1# Changes/Release Notes 2 3On this page we provide a summary of the main API changes, new features and examples for each release of libCEED. 4 5(main)= 6 7## Current `main` branch 8 9### Bugfix 10 11- Fix bug in setting device id for GPU backends. 12 13### Interface changes 14 15- Added {c:func}`CeedOperatorSetName` for more readable {c:func}`CeedOperatorView` output. 16 17### New features 18 19- Update `/cpu/self/memcheck/*` backends to help verify `CeedQFunctionContext` data sizes provided by user. 20 21### Bugfix 22 23- Fix storing of indices for `CeedElemRestriction` on the host with GPU backends. 24- Fix `CeedElemRestriction` sizing for {c:func}`CeedOperatorAssemblePointBlockDiagonal`. 25- Fix bugs in CPU implementation of {c:func}`CeedOperatorLinearAssemble` when there are different number of active input modes and active output modes. 26 27### Examples 28 29- Added various performance enhancements for {ref}`example-petsc-navier-stokes` 30- Refactored {ref}`example-petsc-navier-stokes` to improve code reuse 31- Added Shock Tube, Channel, and Flat Plate boundary layer problems to {ref}`example-petsc-navier-stokes` 32 33(v0-10-1)= 34 35## v0.10.1 (Apr 11, 2022) 36 37### Interface changes 38 39- Added {c:func}`CeedQFunctionSetUserFlopsEstimate` and {c:func}`CeedOperatorGetFlopsEstimate` to facilitate estimating FLOPs in operator application. 40 41### Bugfix 42 43- Install JiT source files in install directory to fix GPU functionality for installed libCEED. 44 45(v0-10)= 46 47## v0.10 (Mar 21, 2022) 48 49### Interface changes 50 51- Update {c:func}`CeedQFunctionGetFields` and {c:func}`CeedOperatorGetFields` to include number of fields. 52- Promote to the public API: QFunction and Operator field objects, `CeedQFunctionField` and `CeedOperatorField`, and associated getters, {c:func}`CeedQFunctionGetFields`; {c:func}`CeedQFunctionFieldGetName`; {c:func}`CeedQFunctionFieldGetSize`; {c:func}`CeedQFunctionFieldGetEvalMode`; {c:func}`CeedOperatorGetFields`; {c:func}`CeedOperatorFieldGetElemRestriction`; {c:func}`CeedOperatorFieldGetBasis`; and {c:func}`CeedOperatorFieldGetVector`. 53- Clarify and document conditions where `CeedQFunction` and `CeedOperator` become immutable and no further fields or suboperators can be added. 54- Add {c:func}`CeedOperatorLinearAssembleQFunctionBuildOrUpdate` to reduce object creation overhead in assembly of CeedOperator preconditioning ingredients. 55- Promote {c:func}`CeedOperatorCheckReady`to the public API to facilitate interactive interfaces. 56- Warning added when compiling OCCA backend to alert users that this backend is experimental. 57- `ceed-backend.h`, `ceed-hash.h`, and `ceed-khash.h` removed. Users should use `ceed/backend.h`, `ceed/hash.h`, and `ceed/khash.h`. 58- Added {c:func}`CeedQFunctionGetKernelName`; refactored {c:func}`CeedQFunctionGetSourcePath` to exclude function kernel name. 59- Clarify documentation for {c:func}`CeedVectorTakeArray`; this function will error if {c:func}`CeedVectorSetArray` with `copy_mode == CEED_USE_POINTER` was not previously called for the corresponding `CeedMemType`. 60- Added {c:func}`CeedVectorGetArrayWrite` that allows access to uninitalized arrays; require initalized data for {c:func}`CeedVectorGetArray`. 61- Added {c:func}`CeedQFunctionContextRegisterDouble` and {c:func}`CeedQFunctionContextRegisterInt32` with {c:func}`CeedQFunctionContextSetDouble` and {c:func}`CeedQFunctionContextSetInt32` to facilitate easy updating of {c:struct}`CeedQFunctionContext` data by user defined field names. 62- Added {c:func}`CeedQFunctionContextGetFieldDescriptions` to retreive user defined descriptions of fields that are registered with `CeedQFunctionContextRegister*`. 63- Renamed `CeedElemTopology` entries for clearer namespacing between libCEED enums. 64- Added type `CeedSize` equivalent to `ptrdiff_t` for array sizes in {c:func}`CeedVectorCreate`, {c:func}`CeedVectorGetLength`, `CeedElemRestrictionCreate*`, {c:func}`CeedElemRestrictionGetLVectorSize`, and {c:func}`CeedOperatorLinearAssembleSymbolic`. This is a breaking change. 65- Added {c:func}`CeedOperatorSetQFunctionUpdated` to facilitate QFunction data re-use between operators sharing the same quadrature space, such as in a multigrid hierarchy. 66- Added {c:func}`CeedOperatorGetActiveVectorLengths` to get shape of CeedOperator. 67 68### New features 69 70- `CeedScalar` can now be set as `float` or `double` at compile time. 71- Added JiT utilities in `ceed/jit-tools.h` to reduce duplicated code in GPU backends. 72- Added support for JiT of QFunctions with `#include "relative/path/local-file.h"` statements for additional local files. Note that files included with `""` are searched relative to the current file first, then by compiler paths (as with `<>` includes). To use this feature, one should adhere to relative paths only, not compiler flags like `-I`, which the JiT will not be aware of. 73- Remove need to guard library headers in QFunction source for code generation backends. 74- `CeedDebugEnv()` macro created to provide debugging outputs when Ceed context is not present. 75- Added {c:func}`CeedStringAllocCopy` to reduce repeated code for copying strings internally. 76- Added {c:func}`CeedPathConcatenate` to facilitate loading kernel source files with a path relative to the current file. 77- Added support for non-tensor H(div) elements, to include CPU backend implementations and {c:func}`CeedBasisCreateHdiv` convenience constructor. 78- Added {c:func}`CeedQFunctionSetContextWritable` and read-only access to `CeedQFunctionContext` data as an optional feature to improve GPU performance. By default, calling the `CeedQFunctionUser` during {c:func}`CeedQFunctionApply` is assumed to write into the `CeedQFunctionContext` data, consistent with the previous behavior. Note that if a user asserts that their `CeedQFunctionUser` does not write into the `CeedQFunctionContext` data, they are responsible for the validity of this assertion. 79- Added support for element matrix assembly in GPU backends. 80 81### Maintainability 82 83- Refactored preconditioner support internally to facilitate future development and improve GPU completeness/test coverage. 84- `Include-what-you-use` makefile target added as `make iwyu`. 85- Create backend constant `CEED_FIELD_MAX` to reduce magic numbers in codebase. 86- Put GPU JiTed kernel source code into separate files. 87- Dropped legacy version support in PETSc based examples to better utilize PETSc DMPlex and Mat updates to support libCEED; current minimum PETSc version for the examples is v3.17. 88 89(v0-9)= 90 91## v0.9 (Jul 6, 2021) 92 93### Interface changes 94 95- Minor modification in error handling macro to silence pedantic warnings when compiling with Clang, but no functional impact. 96 97### New features 98 99- Add {c:func}`CeedVectorAXPY` and {c:func}`CeedVectorPointwiseMult` as a convenience for stand-alone testing and internal use. 100- Add `CEED_QFUNCTION_HELPER` macro to properly annotate QFunction helper functions for code generation backends. 101- Add `CeedPragmaOptimizeOff` macro for code that is sensitive to floating point errors from fast math optimizations. 102- Rust support: split `libceed-sys` crate out of `libceed` and [publish both on crates.io](https://crates.io/crates/libceed). 103 104### Performance improvements 105 106### Examples 107 108- Solid mechanics mini-app updated to explore the performance impacts of various formulations in the initial and current configurations. 109- Fluid mechanics example adds GPU support and improves modularity. 110 111### Deprecated backends 112 113- 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. 114 115(v0-8)= 116 117## v0.8 (Mar 31, 2021) 118 119### Interface changes 120 121- Error handling improved to include enumerated error codes for C interface return values. 122- 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. 123 124### New features 125 126- Julia and Rust interfaces added, providing a nearly 1-1 correspondence with the C interface, plus some convenience features. 127- Static libraries can be built with `make STATIC=1` and the pkg-config file is installed accordingly. 128- Add {c:func}`CeedOperatorLinearAssembleSymbolic` and {c:func}`CeedOperatorLinearAssemble` to support full assembly of libCEED operators. 129 130### Performance improvements 131 132- New HIP MAGMA backends for hipMAGMA library users: `/gpu/hip/magma` and `/gpu/hip/magma/det`. 133- New HIP backends for improved tensor basis performance: `/gpu/hip/shared` and `/gpu/hip/gen`. 134 135### Examples 136 137- {ref}`example-petsc-elasticity` example updated with traction boundary conditions and improved Dirichlet boundary conditions. 138- {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. 139- {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. 140- {ref}`example-petsc-navier-stokes` example updated with support for performing convergence study and plotting order of convergence by polynomial degree. 141 142(v0-7)= 143 144## v0.7 (Sep 29, 2020) 145 146### Interface changes 147 148- Replace limited {code}`CeedInterlaceMode` with more flexible component stride {code}`compstride` in {code}`CeedElemRestriction` constructors. 149 As a result, the {code}`indices` parameter has been replaced with {code}`offsets` and the {code}`nnodes` parameter has been replaced with {code}`lsize`. 150 These changes improve support for mixed finite element methods. 151- Replace various uses of {code}`Ceed*Get*Status` with {code}`Ceed*Is*` in the backend API to match common nomenclature. 152- Replace {code}`CeedOperatorAssembleLinearDiagonal` with {c:func}`CeedOperatorLinearAssembleDiagonal` for clarity. 153- 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. 154- 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. 155- 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. 156- 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. 157 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`. 158- Added {code}`CeedQFunctionContext` object to manage user QFunction context data and reduce copies between device and host memory. 159- 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. 160 161### New features 162 163- New HIP backend: `/gpu/hip/ref`. 164- CeedQFunction support for user `CUfunction`s in some backends 165 166### Performance improvements 167 168- OCCA backend rebuilt to facilitate future performance enhancements. 169- Petsc BPs suite improved to reduce noise due to multiple calls to {code}`mpiexec`. 170 171### Examples 172 173- {ref}`example-petsc-elasticity` example updated with strain energy computation and more flexible boundary conditions. 174 175### Deprecated backends 176 177- The `/gpu/cuda/reg` backend has been removed, with its core features moved into `/gpu/cuda/ref` and `/gpu/cuda/shared`. 178 179(v0-6)= 180 181## v0.6 (Mar 29, 2020) 182 183libCEED v0.6 contains numerous new features and examples, as well as expanded 184documentation in [this new website](https://libceed.org). 185 186### New features 187 188- New Python interface using [CFFI](https://cffi.readthedocs.io/) provides a nearly 189 1-1 correspondence with the C interface, plus some convenience features. For instance, 190 data stored in the {cpp:type}`CeedVector` structure are available without copy as 191 {py:class}`numpy.ndarray`. Short tutorials are provided in 192 [Binder](https://mybinder.org/v2/gh/CEED/libCEED/main?urlpath=lab/tree/examples/tutorials/). 193- Linear QFunctions can be assembled as block-diagonal matrices (per quadrature point, 194 {c:func}`CeedOperatorAssembleLinearQFunction`) or to evaluate the diagonal 195 ({c:func}`CeedOperatorAssembleLinearDiagonal`). These operations are useful for 196 preconditioning ingredients and are used in the libCEED's multigrid examples. 197- The inverse of separable operators can be obtained using 198 {c:func}`CeedOperatorCreateFDMElementInverse` and applied with 199 {c:func}`CeedOperatorApply`. This is a useful preconditioning ingredient, 200 especially for Laplacians and related operators. 201- New functions: {c:func}`CeedVectorNorm`, {c:func}`CeedOperatorApplyAdd`, 202 {c:func}`CeedQFunctionView`, {c:func}`CeedOperatorView`. 203- Make public accessors for various attributes to facilitate writing composable code. 204- New backend: `/cpu/self/memcheck/serial`. 205- QFunctions using variable-length array (VLA) pointer constructs can be used with CUDA 206 backends. (Single source is coming soon for OCCA backends.) 207- Fix some missing edge cases in CUDA backend. 208 209### Performance Improvements 210 211- MAGMA backend performance optimization and non-tensor bases. 212- No-copy optimization in {c:func}`CeedOperatorApply`. 213 214### Interface changes 215 216- Replace {code}`CeedElemRestrictionCreateIdentity` and 217 {code}`CeedElemRestrictionCreateBlocked` with more flexible 218 {c:func}`CeedElemRestrictionCreateStrided` and 219 {c:func}`CeedElemRestrictionCreateBlockedStrided`. 220- Add arguments to {c:func}`CeedQFunctionCreateIdentity`. 221- Replace ambiguous uses of {cpp:enum}`CeedTransposeMode` for L-vector identification 222 with {cpp:enum}`CeedInterlaceMode`. This is now an attribute of the 223 {cpp:type}`CeedElemRestriction` (see {c:func}`CeedElemRestrictionCreate`) and no 224 longer passed as `lmode` arguments to {c:func}`CeedOperatorSetField` and 225 {c:func}`CeedElemRestrictionApply`. 226 227### Examples 228 229libCEED-0.6 contains greatly expanded examples with {ref}`new documentation <Examples>`. 230Notable additions include: 231 232- Standalone {ref}`ex2-surface` ({file}`examples/ceed/ex2-surface`): compute the area of 233 a domain in 1, 2, and 3 dimensions by applying a Laplacian. 234 235- PETSc {ref}`example-petsc-area` ({file}`examples/petsc/area.c`): computes surface area 236 of domains (like the cube and sphere) by direct integration on a surface mesh; 237 demonstrates geometric dimension different from topological dimension. 238 239- PETSc {ref}`example-petsc-bps`: 240 241 - {file}`examples/petsc/bpsraw.c` (formerly `bps.c`): transparent CUDA support. 242 - {file}`examples/petsc/bps.c` (formerly `bpsdmplex.c`): performance improvements 243 and transparent CUDA support. 244 - {ref}`example-petsc-bps-sphere` ({file}`examples/petsc/bpssphere.c`): 245 generalizations of all CEED BPs to the surface of the sphere; demonstrates geometric 246 dimension different from topological dimension. 247 248- {ref}`example-petsc-multigrid` ({file}`examples/petsc/multigrid.c`): new p-multigrid 249 solver with algebraic multigrid coarse solve. 250 251- {ref}`example-petsc-navier-stokes` ({file}`examples/fluids/navierstokes.c`; formerly 252 `examples/navier-stokes`): unstructured grid support (using PETSc's `DMPlex`), 253 implicit time integration, SU/SUPG stabilization, free-slip boundary conditions, and 254 quasi-2D computational domain support. 255 256- {ref}`example-petsc-elasticity` ({file}`examples/solids/elasticity.c`): new solver for 257 linear elasticity, small-strain hyperelasticity, and globalized finite-strain 258 hyperelasticity using p-multigrid with algebraic multigrid coarse solve. 259 260(v0-5)= 261 262## v0.5 (Sep 18, 2019) 263 264For this release, several improvements were made. Two new CUDA backends were added to 265the family of backends, of which, the new `cuda-gen` backend achieves state-of-the-art 266performance using single-source {ref}`CeedQFunction`. From this release, users 267can define Q-Functions in a single source code independently of the targeted backend 268with the aid of a new macro `CEED QFUNCTION` to support JIT (Just-In-Time) and CPU 269compilation of the user provided {ref}`CeedQFunction` code. To allow a unified 270declaration, the {ref}`CeedQFunction` API has undergone a slight change: 271the `QFunctionField` parameter `ncomp` has been changed to `size`. This change 272requires setting the previous value of `ncomp` to `ncomp*dim` when adding a 273`QFunctionField` with eval mode `CEED EVAL GRAD`. 274 275Additionally, new CPU backends 276were included in this release, such as the `/cpu/self/opt/*` backends (which are 277written in pure C and use partial **E-vectors** to improve performance) and the 278`/cpu/self/ref/memcheck` backend (which relies upon the 279[Valgrind](http://valgrind.org/) Memcheck tool to help verify that user 280{ref}`CeedQFunction` have no undefined values). 281This release also included various performance improvements, bug fixes, new examples, 282and improved tests. Among these improvements, vectorized instructions for 283{ref}`CeedQFunction` code compiled for CPU were enhanced by using `CeedPragmaSIMD` 284instead of `CeedPragmaOMP`, implementation of a {ref}`CeedQFunction` gallery and 285identity Q-Functions were introduced, and the PETSc benchmark problems were expanded 286to include unstructured meshes handling were. For this expansion, the prior version of 287the PETSc BPs, which only included data associated with structured geometries, were 288renamed `bpsraw`, and the new version of the BPs, which can handle data associated 289with any unstructured geometry, were called `bps`. Additionally, other benchmark 290problems, namely BP2 and BP4 (the vector-valued versions of BP1 and BP3, respectively), 291and BP5 and BP6 (the collocated versions---for which the quadrature points are the same 292as the Gauss Lobatto nodes---of BP3 and BP4 respectively) were added to the PETSc 293examples. Furthermoew, another standalone libCEED example, called `ex2`, which 294computes the surface area of a given mesh was added to this release. 295 296Backends available in this release: 297 298| CEED resource (`-ceed`) | Backend | 299|--------------------------|-----------------------------------------------------| 300| `/cpu/self/ref/serial` | Serial reference implementation | 301| `/cpu/self/ref/blocked` | Blocked reference implementation | 302| `/cpu/self/ref/memcheck` | Memcheck backend, undefined value checks | 303| `/cpu/self/opt/serial` | Serial optimized C implementation | 304| `/cpu/self/opt/blocked` | Blocked optimized C implementation | 305| `/cpu/self/avx/serial` | Serial AVX implementation | 306| `/cpu/self/avx/blocked` | Blocked AVX implementation | 307| `/cpu/self/xsmm/serial` | Serial LIBXSMM implementation | 308| `/cpu/self/xsmm/blocked` | Blocked LIBXSMM implementation | 309| `/cpu/occa` | Serial OCCA kernels | 310| `/gpu/occa` | CUDA OCCA kernels | 311| `/omp/occa` | OpenMP OCCA kernels | 312| `/ocl/occa` | OpenCL OCCA kernels | 313| `/gpu/cuda/ref` | Reference pure CUDA kernels | 314| `/gpu/cuda/reg` | Pure CUDA kernels using one thread per element | 315| `/gpu/cuda/shared` | Optimized pure CUDA kernels using shared memory | 316| `/gpu/cuda/gen` | Optimized pure CUDA kernels using code generation | 317| `/gpu/magma` | CUDA MAGMA kernels | 318 319Examples available in this release: 320 321:::{list-table} 322:header-rows: 1 323:widths: auto 324* - User code 325 - Example 326* - `ceed` 327 - * ex1 (volume) 328 * ex2 (surface) 329* - `mfem` 330 - * BP1 (scalar mass operator) 331 * BP3 (scalar Laplace operator) 332* - `petsc` 333 - * BP1 (scalar mass operator) 334 * BP2 (vector mass operator) 335 * BP3 (scalar Laplace operator) 336 * BP4 (vector Laplace operator) 337 * BP5 (collocated scalar Laplace operator) 338 * BP6 (collocated vector Laplace operator) 339 * Navier-Stokes 340* - `nek5000` 341 - * BP1 (scalar mass operator) 342 * BP3 (scalar Laplace operator) 343::: 344 345(v0-4)= 346 347## v0.4 (Apr 1, 2019) 348 349libCEED v0.4 was made again publicly available in the second full CEED software 350distribution, release CEED 2.0. This release contained notable features, such as 351four new CPU backends, two new GPU backends, CPU backend optimizations, initial 352support for operator composition, performance benchmarking, and a Navier-Stokes demo. 353The new CPU backends in this release came in two families. The `/cpu/self/*/serial` 354backends process one element at a time and are intended for meshes with a smaller number 355of high order elements. The `/cpu/self/*/blocked` backends process blocked batches of 356eight interlaced elements and are intended for meshes with higher numbers of elements. 357The `/cpu/self/avx/*` backends rely upon AVX instructions to provide vectorized CPU 358performance. The `/cpu/self/xsmm/*` backends rely upon the 359[LIBXSMM](http://github.com/hfp/libxsmm) package to provide vectorized CPU 360performance. The `/gpu/cuda/*` backends provide GPU performance strictly using CUDA. 361The `/gpu/cuda/ref` backend is a reference CUDA backend, providing reasonable 362performance for most problem configurations. The `/gpu/cuda/reg` backend uses a simple 363parallelization approach, where each thread treats a finite element. Using just in time 364compilation, provided by nvrtc (NVidia Runtime Compiler), and runtime parameters, this 365backend unroll loops and map memory address to registers. The `/gpu/cuda/reg` backend 366achieve good peak performance for 1D, 2D, and low order 3D problems, but performance 367deteriorates very quickly when threads run out of registers. 368 369A new explicit time-stepping Navier-Stokes solver was added to the family of libCEED 370examples in the `examples/petsc` directory (see {ref}`example-petsc-navier-stokes`). 371This example solves the time-dependent Navier-Stokes equations of compressible gas 372dynamics in a static Eulerian three-dimensional frame, using structured high-order 373finite/spectral element spatial discretizations and explicit high-order time-stepping 374(available in PETSc). Moreover, the Navier-Stokes example was developed using PETSc, 375so that the pointwise physics (defined at quadrature points) is separated from the 376parallelization and meshing concerns. 377 378Backends available in this release: 379 380| CEED resource (`-ceed`) | Backend | 381|--------------------------|-----------------------------------------------------| 382| `/cpu/self/ref/serial` | Serial reference implementation | 383| `/cpu/self/ref/blocked` | Blocked reference implementation | 384| `/cpu/self/tmpl` | Backend template, defaults to `/cpu/self/blocked` | 385| `/cpu/self/avx/serial` | Serial AVX implementation | 386| `/cpu/self/avx/blocked` | Blocked AVX implementation | 387| `/cpu/self/xsmm/serial` | Serial LIBXSMM implementation | 388| `/cpu/self/xsmm/blocked` | Blocked LIBXSMM implementation | 389| `/cpu/occa` | Serial OCCA kernels | 390| `/gpu/occa` | CUDA OCCA kernels | 391| `/omp/occa` | OpenMP OCCA kernels | 392| `/ocl/occa` | OpenCL OCCA kernels | 393| `/gpu/cuda/ref` | Reference pure CUDA kernels | 394| `/gpu/cuda/reg` | Pure CUDA kernels using one thread per element | 395| `/gpu/magma` | CUDA MAGMA kernels | 396 397Examples available in this release: 398 399:::{list-table} 400:header-rows: 1 401:widths: auto 402* - User code 403 - Example 404* - `ceed` 405 - * ex1 (volume) 406* - `mfem` 407 - * BP1 (scalar mass operator) 408 * BP3 (scalar Laplace operator) 409* - `petsc` 410 - * BP1 (scalar mass operator) 411 * BP3 (scalar Laplace operator) 412 * Navier-Stokes 413* - `nek5000` 414 - * BP1 (scalar mass operator) 415 * BP3 (scalar Laplace operator) 416::: 417 418(v0-3)= 419 420## v0.3 (Sep 30, 2018) 421 422Notable features in this release include active/passive field interface, support for 423non-tensor bases, backend optimization, and improved Fortran interface. This release 424also focused on providing improved continuous integration, and many new tests with code 425coverage reports of about 90%. This release also provided a significant change to the 426public interface: a {ref}`CeedQFunction` can take any number of named input and output 427arguments while {ref}`CeedOperator` connects them to the actual data, which may be 428supplied explicitly to `CeedOperatorApply()` (active) or separately via 429`CeedOperatorSetField()` (passive). This interface change enables reusable libraries 430of CeedQFunctions and composition of block solvers constructed using 431{ref}`CeedOperator`. A concept of blocked restriction was added to this release and 432used in an optimized CPU backend. Although this is typically not visible to the user, 433it enables effective use of arbitrary-length SIMD while maintaining cache locality. 434This CPU backend also implements an algebraic factorization of tensor product gradients 435to perform fewer operations than standard application of interpolation and 436differentiation from nodes to quadrature points. This algebraic formulation 437automatically supports non-polynomial and non-interpolatory bases, thus is more general 438than the more common derivation in terms of Lagrange polynomials on the quadrature points. 439 440Backends available in this release: 441 442| CEED resource (`-ceed`) | Backend | 443|-------------------------|-----------------------------------------------------| 444| `/cpu/self/blocked` | Blocked reference implementation | 445| `/cpu/self/ref` | Serial reference implementation | 446| `/cpu/self/tmpl` | Backend template, defaults to `/cpu/self/blocked` | 447| `/cpu/occa` | Serial OCCA kernels | 448| `/gpu/occa` | CUDA OCCA kernels | 449| `/omp/occa` | OpenMP OCCA kernels | 450| `/ocl/occa` | OpenCL OCCA kernels | 451| `/gpu/magma` | CUDA MAGMA kernels | 452 453Examples available in this release: 454 455:::{list-table} 456:header-rows: 1 457:widths: auto 458* - User code 459 - Example 460* - `ceed` 461 - * ex1 (volume) 462* - `mfem` 463 - * BP1 (scalar mass operator) 464 * BP3 (scalar Laplace operator) 465* - `petsc` 466 - * BP1 (scalar mass operator) 467 * BP3 (scalar Laplace operator) 468* - `nek5000` 469 - * BP1 (scalar mass operator) 470 * BP3 (scalar Laplace operator) 471::: 472 473(v0-21)= 474 475## v0.21 (Sep 30, 2018) 476 477A MAGMA backend (which relies upon the 478[MAGMA](https://bitbucket.org/icl/magma) package) was integrated in libCEED for this 479release. This initial integration set up the framework of using MAGMA and provided the 480libCEED functionality through MAGMA kernels as one of libCEED’s computational backends. 481As any other backend, the MAGMA backend provides extended basic data structures for 482{ref}`CeedVector`, {ref}`CeedElemRestriction`, and {ref}`CeedOperator`, and implements 483the fundamental CEED building blocks to work with the new data structures. 484In general, the MAGMA-specific data structures keep the libCEED pointers to CPU data 485but also add corresponding device (e.g., GPU) pointers to the data. Coherency is handled 486internally, and thus seamlessly to the user, through the functions/methods that are 487provided to support them. 488 489Backends available in this release: 490 491| CEED resource (`-ceed`) | Backend | 492|-------------------------|---------------------------------| 493| `/cpu/self` | Serial reference implementation | 494| `/cpu/occa` | Serial OCCA kernels | 495| `/gpu/occa` | CUDA OCCA kernels | 496| `/omp/occa` | OpenMP OCCA kernels | 497| `/ocl/occa` | OpenCL OCCA kernels | 498| `/gpu/magma` | CUDA MAGMA kernels | 499 500Examples available in this release: 501 502:::{list-table} 503:header-rows: 1 504:widths: auto 505* - User code 506 - Example 507* - `ceed` 508 - * ex1 (volume) 509* - `mfem` 510 - * BP1 (scalar mass operator) 511 * BP3 (scalar Laplace operator) 512* - `petsc` 513 - * BP1 (scalar mass operator) 514* - `nek5000` 515 - * BP1 (scalar mass operator) 516::: 517 518(v0-2)= 519 520## v0.2 (Mar 30, 2018) 521 522libCEED was made publicly available the first full CEED software distribution, release 523CEED 1.0. The distribution was made available using the Spack package manager to provide 524a common, easy-to-use build environment, where the user can build the CEED distribution 525with all dependencies. This release included a new Fortran interface for the library. 526This release also contained major improvements in the OCCA backend (including a new 527`/ocl/occa` backend) and new examples. The standalone libCEED example was modified to 528compute the volume volume of a given mesh (in 1D, 2D, or 3D) and placed in an 529`examples/ceed` subfolder. A new `mfem` example to perform BP3 (with the application 530of the Laplace operator) was also added to this release. 531 532Backends available in this release: 533 534| CEED resource (`-ceed`) | Backend | 535|-------------------------|---------------------------------| 536| `/cpu/self` | Serial reference implementation | 537| `/cpu/occa` | Serial OCCA kernels | 538| `/gpu/occa` | CUDA OCCA kernels | 539| `/omp/occa` | OpenMP OCCA kernels | 540| `/ocl/occa` | OpenCL OCCA kernels | 541 542Examples available in this release: 543 544:::{list-table} 545:header-rows: 1 546:widths: auto 547* - User code 548 - Example 549* - `ceed` 550 - * ex1 (volume) 551* - `mfem` 552 - * BP1 (scalar mass operator) 553 * BP3 (scalar Laplace operator) 554* - `petsc` 555 - * BP1 (scalar mass operator) 556* - `nek5000` 557 - * BP1 (scalar mass operator) 558::: 559 560(v0-1)= 561 562## v0.1 (Jan 3, 2018) 563 564Initial low-level API of the CEED project. The low-level API provides a set of Finite 565Elements kernels and components for writing new low-level kernels. Examples include: 566vector and sparse linear algebra, element matrix assembly over a batch of elements, 567partial assembly and action for efficient high-order operators like mass, diffusion, 568advection, etc. The main goal of the low-level API is to establish the basis for the 569high-level API. Also, identifying such low-level kernels and providing a reference 570implementation for them serves as the basis for specialized backend implementations. 571This release contained several backends: `/cpu/self`, and backends which rely upon the 572[OCCA](http://github.com/libocca/occa) package, such as `/cpu/occa`, 573`/gpu/occa`, and `/omp/occa`. 574It also included several examples, in the `examples` folder: 575A standalone code that shows the usage of libCEED (with no external 576dependencies) to apply the Laplace operator, `ex1`; an `mfem` example to perform BP1 577(with the application of the mass operator); and a `petsc` example to perform BP1 578(with the application of the mass operator). 579 580Backends available in this release: 581 582| CEED resource (`-ceed`) | Backend | 583|-------------------------|---------------------------------| 584| `/cpu/self` | Serial reference implementation | 585| `/cpu/occa` | Serial OCCA kernels | 586| `/gpu/occa` | CUDA OCCA kernels | 587| `/omp/occa` | OpenMP OCCA kernels | 588 589Examples available in this release: 590 591| User code | Example | 592|-----------------------|-----------------------------------| 593| `ceed` | ex1 (scalar Laplace operator) | 594| `mfem` | BP1 (scalar mass operator) | 595| `petsc` | BP1 (scalar mass operator) | 596``` 597