Hello,
My colleague and I want to implement a compile-time check (warning)
for clang compiler that specified buffer type matches passed
MPI_Datatype.
For example:
MPI_Send(long_buf, 1, MPI_INT, 1, 1, MPI_COMM_WORLD); //
expected-warning {{actual buffer element type 'long' doesn't match
specified MPI_Datatype}}
We've hacked a prototype patch for clang, but first we wanted to
discuss this idea with OpenMPI developers.
Here's what is required on the OpenMPI part: all MPI functions that
accept a buffer and MPI_Datatype should be annotated with
mpi_typed_arg(buffer-arg-index, type-arg-index) attribute. For
example:
int MPI_Send(void *buf, ...etc...) __attribute__(( mpi_typed_arg(1,3) ));
Predefined datatypes should be annotated with corresponding C types:
mpi_datatype(var-decl-with-corresponding-type):
extern int ompi_mpi_int_dummy;
extern struct ompi_predefined_datatype_t ompi_mpi_int
__attribute__(( mpi_datatype(ompi_mpi_int_dummy) ));
Users can annotate their types too:
int my_int_dummy;
MPI_Datatype my_int_type __attribute__(( mpi_datatype(my_int_dummy) ));
This design is not final, I'd really like to have mpi_datatype(type)
(e.g., mpi_datatype(long long)) but clang doesn't currently have
support for parsing that. (But I think that clang developers won't
accept the patch unless we implement that). So type annotations will
probably look like:
extern struct ompi_predefined_datatype_t ompi_mpi_int
__attribute__(( mpi_datatype(int) ));
The attributes can be hidden with macros from compilers that don't
support them, so compatibility should not be a problem.
See attached test and clang output to see what will it look like.
Any comments are welcome. Please also tell me if you have any ideas
for additional compile-time checks.
I would like to hear if there is any issue with this idea or
implementation design that could prevent the corresponding patch for
mpi.h to be accepted.
Dmitri Gribenko
--
main(i,j){for(i=2;;i++){for(j=2;j<i;j++){if(!(i%j)){j=0;break;}}if
(j){printf("%d\n",i);}}} /*Dmitri Gribenko <griboz...@gmail.com>*/
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:10:21: error:
attribute requires exactly 2 arguments
__attribute__(( mpi_typed_arg )); // expected-error {{attribute requires
exactly 2 arguments}}
^
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:13:21: error:
'mpi_typed_arg' attribute parameter 1 is out of bounds
__attribute__(( mpi_typed_arg(0,7) )); // expected-error {{attribute
parameter 1 is out of bounds}}
^ ~
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:16:21: error:
'mpi_typed_arg' attribute parameter 1 is out of bounds
__attribute__(( mpi_typed_arg(5,7) )); // expected-error {{attribute
parameter 1 is out of bounds}}
^ ~
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:19:21: error:
'mpi_typed_arg' attribute parameter 2 is out of bounds
__attribute__(( mpi_typed_arg(3,0) )); // expected-error {{attribute
parameter 2 is out of bounds}}
^ ~
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:22:21: error:
'mpi_typed_arg' attribute parameter 2 is out of bounds
__attribute__(( mpi_typed_arg(3,5) )); // expected-error {{attribute
parameter 2 is out of bounds}}
^ ~
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:27:21: error:
'mpi_typed_arg' attribute requires parameter 1 to be an integer constant
__attribute__(( mpi_typed_arg((x+1),7) )); // expected-error {{attribute
requires parameter 1 to be an integer constant}}
^ ~~~~~
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:30:21: error:
'mpi_typed_arg' attribute requires parameter 2 to be an integer constant
__attribute__(( mpi_typed_arg(3,x) )); // expected-error {{attribute
requires parameter 2 to be an integer constant}}
^ ~
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:32:34: error:
'mpi_typed_arg' attribute only applies to functions and methods
int MPI_Wrong8() __attribute__(( mpi_typed_arg(1,3) )); // expected-error
{{attribute only applies to functions and methods}}
^
MPITypedArgAttr1 3
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:45:74: error:
attribute takes one argument
extern struct ompi_predefined_datatype_t ompi_mpi_wrong1 __attribute__((
mpi_datatype )); // expected-error {{attribute takes one argument}}
^
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:46:74: error:
attribute takes one argument
extern struct ompi_predefined_datatype_t ompi_mpi_wrong2 __attribute__((
mpi_datatype(1,2) )); // expected-error {{attribute takes one argument}}
^
handleMPIDatatypeAttr err1
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:61:12: warning:
actual buffer element type 'long' doesn't match specified MPI_Datatype [-Wmpi]
MPI_Send(long_buf, 1, MPI_INT, 1, 1, MPI_COMM_WORLD); // expected-warning
{{actual buffer element type 'long' doesn't match specified MPI_Datatype}}
^~~~~~~~ ~~~~~~~
../../../llvm/tools/clang/test/Sema/warn-mpi-type-mismatch.c:71:12: warning:
actual buffer element type 'long' doesn't match specified MPI_Datatype [-Wmpi]
MPI_Send(long_buf, 1, my_int_type, 1, 1, MPI_COMM_WORLD); // expected-warning
{{actual buffer element type 'long' doesn't match specified MPI_Datatype}}
^~~~~~~~ ~~~~~~~~~~~
2 warnings and 10 errors generated.
// RUN: %clang_cc1 -fsyntax-only -verify %s
//===--- mpi.h mock -------------------------------------------------------===//
typedef struct ompi_communicator_t *MPI_Comm;
typedef struct ompi_datatype_t *MPI_Datatype;
int MPI_Wrong1(void *buf, int count, MPI_Datatype datatype, int dest,
int tag, MPI_Comm comm)
__attribute__(( mpi_typed_arg )); // expected-error {{attribute requires exactly 2 arguments}}
int MPI_Wrong2(void *buf, int count, MPI_Datatype datatype)
__attribute__(( mpi_typed_arg(0,7) )); // expected-error {{attribute parameter 1 is out of bounds}}
int MPI_Wrong3(void *buf, int count, MPI_Datatype datatype)
__attribute__(( mpi_typed_arg(5,7) )); // expected-error {{attribute parameter 1 is out of bounds}}
int MPI_Wrong4(void *buf, int count, MPI_Datatype datatype)
__attribute__(( mpi_typed_arg(3,0) )); // expected-error {{attribute parameter 2 is out of bounds}}
int MPI_Wrong5(void *buf, int count, MPI_Datatype datatype)
__attribute__(( mpi_typed_arg(3,5) )); // expected-error {{attribute parameter 2 is out of bounds}}
extern int x;
int MPI_Wrong6(void *buf, int count, MPI_Datatype datatype)
__attribute__(( mpi_typed_arg((x+1),7) )); // expected-error {{attribute requires parameter 1 to be an integer constant}}
int MPI_Wrong7(void *buf, int count, MPI_Datatype datatype)
__attribute__(( mpi_typed_arg(3,x) )); // expected-error {{attribute requires parameter 2 to be an integer constant}}
int MPI_Wrong8() __attribute__(( mpi_typed_arg(1,3) )); // expected-error {{attribute only applies to functions and methods}}
int MPI_Send(void *buf, int count, MPI_Datatype datatype, int dest,
int tag, MPI_Comm comm)
__attribute__(( mpi_typed_arg(1,3) ));
#define OMPI_PREDEFINED_GLOBAL(type, global) ((type) &(global))
#define MPI_COMM_WORLD OMPI_PREDEFINED_GLOBAL(MPI_Comm, ompi_mpi_comm_world)
extern struct ompi_predefined_communicator_t ompi_mpi_comm_world;
#define MPI_INT OMPI_PREDEFINED_GLOBAL(MPI_Datatype, ompi_mpi_int)
#define MPI_LONG_LONG_INT OMPI_PREDEFINED_GLOBAL(MPI_Datatype, ompi_mpi_long_long_int)
extern struct ompi_predefined_datatype_t ompi_mpi_wrong1 __attribute__(( mpi_datatype )); // expected-error {{attribute takes one argument}}
extern struct ompi_predefined_datatype_t ompi_mpi_wrong2 __attribute__(( mpi_datatype(1,2) )); // expected-error {{attribute takes one argument}}
extern struct ompi_predefined_datatype_t ompi_mpi_wrong1 __attribute__(( mpi_datatype(ompi_mpi_wrong1_dummy) ));
extern int ompi_mpi_int_dummy;
extern struct ompi_predefined_datatype_t ompi_mpi_int __attribute__(( mpi_datatype(ompi_mpi_int_dummy) ));
extern long long int ompi_mpi_long_long_int_dummy;
extern struct ompi_predefined_datatype_t ompi_mpi_long_long_int __attribute__(( mpi_datatype(ompi_mpi_long_long_int_dummy) ));
//===--- Tests ------------------------------------------------------------===//
void test1(int *int_buf, long *long_buf)
{
MPI_Send(int_buf, 1, MPI_INT, 1, 1, MPI_COMM_WORLD); // no-warning
MPI_Send(long_buf, 1, MPI_INT, 1, 1, MPI_COMM_WORLD); // expected-warning {{actual buffer element type 'long' doesn't match specified MPI_Datatype}}
}
int my_int_dummy;
MPI_Datatype my_int_type __attribute__(( mpi_datatype(my_int_dummy) ));
MPI_Datatype my_unknown_type;
void test2(long *long_buf)
{
MPI_Send(long_buf, 1, my_int_type, 1, 1, MPI_COMM_WORLD); // expected-warning {{actual buffer element type 'long' doesn't match specified MPI_Datatype}}
MPI_Send(long_buf, 1, my_unknown_type, 1, 1, MPI_COMM_WORLD); // no-warning
}
void test3(int *buf, MPI_Datatype type)
{
MPI_Send(buf, 1, type, 1, 1, MPI_COMM_WORLD); // no-warning
}
