[fortran] Some more function elimination tweaks

Hello world,

the attached patch does the following:

- It removes the restriction on functions returning allocatables
   for elimination (unnecessary since the introduction of allocatable
   temporary variables)

- It allows character function elimination if the character length is
   a constant known at compile time

- It removes introducing temporary variables for the TRANSFER function;
   this is better be handled by the middle-end.

Regression-tested.

OK for trunk?

	Thomas

2011-05-18  Thomas Koenig  <tkoenig@gcc.gnu.org>

         * frontend-passes.c (cfe_register_funcs):  Also register
         character functions if their charlens are known and constant.
         Also register allocatable functions.

2011-05-18  Thomas Koenig  <tkoenig@gcc.gnu.org>

         * gfortran.dg/function_optimize_8.f90:  New test case.
! { dg-do compile }
! { dg-options "-O -fdump-tree-original" }
! Check that duplicate function calls are removed for
! - Functions returning allocatables
! - Character functions with known length
module x
  implicit none
contains
  pure function myfunc(x) result(y)
    integer, intent(in) :: x
    integer, dimension(:), allocatable :: y
    allocate (y(3))
    y(1) = x
    y(2) = 2*x
    y(3) = 3*x
  end function myfunc

  pure function mychar(x) result(r)
    integer, intent(in) :: x
    character(len=2) :: r
    r = achar(x + iachar('0')) // achar(x + iachar('1'))
  end function mychar
end module x

program main
  use x
  implicit none
  integer :: n
  character(len=20) :: line
  n = 3
  write (unit=line,fmt='(3I2)') myfunc(n) + myfunc(n)
  if (line /= ' 61218') call abort
  write (unit=line,fmt='(A)') mychar(2) // mychar(2)
  if (line /= '2323') call abort
end program main
! { dg-final { scan-tree-dump-times "myfunc" 2 "original" } }
! { dg-final { scan-tree-dump-times "mychar" 2 "original" } }
! { dg-final { cleanup-tree-dump "original" } }
! { dg-final { cleanup-modules "x" } }

On Wed, May 18, 2011 at 10:58:18PM +0200, Thomas Koenig wrote:
> 
> - It removes the restriction on functions returning allocatables
>   for elimination (unnecessary since the introduction of allocatable
>   temporary variables)
> 
> - It allows character function elimination if the character length is
>   a constant known at compile time
> 
> - It removes introducing temporary variables for the TRANSFER function;
>   this is better be handled by the middle-end.
> 
> Regression-tested.
> 
> OK for trunk?
> 
> 	Thomas
> 
> 2011-05-18  Thomas Koenig  <tkoenig@gcc.gnu.org>
> 
>         * frontend-passes.c (cfe_register_funcs):  Also register
>         character functions if their charlens are known and constant.
>         Also register allocatable functions.
> 
> 2011-05-18  Thomas Koenig  <tkoenig@gcc.gnu.org>
> 
>         * gfortran.dg/function_optimize_8.f90:  New test case.

OK.

Hi Steve,

>>          * frontend-passes.c (cfe_register_funcs):  Also register
>>          character functions if their charlens are known and constant.
>>          Also register allocatable functions.
>>
>> 2011-05-18  Thomas Koenig<tkoenig@gcc.gnu.org>
>>
>>          * gfortran.dg/function_optimize_8.f90:  New test case.
>
> OK.

Waiting for Emacs...
Sende          fortran/ChangeLog
Sende          fortran/frontend-passes.c
Sende          testsuite/ChangeLog
Hinzufügen     testsuite/gfortran.dg/function_optimize_8.f90
Übertrage Daten ....
Revision 174027 übertragen

Thanks a lot for the review!

	Thomas