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Disable SIMD vector operations for certain types
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Disable long double SIMD instructions on ICC. This is to work around a
bug that generates wrong code at least up to intel 15 (see tests/lac
/vector-vector, tests/lac/intel-15-bug, and the discussion at
dealii#598).
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@tjhei
tjhei committed Feb 28, 2015
1 parent 54453c0 commit 197f3a1
Showing 1 changed file with 176 additions and 42 deletions.
218 changes: 176 additions & 42 deletions include/deal.II/lac/vector.templates.h
View file
Expand Up @@ -48,6 +48,28 @@

DEAL_II_NAMESPACE_OPEN

/**
* Helper struct to tell us if we can use SIMD instructions for the given @p
* Number type.
*/
template <typename Number>
struct EnableOpenMPSimdFor
{
static const bool value = true;
};

#ifdef __INTEL_COMPILER
// Disable long double SIMD instructions on ICC. This is to work around a bug
// that generates wrong code at least up to intel 15 (see
// tests/lac/vector-vector, tests/lac/intel-15-bug, and the discussion at
// https://github.com/dealii/dealii/issues/598).
template <>
struct EnableOpenMPSimdFor<long double>
{
static const bool value = false;
};
#endif


namespace internal
{
Expand Down Expand Up @@ -159,9 +181,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] *= factor;
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] *= factor;
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] *= factor;
}
}
};

Expand All @@ -180,9 +210,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] += factor*v_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] += factor*v_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] += factor*v_val[i];
}
}
};

Expand All @@ -202,9 +240,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = x*val[i] + a*v_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = x*val[i] + a*v_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] = x*val[i] + a*v_val[i];
}
}
};

Expand All @@ -222,9 +268,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] -= v_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] -= v_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] -= v_val[i];
}
}
};

Expand All @@ -242,9 +296,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] += factor;
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] += factor;
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] += factor;
}
}
};

Expand All @@ -262,9 +324,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] += v_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] += v_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] += v_val[i];
}
}
};

Expand All @@ -285,9 +355,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = val[i] + a*v_val[i] + b*w_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = val[i] + a*v_val[i] + b*w_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] = val[i] + a*v_val[i] + b*w_val[i];
}
}
};

Expand All @@ -306,9 +384,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = x*val[i] + v_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = x*val[i] + v_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] = x*val[i] + v_val[i];
}
}
};

Expand All @@ -330,9 +416,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = x*val[i] + a*v_val[i] + b*w_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = x*val[i] + a*v_val[i] + b*w_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] = x*val[i] + a*v_val[i] + b*w_val[i];
}
}
};

Expand All @@ -350,9 +444,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] *= v_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] *= v_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] *= v_val[i];
}
}
};

Expand All @@ -371,9 +473,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = a*u_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = a*u_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] = a*u_val[i];
}
}
};

Expand All @@ -394,9 +504,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = a*u_val[i] + b*v_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = a*u_val[i] + b*v_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] = a*u_val[i] + b*v_val[i];
}
}
};

Expand All @@ -419,9 +537,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = a*u_val[i] + b*v_val[i] + c*w_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = a*u_val[i] + b*v_val[i] + c*w_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] = a*u_val[i] + b*v_val[i] + c*w_val[i];
}
}
};

Expand All @@ -440,9 +566,17 @@ namespace internal

void operator() (const size_type begin, const size_type end) const
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = a_val[i]/b_val[i];
if (EnableOpenMPSimdFor<Number>::value)
{
DEAL_II_OPENMP_SIMD_PRAGMA
for (size_type i=begin; i<end; ++i)
val[i] = a_val[i]/b_val[i];
}
else
{
for (size_type i=begin; i<end; ++i)
val[i] = a_val[i]/b_val[i];
}
}
};

Expand Down

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