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* Big change in Block and Map:

Browse Source 
- added a MapBase base xpr on top of which Map and the specialization
    of Block are implemented
  - MapBase forces both aligned loads (and aligned stores, see below) in expressions
    such as "x.block(...) += other_expr"
* Significant vectorization improvement:
 - added a AlignedBit flag meaning the first coeff/packet is aligned,
   this allows to not generate extra code to deal with the first unaligned part
 - removed all unaligned stores when no unrolling
 - removed unaligned loads in Sum when the input as the DirectAccessBit flag
* Some code simplification in CacheFriendly product
* Some minor documentation improvements
This commit is contained in:
Gael Guennebaud
2008-08-09 18:41:24 +00:00
parent becbeda50a
commit 4fa40367e9
17 changed files with 397 additions and 296 deletions
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36
Eigen/src/Core/Sum.h
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@@ -33,17 +33,22 @@
template<typename Derived>
struct ei_sum_traits
{
private:
enum {
PacketSize = ei_packet_traits<typename Derived::Scalar>::size
};
public:
enum {
Vectorization = (int(Derived::Flags)&ActualPacketAccessBit)
&& (int(Derived::Flags)&LinearAccessBit)
&& (int(Derived::SizeAtCompileTime)>2*PacketSize)
? LinearVectorization
: NoVectorization
};
private:
enum {
PacketSize = ei_packet_traits<typename Derived::Scalar>::size,
Cost = Derived::SizeAtCompileTime * Derived::CoeffReadCost
+ (Derived::SizeAtCompileTime-1) * NumTraits<typename Derived::Scalar>::AddCost,
UnrollingLimit = EIGEN_UNROLLING_LIMIT * (int(Vectorization) == int(NoVectorization) ? 1 : int(PacketSize))
@@ -131,7 +136,8 @@ struct ei_sum_vec_unroller<Derived, Index, Stop, true>
: Index % Derived::RowsAtCompileTime,
col = int(Derived::Flags)&RowMajorBit
? Index % int(Derived::ColsAtCompileTime)
: Index / Derived::RowsAtCompileTime
: Index / Derived::RowsAtCompileTime,
alignment = (Derived::Flags & AlignedBit) ? Aligned : Unaligned
};
typedef typename Derived::Scalar Scalar;
@@ -139,7 +145,7 @@ struct ei_sum_vec_unroller<Derived, Index, Stop, true>
inline static PacketScalar run(const Derived &mat)
{
return mat.template packet<Aligned>(row, col);
return mat.template packet<alignment>(row, col);
}
};
@@ -185,14 +191,21 @@ struct ei_sum_impl<Derived, LinearVectorization, NoUnrolling>
{
const int size = mat.size();
const int packetSize = ei_packet_traits<Scalar>::size;
const int alignedSize = (size/packetSize)*packetSize;
const int alignedStart = (Derived::Flags & AlignedBit)
|| !(Derived::Flags & DirectAccessBit)
? 0
: ei_alignmentOffset(&mat.const_cast_derived().coeffRef(0), size);
const int alignment = (Derived::Flags & DirectAccessBit) || (Derived::Flags & AlignedBit)
? Aligned : Unaligned;
const int alignedSize = ((size-alignedStart)/packetSize)*packetSize;
const int alignedEnd = alignedStart + alignedSize;
Scalar res;
if(size >= packetSize)
if(Derived::SizeAtCompileTime>=2*packetSize && alignedSize >= 2*packetSize)
{
PacketScalar packet_res = mat.template packet<Aligned>(0, 0);
for(int index = packetSize; index < alignedSize; index += packetSize)
packet_res = ei_padd(packet_res, mat.template packet<Aligned>(index));
PacketScalar packet_res = mat.template packet<alignment>(alignedStart, alignedStart);
for(int index = alignedStart + packetSize; index < alignedEnd; index += packetSize)
packet_res = ei_padd(packet_res, mat.template packet<alignment>(index));
res = ei_predux(packet_res);
}
@@ -202,10 +215,11 @@ struct ei_sum_impl<Derived, LinearVectorization, NoUnrolling>
res = Scalar(0);
}
for(int index = alignedSize; index < size; index++)
{
for(int index = alignedEnd; index < size; index++)
res += mat.coeff(index);
for(int index = alignedEnd; index < size; index++)
res += mat.coeff(index);
}
return res;
}