1bcb2dfaeSJed Brown# Changes/Release Notes 2bcb2dfaeSJed Brown 3bcb2dfaeSJed BrownOn this page we provide a summary of the main API changes, new features and examples 4bcb2dfaeSJed Brownfor each release of libCEED. 5bcb2dfaeSJed Brown 6bcb2dfaeSJed Brown(main)= 7bcb2dfaeSJed Brown 8bcb2dfaeSJed Brown## Current `main` branch 9bcb2dfaeSJed Brown 10*7e7773b5SJeremy L Thompson### Interface changes 11*7e7773b5SJeremy L Thompson 12*7e7773b5SJeremy L Thompson- Update {c:func} `CeedQFunctionGetFields` and {c:func} `CeedOperatorGetFields` to include number of fields. 13*7e7773b5SJeremy L Thompson 14bcb2dfaeSJed Brown### Maintainability 15bcb2dfaeSJed Brown 16bcb2dfaeSJed Brown- Refactored preconditioner support internally to facilitate future development and improve GPU completeness/test coverage. 17bcb2dfaeSJed Brown 18bcb2dfaeSJed Brown(v0-9)= 19bcb2dfaeSJed Brown 20bcb2dfaeSJed Brown## v0.9 (Jul 6, 2021) 21bcb2dfaeSJed Brown 22bcb2dfaeSJed Brown### Interface changes 23bcb2dfaeSJed Brown 24bcb2dfaeSJed Brown- Minor modification in error handling macro to silence pedantic warnings when compiling with Clang, but no functional impact. 25bcb2dfaeSJed Brown 26bcb2dfaeSJed Brown### New features 27bcb2dfaeSJed Brown 28bcb2dfaeSJed Brown- Add {c:func}`CeedVectorAXPY` and {c:func}`CeedVectorPointwiseMult` as a convenience for stand-alone testing and internal use. 29bcb2dfaeSJed Brown- Add `CEED_QFUNCTION_HELPER` macro to properly annotate QFunction helper functions for code generation backends. 30bcb2dfaeSJed Brown- Add `CeedPragmaOptimizeOff` macro for code that is sensitive to floating point errors from fast math optimizations. 31bcb2dfaeSJed Brown- Rust support: split `libceed-sys` crate out of `libceed` and [publish both on crates.io](https://crates.io/crates/libceed). 32bcb2dfaeSJed Brown 33bcb2dfaeSJed Brown### Performance improvements 34bcb2dfaeSJed Brown 35bcb2dfaeSJed Brown### Examples 36bcb2dfaeSJed Brown 37bcb2dfaeSJed Brown- Solid mechanics mini-app updated to explore the performance impacts of various formulations in the initial and current configurations. 38bcb2dfaeSJed Brown- Fluid mechanics example adds GPU support and improves modularity. 39bcb2dfaeSJed Brown 40bcb2dfaeSJed Brown### Deprecated backends 41bcb2dfaeSJed Brown 42bcb2dfaeSJed Brown- The `/cpu/self/tmpl` and `/cpu/self/tmpl/sub` backends have been removed. These backends were intially added to test the backend inheritance mechanism, but this mechanism is now widely used and tested in multiple backends. 43bcb2dfaeSJed Brown 44bcb2dfaeSJed Brown(v0-8)= 45bcb2dfaeSJed Brown 46bcb2dfaeSJed Brown## v0.8 (Mar 31, 2021) 47bcb2dfaeSJed Brown 48bcb2dfaeSJed Brown### Interface changes 49bcb2dfaeSJed Brown 50bcb2dfaeSJed Brown- Error handling improved to include enumerated error codes for C interface return values. 51bcb2dfaeSJed Brown- Installed headers that will follow semantic versioning were moved to {code}`include/ceed` directory. These headers have been renamed from {code}`ceed-*.h` to {code}`ceed/*.h`. Placeholder headers with the old naming schema are currently provided, but these headers will be removed in the libCEED v0.9 release. 52bcb2dfaeSJed Brown 53bcb2dfaeSJed Brown### New features 54bcb2dfaeSJed Brown 55bcb2dfaeSJed Brown- Julia and Rust interfaces added, providing a nearly 1-1 correspondence with the C interface, plus some convenience features. 56bcb2dfaeSJed Brown- Static libraries can be built with `make STATIC=1` and the pkg-config file is installed accordingly. 57bcb2dfaeSJed Brown- Add {c:func}`CeedOperatorLinearAssembleSymbolic` and {c:func}`CeedOperatorLinearAssemble` to support full assembly of libCEED operators. 58bcb2dfaeSJed Brown 59bcb2dfaeSJed Brown### Performance improvements 60bcb2dfaeSJed Brown 61bcb2dfaeSJed Brown- New HIP MAGMA backends for hipMAGMA library users: `/gpu/hip/magma` and `/gpu/hip/magma/det`. 62bcb2dfaeSJed Brown- New HIP backends for improved tensor basis performance: `/gpu/hip/shared` and `/gpu/hip/gen`. 63bcb2dfaeSJed Brown 64bcb2dfaeSJed Brown### Examples 65bcb2dfaeSJed Brown 66bcb2dfaeSJed Brown- {ref}`example-petsc-elasticity` example updated with traction boundary conditions and improved Dirichlet boundary conditions. 67bcb2dfaeSJed Brown- {ref}`example-petsc-elasticity` example updated with Neo-Hookean hyperelasticity in current configuration as well as improved Neo-Hookean hyperelasticity exploring storage vs computation tradeoffs. 68bcb2dfaeSJed Brown- {ref}`example-petsc-navier-stokes` example updated with isentropic traveling vortex test case, an analytical solution to the Euler equations that is useful for testing boundary conditions, discretization stability, and order of accuracy. 69bcb2dfaeSJed Brown- {ref}`example-petsc-navier-stokes` example updated with support for performing convergence study and plotting order of convergence by polynomial degree. 70bcb2dfaeSJed Brown 71bcb2dfaeSJed Brown(v0-7)= 72bcb2dfaeSJed Brown 73bcb2dfaeSJed Brown## v0.7 (Sep 29, 2020) 74bcb2dfaeSJed Brown 75bcb2dfaeSJed Brown### Interface changes 76bcb2dfaeSJed Brown 77bcb2dfaeSJed Brown- Replace limited {code}`CeedInterlaceMode` with more flexible component stride {code}`compstride` in {code}`CeedElemRestriction` constructors. 78bcb2dfaeSJed Brown As a result, the {code}`indices` parameter has been replaced with {code}`offsets` and the {code}`nnodes` parameter has been replaced with {code}`lsize`. 79bcb2dfaeSJed Brown These changes improve support for mixed finite element methods. 80bcb2dfaeSJed Brown- Replace various uses of {code}`Ceed*Get*Status` with {code}`Ceed*Is*` in the backend API to match common nomenclature. 81bcb2dfaeSJed Brown- Replace {code}`CeedOperatorAssembleLinearDiagonal` with {c:func}`CeedOperatorLinearAssembleDiagonal` for clarity. 82bcb2dfaeSJed Brown- Linear Operators can be assembled as point-block diagonal matrices with {c:func}`CeedOperatorLinearAssemblePointBlockDiagonal`, provided in row-major form in a {code}`ncomp` by {code}`ncomp` block per node. 83bcb2dfaeSJed Brown- Diagonal assemble interface changed to accept a {ref}`CeedVector` instead of a pointer to a {ref}`CeedVector` to reduce memory movement when interfacing with calling code. 84bcb2dfaeSJed Brown- Added {c:func}`CeedOperatorLinearAssembleAddDiagonal` and {c:func}`CeedOperatorLinearAssembleAddPointBlockDiagonal` for improved future integration with codes such as MFEM that compose the action of {ref}`CeedOperator`s external to libCEED. 85bcb2dfaeSJed Brown- Added {c:func}`CeedVectorTakeAray` to sync and remove libCEED read/write access to an allocated array and pass ownership of the array to the caller. 86bcb2dfaeSJed Brown This function is recommended over {c:func}`CeedVectorSyncArray` when the {code}`CeedVector` has an array owned by the caller that was set by {c:func}`CeedVectorSetArray`. 87bcb2dfaeSJed Brown- Added {code}`CeedQFunctionContext` object to manage user QFunction context data and reduce copies between device and host memory. 88bcb2dfaeSJed Brown- Added {c:func}`CeedOperatorMultigridLevelCreate`, {c:func}`CeedOperatorMultigridLevelCreateTensorH1`, and {c:func}`CeedOperatorMultigridLevelCreateH1` to facilitate creation of multigrid prolongation, restriction, and coarse grid operators using a common quadrature space. 89bcb2dfaeSJed Brown 90bcb2dfaeSJed Brown### New features 91bcb2dfaeSJed Brown 92bcb2dfaeSJed Brown- New HIP backend: `/gpu/hip/ref`. 93bcb2dfaeSJed Brown- CeedQFunction support for user `CUfunction`s in some backends 94bcb2dfaeSJed Brown 95bcb2dfaeSJed Brown### Performance improvements 96bcb2dfaeSJed Brown 97bcb2dfaeSJed Brown- OCCA backend rebuilt to facilitate future performance enhancements. 98bcb2dfaeSJed Brown- Petsc BPs suite improved to reduce noise due to multiple calls to {code}`mpiexec`. 99bcb2dfaeSJed Brown 100bcb2dfaeSJed Brown### Examples 101bcb2dfaeSJed Brown 102bcb2dfaeSJed Brown- {ref}`example-petsc-elasticity` example updated with strain energy computation and more flexible boundary conditions. 103bcb2dfaeSJed Brown 104bcb2dfaeSJed Brown### Deprecated backends 105bcb2dfaeSJed Brown 106bcb2dfaeSJed Brown- The `/gpu/cuda/reg` backend has been removed, with its core features moved into `/gpu/cuda/ref` and `/gpu/cuda/shared`. 107bcb2dfaeSJed Brown 108bcb2dfaeSJed Brown(v0-6)= 109bcb2dfaeSJed Brown 110bcb2dfaeSJed Brown## v0.6 (Mar 29, 2020) 111bcb2dfaeSJed Brown 112bcb2dfaeSJed BrownlibCEED v0.6 contains numerous new features and examples, as well as expanded 113bcb2dfaeSJed Browndocumentation in [this new website](https://libceed.readthedocs.io). 114bcb2dfaeSJed Brown 115bcb2dfaeSJed Brown### New features 116bcb2dfaeSJed Brown 117bcb2dfaeSJed Brown- New Python interface using [CFFI](https://cffi.readthedocs.io/) provides a nearly 118bcb2dfaeSJed Brown 1-1 correspondence with the C interface, plus some convenience features. For instance, 119bcb2dfaeSJed Brown data stored in the {cpp:type}`CeedVector` structure are available without copy as 120bcb2dfaeSJed Brown {py:class}`numpy.ndarray`. Short tutorials are provided in 121bcb2dfaeSJed Brown [Binder](https://mybinder.org/v2/gh/CEED/libCEED/main?urlpath=lab/tree/examples/tutorials/). 122bcb2dfaeSJed Brown- Linear QFunctions can be assembled as block-diagonal matrices (per quadrature point, 123bcb2dfaeSJed Brown {c:func}`CeedOperatorAssembleLinearQFunction`) or to evaluate the diagonal 124bcb2dfaeSJed Brown ({c:func}`CeedOperatorAssembleLinearDiagonal`). These operations are useful for 125bcb2dfaeSJed Brown preconditioning ingredients and are used in the libCEED's multigrid examples. 126bcb2dfaeSJed Brown- The inverse of separable operators can be obtained using 127bcb2dfaeSJed Brown {c:func}`CeedOperatorCreateFDMElementInverse` and applied with 128bcb2dfaeSJed Brown {c:func}`CeedOperatorApply`. This is a useful preconditioning ingredient, 129bcb2dfaeSJed Brown especially for Laplacians and related operators. 130bcb2dfaeSJed Brown- New functions: {c:func}`CeedVectorNorm`, {c:func}`CeedOperatorApplyAdd`, 131bcb2dfaeSJed Brown {c:func}`CeedQFunctionView`, {c:func}`CeedOperatorView`. 132bcb2dfaeSJed Brown- Make public accessors for various attributes to facilitate writing composable code. 133bcb2dfaeSJed Brown- New backend: `/cpu/self/memcheck/serial`. 134bcb2dfaeSJed Brown- QFunctions using variable-length array (VLA) pointer constructs can be used with CUDA 135bcb2dfaeSJed Brown backends. (Single source is coming soon for OCCA backends.) 136bcb2dfaeSJed Brown- Fix some missing edge cases in CUDA backend. 137bcb2dfaeSJed Brown 138bcb2dfaeSJed Brown### Performance Improvements 139bcb2dfaeSJed Brown 140bcb2dfaeSJed Brown- MAGMA backend performance optimization and non-tensor bases. 141bcb2dfaeSJed Brown- No-copy optimization in {c:func}`CeedOperatorApply`. 142bcb2dfaeSJed Brown 143bcb2dfaeSJed Brown### Interface changes 144bcb2dfaeSJed Brown 145bcb2dfaeSJed Brown- Replace {code}`CeedElemRestrictionCreateIdentity` and 146bcb2dfaeSJed Brown {code}`CeedElemRestrictionCreateBlocked` with more flexible 147bcb2dfaeSJed Brown {c:func}`CeedElemRestrictionCreateStrided` and 148bcb2dfaeSJed Brown {c:func}`CeedElemRestrictionCreateBlockedStrided`. 149bcb2dfaeSJed Brown- Add arguments to {c:func}`CeedQFunctionCreateIdentity`. 150bcb2dfaeSJed Brown- Replace ambiguous uses of {cpp:enum}`CeedTransposeMode` for L-vector identification 151bcb2dfaeSJed Brown with {cpp:enum}`CeedInterlaceMode`. This is now an attribute of the 152bcb2dfaeSJed Brown {cpp:type}`CeedElemRestriction` (see {c:func}`CeedElemRestrictionCreate`) and no 153bcb2dfaeSJed Brown longer passed as `lmode` arguments to {c:func}`CeedOperatorSetField` and 154bcb2dfaeSJed Brown {c:func}`CeedElemRestrictionApply`. 155bcb2dfaeSJed Brown 156bcb2dfaeSJed Brown### Examples 157bcb2dfaeSJed Brown 158bcb2dfaeSJed BrownlibCEED-0.6 contains greatly expanded examples with {ref}`new documentation <Examples>`. 159bcb2dfaeSJed BrownNotable additions include: 160bcb2dfaeSJed Brown 161bcb2dfaeSJed Brown- Standalone {ref}`ex2-surface` ({file}`examples/ceed/ex2-surface`): compute the area of 162bcb2dfaeSJed Brown a domain in 1, 2, and 3 dimensions by applying a Laplacian. 163bcb2dfaeSJed Brown 164bcb2dfaeSJed Brown- PETSc {ref}`example-petsc-area` ({file}`examples/petsc/area.c`): computes surface area 165bcb2dfaeSJed Brown of domains (like the cube and sphere) by direct integration on a surface mesh; 166bcb2dfaeSJed Brown demonstrates geometric dimension different from topological dimension. 167bcb2dfaeSJed Brown 168bcb2dfaeSJed Brown- PETSc {ref}`example-petsc-bps`: 169bcb2dfaeSJed Brown 170bcb2dfaeSJed Brown - {file}`examples/petsc/bpsraw.c` (formerly `bps.c`): transparent CUDA support. 171bcb2dfaeSJed Brown - {file}`examples/petsc/bps.c` (formerly `bpsdmplex.c`): performance improvements 172bcb2dfaeSJed Brown and transparent CUDA support. 173bcb2dfaeSJed Brown - {ref}`example-petsc-bps-sphere` ({file}`examples/petsc/bpssphere.c`): 174bcb2dfaeSJed Brown generalizations of all CEED BPs to the surface of the sphere; demonstrates geometric 175bcb2dfaeSJed Brown dimension different from topological dimension. 176bcb2dfaeSJed Brown 177bcb2dfaeSJed Brown- {ref}`example-petsc-multigrid` ({file}`examples/petsc/multigrid.c`): new p-multigrid 178bcb2dfaeSJed Brown solver with algebraic multigrid coarse solve. 179bcb2dfaeSJed Brown 180bcb2dfaeSJed Brown- {ref}`example-petsc-navier-stokes` ({file}`examples/fluids/navierstokes.c`; formerly 181bcb2dfaeSJed Brown `examples/navier-stokes`): unstructured grid support (using PETSc's `DMPlex`), 182bcb2dfaeSJed Brown implicit time integration, SU/SUPG stabilization, free-slip boundary conditions, and 183bcb2dfaeSJed Brown quasi-2D computational domain support. 184bcb2dfaeSJed Brown 185bcb2dfaeSJed Brown- {ref}`example-petsc-elasticity` ({file}`examples/solids/elasticity.c`): new solver for 186bcb2dfaeSJed Brown linear elasticity, small-strain hyperelasticity, and globalized finite-strain 187bcb2dfaeSJed Brown hyperelasticity using p-multigrid with algebraic multigrid coarse solve. 188bcb2dfaeSJed Brown 189bcb2dfaeSJed Brown(v0-5)= 190bcb2dfaeSJed Brown 191bcb2dfaeSJed Brown## v0.5 (Sep 18, 2019) 192bcb2dfaeSJed Brown 193bcb2dfaeSJed BrownFor this release, several improvements were made. Two new CUDA backends were added to 194bcb2dfaeSJed Brownthe family of backends, of which, the new `cuda-gen` backend achieves state-of-the-art 195bcb2dfaeSJed Brownperformance using single-source {ref}`CeedQFunction`. From this release, users 196bcb2dfaeSJed Browncan define Q-Functions in a single source code independently of the targeted backend 197bcb2dfaeSJed Brownwith the aid of a new macro `CEED QFUNCTION` to support JIT (Just-In-Time) and CPU 198bcb2dfaeSJed Browncompilation of the user provided {ref}`CeedQFunction` code. To allow a unified 199bcb2dfaeSJed Browndeclaration, the {ref}`CeedQFunction` API has undergone a slight change: 200bcb2dfaeSJed Brownthe `QFunctionField` parameter `ncomp` has been changed to `size`. This change 201bcb2dfaeSJed Brownrequires setting the previous value of `ncomp` to `ncomp*dim` when adding a 202bcb2dfaeSJed Brown`QFunctionField` with eval mode `CEED EVAL GRAD`. 203bcb2dfaeSJed Brown 204bcb2dfaeSJed BrownAdditionally, new CPU backends 205bcb2dfaeSJed Brownwere included in this release, such as the `/cpu/self/opt/*` backends (which are 206bcb2dfaeSJed Brownwritten in pure C and use partial **E-vectors** to improve performance) and the 207bcb2dfaeSJed Brown`/cpu/self/ref/memcheck` backend (which relies upon the 208bcb2dfaeSJed Brown[Valgrind](http://valgrind.org/) Memcheck tool to help verify that user 209bcb2dfaeSJed Brown{ref}`CeedQFunction` have no undefined values). 210bcb2dfaeSJed BrownThis release also included various performance improvements, bug fixes, new examples, 211bcb2dfaeSJed Brownand improved tests. Among these improvements, vectorized instructions for 212bcb2dfaeSJed Brown{ref}`CeedQFunction` code compiled for CPU were enhanced by using `CeedPragmaSIMD` 213bcb2dfaeSJed Browninstead of `CeedPragmaOMP`, implementation of a {ref}`CeedQFunction` gallery and 214bcb2dfaeSJed Brownidentity Q-Functions were introduced, and the PETSc benchmark problems were expanded 215bcb2dfaeSJed Brownto include unstructured meshes handling were. For this expansion, the prior version of 216bcb2dfaeSJed Brownthe PETSc BPs, which only included data associated with structured geometries, were 217bcb2dfaeSJed Brownrenamed `bpsraw`, and the new version of the BPs, which can handle data associated 218bcb2dfaeSJed Brownwith any unstructured geometry, were called `bps`. Additionally, other benchmark 219bcb2dfaeSJed Brownproblems, namely BP2 and BP4 (the vector-valued versions of BP1 and BP3, respectively), 220bcb2dfaeSJed Brownand BP5 and BP6 (the collocated versions---for which the quadrature points are the same 221bcb2dfaeSJed Brownas the Gauss Lobatto nodes---of BP3 and BP4 respectively) were added to the PETSc 222bcb2dfaeSJed Brownexamples. Furthermoew, another standalone libCEED example, called `ex2`, which 223bcb2dfaeSJed Browncomputes the surface area of a given mesh was added to this release. 224bcb2dfaeSJed Brown 225bcb2dfaeSJed BrownBackends available in this release: 226bcb2dfaeSJed Brown 22768e843eeSJed Brown| CEED resource (`-ceed`) | Backend | 22868e843eeSJed Brown|--------------------------|-----------------------------------------------------| 22968e843eeSJed Brown| `/cpu/self/ref/serial` | Serial reference implementation | 23068e843eeSJed Brown| `/cpu/self/ref/blocked` | Blocked reference implementation | 23168e843eeSJed Brown| `/cpu/self/ref/memcheck` | Memcheck backend, undefined value checks | 23268e843eeSJed Brown| `/cpu/self/opt/serial` | Serial optimized C implementation | 23368e843eeSJed Brown| `/cpu/self/opt/blocked` | Blocked optimized C implementation | 23468e843eeSJed Brown| `/cpu/self/avx/serial` | Serial AVX implementation | 23568e843eeSJed Brown| `/cpu/self/avx/blocked` | Blocked AVX implementation | 23668e843eeSJed Brown| `/cpu/self/xsmm/serial` | Serial LIBXSMM implementation | 23768e843eeSJed Brown| `/cpu/self/xsmm/blocked` | Blocked LIBXSMM implementation | 23868e843eeSJed Brown| `/cpu/occa` | Serial OCCA kernels | 23968e843eeSJed Brown| `/gpu/occa` | CUDA OCCA kernels | 24068e843eeSJed Brown| `/omp/occa` | OpenMP OCCA kernels | 24168e843eeSJed Brown| `/ocl/occa` | OpenCL OCCA kernels | 24268e843eeSJed Brown| `/gpu/cuda/ref` | Reference pure CUDA kernels | 24368e843eeSJed Brown| `/gpu/cuda/reg` | Pure CUDA kernels using one thread per element | 24468e843eeSJed Brown| `/gpu/cuda/shared` | Optimized pure CUDA kernels using shared memory | 24568e843eeSJed Brown| `/gpu/cuda/gen` | Optimized pure CUDA kernels using code generation | 24668e843eeSJed Brown| `/gpu/magma` | CUDA MAGMA kernels | 247bcb2dfaeSJed Brown 248bcb2dfaeSJed BrownExamples available in this release: 249bcb2dfaeSJed Brown 25068e843eeSJed Brown:::{list-table} 25168e843eeSJed Brown:header-rows: 1 25268e843eeSJed Brown:widths: auto 25368e843eeSJed Brown* - User code 25468e843eeSJed Brown - Example 25568e843eeSJed Brown* - `ceed` 25668e843eeSJed Brown - * ex1 (volume) 25768e843eeSJed Brown * ex2 (surface) 25868e843eeSJed Brown* - `mfem` 25968e843eeSJed Brown - * BP1 (scalar mass operator) 26068e843eeSJed Brown * BP3 (scalar Laplace operator) 26168e843eeSJed Brown* - `petsc` 26268e843eeSJed Brown - * BP1 (scalar mass operator) 26368e843eeSJed Brown * BP2 (vector mass operator) 26468e843eeSJed Brown * BP3 (scalar Laplace operator) 26568e843eeSJed Brown * BP4 (vector Laplace operator) 26668e843eeSJed Brown * BP5 (collocated scalar Laplace operator) 26768e843eeSJed Brown * BP6 (collocated vector Laplace operator) 26868e843eeSJed Brown * Navier-Stokes 26968e843eeSJed Brown* - `nek5000` 27068e843eeSJed Brown - * BP1 (scalar mass operator) 27168e843eeSJed Brown * BP3 (scalar Laplace operator) 27268e843eeSJed Brown::: 273bcb2dfaeSJed Brown 274bcb2dfaeSJed Brown(v0-4)= 275bcb2dfaeSJed Brown 276bcb2dfaeSJed Brown## v0.4 (Apr 1, 2019) 277bcb2dfaeSJed Brown 278bcb2dfaeSJed BrownlibCEED v0.4 was made again publicly available in the second full CEED software 279bcb2dfaeSJed Browndistribution, release CEED 2.0. This release contained notable features, such as 280bcb2dfaeSJed Brownfour new CPU backends, two new GPU backends, CPU backend optimizations, initial 281bcb2dfaeSJed Brownsupport for operator composition, performance benchmarking, and a Navier-Stokes demo. 282bcb2dfaeSJed BrownThe new CPU backends in this release came in two families. The `/cpu/self/*/serial` 283bcb2dfaeSJed Brownbackends process one element at a time and are intended for meshes with a smaller number 284bcb2dfaeSJed Brownof high order elements. The `/cpu/self/*/blocked` backends process blocked batches of 285bcb2dfaeSJed Browneight interlaced elements and are intended for meshes with higher numbers of elements. 286bcb2dfaeSJed BrownThe `/cpu/self/avx/*` backends rely upon AVX instructions to provide vectorized CPU 287bcb2dfaeSJed Brownperformance. The `/cpu/self/xsmm/*` backends rely upon the 288bcb2dfaeSJed Brown[LIBXSMM](http://github.com/hfp/libxsmm) package to provide vectorized CPU 289bcb2dfaeSJed Brownperformance. The `/gpu/cuda/*` backends provide GPU performance strictly using CUDA. 290bcb2dfaeSJed BrownThe `/gpu/cuda/ref` backend is a reference CUDA backend, providing reasonable 291bcb2dfaeSJed Brownperformance for most problem configurations. The `/gpu/cuda/reg` backend uses a simple 292bcb2dfaeSJed Brownparallelization approach, where each thread treats a finite element. Using just in time 293bcb2dfaeSJed Browncompilation, provided by nvrtc (NVidia Runtime Compiler), and runtime parameters, this 294bcb2dfaeSJed Brownbackend unroll loops and map memory address to registers. The `/gpu/cuda/reg` backend 295bcb2dfaeSJed Brownachieve good peak performance for 1D, 2D, and low order 3D problems, but performance 296bcb2dfaeSJed Browndeteriorates very quickly when threads run out of registers. 297bcb2dfaeSJed Brown 298bcb2dfaeSJed BrownA new explicit time-stepping Navier-Stokes solver was added to the family of libCEED 299bcb2dfaeSJed Brownexamples in the `examples/petsc` directory (see {ref}`example-petsc-navier-stokes`). 300bcb2dfaeSJed BrownThis example solves the time-dependent Navier-Stokes equations of compressible gas 301bcb2dfaeSJed Browndynamics in a static Eulerian three-dimensional frame, using structured high-order 302bcb2dfaeSJed Brownfinite/spectral element spatial discretizations and explicit high-order time-stepping 303bcb2dfaeSJed Brown(available in PETSc). Moreover, the Navier-Stokes example was developed using PETSc, 304bcb2dfaeSJed Brownso that the pointwise physics (defined at quadrature points) is separated from the 305bcb2dfaeSJed Brownparallelization and meshing concerns. 306bcb2dfaeSJed Brown 307bcb2dfaeSJed BrownBackends available in this release: 308bcb2dfaeSJed Brown 30968e843eeSJed Brown| CEED resource (`-ceed`) | Backend | 31068e843eeSJed Brown|--------------------------|-----------------------------------------------------| 31168e843eeSJed Brown| `/cpu/self/ref/serial` | Serial reference implementation | 31268e843eeSJed Brown| `/cpu/self/ref/blocked` | Blocked reference implementation | 31368e843eeSJed Brown| `/cpu/self/tmpl` | Backend template, defaults to `/cpu/self/blocked` | 31468e843eeSJed Brown| `/cpu/self/avx/serial` | Serial AVX implementation | 31568e843eeSJed Brown| `/cpu/self/avx/blocked` | Blocked AVX implementation | 31668e843eeSJed Brown| `/cpu/self/xsmm/serial` | Serial LIBXSMM implementation | 31768e843eeSJed Brown| `/cpu/self/xsmm/blocked` | Blocked LIBXSMM implementation | 31868e843eeSJed Brown| `/cpu/occa` | Serial OCCA kernels | 31968e843eeSJed Brown| `/gpu/occa` | CUDA OCCA kernels | 32068e843eeSJed Brown| `/omp/occa` | OpenMP OCCA kernels | 32168e843eeSJed Brown| `/ocl/occa` | OpenCL OCCA kernels | 32268e843eeSJed Brown| `/gpu/cuda/ref` | Reference pure CUDA kernels | 32368e843eeSJed Brown| `/gpu/cuda/reg` | Pure CUDA kernels using one thread per element | 32468e843eeSJed Brown| `/gpu/magma` | CUDA MAGMA kernels | 325bcb2dfaeSJed Brown 326bcb2dfaeSJed BrownExamples available in this release: 327bcb2dfaeSJed Brown 32868e843eeSJed Brown:::{list-table} 32968e843eeSJed Brown:header-rows: 1 33068e843eeSJed Brown:widths: auto 33168e843eeSJed Brown* - User code 33268e843eeSJed Brown - Example 33368e843eeSJed Brown* - `ceed` 33468e843eeSJed Brown - * ex1 (volume) 33568e843eeSJed Brown* - `mfem` 33668e843eeSJed Brown - * BP1 (scalar mass operator) 33768e843eeSJed Brown * BP3 (scalar Laplace operator) 33868e843eeSJed Brown* - `petsc` 33968e843eeSJed Brown - * BP1 (scalar mass operator) 34068e843eeSJed Brown * BP3 (scalar Laplace operator) 34168e843eeSJed Brown * Navier-Stokes 34268e843eeSJed Brown* - `nek5000` 34368e843eeSJed Brown - * BP1 (scalar mass operator) 34468e843eeSJed Brown * BP3 (scalar Laplace operator) 34568e843eeSJed Brown::: 346bcb2dfaeSJed Brown 347bcb2dfaeSJed Brown(v0-3)= 348bcb2dfaeSJed Brown 349bcb2dfaeSJed Brown## v0.3 (Sep 30, 2018) 350bcb2dfaeSJed Brown 351bcb2dfaeSJed BrownNotable features in this release include active/passive field interface, support for 352bcb2dfaeSJed Brownnon-tensor bases, backend optimization, and improved Fortran interface. This release 353bcb2dfaeSJed Brownalso focused on providing improved continuous integration, and many new tests with code 354bcb2dfaeSJed Browncoverage reports of about 90%. This release also provided a significant change to the 355bcb2dfaeSJed Brownpublic interface: a {ref}`CeedQFunction` can take any number of named input and output 356bcb2dfaeSJed Brownarguments while {ref}`CeedOperator` connects them to the actual data, which may be 357bcb2dfaeSJed Brownsupplied explicitly to `CeedOperatorApply()` (active) or separately via 358bcb2dfaeSJed Brown`CeedOperatorSetField()` (passive). This interface change enables reusable libraries 359bcb2dfaeSJed Brownof CeedQFunctions and composition of block solvers constructed using 360bcb2dfaeSJed Brown{ref}`CeedOperator`. A concept of blocked restriction was added to this release and 361bcb2dfaeSJed Brownused in an optimized CPU backend. Although this is typically not visible to the user, 362bcb2dfaeSJed Brownit enables effective use of arbitrary-length SIMD while maintaining cache locality. 363bcb2dfaeSJed BrownThis CPU backend also implements an algebraic factorization of tensor product gradients 364bcb2dfaeSJed Brownto perform fewer operations than standard application of interpolation and 365bcb2dfaeSJed Browndifferentiation from nodes to quadrature points. This algebraic formulation 366bcb2dfaeSJed Brownautomatically supports non-polynomial and non-interpolatory bases, thus is more general 367bcb2dfaeSJed Brownthan the more common derivation in terms of Lagrange polynomials on the quadrature points. 368bcb2dfaeSJed Brown 369bcb2dfaeSJed BrownBackends available in this release: 370bcb2dfaeSJed Brown 37168e843eeSJed Brown| CEED resource (`-ceed`) | Backend | 37268e843eeSJed Brown|-------------------------|-----------------------------------------------------| 37368e843eeSJed Brown| `/cpu/self/blocked` | Blocked reference implementation | 37468e843eeSJed Brown| `/cpu/self/ref` | Serial reference implementation | 37568e843eeSJed Brown| `/cpu/self/tmpl` | Backend template, defaults to `/cpu/self/blocked` | 37668e843eeSJed Brown| `/cpu/occa` | Serial OCCA kernels | 37768e843eeSJed Brown| `/gpu/occa` | CUDA OCCA kernels | 37868e843eeSJed Brown| `/omp/occa` | OpenMP OCCA kernels | 37968e843eeSJed Brown| `/ocl/occa` | OpenCL OCCA kernels | 38068e843eeSJed Brown| `/gpu/magma` | CUDA MAGMA kernels | 381bcb2dfaeSJed Brown 382bcb2dfaeSJed BrownExamples available in this release: 383bcb2dfaeSJed Brown 38468e843eeSJed Brown:::{list-table} 38568e843eeSJed Brown:header-rows: 1 38668e843eeSJed Brown:widths: auto 38768e843eeSJed Brown* - User code 38868e843eeSJed Brown - Example 38968e843eeSJed Brown* - `ceed` 39068e843eeSJed Brown - * ex1 (volume) 39168e843eeSJed Brown* - `mfem` 39268e843eeSJed Brown - * BP1 (scalar mass operator) 39368e843eeSJed Brown * BP3 (scalar Laplace operator) 39468e843eeSJed Brown* - `petsc` 39568e843eeSJed Brown - * BP1 (scalar mass operator) 39668e843eeSJed Brown * BP3 (scalar Laplace operator) 39768e843eeSJed Brown* - `nek5000` 39868e843eeSJed Brown - * BP1 (scalar mass operator) 39968e843eeSJed Brown * BP3 (scalar Laplace operator) 40068e843eeSJed Brown::: 401bcb2dfaeSJed Brown 402bcb2dfaeSJed Brown(v0-21)= 403bcb2dfaeSJed Brown 404bcb2dfaeSJed Brown## v0.21 (Sep 30, 2018) 405bcb2dfaeSJed Brown 406bcb2dfaeSJed BrownA MAGMA backend (which relies upon the 407bcb2dfaeSJed Brown[MAGMA](https://bitbucket.org/icl/magma) package) was integrated in libCEED for this 408bcb2dfaeSJed Brownrelease. This initial integration set up the framework of using MAGMA and provided the 409bcb2dfaeSJed BrownlibCEED functionality through MAGMA kernels as one of libCEED’s computational backends. 410bcb2dfaeSJed BrownAs any other backend, the MAGMA backend provides extended basic data structures for 411bcb2dfaeSJed Brown{ref}`CeedVector`, {ref}`CeedElemRestriction`, and {ref}`CeedOperator`, and implements 412bcb2dfaeSJed Brownthe fundamental CEED building blocks to work with the new data structures. 413bcb2dfaeSJed BrownIn general, the MAGMA-specific data structures keep the libCEED pointers to CPU data 414bcb2dfaeSJed Brownbut also add corresponding device (e.g., GPU) pointers to the data. Coherency is handled 415bcb2dfaeSJed Browninternally, and thus seamlessly to the user, through the functions/methods that are 416bcb2dfaeSJed Brownprovided to support them. 417bcb2dfaeSJed Brown 418bcb2dfaeSJed BrownBackends available in this release: 419bcb2dfaeSJed Brown 42068e843eeSJed Brown| CEED resource (`-ceed`) | Backend | 42168e843eeSJed Brown|-------------------------|---------------------------------| 42268e843eeSJed Brown| `/cpu/self` | Serial reference implementation | 42368e843eeSJed Brown| `/cpu/occa` | Serial OCCA kernels | 42468e843eeSJed Brown| `/gpu/occa` | CUDA OCCA kernels | 42568e843eeSJed Brown| `/omp/occa` | OpenMP OCCA kernels | 42668e843eeSJed Brown| `/ocl/occa` | OpenCL OCCA kernels | 42768e843eeSJed Brown| `/gpu/magma` | CUDA MAGMA kernels | 428bcb2dfaeSJed Brown 429bcb2dfaeSJed BrownExamples available in this release: 430bcb2dfaeSJed Brown 43168e843eeSJed Brown:::{list-table} 43268e843eeSJed Brown:header-rows: 1 43368e843eeSJed Brown:widths: auto 43468e843eeSJed Brown* - User code 43568e843eeSJed Brown - Example 43668e843eeSJed Brown* - `ceed` 43768e843eeSJed Brown - * ex1 (volume) 43868e843eeSJed Brown* - `mfem` 43968e843eeSJed Brown - * BP1 (scalar mass operator) 44068e843eeSJed Brown * BP3 (scalar Laplace operator) 44168e843eeSJed Brown* - `petsc` 44268e843eeSJed Brown - * BP1 (scalar mass operator) 44368e843eeSJed Brown* - `nek5000` 44468e843eeSJed Brown - * BP1 (scalar mass operator) 44568e843eeSJed Brown::: 446bcb2dfaeSJed Brown 447bcb2dfaeSJed Brown(v0-2)= 448bcb2dfaeSJed Brown 449bcb2dfaeSJed Brown## v0.2 (Mar 30, 2018) 450bcb2dfaeSJed Brown 451bcb2dfaeSJed BrownlibCEED was made publicly available the first full CEED software distribution, release 452bcb2dfaeSJed BrownCEED 1.0. The distribution was made available using the Spack package manager to provide 453bcb2dfaeSJed Browna common, easy-to-use build environment, where the user can build the CEED distribution 454bcb2dfaeSJed Brownwith all dependencies. This release included a new Fortran interface for the library. 455bcb2dfaeSJed BrownThis release also contained major improvements in the OCCA backend (including a new 456bcb2dfaeSJed Brown`/ocl/occa` backend) and new examples. The standalone libCEED example was modified to 457bcb2dfaeSJed Browncompute the volume volume of a given mesh (in 1D, 2D, or 3D) and placed in an 458bcb2dfaeSJed Brown`examples/ceed` subfolder. A new `mfem` example to perform BP3 (with the application 459bcb2dfaeSJed Brownof the Laplace operator) was also added to this release. 460bcb2dfaeSJed Brown 461bcb2dfaeSJed BrownBackends available in this release: 462bcb2dfaeSJed Brown 46368e843eeSJed Brown| CEED resource (`-ceed`) | Backend | 46468e843eeSJed Brown|-------------------------|---------------------------------| 46568e843eeSJed Brown| `/cpu/self` | Serial reference implementation | 46668e843eeSJed Brown| `/cpu/occa` | Serial OCCA kernels | 46768e843eeSJed Brown| `/gpu/occa` | CUDA OCCA kernels | 46868e843eeSJed Brown| `/omp/occa` | OpenMP OCCA kernels | 46968e843eeSJed Brown| `/ocl/occa` | OpenCL OCCA kernels | 470bcb2dfaeSJed Brown 471bcb2dfaeSJed BrownExamples available in this release: 472bcb2dfaeSJed Brown 47368e843eeSJed Brown:::{list-table} 47468e843eeSJed Brown:header-rows: 1 47568e843eeSJed Brown:widths: auto 47668e843eeSJed Brown* - User code 47768e843eeSJed Brown - Example 47868e843eeSJed Brown* - `ceed` 47968e843eeSJed Brown - * ex1 (volume) 48068e843eeSJed Brown* - `mfem` 48168e843eeSJed Brown - * BP1 (scalar mass operator) 48268e843eeSJed Brown * BP3 (scalar Laplace operator) 48368e843eeSJed Brown* - `petsc` 48468e843eeSJed Brown - * BP1 (scalar mass operator) 48568e843eeSJed Brown* - `nek5000` 48668e843eeSJed Brown - * BP1 (scalar mass operator) 48768e843eeSJed Brown::: 488bcb2dfaeSJed Brown 489bcb2dfaeSJed Brown(v0-1)= 490bcb2dfaeSJed Brown 491bcb2dfaeSJed Brown## v0.1 (Jan 3, 2018) 492bcb2dfaeSJed Brown 493bcb2dfaeSJed BrownInitial low-level API of the CEED project. The low-level API provides a set of Finite 494bcb2dfaeSJed BrownElements kernels and components for writing new low-level kernels. Examples include: 495bcb2dfaeSJed Brownvector and sparse linear algebra, element matrix assembly over a batch of elements, 496bcb2dfaeSJed Brownpartial assembly and action for efficient high-order operators like mass, diffusion, 497bcb2dfaeSJed Brownadvection, etc. The main goal of the low-level API is to establish the basis for the 498bcb2dfaeSJed Brownhigh-level API. Also, identifying such low-level kernels and providing a reference 499bcb2dfaeSJed Brownimplementation for them serves as the basis for specialized backend implementations. 500bcb2dfaeSJed BrownThis release contained several backends: `/cpu/self`, and backends which rely upon the 501bcb2dfaeSJed Brown[OCCA](http://github.com/libocca/occa) package, such as `/cpu/occa`, 502bcb2dfaeSJed Brown`/gpu/occa`, and `/omp/occa`. 503bcb2dfaeSJed BrownIt also included several examples, in the `examples` folder: 504bcb2dfaeSJed BrownA standalone code that shows the usage of libCEED (with no external 505bcb2dfaeSJed Browndependencies) to apply the Laplace operator, `ex1`; an `mfem` example to perform BP1 506bcb2dfaeSJed Brown(with the application of the mass operator); and a `petsc` example to perform BP1 507bcb2dfaeSJed Brown(with the application of the mass operator). 508bcb2dfaeSJed Brown 509bcb2dfaeSJed BrownBackends available in this release: 510bcb2dfaeSJed Brown 51168e843eeSJed Brown| CEED resource (`-ceed`) | Backend | 51268e843eeSJed Brown|-------------------------|---------------------------------| 51368e843eeSJed Brown| `/cpu/self` | Serial reference implementation | 51468e843eeSJed Brown| `/cpu/occa` | Serial OCCA kernels | 51568e843eeSJed Brown| `/gpu/occa` | CUDA OCCA kernels | 51668e843eeSJed Brown| `/omp/occa` | OpenMP OCCA kernels | 517bcb2dfaeSJed Brown 518bcb2dfaeSJed BrownExamples available in this release: 519bcb2dfaeSJed Brown 520bcb2dfaeSJed Brown| User code | Example | 52168e843eeSJed Brown|-----------------------|-----------------------------------| 52268e843eeSJed Brown| `ceed` | ex1 (scalar Laplace operator) | 52368e843eeSJed Brown| `mfem` | BP1 (scalar mass operator) | 52468e843eeSJed Brown| `petsc` | BP1 (scalar mass operator) | 525bcb2dfaeSJed Brown``` 526