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### Interface changes 10 11- Added {c:func}`CeedOperatorSetName` for more readable {c:func}`CeedOperatorView` output. 12- Added {c:func}`CeedBasisCreateProjection` to facilitate interpolation between nodes for separate `CeedBases`. 13 14### New features 15 16- Update `/cpu/self/memcheck/*` backends to help verify `CeedQFunctionContext` data sizes provided by user. 17 18### Bugfix 19 20- Fix bug in setting device id for GPU backends. 21- Fix storing of indices for `CeedElemRestriction` on the host with GPU backends. 22- Fix `CeedElemRestriction` sizing for {c:func}`CeedOperatorAssemblePointBlockDiagonal`. 23- Fix bugs in CPU implementation of {c:func}`CeedOperatorLinearAssemble` when there are different number of active input modes and active output modes. 24 25### Examples 26 27- Added various performance enhancements for {ref}`example-petsc-navier-stokes`. 28- Refactored {ref}`example-petsc-navier-stokes` to improve code reuse. 29- Added Shock Tube, Channel, and Flat Plate boundary layer problems to {ref}`example-petsc-navier-stokes`. 30 31(v0-10-1)= 32 33## v0.10.1 (Apr 11, 2022) 34 35### Interface changes 36 37- Added {c:func}`CeedQFunctionSetUserFlopsEstimate` and {c:func}`CeedOperatorGetFlopsEstimate` to facilitate estimating FLOPs in operator application. 38 39### New features 40 41- Switched MAGMA backends to use runtime compilation for tensor basis kernels (and element restriction kernels, in non-deterministic `/gpu/*/magma` backends). 42This reduces time to compile the library and increases the range of parameters for which the MAGMA tensor basis kernels will work. 43 44### Bugfix 45 46- Install JiT source files in install directory to fix GPU functionality for installed libCEED. 47 48(v0-10)= 49 50## v0.10 (Mar 21, 2022) 51 52### Interface changes 53 54- Update {c:func}`CeedQFunctionGetFields` and {c:func}`CeedOperatorGetFields` to include number of fields. 55- 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`. 56- Clarify and document conditions where `CeedQFunction` and `CeedOperator` become immutable and no further fields or suboperators can be added. 57- Add {c:func}`CeedOperatorLinearAssembleQFunctionBuildOrUpdate` to reduce object creation overhead in assembly of CeedOperator preconditioning ingredients. 58- Promote {c:func}`CeedOperatorCheckReady`to the public API to facilitate interactive interfaces. 59- Warning added when compiling OCCA backend to alert users that this backend is experimental. 60- `ceed-backend.h`, `ceed-hash.h`, and `ceed-khash.h` removed. Users should use `ceed/backend.h`, `ceed/hash.h`, and `ceed/khash.h`. 61- Added {c:func}`CeedQFunctionGetKernelName`; refactored {c:func}`CeedQFunctionGetSourcePath` to exclude function kernel name. 62- 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`. 63- Added {c:func}`CeedVectorGetArrayWrite` that allows access to uninitalized arrays; require initalized data for {c:func}`CeedVectorGetArray`. 64- 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. 65- Added {c:func}`CeedQFunctionContextGetFieldDescriptions` to retreive user defined descriptions of fields that are registered with `CeedQFunctionContextRegister*`. 66- Renamed `CeedElemTopology` entries for clearer namespacing between libCEED enums. 67- 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. 68- Added {c:func}`CeedOperatorSetQFunctionUpdated` to facilitate QFunction data re-use between operators sharing the same quadrature space, such as in a multigrid hierarchy. 69- Added {c:func}`CeedOperatorGetActiveVectorLengths` to get shape of CeedOperator. 70 71### New features 72 73- `CeedScalar` can now be set as `float` or `double` at compile time. 74- Added JiT utilities in `ceed/jit-tools.h` to reduce duplicated code in GPU backends. 75- 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. 76- Remove need to guard library headers in QFunction source for code generation backends. 77- `CeedDebugEnv()` macro created to provide debugging outputs when Ceed context is not present. 78- Added {c:func}`CeedStringAllocCopy` to reduce repeated code for copying strings internally. 79- Added {c:func}`CeedPathConcatenate` to facilitate loading kernel source files with a path relative to the current file. 80- Added support for non-tensor H(div) elements, to include CPU backend implementations and {c:func}`CeedBasisCreateHdiv` convenience constructor. 81- 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. 82- Added support for element matrix assembly in GPU backends. 83 84### Maintainability 85 86- Refactored preconditioner support internally to facilitate future development and improve GPU completeness/test coverage. 87- `Include-what-you-use` makefile target added as `make iwyu`. 88- Create backend constant `CEED_FIELD_MAX` to reduce magic numbers in codebase. 89- Put GPU JiTed kernel source code into separate files. 90- 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. 91 92(v0-9)= 93 94## v0.9 (Jul 6, 2021) 95 96### Interface changes 97 98- Minor modification in error handling macro to silence pedantic warnings when compiling with Clang, but no functional impact. 99 100### New features 101 102- Add {c:func}`CeedVectorAXPY` and {c:func}`CeedVectorPointwiseMult` as a convenience for stand-alone testing and internal use. 103- Add `CEED_QFUNCTION_HELPER` macro to properly annotate QFunction helper functions for code generation backends. 104- Add `CeedPragmaOptimizeOff` macro for code that is sensitive to floating point errors from fast math optimizations. 105- Rust support: split `libceed-sys` crate out of `libceed` and [publish both on crates.io](https://crates.io/crates/libceed). 106 107### Performance improvements 108 109### Examples 110 111- Solid mechanics mini-app updated to explore the performance impacts of various formulations in the initial and current configurations. 112- Fluid mechanics example adds GPU support and improves modularity. 113 114### Deprecated backends 115 116- 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. 117 118(v0-8)= 119 120## v0.8 (Mar 31, 2021) 121 122### Interface changes 123 124- Error handling improved to include enumerated error codes for C interface return values. 125- 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. 126 127### New features 128 129- Julia and Rust interfaces added, providing a nearly 1-1 correspondence with the C interface, plus some convenience features. 130- Static libraries can be built with `make STATIC=1` and the pkg-config file is installed accordingly. 131- Add {c:func}`CeedOperatorLinearAssembleSymbolic` and {c:func}`CeedOperatorLinearAssemble` to support full assembly of libCEED operators. 132 133### Performance improvements 134 135- New HIP MAGMA backends for hipMAGMA library users: `/gpu/hip/magma` and `/gpu/hip/magma/det`. 136- New HIP backends for improved tensor basis performance: `/gpu/hip/shared` and `/gpu/hip/gen`. 137 138### Examples 139 140- {ref}`example-petsc-elasticity` example updated with traction boundary conditions and improved Dirichlet boundary conditions. 141- {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. 142- {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. 143- {ref}`example-petsc-navier-stokes` example updated with support for performing convergence study and plotting order of convergence by polynomial degree. 144 145(v0-7)= 146 147## v0.7 (Sep 29, 2020) 148 149### Interface changes 150 151- Replace limited {code}`CeedInterlaceMode` with more flexible component stride {code}`compstride` in {code}`CeedElemRestriction` constructors. 152 As a result, the {code}`indices` parameter has been replaced with {code}`offsets` and the {code}`nnodes` parameter has been replaced with {code}`lsize`. 153 These changes improve support for mixed finite element methods. 154- Replace various uses of {code}`Ceed*Get*Status` with {code}`Ceed*Is*` in the backend API to match common nomenclature. 155- Replace {code}`CeedOperatorAssembleLinearDiagonal` with {c:func}`CeedOperatorLinearAssembleDiagonal` for clarity. 156- 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. 157- 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. 158- 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. 159- 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. 160 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`. 161- Added {code}`CeedQFunctionContext` object to manage user QFunction context data and reduce copies between device and host memory. 162- 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. 163 164### New features 165 166- New HIP backend: `/gpu/hip/ref`. 167- CeedQFunction support for user `CUfunction`s in some backends 168 169### Performance improvements 170 171- OCCA backend rebuilt to facilitate future performance enhancements. 172- Petsc BPs suite improved to reduce noise due to multiple calls to {code}`mpiexec`. 173 174### Examples 175 176- {ref}`example-petsc-elasticity` example updated with strain energy computation and more flexible boundary conditions. 177 178### Deprecated backends 179 180- The `/gpu/cuda/reg` backend has been removed, with its core features moved into `/gpu/cuda/ref` and `/gpu/cuda/shared`. 181 182(v0-6)= 183 184## v0.6 (Mar 29, 2020) 185 186libCEED v0.6 contains numerous new features and examples, as well as expanded 187documentation in [this new website](https://libceed.org). 188 189### New features 190 191- New Python interface using [CFFI](https://cffi.readthedocs.io/) provides a nearly 192 1-1 correspondence with the C interface, plus some convenience features. For instance, 193 data stored in the {cpp:type}`CeedVector` structure are available without copy as 194 {py:class}`numpy.ndarray`. Short tutorials are provided in 195 [Binder](https://mybinder.org/v2/gh/CEED/libCEED/main?urlpath=lab/tree/examples/tutorials/). 196- Linear QFunctions can be assembled as block-diagonal matrices (per quadrature point, 197 {c:func}`CeedOperatorAssembleLinearQFunction`) or to evaluate the diagonal 198 ({c:func}`CeedOperatorAssembleLinearDiagonal`). These operations are useful for 199 preconditioning ingredients and are used in the libCEED's multigrid examples. 200- The inverse of separable operators can be obtained using 201 {c:func}`CeedOperatorCreateFDMElementInverse` and applied with 202 {c:func}`CeedOperatorApply`. This is a useful preconditioning ingredient, 203 especially for Laplacians and related operators. 204- New functions: {c:func}`CeedVectorNorm`, {c:func}`CeedOperatorApplyAdd`, 205 {c:func}`CeedQFunctionView`, {c:func}`CeedOperatorView`. 206- Make public accessors for various attributes to facilitate writing composable code. 207- New backend: `/cpu/self/memcheck/serial`. 208- QFunctions using variable-length array (VLA) pointer constructs can be used with CUDA 209 backends. (Single source is coming soon for OCCA backends.) 210- Fix some missing edge cases in CUDA backend. 211 212### Performance Improvements 213 214- MAGMA backend performance optimization and non-tensor bases. 215- No-copy optimization in {c:func}`CeedOperatorApply`. 216 217### Interface changes 218 219- Replace {code}`CeedElemRestrictionCreateIdentity` and 220 {code}`CeedElemRestrictionCreateBlocked` with more flexible 221 {c:func}`CeedElemRestrictionCreateStrided` and 222 {c:func}`CeedElemRestrictionCreateBlockedStrided`. 223- Add arguments to {c:func}`CeedQFunctionCreateIdentity`. 224- Replace ambiguous uses of {cpp:enum}`CeedTransposeMode` for L-vector identification 225 with {cpp:enum}`CeedInterlaceMode`. This is now an attribute of the 226 {cpp:type}`CeedElemRestriction` (see {c:func}`CeedElemRestrictionCreate`) and no 227 longer passed as `lmode` arguments to {c:func}`CeedOperatorSetField` and 228 {c:func}`CeedElemRestrictionApply`. 229 230### Examples 231 232libCEED-0.6 contains greatly expanded examples with {ref}`new documentation <Examples>`. 233Notable additions include: 234 235- Standalone {ref}`ex2-surface` ({file}`examples/ceed/ex2-surface`): compute the area of 236 a domain in 1, 2, and 3 dimensions by applying a Laplacian. 237 238- PETSc {ref}`example-petsc-area` ({file}`examples/petsc/area.c`): computes surface area 239 of domains (like the cube and sphere) by direct integration on a surface mesh; 240 demonstrates geometric dimension different from topological dimension. 241 242- PETSc {ref}`example-petsc-bps`: 243 244 - {file}`examples/petsc/bpsraw.c` (formerly `bps.c`): transparent CUDA support. 245 - {file}`examples/petsc/bps.c` (formerly `bpsdmplex.c`): performance improvements 246 and transparent CUDA support. 247 - {ref}`example-petsc-bps-sphere` ({file}`examples/petsc/bpssphere.c`): 248 generalizations of all CEED BPs to the surface of the sphere; demonstrates geometric 249 dimension different from topological dimension. 250 251- {ref}`example-petsc-multigrid` ({file}`examples/petsc/multigrid.c`): new p-multigrid 252 solver with algebraic multigrid coarse solve. 253 254- {ref}`example-petsc-navier-stokes` ({file}`examples/fluids/navierstokes.c`; formerly 255 `examples/navier-stokes`): unstructured grid support (using PETSc's `DMPlex`), 256 implicit time integration, SU/SUPG stabilization, free-slip boundary conditions, and 257 quasi-2D computational domain support. 258 259- {ref}`example-petsc-elasticity` ({file}`examples/solids/elasticity.c`): new solver for 260 linear elasticity, small-strain hyperelasticity, and globalized finite-strain 261 hyperelasticity using p-multigrid with algebraic multigrid coarse solve. 262 263(v0-5)= 264 265## v0.5 (Sep 18, 2019) 266 267For this release, several improvements were made. Two new CUDA backends were added to 268the family of backends, of which, the new `cuda-gen` backend achieves state-of-the-art 269performance using single-source {ref}`CeedQFunction`. From this release, users 270can define Q-Functions in a single source code independently of the targeted backend 271with the aid of a new macro `CEED QFUNCTION` to support JIT (Just-In-Time) and CPU 272compilation of the user provided {ref}`CeedQFunction` code. To allow a unified 273declaration, the {ref}`CeedQFunction` API has undergone a slight change: 274the `QFunctionField` parameter `ncomp` has been changed to `size`. This change 275requires setting the previous value of `ncomp` to `ncomp*dim` when adding a 276`QFunctionField` with eval mode `CEED EVAL GRAD`. 277 278Additionally, new CPU backends 279were included in this release, such as the `/cpu/self/opt/*` backends (which are 280written in pure C and use partial **E-vectors** to improve performance) and the 281`/cpu/self/ref/memcheck` backend (which relies upon the 282[Valgrind](http://valgrind.org/) Memcheck tool to help verify that user 283{ref}`CeedQFunction` have no undefined values). 284This release also included various performance improvements, bug fixes, new examples, 285and improved tests. Among these improvements, vectorized instructions for 286{ref}`CeedQFunction` code compiled for CPU were enhanced by using `CeedPragmaSIMD` 287instead of `CeedPragmaOMP`, implementation of a {ref}`CeedQFunction` gallery and 288identity Q-Functions were introduced, and the PETSc benchmark problems were expanded 289to include unstructured meshes handling were. For this expansion, the prior version of 290the PETSc BPs, which only included data associated with structured geometries, were 291renamed `bpsraw`, and the new version of the BPs, which can handle data associated 292with any unstructured geometry, were called `bps`. Additionally, other benchmark 293problems, namely BP2 and BP4 (the vector-valued versions of BP1 and BP3, respectively), 294and BP5 and BP6 (the collocated versions---for which the quadrature points are the same 295as the Gauss Lobatto nodes---of BP3 and BP4 respectively) were added to the PETSc 296examples. Furthermoew, another standalone libCEED example, called `ex2`, which 297computes the surface area of a given mesh was added to this release. 298 299Backends available in this release: 300 301| CEED resource (`-ceed`) | Backend | 302|--------------------------|-----------------------------------------------------| 303| `/cpu/self/ref/serial` | Serial reference implementation | 304| `/cpu/self/ref/blocked` | Blocked reference implementation | 305| `/cpu/self/ref/memcheck` | Memcheck backend, undefined value checks | 306| `/cpu/self/opt/serial` | Serial optimized C implementation | 307| `/cpu/self/opt/blocked` | Blocked optimized C implementation | 308| `/cpu/self/avx/serial` | Serial AVX implementation | 309| `/cpu/self/avx/blocked` | Blocked AVX implementation | 310| `/cpu/self/xsmm/serial` | Serial LIBXSMM implementation | 311| `/cpu/self/xsmm/blocked` | Blocked LIBXSMM implementation | 312| `/cpu/occa` | Serial OCCA kernels | 313| `/gpu/occa` | CUDA OCCA kernels | 314| `/omp/occa` | OpenMP OCCA kernels | 315| `/ocl/occa` | OpenCL OCCA kernels | 316| `/gpu/cuda/ref` | Reference pure CUDA kernels | 317| `/gpu/cuda/reg` | Pure CUDA kernels using one thread per element | 318| `/gpu/cuda/shared` | Optimized pure CUDA kernels using shared memory | 319| `/gpu/cuda/gen` | Optimized pure CUDA kernels using code generation | 320| `/gpu/magma` | CUDA MAGMA kernels | 321 322Examples available in this release: 323 324:::{list-table} 325:header-rows: 1 326:widths: auto 327* - User code 328 - Example 329* - `ceed` 330 - * ex1 (volume) 331 * ex2 (surface) 332* - `mfem` 333 - * BP1 (scalar mass operator) 334 * BP3 (scalar Laplace operator) 335* - `petsc` 336 - * BP1 (scalar mass operator) 337 * BP2 (vector mass operator) 338 * BP3 (scalar Laplace operator) 339 * BP4 (vector Laplace operator) 340 * BP5 (collocated scalar Laplace operator) 341 * BP6 (collocated vector Laplace operator) 342 * Navier-Stokes 343* - `nek5000` 344 - * BP1 (scalar mass operator) 345 * BP3 (scalar Laplace operator) 346::: 347 348(v0-4)= 349 350## v0.4 (Apr 1, 2019) 351 352libCEED v0.4 was made again publicly available in the second full CEED software 353distribution, release CEED 2.0. This release contained notable features, such as 354four new CPU backends, two new GPU backends, CPU backend optimizations, initial 355support for operator composition, performance benchmarking, and a Navier-Stokes demo. 356The new CPU backends in this release came in two families. The `/cpu/self/*/serial` 357backends process one element at a time and are intended for meshes with a smaller number 358of high order elements. The `/cpu/self/*/blocked` backends process blocked batches of 359eight interlaced elements and are intended for meshes with higher numbers of elements. 360The `/cpu/self/avx/*` backends rely upon AVX instructions to provide vectorized CPU 361performance. The `/cpu/self/xsmm/*` backends rely upon the 362[LIBXSMM](http://github.com/hfp/libxsmm) package to provide vectorized CPU 363performance. The `/gpu/cuda/*` backends provide GPU performance strictly using CUDA. 364The `/gpu/cuda/ref` backend is a reference CUDA backend, providing reasonable 365performance for most problem configurations. The `/gpu/cuda/reg` backend uses a simple 366parallelization approach, where each thread treats a finite element. Using just in time 367compilation, provided by nvrtc (NVidia Runtime Compiler), and runtime parameters, this 368backend unroll loops and map memory address to registers. The `/gpu/cuda/reg` backend 369achieve good peak performance for 1D, 2D, and low order 3D problems, but performance 370deteriorates very quickly when threads run out of registers. 371 372A new explicit time-stepping Navier-Stokes solver was added to the family of libCEED 373examples in the `examples/petsc` directory (see {ref}`example-petsc-navier-stokes`). 374This example solves the time-dependent Navier-Stokes equations of compressible gas 375dynamics in a static Eulerian three-dimensional frame, using structured high-order 376finite/spectral element spatial discretizations and explicit high-order time-stepping 377(available in PETSc). Moreover, the Navier-Stokes example was developed using PETSc, 378so that the pointwise physics (defined at quadrature points) is separated from the 379parallelization and meshing concerns. 380 381Backends available in this release: 382 383| CEED resource (`-ceed`) | Backend | 384|--------------------------|-----------------------------------------------------| 385| `/cpu/self/ref/serial` | Serial reference implementation | 386| `/cpu/self/ref/blocked` | Blocked reference implementation | 387| `/cpu/self/tmpl` | Backend template, defaults to `/cpu/self/blocked` | 388| `/cpu/self/avx/serial` | Serial AVX implementation | 389| `/cpu/self/avx/blocked` | Blocked AVX implementation | 390| `/cpu/self/xsmm/serial` | Serial LIBXSMM implementation | 391| `/cpu/self/xsmm/blocked` | Blocked LIBXSMM implementation | 392| `/cpu/occa` | Serial OCCA kernels | 393| `/gpu/occa` | CUDA OCCA kernels | 394| `/omp/occa` | OpenMP OCCA kernels | 395| `/ocl/occa` | OpenCL OCCA kernels | 396| `/gpu/cuda/ref` | Reference pure CUDA kernels | 397| `/gpu/cuda/reg` | Pure CUDA kernels using one thread per element | 398| `/gpu/magma` | CUDA MAGMA kernels | 399 400Examples available in this release: 401 402:::{list-table} 403:header-rows: 1 404:widths: auto 405* - User code 406 - Example 407* - `ceed` 408 - * ex1 (volume) 409* - `mfem` 410 - * BP1 (scalar mass operator) 411 * BP3 (scalar Laplace operator) 412* - `petsc` 413 - * BP1 (scalar mass operator) 414 * BP3 (scalar Laplace operator) 415 * Navier-Stokes 416* - `nek5000` 417 - * BP1 (scalar mass operator) 418 * BP3 (scalar Laplace operator) 419::: 420 421(v0-3)= 422 423## v0.3 (Sep 30, 2018) 424 425Notable features in this release include active/passive field interface, support for 426non-tensor bases, backend optimization, and improved Fortran interface. This release 427also focused on providing improved continuous integration, and many new tests with code 428coverage reports of about 90%. This release also provided a significant change to the 429public interface: a {ref}`CeedQFunction` can take any number of named input and output 430arguments while {ref}`CeedOperator` connects them to the actual data, which may be 431supplied explicitly to `CeedOperatorApply()` (active) or separately via 432`CeedOperatorSetField()` (passive). This interface change enables reusable libraries 433of CeedQFunctions and composition of block solvers constructed using 434{ref}`CeedOperator`. A concept of blocked restriction was added to this release and 435used in an optimized CPU backend. Although this is typically not visible to the user, 436it enables effective use of arbitrary-length SIMD while maintaining cache locality. 437This CPU backend also implements an algebraic factorization of tensor product gradients 438to perform fewer operations than standard application of interpolation and 439differentiation from nodes to quadrature points. This algebraic formulation 440automatically supports non-polynomial and non-interpolatory bases, thus is more general 441than the more common derivation in terms of Lagrange polynomials on the quadrature points. 442 443Backends available in this release: 444 445| CEED resource (`-ceed`) | Backend | 446|-------------------------|-----------------------------------------------------| 447| `/cpu/self/blocked` | Blocked reference implementation | 448| `/cpu/self/ref` | Serial reference implementation | 449| `/cpu/self/tmpl` | Backend template, defaults to `/cpu/self/blocked` | 450| `/cpu/occa` | Serial OCCA kernels | 451| `/gpu/occa` | CUDA OCCA kernels | 452| `/omp/occa` | OpenMP OCCA kernels | 453| `/ocl/occa` | OpenCL OCCA kernels | 454| `/gpu/magma` | CUDA MAGMA kernels | 455 456Examples available in this release: 457 458:::{list-table} 459:header-rows: 1 460:widths: auto 461* - User code 462 - Example 463* - `ceed` 464 - * ex1 (volume) 465* - `mfem` 466 - * BP1 (scalar mass operator) 467 * BP3 (scalar Laplace operator) 468* - `petsc` 469 - * BP1 (scalar mass operator) 470 * BP3 (scalar Laplace operator) 471* - `nek5000` 472 - * BP1 (scalar mass operator) 473 * BP3 (scalar Laplace operator) 474::: 475 476(v0-21)= 477 478## v0.21 (Sep 30, 2018) 479 480A MAGMA backend (which relies upon the 481[MAGMA](https://bitbucket.org/icl/magma) package) was integrated in libCEED for this 482release. This initial integration set up the framework of using MAGMA and provided the 483libCEED functionality through MAGMA kernels as one of libCEED’s computational backends. 484As any other backend, the MAGMA backend provides extended basic data structures for 485{ref}`CeedVector`, {ref}`CeedElemRestriction`, and {ref}`CeedOperator`, and implements 486the fundamental CEED building blocks to work with the new data structures. 487In general, the MAGMA-specific data structures keep the libCEED pointers to CPU data 488but also add corresponding device (e.g., GPU) pointers to the data. Coherency is handled 489internally, and thus seamlessly to the user, through the functions/methods that are 490provided to support them. 491 492Backends available in this release: 493 494| CEED resource (`-ceed`) | Backend | 495|-------------------------|---------------------------------| 496| `/cpu/self` | Serial reference implementation | 497| `/cpu/occa` | Serial OCCA kernels | 498| `/gpu/occa` | CUDA OCCA kernels | 499| `/omp/occa` | OpenMP OCCA kernels | 500| `/ocl/occa` | OpenCL OCCA kernels | 501| `/gpu/magma` | CUDA MAGMA kernels | 502 503Examples available in this release: 504 505:::{list-table} 506:header-rows: 1 507:widths: auto 508* - User code 509 - Example 510* - `ceed` 511 - * ex1 (volume) 512* - `mfem` 513 - * BP1 (scalar mass operator) 514 * BP3 (scalar Laplace operator) 515* - `petsc` 516 - * BP1 (scalar mass operator) 517* - `nek5000` 518 - * BP1 (scalar mass operator) 519::: 520 521(v0-2)= 522 523## v0.2 (Mar 30, 2018) 524 525libCEED was made publicly available the first full CEED software distribution, release 526CEED 1.0. The distribution was made available using the Spack package manager to provide 527a common, easy-to-use build environment, where the user can build the CEED distribution 528with all dependencies. This release included a new Fortran interface for the library. 529This release also contained major improvements in the OCCA backend (including a new 530`/ocl/occa` backend) and new examples. The standalone libCEED example was modified to 531compute the volume volume of a given mesh (in 1D, 2D, or 3D) and placed in an 532`examples/ceed` subfolder. A new `mfem` example to perform BP3 (with the application 533of the Laplace operator) was also added to this release. 534 535Backends available in this release: 536 537| CEED resource (`-ceed`) | Backend | 538|-------------------------|---------------------------------| 539| `/cpu/self` | Serial reference implementation | 540| `/cpu/occa` | Serial OCCA kernels | 541| `/gpu/occa` | CUDA OCCA kernels | 542| `/omp/occa` | OpenMP OCCA kernels | 543| `/ocl/occa` | OpenCL OCCA kernels | 544 545Examples available in this release: 546 547:::{list-table} 548:header-rows: 1 549:widths: auto 550* - User code 551 - Example 552* - `ceed` 553 - * ex1 (volume) 554* - `mfem` 555 - * BP1 (scalar mass operator) 556 * BP3 (scalar Laplace operator) 557* - `petsc` 558 - * BP1 (scalar mass operator) 559* - `nek5000` 560 - * BP1 (scalar mass operator) 561::: 562 563(v0-1)= 564 565## v0.1 (Jan 3, 2018) 566 567Initial low-level API of the CEED project. The low-level API provides a set of Finite 568Elements kernels and components for writing new low-level kernels. Examples include: 569vector and sparse linear algebra, element matrix assembly over a batch of elements, 570partial assembly and action for efficient high-order operators like mass, diffusion, 571advection, etc. The main goal of the low-level API is to establish the basis for the 572high-level API. Also, identifying such low-level kernels and providing a reference 573implementation for them serves as the basis for specialized backend implementations. 574This release contained several backends: `/cpu/self`, and backends which rely upon the 575[OCCA](http://github.com/libocca/occa) package, such as `/cpu/occa`, 576`/gpu/occa`, and `/omp/occa`. 577It also included several examples, in the `examples` folder: 578A standalone code that shows the usage of libCEED (with no external 579dependencies) to apply the Laplace operator, `ex1`; an `mfem` example to perform BP1 580(with the application of the mass operator); and a `petsc` example to perform BP1 581(with the application of the mass operator). 582 583Backends available in this release: 584 585| CEED resource (`-ceed`) | Backend | 586|-------------------------|---------------------------------| 587| `/cpu/self` | Serial reference implementation | 588| `/cpu/occa` | Serial OCCA kernels | 589| `/gpu/occa` | CUDA OCCA kernels | 590| `/omp/occa` | OpenMP OCCA kernels | 591 592Examples available in this release: 593 594| User code | Example | 595|-----------------------|-----------------------------------| 596| `ceed` | ex1 (scalar Laplace operator) | 597| `mfem` | BP1 (scalar mass operator) | 598| `petsc` | BP1 (scalar mass operator) | 599``` 600