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Diffstat (limited to 'eigen/Eigen/src/SparseLU/SparseLU_gemm_kernel.h')
-rw-r--r-- | eigen/Eigen/src/SparseLU/SparseLU_gemm_kernel.h | 279 |
1 files changed, 279 insertions, 0 deletions
diff --git a/eigen/Eigen/src/SparseLU/SparseLU_gemm_kernel.h b/eigen/Eigen/src/SparseLU/SparseLU_gemm_kernel.h new file mode 100644 index 0000000..9e4e3e7 --- /dev/null +++ b/eigen/Eigen/src/SparseLU/SparseLU_gemm_kernel.h @@ -0,0 +1,279 @@ +// This file is part of Eigen, a lightweight C++ template library +// for linear algebra. +// +// Copyright (C) 2012 Gael Guennebaud <gael.guennebaud@inria.fr> +// +// This Source Code Form is subject to the terms of the Mozilla +// Public License v. 2.0. If a copy of the MPL was not distributed +// with this file, You can obtain one at http://mozilla.org/MPL/2.0/. + +#ifndef EIGEN_SPARSELU_GEMM_KERNEL_H +#define EIGEN_SPARSELU_GEMM_KERNEL_H + +namespace Eigen { + +namespace internal { + + +/** \internal + * A general matrix-matrix product kernel optimized for the SparseLU factorization. + * - A, B, and C must be column major + * - lda and ldc must be multiples of the respective packet size + * - C must have the same alignment as A + */ +template<typename Scalar,typename Index> +EIGEN_DONT_INLINE +void sparselu_gemm(Index m, Index n, Index d, const Scalar* A, Index lda, const Scalar* B, Index ldb, Scalar* C, Index ldc) +{ + using namespace Eigen::internal; + + typedef typename packet_traits<Scalar>::type Packet; + enum { + NumberOfRegisters = EIGEN_ARCH_DEFAULT_NUMBER_OF_REGISTERS, + PacketSize = packet_traits<Scalar>::size, + PM = 8, // peeling in M + RN = 2, // register blocking + RK = NumberOfRegisters>=16 ? 4 : 2, // register blocking + BM = 4096/sizeof(Scalar), // number of rows of A-C per chunk + SM = PM*PacketSize // step along M + }; + Index d_end = (d/RK)*RK; // number of columns of A (rows of B) suitable for full register blocking + Index n_end = (n/RN)*RN; // number of columns of B-C suitable for processing RN columns at once + Index i0 = internal::first_aligned(A,m); + + eigen_internal_assert(((lda%PacketSize)==0) && ((ldc%PacketSize)==0) && (i0==internal::first_aligned(C,m))); + + // handle the non aligned rows of A and C without any optimization: + for(Index i=0; i<i0; ++i) + { + for(Index j=0; j<n; ++j) + { + Scalar c = C[i+j*ldc]; + for(Index k=0; k<d; ++k) + c += B[k+j*ldb] * A[i+k*lda]; + C[i+j*ldc] = c; + } + } + // process the remaining rows per chunk of BM rows + for(Index ib=i0; ib<m; ib+=BM) + { + Index actual_b = std::min<Index>(BM, m-ib); // actual number of rows + Index actual_b_end1 = (actual_b/SM)*SM; // actual number of rows suitable for peeling + Index actual_b_end2 = (actual_b/PacketSize)*PacketSize; // actual number of rows suitable for vectorization + + // Let's process two columns of B-C at once + for(Index j=0; j<n_end; j+=RN) + { + const Scalar* Bc0 = B+(j+0)*ldb; + const Scalar* Bc1 = B+(j+1)*ldb; + + for(Index k=0; k<d_end; k+=RK) + { + + // load and expand a RN x RK block of B + Packet b00, b10, b20, b30, b01, b11, b21, b31; + b00 = pset1<Packet>(Bc0[0]); + b10 = pset1<Packet>(Bc0[1]); + if(RK==4) b20 = pset1<Packet>(Bc0[2]); + if(RK==4) b30 = pset1<Packet>(Bc0[3]); + b01 = pset1<Packet>(Bc1[0]); + b11 = pset1<Packet>(Bc1[1]); + if(RK==4) b21 = pset1<Packet>(Bc1[2]); + if(RK==4) b31 = pset1<Packet>(Bc1[3]); + + Packet a0, a1, a2, a3, c0, c1, t0, t1; + + const Scalar* A0 = A+ib+(k+0)*lda; + const Scalar* A1 = A+ib+(k+1)*lda; + const Scalar* A2 = A+ib+(k+2)*lda; + const Scalar* A3 = A+ib+(k+3)*lda; + + Scalar* C0 = C+ib+(j+0)*ldc; + Scalar* C1 = C+ib+(j+1)*ldc; + + a0 = pload<Packet>(A0); + a1 = pload<Packet>(A1); + if(RK==4) + { + a2 = pload<Packet>(A2); + a3 = pload<Packet>(A3); + } + else + { + // workaround "may be used uninitialized in this function" warning + a2 = a3 = a0; + } + +#define KMADD(c, a, b, tmp) {tmp = b; tmp = pmul(a,tmp); c = padd(c,tmp);} +#define WORK(I) \ + c0 = pload<Packet>(C0+i+(I)*PacketSize); \ + c1 = pload<Packet>(C1+i+(I)*PacketSize); \ + KMADD(c0, a0, b00, t0) \ + KMADD(c1, a0, b01, t1) \ + a0 = pload<Packet>(A0+i+(I+1)*PacketSize); \ + KMADD(c0, a1, b10, t0) \ + KMADD(c1, a1, b11, t1) \ + a1 = pload<Packet>(A1+i+(I+1)*PacketSize); \ + if(RK==4) KMADD(c0, a2, b20, t0) \ + if(RK==4) KMADD(c1, a2, b21, t1) \ + if(RK==4) a2 = pload<Packet>(A2+i+(I+1)*PacketSize); \ + if(RK==4) KMADD(c0, a3, b30, t0) \ + if(RK==4) KMADD(c1, a3, b31, t1) \ + if(RK==4) a3 = pload<Packet>(A3+i+(I+1)*PacketSize); \ + pstore(C0+i+(I)*PacketSize, c0); \ + pstore(C1+i+(I)*PacketSize, c1) + + // process rows of A' - C' with aggressive vectorization and peeling + for(Index i=0; i<actual_b_end1; i+=PacketSize*8) + { + EIGEN_ASM_COMMENT("SPARSELU_GEMML_KERNEL1"); + prefetch((A0+i+(5)*PacketSize)); + prefetch((A1+i+(5)*PacketSize)); + if(RK==4) prefetch((A2+i+(5)*PacketSize)); + if(RK==4) prefetch((A3+i+(5)*PacketSize)); + WORK(0); + WORK(1); + WORK(2); + WORK(3); + WORK(4); + WORK(5); + WORK(6); + WORK(7); + } + // process the remaining rows with vectorization only + for(Index i=actual_b_end1; i<actual_b_end2; i+=PacketSize) + { + WORK(0); + } +#undef WORK + // process the remaining rows without vectorization + for(Index i=actual_b_end2; i<actual_b; ++i) + { + if(RK==4) + { + C0[i] += A0[i]*Bc0[0]+A1[i]*Bc0[1]+A2[i]*Bc0[2]+A3[i]*Bc0[3]; + C1[i] += A0[i]*Bc1[0]+A1[i]*Bc1[1]+A2[i]*Bc1[2]+A3[i]*Bc1[3]; + } + else + { + C0[i] += A0[i]*Bc0[0]+A1[i]*Bc0[1]; + C1[i] += A0[i]*Bc1[0]+A1[i]*Bc1[1]; + } + } + + Bc0 += RK; + Bc1 += RK; + } // peeled loop on k + } // peeled loop on the columns j + // process the last column (we now perform a matrux-vector product) + if((n-n_end)>0) + { + const Scalar* Bc0 = B+(n-1)*ldb; + + for(Index k=0; k<d_end; k+=RK) + { + + // load and expand a 1 x RK block of B + Packet b00, b10, b20, b30; + b00 = pset1<Packet>(Bc0[0]); + b10 = pset1<Packet>(Bc0[1]); + if(RK==4) b20 = pset1<Packet>(Bc0[2]); + if(RK==4) b30 = pset1<Packet>(Bc0[3]); + + Packet a0, a1, a2, a3, c0, t0/*, t1*/; + + const Scalar* A0 = A+ib+(k+0)*lda; + const Scalar* A1 = A+ib+(k+1)*lda; + const Scalar* A2 = A+ib+(k+2)*lda; + const Scalar* A3 = A+ib+(k+3)*lda; + + Scalar* C0 = C+ib+(n_end)*ldc; + + a0 = pload<Packet>(A0); + a1 = pload<Packet>(A1); + if(RK==4) + { + a2 = pload<Packet>(A2); + a3 = pload<Packet>(A3); + } + else + { + // workaround "may be used uninitialized in this function" warning + a2 = a3 = a0; + } + +#define WORK(I) \ + c0 = pload<Packet>(C0+i+(I)*PacketSize); \ + KMADD(c0, a0, b00, t0) \ + a0 = pload<Packet>(A0+i+(I+1)*PacketSize); \ + KMADD(c0, a1, b10, t0) \ + a1 = pload<Packet>(A1+i+(I+1)*PacketSize); \ + if(RK==4) KMADD(c0, a2, b20, t0) \ + if(RK==4) a2 = pload<Packet>(A2+i+(I+1)*PacketSize); \ + if(RK==4) KMADD(c0, a3, b30, t0) \ + if(RK==4) a3 = pload<Packet>(A3+i+(I+1)*PacketSize); \ + pstore(C0+i+(I)*PacketSize, c0); + + // agressive vectorization and peeling + for(Index i=0; i<actual_b_end1; i+=PacketSize*8) + { + EIGEN_ASM_COMMENT("SPARSELU_GEMML_KERNEL2"); + WORK(0); + WORK(1); + WORK(2); + WORK(3); + WORK(4); + WORK(5); + WORK(6); + WORK(7); + } + // vectorization only + for(Index i=actual_b_end1; i<actual_b_end2; i+=PacketSize) + { + WORK(0); + } + // remaining scalars + for(Index i=actual_b_end2; i<actual_b; ++i) + { + if(RK==4) + C0[i] += A0[i]*Bc0[0]+A1[i]*Bc0[1]+A2[i]*Bc0[2]+A3[i]*Bc0[3]; + else + C0[i] += A0[i]*Bc0[0]+A1[i]*Bc0[1]; + } + + Bc0 += RK; +#undef WORK + } + } + + // process the last columns of A, corresponding to the last rows of B + Index rd = d-d_end; + if(rd>0) + { + for(Index j=0; j<n; ++j) + { + enum { + Alignment = PacketSize>1 ? Aligned : 0 + }; + typedef Map<Matrix<Scalar,Dynamic,1>, Alignment > MapVector; + typedef Map<const Matrix<Scalar,Dynamic,1>, Alignment > ConstMapVector; + if(rd==1) MapVector(C+j*ldc+ib,actual_b) += B[0+d_end+j*ldb] * ConstMapVector(A+(d_end+0)*lda+ib, actual_b); + + else if(rd==2) MapVector(C+j*ldc+ib,actual_b) += B[0+d_end+j*ldb] * ConstMapVector(A+(d_end+0)*lda+ib, actual_b) + + B[1+d_end+j*ldb] * ConstMapVector(A+(d_end+1)*lda+ib, actual_b); + + else MapVector(C+j*ldc+ib,actual_b) += B[0+d_end+j*ldb] * ConstMapVector(A+(d_end+0)*lda+ib, actual_b) + + B[1+d_end+j*ldb] * ConstMapVector(A+(d_end+1)*lda+ib, actual_b) + + B[2+d_end+j*ldb] * ConstMapVector(A+(d_end+2)*lda+ib, actual_b); + } + } + + } // blocking on the rows of A and C +} +#undef KMADD + +} // namespace internal + +} // namespace Eigen + +#endif // EIGEN_SPARSELU_GEMM_KERNEL_H |