/sqrt(x1)

In particular for double precision we can sometimes calculate square root pairs slightly faster by using single precision until the very last step.

Note
Both arguments must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
static void gmx_simdcall gmx::invsqrtPair ( SimdDouble  x0,
SimdDouble  x1,
SimdDouble *  out0,
SimdDouble *  out1 
)
inlinestatic

Calculate 1/sqrt(x) for two SIMD doubles.

Parameters
x0First set of arguments, x0 must be in single range (see below).
x1Second set of arguments, x1 must be in single range (see below).
[out]out0Result 1/sqrt(x0)
[out]out1Result 1/sqrt(x1)

In particular for double precision we can sometimes calculate square root pairs slightly faster by using single precision until the very last step.

Note
Both arguments must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
static void gmx_simdcall gmx::invsqrtPairSingleAccuracy ( SimdDouble  x0,
SimdDouble  x1,
SimdDouble *  out0,
SimdDouble *  out1 
)
inlinestatic

Calculate 1/sqrt(x) for two SIMD doubles, but single accuracy.

Parameters
x0First set of arguments, x0 must be in single range (see below).
x1Second set of arguments, x1 must be in single range (see below).
[out]out0Result 1/sqrt(x0)
[out]out1Result 1/sqrt(x1)

In particular for double precision we can sometimes calculate square root pairs slightly faster by using single precision until the very last step.

Note
Both arguments must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
static void gmx_simdcall gmx::invsqrtPairSingleAccuracy ( SimdFloat  x0,
SimdFloat  x1,
SimdFloat *  out0,
SimdFloat *  out1 
)
inlinestatic

Calculate 1/sqrt(x) for two SIMD floats, only targeting single accuracy.

Parameters
x0First set of arguments, x0 must be in single range (see below).
x1Second set of arguments, x1 must be in single range (see below).
[out]out0Result 1/sqrt(x0)
[out]out1Result 1/sqrt(x1)

In particular for double precision we can sometimes calculate square root pairs slightly faster by using single precision until the very last step.

Note
Both arguments must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
static SimdDouble gmx_simdcall gmx::invsqrtSingleAccuracy ( SimdDouble  x)
inlinestatic

Calculate 1/sqrt(x) for SIMD double, but in single accuracy.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/sqrt(x). Result is undefined if your argument was invalid.
static Simd4Double gmx_simdcall gmx::invsqrtSingleAccuracy ( Simd4Double  x)
inlinestatic

Calculate 1/sqrt(x) for SIMD4 double, but in single accuracy.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/sqrt(x). Result is undefined if your argument was invalid.
static SimdFloat gmx_simdcall gmx::invsqrtSingleAccuracy ( SimdFloat  x)
inlinestatic

Calculate 1/sqrt(x) for SIMD float, only targeting single accuracy.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/sqrt(x). Result is undefined if your argument was invalid.
static Simd4Float gmx_simdcall gmx::invsqrtSingleAccuracy ( Simd4Float  x)
inlinestatic

Calculate 1/sqrt(x) for SIMD4 float, only targeting single accuracy.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
1/sqrt(x). Result is undefined if your argument was invalid.
static SimdFloat gmx_simdcall gmx::iprod ( SimdFloat  ax,
SimdFloat  ay,
SimdFloat  az,
SimdFloat  bx,
SimdFloat  by,
SimdFloat  bz 
)
inlinestatic

SIMD float inner product of multiple float vectors.

Parameters
axX components of first vectors
ayY components of first vectors
azZ components of first vectors
bxX components of second vectors
byY components of second vectors
bzZ components of second vectors
Returns
Element i will be res[i] = ax[i]*bx[i]+ay[i]*by[i]+az[i]*bz[i].
Note
The SIMD part is that we calculate many scalar products in one call.
static SimdDouble gmx_simdcall gmx::iprod ( SimdDouble  ax,
SimdDouble  ay,
SimdDouble  az,
SimdDouble  bx,
SimdDouble  by,
SimdDouble  bz 
)
inlinestatic

SIMD double inner product of multiple double vectors.

Parameters
axX components of first vectors
ayY components of first vectors
azZ components of first vectors
bxX components of second vectors
byY components of second vectors
bzZ components of second vectors
Returns
Element i will be res[i] = ax[i]*bx[i]+ay[i]*by[i]+az[i]*bz[i].
Note
The SIMD part is that we calculate many scalar products in one call.
static Simd4Float gmx_simdcall gmx::load4 ( const float *  m)
inlinestatic

Load 4 float values from aligned memory into SIMD4 variable.

Parameters
mPointer to memory aligned to 4 elements.
Returns
SIMD4 variable with data loaded.
static Simd4Double gmx_simdcall gmx::load4 ( const double *  m)
inlinestatic

Load 4 double values from aligned memory into SIMD4 variable.

Parameters
mPointer to memory aligned to 4 elements.
Returns
SIMD4 variable with data loaded.
static Simd4Float gmx_simdcall gmx::load4U ( const float *  m)
inlinestatic

Load SIMD4 float from unaligned memory.

Available if GMX_SIMD_HAVE_LOADU is 1.

Parameters
mPointer to memory, no alignment requirement.
Returns
SIMD4 variable with data loaded.
static Simd4Double gmx_simdcall gmx::load4U ( const double *  m)
inlinestatic

Load SIMD4 double from unaligned memory.

Available if GMX_SIMD_HAVE_LOADU is 1.

Parameters
mPointer to memory, no alignment requirement.
Returns
SIMD4 variable with data loaded.
template<typename T , typename TSimd , int simdWidth>
void gmx::test::anonymous_namespace{bootstrap_loadstore.cpp}::loadStoreTester ( TSimd gmx_simdcall   loadFnconst T *mem,
void gmx_simdcall   storeFnT *mem, TSimd,
const int  loadOffset,
const int  storeOffset 
)

Generic routine to test load & store of SIMD, and check for side effects.

The tests for load, store, unaligned load and unaligned store both for real and int are pretty much similar, so we use a template function with additional function pointers for the actual load/store calls.

template<typename T , typename TSimd >
TSimd gmx_simdcall gmx::test::anonymous_namespace{bootstrap_loadstore.cpp}::loadUWrapper ( const T *  m)

Wrapper to handle proxy objects returned by some loadU functions.

Template Parameters
TType of scalar object
TSimdCorresponding SIMD type
Parameters
mMemory address to load from
template<typename T , typename TSimd >
TSimd gmx_simdcall gmx::test::anonymous_namespace{bootstrap_loadstore.cpp}::loadWrapper ( const T *  m)

Wrapper to handle proxy objects returned by some load functions.

Template Parameters
TType of scalar object
TSimdCorresponding SIMD type
Parameters
mMemory address to load from
static SimdFloat gmx_simdcall gmx::log ( SimdFloat  x)
inlinestatic

SIMD float log(x). This is the natural logarithm.

Parameters
xArgument, should be >0.
Returns
The natural logarithm of x. Undefined if argument is invalid.
static SimdDouble gmx_simdcall gmx::log ( SimdDouble  x)
inlinestatic

SIMD double log(x). This is the natural logarithm.

Parameters
xArgument, should be >0.
Returns
The natural logarithm of x. Undefined if argument is invalid.
static SimdFloat gmx_simdcall gmx::log2 ( SimdFloat  x)
inlinestatic

SIMD float log2(x). This is the base-2 logarithm.

Parameters
xArgument, should be >0.
Returns
The base-2 logarithm of x. Undefined if argument is invalid.
static SimdDouble gmx_simdcall gmx::log2 ( SimdDouble  x)
inlinestatic

SIMD double log2(x). This is the base-2 logarithm.

Parameters
xArgument, should be >0.
Returns
The base-2 logarithm of x. Undefined if argument is invalid.
static SimdDouble gmx_simdcall gmx::log2SingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD log2(x). Double precision SIMD data, single accuracy.

Parameters
xArgument, should be >0.
Returns
The base 2 logarithm of x. Undefined if argument is invalid.
static SimdFloat gmx_simdcall gmx::log2SingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float log2(x), only targeting single accuracy. This is the base-2 logarithm.

Parameters
xArgument, should be >0.
Returns
The base-2 logarithm of x. Undefined if argument is invalid.
static SimdDouble gmx_simdcall gmx::logSingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD log(x). Double precision SIMD data, single accuracy.

Parameters
xArgument, should be >0.
Returns
The natural logarithm of x. Undefined if argument is invalid.
static SimdFloat gmx_simdcall gmx::logSingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float log(x), only targeting single accuracy. This is the natural logarithm.

Parameters
xArgument, should be >0.
Returns
The natural logarithm of x. Undefined if argument is invalid.
static SimdFloat gmx_simdcall gmx::maskzInv ( SimdFloat  x,
SimdFBool  m 
)
inlinestatic

Calculate 1/x for SIMD float, masked version.

Parameters
xArgument with magnitude larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX for masked-in entries. See invsqrt for the discussion about argument restrictions.
mMask
Returns
1/x for elements where m is true, or 0.0 for masked-out entries.
static SimdDouble gmx_simdcall gmx::maskzInv ( SimdDouble  x,
SimdDBool  m 
)
inlinestatic

Calculate 1/x for SIMD double, masked version.

Parameters
xArgument with magnitude larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX for masked-in entries. See invsqrt for the discussion about argument restrictions.
mMask
Returns
1/x for elements where m is true, or 0.0 for masked-out entries.
static SimdDouble gmx_simdcall gmx::maskzInvSingleAccuracy ( SimdDouble  x,
SimdDBool  m 
)
inlinestatic

1/x for masked entries of SIMD double, single accuracy.

Parameters
xArgument with magnitude larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
mMask
Returns
1/x for elements where m is true, or 0.0 for masked-out entries.
static SimdFloat gmx::maskzInvSingleAccuracy ( SimdFloat  x,
SimdFBool  m 
)
inlinestatic

Calculate 1/x for masked SIMD floats, only targeting single accuracy.

Parameters
xArgument with magnitude larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
mMask
Returns
1/x for elements where m is true, or 0.0 for masked-out entries.
static SimdFloat gmx::maskzInvsqrt ( SimdFloat  x,
SimdFBool  m 
)
inlinestatic

Calculate 1/sqrt(x) for masked entries of SIMD float.

This routine only evaluates 1/sqrt(x) for elements for which mask is true. Illegal values in the masked-out elements will not lead to floating-point exceptions.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX for masked-in entries. See invsqrt for the discussion about argument restrictions.
mMask
Returns
1/sqrt(x). Result is undefined if your argument was invalid or entry was not masked, and 0.0 for masked-out entries.
static SimdDouble gmx::maskzInvsqrt ( SimdDouble  x,
SimdDBool  m 
)
inlinestatic

Calculate 1/sqrt(x) for masked entries of SIMD double.

This routine only evaluates 1/sqrt(x) for elements for which mask is true. Illegal values in the masked-out elements will not lead to floating-point exceptions.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX for masked-in entries. See invsqrt for the discussion about argument restrictions.
mMask
Returns
1/sqrt(x). Result is undefined if your argument was invalid or entry was not masked, and 0.0 for masked-out entries.
static SimdDouble gmx::maskzInvsqrtSingleAccuracy ( SimdDouble  x,
SimdDBool  m 
)
inlinestatic

1/sqrt(x) for masked-in entries of SIMD double, but in single accuracy.

This routine only evaluates 1/sqrt(x) for elements for which mask is true. Illegal values in the masked-out elements will not lead to floating-point exceptions.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
mMask
Returns
1/sqrt(x). Result is undefined if your argument was invalid or entry was not masked, and 0.0 for masked-out entries.
static SimdFloat gmx::maskzInvsqrtSingleAccuracy ( SimdFloat  x,
SimdFBool  m 
)
inlinestatic

Calculate 1/sqrt(x) for masked SIMD floats, only targeting single accuracy.

This routine only evaluates 1/sqrt(x) for elements for which mask is true. Illegal values in the masked-out elements will not lead to floating-point exceptions.

Parameters
xArgument that must be larger than GMX_FLOAT_MIN and smaller than GMX_FLOAT_MAX, i.e. within the range of single precision. For the single precision implementation this is obviously always true for positive values, but for double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
mMask
Returns
1/sqrt(x). Result is undefined if your argument was invalid or entry was not masked, and 0.0 for masked-out entries.
static Simd4Float gmx_simdcall gmx::max ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

Set each SIMD4 element to the largest from two variables.

Parameters
aAny floating-point value
bAny floating-point value
Returns
max(a,b) for each element.
static Simd4Double gmx_simdcall gmx::max ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

Set each SIMD4 element to the largest from two variables.

Parameters
aAny floating-point value
bAny floating-point value
Returns
max(a,b) for each element.
static Simd4Float gmx_simdcall gmx::min ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

Set each SIMD4 element to the largest from two variables.

Parameters
aAny floating-point value
bAny floating-point value
Returns
max(a,b) for each element.
static Simd4Double gmx_simdcall gmx::min ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

Set each SIMD4 element to the largest from two variables.

Parameters
aAny floating-point value
bAny floating-point value
Returns
max(a,b) for each element.
static SimdFloat gmx_simdcall gmx::norm2 ( SimdFloat  ax,
SimdFloat  ay,
SimdFloat  az 
)
inlinestatic

SIMD float norm squared of multiple vectors.

Parameters
axX components of vectors
ayY components of vectors
azZ components of vectors
Returns
Element i will be res[i] = ax[i]*ax[i]+ay[i]*ay[i]+az[i]*az[i].
Note
This corresponds to the scalar product of the vector with itself, but the compiler might be able to optimize it better with identical vectors.
static SimdDouble gmx_simdcall gmx::norm2 ( SimdDouble  ax,
SimdDouble  ay,
SimdDouble  az 
)
inlinestatic

SIMD double norm squared of multiple vectors.

Parameters
axX components of vectors
ayY components of vectors
azZ components of vectors
Returns
Element i will be res[i] = ax[i]*ax[i]+ay[i]*ay[i]+az[i]*az[i].
Note
This corresponds to the scalar product of the vector with itself, but the compiler might be able to optimize it better with identical vectors.
static Simd4Float gmx_simdcall gmx::norm2 ( Simd4Float  ax,
Simd4Float  ay,
Simd4Float  az 
)
inlinestatic

SIMD4 float norm squared of multiple vectors.

Parameters
axX components of vectors
ayY components of vectors
azZ components of vectors
Returns
Element i will be res[i] = ax[i]*ax[i]+ay[i]*ay[i]+az[i]*az[i].
Note
This corresponds to the scalar product of the vector with itself, but the compiler might be able to optimize it better with identical vectors.
static Simd4Double gmx_simdcall gmx::norm2 ( Simd4Double  ax,
Simd4Double  ay,
Simd4Double  az 
)
inlinestatic

SIMD4 double norm squared of multiple vectors.

Parameters
axX components of vectors
ayY components of vectors
azZ components of vectors
Returns
Element i will be res[i] = ax[i]*ax[i]+ay[i]*ay[i]+az[i]*az[i].
Note
This corresponds to the scalar product of the vector with itself, but the compiler might be able to optimize it better with identical vectors.
static Simd4FBool gmx_simdcall gmx::operator!= ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

a!=b for SIMD4 float

Parameters
avalue1
bvalue2
Returns
Each element of the boolean will be set to true if a!=b.
static Simd4DBool gmx_simdcall gmx::operator!= ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

a!=b for SIMD4 double

Parameters
avalue1
bvalue2
Returns
Each element of the boolean will be set to true if a!=b.
static Simd4Double gmx_simdcall gmx::operator& ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

Bitwise and for two SIMD4 double variables.

Supported if GMX_SIMD_HAVE_LOGICAL is 1.

Parameters
adata1
bdata2
Returns
data1 & data2
static Simd4Float gmx_simdcall gmx::operator& ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

Bitwise and for two SIMD4 float variables.

Supported if GMX_SIMD_HAVE_LOGICAL is 1.

Parameters
adata1
bdata2
Returns
data1 & data2
static Simd4FBool gmx_simdcall gmx::operator&& ( Simd4FBool  a,
Simd4FBool  b 
)
inlinestatic

Logical and on single precision SIMD4 booleans.

Parameters
alogical vars 1
blogical vars 2
Returns
For each element, the result boolean is true if a & b are true.
Note
This is not necessarily a bitwise operation - the storage format of booleans is implementation-dependent.
static Simd4DBool gmx_simdcall gmx::operator&& ( Simd4DBool  a,
Simd4DBool  b 
)
inlinestatic

Logical and on single precision SIMD4 booleans.

Parameters
alogical vars 1
blogical vars 2
Returns
For each element, the result boolean is true if a & b are true.
Note
This is not necessarily a bitwise operation - the storage format of booleans is implementation-dependent.
static Simd4Float gmx_simdcall gmx::operator* ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

Multiply two SIMD4 variables.

Parameters
afactor1
bfactor2
Returns
a*b.
static Simd4Double gmx_simdcall gmx::operator* ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

Multiply two SIMD4 variables.

Parameters
afactor1
bfactor2
Returns
a*b.
static Simd4Double gmx_simdcall gmx::operator+ ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

Add two double SIMD4 variables.

Parameters
aterm1
bterm2
Returns
a+b
static Simd4Float gmx_simdcall gmx::operator+ ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

Add two float SIMD4 variables.

Parameters
aterm1
bterm2
Returns
a+b
static Simd4Float gmx_simdcall gmx::operator- ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

Subtract two SIMD4 variables.

Parameters
aterm1
bterm2
Returns
a-b
static Simd4Double gmx_simdcall gmx::operator- ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

Subtract two SIMD4 variables.

Parameters
aterm1
bterm2
Returns
a-b
static Simd4Float gmx_simdcall gmx::operator- ( Simd4Float  a)
inlinestatic

SIMD4 floating-point negate.

Parameters
aSIMD4 floating-point value
Returns
-a
static Simd4Double gmx_simdcall gmx::operator- ( Simd4Double  a)
inlinestatic

SIMD4 floating-point negate.

Parameters
aSIMD4 floating-point value
Returns
-a
static SimdFloat gmx_simdcall gmx::operator/ ( SimdFloat  nom,
SimdFloat  denom 
)
inlinestatic

Division for SIMD floats.

Parameters
nomNominator
denomDenominator, with magnitude in range (GMX_FLOAT_MIN,GMX_FLOAT_MAX). For single precision this is equivalent to a nonzero argument, but in double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
nom/denom
Note
This function does not use any masking to avoid problems with zero values in the denominator.
static SimdDouble gmx_simdcall gmx::operator/ ( SimdDouble  nom,
SimdDouble  denom 
)
inlinestatic

Division for SIMD doubles.

Parameters
nomNominator
denomDenominator, with magnitude in range (GMX_FLOAT_MIN,GMX_FLOAT_MAX). For single precision this is equivalent to a nonzero argument, but in double precision it adds an extra restriction since the first lookup step might have to be performed in single precision on some architectures. Note that the responsibility for checking falls on you - this routine does not check arguments.
Returns
nom/denom
Note
This function does not use any masking to avoid problems with zero values in the denominator.
static Simd4FBool gmx_simdcall gmx::operator< ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

a<b for SIMD4 float

Parameters
avalue1
bvalue2
Returns
Each element of the boolean will be set to true if a<b.
static Simd4DBool gmx_simdcall gmx::operator< ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

a<b for SIMD4 double

Parameters
avalue1
bvalue2
Returns
Each element of the boolean will be set to true if a<b.
static Simd4FBool gmx_simdcall gmx::operator<= ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

a<=b for SIMD4 float.

Parameters
avalue1
bvalue2
Returns
Each element of the boolean will be set to true if a<=b.
static Simd4DBool gmx_simdcall gmx::operator<= ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

a<=b for SIMD4 double.

Parameters
avalue1
bvalue2
Returns
Each element of the boolean will be set to true if a<=b.
static Simd4FBool gmx_simdcall gmx::operator== ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

a==b for SIMD4 float

Parameters
avalue1
bvalue2
Returns
Each element of the boolean will be set to true if a==b.
static Simd4DBool gmx_simdcall gmx::operator== ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

a==b for SIMD4 double

Parameters
avalue1
bvalue2
Returns
Each element of the boolean will be set to true if a==b.
static Simd4Float gmx_simdcall gmx::operator^ ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

Bitwise xor for two SIMD4 float variables.

Available if GMX_SIMD_HAVE_LOGICAL is 1.

Parameters
adata1
bdata2
Returns
data1 ^ data2
static Simd4Double gmx_simdcall gmx::operator^ ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

Bitwise xor for two SIMD4 double variables.

Available if GMX_SIMD_HAVE_LOGICAL is 1.

Parameters
adata1
bdata2
Returns
data1 ^ data2
static Simd4Double gmx_simdcall gmx::operator| ( Simd4Double  a,
Simd4Double  b 
)
inlinestatic

Bitwise or for two SIMD4 doubles.

Available if GMX_SIMD_HAVE_LOGICAL is 1.

Parameters
adata1
bdata2
Returns
data1 | data2
static Simd4Float gmx_simdcall gmx::operator| ( Simd4Float  a,
Simd4Float  b 
)
inlinestatic

Bitwise or for two SIMD4 floats.

Available if GMX_SIMD_HAVE_LOGICAL is 1.

Parameters
adata1
bdata2
Returns
data1 | data2
static Simd4FBool gmx_simdcall gmx::operator|| ( Simd4FBool  a,
Simd4FBool  b 
)
inlinestatic

Logical or on single precision SIMD4 booleans.

Parameters
alogical vars 1
blogical vars 2
Returns
For each element, the result boolean is true if a or b is true.

Note that this is not necessarily a bitwise operation - the storage format of booleans is implementation-dependent.

static Simd4DBool gmx_simdcall gmx::operator|| ( Simd4DBool  a,
Simd4DBool  b 
)
inlinestatic

Logical or on single precision SIMD4 booleans.

Parameters
alogical vars 1
blogical vars 2
Returns
For each element, the result boolean is true if a or b is true.

Note that this is not necessarily a bitwise operation - the storage format of booleans is implementation-dependent.

static SimdFloat gmx_simdcall gmx::pmeForceCorrection ( SimdFloat  z2)
inlinestatic

Calculate the force correction due to PME analytically in SIMD float.

Parameters
z2$(r \beta)^2$ - see below for details.
Returns
Correction factor to coulomb force - see below for details.

This routine is meant to enable analytical evaluation of the direct-space PME electrostatic force to avoid tables.

The direct-space potential should be $ \mbox{erfc}(\beta r)/r$, but there are some problems evaluating that:

First, the error function is difficult (read: expensive) to approxmiate accurately for intermediate to large arguments, and this happens already in ranges of $(\beta r)$ that occur in simulations. Second, we now try to avoid calculating potentials in Gromacs but use forces directly.

We can simply things slight by noting that the PME part is really a correction to the normal Coulomb force since $\mbox{erfc}(z)=1-\mbox{erf}(z)$, i.e.

\[ V = \frac{1}{r} - \frac{\mbox{erf}(\beta r)}{r} \]

The first term we already have from the inverse square root, so that we can leave out of this routine.

For pme tolerances of 1e-3 to 1e-8 and cutoffs of 0.5nm to 1.8nm, the argument $beta r$ will be in the range 0.15 to ~4, which is the range used for the minimax fit. Use your favorite plotting program to realize how well-behaved $\frac{\mbox{erf}(z)}{z}$ is in this range!

We approximate $f(z)=\mbox{erf}(z)/z$ with a rational minimax polynomial. However, it turns out it is more efficient to approximate $f(z)/z$ and then only use even powers. This is another minor optimization, since we actually want $f(z)/z$, because it is going to be multiplied by the vector between the two atoms to get the vectorial force. The fastest flops are the ones we can avoid calculating!

So, here's how it should be used:

  1. Calculate $r^2$.
  2. Multiply by $\beta^2$, so you get $z^2=(\beta r)^2$.
  3. Evaluate this routine with $z^2$ as the argument.
  4. The return value is the expression:

    \[ \frac{2 \exp{-z^2}}{\sqrt{\pi} z^2}-\frac{\mbox{erf}(z)}{z^3} \]

  5. Multiply the entire expression by $\beta^3$. This will get you

    \[ \frac{2 \beta^3 \exp(-z^2)}{\sqrt{\pi} z^2} - \frac{\beta^3 \mbox{erf}(z)}{z^3} \]

    or, switching back to $r$ (since $z=r \beta$):

    \[ \frac{2 \beta \exp(-r^2 \beta^2)}{\sqrt{\pi} r^2} - \frac{\mbox{erf}(r \beta)}{r^3} \]

    With a bit of math exercise you should be able to confirm that this is exactly

    \[ \frac{\frac{d}{dr}\left( \frac{\mbox{erf}(\beta r)}{r} \right)}{r} \]

  6. Add the result to $r^{-3}$, multiply by the product of the charges, and you have your force (divided by $r$). A final multiplication with the vector connecting the two particles and you have your vectorial force to add to the particles.

This approximation achieves an error slightly lower than 1e-6 in single precision and 1e-11 in double precision for arguments smaller than 16 ( $\beta r \leq 4 $); when added to $1/r$ the error will be insignificant. For $\beta r \geq 7206$ the return value can be inf or NaN.

static SimdDouble gmx_simdcall gmx::pmeForceCorrection ( SimdDouble  z2)
inlinestatic

Calculate the force correction due to PME analytically in SIMD double.

Parameters
z2This should be the value $(r \beta)^2$, where r is your interaction distance and beta the ewald splitting parameters.
Returns
Correction factor to coulomb force.

This routine is meant to enable analytical evaluation of the direct-space PME electrostatic force to avoid tables. For details, see the single precision function.

static SimdDouble gmx_simdcall gmx::pmeForceCorrectionSingleAccuracy ( SimdDouble  z2)
inlinestatic

Analytical PME force correction, double SIMD data, single accuracy.

Parameters
z2$(r \beta)^2$ - see below for details.
Returns
Correction factor to coulomb force - see below for details.

This routine is meant to enable analytical evaluation of the direct-space PME electrostatic force to avoid tables.

The direct-space potential should be $ \mbox{erfc}(\beta r)/r$, but there are some problems evaluating that:

First, the error function is difficult (read: expensive) to approxmiate accurately for intermediate to large arguments, and this happens already in ranges of $(\beta r)$ that occur in simulations. Second, we now try to avoid calculating potentials in Gromacs but use forces directly.

We can simply things slight by noting that the PME part is really a correction to the normal Coulomb force since $\mbox{erfc}(z)=1-\mbox{erf}(z)$, i.e.

\[ V = \frac{1}{r} - \frac{\mbox{erf}(\beta r)}{r} \]

The first term we already have from the inverse square root, so that we can leave out of this routine.

For pme tolerances of 1e-3 to 1e-8 and cutoffs of 0.5nm to 1.8nm, the argument $beta r$ will be in the range 0.15 to ~4. Use your favorite plotting program to realize how well-behaved $\frac{\mbox{erf}(z)}{z}$ is in this range!

We approximate $f(z)=\mbox{erf}(z)/z$ with a rational minimax polynomial. However, it turns out it is more efficient to approximate $f(z)/z$ and then only use even powers. This is another minor optimization, since we actually want $f(z)/z$, because it is going to be multiplied by the vector between the two atoms to get the vectorial force. The fastest flops are the ones we can avoid calculating!

So, here's how it should be used:

  1. Calculate $r^2$.
  2. Multiply by $\beta^2$, so you get $z^2=(\beta r)^2$.
  3. Evaluate this routine with $z^2$ as the argument.
  4. The return value is the expression:

    \[ \frac{2 \exp{-z^2}}{\sqrt{\pi} z^2}-\frac{\mbox{erf}(z)}{z^3} \]

  5. Multiply the entire expression by $\beta^3$. This will get you

    \[ \frac{2 \beta^3 \exp(-z^2)}{\sqrt{\pi} z^2} - \frac{\beta^3 \mbox{erf}(z)}{z^3} \]

    or, switching back to $r$ (since $z=r \beta$):

    \[ \frac{2 \beta \exp(-r^2 \beta^2)}{\sqrt{\pi} r^2} - \frac{\mbox{erf}(r \beta)}{r^3} \]

    With a bit of math exercise you should be able to confirm that this is exactly

    \[ \frac{\frac{d}{dr}\left( \frac{\mbox{erf}(\beta r)}{r} \right)}{r} \]

  6. Add the result to $r^{-3}$, multiply by the product of the charges, and you have your force (divided by $r$). A final multiplication with the vector connecting the two particles and you have your vectorial force to add to the particles.

This approximation achieves an accuracy slightly lower than 1e-6; when added to $1/r$ the error will be insignificant.

static SimdFloat gmx_simdcall gmx::pmeForceCorrectionSingleAccuracy ( SimdFloat  z2)
inlinestatic

SIMD Analytic PME force correction, only targeting single accuracy.

Parameters
z2$(r \beta)^2$ - see default single precision version for details.
Returns
Correction factor to coulomb force.
static SimdFloat gmx_simdcall gmx::pmePotentialCorrection ( SimdFloat  z2)
inlinestatic

Calculate the potential correction due to PME analytically in SIMD float.

Parameters
z2$(r \beta)^2$ - see below for details.
Returns
Correction factor to coulomb potential - see below for details.

See pmeForceCorrection for details about the approximation.

This routine calculates $\mbox{erf}(z)/z$, although you should provide $z^2$ as the input argument.

Here's how it should be used:

  1. Calculate $r^2$.
  2. Multiply by $\beta^2$, so you get $z^2=\beta^2*r^2$.
  3. Evaluate this routine with z^2 as the argument.
  4. The return value is the expression:

    \[ \frac{\mbox{erf}(z)}{z} \]

  5. Multiply the entire expression by beta and switching back to $r$ (since $z=r \beta$):

    \[ \frac{\mbox{erf}(r \beta)}{r} \]

  6. Subtract the result from $1/r$, multiply by the product of the charges, and you have your potential.

This approximation achieves an error slightly lower than 1e-6 in single precision and 4e-11 in double precision for arguments smaller than 16 ( $ 0.15 \leq \beta r \leq 4 $); for $ \beta r \leq 0.15$ the error can be twice as high; when added to $1/r$ the error will be insignificant. For $\beta r \geq 7142$ the return value can be inf or NaN.

static SimdDouble gmx_simdcall gmx::pmePotentialCorrection ( SimdDouble  z2)
inlinestatic

Calculate the potential correction due to PME analytically in SIMD double.

Parameters
z2This should be the value $(r \beta)^2$, where r is your interaction distance and beta the ewald splitting parameters.
Returns
Correction factor to coulomb force.

This routine is meant to enable analytical evaluation of the direct-space PME electrostatic potential to avoid tables. For details, see the single precision function.

static SimdDouble gmx_simdcall gmx::pmePotentialCorrectionSingleAccuracy ( SimdDouble  z2)
inlinestatic

Analytical PME potential correction, double SIMD data, single accuracy.

Parameters
z2$(r \beta)^2$ - see below for details.
Returns
Correction factor to coulomb potential - see below for details.

This routine calculates $\mbox{erf}(z)/z$, although you should provide $z^2$ as the input argument.

Here's how it should be used:

  1. Calculate $r^2$.
  2. Multiply by $\beta^2$, so you get $z^2=\beta^2*r^2$.
  3. Evaluate this routine with z^2 as the argument.
  4. The return value is the expression:

    \[ \frac{\mbox{erf}(z)}{z} \]

  5. Multiply the entire expression by beta and switching back to $r$ (since $z=r \beta$):

    \[ \frac{\mbox{erf}(r \beta)}{r} \]

  6. Subtract the result from $1/r$, multiply by the product of the charges, and you have your potential.

This approximation achieves an accuracy slightly lower than 1e-6; when added to $1/r$ the error will be insignificant.

static SimdFloat gmx_simdcall gmx::pmePotentialCorrectionSingleAccuracy ( SimdFloat  z2)
inlinestatic

SIMD Analytic PME potential correction, only targeting single accuracy.

Parameters
z2$(r \beta)^2$ - see default single precision version for details.
Returns
Correction factor to coulomb force.
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::pow ( SimdFloat  x,
SimdFloat  y 
)
inlinestatic

SIMD float pow(x,y)

This returns x^y for SIMD values.

Template Parameters
optIf this is changed from the default (safe) into the unsafe option, there are no guarantees about correct results for x==0.
Parameters
xBase.
yexponent.
Returns
x^y. Overflowing arguments are likely to either return 0 or inf, depending on the underlying implementation. If unsafe optimizations are enabled, this is also true for x==0.
Warning
You cannot rely on this implementation returning inf for arguments that cause overflow. If you have some very large values and need to rely on getting a valid numerical output, take the minimum of your variable and the largest valid argument before calling this routine.
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::pow ( SimdDouble  x,
SimdDouble  y 
)
inlinestatic

SIMD double pow(x,y)

This returns x^y for SIMD values.

Template Parameters
optIf this is changed from the default (safe) into the unsafe option, there are no guarantees about correct results for x==0.
Parameters
xBase.
yexponent.
Returns
x^y. Overflowing arguments are likely to either return 0 or inf, depending on the underlying implementation. If unsafe optimizations are enabled, this is also true for x==0.
Warning
You cannot rely on this implementation returning inf for arguments that cause overflow. If you have some very large values and need to rely on getting a valid numerical output, take the minimum of your variable and the largest valid argument before calling this routine.
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::powSingleAccuracy ( SimdDouble  x,
SimdDouble  y 
)
inlinestatic

SIMD pow(x,y). Double precision SIMD data, single accuracy.

This returns x^y for SIMD values.

Template Parameters
optIf this is changed from the default (safe) into the unsafe option, there are no guarantees about correct results for x==0.
Parameters
xBase.
yexponent.
Returns
x^y. Overflowing arguments are likely to either return 0 or inf, depending on the underlying implementation. If unsafe optimizations are enabled, this is also true for x==0.
Warning
You cannot rely on this implementation returning inf for arguments that cause overflow. If you have some very large values and need to rely on getting a valid numerical output, take the minimum of your variable and the largest valid argument before calling this routine.
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::powSingleAccuracy ( SimdFloat  x,
SimdFloat  y 
)
inlinestatic

SIMD pow(x,y), only targeting single accuracy.

static SimdFloat gmx_simdcall gmx::rcpIter ( SimdFloat  lu,
SimdFloat  x 
)
inlinestatic

Perform one Newton-Raphson iteration to improve 1/x for SIMD float.

This is a low-level routine that should only be used by SIMD math routine that evaluates the reciprocal.

Parameters
luApproximation of 1/x, typically obtained from lookup.
xThe reference (starting) value x for which we want 1/x.
Returns
An improved approximation with roughly twice as many bits of accuracy.
static SimdDouble gmx_simdcall gmx::rcpIter ( SimdDouble  lu,
SimdDouble  x 
)
inlinestatic

Perform one Newton-Raphson iteration to improve 1/x for SIMD double.

This is a low-level routine that should only be used by SIMD math routine that evaluates the reciprocal.

Parameters
luApproximation of 1/x, typically obtained from lookup.
xThe reference (starting) value x for which we want 1/x.
Returns
An improved approximation with roughly twice as many bits of accuracy.
static float gmx_simdcall gmx::reduce ( Simd4Float  a)
inlinestatic

Return sum of all elements in SIMD4 float variable.

Parameters
aSIMD4 variable to reduce/sum.
Returns
The sum of all elements in the argument variable.
static double gmx_simdcall gmx::reduce ( Simd4Double  a)
inlinestatic

Return sum of all elements in SIMD4 double variable.

Parameters
aSIMD4 variable to reduce/sum.
Returns
The sum of all elements in the argument variable.
static double gmx_simdcall gmx::reduceIncr4ReturnSum ( double *  m,
SimdDouble  v0,
SimdDouble  v1,
SimdDouble  v2,
SimdDouble  v3 
)
inlinestatic

Reduce each of four SIMD doubles, add those values to four consecutive doubles in memory, return sum.

Parameters
mPointer to memory where four doubles should be incremented
v0SIMD variable whose sum should be added to m[0]
v1SIMD variable whose sum should be added to m[1]
v2SIMD variable whose sum should be added to m[2]
v3SIMD variable whose sum should be added to m[3]
Returns
Sum of all elements in the four SIMD variables.

The pointer m must be aligned to the smaller of four elements and the floating-point SIMD width.

Note
This is a special routine intended for the Gromacs nonbonded kernels. It is used in the epilogue of the outer loop, where the variables will contain unrolled forces for one outer-loop-particle each, corresponding to a single coordinate (i.e, say, four x-coordinate force variables). These should be summed and added to the force array in memory. Since we always work with contiguous SIMD-layout , we can use efficient aligned loads/stores. When calculating the virial, we also need the total sum of all forces for each coordinate. This is provided as the return value. For routines that do not need these, this extra code will be optimized away completely if you just ignore the return value (Checked with gcc-4.9.1 and clang-3.6 for AVX).
static float gmx_simdcall gmx::reduceIncr4ReturnSum ( float *  m,
SimdFloat  v0,
SimdFloat  v1,
SimdFloat  v2,
SimdFloat  v3 
)
inlinestatic

Reduce each of four SIMD floats, add those values to four consecutive floats in memory, return sum.

Parameters
mPointer to memory where four floats should be incremented
v0SIMD variable whose sum should be added to m[0]
v1SIMD variable whose sum should be added to m[1]
v2SIMD variable whose sum should be added to m[2]
v3SIMD variable whose sum should be added to m[3]
Returns
Sum of all elements in the four SIMD variables.

The pointer m must be aligned to the smaller of four elements and the floating-point SIMD width.

Note
This is a special routine intended for the Gromacs nonbonded kernels. It is used in the epilogue of the outer loop, where the variables will contain unrolled forces for one outer-loop-particle each, corresponding to a single coordinate (i.e, say, four x-coordinate force variables). These should be summed and added to the force array in memory. Since we always work with contiguous SIMD-layout , we can use efficient aligned loads/stores. When calculating the virial, we also need the total sum of all forces for each coordinate. This is provided as the return value. For routines that do not need these, this extra code will be optimized away completely if you just ignore the return value (Checked with gcc-4.9.1 and clang-3.6 for AVX).
real gmx::test::anonymous_namespace{simd_math.cpp}::refErf ( real  x)

Function wrapper for erf(x), with argument/return in default Gromacs precision.

Note
Single-precision erf() in some libraries can be slightly lower precision than the SIMD flavor, so we use a cast to force double precision for reference.
real gmx::test::anonymous_namespace{simd_math.cpp}::refErfc ( real  x)

Function wrapper for erfc(x), with argument/return in default Gromacs precision.

Note
Single-precision erfc() in some libraries can be slightly lower precision than the SIMD flavor, so we use a cast to force double precision for reference.
static Simd4Float gmx_simdcall gmx::round ( Simd4Float  a)
inlinestatic

SIMD4 Round to nearest integer value (in floating-point format).

Parameters
aAny floating-point value
Returns
The nearest integer, represented in floating-point format.
static Simd4Double gmx_simdcall gmx::round ( Simd4Double  a)
inlinestatic

SIMD4 Round to nearest integer value (in floating-point format).

Parameters
aAny floating-point value
Returns
The nearest integer, represented in floating-point format.
static Simd4Double gmx_simdcall gmx::rsqrt ( Simd4Double  x)
inlinestatic

SIMD4 1.0/sqrt(x) lookup.

This is a low-level instruction that should only be called from routines implementing the inverse square root in simd_math.h.

Parameters
xArgument, x>0
Returns
Approximation of 1/sqrt(x), accuracy is GMX_SIMD_RSQRT_BITS.
static Simd4Float gmx_simdcall gmx::rsqrt ( Simd4Float  x)
inlinestatic

SIMD4 1.0/sqrt(x) lookup.

This is a low-level instruction that should only be called from routines implementing the inverse square root in simd_math.h.

Parameters
xArgument, x>0
Returns
Approximation of 1/sqrt(x), accuracy is GMX_SIMD_RSQRT_BITS.
static SimdFloat gmx_simdcall gmx::rsqrtIter ( SimdFloat  lu,
SimdFloat  x 
)
inlinestatic

Perform one Newton-Raphson iteration to improve 1/sqrt(x) for SIMD float.

This is a low-level routine that should only be used by SIMD math routine that evaluates the inverse square root.

Parameters
luApproximation of 1/sqrt(x), typically obtained from lookup.
xThe reference (starting) value x for which we want 1/sqrt(x).
Returns
An improved approximation with roughly twice as many bits of accuracy.
static SimdDouble gmx_simdcall gmx::rsqrtIter ( SimdDouble  lu,
SimdDouble  x 
)
inlinestatic

Perform one Newton-Raphson iteration to improve 1/sqrt(x) for SIMD double.

This is a low-level routine that should only be used by SIMD math routine that evaluates the inverse square root.

Parameters
luApproximation of 1/sqrt(x), typically obtained from lookup.
xThe reference (starting) value x for which we want 1/sqrt(x).
Returns
An improved approximation with roughly twice as many bits of accuracy.
static Simd4Float gmx_simdcall gmx::rsqrtIter ( Simd4Float  lu,
Simd4Float  x 
)
inlinestatic

Perform one Newton-Raphson iteration to improve 1/sqrt(x) for SIMD4 float.

This is a low-level routine that should only be used by SIMD math routine that evaluates the inverse square root.

Parameters
luApproximation of 1/sqrt(x), typically obtained from lookup.
xThe reference (starting) value x for which we want 1/sqrt(x).
Returns
An improved approximation with roughly twice as many bits of accuracy.
static Simd4Double gmx_simdcall gmx::rsqrtIter ( Simd4Double  lu,
Simd4Double  x 
)
inlinestatic

Perform one Newton-Raphson iteration to improve 1/sqrt(x) for SIMD4 double.

This is a low-level routine that should only be used by SIMD math routine that evaluates the inverse square root.

Parameters
luApproximation of 1/sqrt(x), typically obtained from lookup.
xThe reference (starting) value x for which we want 1/sqrt(x).
Returns
An improved approximation with roughly twice as many bits of accuracy.
static Simd4Float gmx_simdcall gmx::selectByMask ( Simd4Float  a,
Simd4FBool  mask 
)
inlinestatic

Select from single precision SIMD4 variable where boolean is true.

Parameters
aFloating-point variable to select from
maskBoolean selector
Returns
For each element, a is selected for true, 0 for false.
static Simd4Double gmx_simdcall gmx::selectByMask ( Simd4Double  a,
Simd4DBool  mask 
)
inlinestatic

Select from single precision SIMD4 variable where boolean is true.

Parameters
aFloating-point variable to select from
maskBoolean selector
Returns
For each element, a is selected for true, 0 for false.
static Simd4Float gmx_simdcall gmx::selectByNotMask ( Simd4Float  a,
Simd4FBool  mask 
)
inlinestatic

Select from single precision SIMD4 variable where boolean is false.

Parameters
aFloating-point variable to select from
maskBoolean selector
Returns
For each element, a is selected for false, 0 for true (sic).
static Simd4Double gmx_simdcall gmx::selectByNotMask ( Simd4Double  a,
Simd4DBool  mask 
)
inlinestatic

Select from single precision SIMD4 variable where boolean is false.

Parameters
aFloating-point variable to select from
maskBoolean selector
Returns
For each element, a is selected for false, 0 for true (sic).
Simd4Real gmx::test::setSimd4RealFrom1R ( real  value)

Set SIMD4 register contents from single real value.

All elements is set from the given value. This is effectively the same operation as simd4Set1(), but is implemented using only load/store operations that have been tested separately in the bootstrapping tests.

Simd4Real gmx::test::setSimd4RealFrom3R ( real  r0,
real  r1,
real  r2 
)

Set SIMD4 register contents from three real values.

It might seem stupid to use three values when we know that the SIMD4 width is 4, but it simplifies the test organization when the SIMD and SIMD4 tests are completely symmetric.

SimdInt32 gmx::test::setSimdIntFrom1I ( int  value)

Set SIMD register contents from single integer value.

All elements is set from the given value. This is effectively the same operation as simdSet1I(), but is implemented using only load/store operations that have been tested separately in the bootstrapping tests.

SimdInt32 gmx::test::setSimdIntFrom3I ( int  i0,
int  i1,
int  i2 
)

Set SIMD register contents from three int values.

Our reason for using three values is that 3 is not a factor in any known SIMD width, so this way there will not be any simple repeated patterns e.g. between the low/high 64/128/256 bits in the SIMD register, which could hide bugs.

SimdReal gmx::test::setSimdRealFrom1R ( real  value)

Set SIMD register contents from single real value.

All elements is set from the given value. This is effectively the same operation as simdSet1(), but is implemented using only load/store operations that have been tested separately in the bootstrapping tests.

SimdReal gmx::test::setSimdRealFrom3R ( real  r0,
real  r1,
real  r2 
)

Set SIMD register contents from three real values.

Our reason for using three values is that 3 is not a factor in any known SIMD width, so this way there will not be any simple repeated patterns e.g. between the low/high 64/128/256 bits in the SIMD register, which could hide bugs.

std::vector< real > gmx::test::simd4Real2Vector ( Simd4Real  simd4)

Convert SIMD4 real to std::vector<real>.

The returned vector will have the same length as the SIMD4 width.

static Simd4Double gmx_simdcall gmx::simd4SetZeroD ( )
inlinestatic

Set all SIMD4 double elements to 0.

You should typically just call gmx::setZero(), which uses proxy objects internally to handle all types rather than adding the suffix used here.

Returns
SIMD4 0.0
static Simd4Float gmx_simdcall gmx::simd4SetZeroF ( )
inlinestatic

Set all SIMD4 float elements to 0.

You should typically just call gmx::setZero(), which uses proxy objects internally to handle all types rather than adding the suffix used here.

Returns
SIMD4 0.0
std::vector< std::int32_t > gmx::test::simdInt2Vector ( SimdInt32  simd)

Convert SIMD integer to std::vector<int>.

The returned vector will have the same length as the SIMD width.

std::vector< real > gmx::test::simdReal2Vector ( SimdReal  simd)

Convert SIMD real to std::vector<real>.

The returned vector will have the same length as the SIMD width.

static SimdFloat gmx_simdcall gmx::sin ( SimdFloat  x)
inlinestatic

SIMD float sin(x).

Parameters
xThe argument to evaluate sin for
Returns
Sin(x)
Attention
Do NOT call both sin & cos if you need both results, since each of them will then call sincos and waste a factor 2 in performance.
static SimdDouble gmx_simdcall gmx::sin ( SimdDouble  x)
inlinestatic

SIMD double sin(x).

Parameters
xThe argument to evaluate sin for
Returns
Sin(x)
Attention
Do NOT call both sin & cos if you need both results, since each of them will then call sincos and waste a factor 2 in performance.
static void gmx_simdcall gmx::sincos ( SimdFloat  x,
SimdFloat *  sinval,
SimdFloat *  cosval 
)
inlinestatic

SIMD float sin & cos.

Parameters
xThe argument to evaluate sin/cos for
[out]sinvalSin(x)
[out]cosvalCos(x)

This version achieves close to machine precision, but for very large magnitudes of the argument we inherently begin to lose accuracy due to the argument reduction, despite using extended precision arithmetics internally.

static void gmx_simdcall gmx::sincos ( SimdDouble  x,
SimdDouble *  sinval,
SimdDouble *  cosval 
)
inlinestatic

SIMD double sin & cos.

Parameters
xThe argument to evaluate sin/cos for
[out]sinvalSin(x)
[out]cosvalCos(x)

This version achieves close to machine precision, but for very large magnitudes of the argument we inherently begin to lose accuracy due to the argument reduction, despite using extended precision arithmetics internally.

static void gmx_simdcall gmx::sinCosSingleAccuracy ( SimdDouble  x,
SimdDouble *  sinval,
SimdDouble *  cosval 
)
inlinestatic

SIMD sin & cos. Double precision SIMD data, single accuracy.

Parameters
xThe argument to evaluate sin/cos for
[out]sinvalSin(x)
[out]cosvalCos(x)
static void gmx_simdcall gmx::sinCosSingleAccuracy ( SimdFloat  x,
SimdFloat *  sinval,
SimdFloat *  cosval 
)
inlinestatic

SIMD float sin & cos, only targeting single accuracy.

Parameters
xThe argument to evaluate sin/cos for
[out]sinvalSin(x)
[out]cosvalCos(x)
static SimdDouble gmx_simdcall gmx::sinSingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD sin(x). Double precision SIMD data, single accuracy.

Parameters
xThe argument to evaluate sin for
Returns
Sin(x)
Attention
Do NOT call both sin & cos if you need both results, since each of them will then call sincos and waste a factor 2 in performance.
static SimdFloat gmx_simdcall gmx::sinSingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float sin(x), only targeting single accuracy.

Parameters
xThe argument to evaluate sin for
Returns
Sin(x)
Attention
Do NOT call both sin & cos if you need both results, since each of them will then call sincos and waste a factor 2 in performance.
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::sqrt ( SimdFloat  x)
inlinestatic

Calculate sqrt(x) for SIMD floats.

Template Parameters
optBy default, this function checks if the input value is 0.0 and masks this to return the correct result. If you are certain your argument will never be zero, and you know you need to save every single cycle you can, you can alternatively call the function as sqrt<MathOptimization::Unsafe>(x).
Parameters
xArgument that must be in range 0 <=x <= GMX_FLOAT_MAX, since the lookup step often has to be implemented in single precision. Arguments smaller than GMX_FLOAT_MIN will always lead to a zero result, even in double precision. If you are using the unsafe math optimization parameter, the argument must be in the range GMX_FLOAT_MIN <= x <= GMX_FLOAT_MAX.
Returns
sqrt(x). The result is undefined if the input value does not fall in the allowed range specified for the argument.
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::sqrt ( SimdDouble  x)
inlinestatic

Calculate sqrt(x) for SIMD doubles.

Template Parameters
optBy default, this function checks if the input value is 0.0 and masks this to return the correct result. If you are certain your argument will never be zero, and you know you need to save every single cycle you can, you can alternatively call the function as sqrt<MathOptimization::Unsafe>(x).
Parameters
xArgument that must be in range 0 <=x <= GMX_FLOAT_MAX, since the lookup step often has to be implemented in single precision. Arguments smaller than GMX_FLOAT_MIN will always lead to a zero result, even in double precision. If you are using the unsafe math optimization parameter, the argument must be in the range GMX_FLOAT_MIN <= x <= GMX_FLOAT_MAX.
Returns
sqrt(x). The result is undefined if the input value does not fall in the allowed range specified for the argument.
template<MathOptimization opt = MathOptimization::Safe>
static SimdDouble gmx_simdcall gmx::sqrtSingleAccuracy ( SimdDouble  x)
inlinestatic

Calculate sqrt(x) (correct for 0.0) for SIMD double, with single accuracy.

Template Parameters
optBy default, this function checks if the input value is 0.0 and masks this to return the correct result. If you are certain your argument will never be zero, and you know you need to save every single cycle you can, you can alternatively call the function as sqrt<MathOptimization::Unsafe>(x).
Parameters
xArgument that must be in range 0 <=x <= GMX_FLOAT_MAX, since the lookup step often has to be implemented in single precision. Arguments smaller than GMX_FLOAT_MIN will always lead to a zero result, even in double precision. If you are using the unsafe math optimization parameter, the argument must be in the range GMX_FLOAT_MIN <= x <= GMX_FLOAT_MAX.
Returns
sqrt(x). The result is undefined if the input value does not fall in the allowed range specified for the argument.
template<MathOptimization opt = MathOptimization::Safe>
static SimdFloat gmx_simdcall gmx::sqrtSingleAccuracy ( SimdFloat  x)
inlinestatic

Calculate sqrt(x) for SIMD float, always targeting single accuracy.

Template Parameters
optBy default, this function checks if the input value is 0.0 and masks this to return the correct result. If you are certain your argument will never be zero, and you know you need to save every single cycle you can, you can alternatively call the function as sqrt<MathOptimization::Unsafe>(x).
Parameters
xArgument that must be in range 0 <=x <= GMX_FLOAT_MAX, since the lookup step often has to be implemented in single precision. Arguments smaller than GMX_FLOAT_MIN will always lead to a zero result, even in double precision. If you are using the unsafe math optimization parameter, the argument must be in the range GMX_FLOAT_MIN <= x <= GMX_FLOAT_MAX.
Returns
sqrt(x). The result is undefined if the input value does not fall in the allowed range specified for the argument.
static void gmx_simdcall gmx::store4 ( double *  m,
Simd4Double  a 
)
inlinestatic

Store the contents of SIMD4 double to aligned memory m.

Parameters
[out]mPointer to memory, aligned to 4 elements.
aSIMD4 variable to store
static void gmx_simdcall gmx::store4 ( float *  m,
Simd4Float  a 
)
inlinestatic

Store the contents of SIMD4 float to aligned memory m.

Parameters
[out]mPointer to memory, aligned to 4 elements.
aSIMD4 variable to store
static void gmx_simdcall gmx::store4U ( double *  m,
Simd4Double  a 
)
inlinestatic

Store SIMD4 double to unaligned memory.

Available if GMX_SIMD_HAVE_STOREU is 1.

Parameters
[out]mPointer to memory, no alignment requirement.
aSIMD4 variable to store.
static void gmx_simdcall gmx::store4U ( float *  m,
Simd4Float  a 
)
inlinestatic

Store SIMD4 float to unaligned memory.

Available if GMX_SIMD_HAVE_STOREU is 1.

Parameters
[out]mPointer to memory, no alignment requirement.
aSIMD4 variable to store.
static SimdFloat gmx_simdcall gmx::tan ( SimdFloat  x)
inlinestatic

SIMD float tan(x).

Parameters
xThe argument to evaluate tan for
Returns
Tan(x)
static SimdDouble gmx_simdcall gmx::tan ( SimdDouble  x)
inlinestatic

SIMD double tan(x).

Parameters
xThe argument to evaluate tan for
Returns
Tan(x)
static SimdDouble gmx_simdcall gmx::tanSingleAccuracy ( SimdDouble  x)
inlinestatic

SIMD tan(x). Double precision SIMD data, single accuracy.

Parameters
xThe argument to evaluate tan for
Returns
Tan(x)
static SimdFloat gmx_simdcall gmx::tanSingleAccuracy ( SimdFloat  x)
inlinestatic

SIMD float tan(x), only targeting single accuracy.

Parameters
xThe argument to evaluate tan for
Returns
Tan(x)
static void gmx_simdcall gmx::transpose ( Simd4Float *  v0,
Simd4Float *  v1,
Simd4Float *  v2,
Simd4Float *  v3 
)
inlinestatic

SIMD4 float transpose.

Parameters
[in,out]v0Row 0 on input, column 0 on output
[in,out]v1Row 1 on input, column 1 on output
[in,out]v2Row 2 on input, column 2 on output
[in,out]v3Row 3 on input, column 3 on output
static void gmx_simdcall gmx::transpose ( Simd4Double *  v0,
Simd4Double *  v1,
Simd4Double *  v2,
Simd4Double *  v3 
)
inlinestatic

SIMD4 double transpose.

Parameters
[in,out]v0Row 0 on input, column 0 on output
[in,out]v1Row 1 on input, column 1 on output
[in,out]v2Row 2 on input, column 2 on output
[in,out]v3Row 3 on input, column 3 on output
template<int align>
static void gmx_simdcall gmx::transposeScatterDecrU ( double *  base,
const std::int32_t  offset[],
SimdDouble  v0,
SimdDouble  v1,
SimdDouble  v2 
)
inlinestatic

Transpose and subtract 3 SIMD doubles to 3 consecutive addresses at GMX_SIMD_DOUBLE_WIDTH offsets.

Template Parameters
alignAlignment of the memory to which we write, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 3 for this routine) the output data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are decremented.
Parameters
[out]basePointer to start of memory.
offsetAligned array with offsets to the start of each triplet.
v01st component, subtracted from base[align*offset[i]]
v12nd component, subtracted from base[align*offset[i]+1]
v23rd component, subtracted from base[align*offset[i]+2]

This function can work with both aligned (better performance) and unaligned memory. When the align parameter is not a power-of-two (align==3 would be normal for packed atomic coordinates) the memory obviously cannot be aligned, and we account for this. However, in the case where align is a power-of-two, we assume the base pointer also has the same alignment, which will enable many platforms to use faster aligned memory load/store operations. An easy way to think of this is that each triplet of data in memory must be aligned to the align parameter you specify when it's a power-of-two.

The offset memory must always be aligned to GMX_SIMD_FINT32_WIDTH, since this enables us to use SIMD loads and gather operations on platforms that support it.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This routine uses a normal array for the offsets, since we typically load the data from memory. On the architectures we have tested this is faster even when a SIMD integer datatype is present.
To improve performance, this function might use full-SIMD-width unaligned load/store, and subtract 0.0 from the extra elements. This means you need to ensure the memory is padded at the end, so we always can load GMX_SIMD_REAL_WIDTH elements starting at the last offset. If you use the Gromacs aligned memory allocation routines this will always be the case.
template<int align>
static void gmx_simdcall gmx::transposeScatterDecrU ( float *  base,
const std::int32_t  offset[],
SimdFloat  v0,
SimdFloat  v1,
SimdFloat  v2 
)
inlinestatic

Transpose and subtract 3 SIMD floats to 3 consecutive addresses at GMX_SIMD_FLOAT_WIDTH offsets.

Template Parameters
alignAlignment of the memory to which we write, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 3 for this routine) the output data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are decremented.
Parameters
[out]basePointer to start of memory.
offsetAligned array with offsets to the start of each triplet.
v01st component, subtracted from base[align*offset[i]]
v12nd component, subtracted from base[align*offset[i]+1]
v23rd component, subtracted from base[align*offset[i]+2]

This function can work with both aligned (better performance) and unaligned memory. When the align parameter is not a power-of-two (align==3 would be normal for packed atomic coordinates) the memory obviously cannot be aligned, and we account for this. However, in the case where align is a power-of-two, we assume the base pointer also has the same alignment, which will enable many platforms to use faster aligned memory load/store operations. An easy way to think of this is that each triplet of data in memory must be aligned to the align parameter you specify when it's a power-of-two.

The offset memory must always be aligned to GMX_SIMD_FINT32_WIDTH, since this enables us to use SIMD loads and gather operations on platforms that support it.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This routine uses a normal array for the offsets, since we typically load the data from memory. On the architectures we have tested this is faster even when a SIMD integer datatype is present.
To improve performance, this function might use full-SIMD-width unaligned load/store, and subtract 0.0 from the extra elements. This means you need to ensure the memory is padded at the end, so we always can load GMX_SIMD_REAL_WIDTH elements starting at the last offset. If you use the Gromacs aligned memory allocation routines this will always be the case.
template<int align>
static void gmx_simdcall gmx::transposeScatterIncrU ( double *  base,
const std::int32_t  offset[],
SimdDouble  v0,
SimdDouble  v1,
SimdDouble  v2 
)
inlinestatic

Transpose and add 3 SIMD doubles to 3 consecutive addresses at GMX_SIMD_DOUBLE_WIDTH offsets.

Template Parameters
alignAlignment of the memory to which we write, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 3 for this routine) the output data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are incremented.
Parameters
[out]basePointer to the start of the memory area
offsetAligned array with offsets to the start of each triplet.
v01st component of triplets, added to base[align*offset[i]].
v12nd component of triplets, added to base[align*offset[i] + 1].
v23rd component of triplets, added to base[align*offset[i] + 2].

This function can work with both aligned (better performance) and unaligned memory. When the align parameter is not a power-of-two (align==3 would be normal for packed atomic coordinates) the memory obviously cannot be aligned, and we account for this. However, in the case where align is a power-of-two, we assume the base pointer also has the same alignment, which will enable many platforms to use faster aligned memory load/store operations. An easy way to think of this is that each triplet of data in memory must be aligned to the align parameter you specify when it's a power-of-two.

The offset memory must always be aligned to GMX_SIMD_FINT32_WIDTH, since this enables us to use SIMD loads and gather operations on platforms that support it.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This routine uses a normal array for the offsets, since we typically load the data from memory. On the architectures we have tested this is faster even when a SIMD integer datatype is present.
To improve performance, this function might use full-SIMD-width unaligned load/store, and add 0.0 to the extra elements. This means you need to ensure the memory is padded at the end, so we always can load GMX_SIMD_REAL_WIDTH elements starting at the last offset. If you use the Gromacs aligned memory allocation routines this will always be the case.
template<int align>
static void gmx_simdcall gmx::transposeScatterIncrU ( float *  base,
const std::int32_t  offset[],
SimdFloat  v0,
SimdFloat  v1,
SimdFloat  v2 
)
inlinestatic

Transpose and add 3 SIMD floats to 3 consecutive addresses at GMX_SIMD_FLOAT_WIDTH offsets.

Template Parameters
alignAlignment of the memory to which we write, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 3 for this routine) the output data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are incremented.
Parameters
[out]basePointer to the start of the memory area
offsetAligned array with offsets to the start of each triplet.
v01st component of triplets, added to base[align*offset[i]].
v12nd component of triplets, added to base[align*offset[i] + 1].
v23rd component of triplets, added to base[align*offset[i] + 2].

This function can work with both aligned (better performance) and unaligned memory. When the align parameter is not a power-of-two (align==3 would be normal for packed atomic coordinates) the memory obviously cannot be aligned, and we account for this. However, in the case where align is a power-of-two, we assume the base pointer also has the same alignment, which will enable many platforms to use faster aligned memory load/store operations. An easy way to think of this is that each triplet of data in memory must be aligned to the align parameter you specify when it's a power-of-two.

The offset memory must always be aligned to GMX_SIMD_FINT32_WIDTH, since this enables us to use SIMD loads and gather operations on platforms that support it.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This routine uses a normal array for the offsets, since we typically load the data from memory. On the architectures we have tested this is faster even when a SIMD integer datatype is present.
To improve performance, this function might use full-SIMD-width unaligned load/store, and add 0.0 to the extra elements. This means you need to ensure the memory is padded at the end, so we always can load GMX_SIMD_REAL_WIDTH elements starting at the last offset. If you use the Gromacs aligned memory allocation routines this will always be the case.
template<int align>
static void gmx_simdcall gmx::transposeScatterStoreU ( double *  base,
const std::int32_t  offset[],
SimdDouble  v0,
SimdDouble  v1,
SimdDouble  v2 
)
inlinestatic

Transpose and store 3 SIMD doubles to 3 consecutive addresses at GMX_SIMD_DOUBLE_WIDTH offsets.

Template Parameters
alignAlignment of the memory to which we write, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 3 for this routine) the output data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are written.
Parameters
[out]basePointer to the start of the memory area
offsetAligned array with offsets to the start of each triplet.
v01st component of triplets, written to base[align*offset[i]].
v12nd component of triplets, written to base[align*offset[i] + 1].
v23rd component of triplets, written to base[align*offset[i] + 2].

This function can work with both aligned (better performance) and unaligned memory. When the align parameter is not a power-of-two (align==3 would be normal for packed atomic coordinates) the memory obviously cannot be aligned, and we account for this. However, in the case where align is a power-of-two, we assume the base pointer also has the same alignment, which will enable many platforms to use faster aligned memory store operations. An easy way to think of this is that each triplet of data in memory must be aligned to the align parameter you specify when it's a power-of-two.

The offset memory must always be aligned to GMX_SIMD_FINT32_WIDTH, since this enables us to use SIMD loads and gather operations on platforms that support it.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This routine uses a normal array for the offsets, since we typically load the data from memory. On the architectures we have tested this is faster even when a SIMD integer datatype is present.
template<int align>
static void gmx_simdcall gmx::transposeScatterStoreU ( float *  base,
const std::int32_t  offset[],
SimdFloat  v0,
SimdFloat  v1,
SimdFloat  v2 
)
inlinestatic

Transpose and store 3 SIMD floats to 3 consecutive addresses at GMX_SIMD_FLOAT_WIDTH offsets.

Template Parameters
alignAlignment of the memory to which we write, i.e. distance (measured in elements, not bytes) between index points. When this is identical to the number of SIMD variables (i.e., 3 for this routine) the output data is packed without padding in memory. See the SIMD parameters for exactly what memory positions are written.
Parameters
[out]basePointer to the start of the memory area
offsetAligned array with offsets to the start of each triplet.
v01st component of triplets, written to base[align*offset[i]].
v12nd component of triplets, written to base[align*offset[i] + 1].
v23rd component of triplets, written to base[align*offset[i] + 2].

This function can work with both aligned (better performance) and unaligned memory. When the align parameter is not a power-of-two (align==3 would be normal for packed atomic coordinates) the memory obviously cannot be aligned, and we account for this. However, in the case where align is a power-of-two, we assume the base pointer also has the same alignment, which will enable many platforms to use faster aligned memory store operations. An easy way to think of this is that each triplet of data in memory must be aligned to the align parameter you specify when it's a power-of-two.

The offset memory must always be aligned to GMX_SIMD_FINT32_WIDTH, since this enables us to use SIMD loads and gather operations on platforms that support it.

Note
You should NOT scale offsets before calling this routine; it is done internally by using the alignment template parameter instead.
This routine uses a normal array for the offsets, since we typically load the data from memory. On the architectures we have tested this is faster even when a SIMD integer datatype is present.
static Simd4Float gmx_simdcall gmx::trunc ( Simd4Float  a)
inlinestatic

Truncate SIMD4, i.e. round towards zero - common hardware instruction.

Parameters
aAny floating-point value
Returns
Integer rounded towards zero, represented in floating-point format.
Note
This is truncation towards zero, not floor(). The reason for this is that truncation is virtually always present as a dedicated hardware instruction, but floor() frequently isn't.
static Simd4Double gmx_simdcall gmx::trunc ( Simd4Double  a)
inlinestatic

Truncate SIMD4, i.e. round towards zero - common hardware instruction.

Parameters
aAny floating-point value
Returns
Integer rounded towards zero, represented in floating-point format.
Note
This is truncation towards zero, not floor(). The reason for this is that truncation is virtually always present as a dedicated hardware instruction, but floor() frequently isn't.
Simd4Real gmx::test::vector2Simd4Real ( const std::vector< real > &  v)

Return floating-point SIMD4 value from std::vector<real>.

If the vector is longer than SIMD4 width, only the first elements will be used. If it is shorter, the contents will be repeated to fill the SIMD4 register.

SimdInt32 gmx::test::vector2SimdInt ( const std::vector< std::int32_t > &  v)

Return 32-bit integer SIMD value from std::vector<int>.

If the vector is longer than SIMD width, only the first elements will be used. If it is shorter, the contents will be repeated to fill the SIMD register.

SimdReal gmx::test::vector2SimdReal ( const std::vector< real > &  v)

Return floating-point SIMD value from std::vector<real>.

If the vector is longer than SIMD width, only the first elements will be used. If it is shorter, the contents will be repeated to fill the SIMD register.

Variable Documentation

const int gmx::c_simdBestPairAlignmentDouble = 2
static

Best alignment to use for aligned pairs of double data.

The routines to load and transpose data will work with a wide range of alignments, but some might be faster than others, depending on the load instructions available in the hardware. This specifies the best alignment for each implementation when working with pairs of data.

To allow each architecture to use the most optimal form, we use a constant that code outside the SIMD module should use to store things properly. It must be at least 2. For example, a value of 2 means the two parameters A & B are stored as [A0 B0 A1 B1] while align-4 means [A0 B0 - - A1 B1 - -].

This alignment depends on the efficiency of partial-register load/store operations, and will depend on the architecture.

const int gmx::c_simdBestPairAlignmentFloat = 2
static

Best alignment to use for aligned pairs of float data.

The routines to load and transpose data will work with a wide range of alignments, but some might be faster than others, depending on the load instructions available in the hardware. This specifies the best alignment for each implementation when working with pairs of data.

To allow each architecture to use the most optimal form, we use a constant that code outside the SIMD module should use to store things properly. It must be at least 2. For example, a value of 2 means the two parameters A & B are stored as [A0 B0 A1 B1] while align-4 means [A0 B0 - - A1 B1 - -].

This alignment depends on the efficiency of partial-register load/store operations, and will depend on the architecture.

const Simd4Real gmx::test::rSimd4_m3p75 = setSimd4RealFrom1R(-3.75)

Negative value that rounds down.

const SimdReal gmx::test::rSimd_Exp
Initial value:
= setSimdRealFrom3R(1.4055235171027452623914516e+18,
5.3057102734253445623914516e-13,
-2.1057102745623934534514516e+16)
SimdReal setSimdRealFrom3R(real r0, real r1, real r2)
Set SIMD register contents from three real values.
Definition: simd.cpp:181

Three large floating-point values whose exponents are >32.

const SimdReal gmx::test::rSimd_m3p75 = setSimdRealFrom1R(-3.75)

Negative value that rounds down.

int gmx::test::SimdBaseTest::s_nPoints = 10000
static

Number of test points to use, settable on command line.

Note
While this has to be a static non-const variable for the command-line option to work, you should never change it manually in any of the tests, because the static storage class will make the value apply to all subsequent tests unless you remember to reset it.