xref: /petsc/include/petscsystypes.h (revision e6519f9f8d90f4199bf6bb1df3ffafa56045e5d2)
1 /* Portions of this code are under:
2    Copyright (c) 2022 Advanced Micro Devices, Inc. All rights reserved.
3 */
4 
5 #pragma once
6 
7 #include <petscconf.h>
8 #include <petscconf_poison.h>
9 #include <petscfix.h>
10 #include <petscmacros.h> // PETSC_NODISCARD, PETSC_CPP_VERSION
11 #include <stddef.h>
12 
13 /* SUBMANSEC = Sys */
14 
15 #include <limits.h> // INT_MIN, INT_MAX, CHAR_BIT
16 
17 #if defined(__clang__) || (PETSC_CPP_VERSION >= 17)
18   // clang allows both [[nodiscard]] and __attribute__((warn_unused_result)) on type
19   // definitions. GCC, however, does not, so check that we are using C++17 [[nodiscard]]
20   // instead of __attribute__((warn_unused_result))
21   #define PETSC_ERROR_CODE_NODISCARD PETSC_NODISCARD
22 #else
23   #define PETSC_ERROR_CODE_NODISCARD
24 #endif
25 
26 #ifdef PETSC_CLANG_STATIC_ANALYZER
27   #undef PETSC_USE_STRICT_PETSCERRORCODE
28 #endif
29 
30 #ifdef PETSC_USE_STRICT_PETSCERRORCODE
31   #define PETSC_ERROR_CODE_TYPEDEF   typedef
32   #define PETSC_ERROR_CODE_ENUM_NAME PetscErrorCode
33 #else
34   #define PETSC_ERROR_CODE_TYPEDEF
35   #define PETSC_ERROR_CODE_ENUM_NAME
36 #endif
37 
38 /*E
39   PetscErrorCode - Datatype used to return PETSc error codes.
40 
41   Level: beginner
42 
43   Notes:
44   Virtually all PETSc functions return an error code. It is the callers responsibility to check
45   the value of the returned error code after each PETSc call to determine if any errors
46   occurred. A set of convenience macros (e.g. `PetscCall()`, `PetscCallVoid()`) are provided
47   for this purpose. Failing to properly check for errors is not supported, as errors may leave
48   PETSc in an undetermined state.
49 
50   One can retrieve the error string corresponding to a particular error code using
51   `PetscErrorMessage()`.
52 
53   The user can also configure PETSc with the `--with-strict-petscerrorcode` option to enable
54   compiler warnings when the returned error codes are not captured and checked. Users are
55   *heavily* encouraged to opt-in to this option, as it will become enabled by default in a
56   future release.
57 
58   Developer Notes:
59   These are the generic error codes. These error codes are used in many different places in the
60   PETSc source code. The C-string versions are at defined in `PetscErrorStrings[]` in
61   `src/sys/error/err.c`, while the Fortran versions are defined in
62   `src/sys/f90-mod/petscerror.h`. Any changes here must also be made in both locations.
63 
64 .seealso: `PetscErrorMessage()`, `PetscCall()`, `SETERRQ()`
65 E*/
66 PETSC_ERROR_CODE_TYPEDEF enum PETSC_ERROR_CODE_NODISCARD {
67   PETSC_SUCCESS                   = 0,
68   PETSC_ERR_BOOLEAN_MACRO_FAILURE = 1, /* do not use */
69 
70   PETSC_ERR_MIN_VALUE = 54, /* should always be one less than the smallest value */
71 
72   PETSC_ERR_MEM            = 55, /* unable to allocate requested memory */
73   PETSC_ERR_SUP            = 56, /* no support for requested operation */
74   PETSC_ERR_SUP_SYS        = 57, /* no support for requested operation on this computer system */
75   PETSC_ERR_ORDER          = 58, /* operation done in wrong order */
76   PETSC_ERR_SIG            = 59, /* signal received */
77   PETSC_ERR_FP             = 72, /* floating point exception */
78   PETSC_ERR_COR            = 74, /* corrupted PETSc object */
79   PETSC_ERR_LIB            = 76, /* error in library called by PETSc */
80   PETSC_ERR_PLIB           = 77, /* PETSc library generated inconsistent data */
81   PETSC_ERR_MEMC           = 78, /* memory corruption */
82   PETSC_ERR_CONV_FAILED    = 82, /* iterative method (KSP or SNES) failed */
83   PETSC_ERR_USER           = 83, /* user has not provided needed function */
84   PETSC_ERR_SYS            = 88, /* error in system call */
85   PETSC_ERR_POINTER        = 70, /* pointer does not point to valid address */
86   PETSC_ERR_MPI_LIB_INCOMP = 87, /* MPI library at runtime is not compatible with MPI user compiled with */
87 
88   PETSC_ERR_ARG_SIZ          = 60, /* nonconforming object sizes used in operation */
89   PETSC_ERR_ARG_IDN          = 61, /* two arguments not allowed to be the same */
90   PETSC_ERR_ARG_WRONG        = 62, /* wrong argument (but object probably ok) */
91   PETSC_ERR_ARG_CORRUPT      = 64, /* null or corrupted PETSc object as argument */
92   PETSC_ERR_ARG_OUTOFRANGE   = 63, /* input argument, out of range */
93   PETSC_ERR_ARG_BADPTR       = 68, /* invalid pointer argument */
94   PETSC_ERR_ARG_NOTSAMETYPE  = 69, /* two args must be same object type */
95   PETSC_ERR_ARG_NOTSAMECOMM  = 80, /* two args must be same communicators */
96   PETSC_ERR_ARG_WRONGSTATE   = 73, /* object in argument is in wrong state, e.g. unassembled mat */
97   PETSC_ERR_ARG_TYPENOTSET   = 89, /* the type of the object has not yet been set */
98   PETSC_ERR_ARG_INCOMP       = 75, /* two arguments are incompatible */
99   PETSC_ERR_ARG_NULL         = 85, /* argument is null that should not be */
100   PETSC_ERR_ARG_UNKNOWN_TYPE = 86, /* type name doesn't match any registered type */
101 
102   PETSC_ERR_FILE_OPEN       = 65, /* unable to open file */
103   PETSC_ERR_FILE_READ       = 66, /* unable to read from file */
104   PETSC_ERR_FILE_WRITE      = 67, /* unable to write to file */
105   PETSC_ERR_FILE_UNEXPECTED = 79, /* unexpected data in file */
106 
107   PETSC_ERR_MAT_LU_ZRPVT = 71, /* detected a zero pivot during LU factorization */
108   PETSC_ERR_MAT_CH_ZRPVT = 81, /* detected a zero pivot during Cholesky factorization */
109 
110   PETSC_ERR_INT_OVERFLOW   = 84,
111   PETSC_ERR_FLOP_COUNT     = 90,
112   PETSC_ERR_NOT_CONVERGED  = 91,  /* solver did not converge */
113   PETSC_ERR_MISSING_FACTOR = 92,  /* MatGetFactor() failed */
114   PETSC_ERR_OPT_OVERWRITE  = 93,  /* attempted to over write options which should not be changed */
115   PETSC_ERR_WRONG_MPI_SIZE = 94,  /* example/application run with number of MPI ranks it does not support */
116   PETSC_ERR_USER_INPUT     = 95,  /* missing or incorrect user input */
117   PETSC_ERR_GPU_RESOURCE   = 96,  /* unable to load a GPU resource, for example cuBLAS */
118   PETSC_ERR_GPU            = 97,  /* An error from a GPU call, this may be due to lack of resources on the GPU or a true error in the call */
119   PETSC_ERR_MPI            = 98,  /* general MPI error */
120   PETSC_ERR_RETURN         = 99,  /* PetscError() incorrectly returned an error code of 0 */
121   PETSC_ERR_MEM_LEAK       = 100, /* memory alloc/free imbalance */
122   PETSC_ERR_PYTHON         = 101, /* Exception in Python */
123   PETSC_ERR_MAX_VALUE      = 102, /* this is always the one more than the largest error code */
124 
125   /*
126     do not use, exist purely to make the enum bounds equal that of a regular int (so conversion
127     to int in main() is not undefined behavior)
128   */
129   PETSC_ERR_MIN_SIGNED_BOUND_DO_NOT_USE = INT_MIN,
130   PETSC_ERR_MAX_SIGNED_BOUND_DO_NOT_USE = INT_MAX
131 } PETSC_ERROR_CODE_ENUM_NAME;
132 
133 #ifndef PETSC_USE_STRICT_PETSCERRORCODE
134 typedef int PetscErrorCode;
135 
136   /*
137   Needed so that C++ lambdas can deduce the return type as PetscErrorCode from
138   PetscFunctionReturn(PETSC_SUCCESS). Otherwise we get
139 
140   error: return type '(unnamed enum at include/petscsystypes.h:50:1)' must match previous
141   return type 'int' when lambda expression has unspecified explicit return type
142   PetscFunctionReturn(PETSC_SUCCESS);
143   ^
144 */
145   #define PETSC_SUCCESS ((PetscErrorCode)0)
146 #endif
147 
148 #undef PETSC_ERROR_CODE_NODISCARD
149 #undef PETSC_ERROR_CODE_TYPEDEF
150 #undef PETSC_ERROR_CODE_ENUM_NAME
151 
152 /*MC
153     PetscClassId - A unique id used to identify each PETSc class.
154 
155     Level: developer
156 
157     Note:
158     Use `PetscClassIdRegister()` to obtain a new value for a new class being created. Usually
159     XXXInitializePackage() calls it for each class it defines.
160 
161     Developer Note:
162     Internal integer stored in the `_p_PetscObject` data structure. These are all computed by an offset from the lowest one, `PETSC_SMALLEST_CLASSID`.
163 
164 .seealso: `PetscClassIdRegister()`, `PetscLogEventRegister()`, `PetscHeaderCreate()`
165 M*/
166 typedef int PetscClassId;
167 
168 /*MC
169     PetscMPIInt - datatype used to represent 'int' parameters to MPI functions.
170 
171     Level: intermediate
172 
173     Notes:
174     This is always a 32-bit integer, sometimes it is the same as `PetscInt`, but if PETSc was built with `--with-64-bit-indices` but
175     standard C/Fortran integers are 32-bit then this is NOT the same as `PetscInt`; it remains 32-bit.
176 
177     `PetscMPIIntCast`(a,&b) checks if the given `PetscInt` a will fit in a `PetscMPIInt`, if not it
178     generates a `PETSC_ERR_ARG_OUTOFRANGE` error.
179 
180 .seealso: [](stylePetscCount), `PetscBLASInt`, `PetscInt`, `PetscMPIIntCast()`
181 M*/
182 typedef int PetscMPIInt;
183 
184 /* Limit MPI to 32-bits */
185 enum {
186   PETSC_MPI_INT_MIN = INT_MIN,
187   PETSC_MPI_INT_MAX = INT_MAX
188 };
189 
190 /*MC
191     PetscSizeT - datatype used to represent sizes in memory (like `size_t`)
192 
193     Level: intermediate
194 
195     Notes:
196     This is equivalent to `size_t`, but defined for consistency with Fortran, which lacks a native equivalent of `size_t`.
197 
198 .seealso: `PetscInt`, `PetscInt64`, `PetscCount`
199 M*/
200 typedef size_t PetscSizeT;
201 
202 /*MC
203     PetscCount - signed datatype used to represent counts
204 
205     Level: intermediate
206 
207     Notes:
208     This is equivalent to `ptrdiff_t`, but defined for consistency with Fortran, which lacks a native equivalent of `ptrdiff_t`.
209 
210     Use `PetscCount_FMT` to format with `PetscPrintf()`, `printf()`, and related functions.
211 
212 .seealso: [](stylePetscCount), `PetscInt`, `PetscInt64`, `PetscSizeT`
213 M*/
214 typedef ptrdiff_t PetscCount;
215 #define PetscCount_FMT "td"
216 
217 /*MC
218     PetscEnum - datatype used to pass enum types within PETSc functions.
219 
220     Level: intermediate
221 
222 .seealso: `PetscOptionsGetEnum()`, `PetscOptionsEnum()`, `PetscBagRegisterEnum()`
223 M*/
224 typedef enum {
225   ENUM_DUMMY
226 } PetscEnum;
227 
228 typedef short PetscShort;
229 typedef char  PetscChar;
230 typedef float PetscFloat;
231 
232 /*MC
233   PetscInt - PETSc type that represents an integer, used primarily to
234              represent size of arrays and indexing into arrays. Its size can be configured with the option `--with-64-bit-indices` to be either 32-bit (default) or 64-bit.
235 
236   Level: beginner
237 
238   Notes:
239   For MPI calls that require datatypes, use `MPIU_INT` as the datatype for `PetscInt`. It will automatically work correctly regardless of the size of `PetscInt`.
240 
241 .seealso: `PetscBLASInt`, `PetscMPIInt`, `PetscReal`, `PetscScalar`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`, `PetscIntCast()`
242 M*/
243 
244 #if defined(PETSC_HAVE_STDINT_H)
245   #include <stdint.h>
246 #endif
247 #if defined(PETSC_HAVE_INTTYPES_H)
248   #if !defined(__STDC_FORMAT_MACROS)
249     #define __STDC_FORMAT_MACROS /* required for using PRId64 from c++ */
250   #endif
251   #include <inttypes.h>
252   #if !defined(PRId64)
253     #define PRId64 "ld"
254   #endif
255 #endif
256 
257 #if defined(PETSC_HAVE_STDINT_H) && defined(PETSC_HAVE_INTTYPES_H) && (defined(PETSC_HAVE_MPIUNI) || defined(PETSC_HAVE_MPI_INT64_T)) /* MPI_INT64_T is not guaranteed to be a macro */
258 typedef int64_t PetscInt64;
259 
260   #define PETSC_INT64_MIN INT64_MIN
261   #define PETSC_INT64_MAX INT64_MAX
262 
263 #elif (PETSC_SIZEOF_LONG_LONG == 8)
264 typedef long long PetscInt64;
265 
266   #define PETSC_INT64_MIN LLONG_MIN
267   #define PETSC_INT64_MAX LLONG_MAX
268 
269 #elif defined(PETSC_HAVE___INT64)
270 typedef __int64 PetscInt64;
271 
272   #define PETSC_INT64_MIN INT64_MIN
273   #define PETSC_INT64_MAX INT64_MAX
274 
275 #else
276   #error "cannot determine PetscInt64 type"
277 #endif
278 
279 #if PETSC_SIZEOF_SIZE_T == 4
280   #define PETSC_COUNT_MIN INT_MIN
281   #define PETSC_COUNT_MAX INT_MAX
282 #else
283   #define PETSC_COUNT_MIN PETSC_INT64_MIN
284   #define PETSC_COUNT_MAX PETSC_INT64_MAX
285 #endif
286 
287 typedef int32_t PetscInt32;
288 #define PETSC_INT32_MIN INT32_MIN
289 #define PETSC_INT32_MAX INT32_MAX
290 
291 #if defined(PETSC_USE_64BIT_INDICES)
292 typedef PetscInt64 PetscInt;
293 
294   #define PETSC_INT_MIN PETSC_INT64_MIN
295   #define PETSC_INT_MAX PETSC_INT64_MAX
296   #define PetscInt_FMT  PetscInt64_FMT
297 #else
298 typedef int PetscInt;
299 
300 enum {
301   PETSC_INT_MIN = INT_MIN,
302   PETSC_INT_MAX = INT_MAX
303 };
304   #define PetscInt_FMT "d"
305 #endif
306 
307 #define PETSC_UINT16_MAX 65535
308 
309 /* deprecated */
310 #define PETSC_MIN_INT    PETSC_INT_MIN
311 #define PETSC_MAX_INT    PETSC_INT_MAX
312 #define PETSC_MAX_UINT16 PETSC_UINT16_MAX
313 
314 #if defined(PETSC_HAVE_STDINT_H) && defined(PETSC_HAVE_INTTYPES_H) && (defined(PETSC_HAVE_MPIUNI) || defined(PETSC_HAVE_MPI_INT64_T)) /* MPI_INT64_T is not guaranteed to be a macro */
315   #define MPIU_INT64     MPI_INT64_T
316   #define PetscInt64_FMT PRId64
317 #elif (PETSC_SIZEOF_LONG_LONG == 8)
318   #define MPIU_INT64     MPI_LONG_LONG_INT
319   #define PetscInt64_FMT "lld"
320 #elif defined(PETSC_HAVE___INT64)
321   #define MPIU_INT64     MPI_INT64_T
322   #define PetscInt64_FMT "ld"
323 #else
324   #error "cannot determine PetscInt64 type"
325 #endif
326 
327 #define MPIU_INT32     MPI_INT32_T
328 #define PetscInt32_FMT PRId32
329 
330 /*MC
331    PetscBLASInt - datatype used to represent 'int' parameters to BLAS/LAPACK functions.
332 
333    Level: intermediate
334 
335    Notes:
336    Usually this is the same as `PetscInt`, but if PETSc was built with `--with-64-bit-indices` but
337    standard C/Fortran integers are 32-bit then this may not be the same as `PetscInt`,
338    except on some BLAS/LAPACK implementations that support 64-bit integers see the notes below.
339 
340    `PetscErrorCode` `PetscBLASIntCast`(a,&b) checks if the given `PetscInt` a will fit in a `PetscBLASInt`, if not it
341     generates a `PETSC_ERR_ARG_OUTOFRANGE` error
342 
343    Installation Notes\:
344    ./configure automatically determines the size of the integers used by BLAS/LAPACK except when `--with-batch` is used
345    in that situation one must know (by some other means) if the integers used by BLAS/LAPACK are 64-bit and if so pass the flag `--known-64-bit-blas-indices`
346 
347    MATLAB ships with BLAS and LAPACK that use 64-bit integers, for example if you run ./configure with, the option
348     `--with-blaslapack-lib`=[/Applications/MATLAB_R2010b.app/bin/maci64/libmwblas.dylib,/Applications/MATLAB_R2010b.app/bin/maci64/libmwlapack.dylib]
349 
350    MKL ships with both 32 and 64-bit integer versions of the BLAS and LAPACK. If you pass the flag `-with-64-bit-blas-indices` PETSc will link
351    against the 64-bit version, otherwise it uses the 32-bit version
352 
353    OpenBLAS can be built to use 64-bit integers. The ./configure options `--download-openblas` `-with-64-bit-blas-indices` will build a 64-bit integer version
354 
355    External packages such as hypre, ML, SuperLU etc do not provide any support for passing 64-bit integers to BLAS/LAPACK so cannot
356    be used with PETSc when PETSc links against 64-bit integer BLAS/LAPACK. ./configure will generate an error if you attempt to link PETSc against any of
357    these external libraries while using 64-bit integer BLAS/LAPACK.
358 
359 .seealso: `PetscMPIInt`, `PetscInt`, `PetscBLASIntCast()`
360 M*/
361 #if defined(PETSC_HAVE_64BIT_BLAS_INDICES)
362 typedef PetscInt64 PetscBLASInt;
363 
364   #define PETSC_BLAS_INT_MIN PETSC_INT64_MIN
365   #define PETSC_BLAS_INT_MAX PETSC_INT64_MAX
366   #define PetscBLASInt_FMT   PetscInt64_FMT
367 #else
368 typedef int PetscBLASInt;
369 
370 enum {
371   PETSC_BLAS_INT_MIN = INT_MIN,
372   PETSC_BLAS_INT_MAX = INT_MAX
373 };
374 
375   #define PetscBLASInt_FMT "d"
376 #endif
377 
378 /*MC
379    PetscCuBLASInt - datatype used to represent 'int' parameters to cuBLAS/cuSOLVER functions.
380 
381    Level: intermediate
382 
383    Notes:
384    As of this writing `PetscCuBLASInt` is always the system `int`.
385 
386   `PetscErrorCode` `PetscCuBLASIntCast`(a,&b) checks if the given `PetscInt` a will fit in a `PetscCuBLASInt`, if not it
387    generates a `PETSC_ERR_ARG_OUTOFRANGE` error
388 
389 .seealso: `PetscBLASInt`, `PetscMPIInt`, `PetscInt`, `PetscCuBLASIntCast()`
390 M*/
391 typedef int PetscCuBLASInt;
392 
393 enum {
394   PETSC_CUBLAS_INT_MIN = INT_MIN,
395   PETSC_CUBLAS_INT_MAX = INT_MAX
396 };
397 
398 /*MC
399    PetscHipBLASInt - datatype used to represent 'int' parameters to hipBLAS/hipSOLVER functions.
400 
401    Level: intermediate
402 
403    Notes:
404    `PetscHipBLASInt` is always the system `int`.
405 
406    `PetscErrorCode` `PetscHipBLASIntCast`(a,&b) checks if the given `PetscInt` a will fit in a `PetscHipBLASInt`, if not it
407    generates a `PETSC_ERR_ARG_OUTOFRANGE` error
408 
409 .seealso: `PetscBLASInt`, `PetscMPIInt`, `PetscInt`, `PetscHipBLASIntCast()`
410 M*/
411 typedef int PetscHipBLASInt;
412 
413 enum {
414   PETSC_HIPBLAS_INT_MIN = INT_MIN,
415   PETSC_HIPBLAS_INT_MAX = INT_MAX
416 };
417 
418 /*MC
419    PetscExodusIIInt - datatype used to represent 'int' parameters to ExodusII functions.
420 
421    Level: intermediate
422 
423    Notes:
424    This is the same as `int`
425 
426 .seealso: `PetscMPIInt`, `PetscInt`, `PetscExodusIIFloat`, `PetscBLASIntCast()`
427 M*/
428 typedef int PetscExodusIIInt;
429 #define PetscExodusIIInt_FMT "d"
430 
431 /*MC
432    PetscExodusIIFloat - datatype used to represent 'float' parameters to ExodusII functions.
433 
434    Level: intermediate
435 
436    Notes:
437    This is the same as `float`
438 
439 .seealso: `PetscMPIInt`, `PetscInt`, `PetscExodusIIInt`, `PetscBLASIntCast()`
440 M*/
441 typedef float PetscExodusIIFloat;
442 
443 /*E
444    PetscBool  - Logical variable. Actually an enum in C and a logical in Fortran.
445 
446    Level: beginner
447 
448    Developer Note:
449    Why have `PetscBool`, why not use bool in C? The problem is that K and R C, C99 and C++ all have different mechanisms for
450    Boolean values. It is not easy to have a simple macro that will work properly in all circumstances with all three mechanisms.
451 
452 .seealso: `PETSC_TRUE`, `PETSC_FALSE`, `PetscNot()`, `PetscBool3`
453 E*/
454 typedef enum {
455   PETSC_FALSE,
456   PETSC_TRUE
457 } PetscBool;
458 PETSC_EXTERN const char *const PetscBools[];
459 
460 /*E
461    PetscBool3  - Ternary logical variable. Actually an enum in C and a 4 byte integer in Fortran.
462 
463    Level: beginner
464 
465    Note:
466    Should not be used with the if (flg) or if (!flg) syntax.
467 
468 .seealso: `PETSC_TRUE`, `PETSC_FALSE`, `PetscNot()`, `PETSC_BOOL3_TRUE`, `PETSC_BOOL3_FALSE`, `PETSC_BOOL3_UNKNOWN`
469 E*/
470 typedef enum {
471   PETSC_BOOL3_FALSE,
472   PETSC_BOOL3_TRUE,
473   PETSC_BOOL3_UNKNOWN = -1 /* the value is unknown at the time of query, but might be determined later */
474 } PetscBool3;
475 
476 #define PetscBool3ToBool(a) ((a) == PETSC_BOOL3_TRUE ? PETSC_TRUE : PETSC_FALSE)
477 #define PetscBoolToBool3(a) ((a) == PETSC_TRUE ? PETSC_BOOL3_TRUE : PETSC_BOOL3_FALSE)
478 
479 /*MC
480    PetscReal - PETSc type that represents a real number version of `PetscScalar`
481 
482    Level: beginner
483 
484    Notes:
485    For MPI calls that require datatypes, use `MPIU_REAL` as the datatype for `PetscReal` and `MPIU_SUM`, `MPIU_MAX`, etc. for operations.
486    They will automatically work correctly regardless of the size of `PetscReal`.
487 
488    See `PetscScalar` for details on how to ./configure the size of `PetscReal`.
489 
490 .seealso: `PetscScalar`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`
491 M*/
492 
493 #if defined(PETSC_USE_REAL_SINGLE)
494 typedef float PetscReal;
495 #elif defined(PETSC_USE_REAL_DOUBLE)
496 typedef double PetscReal;
497 #elif defined(PETSC_USE_REAL___FLOAT128)
498   #if defined(__cplusplus)
499 extern "C" {
500   #endif
501   #include <quadmath.h>
502   #if defined(__cplusplus)
503 }
504   #endif
505 typedef __float128 PetscReal;
506 #elif defined(PETSC_USE_REAL___FP16)
507 typedef __fp16 PetscReal;
508 #endif /* PETSC_USE_REAL_* */
509 
510 /*MC
511    PetscComplex - PETSc type that represents a complex number with precision matching that of `PetscReal`.
512 
513    Synopsis:
514    #include <petscsys.h>
515    PetscComplex number = 1. + 2.*PETSC_i;
516 
517    Level: beginner
518 
519    Notes:
520    For MPI calls that require datatypes, use `MPIU_COMPLEX` as the datatype for `PetscComplex` and `MPIU_SUM` etc for operations.
521    They will automatically work correctly regardless of the size of `PetscComplex`.
522 
523    See `PetscScalar` for details on how to ./configure the size of `PetscReal`
524 
525    Complex numbers are automatically available if PETSc was able to find a working complex implementation
526 
527     PETSc has a 'fix' for complex numbers to support expressions such as `std::complex<PetscReal>` + `PetscInt`, which are not supported by the standard
528     C++ library, but are convenient for petsc users. If the C++ compiler is able to compile code in `petsccxxcomplexfix.h` (This is checked by
529     configure), we include `petsccxxcomplexfix.h` to provide this convenience.
530 
531     If the fix causes conflicts, or one really does not want this fix for a particular C++ file, one can define `PETSC_SKIP_CXX_COMPLEX_FIX`
532     at the beginning of the C++ file to skip the fix.
533 
534 .seealso: `PetscReal`, `PetscScalar`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`, `PETSC_i`
535 M*/
536 #if !defined(PETSC_SKIP_COMPLEX)
537   #if defined(PETSC_CLANGUAGE_CXX)
538     #if !defined(PETSC_USE_REAL___FP16) && !defined(PETSC_USE_REAL___FLOAT128)
539       #if defined(__cplusplus) && defined(PETSC_HAVE_CXX_COMPLEX) /* enable complex for library code */
540         #define PETSC_HAVE_COMPLEX 1
541       #elif !defined(__cplusplus) && defined(PETSC_HAVE_C99_COMPLEX) && defined(PETSC_HAVE_CXX_COMPLEX) /* User code only - conditional on library code complex support */
542         #define PETSC_HAVE_COMPLEX 1
543       #endif
544     #elif defined(PETSC_USE_REAL___FLOAT128) && defined(PETSC_HAVE_C99_COMPLEX)
545       #define PETSC_HAVE_COMPLEX 1
546     #endif
547   #else /* !PETSC_CLANGUAGE_CXX */
548     #if !defined(PETSC_USE_REAL___FP16)
549       #if !defined(__cplusplus) && defined(PETSC_HAVE_C99_COMPLEX) /* enable complex for library code */
550         #define PETSC_HAVE_COMPLEX 1
551       #elif defined(__cplusplus) && defined(PETSC_HAVE_C99_COMPLEX) && defined(PETSC_HAVE_CXX_COMPLEX) /* User code only - conditional on library code complex support */
552         #define PETSC_HAVE_COMPLEX 1
553       #endif
554     #endif
555   #endif /* PETSC_CLANGUAGE_CXX */
556 #endif   /* !PETSC_SKIP_COMPLEX */
557 
558 #if defined(PETSC_HAVE_COMPLEX)
559   #if defined(__cplusplus) /* C++ complex support */
560     /* Locate a C++ complex template library */
561     #if defined(PETSC_DESIRE_KOKKOS_COMPLEX) /* Defined in petscvec_kokkos.hpp for *.kokkos.cxx files */
562       #define petsccomplexlib Kokkos
563       #include <Kokkos_Complex.hpp>
564     #elif (defined(__CUDACC__) && defined(PETSC_HAVE_CUDA)) || (defined(__HIPCC__) && defined(PETSC_HAVE_HIP))
565       #define petsccomplexlib thrust
566       #include <thrust/complex.h>
567     #elif defined(PETSC_USE_REAL___FLOAT128)
568       #include <complex.h>
569     #else
570       #define petsccomplexlib std
571       #include <complex>
572     #endif
573 
574     /* Define PetscComplex based on the precision */
575     #if defined(PETSC_USE_REAL_SINGLE)
576 typedef petsccomplexlib::complex<float> PetscComplex;
577     #elif defined(PETSC_USE_REAL_DOUBLE)
578 typedef petsccomplexlib::complex<double> PetscComplex;
579     #elif defined(PETSC_USE_REAL___FLOAT128)
580 typedef __complex128 PetscComplex;
581     #endif
582 
583     /* Include a PETSc C++ complex 'fix'. Check PetscComplex manual page for details */
584     #if defined(PETSC_HAVE_CXX_COMPLEX_FIX) && !defined(PETSC_SKIP_CXX_COMPLEX_FIX)
585       #include <petsccxxcomplexfix.h>
586     #endif
587   #else /* c99 complex support */
588     #include <complex.h>
589     #if defined(PETSC_USE_REAL_SINGLE) || defined(PETSC_USE_REAL___FP16)
590 typedef float _Complex PetscComplex;
591     #elif defined(PETSC_USE_REAL_DOUBLE)
592 typedef double _Complex PetscComplex;
593     #elif defined(PETSC_USE_REAL___FLOAT128)
594 typedef __complex128 PetscComplex;
595     #endif /* PETSC_USE_REAL_* */
596   #endif   /* !__cplusplus */
597 #endif     /* PETSC_HAVE_COMPLEX */
598 
599 /*MC
600    PetscScalar - PETSc type that represents either a double precision real number, a double precision
601                  complex number, a single precision real number, a __float128 real or complex or a __fp16 real - if the code is configured
602                  with `--with-scalar-type`=real,complex `--with-precision`=single,double,__float128,__fp16
603 
604    Level: beginner
605 
606    Note:
607    For MPI calls that require datatypes, use `MPIU_SCALAR` as the datatype for `PetscScalar` and `MPIU_SUM`, etc for operations. They will automatically work correctly regardless of the size of `PetscScalar`.
608 
609 .seealso: `PetscReal`, `PetscComplex`, `PetscInt`, `MPIU_REAL`, `MPIU_SCALAR`, `MPIU_COMPLEX`, `MPIU_INT`, `PetscRealPart()`, `PetscImaginaryPart()`
610 M*/
611 
612 #if defined(PETSC_USE_COMPLEX) && defined(PETSC_HAVE_COMPLEX)
613 typedef PetscComplex PetscScalar;
614 #else  /* PETSC_USE_COMPLEX */
615 typedef PetscReal PetscScalar;
616 #endif /* PETSC_USE_COMPLEX */
617 
618 /*E
619     PetscCopyMode  - Determines how an array or `PetscObject` passed to certain functions is copied or retained by the aggregate `PetscObject`
620 
621    Values for array input:
622 +   `PETSC_COPY_VALUES` - the array values are copied into new space, the user is free to reuse or delete the passed in array
623 .   `PETSC_OWN_POINTER` - the array values are NOT copied, the object takes ownership of the array and will free it later, the user cannot change or
624                           delete the array. The array MUST have been obtained with `PetscMalloc()`. Hence this mode cannot be used in Fortran.
625 -   `PETSC_USE_POINTER` - the array values are NOT copied, the object uses the array but does NOT take ownership of the array. The user cannot use
626                           the array but the user must delete the array after the object is destroyed.
627 
628    Values for PetscObject:
629 +   `PETSC_COPY_VALUES` - the input `PetscObject` is cloned into the aggregate `PetscObject`; the user is free to reuse/modify the input `PetscObject` without side effects.
630 .   `PETSC_OWN_POINTER` - the input `PetscObject` is referenced by pointer (with reference count), thus should not be modified by the user.
631                           increases its reference count).
632 -   `PETSC_USE_POINTER` - invalid for `PetscObject` inputs.
633 
634    Level: beginner
635 
636 .seealso: `PetscInsertMode`
637 E*/
638 typedef enum {
639   PETSC_COPY_VALUES,
640   PETSC_OWN_POINTER,
641   PETSC_USE_POINTER
642 } PetscCopyMode;
643 PETSC_EXTERN const char *const PetscCopyModes[];
644 
645 /*MC
646     PETSC_FALSE - False value of `PetscBool`
647 
648     Level: beginner
649 
650     Note:
651     Zero integer
652 
653 .seealso: `PetscBool`, `PetscBool3`, `PETSC_TRUE`
654 M*/
655 
656 /*MC
657     PETSC_TRUE - True value of `PetscBool`
658 
659     Level: beginner
660 
661     Note:
662     Nonzero integer
663 
664 .seealso: `PetscBool`, `PetscBool3`, `PETSC_FALSE`
665 M*/
666 
667 /*MC
668     PetscLogDouble - Used for logging times
669 
670   Level: developer
671 
672   Note:
673   Contains double precision numbers that are not used in the numerical computations, but rather in logging, timing etc.
674 
675 .seealso: `PetscBool`, `PetscDataType`
676 M*/
677 typedef double PetscLogDouble;
678 
679 /*E
680     PetscDataType - Used for handling different basic data types.
681 
682    Level: beginner
683 
684    Notes:
685    Use of this should be avoided if one can directly use `MPI_Datatype` instead.
686 
687    `PETSC_INT` is the datatype for a `PetscInt`, regardless of whether it is 4 or 8 bytes.
688    `PETSC_REAL`, `PETSC_COMPLEX` and `PETSC_SCALAR` are the datatypes for `PetscReal`, `PetscComplex` and `PetscScalar`, regardless of their sizes.
689 
690    Developer Notes:
691    It would be nice if we could always just use MPI Datatypes, why can we not?
692 
693    If you change any values in `PetscDatatype` make sure you update their usage in
694    share/petsc/matlab/PetscBagRead.m and share/petsc/matlab/@PetscOpenSocket/read/write.m
695 
696    TODO:
697    Remove use of improper `PETSC_ENUM`
698 
699 .seealso: `PetscBinaryRead()`, `PetscBinaryWrite()`, `PetscDataTypeToMPIDataType()`,
700           `PetscDataTypeGetSize()`
701 E*/
702 typedef enum {
703   PETSC_DATATYPE_UNKNOWN = 0,
704   PETSC_DOUBLE           = 1,
705   PETSC_COMPLEX          = 2,
706   PETSC_LONG             = 3,
707   PETSC_SHORT            = 4,
708   PETSC_FLOAT            = 5,
709   PETSC_CHAR             = 6,
710   PETSC_BIT_LOGICAL      = 7,
711   PETSC_ENUM             = 8,
712   PETSC_BOOL             = 9,
713   PETSC___FLOAT128       = 10,
714   PETSC_OBJECT           = 11,
715   PETSC_FUNCTION         = 12,
716   PETSC_STRING           = 13,
717   PETSC___FP16           = 14,
718   PETSC_STRUCT           = 15,
719   PETSC_INT              = 16,
720   PETSC_INT64            = 17,
721   PETSC_COUNT            = 18,
722   PETSC_INT32            = 19,
723 } PetscDataType;
724 PETSC_EXTERN const char *const PetscDataTypes[];
725 
726 #if defined(PETSC_USE_REAL_SINGLE)
727   #define PETSC_REAL PETSC_FLOAT
728 #elif defined(PETSC_USE_REAL_DOUBLE)
729   #define PETSC_REAL PETSC_DOUBLE
730 #elif defined(PETSC_USE_REAL___FLOAT128)
731   #define PETSC_REAL PETSC___FLOAT128
732 #elif defined(PETSC_USE_REAL___FP16)
733   #define PETSC_REAL PETSC___FP16
734 #else
735   #define PETSC_REAL PETSC_DOUBLE
736 #endif
737 
738 #if defined(PETSC_USE_COMPLEX)
739   #define PETSC_SCALAR PETSC_COMPLEX
740 #else
741   #define PETSC_SCALAR PETSC_REAL
742 #endif
743 
744 #define PETSC_FORTRANADDR PETSC_LONG
745 
746 /*S
747   PetscToken - 'Token' used for managing tokenizing strings
748 
749   Level: intermediate
750 
751 .seealso: `PetscTokenCreate()`, `PetscTokenFind()`, `PetscTokenDestroy()`
752 S*/
753 typedef struct _p_PetscToken *PetscToken;
754 
755 /*S
756    PetscObject - any PETSc object, for example: `PetscViewer`, `Mat`, `Vec`, `KSP`, `DM`
757 
758    Level: beginner
759 
760    Notes:
761    This is the base class from which all PETSc objects are derived.
762 
763    In certain situations one can cast an object, for example a `Vec`, to a `PetscObject` with (`PetscObject`)vec
764 
765 .seealso: `PetscObjectDestroy()`, `PetscObjectView()`, `PetscObjectGetName()`, `PetscObjectSetName()`, `PetscObjectReference()`, `PetscObjectDereference()`
766 S*/
767 typedef struct _p_PetscObject *PetscObject;
768 
769 /*MC
770     PetscObjectId - unique integer Id for a `PetscObject`
771 
772     Level: developer
773 
774     Note:
775     Unlike pointer values, object ids are never reused so one may save a `PetscObjectId` and compare it to one obtained later from a `PetscObject` to determine
776     if the objects are the same. Never compare two object pointer values.
777 
778 .seealso: `PetscObjectState`, `PetscObjectGetId()`
779 M*/
780 typedef PetscInt64 PetscObjectId;
781 
782 /*MC
783     PetscObjectState - integer state for a `PetscObject`
784 
785     Level: developer
786 
787     Note:
788     Object state is always-increasing and (for objects that track state) can be used to determine if an object has
789     changed since the last time you interacted with it.  It is 64-bit so that it will not overflow for a very long time.
790 
791 .seealso: `PetscObjectId`, `PetscObjectStateGet()`, `PetscObjectStateIncrease()`, `PetscObjectStateSet()`
792 M*/
793 typedef PetscInt64 PetscObjectState;
794 
795 /*S
796      PetscFunctionList - Linked list of functions, possibly stored in dynamic libraries, accessed
797       by string name
798 
799    Level: advanced
800 
801 .seealso: `PetscFunctionListAdd()`, `PetscFunctionListDestroy()`
802 S*/
803 typedef struct _n_PetscFunctionList *PetscFunctionList;
804 
805 /*E
806   PetscFileMode - Access mode for a file.
807 
808   Values:
809 +  `FILE_MODE_UNDEFINED`     - initial invalid value
810 .  `FILE_MODE_READ`          - open a file at its beginning for reading
811 .  `FILE_MODE_WRITE`         - open a file at its beginning for writing (will create if the file does not exist)
812 .  `FILE_MODE_APPEND`        - open a file at end for writing
813 .  `FILE_MODE_UPDATE`        - open a file for updating, meaning for reading and writing
814 -  `FILE_MODE_APPEND_UPDATE` - open a file for updating, meaning for reading and writing, at the end
815 
816   Level: beginner
817 
818 .seealso: `PetscViewerFileSetMode()`
819 E*/
820 typedef enum {
821   FILE_MODE_UNDEFINED = -1,
822   FILE_MODE_READ      = 0,
823   FILE_MODE_WRITE,
824   FILE_MODE_APPEND,
825   FILE_MODE_UPDATE,
826   FILE_MODE_APPEND_UPDATE
827 } PetscFileMode;
828 PETSC_EXTERN const char *const PetscFileModes[];
829 
830 typedef void *PetscDLHandle;
831 typedef enum {
832   PETSC_DL_DECIDE = 0,
833   PETSC_DL_NOW    = 1,
834   PETSC_DL_LOCAL  = 2
835 } PetscDLMode;
836 
837 /*S
838    PetscObjectList - Linked list of PETSc objects, each accessible by string name
839 
840    Level: developer
841 
842    Note:
843    Used by `PetscObjectCompose()` and `PetscObjectQuery()`
844 
845 .seealso: `PetscObjectListAdd()`, `PetscObjectListDestroy()`, `PetscObjectListFind()`, `PetscObjectCompose()`, `PetscObjectQuery()`, `PetscFunctionList`
846 S*/
847 typedef struct _n_PetscObjectList *PetscObjectList;
848 
849 /*S
850    PetscDLLibrary - Linked list of dynamic libraries to search for functions
851 
852    Level: developer
853 
854 .seealso: `PetscDLLibraryOpen()`
855 S*/
856 typedef struct _n_PetscDLLibrary *PetscDLLibrary;
857 
858 /*S
859    PetscContainer - Simple PETSc object that contains a pointer to any required data
860 
861    Level: advanced
862 
863    Note:
864    This is useful to attach arbitrary data to a `PetscObject` with `PetscObjectCompose()` and `PetscObjectQuery()`
865 
866 .seealso: `PetscObject`, `PetscContainerCreate()`, `PetscObjectCompose()`, `PetscObjectQuery()`
867 S*/
868 typedef struct _p_PetscContainer *PetscContainer;
869 
870 /*S
871    PetscRandom - Abstract PETSc object that manages generating random numbers
872 
873    Level: intermediate
874 
875 .seealso: `PetscRandomCreate()`, `PetscRandomGetValue()`, `PetscRandomType`
876 S*/
877 typedef struct _p_PetscRandom *PetscRandom;
878 
879 /*
880    In binary files variables are stored using the following lengths,
881   regardless of how they are stored in memory on any one particular
882   machine. Use these rather than sizeof() in computing sizes for
883   PetscBinarySeek().
884 */
885 #define PETSC_BINARY_INT_SIZE    (32 / 8)
886 #define PETSC_BINARY_FLOAT_SIZE  (32 / 8)
887 #define PETSC_BINARY_CHAR_SIZE   (8 / 8)
888 #define PETSC_BINARY_SHORT_SIZE  (16 / 8)
889 #define PETSC_BINARY_DOUBLE_SIZE (64 / 8)
890 #define PETSC_BINARY_SCALAR_SIZE sizeof(PetscScalar)
891 
892 /*E
893   PetscBinarySeekType - argument to `PetscBinarySeek()`
894 
895   Values:
896 +  `PETSC_BINARY_SEEK_SET` - offset is an absolute location in the file
897 .  `PETSC_BINARY_SEEK_CUR` - offset is an offset from the current location of the file pointer
898 -  `PETSC_BINARY_SEEK_END` - offset is an offset from the end of the file
899 
900   Level: advanced
901 
902 .seealso: `PetscBinarySeek()`, `PetscBinarySynchronizedSeek()`
903 E*/
904 typedef enum {
905   PETSC_BINARY_SEEK_SET = 0,
906   PETSC_BINARY_SEEK_CUR = 1,
907   PETSC_BINARY_SEEK_END = 2
908 } PetscBinarySeekType;
909 
910 /*E
911    PetscBuildTwoSidedType - algorithm for setting up two-sided communication for use with `PetscSF`
912 
913    Values:
914 +  `PETSC_BUILDTWOSIDED_ALLREDUCE`  - classical algorithm using an `MPI_Allreduce()` with
915                                       a buffer of length equal to the communicator size. Not memory-scalable due to
916                                       the large reduction size. Requires only an MPI-1 implementation.
917 .  `PETSC_BUILDTWOSIDED_IBARRIER`   - nonblocking algorithm based on `MPI_Issend()` and `MPI_Ibarrier()`.
918                                       Proved communication-optimal in Hoefler, Siebert, and Lumsdaine (2010). Requires an MPI-3 implementation.
919 -  `PETSC_BUILDTWOSIDED_REDSCATTER` - similar to above, but use more optimized function
920                                       that only communicates the part of the reduction that is necessary.  Requires an MPI-2 implementation.
921 
922    Level: developer
923 
924 .seealso: `PetscCommBuildTwoSided()`, `PetscCommBuildTwoSidedSetType()`, `PetscCommBuildTwoSidedGetType()`
925 E*/
926 typedef enum {
927   PETSC_BUILDTWOSIDED_NOTSET     = -1,
928   PETSC_BUILDTWOSIDED_ALLREDUCE  = 0,
929   PETSC_BUILDTWOSIDED_IBARRIER   = 1,
930   PETSC_BUILDTWOSIDED_REDSCATTER = 2
931   /* Updates here must be accompanied by updates in finclude/petscsys.h and the string array in mpits.c */
932 } PetscBuildTwoSidedType;
933 PETSC_EXTERN const char *const PetscBuildTwoSidedTypes[];
934 
935 /* NOTE: If you change this, you must also change the values in src/vec/f90-mod/petscvec.h */
936 /*E
937   InsertMode - How the entries are combined with the current values in the vectors or matrices
938 
939   Values:
940 +  `NOT_SET_VALUES`    - do not actually use the values
941 .  `INSERT_VALUES`     - replace the current values with the provided values, unless the index is marked as constrained by the `PetscSection`
942 .  `ADD_VALUES`        - add the values to the current values, unless the index is marked as constrained by the `PetscSection`
943 .  `MAX_VALUES`        - use the maximum of each current value and provided value
944 .  `MIN_VALUES`        - use the minimum of each current value and provided value
945 .  `INSERT_ALL_VALUES` - insert, even if indices that are not marked as constrained by the `PetscSection`
946 .  `ADD_ALL_VALUES`    - add, even if indices that are not marked as constrained by the `PetscSection`
947 .  `INSERT_BC_VALUES`  - insert, but ignore indices that are not marked as constrained by the `PetscSection`
948 -  `ADD_BC_VALUES`     - add, but ignore indices that are not marked as constrained by the `PetscSection`
949 
950   Level: beginner
951 
952   Note:
953   The `PetscSection` that determines the effects of the `InsertMode` values can be obtained by the `Vec` object with `VecGetDM()`
954   and `DMGetLocalSection()`.
955 
956   Not all options are supported for all operations or PETSc object types.
957 
958 .seealso: `VecSetValues()`, `MatSetValues()`, `VecSetValue()`, `VecSetValuesBlocked()`,
959           `VecSetValuesLocal()`, `VecSetValuesBlockedLocal()`, `MatSetValuesBlocked()`,
960           `MatSetValuesBlockedLocal()`, `MatSetValuesLocal()`, `VecScatterBegin()`, `VecScatterEnd()`
961 E*/
962 typedef enum {
963   NOT_SET_VALUES,
964   INSERT_VALUES,
965   ADD_VALUES,
966   MAX_VALUES,
967   MIN_VALUES,
968   INSERT_ALL_VALUES,
969   ADD_ALL_VALUES,
970   INSERT_BC_VALUES,
971   ADD_BC_VALUES
972 } InsertMode;
973 
974 /*MC
975     INSERT_VALUES - Put a value into a vector or matrix, overwrites any previous value
976 
977     Level: beginner
978 
979 .seealso: `InsertMode`, `VecSetValues()`, `MatSetValues()`, `VecSetValue()`, `VecSetValuesBlocked()`,
980           `VecSetValuesLocal()`, `VecSetValuesBlockedLocal()`, `MatSetValuesBlocked()`, `ADD_VALUES`,
981           `MatSetValuesBlockedLocal()`, `MatSetValuesLocal()`, `VecScatterBegin()`, `VecScatterEnd()`, `MAX_VALUES`
982 M*/
983 
984 /*MC
985     ADD_VALUES - Adds a value into a vector or matrix, if there previously was no value, just puts the
986                  value into that location
987 
988     Level: beginner
989 
990 .seealso: `InsertMode`, `VecSetValues()`, `MatSetValues()`, `VecSetValue()`, `VecSetValuesBlocked()`,
991           `VecSetValuesLocal()`, `VecSetValuesBlockedLocal()`, `MatSetValuesBlocked()`, `INSERT_VALUES`,
992           `MatSetValuesBlockedLocal()`, `MatSetValuesLocal()`, `VecScatterBegin()`, `VecScatterEnd()`, `MAX_VALUES`
993 M*/
994 
995 /*MC
996     MAX_VALUES - Puts the maximum of the scattered/gathered value and the current value into each location
997 
998     Level: beginner
999 
1000 .seealso: `InsertMode`, `VecScatterBegin()`, `VecScatterEnd()`, `ADD_VALUES`, `INSERT_VALUES`
1001 M*/
1002 
1003 /*MC
1004     MIN_VALUES - Puts the minimal of the scattered/gathered value and the current value into each location
1005 
1006     Level: beginner
1007 
1008 .seealso: `InsertMode`, `VecScatterBegin()`, `VecScatterEnd()`, `ADD_VALUES`, `INSERT_VALUES`
1009 M*/
1010 
1011 /*S
1012    PetscSubcomm - A decomposition of an MPI communicator into subcommunicators
1013 
1014    Values:
1015 +   `PETSC_SUBCOMM_GENERAL`    - similar to `MPI_Comm_split()` each process sets the new communicator (color) they will belong to and the order within that communicator
1016 .   `PETSC_SUBCOMM_CONTIGUOUS` - each new communicator contains a set of process with contiguous ranks in the original MPI communicator
1017 -   `PETSC_SUBCOMM_INTERLACED` - each new communictor contains a set of processes equally far apart in rank from the others in that new communicator
1018 
1019    Sample Usage:
1020 .vb
1021        PetscSubcommCreate()
1022        PetscSubcommSetNumber()
1023        PetscSubcommSetType(PETSC_SUBCOMM_INTERLACED);
1024        ccomm = PetscSubcommChild()
1025        PetscSubcommDestroy()
1026 .ve
1027 
1028    Example:
1029    Consider a communicator with six processes split into 3 subcommunicators.
1030 .vb
1031    PETSC_SUBCOMM_CONTIGUOUS - the first communicator contains rank 0,1  the second rank 2,3 and the third rank 4,5 in the original ordering of the original communicator
1032    PETSC_SUBCOMM_INTERLACED - the first communicator contains rank 0,3, the second 1,4 and the third 2,5
1033 .ve
1034 
1035    Level: advanced
1036 
1037    Note:
1038    After a call to `PetscSubcommSetType()`, `PetscSubcommSetTypeGeneral()`, or `PetscSubcommSetFromOptions()` one may call
1039 .vb
1040      PetscSubcommChild() returns the associated subcommunicator on this process
1041      PetscSubcommContiguousParent() returns a parent communitor but with all child of the same subcommunicator having contiguous rank
1042 .ve
1043 
1044    Developer Note:
1045    This is used in objects such as `PCREDUNDANT` to manage the subcommunicators on which the redundant computations
1046    are performed.
1047 
1048 .seealso: `PetscSubcommCreate()`, `PetscSubcommSetNumber()`, `PetscSubcommSetType()`, `PetscSubcommView()`, `PetscSubcommSetFromOptions()`
1049 S*/
1050 typedef struct _n_PetscSubcomm *PetscSubcomm;
1051 typedef enum {
1052   PETSC_SUBCOMM_GENERAL    = 0,
1053   PETSC_SUBCOMM_CONTIGUOUS = 1,
1054   PETSC_SUBCOMM_INTERLACED = 2
1055 } PetscSubcommType;
1056 PETSC_EXTERN const char *const PetscSubcommTypes[];
1057 
1058 /*S
1059    PetscHeap - A simple class for managing heaps
1060 
1061    Level: intermediate
1062 
1063 .seealso: `PetscHeapCreate()`, `PetscHeapAdd()`, `PetscHeapPop()`, `PetscHeapPeek()`, `PetscHeapStash()`, `PetscHeapUnstash()`, `PetscHeapView()`, `PetscHeapDestroy()`
1064 S*/
1065 typedef struct _PetscHeap *PetscHeap;
1066 
1067 typedef struct _n_PetscShmComm *PetscShmComm;
1068 typedef struct _n_PetscOmpCtrl *PetscOmpCtrl;
1069 
1070 /*S
1071    PetscSegBuffer - a segmented extendable buffer
1072 
1073    Level: developer
1074 
1075 .seealso: `PetscSegBufferCreate()`, `PetscSegBufferGet()`, `PetscSegBufferExtract()`, `PetscSegBufferDestroy()`
1076 S*/
1077 typedef struct _n_PetscSegBuffer *PetscSegBuffer;
1078 
1079 typedef struct _n_PetscOptionsHelpPrinted *PetscOptionsHelpPrinted;
1080 
1081 /*S
1082      PetscBT - PETSc bitarrays, efficient storage of arrays of boolean values
1083 
1084      Level: advanced
1085 
1086      Notes:
1087      The following routines do not have their own manual pages
1088 
1089 .vb
1090      PetscBTCreate(m,&bt)         - creates a bit array with enough room to hold m values
1091      PetscBTDestroy(&bt)          - destroys the bit array
1092      PetscBTMemzero(m,bt)         - zeros the entire bit array (sets all values to false)
1093      PetscBTSet(bt,index)         - sets a particular entry as true
1094      PetscBTClear(bt,index)       - sets a particular entry as false
1095      PetscBTLookup(bt,index)      - returns the value
1096      PetscBTLookupSet(bt,index)   - returns the value and then sets it true
1097      PetscBTLookupClear(bt,index) - returns the value and then sets it false
1098      PetscBTLength(m)             - returns number of bytes in array with m bits
1099      PetscBTView(m,bt,viewer)     - prints all the entries in a bit array
1100 .ve
1101 
1102     PETSc does not check error flags on `PetscBTLookup()`, `PetcBTLookupSet()`, `PetscBTLength()` because error checking
1103     would cost hundreds more cycles then the operation.
1104 
1105 S*/
1106 typedef char *PetscBT;
1107 
1108 /* The number of bits in a byte */
1109 #define PETSC_BITS_PER_BYTE CHAR_BIT
1110