Documentation: Changes: 3.12

CHANGES in the PETSc 3.12 Version

General:

PetscRoundReal() has been removed, since the math routine round() is not supported on all systems: perhaps use PetscCeilReal() or PetscFloorReal()<\li>
The legacy and cmake compile systems (make all-legacy and all-cmake) are removed
make gnumake is now make libs
PetscArraycmp() should be used instead of PetscMemcmp(), it takes a count argument instead of a byte argument
PetscArraycpy() should be used instead of PetscMemcpy(), it takes a count argument instead of a byte argument
PetscArrayzero() should be used instead of PetscMemzero(), it takes a count argument instead of a byte argument
PetscArraymove() should be used instead of PetscMemmove(), it takes a count argument instead of a byte argument
The ./configure options -with-gnu-compilers and -with-vendor-compilers are removed
The ./configure option --with-avx512-kernels defaults to true now so the manually optimized AVX-512 kernels are used by default
The order ./configure tests compilers has changed so there may be a different compiler selected if you do not provide them
Added --with-64-bit-blas-indices that will switch to 64 bit indices when using MKL libraries for BLAS/LAPACK and build OpenBLAS with this support
Changed PETSC_DEPRECATED() to PETSC_DEPRECATED_FUNCTION() and PETSC_DEPRECATED_TYPEDEF() to match naming of PETSC_DEPRECATED_ENUM() and PETSC_DEPRECATED_MACRO
-help now causes the printing of the current value and the newly set value for PetscOptionsInt(), etc
PetscFunctionListPrintTypes() takes an additional final argument after the current value, the set value
PetscCalloc*() now calls the system calloc() routine instead of malloc() plus memzero()
-malloc is now marked as deprecated, use -malloc_debug instead
-malloc_log and -malloc_log_threshold are now -malloc_view and -malloc_view_threshold
PetscMallocDebug() is now PetscMallocSetDebug()
PetscMallocDumpLog() is now PetscMallocView(), see also PetscMallocViewSet()
PetscMallocSetDumpLogThreshold() and PetscMallocSetDumpLog() are now PetscMallocViewSet()
With -malloc_test or -malloc_debug allocated memory is initialized with NaN to detect use of uninitialized numerical arrays
PetscMallocSet() now takes three arguments instead of two
Moved PetscCUBLASGetHandle() to a separate header file petscublas.h
Moved VecCUDA*-routines from petsccuda.h into petscvec.h. Removed petsccuda.h

Configure/Build:

C++ dialect is now auto-detected (C++14 first and then C++11). One can disable this check using --with-cxx-dialect=0, or force it to only check for C++11 using --with-cxx-dialect=C++11
New option --download-hpddm to enable PCHPDDM and KSPHPDDM

IS:

PetscDraw:

PF:

Vec:

VecCUDAGet/RestoreArrayReadWrite() changed to VecCUDAGet/RestoreArray()
VecViennaCLGet/RestoreArrayReadWrite() changed to VecViennaCLGet/RestoreArray()
Added VecGet/RestoreArray/ReadInPlace() to get array of a vector where it is without copying from GPU to CPU.

PetscLayout:

Added PetscLayoutCreateFromSizes()
Added PetscLayoutCreateFromRanges()
Calling PetscLayoutSetUp() twice with different sizes is now forbidden

PetscSection:

VecScatter & PetscSF:

The default VecScatter implementation is changed to PetscSF. In other words, the default VecScatter shares PetscSF's MPI communication code. One can use -vecscatter_type mpi1 to go back to the old implementation.
Added new InsertMode MAX_VALUES and MIN_VALUES support in VecScatterBegin/End and VecGhostUpdateBegin/End.
PetscSFComputeMultiRootOriginalNumbering: add output argument with the number of multiroots for convenience
Added an enum type PetscSFPattern for SF graph patterns. Valid values include PETSCSF_PATTERN_ALLGATHER, PETSCSF_PATTERN_GATHER and PETSCSF_PATTERN_ALLTOALL.
Added PetscSFSetGraphWithPattern() to set SF graphs with predefined patterns.
Added PetscSFComposeInverse() to compose a new SF by putting the inverse of an SF under the another SF.
Added MPI-3.0 neighborhood collectives support. One can use command line option -sf_type neighbor to let SF use MPI-3.0 neighborhood collectives for communication instead of the default MPI_Send/Recv.
PetscSF is now CUDA-aware. The rootdata, leafdata arguments passed to SF routines can be either GPU pointers or CPU pointers. Use a CUDA-aware MPI and option -use_gpu_aware_mpi to enable it.
VecScatter is also CUDA-aware. You can do VecScatter on CUDA vectors without copying them from GPU to CPU. Again, you need a CUDA-aware MPI and option -use_gpu_aware_mpi.
Removed PetscSFCreateFromZero. Instead, users should use PetscSFCreate() to create an SF, and then set its graph with PetscSFSetGraphWithPattern(..,PETSCSF_PATTERN_GATHER).
Renam