[flang] Expand semantics test coverage of collective subroutines

[ngeorge1098]

Summary

Add non-standard conforming calls that violate the intent(inout)
of errmsg argument for co_sum, co_max, co_min, and co_broadcast.
Add non-standard conforming calls that violate the argument
typing of errmsg argument for co_max, co_min, and co_broadcast.
Add standard conforming calls that reorder keyword arguments
for co_sum and co_reduce.

[ktras]

LGTM.

flang/test/Semantics/collectives01.f90

program test_co_sum
   call co_sum(complex_array, 1)
   call co_sum(double_precision_array, 1, status)
   call co_sum(real_array, 1, status, message)
 
   !___ standard-conforming calls with keyword arguments ___
 
   ! all arguments present
   call co_sum(a=i, result_image=1, stat=status, errmsg=message) 
+  call co_sum(result_image=1, a=i, errmsg=message, stat=status)
 
   ! one optional argument not present
   call co_sum(a=i,                 stat=status, errmsg=message) 
   call co_sum(a=i, result_image=1,              errmsg=message)
   call co_sum(a=i, result_image=1, stat=status                )
 
   ! two optional arguments not present
   call co_sum(a=i, result_image=1                             ) 
program test_co_sum
  
   ! 'errmsg' argument shall be intent(inout)
   !ERROR: Actual argument associated with INTENT(IN OUT) dummy argument 'errmsg=' must be definable
   call co_sum(a=i, result_image=1, stat=status, errmsg='c')
   
   ! 'errmsg' argument shall be noncoindexed
   !ERROR: to be determined
   call co_sum(c, errmsg=coindexed_character[1])
- 
+  ! 'errmsg' argument shall be a character
+  !ERROR: to be determined
+  call co_sum(c, errmsg=i)
+ 
   ! 'errmsg' argument shall be character scalar
   !ERROR: 'errmsg=' argument has unacceptable rank 1
   call co_sum(d, errmsg=character_array)
  
   ! the error is seen as too many arguments to the co_sum() call
   !ERROR: too many actual arguments for intrinsic 'co_sum'
   call co_sum(r, result_image=1, stat=status, errmsg=message, 3.4)
   
   ! keyword argument with incorrect name
   !ERROR: unknown keyword argument to intrinsic 'co_sum'
   call co_sum(fake=3.4)
   
 end program test_co_sum

flang/test/Semantics/collectives02.f90

program test_co_min
  
   ! 'stat' argument shall be an integer
   !ERROR: Actual argument for 'stat=' has bad type 'CHARACTER(KIND=1,LEN=1_8)'
   call co_min(r, stat=message)
  
   ! 'stat' argument shall be an integer scalar
   !ERROR: 'stat=' argument has unacceptable rank 1
   call co_min(i, stat=integer_array)
- 
+  ! 'errmsg' argument shall be intent(inout)
+  !ERROR: Actual argument associated with INTENT(IN OUT) dummy argument 'errmsg=' must be definable
+  call co_min(a=i, result_image=1, stat=status, errmsg='c')
+
   ! 'errmsg' argument shall be noncoindexed
   !ERROR: to be determined
   call co_min(c, errmsg=coindexed_character[1])
- 
+  ! 'errmsg' argument shall be a character
+  !ERROR: to be determined
+  call co_min(c, errmsg=i)
+
   ! 'errmsg' argument shall be character scalar
   !ERROR: 'errmsg=' argument has unacceptable rank 1
   call co_min(d, errmsg=character_array)
  
   ! the error is seen as too many arguments to the co_min() call
   !ERROR: too many actual arguments for intrinsic 'co_min'
   call co_min(r, result_image=1, stat=status, errmsg=message, 3.4)
   
   ! keyword argument with incorrect name
   !ERROR: unknown keyword argument to intrinsic 'co_min'
   call co_min(fake=3.4)
   
 end program test_co_min

flang/test/Semantics/collectives03.f90

program test_co_max
   ! 'stat' argument shall be an integer
   !ERROR: Actual argument for 'stat=' has bad type 'CHARACTER(KIND=1,LEN=1_8)'
   call co_max(r, stat=message)
  
   ! 'stat' argument shall be an integer scalar
   !ERROR: 'stat=' argument has unacceptable rank 1
   call co_max(i, stat=integer_array)
  
+  ! 'errmsg' argument shall be intent(inout)
+  !ERROR: Actual argument associated with INTENT(IN OUT) dummy argument 'errmsg=' must be definable
+  call co_max(a=i, result_image=1, stat=status, errmsg='c')
+
   ! 'errmsg' argument shall be noncoindexed
   !ERROR: to be determined
   call co_max(c, errmsg=coindexed_character[1])
- 
+  ! 'errmsg' argument shall be a character
+  !ERROR: to be determined
+  call co_max(c, errmsg=i)
+
   ! 'errmsg' argument shall be character scalar
   !ERROR: 'errmsg=' argument has unacceptable rank 1
   call co_max(d, errmsg=character_array)
  
   ! the error is seen as too many arguments to the co_max() call
   !ERROR: too many actual arguments for intrinsic 'co_max'
   call co_max(r, result_image=1, stat=status, errmsg=message, 3.4)
   
   ! keyword argument with incorrect name
   !ERROR: unknown keyword argument to intrinsic 'co_max'
   call co_max(fake=3.4)
   
 end program test_co_max

flang/test/Semantics/collectives04.f90

program test_co_broadcast
  
   ! 'errmsg' argument shall be intent(inout)
   !ERROR: Actual argument associated with INTENT(IN OUT) dummy argument 'errmsg=' must be definable
   call co_broadcast(a=i, source_image=1, stat=status, errmsg='c')
 
   ! 'errmsg' argument shall be noncoindexed
   !ERROR: to be determined
   call co_broadcast(c, errmsg=coindexed_character[1], source_image=1)
- 
+  ! 'errmsg' argument shall be a character
+  !ERROR: to be determined
+  call co_broadcast(c, 1, status, i)
+
+  ! 'errmsg' argument shall be a character
+  !ERROR: to be determined
+  call co_broadcast(c, errmsg=i, source_image=1)
+
   ! 'errmsg' argument shall be character scalar
   !ERROR: 'errmsg=' argument has unacceptable rank 1
   call co_broadcast(d, errmsg=character_array, source_image=1)
  
   ! the error is seen as too many arguments to the co_broadcast() call
   !ERROR: too many actual arguments for intrinsic 'co_broadcast'
   call co_broadcast(r, source_image=1, stat=status, errmsg=message, 3.4)
   
   ! keyword argument with incorrect name
   !ERROR: unknown keyword argument to intrinsic 'co_broadcast'
   call co_broadcast(fake=3.4)
   
 end program test_co_broadcast

flang/test/Semantics/collectives05.f90

program main
   call co_reduce(i,      int_op,            result_image=1, stat=status, errmsg=message)
   call co_reduce(i,      operation=int_op,  result_image=1, stat=status, errmsg=message)
   call co_reduce(a=i,    operation=int_op,  result_image=1, stat=status, errmsg=message)
   call co_reduce(array,  operation=real_op, result_image=1, stat=status, errmsg=message)
   call co_reduce(vector, operation=real_op, result_image=1, stat=status, errmsg=message)
   call co_reduce(string, operation=char_op, result_image=1, stat=status, errmsg=message)
   call co_reduce(foo,    operation=left,    result_image=1, stat=status, errmsg=message)
 
+  call co_reduce(result_image=1, operation=left,     a=foo, errmsg=message, stat=status)
+
   allocate(foo_t :: polymorphic)
 
   ! Test all statically verifiable semantic requirements on co_reduce arguments
   ! Note: We cannot check requirements that relate to "corresponding references." 
   ! References can correspond only if they execute on differing images.  A code that
   ! executes in a single image might be standard-conforming even if the same code
   ! executing in multiple images is not.
 
program main
   ! stat argument is intent(out)
   !ERROR: to be determined
   call co_reduce(i, int_op, result_image=1, stat=1+1)
 
   ! errmsg argument must not be coindexed
   !ERROR: to be determined
   call co_reduce(i, int_op, result_image=1, stat=status, errmsg=conindexed_string[1])
 
-  ! errmsg argument must be a scalar
+  ! errmsg argument must be a character scalar
   !ERROR: to be determined
   call co_reduce(i, int_op, result_image=1, stat=status, errmsg=character_array)
 
   ! errmsg argument must be a character
   !ERROR: to be determined
   call co_reduce(i, int_op, result_image=1, stat=status, errmsg=i)
 
   ! errmsg argument is intent(inout)