WIP: Multiprecision Build

[oseikuffuor1]

This PR will introduce multiprecision capabilities into master.

hypre currently supports single, double and longdouble precision in independent builds. This PR will enable an interoperable build of hypre in the different precisions. This will enable mixed-precision code development in hypre. Key components include:

1. An updated build system that allows building hypre with multiprecision capabilties turned on
2. Scripts to check and update the multiprecision build
3. New header files that identify multiprecision functions
4. Mixed-precision Krylov solver capabilities
5. Capability to use a different operator for the preconditioner than the matrix operator (for Krylov solvers)

To Do:

1. Cleanup warnings/ errors on macOS, etc.
2. Fixes for memory alignment bug
3. Updated mixed-precision AMG utilizing fixes in 1.
4. Review from the hypre team

[victorapm]

Do we need both hypre_Vector_mp and hypre_Vector?

[oseikuffuor1]

Yes actually. This was necessary to allow mixed-precision vector operations. However, when To Do item 2 is completed, this may take on a different form.

[victorapm]

Ok! It would be nice to remove the duplications if we could

[victorapm]

I'm seeing an error when building on a Mac ./configure --enable-mixed-precision

mpicc -O2  -DHAVE_CONFIG_H -I.. -I. -I./.. -I./../utilities           -c seq_mv_mp.c
seq_mv_mp.c:115:10: error: call to undeclared function 'hypre_error_handler_dbl'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
         hypre_error_w_msg_mp(HYPRE_ERROR_GENERIC, "Error: Undefined precision type for Vector Copy!\n");
         ^
./../utilities/_hypre_utilities.h:683:42: note: expanded from macro 'hypre_error_w_msg_mp'
#define hypre_error_w_msg_mp(IERR, msg)  hypre_error_handler_dbl(__FILE__, __LINE__, IERR, msg)
                                         ^
seq_mv_mp.c:115:10: note: did you mean 'hypre_error_handler'?
./../utilities/_hypre_utilities.h:683:42: note: expanded from macro 'hypre_error_w_msg_mp'
#define hypre_error_w_msg_mp(IERR, msg)  hypre_error_handler_dbl(__FILE__, __LINE__, IERR, msg)
                                         ^
./../utilities/_hypre_utilities.h:678:6: note: 'hypre_error_handler' declared here
void hypre_error_handler(const char *filename, HYPRE_Int line, HYPRE_Int ierr, const char *msg);
     ^
./../utilities/utilities_mup_func.h:52:57: note: expanded from macro 'hypre_error_handler'
#define hypre_error_handler HYPRE_MULTIPRECISION_FUNC ( hypre_error_handler )
                                                        ^
seq_mv_mp.c:173:10: error: call to undeclared function 'hypre_error_handler_dbl'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
         hypre_error_w_msg_mp(HYPRE_ERROR_GENERIC, "Error: Undefined precision type for Vector Axpy!\n");
         ^
./../utilities/_hypre_utilities.h:683:42: note: expanded from macro 'hypre_error_w_msg_mp'
#define hypre_error_w_msg_mp(IERR, msg)  hypre_error_handler_dbl(__FILE__, __LINE__, IERR, msg)
                                         ^

[oseikuffuor1]

I'm seeing an error when building on a Mac ./configure --enable-mixed-precision

mpicc -O2  -DHAVE_CONFIG_H -I.. -I. -I./.. -I./../utilities           -c seq_mv_mp.c
seq_mv_mp.c:115:10: error: call to undeclared function 'hypre_error_handler_dbl'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
         hypre_error_w_msg_mp(HYPRE_ERROR_GENERIC, "Error: Undefined precision type for Vector Copy!\n");
         ^
./../utilities/_hypre_utilities.h:683:42: note: expanded from macro 'hypre_error_w_msg_mp'
#define hypre_error_w_msg_mp(IERR, msg)  hypre_error_handler_dbl(__FILE__, __LINE__, IERR, msg)
                                         ^
seq_mv_mp.c:115:10: note: did you mean 'hypre_error_handler'?
./../utilities/_hypre_utilities.h:683:42: note: expanded from macro 'hypre_error_w_msg_mp'
#define hypre_error_w_msg_mp(IERR, msg)  hypre_error_handler_dbl(__FILE__, __LINE__, IERR, msg)
                                         ^
./../utilities/_hypre_utilities.h:678:6: note: 'hypre_error_handler' declared here
void hypre_error_handler(const char *filename, HYPRE_Int line, HYPRE_Int ierr, const char *msg);
     ^
./../utilities/utilities_mup_func.h:52:57: note: expanded from macro 'hypre_error_handler'
#define hypre_error_handler HYPRE_MULTIPRECISION_FUNC ( hypre_error_handler )
                                                        ^
seq_mv_mp.c:173:10: error: call to undeclared function 'hypre_error_handler_dbl'; ISO C99 and later do not support implicit function declarations [-Wimplicit-function-declaration]
         hypre_error_w_msg_mp(HYPRE_ERROR_GENERIC, "Error: Undefined precision type for Vector Axpy!\n");
         ^
./../utilities/_hypre_utilities.h:683:42: note: expanded from macro 'hypre_error_w_msg_mp'
#define hypre_error_w_msg_mp(IERR, msg)  hypre_error_handler_dbl(__FILE__, __LINE__, IERR, msg)
                                         ^

Thanks Victor. This appears as a warning for me (and I believe Rob as well) on my Mac. I intend to clean this and other warnings up. I should have listed that in the to-dos