xref: /libCEED/include/ceed.h (revision fa9eac48825b2c0339cddc576d44c186940d4520)
1 /// Copyright (c) 2017, Lawrence Livermore National Security, LLC. Produced at
2 /// the Lawrence Livermore National Laboratory. LLNL-CODE-734707. All Rights
3 /// reserved. See files LICENSE and NOTICE for details.
4 //
5 /// This file is part of CEED, a collection of benchmarks, miniapps, software
6 /// libraries and APIs for efficient high-order finite element and spectral
7 /// element discretizations for exascale applications. For more information and
8 /// source code availability see http://github.com/ceed.
9 ///
10 /// The CEED research is supported by the Exascale Computing Project 17-SC-20-SC,
11 /// a collaborative effort of two U.S. Department of Energy organizations (Office
12 /// of Science and the National Nuclear Security Administration) responsible for
13 /// the planning and preparation of a capable exascale ecosystem, including
14 /// software, applications, hardware, advanced system engineering and early
15 /// testbed platforms, in support of the nation's exascale computing imperative.
16 
17 /// @file
18 /// Public header for user and utility components of libCEED
19 #ifndef _ceed_h
20 #define _ceed_h
21 
22 /// @defgroup Ceed Ceed: core components
23 /// @defgroup CeedVector CeedVector: storing and manipulating vectors
24 /// @defgroup CeedElemRestriction CeedElemRestriction: restriction from local vectors to elements
25 /// @defgroup CeedBasis CeedBasis: fully discrete finite element-like objects
26 /// @defgroup CeedQFunction CeedQFunction: independent operations at quadrature points
27 /// @defgroup CeedOperator CeedOperator: composed FE-type operations on vectors
28 ///
29 /// @page FunctionCategories libCEED: Types of Functions
30 ///    libCEED provides three different header files depending upon the type of
31 ///    functions a user requires.
32 /// @section Utility Utility Functions
33 ///    These functions are intended general utilities that may be useful to
34 ///    libCEED developers and users. These functions can generally be found in
35 ///    "ceed.h".
36 /// @section Basic User Functions
37 ///    These functions are intended to be used by general users of the libCEED
38 ///    interface. These functions can generally be found in "ceed.h".
39 /// @section Advanced Backend Developer Functions
40 ///    These functions are intended to be used by backend developers of the
41 ///    libCEED interface. These functions can generally be found in
42 ///    "ceed-backend.h".
43 /// @section Developer Frontend Developer Functions
44 ///    These functions are intended to be used by frontend developers of the
45 ///    libCEED interface. These functions can generally be found in "ceed-impl.h".
46 
47 /**
48   CEED_EXTERN is used in this header to denote all publicly visible symbols.
49 
50   No other file should declare publicly visible symbols, thus it should never be
51   used outside ceed.h.
52  */
53 #ifdef __cplusplus
54 #  define CEED_EXTERN extern "C"
55 #else
56 #  define CEED_EXTERN extern
57 #endif
58 
59 #ifndef CEED_QFUNCTION
60 #define CEED_QFUNCTION(name) \
61   static const char name ## _loc[] = __FILE__ ":" #name;        \
62   static int name
63 #endif
64 
65 #ifndef CeedPragmaSIMD
66 #  if defined(__INTEL_COMPILER) &&__INTEL_COMPILER >= 900
67 #    define CeedPragmaSIMD _Pragma("simd")
68 #  elif defined(__GNUC__) && __GNUC__ >= 5
69 #    define CeedPragmaSIMD _Pragma("GCC ivdep")
70 #  elif defined(_OPENMP) && _OPENMP >= 201307 // OpenMP-4.0 (July, 2013)
71 #    define CeedPragmaSIMD _Pragma("omp simd")
72 #  else
73 #    define CeedPragmaSIMD
74 #  endif
75 #endif
76 
77 #include <assert.h>
78 #include <stdint.h>
79 #include <stddef.h>
80 #include <stdarg.h>
81 #include <stdio.h>
82 #include <stdbool.h>
83 
84 /// We can discuss ways to avoid forcing these to be compile-time decisions,
85 ///   but let's leave that for later.
86 /// Integer type, used for indexing
87 /// @ingroup Ceed
88 typedef int32_t CeedInt;
89 /// Scalar (floating point) type
90 /// @ingroup Ceed
91 typedef double CeedScalar;
92 
93 /// Library context created by CeedInit()
94 /// @ingroup Ceed
95 typedef struct Ceed_private *Ceed;
96 /// Non-blocking Ceed interfaces return a CeedRequest.
97 /// To perform an operation immediately, pass \ref CEED_REQUEST_IMMEDIATE instead.
98 /// @ingroup Ceed
99 typedef struct CeedRequest_private *CeedRequest;
100 /// Handle for vectors over the field \ref CeedScalar
101 /// @ingroup CeedVector
102 typedef struct CeedVector_private *CeedVector;
103 /// Handle for object describing restriction to elements
104 /// @ingroup CeedElemRestriction
105 typedef struct CeedElemRestriction_private *CeedElemRestriction;
106 /// Handle for object describing discrete finite element evaluations
107 /// @ingroup CeedBasis
108 typedef struct CeedBasis_private *CeedBasis;
109 /// Handle for object describing functions evaluated independently at quadrature points
110 /// @ingroup CeedQFunction
111 typedef struct CeedQFunction_private *CeedQFunction;
112 /// Handle for object describing FE-type operators acting on vectors
113 ///
114 /// Given an element restriction \f$E\f$, basis evaluator \f$B\f$, and
115 ///   quadrature function\f$f\f$, a CeedOperator expresses operations of the form
116 ///   $$ E^T B^T f(B E u) $$
117 ///   acting on the vector \f$u\f$.
118 /// @ingroup CeedOperator
119 typedef struct CeedOperator_private *CeedOperator;
120 
121 CEED_EXTERN int CeedInit(const char *resource, Ceed *ceed);
122 CEED_EXTERN int CeedGetResource(Ceed ceed, const char **resource);
123 CEED_EXTERN int CeedDestroy(Ceed *ceed);
124 
125 CEED_EXTERN int CeedErrorImpl(Ceed, const char *, int, const char *, int,
126                               const char *, ...);
127 /// Raise an error on ceed object
128 ///
129 /// @param ceed Ceed library context or NULL
130 /// @param ecode Error code (int)
131 /// @param ... printf-style format string followed by arguments as needed
132 ///
133 /// @ingroup Ceed
134 /// @sa CeedSetErrorHandler()
135 #if defined(__clang__)
136 /// Use nonstandard ternary to convince the compiler/clang-tidy that this
137 /// function never returns zero.
138 #  define CeedError(ceed, ecode, ...)                                     \
139   (CeedErrorImpl((ceed), __FILE__, __LINE__, __func__, (ecode), __VA_ARGS__) ?: (ecode))
140 #else
141 #  define CeedError(ceed, ecode, ...)                                     \
142   CeedErrorImpl((ceed), __FILE__, __LINE__, __func__, (ecode), __VA_ARGS__) ?: (ecode)
143 #endif
144 /// Specify memory type
145 ///
146 /// Many Ceed interfaces take or return pointers to memory.  This enum is used to
147 /// specify where the memory being provided or requested must reside.
148 /// @ingroup Ceed
149 typedef enum {
150   /// Memory resides on the host
151   CEED_MEM_HOST,
152   /// Memory resides on a device (corresponding to \ref Ceed resource)
153   CEED_MEM_DEVICE,
154 } CeedMemType;
155 
156 CEED_EXTERN const char *const CeedMemTypes[];
157 
158 CEED_EXTERN int CeedGetPreferredMemType(Ceed ceed, CeedMemType *type);
159 
160 /// Conveys ownership status of arrays passed to Ceed interfaces.
161 /// @ingroup Ceed
162 typedef enum {
163   /// Implementation will copy the values and not store the passed pointer.
164   CEED_COPY_VALUES,
165   /// Implementation can use and modify the data provided by the user, but does
166   /// not take ownership.
167   CEED_USE_POINTER,
168   /// Implementation takes ownership of the pointer and will free using
169   /// CeedFree() when done using it.  The user should not assume that the
170   /// pointer remains valid after ownership has been transferred.  Note that
171   /// arrays allocated using C++ operator new or other allocators cannot
172   /// generally be freed using CeedFree().  CeedFree() is capable of freeing any
173   /// memory that can be freed using free(3).
174   CEED_OWN_POINTER,
175 } CeedCopyMode;
176 
177 CEED_EXTERN const char *const CeedCopyModes[];
178 
179 CEED_EXTERN int CeedVectorCreate(Ceed ceed, CeedInt len, CeedVector *vec);
180 CEED_EXTERN int CeedVectorSetArray(CeedVector vec, CeedMemType mtype,
181                                    CeedCopyMode cmode, CeedScalar *array);
182 CEED_EXTERN int CeedVectorSetValue(CeedVector vec, CeedScalar value);
183 CEED_EXTERN int CeedVectorSyncArray(CeedVector vec, CeedMemType mtype);
184 CEED_EXTERN int CeedVectorGetArray(CeedVector vec, CeedMemType mtype,
185                                    CeedScalar **array);
186 CEED_EXTERN int CeedVectorGetArrayRead(CeedVector vec, CeedMemType mtype,
187                                        const CeedScalar **array);
188 CEED_EXTERN int CeedVectorRestoreArray(CeedVector vec, CeedScalar **array);
189 CEED_EXTERN int CeedVectorRestoreArrayRead(CeedVector vec,
190     const CeedScalar **array);
191 CEED_EXTERN int CeedVectorView(CeedVector vec, const char *fpfmt, FILE *stream);
192 CEED_EXTERN int CeedVectorGetLength(CeedVector vec, CeedInt *length);
193 CEED_EXTERN int CeedVectorDestroy(CeedVector *vec);
194 
195 CEED_EXTERN CeedRequest *const CEED_REQUEST_IMMEDIATE;
196 CEED_EXTERN CeedRequest *const CEED_REQUEST_ORDERED;
197 CEED_EXTERN int CeedRequestWait(CeedRequest *req);
198 
199 /// Argument for CeedOperatorSetField that vector is collocated with
200 /// quadrature points, used with QFunction eval mode CEED_EVAL_NONE
201 /// or CEED_EVAL_INTERP only, not with CEED_EVAL_GRAD, CEED_EVAL_DIV,
202 /// or CEED_EVAL_CURL
203 /// @ingroup CeedBasis
204 CEED_EXTERN CeedBasis CEED_BASIS_COLLOCATED;
205 
206 /// Argument for CeedOperatorSetField to use active input or output
207 /// @ingroup CeedVector
208 CEED_EXTERN CeedVector CEED_VECTOR_ACTIVE;
209 
210 /// Argument for CeedOperatorSetField to use no vector, used with
211 /// qfunction input with eval mode CEED_EVAL_WEIGHTS
212 /// @ingroup CeedVector
213 CEED_EXTERN CeedVector CEED_VECTOR_NONE;
214 
215 /// Argument for CeedOperatorCreate that QFunction is not created by user.
216 /// Only used for QFunctions dqf and dqfT. If implemented, a backend may
217 /// attempt to provide the action of these QFunctions.
218 /// @ingroup CeedQFunction
219 CEED_EXTERN CeedQFunction CEED_QFUNCTION_NONE;
220 
221 /// Denotes whether a linear transformation or its transpose should be applied
222 /// @ingroup CeedBasis
223 typedef enum {
224   /// Apply the linear transformation
225   CEED_NOTRANSPOSE,
226   /// Apply the transpose
227   CEED_TRANSPOSE
228 } CeedTransposeMode;
229 
230 CEED_EXTERN const char *const CeedTransposeModes[];
231 
232 CEED_EXTERN int CeedElemRestrictionCreate(Ceed ceed, CeedInt nelem,
233     CeedInt elemsize, CeedInt nnodes, CeedInt ncomp, CeedMemType mtype,
234     CeedCopyMode cmode,
235     const CeedInt *indices, CeedElemRestriction *rstr);
236 CEED_EXTERN int CeedElemRestrictionCreateIdentity(Ceed ceed, CeedInt nelem,
237     CeedInt elemsize, CeedInt nnodes, CeedInt ncomp, CeedElemRestriction *rstr);
238 CEED_EXTERN int CeedElemRestrictionCreateBlocked(Ceed ceed, CeedInt nelem,
239     CeedInt elemsize, CeedInt blksize, CeedInt nnodes, CeedInt ncomp,
240     CeedMemType mtype,
241     CeedCopyMode cmode, const CeedInt *indices, CeedElemRestriction *rstr);
242 CEED_EXTERN int CeedElemRestrictionCreateVector(CeedElemRestriction rstr,
243     CeedVector *lvec, CeedVector *evec);
244 CEED_EXTERN int CeedElemRestrictionApply(CeedElemRestriction rstr,
245     CeedTransposeMode tmode, CeedTransposeMode lmode, CeedVector u,
246     CeedVector ru, CeedRequest *request);
247 CEED_EXTERN int CeedElemRestrictionApplyBlock(CeedElemRestriction rstr,
248     CeedInt block, CeedTransposeMode tmode, CeedTransposeMode lmode,
249     CeedVector u, CeedVector ru, CeedRequest *request);
250 CEED_EXTERN int CeedElemRestrictionGetMultiplicity(CeedElemRestriction rstr,
251     CeedTransposeMode tmode, CeedVector mult);
252 CEED_EXTERN int CeedElemRestrictionCreateVector(CeedElemRestriction rstr,
253     CeedVector *lvec, CeedVector *evec);
254 CEED_EXTERN int CeedElemRestrictionView(CeedElemRestriction rstr, FILE *stream);
255 CEED_EXTERN int CeedElemRestrictionDestroy(CeedElemRestriction *rstr);
256 
257 /// The formalism here is that we have the structure
258 ///   \int_\Omega v^T f_0(u, \nabla u, qdata) + (\nabla v)^T f_1(u, \nabla u, qdata)
259 /// where gradients are with respect to the reference element.
260 
261 /// Basis evaluation mode
262 ///
263 /// Modes can be bitwise ORed when passing to most functions.
264 /// @ingroup CeedBasis
265 typedef enum {
266   /// Perform no evaluation (either because there is no data or it is already at
267   /// quadrature points)
268   CEED_EVAL_NONE   = 0,
269   /// Interpolate from nodes to quadrature points
270   CEED_EVAL_INTERP = 1,
271   /// Evaluate gradients at quadrature points from input in a nodal basis
272   CEED_EVAL_GRAD   = 2,
273   /// Evaluate divergence at quadrature points from input in a nodal basis
274   CEED_EVAL_DIV    = 4,
275   /// Evaluate curl at quadrature points from input in a nodal basis
276   CEED_EVAL_CURL   = 8,
277   /// Using no input, evaluate quadrature weights on the reference element
278   CEED_EVAL_WEIGHT = 16,
279 } CeedEvalMode;
280 
281 CEED_EXTERN const char *const CeedEvalModes[];
282 
283 /// Type of quadrature; also used for location of nodes
284 /// @ingroup CeedBasis
285 typedef enum {
286   /// Gauss-Legendre quadrature
287   CEED_GAUSS = 0,
288   /// Gauss-Legendre-Lobatto quadrature
289   CEED_GAUSS_LOBATTO = 1,
290 } CeedQuadMode;
291 
292 CEED_EXTERN const char *const CeedQuadModes[];
293 
294 /// Type of basis shape to create non-tensor H1 element basis
295 ///
296 /// Dimension can be extracted with bitwise AND
297 /// (CeedElemTopology & 2**(dim + 2)) == TRUE
298 /// @ingroup CeedBasis
299 typedef enum {
300   /// Line
301   CEED_LINE = 1 << 16 | 0,
302   /// Triangle - 2D shape
303   CEED_TRIANGLE = 2 << 16 | 1,
304   /// Quadralateral - 2D shape
305   CEED_QUAD = 2 << 16 | 2,
306   /// Tetrahedron - 3D shape
307   CEED_TET = 3 << 16 | 3,
308   /// Pyramid - 3D shape
309   CEED_PYRAMID = 3 << 16 | 4,
310   /// Prism - 3D shape
311   CEED_PRISM = 3 << 16 | 5,
312   /// Hexehedron - 3D shape
313   CEED_HEX = 3 << 16 | 6,
314 } CeedElemTopology;
315 
316 CEED_EXTERN const char *const CeedElemTopologies[];
317 
318 CEED_EXTERN int CeedBasisCreateTensorH1Lagrange(Ceed ceed, CeedInt dim,
319     CeedInt ncomp, CeedInt P, CeedInt Q, CeedQuadMode qmode, CeedBasis *basis);
320 CEED_EXTERN int CeedBasisCreateTensorH1(Ceed ceed, CeedInt dim, CeedInt ncomp,
321                                         CeedInt P1d, CeedInt Q1d,
322                                         const CeedScalar *interp1d,
323                                         const CeedScalar *grad1d,
324                                         const CeedScalar *qref1d,
325                                         const CeedScalar *qweight1d,
326                                         CeedBasis *basis);
327 CEED_EXTERN int CeedBasisCreateH1(Ceed ceed, CeedElemTopology topo,
328                                   CeedInt ncomp,
329                                   CeedInt nnodes, CeedInt nqpts,
330                                   const CeedScalar *interp,
331                                   const CeedScalar *grad,
332                                   const CeedScalar *qref,
333                                   const CeedScalar *qweight, CeedBasis *basis);
334 CEED_EXTERN int CeedBasisView(CeedBasis basis, FILE *stream);
335 CEED_EXTERN int CeedBasisGetNumNodes(CeedBasis basis, CeedInt *P);
336 CEED_EXTERN int CeedBasisGetNumQuadraturePoints(CeedBasis basis, CeedInt *Q);
337 CEED_EXTERN int CeedBasisApply(CeedBasis basis, CeedInt nelem,
338                                CeedTransposeMode tmode,
339                                CeedEvalMode emode, CeedVector u, CeedVector v);
340 CEED_EXTERN int CeedBasisDestroy(CeedBasis *basis);
341 
342 CEED_EXTERN int CeedGaussQuadrature(CeedInt Q, CeedScalar *qref1d,
343                                     CeedScalar *qweight1d);
344 CEED_EXTERN int CeedLobattoQuadrature(CeedInt Q, CeedScalar *qref1d,
345                                       CeedScalar *qweight1d);
346 CEED_EXTERN int CeedQRFactorization(Ceed ceed, CeedScalar *mat, CeedScalar *tau,
347                                     CeedInt m, CeedInt n);
348 CEED_EXTERN int CeedSymmetricSchurDecomposition(Ceed ceed, CeedScalar *mat,
349     CeedScalar *lambda, CeedInt n);
350 CEED_EXTERN int CeedSimultaneousDiagonalization(Ceed ceed, CeedScalar *matA,
351     CeedScalar *matB, CeedScalar *x, CeedScalar *lambda, CeedInt n);
352 
353 /** Handle for the object describing the user CeedQFunction
354 
355  @param ctx user-defined context set using CeedQFunctionSetContext() or NULL
356 
357  @param Q   number of quadrature points at which to evaluate
358 
359  @param in  array of pointers to each input argument in the order provided
360               by the user in CeedQFunctionAddInput().  Each array has shape
361               `[dim, ncomp, Q]` where `dim` is the geometric dimension for
362               \ref CEED_EVAL_GRAD (`dim=1` for \ref CEED_EVAL_INTERP) and
363               `ncomp` is the number of field components (`ncomp=1` for
364               scalar fields).  This results in indexing the `i`th input at
365               quadrature point `j` as `in[i][(d*ncomp + c)*Q + j]`.
366 
367  @param out array of pointers to each output array in the order provided
368               using CeedQFunctionAddOutput().  The shapes are as above for
369               \a in.
370 
371  @return An error code: 0 - success, otherwise - failure
372 
373  @ingroup CeedQFunction
374 **/
375 typedef int (*CeedQFunctionUser)(void *ctx, const CeedInt Q,
376                                  const CeedScalar *const *in,
377                                  CeedScalar *const *out);
378 
379 CEED_EXTERN int CeedQFunctionCreateInterior(Ceed ceed, CeedInt vlength,
380     CeedQFunctionUser f, const char *source, CeedQFunction *qf);
381 CEED_EXTERN int CeedQFunctionCreateInteriorByName(Ceed ceed, const char *name,
382     CeedQFunction *qf);
383 CEED_EXTERN int CeedQFunctionCreateIdentity(Ceed ceed, CeedInt size,
384     CeedEvalMode inmode, CeedEvalMode outmode, CeedQFunction *qf);
385 CEED_EXTERN int CeedQFunctionAddInput(CeedQFunction qf, const char *fieldname,
386                                       CeedInt size, CeedEvalMode emode);
387 CEED_EXTERN int CeedQFunctionAddOutput(CeedQFunction qf, const char *fieldname,
388                                        CeedInt size, CeedEvalMode emode);
389 CEED_EXTERN int CeedQFunctionSetContext(CeedQFunction qf, void *ctx,
390                                         size_t ctxsize);
391 CEED_EXTERN int CeedQFunctionView(CeedQFunction qf, FILE *stream);
392 CEED_EXTERN int CeedQFunctionApply(CeedQFunction qf, CeedInt Q,
393                                    CeedVector *u, CeedVector *v);
394 CEED_EXTERN int CeedQFunctionDestroy(CeedQFunction *qf);
395 
396 CEED_EXTERN int CeedOperatorCreate(Ceed ceed, CeedQFunction qf,
397                                    CeedQFunction dqf, CeedQFunction dqfT,
398                                    CeedOperator *op);
399 CEED_EXTERN int CeedCompositeOperatorCreate(Ceed ceed, CeedOperator *op);
400 CEED_EXTERN int CeedOperatorSetField(CeedOperator op, const char *fieldname,
401                                      CeedElemRestriction r,
402                                      CeedTransposeMode lmode, CeedBasis b,
403                                      CeedVector v);
404 CEED_EXTERN int CeedCompositeOperatorAddSub(CeedOperator compositeop,
405     CeedOperator subop);
406 CEED_EXTERN int CeedOperatorAssembleLinearQFunction(CeedOperator op,
407     CeedVector *assembled, CeedElemRestriction *rstr, CeedRequest *request);
408 CEED_EXTERN int CeedOperatorAssembleLinearDiagonal(CeedOperator op,
409     CeedVector *assembled, CeedRequest *request);
410 CEED_EXTERN int CeedOperatorView(CeedOperator op, FILE *stream);
411 CEED_EXTERN int CeedOperatorCreateFDMElementInverse(CeedOperator op,
412     CeedOperator *fdminv, CeedRequest *request);
413 CEED_EXTERN int CeedOperatorApply(CeedOperator op, CeedVector in,
414                                   CeedVector out, CeedRequest *request);
415 CEED_EXTERN int CeedOperatorApplyAdd(CeedOperator op, CeedVector in,
416                                      CeedVector out, CeedRequest *request);
417 CEED_EXTERN int CeedOperatorDestroy(CeedOperator *op);
418 
419 /**
420   @brief Return integer power
421 
422   @param[in] base   The base to exponentiate
423   @param[in] power  The power to raise the base to
424 
425   @return base^power
426 
427   @ref Utility
428 **/
429 static inline CeedInt CeedIntPow(CeedInt base, CeedInt power) {
430   CeedInt result = 1;
431   while (power) {
432     if (power & 1) result *= base;
433     power >>= 1;
434     base *= base;
435   }
436   return result;
437 }
438 
439 /**
440   @brief Return minimum of two integers
441 
442   @param[in] a  The first integer to compare
443   @param[in] b  The second integer to compare
444 
445   @return The minimum of the two integers
446 
447   @ref Utility
448 **/
449 static inline CeedInt CeedIntMin(CeedInt a, CeedInt b) { return a < b ? a : b; }
450 
451 #endif
452