One-liners from petsc/petsc!5344 and petsc/petsc!5557

Slightly reworked regular expression

git ls-files -z -- '*.c' '*.cxx' '*.cu' '*.h' '*.hpp' '*.cpp' | while IFS= read -r -d '' file; do
cat

One-liners from petsc/petsc!5344 and petsc/petsc!5557

Slightly reworked regular expression

git ls-files -z -- '*.c' '*.cxx' '*.cu' '*.h' '*.hpp' '*.cpp' | while IFS= read -r -d '' file; do
cat $file | tr '\n' '\r' | sed -E 's/\r([ ]*)(for|if|while|else) ([^\r]*)\{\r[ ]*Petsc([a-zA-Z]*)\(([^\r]*)\);\r[ ]*\}\r/\r\1\2 \3Petsc\4(\5);\r/g' | tr '\r' '\n' > ${file}.joe; mv ${file}.joe ${file}
done

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Mat: Fix and improve the performance of dense matrix multiplication

Mat: Add MATDENSEFROMVECTYPE constructor type

Now in a tests set you can do

```
testset:
args: -mat_type densefromvectype

Mat: Fix and improve the performance of dense matrix multiplication

Mat: Add MATDENSEFROMVECTYPE constructor type

Now in a tests set you can do

```
testset:
args: -mat_type densefromvectype
test: test_cuda
requires: cuda
args: -vec_type veccuda
test: test_hip
requires: hip
args: -vec_type vechip
```

(This assumes that you call `MatSetVecType()` before you call
`MatSetFromOptions()`)

Mat_MPIDense: Cache offsets of MatDenseGetSubMatrix() to avoid communication in more cases

Mat: Add missing implementations for internal "MatMultColumnRange()" interface

Mat_MPIDense: Fix the zeroing of buffers in multiplication routines

Mat_MPIDense: Add optimization of MatMatMult routines when all columns are owned by rank 0

The communication for intermediate buffers can be handled with allreduce / bcast operations,
but we use the PetscSF matvec context instead of MPI routines directly so that we will
use gpu-aware MPI if possible.

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Partially revert !8099 for non-blocking collectives

Remove unneeded PetscMPIIntCast() for routines using PetscCount

Fix #1661